Meta-analysis of standard, restrictive and supplemental fluid administration in colorectal surgery

Perioperative Fluid Management

The medical complexity of the geriatric patients has been steadily rising. Still, as outcomes of surgical procedures in the older adults are improving, centers are pushing boundaries. There is also a growing appreciation of the importance of perioperative fluid management on postoperative outcomes, especially in the older adults. Optimal fluid management in this cohort is challenging due to the combination of age-related physiological changes in organ function, increased comorbid burden, and larger fluid shifts during more complex surgical procedures. The current state-of-the-art approach to fluid management in the perioperative period is outlined.

Higher compliance with the enhanced recovery after surgery protocol improves postoperative recovery and 6-month mortality in upper gastrointestinal surgery

Introduction

The enhanced recovery after surgery (ERAS) protocol has been proven to accelerate recovery without increasing morbidity, but few data are available from developing countries. We aimed to demonstrate the correlation between compliance with the ERAS protocol and short-term outcomes in upper gastrointestinal (UGI) surgery.

Materials and Methods

Patients that underwent esophageal and gastric surgeries during March 2019 to June 2021 were prospectively enrolled in this nonrandomized cohort study. The ERAS protocol was applied based on patient-doctor agreement. Patients were categorized into conventional care (CC), moderate-compliance (MC), and high-compliance (HC) groups. Short-term outcomes including gastrointestinal (GI) function recovery, length of hospital stay (LOS), postoperative complications and mortality rate were compared.

Results

158 patients were enrolled: 58 in the CC, 33 in the MC, and 67 in the HC group. The HC group demonstrated reduced time to tolerate oral diet (8 vs 7 vs 3 days; p = 0.034), recovery of GI function (72 vs 96 vs 61 h; p = 0.001) and median LOS (12.5 vs 10 vs 6 days; p < 0.001). Postoperative overall (p = 0.08) and major complications (p = 0.09) were not significantly different. Non-surgical complications were lower in the HC group (31.0 % vs 54.5 % vs 25.4 %; p = 0.013). The 28-day readmission rate was not different (8.6 % vs 3.0 % vs 1.5 %; p = 0.14). The 30-day postoperative mortality was not different (0 % vs 3.1 % vs 0 %; p = 0.15), but the 6-month mortality rate was significantly lower in the HC group (13.8 % vs 15.2 % vs 0 %; p < 0.001).

Conclusion

The level of compliance with the ERAS protocol is associated with improved short-term postoperative outcome in UGI surgery. High compliance patients recovered faster, were discharged sooner, and had better 6-month survival.

Enhanced recovery after fetal spina bifida surgery: global practice

OBJECTIVES

Enhanced recovery after surgery (ERAS) protocols are multimodal evidence-based care plans that have been adopted for multiple surgical procedures to promote faster and better patient recovery and shorter hospitalization. This study aimed to explore whether worldwide fetal therapy centers offering prenatal myelomeningocele repair implement the ERAS principles and to provide recommendations for improved perioperative management of patients.

METHODS

In this survey study, a total of 53 fetal therapy centers offering prenatal surgery for open spina bifida were identified and invited to complete a digital questionnaire covering their pre-, intra- and postoperative management. An overall score was calculated per center based on compliance with 20 key ERAS principles, extrapolated from ERAS guidelines for Cesarean section, gynecological oncology and colorectal surgery. Each item was awarded a score of 1 or 0, depending, respectively, on whether the center did or did not comply with that principle, with a maximum score of 20.

RESULTS

The questionnaire was completed by 46 centers in 17 countries (response rate, 87%). In total, 22 (48%) centers performed exclusively open fetal surgery (laparotomy and hysterotomy), whereas 14 (30%) offered both open and fetoscopic procedures and 10 (22%) used only fetoscopy. The perioperative management of patients undergoing fetoscopic and open surgery was very similar. The median ERAS score was 12 (range, 8-17), with a mean ± SD of 12.5 ± 2.4. Center compliance was the highest for the use of regional anesthesia (98%), avoidance of bowel preparation (96%) and thromboprophylaxis (96%), while the lowest compliance was observed for preoperative carbohydrate loading (15%), a 2-h fasting period for clear fluids (20%), postoperative nausea and vomiting prevention (33%) and early feeding (35%). ERAS scores were similar in centers with a short (2-5 days), medium (6-10 days) and long (≥ 11 days) hospital stay (mean ± SD, 12.9 ± 2.4, 12.1 ± 2.0 and 10.3 ± 3.2, respectively, P = 0.15). Furthermore, there was no significant association between ERAS score and surgical technique or case volume.

CONCLUSIONS

The perioperative management of fetal spina bifida surgery is highly variable across fetal therapy centers worldwide. Standardized protocols integrating ERAS principles may improve patient recovery, reduce maternal morbidity and shorten the hospital stay after fetal spina bifida surgery. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

In vivo effects of balanced, low molecular 6% and 10% hydroxyethyl starch compared with crystalloid volume replacement on the coagulation system in major pancreatic surgery-a sub-analysis of a prospective double-blinded, randomized controlled trial

BACKGROUND

The outcome of patients undergoing major surgery treated with HES for hemodynamic optimization is unclear. This post-hoc analysis of a randomized clinical pilot trial investigated the impact of low-molecular balanced HES solutions on the coagulation system, blood loss and transfusion requirements.

METHODS

The Trial was registered: EudraCT 2008-004175-22 and ethical approval was provided by the ethics committee of Berlin. Patients were randomized into three groups receiving either a 10% HES 130/0.42 solution, a 6% HES 130/0.42 solution or a crystalloid following a goal-directed hemodynamic algorithm. Endpoints were parameters of standard and viscoelastic coagulation laboratory, blood loss and transfusion requirements at baseline, at the end of surgery (EOS) and the first postoperative day (POD 1).

RESULTS

Fifty-two patients were included in the analysis (HES 10% (n = 15), HES 6% (n = 17) and crystalloid (n = 20)). Fibrinogen decreased in all groups at EOS (HES 10% 338 [298;378] to 192 [163;234] mg dl-1, p<0.01, HES 6% 385 [302;442] to 174 [163;224] mg dl-1, p<0.01, crystalloids 408 [325;458] to 313 [248;370] mg dl-1, p = 0.01). MCF FIBTEM was decreased for both HES groups at EOS (HES 10%: 20.5 [16.0;24.8] to 6.5 [5.0;10.8] mm, p = <0.01; HES 6% 27.0 [18.8;35.2] to 7.0 [5.0;19.0] mm, p = <0.01). These changes did not persist on POD 1 for HES 10% (rise to 16.0 [13.0;24.0] mm, p = 0.88). Blood loss was not different in the groups nor transfusion requirements.

CONCLUSION

Our data suggest a stronger but transient effect of balanced, low-molecular HES on the coagulation system. Despite the decline of the use of artificial colloids in clinical practice, these results may help to inform clinicians who use HES solutions.

Feasibility of the ERAS (Enhanced Recovery After Surgery) Protocol in Patients Undergoing Gastrointestinal Cancer Surgeries in a Tertiary Care Hospital-A Prospective Interventional Study

Enhanced Recovery After Surgery (ERAS) protocols have emerged as a promising approach to optimize perioperative care and improve outcomes in various surgical specialties. Despite feasibility studies on ERAS in various surgeries, there remains a paucity of research focusing on gastrointestinal cancer surgeries in the Indian context. The primary objective is to evaluate the compliance rate of the ERAS protocol and secondary objectives include the compliance rate of individual components of the protocol, the complications, the length of hospital stay, and the challenges faced during implementation in patients undergoing gastrointestinal cancer surgeries in our tertiary care cancer center. In this prospective interventional study (CTRI/2022/04/041657; registered on 05/04/2022), we evaluated 50 patients aged 18 to 70 years undergoing surgery for gastrointestinal malignancies and implemented a refined ERAS protocol tailored to our institutional resources and conditions based on standard ERAS society recommendations for gastrointestinal surgeries and specific recommendations for colorectal, pancreatic, and esophageal surgeries.Our study's mean overall compliance rate with the ERAS protocol was 88.54%. We achieved a compliance rate of 91.98%, 81.66%, and 92.00% for pre-operative, intraoperative, and post-operative components respectively. Fourteen (28%) patients experienced complications during the study. The median length of stay was 6.5 days (5.25-8). Challenges were encountered during the preoperative, intraoperative, and postoperative phases. The study highlighted the feasibility of implementing the ERAS protocol in a cancer institute, but specific challenges need to be addressed for its optimal success in gastrointestinal cancer surgeries.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13193-024-01897-y.

