Equipment review: the success of early goal-directed therapy for septic shock prompts evaluation of current approaches for monitoring the adequacy of resuscitation

Anesthetic management of a pediatric patient with pulmonary arteriovenous fistula undergoing liver transplantation - a case report

For patients with HPS who require anesthesia for a procedure, HPV should be maintained to prevent worsening hypoxemia. Here, the case of a 9-yr-old girl who was scheduled for a living donor liver transplantation is presented. The patient suffered from end-stage liver disease with HPS due to biliary atresia, which contributed to the development of a diffuse pulmonary AVF. Consequently, anesthetic management of this patient involved two different types of pulmonary shunt. It is important to maintain HPV, not only to prevent worsening of the hypoxia caused by HPS but also to inhibit an increase in PVR that could cause an increase of shunt flow through the pathological fistula. A TIVA technique was performed, and a nitrous oxide inhaler was prepared in case of a possible increase in PVR during the reperfusion period. There were no adverse events during the operation. Thus, anesthesiologists should be aware of the pathophysiological status of HPS and its potential to progress to a pulmonary AVF in order to meticulously determine an anesthesia plan that accounts for the hypoxia and PVR that are associated with HPS.

Early goal-directed therapy in severe sepsis and septic shock: insights and comparisons to ProCESS, ProMISe, and ARISE

Prior to 2001 there was no standard for early management of severe sepsis and septic shock in the emergency department. In the presence of standard or usual care, the prevailing mortality was over 40-50 %. In response, a systems-based approach, similar to that in acute myocardial infarction, stroke and trauma, called early goal-directed therapy was compared to standard care and this clinical trial resulted in a significant mortality reduction. Since the publication of that trial, similar outcome benefits have been reported in over 70 observational and randomized controlled studies comprising over 70,000 patients. As a result, early goal-directed therapy was largely incorporated into the first 6 hours of sepsis management (resuscitation bundle) adopted by the Surviving Sepsis Campaign and disseminated internationally as the standard of care for early sepsis management. Recently a trio of trials (ProCESS, ARISE, and ProMISe), while reporting an all-time low sepsis mortality, question the continued need for all of the elements of early goal-directed therapy or the need for protocolized care for patients with severe and septic shock. A review of the early hemodynamic pathogenesis, historical development, and definition of early goal-directed therapy, comparing trial conduction methodology and the changing landscape of sepsis mortality, are essential for an appropriate interpretation of these trials and their conclusions.

Early goal-directed therapy in pediatric septic shock: comparison of outcomes "with" and "without" intermittent superior venacaval oxygen saturation monitoring: a prospective cohort study*

OBJECTIVE

To evaluate the effect of intermittent central venous oxygen saturation monitoring (ScvO(2)) on critical outcomes in children with septic shock, as continuous monitoring may not be feasible in most resource-restricted settings.

DESIGN

Prospective cohort study.

SETTING

PICU of a tertiary care teaching hospital.

PATIENTS

Consecutive children younger than 17 years with fluid refractory septic shock admitted to our ICU from November 2010 to October 2012 were included.

INTERVENTIONS

Enrolled children were subjected to subclavian/internal jugular catheter insertion. Those in whom it was successful formed the "exposed" group (ScvO(2) group), whereas the rest constituted the control group (no ScvO(2) group). In the former group, intermittent ScvO(2) monitoring at 1, 3, and 6 hours was used to guide resuscitation, whereas in the latter, only clinical variables were used.

MEASUREMENTS AND MAIN RESULTS

The major outcomes were in-hospital mortality and achievement of therapeutic goals within first 6 hours. One hundred twenty children were enrolled in the study-63 in the ScvO(2) group and 57 in the no ScvO(2) group. Baseline characteristics including the organ dysfunction and mortality risk scores were comparable between the groups. Children in the ScvO(2) group had significantly lower in-hospital mortality (33.3% vs 54%; relative risk, 0.61; 95% CI, 0.4, 0.93; number needed to treat, 5; 95% CI, 3, 27). A greater proportion of children in exposed group achieved therapeutic endpoints in first 6 hours (43% vs 23%, p = 0.02) and during entire ICU stay (71% vs 51%, p = 0.02). The mean number of dysfunctional organs was also significantly lesser in ScvO(2) group in comparison with no ScvO(2) group (2 vs 3, p < 0.001).

CONCLUSION

Early goal-directed therapy using intermittent ScvO(2) monitoring seemed to reduce the mortality rates and improved organ dysfunction in children with septic shock as compared with those without such monitoring.

