Effect of perioperative goal-directed hemodynamic therapy on postoperative recovery following major abdominal surgery-a systematic review and meta-analysis of randomized controlled trials

Fluid therapy and pulmonary complications in abdominal surgeries: randomized controlled trial

BACKGROUND

There is no consensus on the most effective strategy for Postoperative Pulmonary Complication (PPC) reduction. This study hypothesized that a Goal-Directed Fluid Therapy (GDFT) protocol of infusion of predetermined boluses reduces the occurrence of PPC in patients undergoing elective open abdominal surgeries when compared with Standard of Care (SOC) strategy.

METHODS

Randomized, prospective, controlled study, conducted from May 2012 to December 2014, with ASA I, II or III patients undergoing open abdominal surgeries, lasting at least 120 min, under general anesthesia, randomized into the SOC and the GDFT group. In the SOC, fluid administration was according to the anesthesiologist's discretion. In the GDFT, the intervention protocol, based on bolus infusion according to blood pressure and delta pulse pressure, was applied. Patients were postoperatively evaluated by an anesthesiologist blinded to the group allocation regarding PPC incidence, mortality, and Length of Hospital Stay (LOHS).

RESULTS

Forty-two patients in the SOC group and 43 in the GDFT group. Nineteen patients (45%) in the SOC and 6 in the GDFT (14%) had at least one PPC (p = 0.003). There was no difference in mortality or LOHS between the groups. Among the patients with PPC, four died (25%), compared to two deaths in patients without PPC (3%) (p = 0.001). The LOHS had a median of 14.5 days in the group with PPC and 9 days in the group without PPC (p = 0.001).

CONCLUSION

The GDFT protocol resulted in a lower rate of PPC; however, the LOHS and mortality did not reduce.

Optimizing Postoperative Clinical Outcomes in Spinal Surgery Through Preoperative Oral Carbohydrate Loading: A Case-control Study

PURPOSE

Preoperative oral carbohydrate loading is a component of enhanced recovery after surgery protocols. The aim of this study is to investigate the effects of preoperative oral carbohydrate loading on postoperative clinical outcomes in spinal surgery patients.

DESIGN

This is a prospective case-control study.

METHODS

This study was conducted with patients who underwent spinal surgery from October 1, 2020 to October 1, 2021 in a neurosurgery clinic of an education and research hospital. The intervention group (n = 46) ingested 800 mL oral carbohydrate drinks at least 8 hours before surgery. The postoperative clinical outcomes were nausea, vomiting, antiemetic and analgesic drug medication, inflammation, and bleeding. The first flatus and defecation time, oral intake time, mobilization time, and length of stay in hospital were assessed postoperatively. Adverse events were monitored up to 24 hours postoperatively. The control group (n = 46) underwent routine fasting protocols.

FINDINGS

Lower rates of vomiting and bleeding during and after surgery and earlier defecation time and first mobilization time were determined in the intervention group, and the difference compared with the control group was statistically significant.

CONCLUSIONS

Preoperative oral carbohydrate loading is a nonpharmacological intervention that has a positive effect on postoperative clinical outcomes in patients who underwent spinal surgery and should be included in the enhanced recovery after surgery protocol.

The effect of goal-directed crystalloid versus colloid administration on postoperative spirometry parameters: a substudy of a randomized controlled clinical trial

BACKGROUND

Pulmonary function is impaired after major abdominal surgery and might be less impaired by restrictive fluid administration. Under the assumption of a fluid-sparing effect of colloids, we tested the hypothesis that an intraoperative colloid-based goal-directed fluid management strategy impairs postoperative pulmonary function parameters less compared to goal-directed crystalloid administration.

METHODS

We performed a preplanned, single-center substudy within a recently published trial evaluating the effect of goal-directed crystalloids versus colloids on a composite of major complications. Sixty patients undergoing major open abdominal surgery were randomized to Doppler-guided intraoperative fluid replacement therapy with lactated Ringer's solution (n = 31) or unbalanced 6% hydroxyethyl starch 130/0.4 (n = 29). A blinded investigator performed bedside spirometry (Spirobank-G, Medical International Research, Rome, Italy) preoperatively as well as 6, 24, and 48 h postoperatively.

RESULTS

Median total intraoperative fluid requirements were significantly higher during crystalloid administration compared to patients receiving colloids (4567 ml vs. 3044 ml, p = 0.01). Six hours after surgery, pulmonary function parameters did not differ significantly between the crystalloid - and the colloid group: forced vital capacity (FVC): 1.6 l (1.2-2 l) vs. 1.9 l (1.5-2.4 l), p = 0.15; forced expiratory volume in 1 second (FEV1): 1.1 l (0.9-1.6 l) vs. 1.4 l (1.2-1.7 l), p = 0.18; and peak expiratory flow (PEF): 2 l.sec-1 (1.5 - 3.6 l.sec -1) vs. 2.3 l.sec -1 (1.8 - 3.4 l.sec -1), p = 0.23. Moreover, postoperative longitudinal time × group interactions of FVC, FEV1, and PEF between 6 and 48 postoperative hours did not differ significantly.

CONCLUSION

Postoperative pulmonary function parameters were similarly impaired in patients receiving goal-directed crystalloid administration as compared to goal-directed colloid administration during open abdominal surgery.

TRIAL REGISTRATION

ClinicalTrials.gov ( NCT00517127 , registered on August 16, 2007) and EudraCT (2005-004602-86).

Application of enhanced recovery after surgery during the perioperative period in children with Meckel's diverticulum-a single-center prospective clinical trial

Background

Enhanced recovery after surgery (ERAS) has been widely used in adult surgery. However, few studies have reported the efficacy of ERAS in paediatric patients with Meckel's diverticulum (MD), the aim of the study was to prospectively evaluate the safety and efficacy of ERAS in treating MD.

Methods

A prospective randomised controlled study of children with MD admitted to our hospital from Jan 1, 2021 to Dec 31, 2023 were conducted, we developed and implemented an ERAS program for this patients. All cases were strictly selected according to the inclusion and exclusion criteria. Among these patients, they were randomly assigned to the ERAS group or the traditional (TRAD) group with random number table row randomization. The main observational indicators were operation time, intraoperative hemorrhage, FLACC pain scale results on 2 h, 6 h, 12 h, 24 h after surgery, length of postoperative stay (LOPS), time to first defecation, time to first eating after surgery, time to discontinuation of intravenous infusion, total treatment cost, incidence of postoperative complications, 30-day readmission rate and parental satisfaction rate.

