Effect of Hydroxyethyl Starch vs Saline for Volume Replacement Therapy on Death or Postoperative Complications Among High-Risk Patients Undergoing Major Abdominal Surgery: The FLASH Randomized Clinical Trial.

Importance: It is not known if use of colloid solutions containing hydroxyethyl starch (HES) to correct for intravascular deficits in high-risk surgical patients is either effective or safe. Objective: To evaluate the effect of HES 130/0.4 compared with 0.9% saline for intravascular volume expansion on mortality and postoperative complications after major abdominal surgery. Design, Setting, and Participants: Multicenter, double-blind, parallel-group, randomized clinical trial of 775 adult patients at increased risk of postoperative kidney injury undergoing major abdominal surgery at 20 university hospitals in France from February 2016 to July 2018; final follow-up was in October 2018. Interventions: Patients were randomized to receive fluid containing either 6% HES 130/0.4 diluted in 0.9% saline (n = 389) or 0.9% saline alone (n = 386) in 250-mL boluses using an individualized hemodynamic algorithm during surgery and for up to 24 hours on the first postoperative day, defined as ending at 7:59 am the following day. Main Outcomes and Measures: The primary outcome was a composite of death or major postoperative complications at 14 days after surgery. Secondary outcomes included predefined postoperative complications within 14 days after surgery, durations of intensive care unit and hospital stays, and all-cause mortality at postoperative days 28 and 90. Results: Among 826 patients enrolled (mean age, 68 [SD, 7] years; 91 women [12%]), 775 (94%) completed the trial. The primary outcome occurred in 139 of 389 patients (36%) in the HES group and 125 of 386 patients (32%) in the saline group (difference, 3.3% [95% CI, -3.3% to 10.0%]; relative risk, 1.10 [95% CI, 0.91-1.34]; P = .33). Among 12 prespecified secondary outcomes reported, 11 showed no significant difference, but a statistically significant difference was found in median volume of study fluid administered on day 1: 1250 mL (interquartile range, 750-2000 mL) in the HES group and 1500 mL (interquartile range, 750-2150 mL) in the saline group (median difference, 250 mL [95% CI, 83-417 mL]; P = .006). At 28 days after surgery, 4.1% and 2.3% of patients had died in the HES and saline groups, respectively (difference, 1.8% [95% CI, -0.7% to 4.3%]; relative risk, 1.76 [95% CI, 0.79-3.94]; P = .17). Conclusions and Relevance: Among patients at risk of postoperative kidney injury undergoing major abdominal surgery, use of HES for volume replacement therapy compared with 0.9% saline resulted in no significant difference in a composite outcome of death or major postoperative complications within 14 days after surgery. These findings do not support the use of HES for volume replacement therapy in such patients. Trial Registration: ClinicalTrials.gov Identifier: NCT02502773.

Bioelectrical impedance spectroscopy to estimate fluid balance in critically ill patients.

Fluid management is a crucial issue in intensive-care medicine. This study evaluated the feasibility and reproducibility of bioimpedance spectroscopy to measure body-water composition in critically ill patients, and compared fluid balance and daily changes in total body water (TBW) measured by bioimpedance. This observational study included 25 patients under mechanical ventilation. Fluid balance and bioimpedance measurements were recorded on 3 consecutive days. Whole-body bioimpedance spectroscopy was performed with exact or ideal body weights entered into the device, and with or without ICU monitoring. Reproducibility of bioimpedance spectroscopy was very good in all conditions despite ICU monitoring and mechanical ventilation. Bioimpedance measurements using an ideal body weight varied significantly, making the weighing procedure necessary. Comparison of fluid balance and daily changes in body weight provided the best correlation (ρ = 0.74; P < 0.0001). Daily changes in TBW were correlated with fluid balance (Spearman coefficient ρ = 0.31; P = 0.003) and this correlation was improved after exclusion of patients with a SOFA score >10 (ρ = 0.36; P = 0.05) and with extracorporeal circulation (ρ = 0.50; P = 0.005). Regardless of the technique used to estimate volume status, important limits of agreement were observed. Non-invasive determination of body-water composition using bioimpedance spectroscopy is feasible in critically ill patients but requires knowledge of the patient's weight. The best method to assess volume status after fluid resuscitation and the value gained from information about body composition provided by bioimpedance techniques needs further evaluation.

Benefits of intraoperative analgesia guided by the Analgesia Nociception Index (ANI) in bariatric surgery: An unmatched case-control study.

INTRODUCTION: Analgesia Nociception Index (ANI) has been proposed for the evaluation of the nociception-antinociception balance in the perioperative period. In obese patients, where the management of analgesia may be rendered difficult by pharmacological changes, we hypothesised that the monitoring of analgesia with ANI would reduce intraoperative opioid consumption during bariatric surgery. METHODS: This monocentric, observational, unmatched case-control study aimed to compare perioperative data from obese subjects (body mass index ≥35kgm-2) during bariatric surgery with or without the use of ANI monitoring (ANI+ group versus ANI- group). Intraoperative analgesia was provided by injection of sufentanil, which was performed according to the clinician's assessment in the ANI- group or to the ANI value in the ANI+ group. The primary outcome was the mean hourly intraoperative sufentanil requirement. Secondary outcomes included the need for postoperative morphine titration, incidence of nausea and vomiting, respiratory distress and pain scores in the first 24hours. RESULTS: Between December 2013 and September 2016, 60 obese patients (i.e. 30 per group) were included. The mean hourly consumption of sufentanil was significantly lower in the ANI+ group (0.15±0.05µgkg-1h-1 versus 0.17±0.05µgkg-1h-1, P=0.038). We found no difference between groups regarding the incidence of nausea and vomiting, acute respiratory distress, the need for postoperative morphine titration, or pain scores in the first 24 postoperative hours. CONCLUSION: The use of ANI monitoring might reduce intraoperative consumption of sufentanil during bariatric surgery but does not appear to be accompanied by a reduction in its side effects.