Increasing use of less-invasive hemodynamic monitoring in 3 specialty surgical intensive care units: a 5-year experience at a tertiary medical center

INTRODUCTION

Less-invasive hemodynamic monitoring (eg, esophageal doppler monitoring [EDM] and arterial pressure contour analysis, FloTrac) is increasingly used as an alternative to pulmonary artery catheters (PACs) in critically ill intensive care unit (ICU).

HYPOTHESIS

The decrease in use of PACs is not associated with increased mortality.

METHODS

Five-year retrospective review of 1894 hemodynamically monitored patients admitted to 3 surgical ICUs in a university-affiliate, tertiary care urban hospital. Data included the number of admissions, diagnosis-related group discharge case mix, length of stay, insertion of monitoring devices (PAC, EDM, and FloTrac probes), administered intravenous vasoactive agents (β-predominant agonists--dobutamine, epinephrine, and dopamine; vasopressors--norepinephrine and phenylephrine), and mortality. Data from hospital administrative databases were compiled to create patient characteristic and monitoring variables across a 5-year time period, 2005 to 2009 inclusive. Chi-square for independent proportions, 1-way analysis of variance, and Kruskal-Wallis tests were used; tests for trend were conducted. An α level of .05 was considered significant. Statistical Package for the Social Sciences v14 was used for all statistical testing.

RESULTS

There was a significant change in the type of hemodynamic monitors inserted in 2 of the 3 surgical ICUs (in the general surgery and neurointensive care but not in the cardiac ICU) from PACs to less-invasive devices (FloTrac or EDM) during the 5-year study period (P < .001). There was no change in mortality rate over the time period (P = .492). There was an overall increase in the proportion of monitored patients who received intravenous vasoactive agents (P < .001) with a progressive shift from β-agonists to vasopressors (P < .002). Multivariate analyses indicated that age, case mix, and use of vasoactive agents were all independent predictors of inhospital mortality (P = .001) but that type of monitoring was not (P = .638).

CONCLUSIONS

In a 5-year period, the decreased insertions of PACs were replaced by increased utilization of less-invasive hemodynamic monitoring devices. This change in practice did not adversely impact mortality.

Residents and ICU nurses get reliable static and dynamic haemodynamic assessments with aortic oesophageal Doppler

BACKGROUND

Aortic oesophageal Doppler (ODM) allows continuous non-invasive haemodynamic monitoring. We tested to confirm if residents and nurses were able to reposition oesophageal probe (OP), obtain aortic blood flow of good quality and so perform reliable static and dynamic haemodynamic assessments.

METHODS

Prospective observational study assessing ODM measurements were obtained by six residents and three nurses after they have participated in training. Measured (aortic diameter) and calculated haemodynamic data [indexed stroke volume (SVI), cardiac index] were directly obtained from ODM, after residents and nurses repositioned the OP. In a second group of patients, we tested the ability of residents and nurses to detect rapid haemodynamic changes after a passive leg raising. SVI comparison was the primary end point. Statistical analysis was performed using the method of Bland and Altman.

RESULTS

Sixty-six haemodynamic measurements were performed on 42 patients. Mean bias for SVI between the skilled physician and residents, and between the skilled physician and nurses were -0.9 ± 5.2 ml/m(2) (P = 0.15), with a percentage error of 31%, and 0.9 ± 5.1 ml/m(2) (P = 0.14), with a percentage error of 33%, respectively. There was an excellent correlation for SVI between the physician and residents (r = 0.9; P < 0.0001) and between the physician and nurses (r = 0.9; P < 0.0001). Induced changes in SVI measured by residents and nurses strongly followed those of our skilled physician.

CONCLUSION

Residents and nurses get reliable static and dynamic haemodynamic assessments with ODM compared to our skilled physician.

Review article: Part one: Goal-directed resuscitation--which goals? Haemodynamic targets

The use of appropriate resuscitation targets or end-points may facilitate early detection and appropriate management of shock. There is a fine balance between oxygen delivery and consumption, and when this is perturbed, an oxygen debt is generated. In this narrative review, we explore the value of global haemodynamic resuscitation end-points, including pulse rate, blood pressure, central venous pressure and mixed/central venous oxygen saturations. The evidence supporting the reliability of these parameters as end-points for guiding resuscitation and their potential limitations are evaluated.

