Handbook of Evidence-Based Critical Care

Paul Ellis MarikHandbook of Evidence-Based Critical CareSecond10.1007/978-1-4419-5923-2_1© Springer Science+Business Media, LLC 2010

1. Evidence-Based Critical Care

Paul Ellis Marik¹  

(1)

Division of Pulmonary and Critical Care Medicine, Eastern Virginia Medical School, Norfolk, VA, USA

Paul Ellis Marik

Email: [email protected]

Abstract

Before medicine developed its scientific basis of pathophysiology, clinical practice was learned empirically from the events of daily experience in diagnosing and treating the maladies patients presented. Students learned as apprentices to clinicians, observing the phenomena of disease, the skill of diagnosis and treatment, and the outcomes of different remedies. Sir William Osler’s classic textbook of medicine was based almost entirely on his personal experience correlated with the general experience of others.¹ With advances in our understanding of human physiology and the pathophysiological basis of disease, these remedies fell by the wayside and treatment became based on modalities of treatment that were shown to interrupt or otherwise modify the disease process. Until recently, it was considered sufficient to understand the disease process in order to prescribe a drug or other form of treatment. However, when these treatment modalities were subjected to randomized, controlled clinical trials (RCTs) examining clinical outcomes and not physiological processes, the outcome was not always favorable. The RCT has become the reference in medicine by which to judge the effect of an intervention on patient outcome, because it provides the greatest justification for conclusion of causality, is subject to the least bias, and provides the most valid data on which to base all measures of the benefits and risk of particular therapies.² Numerous ineffective and harmful therapies have been abandoned as a consequence of RCTs, while others have become integral to the care of patients and have become regarded as the standard of care.

There are in fact two things, science and opinion; the former begets knowledge, the latter ignorance.

–Hippocrates (c460–c377 BCE), Greek physician

Before medicine developed its scientific basis of pathophysiology, clinical practice was learned empirically from the events of daily experience in diagnosing and treating the maladies patients presented. Students learned as apprentices to clinicians, observing the phenomena of disease, the skill of diagnosis and treatment, and the outcomes of different remedies. Sir William Osler’s classic textbook of medicine was based almost entirely on his personal experience correlated with the general experience of others.1 With advances in our understanding of human physiology and the pathophysiological basis of disease, these remedies fell by the wayside and treatment became based on modalities of treatment that were shown to interrupt or otherwise modify the disease process. Until recently, it was considered sufficient to understand the disease process in order to prescribe a drug or other form of treatment. However, when these treatment modalities were subjected to randomized, controlled clinical trials (RCTs) examining clinical outcomes and not physiological processes, the outcome was not always favorable. The RCT has become the reference in medicine by which to judge the effect of an intervention on patient outcome, because it provides the greatest justification for conclusion of causality, is subject to the least bias, and provides the most valid data on which to base all measures of the benefits and risk of particular therapies.2 Numerous ineffective and harmful therapies have been abandoned as a consequence of RCTs, while others have become integral to the care of patients and have become regarded as the standard of care.

Many RCTs are, however, inconclusive or provide conflicting results. In this situation, systematic reviews that are based on meta-analysis of published (and unpublished) RCTs are clearly the best strategy for appraising the available evidence. While meta-analyses have many limitations, they provide the best means of determining the significance of the treatment effect from inconclusive or conflicting RCTs. Furthermore, as a result of publication bias, positive studies are more likely to be published and usually in more prestigious journals than are negative studies. A clinician may base his/her therapeutic decisions on these selected RCTs which may then lead to inappropriate patient care. It is therefore important that common medical interventions be systematically reviewed and the strength of the evidence (either positive or negative) be evaluated. Although over 250,000 RCTs have been performed, for many clinical problems, there are no RCTs to which we can refer to answer our questions. In these circumstances, we need to base our clinical decisions on the best evidence available from experimental studies, cohort studies, case series, and systematic reviews.

Every decision that the clinician makes must be based on sound scientific evidence (a collection of anecdotes is not scientific evidence). Science is the continuing effort to discover and increase human knowledge and understanding through disciplined research. Using controlled methods, scientists collect observable evidence, record measurable data relating to the observations, and analyze this information to construct explanations of how things work.3 Intuition, anecdotes, common sense, personal biases, and clinical experience are not considered science and cannot be used to justify clinical decision making or therapeutic policies.

While Evidence-Based Medicine (EBM) is frequently criticized as cookbook medicine, this is most certainly not the case. Rather, the best scientific evidence should be applied to the unique characteristics of each patient.2 Each patient is unique, and the art of medicine is the ability to integrate and apply the best scientific knowledge to each patient. Checklists may be fine if you are flying an airplane; however, patients are not airplanes and doctors are not pilots.4,5 While the response to pushing a button or pulling a lever on a Boeing 737-400 is entirely predictable (with the same reproducible result), the response of any given patient to a volume challenge or an injection of a β-blocker is dependent on a myriad of physiological/pathophysiological factors, with the response not being entirely predictable. Furthermore, intensivists evaluate and provide care to the entire patient and are not single-organ physicians that merely adjust the rudder or lower the landing gear and hope for the best!4 Clinical practice guidelines (CPGs), which are evidence-based and up-to-date, are useful in providing the clinician with direction but should never be followed blindly. Rigid protocols and policies, have little place in clinical medicine.

As critical care medicine has evolved into a discreet specialty that crosses anatomical and other artificial boundaries and deals with an enormous array of human conditions, it has become evident that to achieve the best outcomes for our very complex patients, all our clinical decisions should be based on the best available evidence. The complexity of the critically ill patient together with the vast armamentarium of therapeutic options available makes it essential that we critically evaluate established and emerging clinical practices. Bone throwing, bloodletting, witchcraft, and other forms of hocus-pocus have no role in modern critical care. However, it is important to realize that critical care medicine can be practiced only by close observation of the patient (at the bedside), by contemplation, and by the integration of a large data base of evidence-based medicine together with a good deal of humility.

The Handbook of Evidence-Based Critical Care is not a reference text but presents a practical evidence-based approach to the management of critically ill ICU patients. Due to the vast number of therapeutic interventions that ICU physicians make daily, the topics are presented as narrative summaries of the best available evidence rather than as systematic reviews of each and every intervention. While all attempts have been made to be current, due to the exponential growth of medical knowledge, some of the information presented may already be outdated when this book comes to print. The reader therefore should keep up-to-date with the current medical literature. In keeping with the goal of providing an evidence-based approach to critical care, references are provided to support the evidence presented.

Alert

The guidelines presented in the book are not meant to replace clinical judgment but rather to provide a framework to patient management. Individual clinical situations can be highly complex and the judgment and wisdom of an experienced and knowledgeable intensivist with all available information about a specific patient is essential for optimal clinical management.

References

1.

Osler W. Preface. The Principles and Practice of Medicine. 8th ed. New York: D. Appleton & Co.; 1918.

2.

Sackett DL, Richardson WS, Rosenberg W, Haynes RB. Evidence-Based Medicine. How to Practice and Teach EBM. New York: Churchill Livingstone; 1997.

3.

Science. http://en.wikipedia.org/wiki/Science. Wikipedia. Accessed December 3, 2009.

4.

Rissmiller R. Patients are not airplanes and doctors are not pilots [Letter]. Crit Care Med. 2006;34:2869.PubMedCrossRef

5.