Results

A total of 50 patients underwent Meckel's diverticulectomy during this period, 7 patients were excluded, 23 patients were assigned to the ERAS group and 20 patients were assigned to the TRAD group. There were no significant differences in demographic data and operation time, intraoperative hemorrhage. The FLACC pain scale results on 2 h, 6 h, 12 h, 24 h after surgery were significantly lower in the ERAS group. The LOPS was 6.17 ± 0.89 days in the ERAS group and 8.30 ± 1.26 days in the TRAD group, resulting in a significantly shorter LOPS in ERAS group. ERAS could also reduce the first postoperative defecation time, the time to first eating after surgery and the time to discontinuation of intravenous infusion. The treatment cost was decreased in the ERAS group. The rate of complications and 30-day readmission were not significantly different between the two groups.

Conclusions

In this single-center study, the ERAS protocol for patients with MD requiring surgery was safe and effective.

Goal-directed fluid therapy using stroke volume variation on length of stay and postoperative gastrointestinal function after major abdominal surgery-a randomized controlled trial

BACKGROUND AND OBJECTIVE

The effectiveness of goal-directed fluid therapy (GDFT) in promoting postoperative recovery remains unclear, the aim of this study was to evaluate the effect of GDFT on length of hospital stay and postoperative recovery of GI function in patients undergoing major abdominal oncologic surgery.

METHODS

In this randomized, double- blinded, controlled trial, adult patients scheduled for elective major abdominal surgery with general anesthesia, were randomly divided into the GDFT protocol (group G) or conventional fluid therapy group (group C). Patients in group C underwent conventional fluid therapy based on mean arterial pressure (MAP) and central venous pressure (CVP) whereas those in group G received GDFT protocol associated with the SVV less than 12% and the cardiac index (CI) was controlled at a minimum of 2.5 L/min/m2. The primary outcomes were the length of hospital stay and postoperative GI function.

RESULTS

One hundred patients completed the study protocol. The length of hospital stay was significantly shorter in group G compared with group C [9.0 ± 5.8 days versus 12.0 ± 4.6 days, P = 0.001]. Postoperative gastrointestinal dysfunction (POGD) occurred in two of 50 patients (4%) in group G and 16 of 50 patients (32%) in the control group (P < 0.001). GDFT significantly also shorten time to first flatus by 11 h (P = 0.009) and time to first tolerate oral diet by 2 days (P < 0.001).

CONCLUSIONS

Guided by SVV and CI, the application of GDFT has the potential to expedite postoperative recovery of GI function and reduce hospitalization duration after major abdominal surgery.

TRIAL REGISTRATION

This study was registered on www.

CLINICALTRIALS

gov on 07/05/2019 with registration number: NCT03940144.

Stroke volume variation and dynamic arterial elastance predict fluid responsiveness even in thoracoscopic esophagectomy: a prospective observational study

PURPOSE

It remains unknown whether stroke volume variation (SVV), pulse pressure variation (PPV), and dynamic arterial elastance (Eadyn) are suitable for monitoring fluid management during thoracoscopic esophagectomy (TE) in the prone position with one-lung ventilation and artificial pneumothorax. Our study aimed to evaluate the accuracy of SVV, PVV, and Eadyn in predicting the fluid responsiveness in these patients.

METHODS

We recruited 24 patients who had undergone TE. Patients with a mean arterial blood pressure ≤ 65 mmHg received a 200-ml bolus of 6% hydroxyethyl starch over 10 min. Fluid responders showed the stroke volume index ≥ 15% 5 min after the fluid bolus. Receiver operating characteristic (ROC) curves were generated and area under the ROC curve (AUROC) was calculated.

RESULTS

We obtained 61 fluid bolus data points, of which 20 were responders and 41 were non-responders. The median SVV before the fluid bolus in responders was significantly higher than that in non-responders (18% [interquartile range (IQR) 13-21] vs. 12% [IQR 8-15], P = 0.001). Eadyn was significantly lower in responders than in non-responders (0.55 [IQR 0.45-0.78] vs. 0.91 [IQR 0.67-1.00], P < 0.001). There was no difference in the PPV between the groups. The AUROC was 0.76 for SVV (95% confidence interval [CI] 0.62-0.89, P = 0.001), 0.56 for PPV (95% CI 0.41-0.71, P = 0.44), and 0.82 for Eadyn (95% CI 0.69-0.95, P < 0.001).

CONCLUSIONS

SVV and Eadyn are reliable parameters for predicting fluid responsiveness in patients undergoing TE.

Artificial Intelligence Applications in Space Medicine

INTRODUCTION:During future interplanetary space missions, a number of health conditions may arise, owing to the hostile environment of space and the myriad of stressors experienced by the crew. When managing these conditions, crews will be required to make accurate, timely clinical decisions at a high level of autonomy, as telecommunication delays and increasing distances restrict real-time support from the ground. On Earth, artificial intelligence (AI) has proven successful in healthcare, augmenting expert clinical decision-making or enhancing medical knowledge where it is lacking. Similarly, deploying AI tools in the context of a space mission could improve crew self-reliance and healthcare delivery.METHODS: We conducted a narrative review to discuss existing AI applications that could improve the prevention, recognition, evaluation, and management of the most mission-critical conditions, including psychological and mental health, acute radiation sickness, surgical emergencies, spaceflight-associated neuro-ocular syndrome, infections, and cardiovascular deconditioning.RESULTS: Some examples of the applications we identified include AI chatbots designed to prevent and mitigate psychological and mental health conditions, automated medical imaging analysis, and closed-loop systems for hemodynamic optimization. We also discuss at length gaps in current technologies, as well as the key challenges and limitations of developing and deploying AI for space medicine to inform future research and innovation. Indeed, shifts in patient cohorts, space-induced physiological changes, limited size and breadth of space biomedical datasets, and changes in disease characteristics may render the models invalid when transferred from ground settings into space.Cheung HC, De Louche C, Komorowski M. Artificial intelligence applications in space medicine. Aerosp Med Hum Perform. 2023; 94(8):610-622.