Perioperative acute kidney injury: Current knowledge and the role of anaesthesiologists

Background

Among the different types of perioperative organ injury, acute kidney injury (AKI) occurs frequently and is consistently associated with increased rates of mortality and mortality. Despite development of many clinical trials to assess perioperative interventions, reliable means to prevent or reverse AKI are still lacking.

Objectives

This narrative review discusses recent literature on modifiable risk factors, current approaches to prevention and potential directions for future research.

Methods

A Pubmed search with the relevant keywords was done for articles published in the last 10 years.

Results

New insights into preoperative identification and optimisation, intraoperative strategies, including the choice of anaesthetic, haemodynamic and fluid management, have been made, with the aim of preventing perioperative AKI.

Conclusion

A patient-centric multidisciplinary approach is essential to protect kidney function of patients going for surgery. Much can be done by anaesthesiologists perioperatively, to reduce the risk of development of AKI, especially in susceptible patients. There is a need for further multicentred trials to enhance the currently generic perioperative recommendations.

Perioperative Fluid Management

The medical complexity of the geriatric patients has been steadily rising. Still, as outcomes of surgical procedures in the elderly are improving, centers are pushing boundaries. There is also a growing appreciation of the importance of perioperative fluid management on postoperative outcomes, especially in the elderly. Optimal fluid management in this cohort is challenging due to the combination of age-related physiological changes in organ function, increased comorbid burden, and larger fluid shifts during more complex surgical procedures. The current state-of-the-art approach to fluid management in the perioperative period is outlined.

Coffee administration to promote return of bowel function after small bowel resection: A randomized, controlled trial

BACKGROUND

Prolonged ileus occurs in 10%-24% of patients undergoing abdominal surgery. Several trials have found coffee administration reduces postoperative ileus, but this has not been evaluated for small bowel resection.

METHODS

Following small bowel resection, patients were randomized to caffeinated coffee or warm water three times a day until the time of first flatus or first bowel movement. Primary outcomes were time from end of procedure to: 1) nasogastric tube removal; and 2) when the discharge order was written. Outcomes were compared using Kaplan-Meier survival curves.

RESULTS

Thirty-nine patients received coffee and 40 water. Median days to nasogastric tube removal was 3.4 for the coffee and 4.0 for the water groups (p = 0.002). Median days to discharge order was 6.7 for the coffee and 7.7 for the water groups (p = 0.01).

CONCLUSION

Coffee was safe and decreased time to nasogastric tube removal and hospital stay in patients undergoing small bowel resection.

Anesthesia management and outcomes of gynecologic oncology surgery

OBJECTIVES

This study assessed postoperative mortality, morbidity, and complications associated with anesthesia administration for gynecologic oncology abdominal surgery and investigated the risk factors for the development of these complications.

METHODS

We conducted a retrospective cohort study analyzing the data of patients who underwent elective gynecologic oncology surgery between 2010 and 2017. The demographic data; comorbidities; preoperative anemia; Charlson Comorbidity Index; anesthesia management; complications; preoperative, intraoperative, and postoperative periods; mortality; and morbidity were investigated. The patients were classified as surviving or deceased. Subgroup analyses of patients with endometrial, ovarian, cervical, and other cancers were performed.

RESULTS

We analyzed 416 patients; 325 survived and 91 were deceased. The postoperative chemotherapy rates (p < 0.001), and postoperative blood transfusion rates (p = 0.010) were significantly higher in the deceased group, while the preoperative albumin levels were significantly lower in the deceased group (p < 0.001). Infused colloid amount was higher in the deceased group of endometrial (p = 0.018) and ovarian cancers (p = 0.017).

CONCLUSIONS

Perioperative patient management for cancer surgery requires a multidisciplinary approach led by an anesthesiologist and surgeon. Any improvement in the duration of hospital stay, morbidity, or recovery rate depends on the success of the multidisciplinary team.

Fluid management strategies and their interaction with mechanical ventilation: from experimental studies to clinical practice

Patients on mechanical ventilation may receive intravenous fluids via restrictive or liberal fluid management. A clear and objective differentiation between restrictive and liberal fluid management strategies is lacking in the literature. The liberal approach has been described as involving fluid rates ranging from 1.2 to 12 times higher than the restrictive approach. A restrictive fluid management may lead to hypoperfusion and distal organ damage, and a liberal fluid strategy may result in endothelial shear stress and glycocalyx damage, cardiovascular complications, lung edema, and distal organ dysfunction. The association between fluid and mechanical ventilation strategies and how they interact toward ventilator-induced lung injury (VILI) could potentiate the damage. For instance, the combination of a liberal fluids and pressure-support ventilation, but not pressure control ventilation, may lead to further lung damage in experimental models of acute lung injury. Moreover, under liberal fluid management, the application of high positive end-expiratory pressure (PEEP) or an abrupt decrease in PEEP yielded higher endothelial cell damage in the lungs. Nevertheless, the translational aspects of these findings are scarce. The aim of this narrative review is to provide better understanding of the interaction between different fluid and ventilation strategies and how these interactions may affect lung and distal organs. The weaning phase of mechanical ventilation and the deresuscitation phase are not explored in this review.

Impact of Intraoperative Fluid Balance and Norepinephrine on Postoperative Acute Kidney Injury after Cystectomy and Urinary Diversion over Two Decades: A Retrospective Observational Cohort Study

The use of norepinephrine and the restriction of intraoperative hydration have gained increasing acceptance over the last few decades. Recently, there have been concerns regarding the impact of this approach on renal function. The objective of this study was to examine the influence of norepinephrine, intraoperative fluid administration and their interaction on acute kidney injury (AKI) after cystectomy. In our cohort of 1488 consecutive patients scheduled for cystectomies and urinary diversions, the overall incidence of AKI was 21.6% (95%-CI: 19.6% to 23.8%) and increased by an average of 0.6% (95%-CI: 0.1% to 1.1%, p = 0.025) per year since 2000. The fluid and vasopressor regimes were characterized by an annual decrease in fluid balance (-0.24 mL·kg^-1·h^-1, 95%-CI: -0.26 to -0.22, p < 0.001) and an annual increase in the amount of norepinephrine of 0.002 µg·kg^-1·min^-1 (95%-CI: 0.0016 to 0.0024, p < 0.001). The interaction between the fluid balance and norepinephrine levels resulted in a U-shaped association with the risk of AKI; however, the magnitude and shape depended on the reference categories of confounders (age and BMI). We conclude that decreased intraoperative fluid balance combined with increased norepinephrine administration was associated with an increased risk of AKI. However, other potential drivers of the observed increase in AKI incidence need to be further investigated in the future.

Biological impact of restrictive and liberal fluid strategies at low and high PEEP levels on lung and distal organs in experimental acute respiratory distress syndrome

Background: Fluid regimens in acute respiratory distress syndrome (ARDS) are conflicting. The amount of fluid and positive end-expiratory pressure (PEEP) level may interact leading to ventilator-induced lung injury (VILI). We therefore evaluated restrictive and liberal fluid strategies associated with low and high PEEP levels with regard to lung and kidney damage, as well as cardiorespiratory function in endotoxin-induced ARDS.

Methods: Thirty male Wistar rats received an intratracheal instillation of Escherichia coli lipopolysaccharide. After 24 h, the animals were anesthetized, protectively ventilated (V_T = 6 ml/kg), and randomized to restrictive (5 ml/kg/h) or liberal (40 ml/kg/h) fluid strategies (Ringer lactate). Both groups were then ventilated with PEEP = 3 cmH₂O (PEEP3) and PEEP = 9 cmH₂O (PEEP9) for 1 h (n = 6/group). Echocardiography, arterial blood gases, and lung mechanics were evaluated throughout the experiments. Histologic analyses were done on the lungs, and molecular biology was assessed in lungs and kidneys using six non-ventilated animals with no fluid therapy.

Results: In lungs, the liberal group showed increased transpulmonary plateau pressure compared with the restrictive group (liberal, 23.5 ± 2.9 cmH₂O; restrictive, 18.8 ± 2.3 cmH₂O, p = 0.046) under PEEP = 9 cmH₂O. Gene expression associated with inflammation (interleukin [IL]-6) was higher in the liberal-PEEP9 group than the liberal-PEEP3 group (p = 0.006) and restrictive-PEEP9 (p = 0.012), Regardless of the fluid strategy, lung mechanical power and the heterogeneity index were higher, whereas birefringence for claudin-4 and zonula-ocludens-1 gene expression were lower in the PEEP9 groups. Perivascular edema was higher in liberal groups, regardless of PEEP levels. Markers related to damage to epithelial cells [club cell secreted protein (CC16)] and the extracellular matrix (syndecan) were higher in the liberal-PEEP9 group than the liberal-PEEP3 group (p = 0.010 and p = 0.024, respectively). In kidneys, the expression of IL-6 and neutrophil gelatinase-associated lipocalin was higher in PEEP9 groups, regardless of the fluid strategy. For the liberal strategy, PEEP = 9 cmH₂O compared with PEEP = 3 cmH₂O reduced the right ventricle systolic volume (37%) and inferior vena cava collapsibility index (45%).

