Can postoperative continuous positive airway pressure (CPAP) prevent pulmonary complications after abdominal surgery?

Twenty-four patients underwent elective cholecystectomy. They were randomized into two groups, one consisting of 13 patients having CPAP^* by face-mask for 4 h after surgery and the other, consisting of 11 patients, serving as control. The patients were all given intravenous anesthesia and were manually ventilated during anesthesia without using PEEP. The groups were comparable as concerns sex, age, weight, smoking-habits, preoperative pulmonary status, type of surgery and anesthesia-time. The study showed that both groups had a reduction in VC and PaO₂ and a high percentage of them developed chest X-ray changes. In none of the variables mentioned was there any significant difference between the groups after surgery. Hypoxemia after abdominal surgery can thus not be prevented by only using CPAP for 4 h postoperatively.     

Significance of perioperative goal-directed hemodynamic approach in preventing postoperative complications in patients after cardiac surgery: a meta-analysis and systematic review

Purpose: Goal-directed hemodynamic therapy (GDT) is used to prevent hypoperfusion resulting from surgery. The objective of this study was to analyze the efficacy and importance of perioperative GDT.

Methods: PUBMED, MEDLINE, CENTRAL, and Google Scholar databases were searched until 17 June 2016 using the search terms: cardiac output, cardiac surgical procedures, hemodynamics, goal-directed therapy, and intraoperative. Randomized-controlled trials with pre-emptive hemodynamic intervention for cardiac surgical population versus standard hemodynamic therapy were included.

Results: Nine studies were included with a total of 1148 patients. The overall analysis revealed no significant difference in the all-cause mortality (pooled peto OR =0.58, 95%CI =0.27–1.525, p?=?0.164), duration of mechanical ventilation (pooled difference in mean=??1.48, 95%CI=??3.24 to 0.28, p?=?0.099), or length of intensive care unit (ICU) stay (pooled difference in mean=??9.10, 95%CI=??20.14 to 1.93, p?=?0.106) between patients in the GDT and control groups. Patients in the GDP group were associated with shorter hospital stay than those in the control group (pooled difference in mean=??1.52, 95%CI=??2.31 to ?0.73, p?Conclusion: GDT reduces the length of hospital stay compared with the standard of care. Further studies are necessary to continually assess the benefit of GDT following major surgery.

• Key Messages

• The results of this analysis revealed no significant difference between cardiac surgery patients receiving goal-directed hemodynamic therapy (GDT) or conventional fluid therapy in terms of the all-cause mortality, duration of mechanical intervention, and length of ICU-stay.

• The length of hospital stay was significantly reduced in patients treated with GDT compare to conventional fluid therapy.

• GDT may have limited benefit in reducing mortality; however, the association to shorter length of hospital stay may suggest that better hemodynamic balance can facilitate postoperative recovery.

     

Perioperative goal-directed therapy and postoperative outcomes in patients undergoing high-risk abdominal surgery: a historical-prospective,comparative effectiveness study

IntroductionPerioperative goal-directed therapy (PGDT) may improve postoperative outcome in high-risk surgery patients but its adoption has been slow. In 2012, we initiated a performance improvement (PI) project focusing on the implementation of PGDT during high-risk abdominal surgeries. The objective of the present study was to evaluate the effectiveness of this intervention.MethodsThis is a historical prospective quality improvement study. The goal of this initiative was to standardize the way fluid management and hemodynamic optimization are conducted during high-risk abdominal surgery in the Departments of Anesthesiology and Surgery at the University of California Irvine. For fluid management, the protocol consisted in standardized baseline crystalloid administration of 3 ml/kg/hour and any additional boluses based on PGDT. The impact of the intervention was assessed on the length of stay in the hospital (LOS) and post-operative complications (NSQIP database).ResultsIn the 1 year pre- and post-implementation periods, 128 and 202 patients were included. The average volume of fluid administered during the case was 9.9 (7.1–13.0) ml/kg/hour in the pre-implementation period and 6.6 (4.7–9.5) ml/kg/hour in the post-implementation period (p < 0.01). LOS decreased from 10 (6–16) days to 7 (5–11) days (p = 0.0001). Based on the multiple linear regression analysis, the estimated coefficient for intervention was 0.203 (SE = 0.054, p = 0.0002) indicating that, with the other conditions being held the same, introducing intervention reduced LOS by 18 % (95 % confidence interval 9–27 %). The incidence of NSQIP complications decreased from 39 % to 25 % (p = 0.04).ConclusionThese results suggest that the implementation of a PI program focusing on the implementation of PGDT can transform fluid administration patterns and improve postoperative outcome in patients undergoing high-risk abdominal surgeries.

