The incidence of major morbidity in critically ill patients managed with pulmonary artery catheters: a meta-analysis

The ultrasound-based cardiac output monitoring is a useful tool to define baseline hemodynamic parameters in healthy permanent residents at high altitude: results of a monocentric pilot study

Previous studies on the cardiac data of healthy permanent residents living in high-altitude regions such as Tibet and the Andes have yielded inconsistent findings and significant disparities. These discrepancies can be mainly attributed to the invasive methods conventionally used for parameter evaluation. However, with the introduction of cutting-edge ultrasound technology, there is now an innovative approach to addressing and reconciling these variations. In this pilot study, we employed an ultrasound-based cardiac output monitoring (USCOM) device to evaluate cardiac output and related hemodynamic variables in a group of 20 healthy high-altitude Andean residents (comprising 10 men and 10 women) aged between 26 and 35 years old. The monocentric study was carried out in La Paz, Bolivia, located between at an altitude of 3,600-4,000 m. A total of 60 hemodynamic measurements were evaluated, accounting for three technical replicates per subject. Our results showed strong intrasubject reproducibility and revealed important differences related to both sex and hemodynamic parameters in highlanders compared to individuals residing at sea level. We conclude that USCOM represents a highly reliable technology for performing hemodynamic measurements in high-altitude residents. Our preliminary findings underscore the need for larger studies, encompassing larger sample sizes, specifically tailored to gender considerations, and extendable to broader highland populations. These findings have special significant implications for the management of hemodynamics in intensive care and postoperative settings, warranting further comprehensive research efforts.

Measurement of hemodynamics immediately after vaginal delivery in healthy pregnant women by electrical cardiometry

Few reports have focused on hemodynamics around delivery in pregnant women because of the difficulty of continuous and noninvasive measurement. Electrical cardiometry allows noninvasive continuous monitoring of hemodynamics and has recently been used in non-pregnant subjects. We compared the use of electrical cardiometry versus transthoracic echocardiography in healthy pregnant women and evaluated hemodynamics immediately after vaginal delivery. In Study 1, electrical cardiometry and transthoracic echocardiography were used to measure cardiac output in 20 pregnant women with threatened premature delivery. A significant correlation was found between the two methods, with electrical cardiometry showing the higher cardiac output. In Study 2, heart rate, stroke volume, and cardiac output were continuously measured in 15 women during vaginal delivery up to 2 h postpartum. Cardiac output increased markedly because of an increased heart rate and stroke volume at the time of newborn delivery. The heart rate then immediately returned to baseline, while cardiac output remained elevated for at least 2 h after delivery because of a sustained high stroke volume. Electrical cardiometry was as readily available as transthoracic echocardiography for evaluating hemodynamics and allowed for continuous measurement during labor. High intrapartum cardiac output was sustained for at least 2 h after vaginal delivery. J. Med. Invest. 66 : 75-80, February, 2019.

Impact of parturition on maternal cardiovascular and neuronal integrity in a high risk cohort - a prospective cohort study

Background

To better understand the profound multisystem changes in maternal physiology triggered by parturition, in particular in the underexplored neuronal system, by deploying a panel of pre- vs post-delivery maternal serum biomarkers, most notably the neuronal cytoskeleton constituent neurofilament light chain (NfL). This promising fluid biomarker is not only increasingly applied to investigate disease progression in numerous brain diseases, particularly in proteopathies, but also in detection of traumatic brain injury or monitoring neuroaxonal injury after ischemic stroke.

Methods

The study was nested within a prospective cohort study of pregnant women at risk of developing preeclampsia at the University Hospital of Basel. Paired ante- and postpartum levels of progesterone, soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF), mid-regional pro-atrial natriuretic peptide (MR-proANP), copeptin (CT-proAVP), and NfL were measured in 56 women with complete clinical data.

Results

Placental delivery significantly decreased all placental markers: progesterone 4.5-fold, PlGF 2.2-fold, and sFlt-1 1.7-fold. Copeptin and MR-proANP increased slightly (1.4- and 1.2-fold, respectively). Unexpectedly, NfL levels (median [interquartile range]) increased significantly post-partum: 49.4 (34.7–77.8) vs 27.7 (16.7–31.4) pg/ml (p < 0.0001). Antepartum NfL was the sole independent predictor of NfL peri-partum change; mode of delivery, duration of labor, clinical characteristics and other biomarkers were all unrelated. Antepartum NfL levels were themselves independently predicted only by maternal age.

Conclusions

Parturition per se increases maternal serum NfL levels, suggesting a possible impact of parturition on maternal neuronal integrity.

Interatrial septal motion as a novel index to predict left atrial pressure

We investigated whether the interatrial septal (IAS) motion of each heartbeat which is observed by transesophageal echocardiography reflects left atrial pressure (LAP) in patients with atrial fibrillation (AF). We studied 100 patients (70 males, age 67 ± 9 years) who underwent catheter ablation for AF. The amplitude of IAS motion was measured using M-mode and averaged for five cardiac cycles. Left and right atrial pressures, the left to right atrial pressure gradient were directly measured during the catheter ablation. In patients with sinus rhythm during measurement, elevated mean LAP, larger maximum left to right atrial pressure gradient, and greater left atrial emptying fraction were associated with IAS motion. The optimal cut-off value of the IAS motion for predicting high LAP (mean LAP > 15 mmHg) was 8.5 mm (sensitivity 100%, specificity 70.1%) in patients with sinus rhythm during pressure measurement. In addition, all patients were divided into 6 groups based on rhythm during measurement and cutoff value of IAS motion. In patients with sinus rhythm during measurement, low IAS motion group had a highest prevalence of elevated LAP compared with high IAS motion group (64 vs. 0%, P < 0.0001). The amplitude of interatrial septal motion during sinus rhythm reflects left atrial pressure in patients with atrial fibrillation. Interatrial septal motion could be a new index to predict elevated left atrial pressure.

Intrapartum obstetric management

Maternal cardiac disease complicates approximately 1-2% of all pregnancies in the United States. Just as during the antepartum period, in the immediate period surrounding delivery, obstetrical patients with cardiac disease (both congenital and acquired) will have specialized needs, tailored to the patient and her specific lesion. While the basic principles of labor and delivery management protocols are relevant to this subgroup of patients, there are certain areas in which adjustments must be made. These include endocarditis prophylaxis, recent anticoagulation, fluid management, and the need for increased maternal cardiac monitoring. Awareness of the challenges of the intrapartum period combined with a multi-disciplinary approach from anesthesia, cardiology, and the obstetrical provider will optimize the patient for a safe delivery.

Clinical utility of central venous saturation for the calculation of cardiac index in cardiac patients

BACKGROUND

Mixed venous saturation (MVS) obtained from the distal pulmonary artery (PA) during Swan-Ganz catheterization is the criterion standard for calculating cardiac output (CO) and cardiac index (CI) with the use of the Fick method. We think that calculating CI with the use of central venous saturation (CVS) instead of PA-MVS is both feasible and accurate. Earlier studies were small, enrolled heterogeneous patient populations, and resulted in inconsistent findings.