Outcome effectiveness of the severe sepsis resuscitation bundle with addition of lactate clearance as a bundle item: a multi-national evaluation

Introduction

Implementation of the Surviving Sepsis Campaign (SSC) guidelines has been associated with improved outcome in patients with severe sepsis. Resolution of lactate elevations or lactate clearance has also been shown to be associated with outcome. The purpose of the present study was to examine the compliance and effectiveness of the SSC resuscitation bundle with the addition of lactate clearance.

Methods

This was a prospective cohort study over 18 months in eight tertiary-care medical centers in Asia, enrolling adult patients meeting criteria for the SSC resuscitation bundle in the emergency department. Compliance and outcome results of a multi-disciplinary program to implement the Primary SSC Bundle with the addition of lactate clearance (Modified SSC Bundle) were examined. The implementation period was divided into quartiles, including baseline, education and four quality improvement phases.

Results

A total of 556 patients were enrolled, with median (25th to 75th percentile) age 63 (50 to 74) years, lactate 4.1 (2.2 to 6.3) mmol/l, central venous pressure 10 (7 to 13) mmHg, mean arterial pressure (MAP) 70 (56 to 86) mmHg, and central venous oxygen saturation 77 (69 to 82)%. Completion of the Primary SSC Bundle over the six quartiles was 13.3, 26.9, 37.5, 45.9, 48.8, and 54.5%, respectively (P <0.01). The Modified SSC Bundle was completed in 10.2, 23.1, 31.7, 40.0, 42.5, and 43.6% patients, respectively (P <0.01). The ratio of the relative risk of death reduction for the Modified SSC Bundle compared with the Primary SSC Bundle was 1.94 (95% confidence interval = 1.45 to 39.1). Logistic regression modeling showed that the bundle items of fluid bolus given, achieve MAP >65 mmHg by 6 hours, and lactate clearance were independently associated with decreased mortality - having odds ratios (95% confidence intervals) 0.47 (0.23 to 0.96), 0.20 (0.07 to 0.55), and 0.32 (0.19 to 0.55), respectively.

Conclusions

The addition of lactate clearance to the SSC resuscitation bundle is associated with improved mortality. In our study patient population with optimized baseline central venous pressure and central venous oxygen saturation, the bundle items of fluid bolus administration, achieving MAP >65 mmHg, and lactate clearance were independent predictors of outcome.

Implementing a collaborative protocol in a sepsis intervention program: lessons learned

The objective of this prospective cohort study was to see the effect of the implementation of a Sepsis Intervention Program on the standard processes of patient care using a collaborative approach between the Emergency Department (ED) and Medical Intensive Care Unit (MICU). This was performed in a large urban tertiary-care hospital, with no previous experience utilizing a specific intervention program as routine care for septic shock and which has services and resources commonly available in most hospitals. The study included 106 patients who presented to the ED with severe sepsis or septic shock. Eighty-seven of those patients met the inclusion criteria for complete data analysis. The ED and MICU staff underwent a 3-month training period followed by implementation of a protocol for sepsis intervention program over 6 months. In the first 6 months of the program's implementation, 106 patients were admitted to the ED with severe sepsis and septic shock. During this time, the ED attempted to initiate the sepsis intervention protocol in 76% of the 87 septic patients who met the inclusion criteria. This was assessed by documentation of a central venous catheter insertion for continuous SvO(2) monitoring in a patient with sepsis or septic shock. However, only 48% of the eligible patients completed the early goal-directed therapy (EGDT) protocol. Our data showed that the in-hospital mortality rate was 30.5% for the 87 septic shock patients with a mean APACHE II score of 29. This was very similar to a landmark study of EGDT (30.5% mortality with mean APACHE II of 21.5). Data collected on processes of care showed improvements in time to fluid administration, central venous access insertion, antibiotic administration, vasopressor administration, and time to MICU transfer from ED arrival in our patients enrolled in the protocol versus those who were not. Further review of our performance data showed that processes of care improved steadily the longer the protocol was in effect, although this was not statistically significant. There was no improvement in secondary outcomes, including total length of hospital stay, MICU days, and mortality. Implementation of a sepsis intervention program as a standard of care in a typical hospital protocol leads to improvements in processes of care. However, despite a collaborative approach, the sepsis intervention program was underutilized with only 48% of the patients completing the sepsis intervention protocol.