Frailty: the perioperative and anesthesia challenges of an emerging pandemic

Frailty is a complex and multisystem biological process characterized by reductions in physiological reserve. It is an increasingly common phenomena in the surgical population, and significantly impacts postoperative recovery. In this review, we will discuss the pathophysiology of frailty, as well as preoperative, intraoperative, and postoperative considerations for frailty care. We will also discuss the different models of postoperative care, including enhanced recovery pathways, as well as elective critical care admission. With discoveries of new effective interventions, and advances in healthcare information technology, optimized pathways could be developed to provide the best care possible that meets the challenges of perioperative frailty.

The Optimal Fluid Strategy Matters in Liver Surgery: A Retrospective Single Centre Analysis of 666 Consecutive Liver Resections

As optimal intraoperative fluid management in liver surgery has not been established, we retrospectively analyzed our fluid strategy in a high-volume liver surgery center in 666 liver resections. Intraoperative fluid management was divided into very restrictive (<10 m kg^-1 h^-1) and normal (≥10 mL kg^-1 h^-1) groups for study group characterization. The primary endpoint was morbidity as assessed by the Clavien-Dindo (CD) score and the comprehensive complication index (CCI). Logistic regression models identified factors most predictive of postoperative morbidity. No association was found between postoperative morbidity and fluid management in the overall study population (p = 0.89). However, the normal fluid management group had shorter postoperative hospital stays (p = <0.001), shorter ICU stays (p = 0.035), and lower in-hospital mortality (p = 0.02). Elevated lactate levels (p < 0.001), duration (p < 0.001), and extent of surgery (p < 0.001) were the most predictive factors for postoperative morbidity. In the subgroup of major/extreme liver resection, very low total (p = 0.028) and normalized fluid balance (p = 0.025) (NFB) were associated with morbidity. Moreover, fluid management was not associated with morbidity in patients with normal lactate levels (<2.5 mmol/L). In conclusion, fluid management in liver surgery is multifaceted and must be applied judiciously as a therapeutic measure. While a restrictive strategy appears attractive, hypovolemia should be avoided.

Goal-directed haemodynamic therapy: an imprecise umbrella term to avoid

'Goal-directed haemodynamic therapy' describes various haemodynamic treatment strategies that have in common that interventions are titrated to achieve predefined haemodynamic targets. However, the treatment strategies differ substantially regarding the underlying haemodynamic target variables and target values, and thus presumably have different effects on outcome. It is an over-simplifying approach to lump complex and substantially differing haemodynamic treatment strategies together under the term 'goal-directed haemodynamic therapy', an imprecise umbrella term that we should thus stop using.

Perioperative goal-directed therapy and postoperative complications in different kind of surgical procedures: an updated meta-analysis

BACKGROUND

Goal-directed therapy (GDT) aims to assure tissue perfusion, by optimizing doses and timing of fluids, inotropes, and vasopressors, through monitoring of cardiac output and other basic hemodynamic parameters. Several meta-analyses confirm that GDT can reduce postoperative complications. However, all recent evidences focused on high-risk patients and on major abdominal surgery.

OBJECTIVES

The aim of the present meta-analysis is to investigate the effect of GDT on postoperative complications (defined as number of patients with a least one postoperative complication) in different kind of surgical procedures.

DATA SOURCES

Randomized controlled trials (RCTs) on perioperative GDT in adult surgical patients were included. The primary outcome measure was complications, defined as number of patients with at least one postoperative complication. A subgroup-analysis was performed considering the kind of surgery: major abdominal (including also major vascular), only vascular, only orthopedic surgery. and so on.

STUDY APPRAISAL AND SYNTHESIS METHODS

Meta-analytic techniques (analysis software RevMan, version 5.3.5, Cochrane Collaboration, Oxford, England, UK) were used to combine studies using odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

In 52 RCTs, 6325 patients were enrolled. Of these, 3162 were randomized to perioperative GDT and 3153 were randomized to control. In the overall population, 2836 patients developed at least one complication: 1278 (40%) were randomized to perioperative GDT, and 1558 (49%) were randomized to control. Pooled OR was 0.60 and 95% CI was 0.49-0.72. The sensitivity analysis confirmed the main result. The analysis enrolling major abdominal patients showed a significant result (OR 0.72, 95% CI 0.59-0.87, p = 0.0007, 31 RCTs, 4203 patients), both in high- and low-risk patients. A significant effect was observed in those RCTs enrolling exclusively orthopedic procedures (OR 0.53, 95% CI 0.35-0.80, p = 0.002, 7 RCTs, 650 patients. Also neurosurgical procedures seemed to benefit from GDT (OR 0.40, 95% CI 0.21-0.78, p = 0.008, 2 RCTs, 208 patients). In both major abdominal and orthopedic surgery, a strategy adopting fluids and inotropes yielded significant results. The total volume of fluid was not significantly different between the GDT and the control group.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

The present meta-analysis, within the limits of the existing data, the clinical and statistical heterogeneity, suggests that GDT can reduce postoperative complication rate. Moreover, the beneficial effect of GDT on postoperative morbidity is significant on major abdominal, orthopedic and neurosurgical procedures. Several well-designed RCTs are needed to further explore the effect of GDT in different kind of surgeries.

Observational study on fluid therapy management in surgical adult patients

Background

Perioperative fluid therapy management is changing due to the incorporation of different fluids, surgical techniques, and minimally invasive monitoring systems. The objective of this study was to explore fluid therapy management during the perioperative period in our country.

Methods

We designed the Fluid Day study as a cross-sectional, multicentre, observational study. The study was performed in 131 Spanish hospitals in February 2019. We included adult patients undergoing general anaesthesia for either elective or non-elective surgery. Demographic variables were recorded, as well as the type and total volume of fluid administered during the perioperative period and the monitorization used. To perform the analysis, patients were categorized by risk group.