METHODS

All patients undergoing right heart catheterization from January 2011 to January 2012 in our catheterization lab with simultaneous measurements of MVS obtained from the distal PA and CVS obtained from the superior vena cava (SVC) or right atrium (RA) were included. Out of the 902 patients enrolled, we excluded patients (n = 50) who had known cardiac shunt or dialysis fistula, had duplicate medical records, or were septic. We calculated the CI with the use of the assumed Fick method using both MVS (criterion standard) and CVS (SVC or RA saturations) in the remaining 852 patients. We measured the correlation and the agreement between the 2 methods with the use of the Pearson correlation coefficient and Bland-Altman analysis.

RESULTS

Totals of 112 patients with simultaneous PA and RA saturation measurements (group I) and 740 patients with simultaneous PA and SVC saturation measurements (group II) were included. We found an excellent linear correlation between SVC and PA saturation (r = 0.928) and between RA and PA saturation (r = 0.95). There was also an excellent correlation between CI calculated with the use of PA saturation and CI calculated with the use of SVC (r = 0.87) or RA (r = 0.93) saturation. The mean bias of CVS-derived CI compared with MVS-derived CI (criterion standard) was -0.1 (95% limits of agreement [LOA] -1 to +0.77) in the SVC group and -0.006 (LOA -0.68 to +0.69) in the RA group. Patients with low CI had stronger correlation and smaller bias between the 2 methods compared with those with normal or high CI. The presence of baseline hypoxemia, valvular heart disease, or acute coronary syndrome had no significant effect on the correlation or the bias between the 2 methods.

CONCLUSIONS

In cardiac patients, CVS can be used as a surrogate to true MVS in the calculation of CI. This method is readily available in patients who have central venous access, and may aid in early goal-directed treatment when cardiogenic shock is suspected.

Web-based survey of current trends in hemodynamic monitoring after congenital heart surgery

Strategies for monitoring patients recovering after congenital heart surgery have evolved considerably as technology continues to progress. Monitoring techniques traditionally centered around the comprehensive physical examination have been replaced by a number of revolutionary technologies developed to objectively evaluate various components of the cardiovascular system. Despite scant evidence that these methodologies actually improve outcomes, some have been embraced by clinicians. We developed an Internet survey designed to describe current practices of clinicians who care for patients after congenital heart surgery. There were 162 respondents to our survey with the majority from the United States. The views of cardiologists, intensivists, those dual trained in both cardiology and critical care medicine, and surgeons are all robustly represented in the results. Serial lactate monitoring was the strategy that was utilized most often by respondents (94%), followed by multisite near-infrared spectrometry (NIRS, 67%). There were 78% who utilized the combination of serial lactate and NIRS monitoring. Serial lactate monitoring was the technique that was thought to best represent cardiovascular well-being after heart surgery (40%). The results of this survey suggest that despite the paucity of evidence that clinical outcomes of patients recovering after congenital heart surgery are improved by any of these monitoring techniques, there is almost universal acceptance to monitor patients with serial lactate monitoring, NIRS monitoring, or a combination of these techniques.

Pulmonary artery catheters for adult patients in intensive care

BACKGROUND

Since pulmonary artery balloon flotation catheterization was first introduced in 1970, by HJ Swan and W Ganz, it has been widely disseminated as a diagnostic tool without rigorous evaluation of its clinical utility and effectiveness in critically ill patients. A pulmonary artery catheter (PAC) is inserted through a central venous access into the right side of the heart and floated into the pulmonary artery. PAC is used to measure stroke volume, cardiac output, mixed venous oxygen saturation and intracardiac pressures with a variety of additional calculated variables to guide diagnosis and treatment. Complications of the procedure are mainly related to line insertion. Relatively uncommon complications include cardiac arrhythmias, pulmonary haemorrhage and infarct, and associated mortality from balloon tip rupture.

OBJECTIVES

To provide an up-to-date assessment of the effectiveness of a PAC on mortality, length of stay (LOS) in intensive care unit (ICU) and hospital and cost of care in adult intensive care patients.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 12); MEDLINE (1954 to January 2012); EMBASE (1980 to January 2012); CINAHL (1982 to January 2012), and reference lists of articles. We contacted researchers in the field. We did a grey literature search for articles published until January 2012.

SELECTION CRITERIA

We included all randomized controlled trials conducted in adults ICUs, comparing management with and without a PAC.

DATA COLLECTION AND ANALYSIS

We screened the titles and abstracts and then the full text reports identified from our electronic search. Two authors (SR and MG) independently reviewed the titles, abstracts and then the full text reports for inclusion. We determined the final list of included studies by discussion among the group members (SR, ND, MG, AK and SC) with consensus agreement. We included all the studies that were in the original review. We assessed seven domains of potential risk of bias for the included studies. We examined the clinical, methodological and statistical heterogeneity and used random-effects model for meta-analysis. We calculated risk ratio for mortality across studies and mean days for LOS.

MAIN RESULTS

We included 13 studies (5686 patients). We judged blinding of participants and personnel and blinding of outcome assessment to be at high risk in about 50% of the included studies and at low risk in 25% to 30% of the studies. Regardless of the high risk of performance bias these studies were included based on the low weight the studies had in the meta-analysis. We rated 75% of the studies as low risk for selection, attrition and reporting bias. All 13 studies reported some type of hospital mortality (28-day, 30-day, 60-day or ICU mortality). We considered studies of high-risk surgery patients (eight studies) and general intensive care patients (five studies) separately as subgroups for meta-analysis. The pooled risk ratio (RR) for mortality for the studies of general intensive care patients was 1.02 (95% confidence interval (CI) 0.96 to 1.09) and for the studies of high-risk surgery patients the RR was 0.98 (95% CI 0.74 to 1.29). Of the eight studies of high-risk surgery patients, five evaluated the effectiveness of pre-operative optimization but there was no difference in mortality when these studies were examined separately. PAC did not affect general ICU LOS (reported by four studies) or hospital LOS (reported by nine studies). Four studies, conducted in the United States (US), reported costs based on hospital charges billed, which on average were higher in the PAC groups. Two of these studies qualified for analysis and did not show a statistically significant hospital cost difference (mean difference USD 900, 95% CI -2620 to 4420, P = 0.62).

AUTHORS' CONCLUSIONS

PAC is a diagnostic and haemodynamic monitoring tool but not a therapeutic intervention. Our review concluded that use of a PAC did not alter the mortality, general ICU or hospital LOS, or cost for adult patients in intensive care. The quality of evidence was high for mortality and LOS but low for cost analysis. Efficacy studies are needed to determine if there are optimal PAC-guided management protocols, which when applied to specific patient groups in ICUs could result in benefits such as shock reversal, improved organ function and less vasopressor use. Newer, less-invasive haemodynamic monitoring tools need to be validated against PAC prior to clinical use in critically ill patients.

