Preoperative routine measurement of NT-proBNP predicts postoperative morbidity after non-cardiac surgery with intermediate or high surgical risk: an observational study

BACKGROUND

Chronic heart failure (HF) is a common clinical condition associated with adverse outcomes in elderly patients undergoing non-cardiac surgery. This study aimed to estimate a clinically applicable NT-proBNP cut-off that predicts postoperative 30-day morbidity in a non-cardiac surgical cohort.

METHODS

One hundred ninety-nine consecutive patients older than 65 years undergoing elective non-cardiac surgery with intermediate or high surgical risk were analysed. Preoperative NT-proBNP was measured, and clinical events were assessed up to postoperative day 30. The primary endpoint was the composite morbidity endpoint (CME) consisting of rehospitalisation, acute decompensated heart failure (ADHF), acute kidney injury (AKI), and infection at postoperative day 30. Secondary endpoints included perioperative fluid balance and incidence, duration, and severity of perioperative hypotension.

RESULTS

NT-proBNP of 443 pg/ml had the highest accuracy in predicting the composite endpoint; a clinical cut-off of 450 pg/ml was implemented to compare clinical endpoints. Although 35.2% of patients had NT-proBNP above the threshold, only 10.6% had a known history of HF. The primary endpoint was the composite morbidity endpoint (CME) consisting of rehospitalisation, acute decompensated heart failure (ADHF), acute kidney injury (AKI), and infection. Event rates were significantly increased in patients with NT-proBNP > 450 pg/ml (70.7% vs. 32.4%, p < 0.001), which was due to the incidence of cardiac rehospitalisation (4.4% vs. 0%, p = 0.018), ADHF (20.1% vs. 4.0%, p < 0.001), AKI (39.8% vs. 8.3%, p < 0.001), and infection (46.3% vs. 24.4%, p < 0.01). Perioperative fluid balance and perioperative hypotension were comparable between groups. Preoperative NT-proBNP > 450 pg/ml was an independent predictor of the CME in a multivariable Cox regression model (hazard ratio 2.92 [1.72-4.94]).

CONCLUSIONS

Patients with NT-proBNP > 450 pg/ml exhibited profoundly increased postoperative morbidity. Further studies should focus on interdisciplinary approaches to improve outcomes through integrated interventions in the perioperative period.

TRIAL REGISTRATION

German Clinical Trials Register: DRKS00027871, 17/01/2022.

Feasibility of Goal-Directed Fluid Therapy in Patients with Transcatheter Aortic Valve Replacement - An Ambispective Analysis

INTRODUCTION

Goal-directed fluid therapy (GDFT) has been shown to reduce postoperative complications. The feasibility of GDFT in transcatheter aortic valve replacement (TAVR) patients under general anesthesia has not yet been demonstrated. We examined whether GDFT could be applied in patients undergoing TAVR in general anesthesia and its impact on outcomes.

METHODS

Forty consecutive TAVR patients in the prospective intervention group with GDFT were compared to 40 retrospective TAVR patients without GDFT. Inclusion criteria were age ≥ 18 years, elective TAVR in general anesthesia, no participation in another interventional study. Exclusion criteria were lack of ability to consent study participation, pregnant or nursing patients, emergency procedures, preinterventional decubitus, tissue and/or extremity ischemia, peripheral arterial occlusive disease grade IV, atrial fibrillation or other severe heart rhythm disorder, necessity of usage of intra-aortic balloon pump. Stroke volume and stroke volume variation were determined with uncalibrated pulse contour analysis and optimized according to a predefined algorithm using 250 ml of hydroxyethyl starch.

RESULTS

Stroke volume could be increased by applying GDFT. The intervention group received more colloids and fewer crystalloids than control group. Total volume replacement did not differ. The incidence of overall complications as well as intensive care unit and hospital length of stay were comparable between both groups. GDFT was associated with a reduced incidence of delirium. Duration of anesthesia was shorter in the intervention group. Duration of the interventional procedure did not differ.

CONCLUSION

GDFT in the intervention group was associated with a reduced incidence of postinterventional delirium.