Results

We recruited 7291 patients, 6314 of which were included in the analysis; 1541 (24.4%) patients underwent high-risk surgery, 1497 (23. 7%) were high risk patients, and 554 (8.7%) were high-risk patients and underwent high-risk surgery; 98% patients received crystalloids (80% balanced solutions); intraoperative colloids were used in 466 patients (7.51%). The hourly intraoperative volume in mL/kg/h and the median [Q1; Q3] administered volume (mL/kg) were, respectively, 6.67 [3.83; 8.17] ml/Kg/h and 13.9 [9.52;5.20] ml/Kg in low-risk patients undergoing low- or intermediate-risk surgery, 6 [4.04; 9.08] ml/Kg/h and 15.7 [10.4;24.5] ml/Kg in high- risk patients undergoing low or intermediate-risk surgery, 6.41 [4.36; 9.33] ml/Kg/h and 20.2 [13.3;32.4] ml/Kg in low-risk patients undergoing high-risk surgery, and 5.46 [3.83; 8.17] ml/Kg/h and 22.7[14.1;40.9] ml/Kg in high-risk patients undergoing high- risk surgery . We used advanced fluid monitoring strategies in 5% of patients in the intraoperative period and in 10% in the postoperative period.

Conclusions

The most widely used fluid was balanced crystalloids. Colloids were used in a small number of patients. Hourly surgery volume tended to be more restrictive in high-risk patients but confirms a high degree of variation in the perioperatively administered volume. Scarce monitorization was observed in fluid therapy management.

Trial registration

Clinical Trials: NCT03630744.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01518-z.

Comparison between capnodynamic and thermodilution method for cardiac output monitoring during major abdominal surgery: An observational study

BACKGROUND

Cardiac output (CO) monitoring is the basis of goal-directed treatment for major abdominal surgery. A capnodynamic method estimating cardiac output (COEPBF) by continuously calculating nonshunted pulmonary blood flow has previously shown good agreement and trending ability when evaluated in mechanically ventilated pigs.

OBJECTIVES

To compare the performance of the capnodynamic method of CO monitoring with transpulmonary thermodilution (COTPTD) in patients undergoing major abdominal surgery.

DESIGN

Prospective, observational, method comparison study. Simultaneous measurements of COEPBF and COTPTD were performed before incision at baseline and before and after increased (+10 cmH2O) positive end-expiratory pressure (PEEP), activation of epidural anaesthesia and intra-operative events of hypovolemia and low CO. The first 25 patients were ventilated with PEEP 5 cmH2O (PEEP5), while in the last 10 patients, lung recruitment followed by individual PEEP adjustment (PEEPadj) was performed before protocol start.

SETTING

Karolinska University Hospital, Stockholm, Sweden.

PATIENTS

In total, 35 patients (>18 years) scheduled for major abdominal surgery with advanced hemodynamic monitoring were included in the study.

MAIN OUTCOME MEASURES AND ANALYSIS

Agreement and trending ability between COEPBF and COTPTD at different clinical moments were analysed with Bland--Altman and four quadrant plots.

RESULTS

In total, 322 paired values, 227 in PEEP5 and 95 in PEEPadj were analysed. Respectively, the mean COEPBF and COTPTD were 4.5 ± 1.0 and 4.8 ± 1.1 in the PEEP5 group and 4.9 ± 1.2 and 5.0 ± 1.0 l min-1 in the PEEPadj group. Mean bias (levels of agreement) and percentage error (PE) were -0.2 (-2.2 to 1.7) l min-1 and 41% for the PEEP5 group and -0.1 (-1.7 to 1.5) l min-1 and 31% in the PEEPadj group. Concordance rates during changes in COEPBF and COTPTD were 92% in the PEEP5 group and 90% in the PEEPadj group.

CONCLUSION

COEPBF provides continuous noninvasive CO estimation with acceptable performance, which improved after lung recruitment and PEEP adjustment, although not interchangeable with COTPTD. This method may become a tool for continuous intra-operative CO monitoring during general anaesthesia in the future.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT03444545.

Perioperative hemodynamic optimization in laparoscopic sleeve gastrectomy using stroke volume variation to reduce postoperative nausea and vomiting

BACKGROUND

Risk of postoperative nausea and vomiting (PONV) is usually high among patients undergoing laparoscopic sleeve gastrectomy (LSG). Perioperative hemodynamic optimization using goal-directed fluid therapy (GDFT) based on stroke volume variation (SVV) has been suggested to reduce PONV.

OBJECTIVES

This study aimed to investigate the effectiveness of GDFT on reducing PONV.

SETTING

The operating rooms in China Medical University Hospital.

METHODS

This prospective cohort study included 75 patients undergoing LSG. Patients were randomized into 3 groups: controls (conventional fluid therapy), GDFT-hydroxyethyl starch (GH), and GDFT-lactated Ringer's (GL) groups. In both GDFT groups, optimization of fluid administration was achieved by continuous monitoring and adjusting of SVV. Severity of PONV was evaluated using a standardized questionnaire. Other clinically relevant events, including in-hospital surgical site infections and length of hospital stay were also investigated.

RESULTS

In the GH group, the total volume of fluid administered intraoperatively was significantly lower than that in the GL and control groups (P < .001). Assessment of PONV severity showed a significantly higher score at postoperative 24 hours in the GH group (P < .05), while no significant differences were found between the 3 groups at postoperative 48 hours. No significant differences were observed between the 3 groups in surgical site infections and length of hospital stay.

CONCLUSION

No significant benefit is found in reducing PONV by using GDFT in patients undergoing LSG, although GDFT effectively avoids excessive volume of fluid administration. PONV incidence appears to be higher with intraoperative colloid infusion for GDFT during LSG. Further investigation is warranted to elucidate the mechanism underlying PONV in postoperative LSG.

Preoperative carbohydrate loading and intraoperative goal-directed fluid therapy for elderly patients undergoing open gastrointestinal surgery: a prospective randomized controlled trial

Background

The effect of a combination of a goal-directed fluid protocol and preoperative carbohydrate loading on postoperative complications in elderly patients still remains unknown. Therefore, we designed this trial to evaluate the relative impact of preoperative carbohydrate loading and intraoperative goal-directed fluid therapy versus conventional fluid therapy (CFT) on clinical outcomes in elderly patients following gastrointestinal surgery.

Methods

This prospective randomized controlled trial with 120 patients over 65years undergoing gastrointestinal surgery were randomized into a CFT group (n=60) with traditional methods of fasting and water-deprivation, and a GDFT group (n=60) with carbohydrate (200ml) loading 2h before surgery. The CFT group underwent routine monitoring during surgery, however, the GDFT group was conducted by a Vigileo/FloTrac monitor with cardiac index (CI), stroke volume variation (SVV), and mean arterial pressure (MAP). For all patients, demographic data, intraoperative parameters and postoperative outcomes were recorded.