Laurance J. Peter Pronovost: champion of checklists in critical care. Lancet. 2009;374:443.PubMedCrossRef

Paul Ellis MarikHandbook of Evidence-Based Critical CareSecond10.1007/978-1-4419-5923-2_2© Springer Science+Business Media, LLC 2010

2. Classic Critical Care Papers

Paul Ellis Marik¹  

(1)

Division of Pulmonary and Critical Care Medicine, Eastern Virginia Medical School, Norfolk, VA, USA

Paul Ellis Marik

Email: [email protected]

Abstract

A limited number of publications have had a dramatic impact on the practice of critical care medicine. These publications are regarded as compulsory reading for residents, fellows, and other practitioners of critical care medicine. Surprisingly, although not unexpectedly, those publications with the potential to have the most dramatic positive impact on patient care have been slow to be adopted, while publications of questionable scientific rigor are frequently adopted with an unexplained religious fervor. This chapter reviews those papers which have dramatically altered the practice of critical care medicine (for good or bad) as well as those classic papers that have shaped the history of critical care medicine.

A limited number of publications have had a dramatic impact on the practice of critical care medicine. These publications are regarded as compulsory reading for residents, fellows, and other practitioners of critical care medicine. Surprisingly, although not unexpectedly, those publications with the potential to have the most dramatic positive impact on patient care have been slow to be adopted, while publications of questionable scientific rigor are frequently adopted with an unexplained religious fervor. This chapter reviews those papers which have dramatically altered the practice of critical care medicine (for good or bad) as well as those classic papers that have shaped the history of critical care medicine.

Perhaps the most important publication in the history of critical care medicine is that of the ARDSNet low vs. standard tidal volume study.1 This study demonstrated a significant reduction in 28-day mortality in patients randomized to the low tidal volume group (6 ml/kg PBW) as compared to the traditional tidal volume (12 ml/kg PBW) group. The results of this study are supported by extensive experimental and clinical studies. Furthermore, high tidal volumes are associated with progressive lung injury in patients who initially do not have acute lung injury. A tidal volume of 6–8 ml/kg is therefore considered the standard of care for all ICU patients. A follow-up study by the ARDSNet group suggested that a fluid management strategy that aims to keep patients dry improves patient outcome (significant increase in ventilator-free days).

Kress and colleagues2 demonstrated that in patients who are receiving mechanical ventilation, daily interruption of sedative drug infusions decreases the duration of mechanical ventilation and the length of stay in the intensive care. Ely and colleagues3,4 have demonstrated that a non-physician-directed protocol of spontaneous breathing trials expedites weaning and shortens the duration of mechanical ventilation. Recently, Girard and colleagues5 demonstrated that a wake up and breathe protocol that pairs daily spontaneous awakening trials (i.e., interruption of sedatives) with daily spontaneous breathing trials results in better outcomes for mechanically ventilated patients than do the standard approaches. This approach should be considered the standard of care in all ICU patients.

Blood transfusions and the choice of resuscitation fluid have until recently been a controversial issue. In a landmark study, Hebert and colleagues6 compared a conservative (transfusion for Hb <7 g/dl) vs. liberal (transfusion for Hb <10 g/dl) blood transfusion protocol. In this study the complication rate and 28-day mortality tended to be lower in the conservative group. These results of this study are supported by a meta-analysis of cohort studies, which clearly establishes the benefits of a restrictive blood transfusion strategy.7 The SAFE study demonstrated the safety of albumin in critically ill patients,8 while the VISEP study demonstrated an increased risk of renal failure and death in critically ill patients resuscitated with a hydroxyethyl starch solution.9

Beginning in the 1960s, Dr. Max Harry Weil10,11 (the father of critical care medicine) demonstrated the relationship between lactate and the reversibility of shock. Furthermore, in what is now a landmark study, Dr. Weil and colleagues12 demonstrated a marked difference in arterial and mixed venous acid–base status in patients undergoing CPR. These studies ushered in our current approach to the monitoring of tissue oxygenation in the critically ill patients.

In 1982, Shoemaker and colleagues13 published a study suggesting that achieving supranormal levels of oxygen delivery improved the outcome of critically ill patients. This approach became very fashionable in the late 1980s and the early 1990s and became part of the ICU culture encouraging the (excessive) use of the pulmonary artery catheter (PAC). Subsequent, RCTs were unable to demonstrate the benefit of this approach with the suggestion that driving up oxygen delivery to the magical end points proposed by Shoemaker and colleagues may be harmful (this became a popular theme!).14, 15

The classic study by Connors et al.16 in 1996 raised the possibility that the PAC may be harmful in critically ill patients. Subsequent studies have been unable to demonstrate any benefit associated with the use of the PAC.17 While the use of the PCWP (pulmonary capillary wedge pressure) as measured using the PAC has fallen into disfavor, the central venous pressure (CVP) continues to be used universally to guide fluid management despite convincing evidence that this measurement is as useful as flipping a coin.18

The diagnosis and treatment of ventilator-associated pneumonia (VAP) is an important issue in the ICU. Fagon and colleagues19 compared a diagnostic approach based on lower respiratory tract sampling and quantitative culture with that of the standard approach. Compared with the non-invasive strategy, the invasive strategy was associated with fewer deaths at 14 days, earlier resolution of organ dysfunction or less antibiotic use in patients suspected of having VAP. Chastre and colleagues20 compared 8 vs. 15 days of antibiotic therapy in patients with VAP. There was no difference in outcome between the two groups (with the possible exception of those with pseudomonas pneumonia).

Until recently, the optimal dosing of intermittent hemodialysis (IHD) and continuous renal replacement therapy in the ICU was unclear with data suggesting that more aggressive renal replacement therapy (RRT) was associated with improved renal recovery. The VA/NIH Acute Renal Failure Trial Network randomized 1,124 patients with ARF to receive intensive or less intensive RRT.21 Hemodynamically stable patients underwent IHD (6 vs. 3 times per week) and hemodynamically unstable patients underwent CVVHD (35 vs. 20 ml/kg/h). There was no difference in clinical outcomes between the two groups of patients.

November the 8th was a dark day in the history of critical care. On that day two studies were published in the New England Journal of Medicine which changed (overnight) the way critical care was practiced around the world.22,23 Rivers and colleagues23 randomized 288 patients with severe sepsis and septic shock to early goal-directed therapy (EGDT) or standard care. EGDT was reported to be associated with a 16% absolute reduction of hospital death (35% relative reduction in death). Based on this single study, EGDT became adopted as the standard of care around the world and has become the cornerstone of the recommendations of the Surviving Sepsis Campaign.24,25 It is however important to recognize that this was an unblinded, small, single-center study with investigators who were highly invested in the outcome of the study. By any stretch of the imagination the results of this study were too good to be true. Recent evidence questions the validity of the findings of the study (see Wall Street Journal, lead report, August 14th 2008).26 While the concept of EGDT intuitively makes sense, the role of the central venous oxygen saturation and a CVP >8 cm H2O as the end points of resuscitation in septic patients is questionable (and not validated) as is the liberal use of blood and other interventions called for by the EGDT protocol (see Chapters 8,10, and 51). Stay tuned to this interesting saga; a sequel is in the works! [Protocolized Care for Early Septic Shock (ProCESS); NCT00510835]

On the same day that the EGDT study was published, the Leuven Intensive Insulin Therapy Trial #1 appeared in the NEJM.22 This study compared the outcome of patients randomized to an insulin infusion protocol that achieved tight glycemic control (blood glucose 70–110 mg/dl) as compared to standard glycemic control (blood glucose 180–200 mg/dl). This study demonstrated a significant reduction in morbidity and mortality in the patients randomized to the tight glycemic group. Similar to EGDT, based on this single-center, unblinded study performed by highly invested investigators, tight glycemic control became adopted overnight as the standard of care throughout the world.27 Subsequent studies have failed to reproduce the findings of van den Berghe et al. and tight glycemic control should now be abandoned.