Conclusion: The combination of a liberal fluid strategy and high PEEP led to more lung damage. The application of high PEEP, regardless of the fluid strategy, may also be deleterious to kidneys.

The Impact of Goal-Directed Fluid Therapy on Postoperative Nausea and Vomiting in High-Risk Patients Undergoing Laparoscopic Sleeve Gastrectomy

PURPOSE

Patients with laparoscopic sleeve gastrectomy (LSG) are at high risk of postoperative nausea and vomiting (PONV). Goal-directed fluid therapy (GDFT) has been proven effective in improving postoperative gastrointestinal function in patients with obesity, but its effect on prevention of PONV remains controversial. This study aimed to investigate the impact of GDFT on PONV in high-risk patients with LSG.

METHODS

In a randomized, single-blinded, two-arm trial, patients with an Apfel score ≥ 3 and scheduled for LSG were included. Patients in the GDFT group received stroke volume-guided fluid therapy. Patients in the control group received conventional fluid therapy. The primary outcome was the incidence of PONV within 48 h after LSG. The second outcome included intensity of PONV, use of rescue therapy, recovery of gastrointestinal function, and postoperative length of stay (LOS).

RESULTS

A total of 137 patients were analyzed. The incidence of PONV in the GDFT group was lower than that in the control group (47.1% vs. 71.6%; odds ratio [95%CI], 0.35 [0.17-0.72]; P = 0.004). Fewer patients in the GDFT group received rescue therapy (30% vs. 58.2%; P = 0.001). Patients following GDFT protocol had a faster return of flatus (27.5 (19, 31) vs. 31 (20, 48) hours, P = 0.037) and shorter postoperative LOS (6.1 ± 1.0 vs. 6.6 ± 1.1 days; P = 0.007).

CONCLUSION

GDFT is conducive to deceasing PONV occurrence, restoring intestinal function, and shortening postoperative LOS in high-risk patients undergoing LSG.

Effects of different fluid management on lung and kidney during pressure-controlled and pressure-support ventilation in experimental acute lung injury

Optimal fluid management is critical during mechanical ventilation to mitigate lung damage. Under normovolemia and protective ventilation, pulmonary tensile stress during pressure-support ventilation (PSV) results in comparable lung protection to compressive stress during pressure-controlled ventilation (PCV) in experimental acute lung injury (ALI). It is not yet known whether tensile stress can lead to comparable protection to compressive stress in ALI under a liberal fluid strategy (LF). A conservative fluid strategy (CF) was compared with LF during PSV and PCV on lungs and kidneys in an established model of ALI. Twenty-eight male Wistar rats received endotoxin intratracheally. After 24 h, they were treated with CF (minimum volume of Ringer's lactate to maintain normovolemia and mean arterial pressure ≥70 mmHg) or LF (~4 times higher than CF) combined with PSV or PCV (VT  = 6 ml/kg, PEEP = 3 cmH2 O) for 1 h. Nonventilated animals (n = 4) were used for molecular biology analyses. CF-PSV compared with LF-PSV: (1) decreased the diffuse alveolar damage score (10 [7.8-12] vs. 25 [23-31.5], p = 0.006), mainly due to edema in axial and alveolar parenchyma; (2) increased birefringence for occludin and claudin-4 in lung tissue and expression of zonula-occludens-1 and metalloproteinase-9 in lung. LF compared with CF reduced neutrophil gelatinase-associated lipocalin and interleukin-6 expression in the kidneys in PSV and PCV. In conclusion, CF compared with LF combined with PSV yielded less lung epithelial cell damage in the current model of ALI. However, LF compared with CF resulted in less kidney injury markers, regardless of the ventilatory strategy.

The Impact of Perioperative Fluid Balance on Postoperative Complications after Esophagectomy for Esophageal Cancer

Background: Perioperative fluid balance is an important indicator in the management of esophageal cancer patients who undergo esophagectomy. However, the association between perioperative fluid balance and postoperative complications after minimally invasive esophagectomy (MIE) remains unclear. Methods: This study included 115 patients with thoracic esophageal squamous cell cancer who underwent MIE between January 2018 and January 2020. We retrospectively evaluated the association between perioperative fluid balance from during surgery to postoperative day (POD) 2, and postoperative complications. Results: The patients were divided into lower group and higher group based on the median fluid balance during surgery and at POD 1 and POD 2. We found that the higher group at POD 1 (≥3000 mL) was the most important indicator of postoperative complications, such as acute pneumonia within 7 days after surgery, and anastomotic leakage (p = 0.029, p = 0.024, respectively). Moreover, the higher group at POD 1 was a significant independent factor for acute postoperative pneumonia by multivariate analysis (OR: 3.270, 95% CI: 1.077–9.929, p = 0.037). Conclusion: This study showed that fluid overload at POD 1 had a negative influence on postoperative complications in patients with esophageal cancer. The fluid balance must be strictly controlled during the early postoperative management of patients undergoing esophageal cancer surgery.

Goal-Directed Fluid Therapy Enhances Gastrointestinal Recovery after Laparoscopic Surgery: A Systematic Review and Meta-Analysis

(1) Background: Whether goal-directed fluid therapy (GDFT) provides any outcome benefit as compared to non-goal-directed fluid therapy (N-GDFT) in elective abdominal laparoscopic surgery has not been determined yet. (2) Methods: A systematic literature search was conducted in MEDLINE, Embase, CENTRAL, Web of Science, and Scopus. The main outcomes were length of hospital stay (LOHS), time to first flatus and stool, intraoperative fluid and vasopressor requirements, serum lactate levels, and urinary output. Pooled risks ratios (RRs) with 95% confidence intervals (CI) were calculated for dichotomous outcomes and weighted mean difference (WMD) with 95% CI for continuous outcomes. (3) Results: Eleven studies were included in the quantitative, and fifteen in the qualitative synthesis. LOHS (WMD: -1.18 days, 95% CI: -1.84 to -0.53) and time to first stool (WMD: -9.8 h; CI -12.7 to -7.0) were significantly shorter in the GDFT group. GDFT resulted in significantly less intraoperative fluid administration (WMD: -441 mL, 95% CI: -790 to -92) and lower lactate levels at the end of the operation: WMD: -0.25 mmol L-1; 95% CI: -0.36 to -0.14. (4) Conclusions: GDFT resulted in enhanced recovery of the gastrointestinal function and shorter LOHS as compared to N-GDFT.

Postoperative ileus-An ongoing conundrum

BACKGROUND

Postoperative ileus is common and is a major clinical problem. It has been widely studied in patients and in experimental models in laboratory animals. A wide variety of treatments have been tested to prevent or modify the course of this disorder.

PURPOSE

This review draws together information on animal studies of ileus with studies on human patients. It summarizes some of the conceptual advances made in understanding the mechanisms that underlie paralytic ileus. The treatments that have been tested in human subjects (both pharmacological and non-pharmacological) and their efficacy are summarized and graded consistent with current clinical guidelines. The review is not intended to provide a comprehensive overview of ileus, but rather a general understanding of the major clinical problems associated with it, how animal models have been useful to elucidate key mechanisms and, finally, some perspectives from both scientists and clinicians as to how we may move forward with this debilitating yet common condition.

Analysis of intraoperative modifiable factors to prevent acute kidney injury after elective noncardiac surgery: intraoperative hypotension and crystalloid administration related to acute kidney injury

Background

The optimal intraoperative blood pressure range and crystalloid administration protocol for the prevention of acute kidney injury (AKI) after elective noncardiac surgery remain unknown.

Methods

This single-center retrospective cohort study included 6296 patients aged ≥ 50 years who had undergone elective noncardiac surgery under general anesthesia. We evaluated the relationship between duration of intraoperative hypotension and AKI. To assess whether the effects of crystalloid administration differed according to baseline estimated glomerular filtration rate (eGFR), we examined the interaction between intraoperative crystalloid administration and eGFR. We calculated univariable and multivariable adjusted odds ratios (ORs) and their 95% confidence intervals (95% CIs) for the prevalence of AKI.

Results

AKI occurred in 431 (6.8%) patients and was associated with intraoperative hypotension. Effects of intraoperative crystalloid administration differed significantly according to baseline eGFR. Increased risk of AKI was noted in patients with eGFR ≤45 ml min⁻¹ 1.73m⁻² who were managed with restrictive or liberal crystalloid administration [OR 4.79 (95% CI 3.10 to 7.32) and 6.43 (95% CI 2.23 to 16.03), respectively] as opposed to those with eGFR >45 ml min⁻¹ 1.73m⁻² who were managed with moderately restrictive crystalloid administration.