Intraoperative haemodynamic monitoring and management of adults having non-cardiac surgery: Guidelines of the German Society of Anaesthesiology and Intensive Care Medicine in collaboration with the German Association of the Scientific Medical Societies

Haemodynamic monitoring and management are cornerstones of perioperative care. The goal of haemodynamic management is to maintain organ function by ensuring adequate perfusion pressure, blood flow, and oxygen delivery. We here present guidelines on "Intraoperative haemodynamic monitoring and management of adults having non-cardiac surgery" that were prepared by 18 experts on behalf of the German Society of Anaesthesiology and Intensive Care Medicine (Deutsche Gesellschaft für Anästhesiologie und lntensivmedizin; DGAI).

Survey on the Updated German S3 Guideline for Intensive Care in Cardiac Surgery Patients

BACKGROUND

The German guideline on intensive care treatment of cardiac surgical patients provides evidence-based recommendations on management and monitoring. It remains unclear if, respectively, to which degree the guidelines are implemented into the daily practice. Therefore, this study aims to characterize the implementation of guideline recommendations in German cardiac surgical intensive care units (ICUs).

METHODS

An internet-based online survey (42 questions, 9 topics) was sent to 158 German head physicians of cardiac surgical ICUs. To compare the effect over time, most questions were based on a previously performed survey (2013) after introduction of the last guideline update in 2008.

RESULTS

A total of n = 65 (41.1%) questionnaires were included. Monitoring changed to increased provision of available transesophageal echocardiography specialists in 86% (2013: 72.6%), SvO2 measurement in 93.8% (2013: 55.1%), and electroencephalography in 58.5% (2013: 2.6%). The use of hydroxyethyl starch declined (9.4% vs. 2013: 38.7%), gelatin 4% presented the most administered colloid with 23.4% (2013: 17.4%). Low cardiac output syndrome was primarily treated with levosimendan (30.8%) and epinephrine (23.1%), while norepinephrine (44.6%) and dobutamine (16.9%) represented the most favored drug combination. The main way of distribution was web-based (50.9%), with increasing impact on therapy regimens (36.9% vs. 2013: 24%).

CONCLUSION

Changes were found in all questioned sectors compared with the preceding survey, with persisting variability between ICUs. Recommendations of the updated guideline have increasingly entered clinical practice, with participants valuing the updated publication as clinically relevant.

Goal-directed fluid therapy using uncalibrated pulse contour analysis and balanced crystalloid solutions during hip revision arthroplasty: a quality implementation project

BACKGROUND

To implement a goal-directed fluid therapy (GDFT) protocol using crystalloids in hip revision arthroplasty surgery within a quality management project at a tertiary hospital using a monocentric, prospective observational study.

METHODS

Adult patients scheduled for elective hip revision arthroplasty surgery were screened for inclusion in this prospective study. Intraoperatively stroke volume (SV) was optimized within a previously published protocol using uncalibrated pulse contour analysis and balanced crystalloids. Quality of perioperative GDFT was assessed by protocol adherence, SV increase as well as the rate of perioperative complications. Findings were then compared to two different historical groups of a former trial: one receiving GDFT with colloids (prospective colloid group) and one standard fluid therapy (retrospective control group) throughout surgery. Statistical analysis constitutes exploratory data analyses and results are expressed as median with 25th and 75th percentiles, absolute and relative frequencies, and complication rates are further given with 95% confidence intervals for proportions using the normal approximation without continuity correction.

RESULTS

Sixty-six patients underwent GDFT using balanced crystalloids and were compared to 130 patients with GDFT using balanced colloids and 130 controls without GDFT fluid resuscitation. There was a comparable increase in SV (crystalloids: 65 (54-74 ml; colloids: 67.5 (60-75.25 ml) and total volume infused (crystalloids: 2575 (2000-4210) ml; colloids: 2435 (1760-3480) ml; and controls: 2210 (1658-3000) ml). Overall perioperative complications rates were similar (42.4% (95%CI 30.3-55.2%) for crystalloids and 49.2% (95%CI 40.4-58.1%) for colloids and lower compared to controls: 66.9% (95%CI 58.1-74.9)). Interestingly, a reduced number of hemorrhagic complications was observed within crystalloids: 30% (95%CI 19.6-42.9); colloids: 43% (95%CI 34.4-52.0); and controls: 62% (95%CI 52.6-69.9). There were no differences in the rate of admission to the post-anesthesia care unit or intensive care unit as well as the length of stay.