The role of corticosteroids in patients with sepsis and ARDS is controversial. Landmark studies by Annane et al. and Meduri et al. suggested that corticosteroids reduced 28-day mortality in ICU patients with septic shock and ARDS (late), respectively.28,29 The results of more recent studies have further fueled this controversy.30–32

References

1.

Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. N Engl J Med. 2000;342:1301–1308.

2.

Kress JP, Pohlman AS, O’Connor MF, et al. Daily interruption of sedative infusions in critically ill patients undergoing mechanical ventilation. N Engl J Med. 2000;342:1471–1477.PubMedCrossRef

3.

Ely EW, Baker AM, Dunagan DP, et al. Effect on the duration of mechanical ventilation of identifying patients capable of breathing spontaneously. N Engl J Med. 1996;335:1864–1869.PubMedCrossRef

4.

Ely EW, Bennett PA, Bowton DL, et al. Large scale implementation of a respiratory therapist-driven protocol for ventilator weaning. Am J Respir Crit Care Med. 1999;159:439–446.PubMed

5.

Girard TD, Kress JP, Fuchs BD, et al. Efficacy and safety of a paired sedation and ventilator weaning protocol for mechanically ventilated patients in intensive care (Awakening and Breathing Controlled trial): a randomised controlled trial. Lancet. 2008;371:126–134.PubMedCrossRef

6.

Hebert PC, Wells G, Blajchman MA, et al. A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. Transfusion Requirements in Critical Care Investigators, Canadian Critical Care Trials Group. N Engl J Med. 1999;340:409–417.PubMedCrossRef

7.

Marik PE, Corwin HL. Efficacy of RBC transfusion in the critically ill: a systematic review of the literature. Crit Care Med. 2008;36:2667–2674.PubMedCrossRef

8.

Finfer S, Bellomo R, Boyce N, et al. A comparison of albumin and saline for fluid resuscitation in the intensive care unit. N Engl J Med. 2004;350:2247–2256.PubMedCrossRef

9.

Brunkhorst FM, Engel C, Bloos F, et al. Intensive insulin therapy and pentastarch resuscitation in severe sepsis. N Engl J Med. 2008;358:125–139.PubMedCrossRef

10.

Broder G, Weil MH. Excess lactate: an index of reversibility of shock in human patients. Science. 1964;143:1457–1459.PubMedCrossRef

11.

Weil MH, Afifi AA. Experimental and clinical studies on lactate and pyruvate as indicators of the severity of acute circulatory failure (shock). Circulation. 1970;41:989–1001.PubMedCrossRef

12.

Weil MH, Rackow E, Trevino R. Difference in acid–base state between venous and arterial blood during cardiopulmonary resuscitation. N Engl J Med. 1986;315:153–156.PubMedCrossRef

13.

Shoemaker WC, Appel PL, Waxman K, et al. Clinical trial of survivors cardiorespiratory patterns as therapeutic goals in critically ill postoperative patients. Crit Care Med. 1982;10:398–403.PubMedCrossRef

14.

Gattinoni L, Brazzi L, Pelosi P, et al. A trial of goal-oriented hemodynamic therapy in critically ill patients. N Engl J Med. 1995;333:1025–1032.PubMedCrossRef

15.

Hayes MA, Timmins AC, Yau E, et al. Elevation of systemic oxygen delivery in the treatment of critically ill patients. N Engl J Med. 1994;330:1717–1722.PubMedCrossRef

16.

Connors AF, Speroff T, Dawson NV, et al. The effectiveness of right heart catheterization in the initial care of critically ill patients. JAMA. 1996;276:889–897.PubMedCrossRef

17.

Harvey S, Harrison DA, Singer M, et al. Assessment of the clinical effectiveness of pulmonary artery catheters in management of patients in intensive care (PAC-Man): a randomised controlled trial. Lancet. 2005;366:472–477.PubMedCrossRef

18.

Marik PE, Baram M, Vahid B. Does the central venous pressure predict fluid responsiveness? A systematic review of the literature and the tale of seven mares. Chest. 2008;134:172–178.PubMedCrossRef

19.

Fagon JY, Chastre J, Wolff M, et al. Invasive and non-invasive strategies for management of suspected ventilator-associated pneumonia. Ann Intern Med. 2000;132:621–630.PubMed

20.

Chastre J, Wolff M, Fagon JY, et al. Comparison of 8 vs. 15 days of antibiotic therapy for ventilator-associated pneumonia in adults: a randomized trial. JAMA. 2003;290:2588–2598.PubMedCrossRef

21.

Palevsky PP, Zhang JH, O'Connor TZ, et al. Intensity of renal support in critically ill patients with acute kidney injury. N Engl J Med. 2008;359: 7–20.PubMedCrossRef

22.

van den Berghe G, Wouters P, Weekers F, et al. Intensive insulin therapy in critically ill patients. N Engl J Med. 2001;345:1359–1367.PubMedCrossRef

23.

Rivers E, Nguyen B, Havstad S, et al. Early goal-directed therapy in the treatment of severe sepsis and septic shock. N Engl J Med. 2001;345:1368–1377.PubMedCrossRef

24.

Dellinger RP, Carlet JM, Masur H, et al. Surviving Sepsis Campaign guidelines for management of severe sepsis and septic shock. Crit Care Med. 2004;32:858–873.PubMedCrossRef

25.

Dellinger RP, Levy MM, Carlet JM, et al. Surviving sepsis Campaign: international guidelines for management of severe sepsis and septic shock: 2008. Crit Care Med. 2008;36:296–327.PubMedCrossRef

26.

Burton TM. New therapy for sepsis infection raises hope but many questions (lead article). Wall St J. 2008;A1.

27.

Marik PE, Varon J. Intensive insulin therapy in the ICU: is it now time to jump off the bandwagon? Resuscitation. 2007;2007:191–193.CrossRef

28.

Annane D, Sebille V, Charpentier C, et al. Effect of treatment with low doses of hydrocortisone and fludrocortisone on mortality in patients with septic shock. JAMA. 2002;288:862–871.PubMedCrossRef

29.

Meduri GU, Headley S, Golden E, et al. Effect of prolonged methylprednisolone therapy in unresolving acute respiratory distress syndrome. A randomized controlled trial. JAMA. 1998;280:159–165.PubMedCrossRef

30.

Sprung CL, Annane D, Keh D, et al. Hydrocortisone therapy for patients with septic shock. N Engl J Med. 2008;358:111–124.PubMedCrossRef

31.

The Acute Respiratory Distress Syndrome Network. Efficacy and safety of corticosteroids for persistent acute respiratory distress syndrome. N Engl J Med. 2006;354:1671–1684.

32.

Marik PE. Critical illness related corticosteroid insufficiency. Chest. 2009;135:181–193.PubMedCrossRef

Paul Ellis MarikHandbook of Evidence-Based Critical CareSecond10.1007/978-1-4419-5923-2_3© Springer Science+Business Media, LLC 2010

3. Critical Care Medicine 101

Paul Ellis Marik¹  

(1)

Division of Pulmonary and Critical Care Medicine, Eastern Virginia Medical School, Norfolk, VA, USA

Paul Ellis Marik

Email: [email protected]

Abstract

Patients in the ICU need to be managed by doctors who can see the big picture, be able to integrate and understand the patients’ complex multi-system disease, and formulate an integrative plan that is evidence based, systematic, and is in keeping with the patients’ treatment goals and values while being consistent with reality. Intensivists are realists who provide physiologically based interventions with the goal of limiting disease and improving outcomes; voodoo and other fantasy-based treatments have no role in the ICU. This chapter reviews the concepts and basic interventions which should be addressed when admitting a generic patient to the ICU. A number of issues need to be addressed regardless of the type of ICU to which the patient is being admitted and the patient’s diagnosis.