Conclusions

Our findings suggest that anesthesiologists should avoid intraoperative hypotension as well as either restrictive or liberal (as opposed to moderately restrictive) crystalloid administration in patients with decreased eGFR. Intraoperative blood pressure and crystalloid administration protocol are major modifiable factors that must be optimized to prevent postoperative AKI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40981-021-00429-9.

[Perioperative fluid management in major abdominal surgery]

Intravascular fluid administration belongs to the cornerstones of perioperative treatment with a substantial impact on surgical outcome especially with respect to major abdominal surgery. By avoidance of hypovolemia and hypervolemia, adequate perioperative fluid management significantly contributes to the reduction of insufficient tissue perfusion as a determinant of postoperative morbidity and mortality. The effective use of intravascular fluids requires detailed knowledge of the substances as well as measures to guide fluid therapy. Fluid management already starts preoperatively and should be continued in the postoperative setting (recovery room, peripheral ward) considering a patient-adjusted and surgery-adjusted hemodynamic monitoring. Communication between all team members participating in perioperative care is essential to optimize fluid management.

Effect of the Type of Intraoperative Restrictive Fluid Management on the Outcome of Pancreaticoduodenectomy: A Systematic Review and Meta-Analysis

Background. The perioperative management of pancreaticoduodenectomy is complicated, and the significant morbidity and mortality may be influenced by the method of intraoperative fluid management. Whether intraoperative restrictive fluid therapy can affect the outcomes of pancreaticoduodenectomy or not is controversial. Methods. PubMed, EMBASE, Cochrane Library, and clinicaltrials.gov were searched for prospective and retrospective studies comparing restrictive and liberal intraoperative fluids in patients undergoing pancreaticoduodenectomy. Following study identification, a systematic review and meta-analysis were performed. Results. Fourteen studies, including six prospective trials and eight retrospective studies, involving 2,596 patients, were included. Intraoperative restrictive fluid regimens had no effect on the mortality compared to liberal fluid regimens in the overall cohort (odds ratio [OR]: 1.39; 95% confidence interval [CI]: 0.82–2.35, $p=0.773$ ). Liberal fluid regimens could increase the risk of pulmonary adverse events (OR: 1.66; 95% CI: 1.10–2.50, $p=0.131$ ) and prolong the length of hospital stay (SMD -0.10; 95% CI -0.19– -0.01, $p=0.375$ ). There were no significant differences in the incidence of pancreatic fistulas. Conclusions. Restrictive fluid regimens have a slight effect on the outcomes of pancreaticoduodenectomy. The clinical relevance of this finding needs to be interpreted. The existing evidence may not be adequate; therefore, further studies are warranted.

Goal-directed hemodynamic therapy versus restrictive normovolemic therapy in major open abdominal surgery: A randomized controlled trial

BACKGROUND

The aim of this study was to compare the occurrence of postoperative complications in patients undergoing elective open abdominal surgery and receiving intraoperative goal-directed hemodynamic therapy or restrictive normovolemic therapy.

METHODS

A total of 401 patients were randomized in the goal-directed hemodynamic therapy or restrictive normovolemic therapy groups. A cardiac output monitor was used in all goal-directed hemodynamic therapy patients and was left at the discretion of anesthetists in charge of patients in the restrictive normovolemic therapy group. The primary outcome was a composite morbidity endpoint (30-day mortality and complications grade 2-4 according to Dindo-Clavien classification). Secondary outcomes were the hospital duration of stay, the incidence of pulmonary, cardiovascular, and renal complications up to 30 days after surgery, and midterm survival.

RESULTS

Intraoperatively, the goal-directed hemodynamic therapy group received higher intravenous fluid volumes (mean of 10.8 mL/kg/h and standard deviation of 4.0) compared with the restrictive normovolemic therapy group (mean of 7.2 mL/kg/h and standard deviation of 2.0; P < .001). On the first postoperative day, similar fluid volumes were infused in the 2 groups. The primary outcome occurred in 57.7% of goal-directed hemodynamic therapy and 53.0% of restrictive normovolemic therapy (relative risk, 1.09 [95% confidence interval, 0.91-1.30]), and there was no significant difference between groups for any secondary outcomes.

CONCLUSION

Among patients undergoing major open abdominal surgery, the goal-directed hemodynamic therapy and the restrictive normovolemic therapy were associated with similar incidence of moderate-to-severe postoperative complications and hospital resource use.

Perioperative Fluid Restriction in Abdominal Surgery: A Systematic Review and Meta-analysis

BACKGROUND

Perioperative fluid management is a critical component in patients undergoing abdominal surgery. However, the benefit of restricted fluid regimen remains inconclusive. This systematic review aimed to explore potential factors causing these inconsistent findings.

METHODS

The literature searches were performed in three databases including PubMed, Embase, and the Cochrane library until August 30, 2018. Only randomized, controlled trials comparing the effect of restricted versus liberal regimen in abdominal surgery were included. The primary outcome was total postoperative complications. Subgroup analysis was performed according to between-group weight increase difference (≥ 2 kg and < 2 kg) and fluid intake ratio (≥ 1.8 and < 1.8).

RESULTS

Sixteen studies were finally included in this meta-analysis. The benefit of the restricted regimen in reducing postoperative complication was only significant in the subgroup with high weight increase difference (≥ 2 kg) (RR 0.67, 95% CI 0.57-0.79) and the subgroup with high fluid intake ratio (≥ 1.8) (RR 0.72, 95% CI 0.62-0.82). In the subgroup with low weight increase difference (< 2 kg) or low fluid intake ratio (< 1.8), the effect of the restricted regimen was not significant (RR 0.88, 95% CI 0.51-1.50, and RR 1.18, 95% CI 0.91-1.53, respectively).

CONCLUSIONS

The benefit of the restricted regimen was only significant in the subgroup with high weight increase difference (≥ 2 kg) or high fluid intake ratio (≥ 1.8).

Effect of cumulative fluid balance on acute kidney injury and patient outcomes after orthotopic liver transplantation: A retrospective cohort study

AIM

Acute kidney injury (AKI) is a serious complication following orthotopic liver transplantation (OLT) and it affects long-term patient survival. The aims of this study were to identify the effects of cumulative fluid balance (FB) on early post-OLT AKI and adverse outcomes and to construct a model to predict AKI.

METHODS

We retrospectively analysed 146 adult patients who underwent OLT. AKI severity was classified according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Univariate and multivariate logistic regression analyses were used to evaluate the association between cumulative FB and post-OLT AKI. The Kaplan-Meier method was used to estimate the survival rate.

RESULTS

Within the perioperative period of 72 hours, 50% (66/132) of patients developed AKI, with 36 (54%), 16 (24%) and 14 (21%) patients having AKI stages 1, 2 and 3, respectively. The cumulative FB was the risk factors for post-OLT AKI (odds ratio [OR], 1.011; 95% confidence interval [CI], 1.156~6.001; P = .021). Preoperative albumin was a protective factor for post-OLT AKI (OR, 0.309; 95% CI, 0.140~0.731; P = .007). The AKI group requires renal replacement therapy (RRT) more (15.2% vs 0%, P = .001) and associated with postoperative complications (56% vs 28.8%, P = .003). The complication-free survival was lower in the AKI group ([11.90 vs 18.74] months, χ² = 9.60, P = .002).

CONCLUSION

Cumulative FB within 72 hours is associated with post-OLT AKI and requires RRT. Cumulative FB impacts the long-term complication-free survival of the recipients.

Comparative Analysis of the Collapsibility Index and Distensibility Index of the Inferior Vena Cava Through Echocardiography with Pulse Pressure Variation That Predicts Fluid Responsiveness in Surgical Patients: An Observational Controlled Trial

OBJECTIVE

The objective for the present study was to compare the collapsibility (IcIVC) and distensibility (IdIVC) indices of the inferior vena cava with pulse pressure variation (PPV) and determine the accuracy and cutoff points of IcIVC and IdIVC that best predict response to intravenous fluid therapy in surgical patients.

DESIGN

Observational, prospective, nonblinded, single center.

SETTING

Hospital do Servidor Público Estadual de São Paulo, in São Paulo, Brazil.

PARTICIPANTS

Volunteer surgical patients.

INTERVENTIONS

This prospective study evaluated adult surgical patients before and after they underwent mechanical ventilation. IcIVC and IdIVC measurements were obtained with echocardiography and PPV through arterial catheterization.