CONCLUSIONS

Perioperative fluid management using a GDFT protocol with crystalloids in hip revision arthroplasty surgery was successfully implemented in daily clinical routine. Perioperative complications rates were reduced compared to a previous management without GDFT and comparable when using colloids.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01753050.

The use of artificial intelligence and machine learning monitoring to safely administer a fluid-restrictive goal-directed treatment protocol to minimize the risk of transfusion during major spine surgery of a Jehovah’s Witness: a case report

Background

The Hypotension Prediction Index (HPI) displays an innovative monitoring tool which predicts intraoperative hypotension before its onset.

Case presentation

We report the case of an 84-year-old Caucasian woman undergoing major spinal surgery with no possibility for the transfer of blood products given her status as a Jehovah’s Witness. The hemodynamic treatment algorithm we employed was based on HPI and resulted in a high degree of hemodynamic stability during the surgical procedure. Further, the patient was not at risk for either hypo- or hypervolemia, conditions which might have caused dilution anemia. By using HPI as a tool for patient blood management, it was possible to reduce the incidence of intraoperative hypotension to a minimum.

Conclusions

In sum, this HPI-based treatment algorithm represents a useful application for the treatment of complex anesthesia and perioperative patient blood management. It is a simple but powerful extension of standard monitoring for the prevention of intraoperative hypotension.

Vasopressor Therapy in Cardiac Surgery-An Experts' Consensus Statement

Hemodynamic conditions with reduced systemic vascular resistance commonly are observed in patients undergoing cardiac surgery and may range from moderate reductions in vascular tone, as a side effect of general anesthetics, to a profound vasodilatory syndrome, often referred to as vasoplegic shock. Therapy with vasopressors is an important pillar in the treatment of these conditions. There is limited guidance on the appropriate choice of vasopressors to restore and optimize systemic vascular tone in patients undergoing cardiac surgery. A panel of experts in the field convened to develop statements and evidence-based recommendations on clinically relevant questions on the use of vasopressors in cardiac surgical patients, using a critical appraisal of the literature following the GRADE system and a modified Delphi process. The authors unanimously and strongly recommend the use of norepinephrine and/or vasopressin for restoration and maintenance of systemic perfusion pressure in cardiac surgical patients; despite that, the authors cannot recommend either of these drugs with respect to the risk of ischemic complications. The authors unanimously and strongly recommend against using dopamine for treating post-cardiac surgery vasoplegic shock and against using methylene blue for purposes other than a rescue therapy. The authors unanimously and weakly recommend that clinicians consider early addition of a second vasopressor (norepinephrine or vasopressin) if adequate vascular tone cannot be restored by a monotherapy with either norepinephrine or vasopressin and to consider using vasopressin as a first-line vasopressor or to add vasopressin to norepinephrine in cardiac surgical patients with pulmonary hypertension or right-sided heart dysfunction.

Management of perioperative volume therapy - monitoring and pitfalls

Over 300 million surgical procedures are performed every year worldwide. Anesthesiologists play an important role in the perioperative process by assessing the overall risk of surgery and aim to reduce the risk of complications. Perioperative hemodynamic and volume management can help to improve outcomes in perioperative patients. There has been ongoing discussion about goal-directed therapy. However, there is a consensus that fluid overload and severe fluid depletion in the perioperative period are harmful and can lead to adverse outcomes. This article provides an overview of how to evaluate the fluid responsiveness of patients, details which parameters could be used, and what limitations should be noted.

[S3 guidelines on intensive medical care of cardiac surgery patients : Hemodynamic monitoring and cardiovascular system-an update]

An update of the S3- guidelines for treatment of cardiac surgery patients in the intensive care unit, hemodynamic monitoring and cardiovascular system was published by the Association of Scientific Medical Societies in Germany (AWMF) in January 2018. This publication updates the guidelines from 2006 and 2011. The guidelines include nine sections that in addition to different methods of hemodynamic monitoring also reviews the topic of volume therapy as well as vasoactive and inotropic drugs. Furthermore, the guidelines also define the goals for cardiovascular treatment. This article describes the most important innovations of these comprehensive guidelines.