Hemodynamic monitoring in the intensive care unit

Patients in the intensive care unit are often critically ill with inadequate tissue perfusion and oxygenation. This inadequate delivery of substrates at the cellular level is a common definition of shock. Hemodynamic monitoring is the observation of cardiovascular physiology. The purpose of hemodynamic monitoring is to identify abnormal physiology and intervene before complications, including organ failure and death, occur. The most common types of invasive hemodynamic monitors are central venous catheters, pulmonary artery catheters, and arterial pulse-wave analysis. Ultrasonography is a noninvasive alternative being used in intensive care units for hemodynamic measurements and assessments.

The pulmonary artery catheter

The pulmonary artery catheter (PAC) has been widely used for monitoring of critically ill patients over the years, but with advances in less invasive monitoring techniques, notably echocardiography, there are fewer indications for PAC insertion. Nevertheless, the PAC provides simultaneous monitoring of pulmonary artery pressures, cardiac filling, cardiac output and mixed venous oxygen saturation, and still has an important role in complex cases. Adequate and continued training are required to ensure that PAC-derived data are correctly interpreted and applied.

The effect of weight-based volume loading on the inferior vena cava in fasting subjects: a prospective randomized double-blinded trial

OBJECTIVES

Inferior vena cava ultrasound (IVC-US) assessment has been proposed as a noninvasive method of assessing volume status. Current literature is divided on its ability to do so. The primary objective was to compare IVC-US changes in healthy fasting subjects randomized to either 10 or 30 mL/kg of intravenous (IV) fluid administration versus a control group that received only 2 mL/kg.

METHODS

This was a prospective randomized double-blinded trial set in emergency department (ED) clinical care rooms. Volunteer subjects with no history of cardiac disease or hypertension fasted for 12 hours. Subjects were randomly assigned to receive IV 0.9% saline bolus of 2 (control group), 10, or 30 mL/kg over 30 minutes. IVC-US was performed before and 15 minutes after each fluid bolus.

RESULTS

Forty-two fasting subjects were enrolled. Analysis of variance (ANOVA) comparison showed that IVC-US was unable to detect any significant difference between the control group and those given either 10 or 30 mL/kg fluid, whether using maximum or minimum IVC diameter or caval index (IVC-CI). The groups receiving 10 and 30 mL/kg each had a statistically significant change in IVC-CI; however, the 30 mL/kg group had no significant change in either of the mean IVC diameters.

CONCLUSIONS

Overall, there were statistically significant differences in mean IVC-US measurements before and after fluid loading, but not between groups. Fasting asymptomatic subjects had a wide intersubject variation in both baseline IVC-US measurements and fluid-related changes. The degree of IVC-US change in association with graded acute volume loading was not predictably proportional between our subjects.

Systematic review of methods used in meta-analyses where a primary outcome is an adverse or unintended event

BACKGROUND

Adverse consequences of medical interventions are a source of concern, but clinical trials may lack power to detect elevated rates of such events, while observational studies have inherent limitations. Meta-analysis allows the combination of individual studies, which can increase power and provide stronger evidence relating to adverse events. However, meta-analysis of adverse events has associated methodological challenges. The aim of this study was to systematically identify and review the methodology used in meta-analyses where a primary outcome is an adverse or unintended event, following a therapeutic intervention.

METHODS

Using a collection of reviews identified previously, 166 references including a meta-analysis were selected for review. At least one of the primary outcomes in each review was an adverse or unintended event. The nature of the intervention, source of funding, number of individual meta-analyses performed, number of primary studies included in the review, and use of meta-analytic methods were all recorded. Specific areas of interest relating to the methods used included the choice of outcome metric, methods of dealing with sparse events, heterogeneity, publication bias and use of individual patient data.

RESULTS

The 166 included reviews were published between 1994 and 2006. Interventions included drugs and surgery among other interventions. Many of the references being reviewed included multiple meta-analyses with 44.6% (74/166) including more than ten. Randomised trials only were included in 42.2% of meta-analyses (70/166), observational studies only in 33.7% (56/166) and a mix of observational studies and trials in 15.7% (26/166). Sparse data, in the form of zero events in one or both arms where the outcome was a count of events, was found in 64 reviews of two-arm studies, of which 41 (64.1%) had zero events in both arms.

CONCLUSIONS

Meta-analyses of adverse events data are common and useful in terms of increasing the power to detect an association with an intervention, especially when the events are infrequent. However, with regard to existing meta-analyses, a wide variety of different methods have been employed, often with no evident rationale for using a particular approach. More specifically, the approach to dealing with zero events varies, and guidelines on this issue would be desirable.

Applications of minimally invasive cardiac output monitors

Because of the increasing age of the population, critical care and emergency medicine physicians have seen an increased number of critically ill patients over the last decade. Moreover, the trend of hospital closures in the United States t imposes a burden of increased efficiency. Hence, the identification of devices that facilitate accurate but rapid assessments of hemodynamic parameters without the added burden of invasiveness becomes tantamount. The purpose of this review is to understand the applications and limitations of these new technologies.

Pulmonary hypertension in critical care

PURPOSE OF REVIEW

To review the contemporary management of patients with pulmonary hypertension in critical care.

RECENT FINDINGS

The normal mean pulmonary artery pressure (mPAP) at rest is 14±3  mmHg and pulmonary hypertension is considered when mPAP is greater than or equal to 25  mmHg at rest. The classification of pulmonary hypertension has been redefined recently and updated in 2009 and could help to guide the management of patients with pulmonary hypertension in critical care. The management of pulmonary hypertension in ICU is based on expert opinion. Among the diagnostic and monitoring tools available, echocardiography provides useful information noninvasively, although pulmonary artery catheter must be used in case of complicated situations. Calcium sensitizers, a new class of inotrope, have inotropic effects and induce dilatation of the pulmonary, systemic, and coronary vasculature and thus could be useful in case of right ventricular failure (RVF), particularly in patients with acute respiratory distress syndrome (ARDS). By increasing the pulmonary vasodilator response to inhaled nitric oxide and preventing the rebound pulmonary vasoconstriction which occurs following cessation of nitric oxide breathing, selective type 5 isoform of phosphodiesterase inhibitors could be useful in critically ill patients.

SUMMARY

This article reviews recent and key findings on the management of pulmonary hypertension in critically ill patients.

Cardiac output monitoring devices: an analytic review

To evaluate cardiac output (CO), both invasive and semi-invasive monitors are used in critical care medicine. The pulmonary artery catheter is an invasive tool to assess CO with the major criticism that the level of its invasiveness is not supported by an improvement in patients' outcomes. The interest in a lesser invasive techniques is high. Therefore, alternative techniques have been developed recently, and are used frequently in critical care medicine. Cardiac output can be monitored continuously by different devices that analyze the stroke volume and CO. The purpose of this review is to understand these new technologies and their applications and limitations.