Cardiac index measurements by transcutaneous Doppler ultrasound and transthoracic echocardiography in adult and pediatric emergency patients

INTRODUCTION

Non-invasive hemodynamic monitoring may facilitate resuscitation in critically ill patients. Validation studies examining a transcutaneous Doppler ultrasound technology, USCOM-1A, using pulmonary artery catheter as the reference standard showed varying results. In this study, we compared non-invasive cardiac index (CI) measurements by USCOM-1A with transthoracic echocardiography (TTE).

METHODS

This study was a prospective, observational cohort study at a university tertiary-care emergency department, enrolling a convenience sample of adult and pediatric patients. Paired measures of CI, stroke volume index (SVI), aortic outflow tract diameter (OTD), velocity time integral (VTI) were obtained using USCOM-1A and TTE. Pearson's correlation and Bland-Altman analyses were performed.

RESULTS

One-hundred and sixteen subjects were enrolled, with obtainable USCOM-1A CI measurements for 99 subjects (55 adults age 50 +/- 20 years and 44 children age 11 +/- 4 years) in the final analysis. Cardiac, gastrointestinal and infectious illnesses were the most common presenting diagnostic categories. The reference standard TTE measurements of CI, SVI, OTD, and VTI in all subjects were 3.08 +/- 1.18 L/min/m(2), 37.10 +/- 10.91 mL/m(2), 1.92 +/- 0.36 cm, and 20.36 +/- 4.53 cm, respectively. Intra-operator reliability of USCOM-1A CI measurements showed a correlation coefficient of r = 0.79, with 11 +/- 22% difference between repeated measures. The bias and limits of agreement of USCOM-1A compared to TTE CI were 0.58 (-1.48 to 2.63) L/min/m(2). The percent difference in CI measurements with USCOM-1A was 31 +/- 28% relative to TTE measurements.

CONCLUSIONS

The USCOM-1A hemodynamic monitoring technology showed poor correlation and agreement to standard transthoracic echocardiography measures of cardiac function. The utility of USCOM-1A in the management of critically ill patients remains to be determined.

Choosing patient-tailored hemodynamic monitoring

This article is one of ten reviews selected from the Yearbook of Intensive Care and Emergency Medicine 2010 (Springer Verlag) and co-published as a series in Critical Care. Other articles in the series can be found online at http://ccforum.com/series/yearbook. Further information about the Yearbook of Intensive Care and Emergency Medicine is available from http://www.springer.com/series/2855.

Searching for the Holy Grail: a review of markers of tissue perfusion in pediatric critical care

Goal-directed therapy has become the key to resuscitating critically ill patients since 2001. However, the ideal marker to guide pediatric resuscitation has remained elusive.The ideal marker is specific, sensitive, easy to use, safe, validated, and cost-effective. Lactate and base deficit are validated prognosticators, but both are affected by confounding conditions and resuscitative efforts. Mixed venous oximetry has been successfully used for guiding therapy but requires a pulmonary artery catheter for measurement. Central venous oximetry, on the other hand, can be more easily measured and is now the standard of care in goal-directed therapy for adult septic shock. Pediatric literature related to central venous oximetry is still in relative infancy, but seems promising. Sublingual capnometry may also prove to be useful, but no pediatric research has been published related to this device. Finally, near-infrared spectroscopy monitoring may be useful in highlighting changes in patient conditions, but its use in goal-directed therapy is limited by the wide interpatient variability. In summary, the search for the ideal marker of tissue perfusion continues, but there is promise on the horizon.

Review article: Non-invasive assessment of cardiac output with portable continuous-wave Doppler ultrasound

Cardiac output is considered an important parameter when assessing the cardiovascular status of a critically ill patient. Both non-invasive (e.g. bioimpedance, echocardiography) and invasive methods (Swan Ganz catheter) have been used to measure cardiac output. The ultrasonic cardiac output monitoring device provides a new method of non-invasively assessing cardiac output in various clinical settings. The ultrasonic cardiac output monitoring device was introduced clinically in 2001, and appears to be a promising adjunct in the assessment of the cardiovascular state in a variety of patient cohorts. In this short review article, we will introduce this new technique, discuss the required skills and compare it with methods already in use. In particular, a critical comparison with the 'gold standard', the invasive measurement of cardiac output with the pulmonary artery catheter, will be given.

A survey of Canadian intensivists' resuscitation practices in early septic shock

Introduction

Recent evidence suggests that early, aggressive resuscitation in patients with septic shock reduces mortality. The objective of this survey was to characterize reported resuscitation practices of Canadian physicians caring for adult critically ill patients with early septic shock.