Implementation of goal-directed fluid therapy during hip revision arthroplasty: a matched cohort study

Background

Several randomized controlled trials (RCTs) have demonstrated that intraoperative goal-directed fluid therapy (GDFT) can decrease postsurgical complications in patients undergoing major abdominal surgery. However, very few studies have demonstrated the value of goal-directed therapy (GDT) in patients undergoing orthopaedic surgery and confirmed it is as useful in real-life conditions. Therefore, we initiated a GDFT implementation programme in patients undergoing hip revision arthroplasty in order to assess its effects on postoperative complications (e.g. infection, cardiac, neurological, renal) (primary outcome) and hospital and intensive care unit (ICU) length of stay (secondary outcomes).

Methods

We developed a GDFT protocol for the haemodynamic management of patients undergoing hip revision arthroplasty. The GDFT protocol was based on continuous monitoring and optimization of stroke volume during the surgical procedure. From December 2012 and for a period of 17 months, 130 patients were treated according to the GDFT protocol (GDFT group). The pre-, intra-, and postoperative characteristics of patients from the GDFT group were compared to those of 130 historical matched patients (control group) who had the same surgery between January 2011 and August 2012.

Results

Patients from the GDFT and from the control group were comparable in terms of age, comorbidities, and P-POSSUM score. Duration of anaesthesia and surgery were also comparable. The GDFT group had a significantly lower morbidity rate (49.2 vs. 66.9%; p = 0.006) and a shorter median hospital length of stay (11 days (9–15) vs. 9 days (8–12); p = 0.003) than the control group. Patients from the control group post-anaesthesia care unit (PACU)/ICU stayed significantly longer at PACU/ICU than patients from the GDFT group (control group vs. GDFT group, 960 min (360–1210) vs. 400 min (207–825); p < 0.001) Patients from the GDFT group received less crystalloids but more colloids during surgery. They also received more often inotropic therapy.

Conclusions

In patients undergoing hip revision arthroplasty, the implementation of GDT as a new standard operating procedure was successful and associated with reduced postsurgical complications, most importantly a reduction in postoperative bleeding as well as hospital and ICU stay.

Trial registration

ClinicalTrials.gov, NCT01753050

Electronic supplementary material

The online version of this article (doi:10.1186/s13741-016-0056-x) contains supplementary material, which is available to authorized users.

Comparison of the non-invasive Nexfin® monitor with conventional methods for the measurement of arterial blood pressure in moderate risk orthopaedic surgery patients

Objective

Continuous invasive arterial blood pressure (IBP) monitoring remains the gold standard for BP measurement, but traditional oscillometric non-invasive intermittent pressure (NIBP) measurement is used in most low-to-moderate risk procedures. This study compared non-invasive continuous arterial BP measurement using a Nexfin® monitor with NIBP and IBP monitors.

Methods

This was a single-centre, prospective, pilot study in patients scheduled for elective orthopaedic surgery. Systolic BP, diastolic BP and mean arterial blood pressure (MAP) were measured by Nexfin®, IBP and NIBP at five intraoperative time-points. Pearson correlation coefficients, Bland–Altman plots and trending ability of Nexfin® measurements were used as criteria for success in the investigation of measurement reliability.

Results

A total of 20 patients were enrolled in the study. For MAP, there was a sufficient correlation between IBP/Nexfin® (Pearson = 0.75), which was better than the correlation between IBP/NIBP (Pearson = 0.70). Bland–Altman analysis of the data showed that compared with IBP, there was a higher percentage error for MAP_NIBP (30%) compared with MAP_Nexfin® (27%). Nexfin® and NIBP underestimated systolic BP; NIBP also underestimated diastolic BP and MAP. Trending ability for MAP_Nexfin® and MAP_NIBP were comparable to IBP.

Conclusion

Non-invasive BP measurement with Nexfin® was comparable with IBP and tended to be more precise than NIBP.