Patients in the ICU need to be managed by doctors who can see the big picture, be able to integrate and understand the patients’ complex multi-system disease, and formulate an integrative plan that is evidence based, systematic, and is in keeping with the patients’ treatment goals and values while being consistent with reality. Intensivists are realists who provide physiologically based interventions with the goal of limiting disease and improving outcomes; voodoo and other fantasy-based treatments have no role in the ICU. This chapter reviews the concepts and basic interventions which should be addressed when admitting a generic patient to the ICU. A number of issues need to be addressed regardless of the type of ICU to which the patient is being admitted and the patient’s diagnosis.

It is important to note that no two patients are ever the same and that patients do not read medical textbooks or policies and procedures. Furthermore, patients respond differently to the same intervention. Each patient’s care must therefore be individualized based on the patient’s unique demographics, comorbidities, acute disease processes, response to physiologically based interventions, and their values and goals. Policies and procedures and bundles of care have a limited place in the ICU. Parallels are often drawn between the airline industry and the practice of medicine. In general, this is a dangerous position to take. As Southwest Airlines understands, all 737-300s are build exactly the same and respond exactly in the same way when the same set of knobs and levers are pulled; patients, however, are not 737s (they are infinitely more complex and much more unpredictable).

How an ICU Differs From Other Areas of the Hospital

An ICU is a place where patients undergo intensive and continuous physiological monitoring, where the critical care team applies physiologically based interventions and monitors the response to these interventions, which then serves as the basis for further interventions. It is therefore clear that critical care medicine can be practiced only at the bedside; office-based intensivists have no place in the ICU.

Factors to Consider When a Patient Is Admitted to the ICU

The patient’s age (chronological not physiological)1 (see Chapter 55).

Comorbidities, particularly the following:

Cardiac disease and ventricular function.

Underlying lung disease.

Baseline renal function (the baseline and current estimated GFR should be calculated on admission in all patients).*¹

Use of immunosuppressive drugs.

The diagnoses and differential diagnoses.

Is this patient septic?

Does this patient have SIRS (leaky capillaries)?

Does this patient have acute lung injury (ALI)?

What is the status of this patient’s intravascular volume? (see Chapter 8)?

Normal.

Increased.

Decreased.

Does this patient have evidence of impaired tissue/organ perfusion (see Chapter 8)?

Decreased urine output.

Cold/clammy skin.

Mottled peripheries.

Increased lactate concentration.

Hypotension.

The patients’ code status, preferences for life-supportive therapy, and goals/expectations of treatment must be determined when the patients are admitted to the ICU.

Determine the adequacy of venous access.

Communicate with the patients’ nurse and respiratory therapist.

Keep the family informed.

Measure the patients’ height and weight on admission (see Chapters 14 and 19).

Initial Generic Treatment Orders

Fluids:

State the type of fluid and the infusion rate.

Oxygenation

Nasal cannula/Venturi mask.

Initial ventilator settings:

AC rate 6–8 ml/kg Ideal Body weight (IBW).

Flow rate 60 l/min.

FiO2 100%.

PEEP 5–10 cm H2O.

ICU patients are at a high risk for deep venous thrombosis (DVT) and therefore all ICU patients require DVT prophylaxis. This should be individualized based on the patient’s risk of DVT, risk of bleeding, risk of HIT, and renal function (see Chapter 21):

Subcutaneous heparin (5,000 U BID, TID).

Subcutaneous low molecular weight heparin.

Subcutaneous fondaparinux (2.5 mg q day).

Sequential compression devices.

Combination of SCD and anti-coagulant.

Routine stress ulcer prophylaxis is not required in patients who are receiving enteral nutrition (see Chapter 32):

PPI or H2RB in those who require stress ulcer prophylaxis.

Nutrition (see Chapter 31):

Unless specifically contraindicated or the patient’s length of stay in the ICU is expected to be less than 24 h, all patients should be fed enterally once they have been resuscitated.

All patients require chlorhexidine (or equivalent) mouth wash and regular oral hygiene.2,3

All patients should be nursed head up 30° unless contraindicated for some reason (reduces risk of VAP).4

Ocular lubricant to prevent exposure keratopathy.5

Sedation should be titrated to the RASS score (see Chapter 9).

All ICU patients should be regularly screened (at least daily) for the presence of delirium using a validated delirium assessment tool (see Chapter 47).

Sedation with benzodiazepines should be avoided (see Chapters 9 and 47).

References

1.

Marik PE. Management of the Critically Ill Geriatric Patient. Crit Care Med. 2006;34(Suppl):S176–S182.PubMedCrossRef

2.

Koeman M, van der Ven AJ, Hak E, et al. Oral decontamination with chlorhexidine reduces the incidence of ventilator-associated pneumonia. Am J Respir Crit Care Med. 2006;173:1348–1355.PubMedCrossRef

3.

Chan EY, Ruest A, O’Meade M, et al. Oral decontamination for prevention of pneumonia in mechanically ventilated adults: systemic review and meta-analysis. Br Med J. 2007-doi:10.1136/bmj.39136.528160.BE.

4.

Drakulovic MB, Torres A, Bauer TT, et al. Supine body position as a risk factor for nosocomial pneumonia in mechanically ventilated patients: a randomised trial. Lancet. 1999;354:1851–1858.PubMedCrossRef

5.

Ezra DG, Chan MP, Solebo L, et al. Randomised trial comparing ocular lubricants and polyacrylamide hydrogel dressings in the prevention of exposure keratopathy in the critically ill. Intensive Care Med. 2009;35:455–461.PubMedCrossRef

Footnotes

1

*Estimated GFR (Cockcroft–Gault equation) = (140–age) (weight in kg) (0.85 if female)/ (creatinine 72)

Paul Ellis MarikHandbook of Evidence-Based Critical CareSecond10.1007/978-1-4419-5923-2_4© Springer Science+Business Media, LLC 2010

4. House Officers’ Guideline 1: Housekeeping

Paul Ellis Marik¹  

(1)

Division of Pulmonary and Critical Care Medicine, Eastern Virginia Medical School, Norfolk, VA, USA

Paul Ellis Marik

Email: [email protected]

Abstract

Intensive care units embody the miraculous advances of modern medicine. An ICU provides an environment where high-quality, compassionate, physiologically orientated, and evidence-based medicine can be practiced. The ICU is an exciting and challenging place to work and provides a remarkable learning environment. The keys to a successful rotation in the ICU are (1) teamwork and (2) a systematic, disciplined, and organized approach to patient care.

Intensive care units embody the miraculous advances of modern medicine. An ICU provides an environment where high-quality, compassionate, physiologically orientated, and evidence-based medicine can be practiced. The ICU is an exciting and challenging place to work and provides a remarkable learning environment. The keys to a successful rotation in the ICU are (1) teamwork and (2) a systematic, disciplined, and organized approach to patient care.