MEASUREMENTS AND MAIN RESULTS

Twenty-two patients with a mean age of 55.7 ± 10.9 years were included; 31.8% of the study participants had PPV values >13% and were shown to be responsive to fluid. A good correlation was detected between PPV and icIVC (R² = 0.71; p < 0.001) and between PPV and idIVC (R² = 0.79; p < 0.001). The area under the receiver operating characteristic curve was 0.98 for icIVC (95% confidence interval 0.81-0.99; p < 0.001) and 0.88 for idIVC (95% confidence interval 0.67-0.98; p < 0.001).

CONCLUSIONS

PPV was found to have good correlation with the inferior vena cava diameter variation using echocardiography in surgical patients undergoing spontaneous and artificial ventilation. The cutoff values that best predicted PPV >13% were >40% for icIVC and >17.6% for idIVC.

Perioperative restrictive versus goal-directed fluid therapy for adults undergoing major non-cardiac surgery

BACKGROUND

Perioperative fluid management is a crucial element of perioperative care and has been studied extensively recently; however, 'the right amount' remains uncertain. One concept in perioperative fluid handling is goal-directed fluid therapy (GDFT), wherein fluid administration targets various continuously measured haemodynamic variables with the aim of optimizing oxygen delivery. Another recently raised concept is that perioperative restrictive fluid therapy (RFT) may be beneficial and at least as effective as GDFT, with lower cost and less resource utilization.

OBJECTIVES

To investigate whether RFT may be more beneficial than GDFT for adults undergoing major non-cardiac surgery.

SEARCH METHODS

We searched the following electronic databases on 11 October 2019: Cochrane Central Register of Controlled Trials, in the Cochrane Libary; MEDLINE; and Embase. Additionally, we performed a targeted search in Google Scholar and searched trial registries (World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov) for ongoing and unpublished trials. We scanned the reference lists and citations of included trials and any relevant systematic reviews identified.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing perioperative RFT versus GDFT for adults (aged ≥ 18 years) undergoing major non-cardiac surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened references for eligibility, extracted data, and assessed risk of bias. We resolved discrepancies by discussion and consulted a third review author if necessary. When necessary, we contacted trial authors to request additional information. We presented pooled estimates for dichotomous outcomes as risk ratios (RRs) with 95% confidence intervals (CIs), and for continuous outcomes as mean differences (MDs) with standard deviations (SDs). We used Review Manager 5 software to perform the meta-analyses. We used a fixed-effect model if we considered heterogeneity as not important; otherwise, we used a random-effects model. We used Poisson regression models to compare the average number of complications per person.

MAIN RESULTS

From 6396 citations, we included six studies with a total of 562 participants. Five studies were performed in participants undergoing abdominal surgery (including one study in participants undergoing cytoreductive abdominal surgery with hyperthermic intraperitoneal chemotherapy (HIPEC)), and one study was performed in participants undergoing orthopaedic surgery. In all studies, surgeries were elective. In five studies, crystalloids were used for basal infusion and colloids for boluses, and in one study, colloid was used for both basal infusion and boluses. Five studies reported the ASA (American Society of Anesthesiologists) status of participants. Most participants were ASA II (60.4%), 22.7% were ASA I, and only 16.9% were ASA III. No study participants were ASA IV. For the GDFT group, oesophageal doppler monitoring was used in three studies, uncalibrated invasive arterial pressure analysis systems in two studies, and a non-invasive arterial pressure monitoring system in one study. In all studies, GDFT optimization was conducted only intraoperatively. Only one study was at low risk of bias in all domains. The other five studies were at unclear or high risk of bias in one to three domains. RFT may have no effect on the rate of major complications compared to GDFT, but the evidence is very uncertain (RR 1.61, 95% CI 0.78 to 3.34; 484 participants; 5 studies; very low-certainty evidence). RFT may increase the risk of all-cause mortality compared to GDFT, but the evidence on this is also very uncertain (RD 0.03, 95% CI 0.00 to 0.06; 544 participants; 6 studies; very low-certainty evidence). In a post-hoc analysis using a Peto odds ratio (OR) or a Poisson regression model, the odds of all-cause mortality were 4.81 times greater with the use of RFT compared to GDFT, but the evidence again is very uncertain (Peto OR 4.81, 95% CI 1.38 to 16.84; 544 participants; 6 studies; very low-certainty evidence). Nevertheless, sensitivity analysis shows that exclusion of a study in which the final volume of fluid received intraoperatively was higher in the RFT group than in the GDFT group revealed no differences in mortality. Based on analysis of secondary outcomes, such as length of hospital stay (464 participants; 5 studies; very low-certainty evidence), surgery-related complications (364 participants; 4 studies; very low-certainty evidence), non-surgery-related complications (74 participants; 1 study; very low-certainty evidence), renal failure (410 participants; 4 studies; very low-certainty evidence), and quality of surgical recovery (74 participants; 1 study; very low-certainty evidence), GDFT may have no effect on the risk of these outcomes compared to RFT, but the evidence is very uncertain. Included studies provided no data on administration of vasopressors or inotropes to correct haemodynamic instability nor on cost of treatment.

AUTHORS' CONCLUSIONS

Based on very low-certainty evidence, we are uncertain whether RFT is inferior to GDFT in selected populations of adults undergoing major non-cardiac surgery. The evidence is based mainly on data from studies on abdominal surgery in a low-risk population. The evidence does not address higher-risk populations or other surgery types. Larger, higher-quality RCTs including a wider spectrum of surgery types and a wider spectrum of patient groups, including high-risk populations, are needed to determine effects of the intervention.

Implementation of an Enhanced Recovery After Surgery (ERAS) Program is Associated with Improved Outcomes in Patients Undergoing Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

BACKGROUND

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has been associated with increased postoperative complications and a prolonged length of stay (LOS). We report on our experience following implementation of an Enhanced Recovery After Surgery (ERAS) program for CRS and HIPEC.

METHODS

Patients were divided into pre- and post-ERAS groups. Modifications in the ERAS group included routine use of transversus abdominis plane blocks, intra- and postoperative fluid restriction, and minimizing the use of narcotics, drains, and nasogastric tubes.

RESULTS

Of a total of 130 procedures, 49 (38%) were in the pre-ERAS group and 81 (62%) were in the ERAS group. Mean LOS was reduced from 10.3 ± 8.9 days to 6.9 ± 5.0 days (p = 0.007) and the rate of grade III/IV complications was reduced from 24 to 15% (p = 0.243) following ERAS implementation. The ERAS group received less intravenous fluid during hospitalization (19.2 ± 18.7 L vs. 32.8 ± 32.5 L, p = 0.003) and used less opioids than the pre-ERAS group (median of 159.7 mg of oral morphine equivalents vs. 272.6 mg). There were no significant changes in the rates of 30-day readmission or acute kidney injury between the two groups (p = non-significant). On multivariable analyses, ERAS was significantly associated with a reduction in LOS (- 2.89 days, 95% CI - 4.84 to - 0.94) and complication rates (odds ratio 0.22, 95% CI 0.08-0.57).

CONCLUSIONS

Implementation of an ERAS program for CRS and HIPEC is associated with a reduction in overall intravenous fluids, postoperative narcotic use, complication rates, and LOS.

Impact of intra-operative fluid and noradrenaline administration on early postoperative renal function after cystectomy and urinary diversion: A retrospective observational cohort study

BACKGROUND

The use of noradrenaline to enable a restrictive approach to intra-operative fluid therapy to avoid salt and water overload has gained increasing acceptance. However, concerns have been raised about the impact of this approach on renal function.

OBJECTIVES

To identify risk factors for acute kidney injury (AKI) in patients undergoing cystectomy with urinary diversion and determine whether administration of noradrenaline and intra-operative hydration regimens affect early postoperative renal function.

DESIGN

Retrospective observational cohort study.

SETTING

University hospital, from 2007 to 2016.

PATIENTS

A total of 769 consecutive patients scheduled for cystectomy and urinary diversion. Those with incomplete data and having pre-operative haemodialysis were excluded.

MAIN OUTCOME MEASURES

AKI was defined as a serum creatinine increase of more than 50% over 72 postoperative hours. Multiple logistic regression analysis was performed to model the association between risk factors and AKI.

RESULTS

Postoperative AKI was diagnosed in 86/769 patients (11.1%). Independent predictors for AKI were the amount of crystalloid administered (odds ratio (OR) 0.79 [95% confidence interval (CI), 0.68 to 0.91], P = 0.002), antihypertensive medication (OR 2.07 [95% CI, 1.25 to 3.43], P = 0.005), pre-operative haemoglobin value (OR 1.02 [95% CI, 1.01 to 1.03], P = 0.010), duration of surgery (OR 1.01 [95% CI, 1.00 to 1.01], P = 0.002), age (OR 1.32 [95% CI, 1.44 to 1.79], P = 0.002) but not the administration of noradrenaline (OR 1.09 [95% CI, 0.94 to 1.21], P = 0.097). Postoperative AKI was associated with longer hospital stay (18 [15 to 22] vs. 16 [15 to 19] days; P = 0.035) and a higher 90-day major postoperative complication rate (41.9 vs. 27.5%; P = 0.002).