[Venous saturation : Between oxygen delivery and consumption]

Venous saturation is an important parameter to assess the ratio between oxygen delivery and oxygen consumption for both intensive care medicine and during perioperative care. Mixed venous saturation (SvO₂) is the most reliable parameter in this setting. Due to the high invasiveness of measuring mixed venous saturation, the less invasive central venous saturation (ScvO₂) has been entrenched for determining the balance of oxygen delivery and consumption. However, central venous saturation is inferior compared to mixed venous saturation as it does not cover the lower part of the body, including splanchnic perfusion. Nevertheless, studies have shown that central venous saturation is a reliable marker for goal-directed therapy in intensive care medicine, especially in patients with septic or hemorrhagic shock. Furthermore, central venous saturation has deep impact as a prognostic factor concerning morbidity and mortality. It has to be mentioned that not only decreased venous saturations but also elevated venous saturations are associated with poor outcome. Besides mixed venous and central venous saturation, intensivists and anesthesiologists focus on the central venous-arterial pCO₂ difference (dCO₂). An elevated dCO₂ is associated with poor outcome in patients after cardiac surgery or patients with sepsis. Yet, further investigations have to be performed to implement the dCO₂ as a reliable marker in daily routine.

Prevalence, Diagnosis, Perioperative Monitoring and Treatment of Right Ventricular Dysfunction and/or Pulmonary Arterial Hypertension in Cardiac Surgical Patients in Germany—A Postal Survey

Background Sparse data are available on the prevalence of right ventricular dysfunction and/or pulmonary arterial hypertension in patients scheduled for cardiac surgery in Germany as well as on the intensity and modalities used for diagnosis, perioperative monitoring, and treatment of these comorbidities.

Methods A postal survey including questions on the prevalence of preoperative right ventricular dysfunction and/or pulmonary arterial hypertension in patients undergoing cardiac surgery in 2009 was sent to 81 German heart centers. Total 47 of 81 (58%) heart centers returned the questionnaires. The centers reported data on 51,095 patients, and 49.8% of the procedures were isolated coronary artery bypass grafting.

Results Data on the prevalence of preoperative pulmonary hypertension and/or right ventricular dysfunction were not available in 54% and 64.6% of centers. In the remaining hospitals, 19.5% of patients presented right heart dysfunction and 10% pulmonary arterial hypertension. Preoperative echocardiography was performed in only 45.3% of the coronary artery bypass grafting cases. Preoperative pharmacologic treatment of pulmonary hypertension or right ventricular dysfunction with oral sildenafil, inhaled prostanoids, or nitric oxide was initiated in 71% and 95.7% of the centers, respectively. Intra- and postoperative treatment was most frequently accomplished with phosphodiesterase-III inhibitors.

Conclusion The prevalence of preoperative right heart dysfunction and pulmonary arterial hypertension in cardiac surgical patients in Germany seems to be substantial. However, in more than 50% of the patients, no preoperative data on right ventricular function and pulmonary arterial pressure are available. This may lead to underestimation of perioperative risk and inappropriate management of this high-risk population.

Feasibility and influence of hTEE monitoring on postoperative management in cardiac surgery patients

Monoplane hemodynamic TEE (hTEE) monitoring (ImaCor(®) ClariTEE(®)) might be a useful alternative to continuously evaluate cardiovascular function and we aimed to investigate the feasibility and influence of hTEE monitoring on postoperative management in cardiac surgery patients. After IRB approval we reviewed the electronic data of cardiac surgery patients admitted to our intensive care between 01/01/2012 and 30/06/2013 in a case-controlled matched-pairs design. Patients were eligible for the study when they presented a sustained hemodynamic instability postoperatively with the clinical need of an extended hemodynamic monitoring: (a) hTEE (hTEE group, n = 18), or (b) transpulmonary thermodilution (control group, n = 18). hTEE was performed by ICU residents after receiving an approximately 6-h hTEE training session. For hTEE guided hemodynamic optimization an institutional algorithm was used. The hTEE probe was blindly inserted at the first attempt in all patients and image quality was at least judged to be adequate. The frequency of hemodynamic examinations was higher (ten complete hTEE examinations every 2.6 h) in contrast to the control group (one examination every 8 h). hTEE findings, including five unexpected right heart failure and one pericardial tamponade, led to a change of current therapy in 89% of patients. The cumulative dose of epinephrine was significantly reduced (p = 0.034) and levosimendan administration was significantly increased (p = 0.047) in the hTEE group. hTEE was non-inferior to the control group in guiding norepinephrine treatment (p = 0.038). hTEE monitoring performed by ICU residents was feasible and beneficially influenced the postoperative management of cardiac surgery patients.