Low central venous oxygen saturation is associated with increased mortality in critically ill dogs

OBJECTIVES

To investigate relationships between central venous oxygen saturation (ScvO(2)) and survival to hospital discharge in dogs. Central venous oxygen saturation is an accessible measure of the balance between systemic oxygen delivery and consumption.

METHODS

Prospective observational cohort study, enrolling 126 client-owned dogs with central venous catheters. Central venous oxygen saturation was measured over the 24 hours following intensive care unit admission. Poor outcome was defined as death or euthanasia performed for moribund status. Regression analysis identified independent predictors of non-survival and physiologic parameters associated with central venous oxygen saturation. Area under the receiver operator curve analysis identified a cut-off point of central venous oxygen saturation, below which central venous oxygen saturation decrease was associated with increased mortality risk.

RESULTS

Mortality risk was 30·9%. Low central venous oxygen saturation was associated with poor outcome (P<0·05). Area under the receiver operator curve analysis selected a central venous oxygen saturation of 68% as the point below which a fall in central venous oxygen saturation was associated with increased mortality risk. For each 10% drop in central venous oxygen saturation below 68%, odds of non-survival increased by 2·66 times (P=0·0002, 95% confidence interval of odds ratio=1·45 to 4·85). Central venous oxygen saturation was equivalent to lactate in predicting non-survival. Predictors of central venous oxygen saturation (packed cell volume, mean arterial blood pressure, fever, % arterial haemoglobin saturation as measured by pulse oximeter) were consistent with hypothesised physiologic mechanisms.

CLINICAL SIGNIFICANCE

Central venous oxygen saturation was a strong mortality predictor. Further work is needed to determine if therapy targeting central venous oxygen saturation can reduce mortality in canine intensive care unit patients.

Early non-invasive cardiac output monitoring in hemodynamically unstable intensive care patients: a multi-center randomized controlled trial

INTRODUCTION

Acute hemodynamic instability increases morbidity and mortality. We investigated whether early non-invasive cardiac output monitoring enhances hemodynamic stabilization and improves outcome.

METHODS

A multicenter, randomized controlled trial was conducted in three European university hospital intensive care units in 2006 and 2007. A total of 388 hemodynamically unstable patients identified during their first six hours in the intensive care unit (ICU) were randomized to receive either non-invasive cardiac output monitoring for 24 hrs (minimally invasive cardiac output/MICO group; n = 201) or usual care (control group; n = 187). The main outcome measure was the proportion of patients achieving hemodynamic stability within six hours of starting the study.

RESULTS

The number of hemodynamic instability criteria at baseline (MICO group mean 2.0 (SD 1.0), control group 1.8 (1.0); P = .06) and severity of illness (SAPS II score; MICO group 48 (18), control group 48 (15); P = .86)) were similar. At 6 hrs, 45 patients (22%) in the MICO group and 52 patients (28%) in the control group were hemodynamically stable (mean difference 5%; 95% confidence interval of the difference -3 to 14%; P = .24). Hemodynamic support with fluids and vasoactive drugs, and pulmonary artery catheter use (MICO group: 19%, control group: 26%; P = .11) were similar in the two groups. The median length of ICU stay was 2.0 (interquartile range 1.2 to 4.6) days in the MICO group and 2.5 (1.1 to 5.0) days in the control group (P = .38). The hospital mortality was 26% in the MICO group and 21% in the control group (P = .34).

CONCLUSIONS

Minimally-invasive cardiac output monitoring added to usual care does not facilitate early hemodynamic stabilization in the ICU, nor does it alter the hemodynamic support or outcome. Our results emphasize the need to evaluate technologies used to measure stroke volume and cardiac output--especially their impact on the process of care--before any large-scale outcome studies are attempted.

TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov (Clinical Trials identifier NCT00354211).

Current concepts in resuscitation

Early recognition and differentiation of shock, as well as goal-directed resuscitation, are fundamental principles in the care of the critically ill or injured patient. Substantial progress has been made over the last decade in the understanding of both shock and resuscitation. Specific areas of advancement, particularly pertaining to hemorrhagic shock, include a heightened appreciation of dynamic measurements of preload responsiveness (e.g., respiratory-induced pulse pressure and venous diameter variability), an improved awareness of the detrimental effects of blood product transfusion, and better recognition of the complications of overzealous volume expansion. However, several areas of controversy remain regarding the optimal resuscitation strategy. These include the optimal targets for perfusion pressure and oxygen delivery, endpoints of resuscitation, resuscitative fluid, and transfusion strategies for packed red blood cells and blood products. This article reviews the diagnosis and differentiation of shock, measurements of tissue perfusion, current evidence regarding various resuscitative techniques, and complications of resuscitation.

Access technique and its problems in parenteral nutrition - Guidelines on Parenteral Nutrition, Chapter 9

Catheter type, access technique, and the catheter position should be selected considering to the anticipated duration of PN aiming at the lowest complication risks (infectious and non-infectious). Long-term (>7-10 days) parenteral nutrition (PN) requires central venous access whereas for PN <3 weeks percutaneously inserted catheters and for PN >3 weeks subcutaneous tunnelled catheters or port systems are appropriate. CVC (central venous catheter) should be flushed with isotonic NaCl solution before and after PN application and during CVC occlusions. Strict indications are required for central venous access placement and the catheter should be removed as soon as possible if not required any more. Blood samples should not to be taken from the CVC. If catheter infection is suspected, peripheral blood-culture samples and culture samples from each catheter lumen should be taken simultaneously. Removal of the CVC should be carried out immediately if there are pronounced signs of local infection at the insertion site and/or clinical suspicion of catheter-induced sepsis. In case PN is indicated for a short period (max. 7-10 days), a peripheral venous access can be used if no hyperosmolar solutions (>800 mosm/L) or solutions with a high titration acidity or alkalinity are used. A peripheral venous catheter (PVC) can remain in situ for as long as it is clinically required unless there are signs of inflammation at the insertion site.

[Preliminary clinical experience with PiCCO system in children with shock]

PURPOSE

To evaluate the PiCCO hemodynamics monitor in terms of clinical usefulness in children with shock.

METHODS

Prospective multicenter analytical study in children aged from one month to 18 years with shock admitted to five pediatric intensive care units. Measurements were made before and after three interventions: a) volume load; b) increases in vasoactive drugs; c) dosage changes of drugs that could lessen vascular resistance. Recorded parameters included thermodilution data, along with the usual hemodynamic parameters.