Admission History and Physical Examination

It is essential that a detailed and systematic history and physical examination be performed on all patients admitted to the ICU. This should include past medical and surgical history, current mediations as well as details of the current illness. The patient’s code status and the presence of advance directives should be established on admission to the ICU. The initial physical examination frequently serves as the baseline reference, and it should include a basic neurological examination (including reflexes, motor power, evaluation of mental status, and funduscopic examination). Following the history and physical examination, and review of the available laboratory data and chest radiograph, a differential diagnosis and a management plan should be formulated.

The patient’s weight and height should be measured directly with a scale and tape measure on admission to the ICU. These values should not be estimated as they are frequently wrong 1; the height and the weight are used in dosing calculations as well as estimating GFR and predicted body weight (PBW); so the correct data should be used.

Daily Examination

It is essential that the patient’s flow sheet (paper or electronic) over the last day be thoroughly reviewed and the major events of the last 24 h be documented. Most ICUs use a 24-h flow sheet which runs from midnight to midnight. Hence when reviewing and documenting the patient’s progress over the last day, the last 24-h period (midnight–midnight) as well as the progress since midnight should be reviewed. The following serves as a guideline for the daily progress note:

ALERT

It is important to be systematic and develop a template for your daily progress notes.

General

Primary and secondary diagnoses, overall condition of the patient, and events of the last 24 h.

Vital Signs (24-h Min and Max and Current)

Temperature

Blood pressure

Pulse (rate and rhythm)

Respiratory rate

Arterial saturations

Fluid balance and urine output are vitally important in the daily and ongoing evaluation of the ICU patient. The following should be recorded:

24 h in.

24 h out.

24 h urine.

Output of each drain should be noted.

Cumulative fluid balance.

6 h in.

6 h out.

6 h urine.

Additional Observations

The doses of all pressors should be documented.

The presence of all pulses and the adequacy of peripheral perfusion.

Limb symmetry and swelling (DVT).

Presence of rashes and decubitus ulcers.

The presence of all invasive lines, tubes, and devices should be noted including the duration of each central line.

The Ventilator

The ventilator is an extension of the patient and it is therefore essential that the following features be recorded (see Chapter 14):

Mode

Assist controlled

Pressure controlled

Pressure support

APRV (Airway Pressure Release Ventilation)

SIMV (Synchronised Intermittent Mandatory Ventilation)

Rate (set)

Tidal volume (Vt)

Total

Milliliters per PBW(kg)*¹(This is very NB)

Minute ventilation

FiO2

PEEP

Most recent blood gas analysis (if within past 24 h)

ALERT

Patients require a daily spontaneous breathing trial if criteria met (see Chapter 16).

Heart

Heart sounds and murmurs.

Chest

Symmetry of air entry (i.e., presence of breath sounds) and presence of rhonchi or crackles.

Abdomen

The presence of distension and tenderness (especially right upper quadrant), the type of enteral feeds, evidence of reflux, gastric residual volumes, and the presence of diarrhea (see Chapters 31 and http://38).

CNS

A focused neurological examination is essential, particularly in patients receiving hypnotic/sedative agents, and should include the following:

Level of consciousness and response to commands

Pupillary size and response

Eye movements

Limb movements: spontaneous and in response to noxious stimuli (pain)

Presence of deep tendon reflexes

ALERT

Patients require daily awakenings to determine neurological status and allow re-evaluation of sedation (see Chapters 9 and http://16).

Importance of the Daily Neurological Examination

Critically ill patients in the ICU are at risk of developing serious neurological complications including ICU psychosis, septic encephalopathy, critical illness polyneuropathy, entrapment neuropathies, compartment syndromes, cerebral edema, intracerebral hemorrhages (related to coagulopathies), cerebral ischemia (related to hemodynamic instability), and cerebral embolism. These conditions can be detected and diagnosed only by physical examination. Furthermore, these conditions may frequently be masked in patients who are sedated. If the patient does not respond to a noxious stimulus, the sedation must immediately be stopped to facilitate further neurological evaluation.

Laboratory Tests

All ICU patients require the following tests daily (if a patient does not require these tests, he/she probably does not need to be in the ICU!):

Complete blood count:

Hemoglobin.

White cell count (differential and band count).

Platelet count.

Urea and electrolytes.

Oxygenation should be assessed in all patients (usually by pulse oximetry and blood gasses when appropriate).

Ca²+, Mg, and phosphorus should be measured every 2–3 days or more frequently if clinical circumstances dictate.

All other laboratory tests should be ordered on merit; standing laboratory tests are not cost effective.

It is not cost effective to perform a complete blood count and urea and electrolyte tests more frequently than every 24 h unless special circumstances dictate, such as the following:

Diabetic ketoacidosis, hypernatremia, hyponatremia, where Na+ and K+ should be tested every 2–4 h.

In patients who are bleeding, a hematocrit should be followed no more frequently than every 6 h (it takes 72 h for the hematocrit to stabilize following blood loss).

Alert

Pay special attention to a falling platelet count (see Chapter 53)

HIT

Drug-induced thrombocytopenia

Patients with hypernatremia receiving 3% NaCl should have electrolytes followed every 1–2 h

Imaging

Daily chest X-rays are not cost effective.

Chest X-rays should be performed only on demand (as clinical circumstances dictate).2,3

Presenting on Daily Rounds

Presenting a succinct and complete summary of a patient’s status is an important skill that all clinicians must master. Due to the large volume of data, together with the rapid turnover of high-acuity patients, clear, succinct, and logical presentation is essential in the ICU.

The following schema is suggested:

Events over last 24 h

Daily exam (as outlined above)

Relevant laboratory results

Review of medications (all)

Assessment

Plan

Clinical Pearls

If you do not understand something, ask!

If unsure, don’t do it!

Ask the primary ICU nurse; she(he) knows best.

References

1.

Bloomfield R, Steel E, MacLennan G, et al. Accuracy of weight and height estimation in an intensive care unit: implications for clinical practice and research. Crit Care Med. 2006;34:2153–2157.PubMedCrossRef

2.

Clec’h C, Simon P, Hamdi A, et al. Are daily routine chest radiographs useful in critically ill, mechanically ventilated patients? A randomized study. Intensive Care Med. 2008;34:262–270.

3.

Graat ME, Kroner A, Spronk PE, et al. Examination of daily routine chest radiographs in a mixed medical–surgical intensive care unit. Intensive Care Med. 2007;33:639–644.PubMedCrossRef

Footnotes

1

*Lung volume is indexed to predicted body weight (PBW) which is dependent on sex and height:

Paul Ellis MarikHandbook of Evidence-Based Critical CareSecond10.1007/978-1-4419-5923-2_5© Springer Science+Business Media, LLC 2010

5. Admission–Discharge Criteria

Paul Ellis Marik¹  

(1)

Division of Pulmonary and Critical Care Medicine, Eastern Virginia Medical School, Norfolk, VA, USA

Paul Ellis Marik

Email: [email protected]

Abstract

The advanced life support technology which can be provided in the ICU is intended to provide temporary physiological support for patients with potentially reversible organ failure or dysfunction.¹ In general, only patients who have a reasonable prospect of recovery should be treated in the ICU.