Results

Patients in the GDFT group received significantly less crystalloids fluid (1111442.9ml vs 1411412.6ml; p<0.001) and produced significantly less urine output (200ml [150300] vs 400ml [290500]; p<0.001) as compared to the CFT group. Moreover, GDFT was associated with a shorter average time to first flatus (5614.1h vs 6422.3h; p=0.002) and oral intake (7216.9h vs 8526.8h; p=0.011), as well as a reduction in the rate of postoperative complications (15 (25.0%) vs 29 (48.3%) patients; p=0.013). However, postoperative hospitalization or hospitalization expenses were similar between groups (p>0.05).

Conclusions

Focused on elderly patients undergoing open gastrointestinal surgery, we found perioperative fluid optimisation may be associated with improvement of bowel function and a lower incidence of postoperative complications.

Trial registration

ChiCTR, ChiCTR1800018227. Registered 6 September 2018 - Retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01377-8.

Studying Enhanced Recovery After Surgery (ERAS®) Core Items in Colorectal Surgery: A Causal Model with Latent Variables

Background

Previous Enhanced Recovery After Surgery (ERAS®) studies have not always taken into account that ERAS interventions depend on baseline covariates and that several confounding variables affect the composite outcomes.

Method

A causal latent variable model is proposed to analyze data obtained prospectively concerning 1261 patients undergoing elective colorectal surgery within the ERAS protocol. Primary outcomes (composite of any complication, surgical site infection, medical complications, early ready for discharge (TRD), early actual discharge) and secondary outcomes (composite of late bowel function recovery, IV fluid resumption, nasogastric tube replacement, postoperative nausea and vomiting, re-intervention, re-admission, death) are considered along with their multiple dimensions.

Results

Concerning the primary outcomes, our results evidence three subpopulations of patients: one with probable good outcome, one with possibly prolonged TRD and discharge without complications, and the other one with probable complications and prolonged TRD and discharge. Epidural anesthesia, waiving surgical drainage, and early ambulation, IV fluid stop and urinary catheter removal act favorably, while preoperative hospital stay and blood transfusion act negatively. Concerning the secondary outcomes our results evidence two subpopulations of patients: one with high probability of good outcome and one with high probability of complications. Epidural anesthesia, waiving surgical drainage, early ambulation and IV fluid stop act favorably, while blood transfusion acts negatively also with respect to these secondary outcomes.

Conclusion

The multivariate causal latent class two-parameter logistic model, a modern statistical method overcoming drawbacks of traditional models to estimate the average causal effects on the treated, allows us to disentangle subpopulations of patients and to evaluate ERAS interventions.

Goal-directed fluid therapy in autologous breast reconstruction results in less fluid and more vasopressor administration without outcome compromise

OBJECTIVE

Aggressive or restricted perioperative fluid management has been shown to increase complications in patients undergoing microsurgery. Goal-directed fluid therapy (GDFT) aims to administer fluid, vasoactive agents, and inotropes according to each patient's hemodynamic indices. This study assesses GDFT impact on perioperative outcomes of autologous breast reconstruction (ABR) patients, as there remains a gap in management understanding. We hypothesize that GDFT will have lower fluid administration and equivocal outcomes compared to patients not on GDFT.

METHODS

A single-center retrospective review was conducted on ABR patients from January 2010-April 2017. An enhanced recovery after surgery (ERAS) using GDFT was implemented in April 2015. With GDFT, patients were administered intraoperative fluids and vasoactive agents according to hemodynamic indices. Patients prior to April 2015 were included in the pre-ERAS cohort. Primary outcomes included the amount and rate of fluid delivery, urine output (UOP), vasopressor administration, major (i.e., flap failure) and minor (i.e., seroma) complications, and length of stay (LOS).

RESULTS

Overall, 777 patients underwent ABR (ERAS: 312 and pre-ERAS: 465). ERAS patients received significantly less total fluid volume (ERAS median: 3750 mL [IQR: 3000-4500 mL]; pre-ERAS median: 5000 mL [IQR 4000-6400 mL]; and p<0.001), had lower UOP, were more likely to receive vasopressor agents (47% vs 35% and p<0.001), and had lower LOS (ERAS: 4 days [4-5]; pre-ERAS: 5 [4-6]; and p<0.001) as compared to pre-ERAS patients. Complications did not differ between cohorts.

CONCLUSIONS

GDFT, as part of ERAS, and the prudent use of vasopressors were found to be safe and did not increase morbidity in ABR patients. GDFT provides individualized perioperative care to the ABR patient.

Dobutamine-sparing versus dobutamine-to-all strategy in cardiac surgery: a randomized noninferiority trial

Background

The detrimental effects of inotropes are well-known, and in many fields they are only used within a goal-directed therapy approach. Nevertheless, standard management in many centers includes administering inotropes to all patients undergoing cardiac surgery to prevent low cardiac output syndrome and its implications. Randomized evidence in favor of a patient-tailored, inotrope-sparing approach is still lacking. We designed a randomized controlled noninferiority trial in patients undergoing cardiac surgery with normal ejection fraction to assess whether an dobutamine-sparing strategy (in which the use of dobutamine was guided by hemodynamic evidence of low cardiac output associated with signs of inadequate tissue perfusion) was noninferior to an inotrope-to-all strategy (in which all patients received dobutamine).

Results

A total of 160 patients were randomized to the dobutamine-sparing strategy (80 patients) or to the dobutamine-to-all approach (80 patients). The primary composite endpoint of 30-day mortality or occurrence of major cardiovascular complications (arrhythmias, acute myocardial infarction, low cardiac output syndrome and stroke or transient ischemic attack) occurred in 25/80 (31%) patients of the dobutamine-sparing group (p = 0.74) and 27/80 (34%) of the dobutamine-to-all group. There were no significant differences between groups regarding the incidence of acute kidney injury, prolonged mechanical ventilation, intensive care unit or hospital length of stay.

Discussion

Although it is common practice in many centers to administer inotropes to all patients undergoing cardiac surgery, a dobutamine-sparing strategy did not result in an increase of mortality or occurrence of major cardiovascular events when compared to a dobutamine-to-all strategy. Further research is needed to assess if reducing the administration of inotropes can improve outcomes in cardiac surgery.