RESULTS

A total of 120 measurements were performed on 35 patients: mean age 36 (2.6-156) months, mean weight 15 (5.8-72) kg. Shock etiology was septic in 37% of cases, cardiogenic in 26%, hypovolemic in 20% and neurogenic in 17%. No procedure related complication was noticed. Twenty-two volume challenges in 17 patients were registered. Volume load induced a significant intrathoracic blood volume index (ITBI) increase from 501(235-763) to 584 (418-810) ml/m(2), cardiac index (CI) 4.04 (2.58-6.25) to 4.48 (2.86-8.71) lmin-1m(2), and mean blood pressure from 74 (53-99) to 87 (59-112) mmHg. CI changes correlated with ITBI increase (r = 0.678, p = 0.001). 13 interventions to increase vasomotor tone were associated with an increase in contractility of 18% in systemic vascular resistance index (SVRI).

CONCLUSIONS

Hemodynamic monitoring with the PiCCO system is feasible and seems safe in children with shock. PiCCO derived parameters could add clinically important information to assess preload state and its modifications with therapy.

Continuous cardiac index monitoring: A prospective observational study of agreement between a pulmonary artery catheter and a calibrated minimally invasive technique

INTRODUCTION

Continuous cardiac index (CCI) monitoring can provide information to assist in hemodynamic support. However, pulmonary artery catheters (PAC) pose logistic challenges in acute care settings. We hypothesized that CCI measured with a calibrated minimally invasive technique (LiDCO/PulseCO, UK) would have good agreement with the PAC.

METHODS

We performed a prospective observational study in post-operative cardiac surgery patients. All patients had a PAC with CCI monitoring capability. We connected the LiDCO apparatus to a radial artery line and performed a one-time calibration with a lithium dilution indicator. In order to test the least invasive method possible, we used a peripheral intravenous (IV) line for indicator delivery rather than the conventional central line technique. We recorded paired PAC/LiDCO-PulseCO CCI measurements every minute for 3h. We blinded investigators and clinicians to minimally invasive data with an opaque shield over the monitor. We assessed agreement with Bland-Altman analysis.

RESULTS

We obtained 1485 paired measurements in 8 subjects. The mean CI was 2.9L/min/m(2). By Bland-Altman plot, PAC and LiDCO measurements showed minimal bias (-0.01), but the 95% limits of agreement (+/-2SD) of+/-1.3L/min/m(2) were relatively wide with respect to the mean.

CONCLUSIONS

This calibrated minimally invasive (i.e. radial arterial line and peripheral IV) technique demonstrated low bias compared with CCI measured by PAC. However, the relatively wide confidence limits indicate that differences in the two measurements could still be clinically significant.

Comparison of pulmonary artery and aortic transpulmonary thermodilution for monitoring of cardiac output in patients with severe heart failure: validation of a novel method

OBJECTIVE

Hemodynamic monitoring with the pulmonary artery catheter is frequently used in the management of severe heart failure. For measurement of cardiac output (CO), transpulmonary thermodilution (TPTD) has recently been adopted into clinical practice as an alternative to pulmonary artery thermodilution. However, no data have been published on the comparability of the two methods for patients with severely reduced left ventricular function. Our objective was to evaluate the correlation between these two methods of CO determination in patients with severe left ventricular dysfunction.

DESIGN

Prospective observational clinical study.

SETTING

Cardiological intermediate care unit and medical intensive care unit of a university hospital.

PATIENTS

Twenty-nine patients with left ventricular ejection fraction <35% and symptoms of heart failure (New York Heart Association class III-IV).

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

The two methods of intermittent CO measurement were compared by simultaneously recording the results of pulmonary artery thermodilution and TPTD after injection of a cold saline bolus. Measurements were performed when clinically necessary. A total of 325 data pairs were analyzed. Mean CO of both methods was 4.4 L/min with a bias of 0.45 L/min (2 SD 1.20 L/min), resulting in a percentage error of 27.3%.

CONCLUSION

In patients with severely impaired left ventricular function, measurement of CO by TPTD provides valid results.

Noninvasive cardiac output determination: broadening the applicability of hemodynamic monitoring

Although cardiac output (CO) monitoring is usually only used in intensive care units (ICUs) and operating rooms, there is increasing evidence that CO should be determined and optimized as early as possible, even before admission to the ICU, in the care of hemodynamically compromised patients. A variety of different minimally or noninvasive CO determination techniques have been developed, but not all of them are suitable for early hemodynamic monitoring outside the ICU. In this review, the different available methods for CO monitoring are presented and their potential for early hemodynamic assessment is discussed.

Transesophageal echocardiography and noncardiac surgery

The use of transesophageal echocardiography (TEE) for monitoring during cardiac and noncardiac surgery has increased exponentially over the past few decades. TEE has evolved from a diagnostic tool to a monitoring device and a procedural adjunct. The close proximity of the TEE transducer to the heart generates high-quality images of the intracardiac structures and their spatial orientation. The use of TEE in noncardiac and critical care settings is not well studied, and the evidence of the benefits of its use in these settings is lacking. Despite the widespread availability of TEE equipment in US hospitals, less than 30% of anesthesiologists are formally trained in the use of perioperative TEE. In this review, the safety and indications of TEE are reviewed and detailed analysis of the best available evidence in this regard is presented. Landmark trials evaluating the use of TEE and its therapeutic impact in noncardiac surgical setting are critically reviewed. This article details recommendations to familiarize anesthesiologists with TEE technology to exploit it to its fullest potential to achieve better patient monitoring standards and eventually improve outcome. Training of greater numbers of anesthesiologists in TEE is needed to increase awareness of the indications and contraindications. Until relatively inexpensive TEE equipment is available, the initial cost of equipment acquisition remains a significant prohibitive factor limiting its widespread use.

Traumatic brain injury: an integrated clinical case presentation and literature review part II: the continuum of care

The following paper continues the presentation of a case scenario outlining the assessment, interventions and outcome of a person who sustained multiple trauma with a focus on traumatic brain injury (TBI). Part I explored assessment and initial management of the patient from pre-hospital care through to the emergency department and operating theatre. Part II describes the intensive care period as an integral component of the continuum of care. Key issues in the case are presented sequentially with relevant theory integrated and applied to the clinical case throughout the discussion with a focus on the complex physiological, psychological, and spiritual needs of the patient and their family.

Comparison of complications and procedural activities of pulmonary artery catheter removal by critical care nurses versus medical doctors

BACKGROUND

None of the nursing studies on PA catheter removal pointed out any differences in complications after removal and procedural activities for removal of PA catheter by CCNs vs MDs in Turkey.

AIMS

This quasi-experimental study was conducted to determine the occurrence and type of complications and to indicate the differences between CCNs and medical doctors' (MDs) activities for removal of PA catheter.

METHODS

Totally, 60 critical care unit patients were scheduled as a sample, and they were assigned randomly to the CCN (n = 30) or to the MD (n = 30) groups. For the comparison purposes of the different activities and complications of PA catheter removal procedure between the two groups, 'Instruction Form' was followed step by step. The differences in the prevalence of variables were tested using Student's t statistics. For categorical data, Fisher's exact test was used. Significance was declared by P value of <0.05.