Admission Criteria

The advanced life support technology which can be provided in the ICU is intended to provide temporary physiological support for patients with potentially reversible organ failure or dysfunction.1 In general, only patients who have a reasonable prospect of recovery should be managed in the ICU. The merits of each potential ICU admission should be assessed on an individual basis, and taking the following factors into account:

The patient’s wishes or advance directives regarding life support treatment

The patients underlying disease(s) and physiological function

The severity and reversibility of the patient’s acute condition

The patient’s baseline function and level of independence

When the reversibility and prognosis of a patient’s condition is uncertain, a time-limited therapeutic trial in the ICU may be justified. A DNR order does not preclude a patient from being admitted to the ICU; this is a specific instruction not to perform advanced cardiac life support (ACLS) once the patient’s heart has stopped (i.e., once the patient has died). Patients with advanced chronic disease, patients with terminal illnesses, and patients who have suffered a catastrophic insult should be admitted to the ICU only if there is a reasonable chance that the patient may benefit from aggressive management in the ICU and the patient or surrogate is prepared to accept the burden (i.e., pain, suffering) that such therapy may incur. It should be appreciated that death is the only certainty of life, and that the ICU is not a halfway station between life on earth and the hereafter; this implies that not all dying patients need (or will benefit from) admission to an ICU.

Once a patient is admitted to the ICU the appropriateness of continuing care in the ICU should be evaluated in an ongoing fashion; the fact that aggressive life-supportive therapy has been provided to a patient does not imply that it cannot be withdrawn. Patients should only remain in the ICU as long as they continue to derive benefit from the physiological support provided in the ICU. When all the ICU beds are filled, the ICU/Critical Care Director or his designee will have the responsibility to admit/discharge patients from these units. Triage decisions should be made explicitly, fairly, and justly. Ethnic origin, race, sex, social status, sexual preference or financial status should not be considered in triage decisions. Triage decisions may be made without patient, surrogate, or attending physician consent.

In evaluating the appropriateness of an admission to the ICU, the priority of the admission as well as the disease-specific or physiological indications for admission (as outlined below) should be determined.

Prioritization of Potential ICU Admissions

This system defines those patients that will benefit most (priority 1) to those that will not benefit at all (priority 4) from admission to an ICU.

Priority 1

These are critically ill, unstable patients in need of intensive treatments and monitoring that cannot usually be provided outside of the ICU. Examples of such treatments include ventilator support, continuous titration of vasoactive drug infusion. These patients have no limits placed on the extent of therapy they are to receive. Illustrative case types include postoperative or acute respiratory failure patients requiring mechanical ventilatory support and shock or hemodynamic instability requiring invasive monitoring and/or titrated vasoactive drugs.

Priority 2

These are patients that require the intensive monitoring services of an ICU and are at risk to require immediate intensive treatment. No limits are placed on the extent of therapy these patients are to receive. Examples of these patients include patients with underlying heart, lung, renal, or central nervous system disease who have an acute severe medical illness or have undergone major surgery, and those patients requiring invasive hemodynamic monitoring.

Priority 3

These are critically ill, unstable patients whose previous state of health, underlying disease, or acute illness reduces the likelihood of recovery and therefore benefit from ICU treatment. These patients may receive intensive treatment to relieve acute illness but therapeutic efforts may stop short of measures such as intubation or cardiopulmonary resuscitation. Examples include patients with metastatic malignancy complicated by infection, pericardial tamponade or airway obstruction, or patients with end-stage heart or lung disease complicated by a severe acute illness.

Priority 4

These are patients who are generally not appropriate for ICU admission. Admission of these patients should be on an individual basis, under unusual circumstances and at the discretion of the ICU attending physician/ICU director. These patients can be placed in the following categories:

Little or no additional benefit from ICU care (compared to non-ICU care) based on low risk of active intervention that could not safely be administered in a non-ICU setting (i.e., too well to benefit from ICU care). These include patients with peripheral vascular surgery, hemodynamically stable diabetic ketoacidosis, conscious drug overdose, mild congestive heart failure.

Patients with terminal, irreversible illness who face imminent death (i.e., too sick to benefit from ICU care). This includes patients with severe irreversible brain damage, irreversible multi-organ system failure, metastatic cancer unresponsive to chemotherapy and/or radiation therapy (unless the patient is on a specific treatment protocol), brain-dead non-organ donors, patients in a persistent vegetative state, patients who are permanently unconscious.

This group includes patients with decision-making capacity who decline intensive care and/or invasive monitoring and who elect to receive comfort care only. This group excludes brain-dead patients who are organ donors or potential organ donors (these patients require intensive monitoring and/or treatment in an ICU).

Transfer from Another Hospital: Variable Priority

The priority of transfers from other hospitals should be based on the current ICU census as well as the nature of the patient’s acute condition and the risks of interhospital transfer. Consent for transfer must be obtained from the patient or his/her surrogate by the transferring attending physician prior to transfer.

Disease-Specific Indications for ICU Admission

Cardiovascular System

Acute myocardial infarction (AMI) complicated by ongoing pain, arrhythmias, CHF, or hemodynamic instability

Patients suffering an AMI who are candidates for or have received reperfusion therapy

Unstable angina

Cardiogenic shock

Acute congestive heart failure with respiratory failure and/or requiring hemodynamic support

Hypertensive emergencies, i.e., accelerated hypertension with encephalopathy, chest pain, pulmonary edema, aortic dissection, or eclampsia

Pulmonary System

Acute respiratory failure requiring emergent ventilatory support, including non-invasive positive-pressure ventilation

Severe asthma, with FEV1 or peak flow <40% predicted, pulsus paradoxus >18 mmHg, pneumothorax or pneumomediastinum, PaCO2 >40 mmHg, or an exhausted patient

Hemodynamically unstable patients with pulmonary emboli and/or patients who are candidates for thrombolytic therapy

Neurological Disorders

Patients suffering a CVA who are candidates for or have received thrombolytic therapy [i.e., within a 3 (4.5 h)-h window following the onset of the CVA] and patients with cerebellar or brain-stem CVAs

Central nervous system or neuromuscular disorders with deteriorating neurological or ventilatory function

Patients with subarachnoid hemorrhage (Hunt and Hess grades I–IV)

Drug Ingestion and Drug Overdose

Hemodynamically unstable drug ingestion

Drug ingestion with significantly altered mental status with inadequate airway protection

Seizures following drug ingestion

Drug ingestion requiring mechanical ventilation

Drug ingestion requiring acute hemodialysis/hemoperfusion

Gastrointestinal Disorders

Gastrointestinal bleeding from any source with

Hemodynamic instability:

Systolic arterial pressure <100 mmHg

Pulse rate >120 beats/min

Postural hypotension after 1,000 ml of fluid resuscitation (but excluding postural hypotension on presentation alone)

Hypotension requiring pressors

Ongoing bleeding (bright red blood on NG aspirate; red or maroon blood per rectum)

Rebleeding

Erratic mental status

Unstable comorbid disease

Coagulopathy (INR >1.6 and/or PTT >40 s)

Fulminant hepatic failure

Chronic liver failure with

Grade III/IV encephalopathy

Oliguria

GI bleeding

Acute hemorrhagic pancreatitis (three or more Ranson criteria)

Endocrine

Diabetic ketoacidosis with severe acidosis, hemodynamic instability, or altered mental status

Hyperosmolar state with coma and/or hemodynamic instability

Thyroid storm or myxedema coma

Severe hyponatremia, hypernatremia, or hypercalcemia with altered mental status

Hyperkalemia, severe and acute

Adrenal crisis

Renal Disorders

Patients who require acute emergent dialysis

Severe hypertension

Pulmonary edema

Hyperkalemia

Postoperative Care

Postoperative patients requiring hemodynamic monitoring, ventilatory support, treatment of hemodynamic instability or airway monitoring

Neurosurgical patients requiring hemodynamic monitoring or aggressive titrated treatment of intracranial hypertension and vasospasm, etc.

Miscellaneous

Septic shock or sepsis syndrome requiring hemodynamic monitoring or hemodynamic or respiratory support.