Trial registration ClinicalTrials.gov, NCT02361801. Registered Feb 2nd, 2015. https://clinicaltrials.gov/ct2/show/NCT02361801

To compare intraoperative goal directed fluid therapy by trans-oesophageal Doppler vis-à-vis FloTrac™ in patients undergoing living related renal transplantation-a prospective randomised controlled study

Background:

Optimal intra-operative fluid therapy in renal transplantation (RT) is essential to ensure adequate graft function while preventing fluid overload related complications. This RCT was to compare the intraoperative goal directed fluid therapy (GDFT) based either on corrected flow time (CFT), measured by trans oesophageal Doppler (TED) or on the stroke volume variation (SVV), by FloTrac in patients undergoing living donor RT.

Methods:

This prospective, randomised controlled trial (RCT) was done on 60 end stage renal disease (ESRD) patients, American Society of Anaesthesiologists(ASA) grade III–IV, age 18 to 65 years of either sex, scheduled for living donor RT under general anaesthesia. They were randomly divided into two groups: TED group (n = 30) and FloTrac™ group (n = 30) and administered GDFT, based upon CFT (TED) and SVV (FloTrac™). The primary outcome was to compare the total fluid and number of fluid boluses administered intraoperatively, while the secondary outcomes were to compare any postoperative complications due to fluid overload and allograft function, assessed by serial serum creatinine levels up to 90 days postoperatively.

Results:

The mean total intra-operative fluid [3991.67 ± 856.32 vs. 3543.33 ± 1131.35, P = 0.089] and the amount of fluid administered per kg body weight per hour [13.32 ± 4.67 vs. 11.82 ± 4.76, P = 0.222] were lesser in the FloTrac compared to TED group, though not statistically significant. However, the postoperative incidence of allograft dysfunction, including rejection (P = 0.743) and acute tubular necrosis (ATN) (P = 0.999), and other complications (P = 0.643) were comparable.

Conclusions:

Both TED and FloTrac devices can be used effectively to guide GDFT in RT, However, lesser total fluid was required in the FloTrac group, which may lead to a lesser number of fluid-related postoperative complications.

Effect of Intraoperative Goal-Directed Fluid Management on Tissue Oxygen Tension in Obese Patients: a Randomized Controlled Trial

Background

Perioperative subcutaneous tissue oxygen tension (PsqO₂) is substantially reduced in obese surgical patients. Goal-directed fluid therapy optimizes cardiac performance and thus tissue perfusion and oxygen delivery. We therefore tested the hypothesis that intra- and postoperative PsqO₂ is significantly reduced in obese patients undergoing standard fluid management compared to goal-directed fluid administration.

Methods

We randomly assigned 60 obese patients (BMI ≥ 30 kg/m²) undergoing laparoscopic bariatric surgery to receive either esophageal Doppler-guided goal-directed fluid management or conventional fluid treatment. Our primary outcome parameter was intra- and postoperative PsqO₂ measured with a polarographic electrode in the subcutaneous tissue of the upper arm. A random effects linear regression model was used to analyze the effect of intervention.

Results

Overall, mean (± SD) PsqO₂ was significantly higher in obese patients receiving goal-directed therapy compared to conventional fluid therapy (65.8 ± 28.0 mmHg vs. 53.7 ± 21.7, respectively; repeated measures design adjusted difference: 13.0 mmHg [95% CI 2.3 to 23.7; p = 0.017]). No effect was seen intraoperatively (69.6 ± 27.9 mmHg vs. 61.4 ± 28.8, difference: 9.7 mmHg [95% CI -3.8 to 23.2; p = 0.160]); however, goal-directed fluid management improved PsqO₂ in the early postoperative phase (63.1 ± 27.9 mmHg vs. 48.4 ± 12.5, difference: 14.5 mmHg [95% CI 4.1 to 24.9; p = 0.006]). Intraoperative fluid requirements did not differ between the two groups.

Conclusions

Goal-directed fluid therapy improved subcutaneous tissue oxygenation in obese patients. This effect was more pronounced in the early postoperative period.

Clinical Trial Number and Registry

The study was registered at ClinicalTrials.gov (NCT 01052519).

The effect of adding goal-directed hemodynamic management for elective patients in an established enhanced recovery program for colorectal surgery: results of quasi-experimental pragmatic trial

Background

Recent literature has demonstrated that hemodynamic instability in the intraoperative period places patients at risk of poor outcomes. Furthermore, recent studies have reported that stroke volume optimization and protocolized hemodynamic management may improve perioperative outcomes, especially surgical site infection (SSI), in certain high-risk populations. However, the optimal strategy for intraoperative management of all elective patients within an enhanced recovery program remains to be elucidated.

Methods

We performed a pre-post quasi-experimental study to assess the effect of adding goal-directed hemodynamic therapy to an enhanced recovery program (ERP) for colorectal surgery on SSI and other outcomes. Three groups were compared: “Pre-ERP,” defined as historical control (before enhanced recovery program); “ERP,” defined as enhanced recovery program using zero fluid balance; and “ERP+GDHT,” defined as enhanced recovery program plus goal-directed hemodynamic therapy. Outcomes were obtained through our National Surgical Quality Improvement Program participation.

Results

A total of 623 patients were included in the final analysis (Pre-ERP = 246, ERP = 140, and ERP + GDHT = 237). Demographics and baseline clinical characteristics were balanced between groups. We did not observe statistically significant differences in SSI or composite complication rates in unadjusted or adjusted analysis. There was no evidence of association between study group and 30-day readmission. American Society of Anesthesiologists status ≥ 3 and open surgical approach were significantly associated with increased risk of SSI, composite complication, and 30-day readmission (p < 0.05 for all) in all groups.

Conclusions

There was no evidence that addition of goal-directed hemodynamic therapy for all patients in an enhanced recovery program for colorectal surgery affects the risk of SSI, composite complications, or 30-day readmission. Further research is needed to investigate whether there is benefit of goal-directed hemodynamic therapy for select high-risk populations.

Trial registration

NCT03189550. Registered 16 June 2017–Retrospectively registered, https://www.clinicaltrials.gov/ct2/results?cond=&term=NCT03189550&cntry=&state=&city=&dist=

Classification and differential effectiveness of goal-directed hemodynamic therapies in surgical patients: A network meta-analysis of randomized controlled trials

PURPOSE

To investigate the most effective goal-directed hemodynamic therapy (GDHT) in surgical patients.