RESULTS

Preprocedural activities like patient positioning (P < 0.001) and instructing the patient for breathing (P = 0.001) demonstrated statistically significant differences between the two groups. The PA catheters were removed properly in both groups (P > 0.05). The majority of postprocedural activities were completed successfully. The complications of the catheter removal were documented more carefully by nurses compared with doctors (P < 0.01). Additionally, singular premature ventricular complexes were observed on electrocardiogram in both groups (P > 0.05).

CONCLUSION

Instructing CCNs to remove a PA catheter has been highlighted in keeping the number of complications associated with removal procedure of PA catheter.

Hemodynamic monitoring in acute heart failure

Hemodynamic monitoring has moved in the last few years from being the holy grail of evaluating patients with acute heart failure to being all but extinct. Recent studies have not demonstrated any sustained benefits from right heart catheterization, and some studies have even suggested harm due to adverse events related to this invasive procedure. It is possible that this lack of efficacy is related to multiple inherent deficiencies in the design of these studies, including the inclusion of patients with chronic heart failure or mild acute heart failure, use of the reduction in pulmonary artery occlusion pressure as the main hemodynamic target for intervention, choice of treatment algorithms, and selection of ambitious long-term efficacy and safety end points. This review discusses the role of hemodynamic monitoring in patients with acute heart failure. We suggest that right heart catheterization should be reserved for patients with acute heart failure and impending respiratory or circulatory failure especially in the presence of a diagnostic or therapeutic dilemma or when encountering acute heart failure or hemodynamic lability refractory to conventional therapy. Therapeutic algorithms emphasizing modern variables for cardiovascular performance and using safer and more efficacious individualized therapies and possibly noninvasive measurement of certain hemodynamic variables may enhance the likelihood of a beneficial effect for hemodynamic guided therapy.

Invasive hemodynamic monitoring the aftermath of the ESCAPE trial

The Swan-Ganz catheter was developed 35 to 40 years ago for intensive and cardiac care units to allow bedside placement and continuous monitoring and recording of right-sided heart, pulmonary artery, and wedge pressures and reasonably accurate determinations of cardiac output. Considerations for the clinical application of this balloon-tip, flow-directed, multilumen, thermodilution pulmonary artery catheter in the post-ESCAPE era are presented.

Which general intensive care unit patients can benefit from placement of the pulmonary artery catheter?

From the report by Connors and coworkers in 1996 until now, much effort has been directed at demonstrating the safety and/or effectiveness of strategies based on pulmonary artery catheter (PAC) data. Although studies have failed to demonstrate a clear benefit of PAC use, neither have any corroborated the initial report of PAC-induced mortality. With this in mind, it is important to clarify the indications for PAC, taking into account the development of new technologies to measure cardiac output and stroke volume. The present review focuses on safety and effectiveness data, with a special focus on reasonable indications for PAC use in the intensive care unit. The PAC has evolved since its initial presentation, and it now offers numerous parameters in addition to cardiac output and pressure measurement, such as mixed oxygen saturation and right ventricular ejection fraction. Because many techniques may be used to measure cardiac output, the indications for PAC use have become founded on other parameters that are useful in more specific situations, essentially involving the right circulation.

Radial Artery Pulse Pressure Variation Correlates With Brachial Artery Peak Velocity Variation in Ventilated Subjects When Measured by Internal Medicine Residents Using Hand-Carried Ultrasound Devices

BACKGROUND

Rapid prediction of the effect of volume expansion is crucial in unstable patients receiving mechanical ventilation. Both radial artery pulse pressure variation (DeltaPP) and change of aortic blood flow peak velocity are accurate predictors but may be impractical point-of-care tools.

PURPOSES

We sought to determine whether respiratory changes in the brachial artery blood flow velocity (DeltaVpeak-BA) as measured by internal medicine residents using a hand-carried ultrasound (HCU) device could provide an accurate corollary to DeltaPP in patients receiving mechanical ventilation.

METHODS

Thirty patients passively receiving volume-control ventilation with preexisting radial artery catheters were enrolled. The brachial artery Doppler signal was recorded and analyzed by blinded internal medicine residents using a HCU device. Simultaneous radial artery pulse wave and central venous pressure recordings (when available) were analyzed by a blinded critical care physician.

RESULTS

A Doppler signal was obtained in all 30 subjects. The DeltaVpeak-BA correlated well with DeltaPP (r = 0.84) with excellent agreement (weighted kappa, 0.82) and limited intraobserver variability (2.8 +/- 2.8%) [mean +/- SD]. A DeltaVpeak-BA cutoff of 16% was highly predictive of DeltaPP > or = 13% (sensitivity, 91%; specificity, 95%). A poor correlation existed between the CVP and both DeltaVpeak-BA (r = - 0.21) and DeltaPP (r = - 0.16).

CONCLUSIONS

The HCU Doppler assessment of the DeltaVpeak-BA as performed by internal medicine residents is a rapid, noninvasive bedside correlate to DeltaPP, and a DeltaVpeak-BA cutoff of 16% may prove useful as a point-of-care tool for the prediction of volume responsiveness in patients receiving mechanical ventilation.

Current practice of hemodynamic monitoring and vasopressor and inotropic therapy in post-operative cardiac surgery patients in Germany: results from a postal survey

BACKGROUND

In Germany, more than 100,000 patients are monitored and treated in 80 intensive care units (ICUs) following cardiac surgery each year. The controversies concerning the different methods of hemodynamic monitoring and the appropriate agents for volume therapy and inotropic support are well known. However, little is known about how monitoring and treatment are currently performed.

METHODS

A questionnaire with 39 questions was sent to the leading physicians of 80 ICUs in Germany, treating patients after cardiac surgery. The questions to be answered covered the current practice of hemodynamic monitoring, volume replacement, inotropic/vasopressor support and transfusions in patients after cardiac surgery.

RESULTS

Sixty-nine per cent of the questionnaires were completed and returned. All ICUs used basic monitoring as recommended by the societies. The use of advanced hemodynamic monitoring included the pulmonary artery catheter (58.2%), transesophageal echocardiography (38.1%) and transpulmonary dilution techniques (13%). Crystalloids (21.2%) and colloids (73%) were used for volume replacement. Epinephrine (41.8%) and dobutamine (30.9%) were the first-choice inotropic drugs for the treatment of low cardiac output syndrome, followed by phosphodiesterase inhibitors (14.5%). Second-choice drugs for the treatment of low cardiac output syndrome were enoximone (29%), milrinone (25%) and dobutamine (25%). A written transfusion protocol and a transfusion threshold for red blood cells existed in 59% and 79% of ICUs, respectively.