CONCLUSION

Noradrenaline administration did not increase the risk for AKI. A too restrictive approach to administration of crystalloids was associated with an increased risk for AKI, particularly in older patients, those receiving antihypertensive medication, and those whose surgery was prolonged. As AKI was associated with longer hospital stay and increased postoperative morbidity, these observations should be taken into account to improve outcome when addressing peri-operative fluid management.

TRIAL REGISTRATION

Not applicable.

Restricting Intraoperative Fluid Volume Allows Earlier Return of Bowel Function After Colon and Rectal Surgery

BACKGROUND

Return of bowel function (ROBF) after abdominal surgery is an important determinant of patient outcomes. The role of intraoperative fluids (IOFs) in colon surgery remains unclear. The aim of this study was to assess the impact of IOF on ROBF in patients undergoing colon surgery. We hypothesized that minimizing IOFs allows earlier ROBF.

METHODS

A 2-year (2016-2017) retrospective analysis of all patients undergoing elective colon resection was performed at our tertiary hospital using a protocol limiting IOF and postoperative narcotics. Patients were divided into two groups: preprotocol (2016) and postprotocol (PoP) (2017). Patients were matched using propensity score matching for age, gender, comorbidities, Anesthesiology Severity Score, indication for procedure, and procedure type. The outcome measured was ROBF. Secondary outcome measures were complication rates and hospital length of stay.

RESULTS

A total of 360 patients were analyzed. After propensity matching, 90 patients (preprotocol: 45; PoP: 45) were included. The mean age was 62.2 ± 14.8 y, 43.3% male, and 44.4% of procedures were performed laparoscopically. There was no difference in demographics and comorbidities between groups. PoP patients received lower IOF (P = 0.036, 2016: 1198.8 ± 1096.5 mL, 2017: 2176.7 ± 1458.3 mL) and lower postoperative narcotics (P = 0.042). PoP patients had earlier ROBF 2[2-4], 4[3-5] (odds ratio: 1.18 [1.05-1.52], P = 0.04), shorter length of stay 3[2-5] d versus 5[4-7] (odds ratio: 1.11 [1.09-1.89], P = 0.043), and trended toward lower complication rates (P = 0.09).

CONCLUSIONS

IOF volume independently impacts ROBF after colon surgery. Restricting IOF allows for earlier bowel function and shorter hospital stay. Further studies defining optimum fluid management impacting ROBF may help optimize patient care.

Clinical guidelines for perioperative hemodynamic management of non cardiac surgical adult patients

Perioperative hemodynamic management, through monitoring and intervention on physiological parameters to improve cardiac output and oxygen delivery (goal-directed therapy, GDT), may improve outcome. However, an Italian survey has revealed that hemodynamic protocols are applied by only 29.1% of anesthesiologists. Aim of this paper is to provide clinical guidelines for a rationale use of perioperative hemodynamic management in non cardiac surgical adult patients, oriented for Italy and updated with most recent studies. Guidelines were elaborated according to NICE (National Institute for Health and Care Excellence) and GRADE system (Grading of Recommendations of Assessment Development and Evaluations). Key questions were formulated according to PICO system (Population, Intervention, Comparators, Outcome). Guidelines and systematic reviews were identified on main research databases and strategy was updated to June 2018. There is not enough good quality evidence to support the adoption of a GDT protocol in order to reduce mortality, although it may be useful in high risk patients. Perioperative GDT protocol to guide fluid therapy is recommended to reduce morbidity. Continuous monitoring of arterial pressure may help to identify short periods of hemodynamic instability and hypotension. Fluid strategy should aim to a near zero balance in normovolemic patients at the beginning of surgery, and a slight positive fluid balance may be allowed to protect renal function. Drugs such as inotropes, vasocostrictors, and vasodilatator should be used only when fluids alone are not sufficient to optimize hemodynamics. Perioperative GDT protocols are associated with a reduction in costs, although no economic study has been performed in Italy.

Restrictive Versus Liberal Fluid Regimens in Patients Undergoing Pancreaticoduodenectomy: a Systematic Review and Meta-Analysis

BACKGROUND

Pancreaticoduodenectomy is associated with significant morbidity and mortality which may be influenced by perioperative fluid management. It remains unclear whether liberal and restrictive fluid regimens impact mortality and morbidity in patients undergoing pancreaticoduodenectomy.

METHODS

Medline, EMBASE, Cochrane Library and clinicaltrials.gov were searched for studies comparing restrictive and liberal perioperative fluids in patients undergoing pancreaticoduodenectomy. Both prospective and retrospective studies in those undergoing pancreaticoduodenectomy were eligible for inclusion where the patient outcomes were stratified to restrictive and liberal perioperative fluid management regimens, with mortality as the primary outcome. Following study identification, a systematic review and meta-analysis with trial sequential analysis was completed.

RESULTS

Thirteen studies including five prospective trials and eight retrospective analyses totalling 3062 patients were included. Restrictive fluid regimens were associated with a significant reduction in mortality compared to liberal fluid regimens for the overall cohort (odds ratio 0.54; 95% CI 0.31-0.94, p = 0.03). There were no significant differences in complication profile. Subgroup analysis revealed this result was contributed to significantly by retrospective studies. The results of the trial sequential analysis suggest this mortality benefit may be due to a type I statistical error and that further patient numbers are required for definitive conclusions.

CONCLUSIONS

Restrictive fluid regimens are associated with a reduction in mortality following pancreaticoduodenectomy. The clinical relevance of this finding needs to be interpreted pragmatically given the lack of association with significant causes of morbidity and in considering the results of the recently published RELIEF study.

Albumin infusion rate and plasma volume expansion: a randomized clinical trial in postoperative patients after major surgery

Background

Optimal infusion rate of colloids in patients with suspected hypovolemia is unknown, and the primary objective of the present study was to test if plasma volume expansion by 5% albumin is greater if fluid is administered slowly rather than rapidly.

Methods

Patients with signs of hypoperfusion after major abdominal surgery were randomized to intravenous infusion of 5% albumin at a dose of 10 ml/kg (ideal body weight) either rapidly (30 min) or slowly (180 min). Plasma volume was measured using radiolabeled albumin at baseline, at 30 min, and at 180 min after the start of infusion. Primary outcome was change in plasma volume from the start of infusion to 180 min after the start of infusion. Secondary outcomes included the change in the area under the plasma volume curve and transcapillary escape rate (TER) for albumin from 180 to 240 min after the start of albumin infusion.

Results

A total of 33 and 31 patients were included in the analysis in the slow and rapid groups, respectively. The change in plasma volume from the start of infusion to 180 min did not differ between the slow and rapid infusion groups (7.4 ± 2.6 vs. 6.5 ± 4.1 ml/kg; absolute difference, 0.9 ml/kg [95%CI, − 0.8 to 2.6], P = 0.301). Change in the area under the plasma volume curve was smaller in the slow than in the rapid infusion group and was 866 ± 341 and 1226 ± 419 min ml/kg, respectively, P < 0.001. TER for albumin did not differ and was 5.3 ± 3.1%/h and 5.4 ± 3%/h in the slow and in the rapid infusion groups, respectively, P = 0.931.

Conclusions

This study does not support our hypothesis that a slow infusion of colloid results in a greater plasma volume expansion than a rapid infusion. Instead, our result of a smaller change in the area under the plasma volume curve indicates that a slow infusion results in a less efficient plasma volume expansion, but further studies are required to confirm this finding. A rapid infusion has no effect on vascular leak as measured after completion of the infusion.

Trial registration

EudraCT2013-004446-42 registered December 23, 2014.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2477-7) contains supplementary material, which is available to authorized users.

Effect of Intraoperative Goal-directed Balanced Crystalloid versus Colloid Administration on Major Postoperative Morbidity

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

Crystalloid solutions leave the circulation quickly, whereas colloids remain for hours, thus promoting hemodynamic stability. However, colloids are expensive and promote renal toxicity in critical care patients. This study tested the hypothesis that goal-directed colloid administration during elective abdominal surgery decreases 30-day major complications more than goal-directed crystalloid administration.