METHODS

GDHTs were classified as methods for intravascular volume, preload, stroke volume, cardiac output, oxygen delivery, systemic oxygenation, or tissue oxygenation optimization, alone or in combination. Their relative effectiveness and ranking were assessed using network meta-analysis and the surface under the cumulative ranking curve (SUCRA), respectively.

RESULTS

101 randomized controlled trials investigating GDHT effectiveness in surgical patients were eligible. The most commonly reported outcomes were 30-day mortality, acute kidney injury (AKI), and arrhythmia. Mortality was significantly reduced by GDHTs aimed at intravascular volume and cardiac output optimization (OR 0.40; 95% CrI 0.14-0.997; low quality). AKI was significantly reduced by GDHT aimed at intravascular volume optimization (OR 0.26; 95% CrI 0.08-0.71; moderate quality). No GDHT significantly reduced arrhythmia. GDHT aimed at intravascular volume and stroke volume optimization was likely most effective for mortality reduction (SUCRA = 78.8%) while that aimed at intravascular volume, stroke volume, and cardiac output optimization was likely most effective for AKI reduction (SUCRA = 85.4%).

CONCLUSIONS

Different GDHTs likely have different and outcome-dependent effectiveness in surgical patients. GDHTs aimed at intravascular volume, stroke volume, and cardiac output optimization are likely most effective as per the overall evidence.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number: CRD42020159978.

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.

Postoperative outcomes based on crystalloid administration in pediatric patients with necrotizing enterocolitis undergoing laparotomy

Intravenous fluid prescription is an essential part of postoperative care and may play a causal role in postoperative complications. The objective of the present study was to evaluate the relationship between intraoperative fluid administration and postoperative outcomes in a large cohort of pediatric patients.This analysis included a retrospective review of 172 patients who underwent gastroenterological surgery from January 2012 to September 2018 at an academic tertiary care hospital. Patients were evaluated based on the median amount of corrected crystalloids and subsequently dichotomized as low (<25.89 mL/kg h) versus high (>25.89 mL/kg h). The primary outcome measure was the postoperative length of hospital stay (pLOS). Secondary outcome measures included the postoperative time to restore gastroenterological functions and postoperative complications.Patients who received larger amounts of crystalloids were more likely to have a lower intraoperative level of hemoglobin (P = .78) and an intraoperative blood transfusion (P = .27). There were trends toward lower incidence rates of hyperchloremic acidosis (P = .375) and metabolic acidosis (P = .54) in the high crystalloid administration cohort. The incidence of postoperative complications increased as the amount of administered fluid decreased (P = .046). The total length of hospital stay was shorter in patients who received high volumes of crystalloid fluid (19.5 [15.75-32.25] days) than in patients who received low volumes (22 [16-29.5] days, P = .283).Significant and multifaceted variability in crystalloid administration was noted among pediatric patients undergoing major surgery. High fluid administration was associated with favorable postoperative outcomes; these findings could be applied to improve patient safety and facilitate better quality of care.

The need for post-operative vasopressor infusions after major gynae-oncologic surgery within an ERAS (Enhanced Recovery After Surgery) pathway

BACKGROUND

Hypotension following major abdominal surgery is common, and once hypovolaemia has been optimally treated, is often due to vasodilation which can be treated with vasopressor infusions. There is unpredictability in the dose and duration of post-operative vasopressor infusions, and factors associated with this have not been determined.

METHODS

We present a case series of consecutive patients who received major gynae-oncology surgery delivered within an Enhanced Recovery After Surgery (ERAS) pathway at a single institution. Patients were electively admitted from theatre directly to the intensive care unit (ICU). Data was collected prospectively into electronic databases (Philips ICCA, Wardwatcher) and then retrospectively collated and appropriate statistical analyses were performed. In the absence of a consensus definition of vasoplegia, we, necessarily arbitrarily, chose a noradrenaline dose of > 0.1 mcg/kg/min at 08:00 on the first post-operative day. The rationale is that this would be more than would typically be expected to counteract the vasodilatory effects of epidural analgesia, which is commonly used at our institution.

RESULTS

Data was collected from 324 patients, all treated between February 2014 and July 2016. The average age was 67 years and 39% received neoadjuvant chemotherapy. The commonest tumour type was ovarian (58%). The median estimated blood loss was 800 ml and epidural analgesia was used in 71%. Fifty per cent received post-operative vasopressor infusions: factors associated with this included epidural use and estimated blood loss. Nineteen per cent met our criteria for vasoplegia: factors associated with this included CRP on post-operative day 1 and P-POSSUM morbidity score. Hospital and ICU length of stay was prolonged in those who had vasoplegia.

CONCLUSIONS

Patients commonly receive vasopressors following major gynae-oncologic surgery, and this can be at relatively high doses. Clinical factors only accounted for a minority of the variability in vasopressor usage-suggesting considerable biological variability. Optimal care of patients having major abdomino-pelvic surgery may include advanced haemodynamic monitoring and ready availability of infused vasopressors, in a suitable environment.

The effect of intraoperative goal-directed crystalloid versus colloid administration on perioperative inflammatory markers - a substudy of a randomized controlled trial

Background

Excessive perioperative fluid administration may result in iatrogenic endothelial dysfunction and tissue edema, transducing inflammatory markers into the bloodstream. Colloids remain longer in the circulation, requiring less volume to reach similar hemodynamic endpoints compared to crystalloids. Thus, we tested the hypothesis that a goal-directed colloid regimen attenuates the inflammatory response compared to a goal-directed crystalloid regime.

Methods

Patients undergoing moderate- to high-risk open abdominal surgery were randomly assigned to goal-directed lactated Ringer’s solution (n = 58) or a hydroxyethyl starch 6% 130/0.4 (n = 62) fluid regimen. Our primary outcome was perioperative levels of pro- and anti-inflammatory cytokines. Secondary outcome was perioperative levels of white blood cell count (WBC), C-reactive protein (CRP), procalcitonin (PCT) and lipopolysaccharide-binding protein (LBP). Measurements were performed preoperatively, immediate postoperatively, on postoperative day one, two and four.