CONCLUSION

Hemodynamic monitoring and the variability in clinical practice with regard to volume replacement, transfusion triggers and the use of vasopressors/inotropes in cardiac surgery patients tend to follow the results of traditional experience rather than current scientific knowledge. Guidelines are therefore necessary to help to improve the standards of intensive care after cardiac surgery and thus the outcome of patients.

The pulmonary artery catheter: the tool versus treatments based on the tool

The pulmonary artery catheter (PAC) is a powerful tool that has been used extensively in the assessment and monitoring of cardiovascular physiology. Gross misinterpretation of data gathered by the PAC is common, and its routine use without any specific interventions has not been shown to influence outcome. However, there currently is no evidence from randomized, controlled trials that any diagnostic or monitoring tool used in intensive care patients improves outcome. Studies evaluating the use of the PAC have included numerous potential confounding factors, and should be interpreted with caution. The information obtained with the PAC should be used to find better treatment strategies, and these strategies, instead of the tool itself, should be tested in clinical trials.

Critical care issues in the early management of severe trauma

Violent trauma and road traffic injuries kill more than 2.5 million people in the world every year, for a combined mortality of 48 deaths per 100,000 population per year. Most trauma deaths occur at the scene or in the first hour after trauma, with a proportion from 34% to 50% occurring in hospitals. Preventability of trauma deaths has been reported as high as 76% and as low as 1% in mature trauma systems. Critical care errors may occur in a half of hospital trauma deaths, in most of the cases contributing to the death. The most common critical care errors are related to airway and respiratory management, fluid resuscitation, neurotrauma diagnosis and support, and delayed diagnosis of critical lesions. A systematic approach to the trauma patient in the critical care unit would avoid errors and preventable deaths.

Rupture de l'artère pulmonaire par cathéter de Swan-Ganz au cours de la chirurgie cardiaque : conduite à tenir et stratégie

Pulmonary artery catheterization is almost uniformly used nowadays in cardiac surgery. Although rare, rupture of the pulmonary artery following catheterization is highly lethal. This review examines ways of avoiding its occurrence and means of improving outcomes in case of rupture.

Pulmonary artery catheters for adult patients in intensive care

BACKGROUND

Pulmonary artery catheterization was adopted about 30 years ago and widely disseminated without rigorous evaluation as to whether it benefited critically ill patients. The technique is used to measure cardiac output and pressures in the pulmonary circulation to guide diagnosis and treatment. Clinicians believe these data can improve patients' outcomes, even in the absence of consensus about the specific interpretation of the data.

OBJECTIVES

To assess the effect of pulmonary artery catheterization on mortality and cost of care in adult intensive care patients.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2006); MEDLINE (all records to April 2006); EMBASE (all records to April 2006); CINAHL (all records to April 2006) and reference lists of articles. We contacted manufacturers and researchers in the field.

SELECTION CRITERIA

We included all randomized controlled trials in adults, comparing management with and without a pulmonary artery catheter (PAC).

DATA COLLECTION AND ANALYSIS

We screened the titles and abstracts of the electronic search results and obtained the full text of studies of possible relevance for independent review. We determined the final results of the literature search by consensus between the authors. We did not contact study authors for additional information.

MAIN RESULTS

We identified 12 studies. Mortality was reported as hospital, 28-day, 30-day, or intensive care unit. We considered studies of high-risk surgery patients (eight studies) and general intensive care patients (four studies) separately for the meta-analysis. The pooled odds ratio for the studies of general intensive care patients was 1.05 (95% confidence interval (CI) 0.87 to 1.26) and for the studies of high-risk surgery patients 0.99 (95% CI 0.73 to 1.24). Of the eight studies of high-risk surgery patients, five evaluated the effectiveness of pre-operative optimization but there was no difference in mortality when these studies were examined separately. Pulmonary artery catheterization did not affect intensive care unit (reported by 10 studies) or hospital (reported by nine studies) length of stay. Four studies, conducted in the United States, measured costs based on hospital charges billed to patients, which on average were higher in the PAC groups.

AUTHORS' CONCLUSIONS

To date, there have been two multi-centre trials of the effectiveness of PACs for managing critically ill patients admitted to intensive care, although only one was adequately powered. Efficacy studies are needed to determine optimal management protocols and patient groups who could benefit from management with a PAC.

Esophageal Doppler monitoring for hemodynamic assessment

This article reviews the importance of hemodynamic monitoring in adding to the clinical assessment of critically ill patients. The esophageal Doppler monitor (EDM) provides a less invasive way of obtaining hemodynamic information quickly and safely at the bedside. The concepts of Doppler signal acquisition and important nursing considerations are reviewed. Case studies are provided to understand how data from the EDM can impact patient care decisions at the bedside.

Use of the pulmonary artery catheter is not associated with worse outcome in the ICU

STUDY OBJECTIVES

In critically ill patients, the impact of pulmonary artery catheter (PAC) use on outcome is debatable. We investigated the epidemiology of PAC use in European ICUs and its relation to outcome.

DESIGN

International cohort, observational study.

SETTING

One hundred ninety-eight European ICUs participating in the Sepsis Occurrence in Acutely Ill Patients Study.

PATIENTS

All 3,147 adult patients admitted to one of the participating ICUs between May 1, 2002, and May 15, 2002.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Patients were classified according to whether or not they had a PAC at any time during their ICU stay, and were followed up until death, hospital discharge, or for 60 days. Propensity score case matching was performed, and matched pairs were examined for baseline characteristics and outcome. Of 3,147 patients, 481 patients (15.3%) had a PAC. Patients with a PAC were older, had a higher incidence of heart failure, a lower incidence of cancer, and were more commonly surgical admissions. Fluid balance was comparable between the two groups. ICU and hospital mortality rates were higher in patients with a PAC (28.1% vs 16.8% and 32.5% vs 22.5%, respectively; p < 0.001). However, PAC use was not an independent risk factor for 60-day mortality in multivariate analysis, and in 453 propensity-matched pairs ICU and hospital mortality rates were comparable between groups (26.7% vs 26.3% and 31.4% vs 32.8%, p = not significant). Survival to 60 days was similar between the two matched groups (log rank = 0.02; p = 0.894).

CONCLUSIONS

This observational study suggests that PAC use is not associated with increased mortality in this heterogeneous population.

Echo-Doppler and clinical evaluations to define hemodynamic profile in patients with chronic heart failure: accuracy and influence on therapeutic management

BACKGROUND

Correct classification of chronic heart failure (CHF) patients by dual evidence of congestion and adequate perfusion is the primary clinical focus for management.

OBJECTIVES

To evaluate the accuracy of echo-Doppler compared with clinical evaluation in determining the hemodynamic profile of patients with CHF; and to compare therapeutic changes based on hemodynamic or echo-Doppler findings.