Methods

In this parallel-arm double-blinded multicenter randomized trial, adults having moderate- to high-risk open and laparoscopically assisted abdominal surgery with general anesthesia were randomly assigned to Doppler-guided intraoperative volume replacement with 6% hydroxyethyl starch 130/0.4 (n = 523) or lactated Ringer’s solution (n = 534). The primary outcome was a composite of serious postoperative cardiac, pulmonary, infectious, gastrointestinal, renal, and coagulation complications that were assessed with a generalized estimating equation multivariate model. The primary safety outcome was a change in serum creatinine concentration up to 6 months postoperatively, compared to baseline concentrations.

Results

A total of 1,057 patients were included in the analysis. Patients assigned to crystalloid received a median [quartile 1, quartile 3] amount of 3.2 l [2.3, 4.4] of crystalloid, and patients assigned to colloid received 1.0 l [0.5, 1.5] of colloid and 1.8 l [1.2, 2.4] of crystalloid. The estimated intention-to-treat common effect relative risk for the primary composite was 0.90 for colloids versus crystalloids (95% CI: 0.65 to 1.23, P = 0.51), and 18% (91 of 523) of colloid patients and 20% (103 of 534) of crystalloid patients incurred at least one component of the primary outcome composite. There was no evidence of renal toxicity at any time.

Conclusions

Doppler-guided intraoperative hydroxyethyl starch administration did not significantly reduce a composite of serious complications. However, there was also no indication of renal or other toxicity.

Thresholds for optimal fluid administration and weight gain after laparoscopic colorectal surgery

Background

Perioperative fluid overload is an important modifiable risk factor for adverse outcomes after colorectal surgery. This study aimed to define critical thresholds for perioperative fluid management and postoperative weight gain for patients undergoing elective laparoscopic colorectal surgery.

Methods

This was an analysis of consecutive elective laparoscopic colorectal resections at Lausanne University Hospital from May 2011 to May 2017. Main outcomes were overall, major (Clavien–Dindo grade IIIb or above) and respiratory complications, and postoperative ileus. Thresholds regarding perioperative fluid management and postoperative weight gain were identified through receiver operating characteristic (ROC) analysis and clinical judgement. Independent risk factors for all four outcomes were assessed by multinominal logistic regression.

Results

Overall and major complications occurred in 210 (36·2 per cent) and 46 (7·9 per cent) of 580 patients respectively. Twenty‐three patients (4·0 per cent) had respiratory complications and 98 (16·9 per cent) had postoperative ileus. Median length of hospital stay was 5 (i.q.r. 3–9) days. Based on respiratory complications, thresholds for perioperative intravenous fluid administration (postoperative day (POD) 0) were set pragmatically at 3000 ml for colonic (calculated threshold 3120 ml (area under ROC curve (AUROC) 0·63)) and 4000 ml for rectal (AUROC 0·79) procedures. Postoperative weight gain of 2·5 kg at POD 2 was predictive of respiratory complications. Multivariable analysis retained perioperative intravenous fluid administration over the above thresholds as an independent risk factor for overall (odds ratio (OR) 2·25, 95 per cent c.i. 1·23 to 4·11), major (OR 2·49, 1·17 to 5·31) and respiratory (OR 4·71, 1·42 to 15·58) complications. Weight gain above 2·5 kg at POD 2 was identified as a risk factor for respiratory complications (OR 3·58, 1·10 to 11·70) and ileus (OR 1·82, 1·02 to 3·52).

Conclusion

Perioperative intravenous fluid and weight thresholds were associated with postoperative adverse outcomes. These thresholds need independent validation.

Enhanced recovery after elective surgery for lung cancer patients: analysis of current pathways and perspectives

The concept of enhanced recovery after surgery (ERAS), initially introduced in the field of colorectal surgery, has been developed in order to optimize the postoperative course. In recent years the number of authors analyzing the role of ERAS in lung cancer surgery is increasing, highlighting several interventions with positive effects on the postoperative course. Yet it is still difficult to draw definite conclusions and specific guidelines, as most of these studies largely differ for their methodological aspects and study populations. Herein we focus on the key elements of each single intervention, trying to identify what we can apply in a common pathway, and which aspects are still to be evaluated for the validation of an ERAS program.

Perioperative Fluid Management in the Enhanced Recovery after Surgery (ERAS) Pathway

Fluid management is an essential component of the Enhanced Recovery after Surgery (ERAS) pathway. Optimal management begins in the preoperative period and continues through the intraoperative and postoperative phases. In this review, we outline current evidence-based practices for fluid management through each phase of the perioperative period. Preoperatively, patients should be encouraged to hydrate until 2 hours prior to the induction of anesthesia with a carbohydrate-containing clear liquid. When mechanical bowel preparation is necessary, with modern isoosmotic solutions, fluid repletion is not necessary. Intraoperatively, fluid therapy should aim to maintain euvolemia with an individualized approach. While some patients may benefit from goal-directed fluid therapy, a restrictive, zero-balance approach to intraoperative fluid management may be reasonable. Postoperatively, early initiation of oral intake and cessation of intravenous therapy are recommended.

Goal-directed fluid therapy in urgent GAstrointestinal Surgery-study protocol for A Randomised multicentre Trial: The GAS-ART trial

INTRODUCTION

Intravenous fluid therapy during gastrointestinal surgery is a life-saving part of the perioperative care. Too little fluid may lead to hypovolaemia, decreased organ perfusion and circulatory shock. Excessive fluid administration increases postoperative complications, worsens pulmonary and cardiac function as well as the healing of surgical wounds. Intraoperative individualised goal-directed fluid therapy (GDT) and zero-balance therapy (weight adjusted) has shown to reduce postoperative complications in elective surgery, but studies in urgent gastrointestinal surgery are sparse. The aim of the trial is to test whether zero-balance GDT reduces postoperative mortality and major complications following urgent surgery for obstructive bowel disease or perforation of the gastrointestinal tract compared with a protocolled standard of care.

METHODS/ANALYSIS

This study is a multicentre, randomised controlled trial with planned inclusion of 310 patients. The randomisation procedure is stratified by hospital and by obstructive bowel disease and perforation of the gastrointestinal tract. Patients are allocated into either 'the standard group' or 'the zero-balance GDT group'. The latter receive intraoperative GDT (guided by a stroke volume algorithm) and postoperative zero-balance fluid therapy based on body weight and fluid charts. The protocolled treatment continues until free oral intake or the seventh postoperative day.The primary composite outcome is death, unplanned reoperations, life-threatening thromboembolic and bleeding complications, a need for mechanical ventilation or dialysis. Secondary outcomes are additional complications, length of hospital stay, length of stay in the intensive care unit, length of mechanical ventilation, readmissions and time to death. Follow-up is 90 days.We plan intention-to-treat analysis of the primary outcome.

ETHICS AND DISSEMINATION

The Danish Scientific Ethics Committee approved the GAS-ART trial before patient enrolment (J: SJ-436). Enrolment of patients began in August 2015 and is proceeding. We expect to publish the GAS-ART results in Summer 2019.

TRIAL REGISTRATION NUMBER

EudraCT 2015-000563-14.

Systematic Review and Meta-analysis of Restrictive Perioperative Fluid Management in Pancreaticoduodenectomy

BACKGROUND

There is significant interest and controversy surrounding the effect of restrictive fluid management on outcomes in major gastrointestinal surgery. This has been most studied in colorectal surgery, although the literature relating to pancreaticoduodenectomy (PD) patients is growing. The aim of this paper was to generate a comprehensive review of the available evidence for restrictive perioperative fluid management strategies and outcomes in PD.

METHODS

MEDLINE/PubMed, Embase, and the Cochrane Library were searched from inception to April 2017. A review protocol was utilized and registered with PROSPERO. Primary citations that evaluated perioperative fluid management in PD, including those as part of a clinical pathway, were considered. The primary outcome was postoperative pancreatic fistula (POPF). Secondary outcomes included delayed gastric emptying (DGE), complication rate, length of stay (LOS), mortality, and readmission.

RESULTS

A total of six studies involving 846 patients were included (2009-2015), of which four were RCTs. Pooled analysis of RCTs and high-quality observational studies found no effect of restrictive intraoperative fluid management on POPF, DGE, complication rate, LOS, mortality, and readmission. Only one study assessed postoperative fluid management exclusively and found prolonged LOS in patients in the restricted fluid group.

CONCLUSION

Based on results of RCTs and high-quality observational studies, intraoperative fluid restriction in PD has not been shown to significantly affect postoperative outcomes. There are too few studies assessing postoperative fluid management to draw conclusions at this time.

Impact of maintenance, resuscitation and unintended fluid therapy on global fluid load after elective coronary artery bypass surgery

INTRODUCTION

Standardized protocols are provided for maintenance and replacement fluid therapy in critically ill patients. However, unintended fluid sources (analgesics, antibiotics and other drugs) are not always taken into account when prescribing intravenous fluid therapy. We evaluated the extent to which maintenance, resuscitation and unintended fluids contributed to total fluid load in elective coronary artery bypass graft patients during their ICU stay.