Trial registration

Clinicaltrials.gov {"type":"clinical-trial","attrs":{"text":"NCT02057653","term_id":"NCT02057653"}}NCT02057653. Registered 17 December 2013.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0945-2) contains supplementary material, which is available to authorized users.     

Early goal-directed therapy after major surgery reduces complications and duration of hospital stay. A randomised,controlled trial [ISRCTN38797445]

Introduction  

Goal-directed therapy (GDT) has been shown to improve outcome when commenced before surgery. This requires pre-operative admission to the intensive care unit (ICU). In cardiac surgery, GDT has proved effective when commenced after surgery. The aim of this study was to evaluate the effect of post-operative GDT on the incidence of complications and duration of hospital stay in patients undergoing general surgery.     

Early goal-directed therapy based on endotracheal bioimpedance cardiography: a prospective,randomized controlled study in coronary surgery

The objective was to compare the impact of an early goal-directed hemodynamic therapy based on cardiac output monitoring (Endotracheal Cardiac Output Monitor, ECOM) with a standard of care on postoperative outcome following coronary surgery. This prospective, controlled, parallel-arm trial randomized 100 elective primary coronary artery bypass grafting patients to a study group (ECOM; n = 50) or a control group (control; n = 50). In the ECOM group, hemodynamic therapy was guided by respiratory stroke volume variation and cardiac index given by the ECOM system. A standard of care was used in the control. Goal-directed therapy was started immediately after induction of anesthesia and continued until arrival in the intensive care unit (ICU). The primary endpoint was the time when patients fulfilled discharge criteria from hospital (possible hospital discharge). Secondary endpoints were the hospital discharge, the time to reach extubation, the length of stay in ICU, the number of major adverse cardiac events, and in-hospital mortality. Patients in the ECOM group received more often fluid loading and dobutamine. The time to reach extubation was reduced in the ECOM group: 510 min [360–1,110] versus 570 min [320–1,520], P = 0.005. No significant differences were found between both groups for possible hospital discharge [Hazard Ratio = 0.96 (95 % CI 0.64–1.45)] and hospital discharge [Hazard Ratio = 1.20 (95 % CI 0.79–1.81)]. A mini-invasive early goal-directed hemodynamic therapy based on ECOM can reduce the time to reach extubation but fails to significantly reduce the length of stay in hospital and the rate of major cardiac morbidity.     

Clinical assessment of peripheral perfusion to predict postoperative complications after major abdominal surgery early: a prospective observational study in adults

Introduction

Altered peripheral perfusion is strongly associated with poor outcome in critically ill patients. We wanted to determine whether repeated assessments of peripheral perfusion during the days following surgery could help to early identify patients that are more likely to develop postoperative complications.

Methods

Haemodynamic measurements and peripheral perfusion parameters were collected one day prior to surgery, directly after surgery (D0) and on the first (D1), second (D2) and third (D3) postoperative days. Peripheral perfusion assessment consisted of capillary refill time (CRT), peripheral perfusion index (PPI) and forearm-to-fingertip skin temperature gradient (T_skin-diff). Generalized linear mixed models were used to predict severe complications within ten days after surgery based on Clavien-Dindo classification.

Results

We prospectively followed 137 consecutive patients, from among whom 111 were included in the analysis. Severe complications were observed in 19 patients (17.0%). Postoperatively, peripheral perfusion parameters were significantly altered in patients who subsequently developed severe complications compared to those who did not, and these parameters persisted over time. CRT was altered at D0, and PPI and T_skin-diff were altered on D1 and D2, respectively. Among the different peripheral perfusion parameters, the diagnostic accuracy in predicting severe postoperative complications was highest for CRT on D2 (area under the receiver operating characteristic curve = 0.91 (95% confidence interval (CI) = 0.83 to 0.92)) with a sensitivity of 0.79 (95% CI = 0.54 to 0.94) and a specificity of 0.93 (95% CI = 0.86 to 0.97). Generalized mixed-model analysis demonstrated that abnormal peripheral perfusion on D2 and D3 was an independent predictor of severe postoperative complications (D2 odds ratio (OR) = 8.4, 95% CI = 2.7 to 25.9; D2 OR = 6.4, 95% CI = 2.1 to 19.6).