METHODS

Three hundred and sixty-six consecutive CHF patients (ejection fraction 25+/-7%) in sinus rhythm, undergoing evaluation for cardiac transplantation, underwent physical examination prior to right heart catheterization and echo-Doppler studies. Subsequently, patients were randomized to therapeutic optimization using either right heart catheterization or echo-Doppler data. The end-points were: identification of low cardiac output (cardiac index <2.2 l/min/m(2)); high pulmonary wedge pressure (PWP >18 mm Hg); high right atrial pressure (RAP >5 mm Hg) and analysis of therapeutic changes made in response to the right heart catheterization and echo-Doppler studies.

RESULTS

Echo-Doppler showed better accuracy in estimating abnormal hemodynamic indices than clinical variables (cardiac index <2.2 l/min/m(2): echo positive predictive accuracy (PPA) 98% vs. clinical PPA 52% p<0.00001; PWP >18 mm Hg: echo PPA 85% vs. clinical PPA 76% p=0.0011; RAP >5 mm Hg: echo PPA 82% vs. clinical PPA 57% p<0.00001). When applied to individual patients, the echo-Doppler assessment was more accurate than clinical evaluation in defining the different hemodynamic profiles: wet/cold (89% vs. 13%, p<0.0001); wet/warm (73% vs. 30%, p<0.0001); dry/cold (68% vs. 12%, p<0.0001); dry/warm (88% vs. 51%, p<0.0001). Therapeutic decision-making based on echo-Doppler findings was similar to that based on hemodynamics.

CONCLUSION

Echo-Doppler hemodynamic monitoring proved accurate in estimating hemodynamic profiles and influenced therapeutic management.

Abnormal Septal Motion Affects Early Diastolic Velocities at the Septal And Lateral Mitral Annulus, and Impacts on Estimation of the Pulmonary Capillary Wedge Pressure

Abnormal motion of the interventricular septum (ASM), seen post cardiac operation, with left bundle branch block or right ventricular pacing, may affect septal mitral annular motion and correlation of the ratio between the velocity of early diastolic mitral inflow and the early diastolic mitral annular velocity (E/Ea) with pulmonary capillary wedge pressure (PCWP). We examined the effect of ASM on the relationship between E/Ea and E/Vp (propagation velocity of mitral inflow) ratios and PCWP in adult patients in the intensive care unit (14 with normal septal motion [NSM], 36 with ASM) undergoing echocardiography and pulmonary artery catheterization. E/Ea correlated well with PCWP during NSM ( r = 0.86 lateral annulus, r = 0.75 septal annulus), but poorly during ASM ( r = 0.36 lateral annulus, r = 0.39 septal annulus). E/Vp correlated poorly with PCWP ( r = 0.05 NSM, r = 0.17 ASM). For patients who are critically ill, E/Vp ratios poorly estimate PCWP. During NSM, E/Ea ratios measured at the lateral or septal annulus correlate well with PCWP. ASM affects E/Ea ratios at both the septal and lateral annulus, making E/Ea ratios unreliable for estimating PCWP in this group.

Morbidity in hospitalized patients receiving human albumin: a meta-analysis of randomized, controlled trials

OBJECTIVE

To determine the effect of albumin administration on morbidity in acutely ill hospitalized patients.

DATA SOURCE

Computer searches of MEDLINE, EMBASE, and the Cochrane Library; hand searches of journals and Index Medicus; inquiries with investigators and fluid product suppliers; and examination of reference lists. No language or time period restrictions were adopted.

STUDY SELECTION

Randomized, controlled trials comparing the administration of albumin with that of crystalloid, no albumin, or lower-dose albumin.

DATA EXTRACTION

Two investigators independently extracted data. The primary endpoint for the meta-analysis was morbidity, defined as the incidence of complications, including death. Trial quality was evaluated by blinding, allocation concealment, presence of morbidity as a study endpoint, and individual patient crossover.

DATA SYNTHESIS

Seventy-one trials were included in the categories of surgery or trauma, burns, hypoalbuminemia, high-risk neonates, ascites, and other indications. The 3,782 randomized patients in the included trials experienced a total of 3,287 complications, including 515 deaths and 2,772 cardiovascular, gastrointestinal, hepatic, infectious, renal, respiratory, and other complications. Albumin significantly reduced overall morbidity, with a risk ratio of 0.92 (confidence interval [CI], 0.86-0.98). Control group albumin dose significantly affected the incidence of complications (p = .002). In 32 trials with no albumin administered to the control group, the risk ratio was 0.77 (CI, 0.67-0.88) compared with 0.89 (CI, 0.80-1.00) in 20 trials with control patients receiving low-dose albumin and 1.07 (CI, 0.96-1.20) in 19 trials with moderate-dose control group albumin.

CONCLUSIONS

Albumin reduces morbidity in acutely ill hospitalized patients. Concomitant administration of albumin in the control group can obscure the effects of albumin on clinical outcome in randomized trials.

Hemodynamic Assessment

Hemodynamic monitoring has become an integral component of the assessment of the critically ill. Any technology used for monitoring is a diagnostic tool and only as good as the provider interpreting the data. The article focuses on providing the practitioner the physiologic basis of the hemodynamic profile to cross the chasm of turning data into clinically useful information. Decision-making models are described to facilitate data synthesis and clinical intervention.

Severity of illness and risk of death associated with pulmonary artery catheter use

OBJECTIVE

To examine the association between the use of the pulmonary artery catheter and mortality rate in critically ill patients with a higher vs. a lower severity of illness.

DESIGN

Observational cohort study.

SETTING

A tertiary care university teaching hospital from March 1988 to March 1998.

PATIENTS

A total of 7,310 critically ill adult patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The main outcome measure was hospital mortality rate, controlled by multivariable logistic regression within four patient groups based on severity of illness. Cutoffs for severity of illness were chosen based on Acute Physiology and Chronic Health Evaluation (APACHE) II score 25th percentiles. Logistic regression analysis demonstrated no increased risk of death associated with exposure to the pulmonary artery catheter in the population as a whole. The associated odds ratio of hospital death for the entire cohort was 1.05 (95% confidence interval, 0.92-1.21). Subgroup analysis of severity of illness revealed the highest risk of death to be associated with the lowest APACHE II score quartile vs. a decreased associated mortality rate with the highest APACHE II score quartile after adjustment with multivariable logistic regression (APACHE II <18: odds ratio, 2.47, 95% confidence interval, 1.27-4.81; APACHE II 18-24: odds ratio, 1.64, 95% confidence interval, 1.24-2.17; APACHE II 25-31: odds ratio, 1.00, 95% confidence interval, 0.80-1.24; APACHE II >31: odds ratio, 0.80, 95% confidence interval, 0.64-1.00).

CONCLUSIONS

The use of the pulmonary artery catheter may decrease mortality rate in the most severely ill while increasing it in a population with a lower severity of illness. These findings underscore the necessity of examining the effect of severity of illness in future randomized controlled trials.