METHODS

Data on intravenous and oral fluid input and output were retrospectively collected from the electronic medical files.

RESULTS

Sixty patients were included. Maintenance fluids represented 1435 ± 570mL (49%) and 2214 ± 657mL (71%), resuscitation fluids 847 ± 542mL (29%) and 338 ± 559mL (11%), unintended fluids 639 ± 162mL (22%) and 576 ± 285mL (18%) respectively on day 1 and day 2. Mean oral intake increased almost fourfold (from 258mL to 1017mL) on the second day.

CONCLUSION

Postoperative maintenance and resuscitation fluids are responsible for most of the observed total fluid load on the first two days after elective coronary artery bypass graft surgery. Unintended fluid load is underestimated and has to be taken into account during fluid prescription.

Early Diuresis After Colon and Rectal Surgery Does Not Reduce Length of Hospital Stay: Results of a Randomized Trial

BACKGROUND

Excessive perioperative fluid administration likely increases postoperative cardiovascular, infectious, and GI complications. Early administration of diuretics after elective surgery facilitates rapid mobilization of excess fluid, potentially leading to decreased bowel edema, more rapid return of bowel function, and reduced length of hospital stay.

OBJECTIVE

This study aimed to evaluate the benefit of early diuresis after elective colon and rectal surgery in the setting of an enhanced recovery after surgery practice.

DESIGN

This was a prospective study.

SETTINGS

The study was conducted at a quaternary referral center.

PATIENTS

A randomized, open-label, parallel-group trial was conducted in patients undergoing elective colon and rectal surgery at a single quaternary referral center.

INTERVENTION

The primary intervention was administration of intravenous furosemide plus enhanced recovery after surgery on postoperative day 1 and 2 versus enhanced recovery after surgery alone.

MAIN OUTCOME MEASURES

The primary outcome was length of hospital stay. Secondary outcomes included 30-day readmission rate, time to stool output during hospitalization after surgery, and incidence of various complications within the first 48 hours of hospital stay.

RESULTS

In total, 123 patients were randomly assigned to receive either furosemide plus enhanced recovery after surgery (n = 62) or enhanced recovery after surgery alone (n = 61). Groups were evenly matched at baseline. At interim analysis, length of hospital stay was not superior in the intervention group (80.6 vs 99.6 hours, p = 0.564). No significant difference was identified in the rates of nasogastric tube replacement (1.6% vs 9.7%, p = 0.125). Time to return of bowel function was significantly longer in the intervention group (45.4 vs 48.8 hours, p = 0.048). The decision was made to end the study early because the conditional power of the study favored futility.

LIMITATIONS

This was a single-center study.

CONCLUSIONS

Early administration of furosemide does not significantly reduce the length of hospital stay after elective colon and rectal surgery in the setting of enhanced recovery after surgery practice. See Video Abstract at http://links.lww.com/DCR/A714.

Risk factors for postoperative ileus following elective laparoscopic right colectomy: a retrospective multicentric study

PURPOSE

Postoperative ileus (POI) is associated with an elevated risk of other complications and increases the economic impact on healthcare services. The aim of this study was to identify pre-, intra- and postoperative risk factors associated with the development of POI following elective laparoscopic right colectomy.

METHODS

Between 2004 and 2016, 637 laparoscopic right colectomies were performed. Data were analysed retrospectively thanks to the CLIHMET database. Potential contributing factors were analysed by logistic regression.

RESULTS

Patients with POI (n = 113, 17.7%) were compared to those without postoperative ileus (WPOI) (n = 524, 82.3%). In the POI group, there were more men (62 vs 49%; p = 0.012), more use of epidural anaesthesia (19 vs 9%; p = 0.004), more intraoperative blood transfusion requirements (7 vs 3%; p = 0.018) and greater perioperative intravenous fluid administration (2000 vs 1750 mL; p < 0.001). POIs were more frequent when extracorporeal vascular section (20 vs 12%; p = 0.049) and transversal incision for extraction site (34 vs 23%; p = 0.044) were performed. Overall surgical complications in the POI group were significantly greater than in the control group WPOI (31.9 vs 12.0%; p < 0.0001). Multivariate analysis found the following independent POI risk factors: male gender (HR = 2.316, 1.102-4.866), epidural anaesthesia (HR = 2.958, 1.250-6.988) and postoperative blood transfusion requirement (HR = 6.994, 1.550-31.560).

CONCLUSIONS

This study is one of the first to explore the CLIHMET database and the first to use it for investigating risk factors for POI development. Modifiable risk factors such as epidural anaesthesia and intraoperative blood transfusion should be used with caution in order to decrease POI rates.

Goal-directed fluid therapy versus conventional fluid therapy in colorectal surgery: A meta analysis of randomized controlled trials

OBJECTIVES

This meta-analysis was conducted to compare the effects of goal-directed fluid therapy (GDFT) versus conventional fluid therapy (CFT) in colorectal surgery on patients' postoperative outcome and to detect whether the results differ between studies with the Enhanced Recovery After Surgery (ERAS) protocol and those without, between studies using different devices for GDFT, or between different surgical approaches (laparoscopy or laparotomy).

METHODS

The Cochrane Library, PubMed, Embase, Wanfang Data and ClinicalTrials.com were searched for studies from January,1990 to February, 2018. Randomized controlled trials (RCTs) comparing both two abovementioned fluid therapy protocols in colorectal surgery were included. The primary outcome was 30-day mortality after surgery. Secondary outcomes were length of hospital stay (LOS), complication rate, ICU admission and gastrointestinal indicators.

RESULTS

Eleven studies were included, including a total of 1281 patients: the GDFT group included 624 patients and the control group included 657 patients. No significant differences were found between groups in 30-day mortality (relative risk, RR 0.86,0.28 to 2.63, P = 0.79), LOS (weighted mean difference, WMD 0.22,-0.1 to 0.55, P = 0.18), and ICU admission (RR 0.42, 0.17 to 1.04, P = 0.06). However, the GDFT group had a lower complication rate (RR 0.84,0.71 to 0.99, P = 0.04). In subgroup analyses, time to first flatus and time to tolerate an oral diet were shorter in GDFT group than the control group in studies who did not use the ERAS protocol. No publication bias was identified according to Begg's test.

CONCLUSION

Compared with conventional fluid therapy, GDFT may not improve patients' postoperative outcome in colorectal surgery. However, the improvement of gastrointestinal function associated with GDFT over conventional fluid therapy was significant in the surgeries that did not use the ERAS protocol.

Restrictive versus Liberal Fluid Therapy for Major Abdominal Surgery

BACKGROUND

Guidelines to promote the early recovery of patients undergoing major surgery recommend a restrictive intravenous-fluid strategy for abdominal surgery. However, the supporting evidence is limited, and there is concern about impaired organ perfusion.

METHODS

In a pragmatic, international trial, we randomly assigned 3000 patients who had an increased risk of complications while undergoing major abdominal surgery to receive a restrictive or liberal intravenous-fluid regimen during and up to 24 hours after surgery. The primary outcome was disability-free survival at 1 year. Key secondary outcomes were acute kidney injury at 30 days, renal-replacement therapy at 90 days, and a composite of septic complications, surgical-site infection, or death.

RESULTS

During and up to 24 hours after surgery, 1490 patients in the restrictive fluid group had a median intravenous-fluid intake of 3.7 liters (interquartile range, 2.9 to 4.9), as compared with 6.1 liters (interquartile range, 5.0 to 7.4) in 1493 patients in the liberal fluid group (P<0.001). The rate of disability-free survival at 1 year was 81.9% in the restrictive fluid group and 82.3% in the liberal fluid group (hazard ratio for death or disability, 1.05; 95% confidence interval, 0.88 to 1.24; P=0.61). The rate of acute kidney injury was 8.6% in the restrictive fluid group and 5.0% in the liberal fluid group (P<0.001). The rate of septic complications or death was 21.8% in the restrictive fluid group and 19.8% in the liberal fluid group (P=0.19); rates of surgical-site infection (16.5% vs. 13.6%, P=0.02) and renal-replacement therapy (0.9% vs. 0.3%, P=0.048) were higher in the restrictive fluid group, but the between-group difference was not significant after adjustment for multiple testing.

CONCLUSIONS

Among patients at increased risk for complications during major abdominal surgery, a restrictive fluid regimen was not associated with a higher rate of disability-free survival than a liberal fluid regimen and was associated with a higher rate of acute kidney injury. (Funded by the Australian National Health and Medical Research Council and others; RELIEF ClinicalTrials.gov number, NCT01424150 .).