Physiological Indication for Icu Admission

Apical pulse <40 or >150 beats/min (>130 beats/min if age >60 years)

Mean arterial pressure (MAP) <60 mmHg after adequate fluid resuscitation (2,000 ml) or the need for vasoactive agents to maintain a MAP >60 mmHg

Diastolic blood pressure >110 mmHg and one of the following:

Pulmonary edema

Encephalopathy

Myocardial ischemia

Dissecting aortic aneurysm

Eclampsia or pre-eclampsia (diastolic >100 mmHg)

Subarachnoid hemorrhage (diastolic >100 mmHg).

Respiratory rate >35 breaths/min (sustained) and respiratory distress

PaO2 <55 mmHg with FiO2 ≥ 0.4 (acute)

Serum potassium >6.5 mEq/l (acute)

pHa <7.2 or >7.6 (diabetic ketoacidosis pHa <7.0)

Serum glucose >800 mg/dl

Serum calcium >15 mg/dl

Temperature (core) <32°C

Discharge Criteria

In order to maximize the efficient use of ICU resources, the discharge process should be ongoing and continuous. Once admitted, it may be possible to determine whether a patients is too well to benefit or too sick to benefit from continued intensive care (see Chapter 62). Patients should be discharged from the ICU when it can be determined that the patient is no longer benefitting from being in the ICU. The discharge process should be a collaborative one between the intensivist, the primary care physician or surgeon, and the nursing staff to assure that the needs of the patients can be met by the receiving unit. General criteria for ICU discharge have been met when the need for intensive care is no longer present because of the following:

The indication for initial or continued treatment has reverted spontaneously or with therapy.

Therapy provided has not reversed the reason for admission and little benefit will be attained from continued intensive therapy.

The need for intensive monitoring is no longer present.

The patient has responded to treatment but the long-term prognosis is such that continuing further care is unacceptable to the patient or his surrogate.

Reference

1.

Guidelines for intensive care unit admission, discharge, and triage. Task Force of the American College of Critical Care Medicine, Society of Critical Care Medicine. Crit Care Med. 1999;27:633–638.CrossRef

Paul Ellis MarikHandbook of Evidence-Based Critical CareSecond10.1007/978-1-4419-5923-2_6© Springer Science+Business Media, LLC 2010

6. House Officers’ Guidelines 2: Procedures

Paul Ellis Marik¹  

(1)

Division of Pulmonary and Critical Care Medicine, Eastern Virginia Medical School, Norfolk, VA, USA

Paul Ellis Marik

Email: [email protected]

Abstract

• The tradition of See one, Do one, Teach one can no longer be condoned. The safety and well being of the patient is one’s overriding concern.

• If you do not know how to do it, do not do it!

Alert

The tradition of See one, Do one, Teach one can no longer be condoned. The safety and well being of the patient is one’s overriding concern.

If you do not know how to do it, do not do it!

Before doing a procedure, make sure that you have all the equipments required.

Make sure you know how to get out of trouble should the procedure go wrong.

If you fail after 2–3 attempts at the procedure, stop. Ask a more experienced operator for help.

Check the platelet count, PTT, and INR before any invasive procedure (see Chapters 52 and 53).

As a general rule the risk of bleeding is related to the skill of the operator rather than the ability of the blood to clot (however this helps).

Patients receiving therapeutic anti-coagulants tend to bleed; stop anti-coagulants prior to the procedure.

Obtain informed consent from the patient (or surrogate), unless an emergency. Explain the benefits and risks (including death). See Chapter 65.

Murphy’s First Law of Procedures:

Nature sides with the hidden flaw.

Murphy’s Second Law of Procedures:

If a procedure can go wrong, it will go wrong usually at the most inopportune time.

Murphy’s Third Law of Procedures:

If a patient can bleed, he/she will bleed.

Murphy’s Fourth Law of Procedures:

Never persuade a patient to agree to a procedure that they have declined or are hesitant about; these are the patients that will suffer a complication.

Murphy’s Fifth Law of Procedures:

Never force a device into a patient; if it does not go in easily, it will go into the wrong place.

Central Venous Access

Most ICU patients require a central line. Indications include the following1 – 9:

Use of any vasopressor agent. Dopamine, epinephrine, and norepinephrine infusion should never run through a peripheral line.

Multiple mediations, infusions, antibiotics, etc.

Patient requiring volume/blood resuscitation with inadequate peripheral venous access.

Placement:

A fully stocked procedure cart is highly recommended.

ICU nurse should be at bedside to assist (and observe) the operator.

Full body drape is recommended.

An antibiotic-/anti-microbial-coated catheter is recommended in units which have a high baseline incidence of catheter-related bloodstream infection I (>5/1,000 catheter days).

Use a chuck (absorptive pad) to prevent covering the bed in blood.

Clean up your mess after you are completed; do not leave it up to the nurse.

Site of placement:

First choice should depend on patient’s body habitus, existing and previous lines, and your degree of comfort with each site.

Ultrasound guidance is highly recommended for placement of internal jugular (IJ) lines and visualization of the inguinal anatomy in obese patients.

The femoral site is suggested in highly coagulopathic patients, in emergency situations, in patients with severe bullous lung disease, etc.

The femoral site is compressible should the artery be accidentally stuck (as opposed to the IJ or the subclavian).

It is nearly impossible to cause a pneumothorax or a hemothorax when placing a femoral line.7,8 Caution should be used when placing an IJ or a subclavian line in patients with ALI/ARDS or severe COPD; a pneumothorax can be fatal.

Catheter-related bloodstream infection (see Chapter 11). As a general rule the risk of CRBI is lowest for a subclavian CVC followed by an IJ and then a femoral catheter.

Femoral catheters have a significantly higher risk of thrombosis (2% vs. 20%).10,11 Aggressive DVT prophylaxis is indicated in these patients (see Chapter 21).

A CXR is required after an IJ/subclavian to confirm correct placement and to exclude a pneumothorax.

Document procedure in patient’s chart (with date and time).

As a general rule, if you think a central venous catheter is infected, it is better to remove and place at a new site rather than to replace over a guidewire. A guidewire exchange is acceptable in patients with limited venous access; however, the catheter tip must be cultured and the line removed if the cultures are positive (>10 cfu).

Subclavian Vein Catheterization

Advantages: Consistent identifiable landmarks, easier long-term catheter maintenance, relatively high patient comfort.

Disadvantages:

Pneumothorax (1–2%).

Subclavian artery puncture (1%).

Difficult to perform under ultrasound guidance.

Contraindications:

Subclavian puncture is a relative contraindication in patients with a coagulopathy and/or a pulmonary compromise (dependent on the expertise of the operator).

Anatomy: It is continuation of axillary vein, beginning at the outer border of first rib, extending 3–4 cm along the undersurface of clavicle, and joining ipsilateral internal jugular vein behind the sternoclavicular joint.

Position (most important): The patient is placed supine with arms at the side and head turned to the opposite side. Trendelenburg position (15–30°), with a small bedroll placed between the shoulder blades.

Infraclavicular approach (blind):

Identify the clavicle, the suprasternal notch, and the acromium–clavicular junction.

The operator’s position is next to patient’s ipsilateral shoulder. Feel along the inferior border of the clavicle moving from medial to lateral until you feel a give in the tissue resistance. This point is approximately at the junction between the medial and the middle thirds of the clavicle and at the point of the first S bend in the clavicle.

The skin and the subcutaneous tissue should now be infiltrated with 1% lidocaine. The thumb of the left hand is now placed in the suprasternal notch to serve as a landmark.