High central venous saturation after cardiac surgery is associated with increased organ failure and long-term mortality: an observational cross-sectional study

INTRODUCTION

Central venous saturation (ScvO2) monitoring has been suggested to address the issue of adequate cardiocirculatory function in the context of cardiac surgery. The aim of this study was to determine the impact of low (L) (<60%), normal (N) (60%-80%), and high (H) (>80%) ScvO2 measured on intensive care unit (ICU) admission after cardiac surgery.

METHODS

We conducted a retrospective, cross-sectional, observational study at three ICUs of a university hospital department for anaesthesiology and intensive care. Electronic patient records of all adults who underwent cardiac surgery between 2006 and 2013 and available admission measurements of ScvO2 were examined. Patients were allocated to one of three groups according to first ScvO2 measurement after ICU admission: group L (<60%), group N (60%-80%), and group H (>80%). Primary end-points were in-hospital and 3-year follow-up survival.

RESULTS

Data from 4,447 patients were included in analysis. Low and high initial measurements of ScvO2 were associated with increased in-hospital mortality (L: 5.6%; N: 3.3%; H: 6.8%), 3-year follow-up mortality (L: 21.6%; N: 19.3%; H: 25.8%), incidence of post-operative haemodialysis (L: 11.5%; N: 7.8%; H: 15.3%), and prolonged hospital length of stay (L: 13 days, 9-22; N: 12 days, 9-19; H: 14 days, 9-21). After adjustment for possible confounding variables, an initial ScvO2 above 80% was associated with adjusted hazard ratios of 2.79 (95% confidence interval (CI) 1.565-4.964, P <0.001) for in-hospital survival and 1.31 (95% CI 1.033-1.672, P = 0.026) for 3-year follow-up survival.

CONCLUSIONS

Patients with high ScvO2 were particularly affected by unfavourable outcomes. Advanced haemodynamic monitoring may help to identify patients with high ScvO2 who developed extraction dysfunction and to establish treatment algorithms to improve patient outcome in these patients.

[Echocardiography for hemodynamic monitoring on ICU?]

A goal-directed hemodynamic therapy (GDT) using volume substitution and/or cardiovascular agents in order to increase stroke volume and consecutively tissue oxygenation has been shown to reduce perioperative complications. Previous hemodynamic monitoring devices mostly are only able to detect a restriction in several parameters of cardiovascular function not always diagnostically conclusive to their pathophysiological cause. However, this is mandatory for GDT. In this context, discontinuous transthoracic (TTE) and transesophageal (TEE) echocardiography is gaining clinical relevance. In addition, recently there exists the opportunity to perform a continuous hemodynamic focused transesophageal echocardiography ("hemodynamic TEE", hTEE) via a miniaturized monoplane probe. With its flexible probe tip the three most important two-dimensional views of the heart can be obtained to differentiate between aforementioned pathophysiological causes of a low cardiac output syndrome. It is introduced orally in the patient's esophagus and can remain up to 72 hours in situ. First clinical reports/studies were able to demonstrate that a short intensive training programme for physicians unexperienced in echocardiography was sufficient to adequately initiate GDT. However, further studies have to prove the clinical feasibility and the positive effect on patient's outcome.

Incidence of postoperative death and acute kidney injury associated with i.v. 6% hydroxyethyl starch use: systematic review and meta-analysis

BACKGROUND

Trials suggest that the use of i.v. hydroxyethyl starch (HES) solutions is associ-ated with increased risk of death and acute kidney injury (AKI) in critically ill patients. It is uncertain whether similar adverse effects occur in surgical patients.