Methods

A scenario-based self-administered national survey was sent out to Canadian critical care physicians. One hypothetical scenario was developed to obtain information on several aspects of resuscitation in early septic shock, including monitoring and resuscitation end-points, fluid administration, red blood cell transfusion triggers, and use of inotropes. The sampling frame was physician members of Canadian national and provincial critical care societies.

Results

The survey response rate was 232 out of 355 (65.3%). Medicine was the most common primary specialty (60.0%), most respondents had practiced for 6 to 10 years (30.0%), and 82.0% were male. The following monitoring devices/parameters were reported as used/measured 'often' or 'always' by at least 89% of respondents: oxygen saturation (100%), Foley catheters (100%), arterial blood pressure lines (96.6%), telemetry (94.3%), and central venous pressure (89.2%). Continuous monitoring of central venous oxygen saturation was employed 'often' or 'always' by 9.8% of respondents. The two most commonly cited resuscitation end-points were urine output (96.5%) and blood pressure (91.8%). Over half of respondents used normal saline (84.5%), Ringers lactate (52.2%), and pentastarch (51.3%) 'often' or 'always' for early fluid resuscitation. In contrast, 5% and 25% albumin solutions were cited as used 'often' or 'always' by 3.9% and 1.3% of respondents, respectively. Compared with internists, surgeons and anesthesiologists (odds ratio (95% confidence interval): 9.8 (2.9 to 32.7) and 3.8 (1.7 to 8.7), respectively) reported greater use of Ringers lactate. In the setting of a low central venous oxygen saturation, 52.5% of respondents reported use of inotropic support 'often' or 'always'. Only 7.6% of physicians stated they would use a red blood cell transfusion trigger of 100 g/l to optimize oxygen delivery further.

Conclusion

Our survey results suggest that there is substantial practice variation in the resuscitation of adult patients with early septic shock. More randomized trials are needed to determine the optimal approach.

Management of sepsis

Severe sepsis remains a common cause of death in surgical patients. Eradication of the septic source and supportive care has long been the mainstay of treatment. In recent years, however, early goal-directed therapy, tighter glucose control, administration of drotrecogin alfa (activated), and steroid replacement have produced improved morbidity and mortality. In the future, a better understanding of the pathophysiology of sepsis and clinical studies may further improve outcomes from severe sepsis.

Interrater reliability of cardiac output measurements by transcutaneous Doppler ultrasound: implications for noninvasive hemodynamic monitoring in the ED

INTRODUCTION

Hemodynamic monitoring is an important aspect of caring for the critically ill patients boarding in the emergency department (ED). The purpose of this study is to investigate the interrater agreement of noninvasive cardiac output measurements using transcutaneous Doppler ultrasound technique.

METHODS

This is a prospective observational cohort study performed in a 32-bed adult ED of an academic tertiary center with approximately 65000 annual patient visits. Patients were enrolled after verbal consent over a 7-month period. The raters were ED personnel involved in patient care. Paired measurements of cardiac index (CI) and stroke volume index (SVI) were obtained from a transcutaneous Doppler ultrasound cardiac output monitor.

RESULTS

A convenience sample of 107 (50 women and 57 men) patients with a median age of 49 (32, 62) years was enrolled. One hundred two paired measurements were performed in 91 patients in whom adequate Doppler ultrasound signals were obtainable. The raters included 35 emergency medicine attending physicians, 31 emergency medicine residents, 80 medical students, 47 nurses, and 11 emergency medical technicians. Cardiac index range was 0.6 to 5.3 L/min per square meter, and SVI range was 7.7 to 63.0 mL/m(2). The correlation of CI measurements between 2 raters was good (r(2) = 0.87; 95% confidence interval, 0.86-1.00; P < .001). Likewise, SVI measurements between 2 raters also showed acceptable correlation (r(2) = 0.84; 95% confidence interval, 0.81-0.96; P < .001). Interrater reliability was strong for CI (kappa = 0.83 with 92.2% agreement) and SVI measurements (kappa = 0.72 with 88.2% agreement). Most patients had an interrater difference below 10% in CI and SVI measurements.

CONCLUSIONS

Emergency department personnel, regardless of their role in patient care, are able to obtain reliable cardiac output measurements in ED patients over a wide range of CI and SVI. Transcutaneous Doppler ultrasound technique may be an alternative to traditional invasive hemodynamic monitoring of critically ill patients presenting to the ED.