Conclusions

In a group of patients assessed following major abdominal surgery, peripheral perfusion alterations were associated with the development of severe complications independently of systemic haemodynamics. Further research is needed to confirm these findings and to explore in more detail the effects of peripheral perfusion–targeted resuscitation following major abdominal surgery.     

Estimation of pulse pressure variation and cardiac output in patients having major abdominal surgery: a comparison between a mobile application for snapshot pulse wave analysis and invasive pulse wave analysis

Pulse pressure variation (PPV) and cardiac output (CO) can guide perioperative fluid management. Capstesia (Galenic App, Vitoria-Gasteiz, Spain) is a mobile application for snapshot pulse wave analysis (PWAsnap) and estimates PPV and CO using pulse wave analysis of a snapshot of the arterial blood pressure waveform displayed on any patient monitor. We evaluated the PPV and CO measurement performance of PWAsnap in adults having major abdominal surgery. In a prospective study, we simultaneously measured PPV and CO using PWAsnap installed on a tablet computer (PPV_PWAsnap, CO_PWAsnap) and using invasive internally calibrated pulse wave analysis (ProAQT; Pulsion Medical Systems, Feldkirchen, Germany; PPV_ProAQT, CO_ProAQT). We determined the diagnostic accuracy of PPV_PWAsnap in comparison to PPV_ProAQT according to three predefined PPV categories and by computing Cohen’s kappa coefficient. We compared CO_ProAQT and CO_PWAsnap using Bland-Altman analysis, the percentage error, and four quadrant plot/concordance rate analysis to determine trending ability. We analyzed 190 paired PPV and CO measurements from 38 patients. The overall diagnostic agreement between PPV_PWAsnap and PPV_ProAQT across the three predefined PPV categories was 64.7% with a Cohen’s kappa coefficient of 0.45. The mean (±?standard deviation) of the differences between CO_PWAsnap and CO_ProAQT was 0.6?±?1.3 L min^??1 (95% limits of agreement 3.1 to ??1.9 L min^??1) with a percentage error of 48.7% and a concordance rate of 45.1%. In adults having major abdominal surgery, PPV_PWAsnap moderately agrees with PPV_ProAQT. The absolute and trending agreement between CO_PWAsnap with CO_ProAQT is poor. Technical improvements are needed before PWAsnap can be recommended for hemodynamic monitoring.

     

Comparison of cardiac output optimization with an automated closed-loop goal-directed fluid therapy versus non standardized manual fluid administration during elective abdominal surgery: first prospective randomized controlled trial

An intraoperative automated closed-loop system for goal-directed fluid therapy has been successfully tested in silico, in vivo and in a clinical case–control matching. This trial compared intraoperative cardiac output (CO) in patients managed with this closed-loop system versus usual practice in an academic medical center. The closed-loop system was connected to a CO monitoring system and delivered automated colloid fluid boluses. Moderate to high-risk abdominal surgical patients were randomized either to the closed-loop or the manual group. Intraoperative final CO was the primary endpoint. Secondary endpoints were intraoperative overall mean cardiac index (CI), increase from initial to final CI, intraoperative fluid volume and postoperative outcomes. From January 2014 to November 2015, 46 patients were randomized. There was a lower initial CI (2.06 vs. 2.51 l min^?1 m^?2, p?=?0.042) in the closed-loop compared to the control group. No difference in final CO and in overall mean intraoperative CI was observed between groups. A significant relative increase from initial to final CI values was observed in the closed-loop but not the control group (+?28.6%, p?=?0.006 vs. +?1.2%, p?=?0.843). No difference was found for intraoperative fluid management and postoperative outcomes between groups. There was no significant impact on the primary study endpoint, but this was found in a context of unexpected lower initial CI in the closed-loop group.Trial registry number ID-RCB/EudraCT: 2013-A00770-45. ClinicalTrials.gov Identifier NCT01950845, date of registration: 17 September 2013.     