METHODS

Systematic review and meta-analysis of trials in which patients were randomly allocated to 6% HES solutions or alternative i.v. fluids in patients undergoing surgery. Ovid Medline, Embase, Cinhal, and Cochrane Database of Systematic Reviews were searched for trials comparing 6% HES with clinically relevant non-starch comparator. The primary end-point was hospital mortality. Secondary endpoints were requirement for renal replacement therapy (RRT) and author-defined AKI. Pre-defined subgroups were cardiac and non-cardiac surgery.

RESULTS

Four hundred and fifty-six papers were identified; of which 19 met the inclusion criteria. In total, 1567 patients were included in the analysis. Dichotomous outcomes were expressed as a difference of proportions [risk difference (RD)]. There was no difference in hospital mortality [RD 0.00, 95% confidence interval (CI) -0.02, 0.02], requirement for RRT (RD -0.01, 95% CI -0.04, 0.02), or AKI (RD 0.02, 95% CI -0.02 to 0.06) between compared arms overall or in predefined subgroups.

CONCLUSIONS

We did not identify any differences in the incidence of death or AKI in surgical patients receiving 6% HES. Included studies were small with low event rates and low risk of heterogeneity. Narrow CIs suggest that these findings are valid. Given the absence of demonstrable benefit, we are unable to recommend the use of 6% HES solution in surgical patients.

Bench-to-bedside review: functional hemodynamics during surgery - should it be used for all high-risk cases?

The administration of a fluid bolus is done frequently in the perioperative period to increase the cardiac output. Yet fluid loading fails to increase the cardiac output in more than 50% of critically ill and surgical patients. The assessment of fluid responsiveness (the slope of the left ventricular function curve) prior to fluid administration may thus not only help in detecting patients in need of fluids but may also prevent unnecessary and harmful fluid overload. Unfortunately, commonly used hemodynamic parameters, including the cardiac output itself, are poor predictors of fluid responsiveness, which is best assessed by functional hemodynamic parameters. These dynamic parameters reflect the response of cardiac output to a preload-modifying maneuver (for example, a mechanical breath or passive leg-raising), thus providing information about fluid responsiveness without the actual administration of fluids. All dynamic parameters, which include the respiratory variations in systolic blood pressure, pulse pressure, stroke volume and plethysmographic waveform, have been repeatedly shown to be superior to commonly used static preload parameters in predicting the response to fluid loading. Within their respective limitations, functional hemodynamic parameters should be used to guide fluid therapy as part of or independently of goal-directed therapy strategies in the perioperative period.

Perioperative gene expression analysis for prediction of postoperative sepsis

BACKGROUND

Postoperative sepsis is one of the main causes of death after major abdominal surgery; however, the immunologic factors contributing to the development of sepsis are not completely understood. In this study, we evaluated gene expression in patients who developed postoperative sepsis and in patients with an uncomplicated postoperative course.

METHODS

We enrolled 220 patients in a retrospective matched-pair, case-control pilot study to investigate the perioperative expression of 23 inflammation-related genes regarding their properties for predicting postoperative sepsis. Twenty patients exhibiting symptoms of sepsis in the first 14 days after surgery (case group) were matched with 20 control patients with an uncomplicated postoperative course. Matching criteria were sex, age, main diagnosis, type of surgery, and concomitant diseases. Blood samples were drawn before surgery and on the first and second postoperative days. Relative gene expression was analyzed with real-time reverse-transcription PCR.

RESULTS

Significant differences (P < 0.005) in gene expression between the 2 groups were observed for IL1B (interleukin 1, beta), TNF [tumor necrosis factor (TNF superfamily, member 2)], CD3D [CD3d molecule, delta (CD3-TCR complex)], and PRF1 [perforin 1 (pore forming protein)]. Logistic regression analysis and a subsequent ROC curve analysis revealed that the combination of TNF, IL1B, and CD3D expression had a specificity and specificity of 90% and 85%, respectively, and predicted exclusion of postoperative sepsis with an estimated negative predictive value of 98.1%.

CONCLUSIONS

These data suggest that gene expression analysis may be an effective tool for differentiating patients at high and low risk for sepsis after abdominal surgery.