A 2 3/4-in., 14-gauge needle is mounted on a syringe and directed cephalad from the point until the tip abuts under the clavicle. With the needle hugging the inferior edge of clavicle the needle is now advanced toward the suprasternal notch (the thumb of your left hand). The needle is advanced until the subclavian vein is entered.

Internal Jugular Vein Catheterization

Advantages: Minimal risk for pneumothorax, preferred in patients with hyperinflation and those receiving mechanical ventilation.

Disadvantages: Carotid artery puncture (2–10%) with blind technique.

Anatomy: It emerges from the base of the skull through jugular foramen and courses posterolateral to the internal carotid artery in the carotid sheath and runs beneath the sternocleidomastoid muscle.

Position is supine with 15° Trendelenburg and the head turned gently to the opposite side.

Central approach (blind):

The skin is punctured at the apex of the triangle formed by the two muscle bellies of sternocleidomastoid muscle and the clavicle, at a 30–45° angle with the frontal plane and directed at the nipple on the same side.

Ultrasound approach:

The IJ vein is typically anterior and lateral to the artery.

The IJ vein can be distinguished by the fact that the vein is compressible, non-pulsatile, and distensible by the Trendelenburg position.

Screening US to assess the degree of overlap of carotid artery by the IJ vein, the compressibility of the vein, and the presence of internal echoes that may signify clot.

Color Doppler can be used to visualize distinct arterial and venous pulsations (color dependent on direction of the probes in relation to flow and not the color of the blood).

Once the appropriate site is selected, the site is sterilized and draped with full barrier precautions.

Using US to mark the skin and proceeding without real-time guidance is not recommended.

The US probe is placed in a sterile sheath; this step requires an assistant. Sterile gel must be placed on the probe and the outside of the sheath.

As the procedure is performed in real time, a finder needle is not required.

In the one-handed method, the operator controls the ultrasound probe with the non-dominant hand and the needle with the dominant hand.

Passage of the introducer needle into the IJ vein can be performed either with a transverse (short axis) view or a longitudinal (long axis) view.

The primary advantage of the longitudinal view is that it allows better visualization of the advancing needle tip.

Once the IJ vein is entered with the introducer, the US probe is placed on the field and the typical Seldinger technique used to place the central venous catheter.

Femoral Vein Catheterization

Advantages: Safe, easily accessible, do not need Trendelenburg. Safe to perform in patients with a coagulopathy.

Disadvantages: Limits flexion of leg at the hip, increased risk of CRBI and thrombosis.

Anatomy: It is the continuation of popliteal vein and becomes external iliac vein at inguinal ligament. It lies medial to the femoral nerve and the femoral artery in the femoral sheath at the inguinal ligament.

Technique:

Clean and shave the area. The patient is placed supine with the leg extended and slightly abducted at hip.

Palpate for the femoral arterial pulsation; the site of puncture is 1–1.5 cm medial to the femoral arterial pulsation below the inguinal ligament. In a patient with no palpable femoral pulse, it is 1–1.5 cm medial to the junction of medial third and lateral two-thirds of a line joining the anterior superior iliac spine and the pubic tubercle.

A 14-gauge needle is placed at the site of puncture and advanced at a 45–60° angle to the frontal plane with the tip pointed cephalad.

After obtaining return of venous blood, the syringe and the needle are depressed to skin level and free aspiration of blood reconfirmed.

ALERT

Do not place a femoral line in a kidney transplant patient.

Do not place a central line on the same side as a dialysis fistula (femoral or subclavian CVC).

Do not remove a CVC (subclavian or IJ) in an upright patient (may cause air embolism).

Complications of Central Venous Access

Catheter-related bloodstream infection (see Chapter 11).

Local infection.

Local bleeding.

Venous air embolism :

Entry of air into the central venous system through the catheter can be fatal.

It is best prevented by positioning the patient in 15° Trendelenburg position during catheter insertion.

It will manifest as tachypnea, wheezing, hypotension, and mill wheel murmur over precordium.

The patient should be immediately turned onto his/her left side in the Trendelenburg position and air aspirated after advancing the catheter into the right ventricle.

Venous thrombosis (see Chapter 21).

Pneumothorax and/or hemothorax:

Occurs due to injury to pleura and underlying lung.

Small pneumothorax can be observed, but medium to large pneumothoraces will require chest tube insertion.

As a general rule, all intubated patients with a pneumothorax require a chest tube.

Arterial puncture:

If occurs, apply sufficient pressure for at least 10 min.

Arterial puncture may be confirmed by pulsatile flow and high hydrostatic pressure.

Catheter tip migration and perforation of free wall of cardiac chamber.

Vascular erosions:

Uncommon.

Typically occur 1–7 days after catheter insertion.

Cause sudden dyspnea with new pleural effusion or hydromediastinum on chest radiograph.

More common with left-sided catheter placement

Occlusion of catheter: It is common. Best treated by replacement of catheter.

Retained catheter fragment: Catheter tips may get sheared off by traction on beveled tip of inserting needle or by fracture of catheter due to improper fixation and excessive movement.

Inadvertent venous catheter placement: Placement into the internal jugular vein or the opposite subclavian vein from subclavian vein approach is not uncommon.

Arterial Lines

In most patients, blood pressure can be monitored using the traditional time-honored technique used by Florence Nightingale, RN, namely using an adequately sized blood pressure cuff and a mercury or an automated manometer.

Indications for an arterial line include the following:

Ongoing shock and hemodynamic instability.

Frequent requirement for arterial blood gas analysis.

Patients requiring frequent titration of vasoactive agents.

To measure pulse pressure variation and for pulse contour analysis (see Chapter 8).

Preferred site:

My preference is the femoral artery unless the patient has severe peripheral arterial disease. The femoral artery was placed superficially in the groin to make the intensivist’s life easier!

The radial artery is okay; however, check for the patency of the ulnar artery and monitor perfusion of the thumb.

Naso/Orogastric Tubes

Almost all ICU patients require a naso/orogastric tube or a feeding tube.12–16

As a general rule, an orogastric tube is preferred over a nasogastric tube to limit the risk of sinusitis.

In patients who require endotracheal intubation, it is preferable to place the ET tube before the NG/OG tube.

In patients with previous trans-sphenoidal surgery, maxilla-facial and/or facial fracture placement should always be performed under direct vision (not blind) by an operator experienced in this technique (e.g., ENT surgeon).

All intubated patients require an OG tube:

Decompresses the stomach (air and gastric contents).

Allows early enteral feeding (see Chapter 31).

Allows PO medication.

Allows assessment of gastric residuals.

Placement:

Tell the patient what you are doing (if awake).

Ask them to swallow as the tube goes in.

Lubricate the end of the tube with surgilube.

Flex the neck.

Gently push the tube past the naso/oropharynx and into the esophagus.

Never force the tube.

If the patient coughs, remove and attempt again.

If you are having difficulty, it may help to soften the tube with warm water.

In those difficult cases, placement may be achieved under direct vision either using a standard or a fiber-optic laryngoscope. An experienced intensivist, a surgeon or an ENT is required for this maneuver.

Confirming placement in the stomach:

Inject air and auscultate over the epigastrium (Whoosh test).

Aspirate; stomach contents or bile confirms placement.

An abdominal (or half–half) X-ray is required in all patients to confirm placement.

Feeding Tubes

Small bore-feeding tubes are designed to go into the lung; This is a bad thing.7,18

Feeding tubes should not be placed by those inexperienced in the technique.

Devices that allow accurate placement using electromagnetic guidance technology are currently available (GPS for the feeding tube). This method is highly recommended.18

In patients with lesions of the