Goal-directed intraoperative therapy based on autocalibrated arterial pressure waveform analysis reduces hospital stay in high-risk surgical patients: a randomized,controlled trial

Introduction  

Several studies have shown that goal-directed hemodynamic and fluid optimization may result in improved outcome. However, the methods used were either invasive or had other limitations. The aim of this study was to perform intraoperative goal-directed therapy with a minimally invasive, easy to use device (FloTrac/Vigileo), and to evaluate possible improvements in patient outcome determined by the duration of hospital stay and the incidence of complications compared to a standard management protocol.     

More reliable oximetry reduces the frequency of arterial blood gas analyses and hastens oxygen weaning after cardiac surgery: a prospective,randomized trial of the clinical impact of a new technology

OBJECTIVE: Evaluation of the impact on clinical care of improved, innovative oximetry technology. DESIGN: Randomized, prospective trial. SETTING: Postcardiac surgery intensive care unit in a major teaching hospital. PATIENTS: A total of 86 patients after undergoing coronary artery bypass surgery. INTERVENTIONS: All patients were monitored with two oximeters, one employing conventional oximetry (conventional pulse oximeter, CPO) and one using an improved innovative technology (innovative pulse oximeter, IPO), on different fingers of the same hand. The outputs from both devices were collected continuously by computer, but only one device was randomly selected and displayed for clinicians. MEASUREMENTS AND MAIN RESULTS: The amount and percentage of nonfunctional monitoring time was collected and found to be much greater for the CPO than the IPO (8.7% +/- 16.4% for CPO vs. 1.2% +/- 3.3% for IPO, p =.000256). Time to extubation was not different between the two groups (634 +/- 328 mins for IPO vs. 706 +/- 459 mins for CPO). Clinicians managing patients with the more reliable IPO weaned patients faster to an FIO2 of 0.40 (176 +/- 111 mins for IPO vs. 348 +/- 425 mins for CPO, p =.0125), obtained fewer arterial blood gas measurements (2.7 +/- 1.2 for IPO vs. 4.1 +/- 1.6 for CPO, p =.000015), and made the same number of ventilator changes during this weaning process (2.9 +/- 1.2 for IPO vs. 2.9 +/- 1.7 for CPO). CONCLUSIONS: Provision of more reliable oximetry allows caregivers to act in a more efficient and cost-effective manner in regard to oxygen weaning and use of arterial blood gas measurements. Investigating the effect of a monitor on the process of care, rather than simply its accuracy and precision, is a useful, relevant paradigm for evaluating the value and impact of a new technology.     

Effect of dopexamine on outcome after major abdominal surgery: a prospective, randomized, controlled multicenter study. European Multicenter Study Group on Dopexamine in Major Abdominal Surgery

OBJECTIVE: To test the hypothesis that dopexamine reduces postoperative mortality and morbidity in high-risk, major abdominal surgery patients, when given to fluid-resuscitated patients starting before the operation and continued for 24 hrs after surgery. DESIGN: Prospective, randomized, controlled, double-blind multicenter trial. SETTING: Intensive care units in 13 hospitals from six European countries. PATIENTS: A total of 412 patients with predefined high-risk criteria, undergoing major abdominal surgery with an expected duration of at least 1.5 hrs. INTERVENTIONS: The patients received placebo (n = 140), dopexamine at 0.5 microg/kg/min (n = 135), or dopexamine at 2.0 microg/kg/ min (n = 137) starting after preoperative hemodynamic stabilization and continued for 24 hrs after surgery. MEASUREMENTS AND MAIN RESULTS: The primary outcome variable was mortality at 28 days. Analysis was by intention to treat. Dopexamine had no effect on mortality (at 28 days, 13%, 7%, and 15%, for the groups receiving placebo, dopexamine at 0.5 microg/kg/ min, and dopexamine at 2.0 microg/kg/min, respectively), despite the expected dose-dependent hemodynamic responses. No effect was observed on the occurrence of organ dysfunction, duration of intensive care unit stay, or length of hospital stay. CONCLUSION: We conclude that dopexamine in doses that result in increased cardiac output and oxygen delivery after preoperative stabilization with fluids does not improve outcome after major abdominal surgery compared with fluids alone. Based on post hoc subgroup analysis and stratification according to the number of risk factors, we suggest that the concept should be further tested in patients at higher risk of complications or undergoing emergency surgery.