Results

The areas under the curve of Interleukin (IL) 6 (p = 0.60), IL 8 (p = 0.46), IL 10 (p = 0.68) and tumor necrosis factor α (p = 0.47) levels did not differ significantly between the groups. WBC, CRP and PCT values were also comparable. LBP, although significantly higher in the crystalloid group, remained in the normal range. Patients assigned to crystalloids received a median (IQR) amount of 3905 mL (2880–5288) of crystalloid. Patients assigned to colloids received 1557 mL (1207–2116) of crystalloid and 1250 mL (750–1938) of colloid.

Conclusion

Cytokine and inflammatory marker levels did not differ between goal-directed crystalloid and colloid administration after moderate to high-risk abdominal surgery.

Trial registration

ClinicalTrials.gov (NCT00517127). Registered 16th August 2007.

Estimated oxygen extraction versus dynamic parameters of fluid-responsiveness for perioperative hemodynamic optimization of patients undergoing non-cardiac surgery: a non-inferiority randomized controlled trial

BACKGROUND

Goal directed therapy (GDT) is able to improve mortality and reduce complications in selected high-risk patients undergoing major surgery. The aim of this study is to compare two different strategies of perioperative hemodynamic optimization: one based on optimization of preload using dynamic parameters of fluid-responsiveness and the other one based on estimated oxygen extraction rate (O2ER) as target of hemodynamic manipulation.

METHODS

This is a multicenter randomized controlled trial. Adult patients undergoing elective major open abdominal surgery will be allocated to receive a protocol based on dynamic parameters of fluid-responsiveness or a protocol based on estimated O2ER. The hemodynamic optimization will be continued for 6 h postoperatively. The primary outcome is difference in overall postoperative complications rate between the two protocol groups. Fluids administered, fluid balance, utilization of vasoactive drugs, hospital length of stay and mortality at 28 day will also be assessed.

DISCUSSION

As a predefined target of cardiac output (CO) or oxygen delivery (DO2) seems to be not adequate for every patient, a personalized therapy is likely more appropriate. Following this concept, dynamic parameters of fluid-responsiveness allow to titrate fluid administration aiming CO increase but avoiding fluid overload. This approach has the advantage of personalized fluid therapy, but it does not consider if CO is adequate or not. A protocol based on O2ER considers this second important aspect. Although positive effects of perioperative GDT have been clearly demonstrated, currently studies comparing different strategies of hemodynamic optimization are lacking.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04053595. Registered on 12/08/2019.

Intraoperative fluid therapy and postoperative complications during minimally invasive esophagectomy for esophageal cancer: a single-center retrospective study

PURPOSE

Compared with open thoracotomy, minimally invasive esophagectomy (MIE) methods, such as transhiatal or thoracoscopic esophagectomy, likely have lower morbidity. However, the relationship between intraoperative fluid management and postoperative complications after MIE remains unclear. Thus, we investigated the association of cumulative intraoperative fluid balance and postoperative complications in patients undergoing MIE.

METHODS

This single-center retrospective cohort study examined patients undergoing thoracoscopic esophagectomy for esophageal cancer in the prone position. Postoperative complications included pneumonia, arrhythmia, thrombotic events and acute kidney injury (AKI). We compared patients with higher and lower intraoperative fluid balance (higher and lower than the median). Multivariable logistic regression analyses were performed to estimate the odds ratio of intraoperative fluid balance status on the incidence of postoperative complications.

RESULTS

In total, 135 patients were included in the study. Postoperative complications occurred in 43 (32%), including cardiac arrhythmia (n = 12, 9%), thrombosis (n = 20, 15%), pneumonia (n = 13, 10%), and AKI required hemodialysis (n = 1, 1%). Patients with a higher fluid balance had higher incidence of complications than those with a lower fluid balance (46% vs. 18%, p < 0.001). After adjusting for age, ASA-PS ≥ III, blood loss, and the use of radical surgery, the higher intraoperative fluid balance group was significantly and independently associated with postoperative complications (adjusted OR 5.31, 95% CI 2.26-13.6, p < 0.0001).

CONCLUSIONS

In patients undergoing thoracoscopic esophagectomy in the prone position, a greater intraoperative positive fluid balance was independently associated with a higher incidence of complications.

Systematic review and meta-analysis of the perioperative use of vasoactive drugs on postoperative outcomes after major abdominal surgery

BACKGROUND

The perioperative use of vasoactive drugs is ubiquitous in clinical anaesthesia; yet, the drugs, doses, and haemodynamic targets used are highly variable. Our objectives were to determine whether the perioperative administration of vasoactive drugs reduces mortality, morbidity, and length of stay in adult patients (aged 16 yr or older) undergoing major abdominal surgery.

METHODS

MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched for peer-reviewed RCTs with no language or date restrictions. Studies that assessed the intraoperative use of vasoactive drugs were included. Title, abstract, and full-text screening was performed. Risk of bias for each outcome measure was conducted. We calculated the risk ratio (RR) using the Mantel-Haenszel random-effects model with corresponding 95% confidence interval (CI) for dichotomous outcomes, and mean difference using the inverse variance random-effects model with corresponding 95% CI for continuous outcomes.

RESULTS

Twenty-six studies (5561 participants) were included. There was no difference in mortality at the longest follow-up with an RR of 0.84 (95% CI: 0.63-1.12; P=0.23). The intervention significantly reduced the number of patients with one or more postoperative complications; RR: 0.76 (95% CI: 0.66-0.88; P=0.0002). Hospital length of stay was reduced by 0.91 days in the intervention group.

CONCLUSIONS

This review is limited by the quality and sample size of individual studies, and the heterogeneity of the settings, interventions, and outcome measures. Perioperative administration of vasoactive drugs may reduce postoperative complications and hospital length of stay in adult patients having major abdominal surgery.

Management of perioperative volume therapy - monitoring and pitfalls

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

Personalized Versus Protocolized Fluid Management Using Noninvasive Hemodynamic Monitoring (Clearsight System) in Patients Undergoing Moderate-Risk Abdominal Surgery

Advances in noninvasive hemodynamic monitoring systems allow delivery of goal-directed fluid therapy and could therefore be used in less-invasive surgical procedures. In this randomized controlled trial, we compared closed-loop-assisted goal-directed fluid therapy using a noninvasive cardiac output (Clearsight system) monitor (personalized approach) to a protocolized fluid therapy approach in 40 patients undergoing moderate-risk laparoscopic abdominal surgery. Cardiac output and stroke volume variations were not significantly different in both groups and remained within predefined target values >90% of the study time. Personalized fluid therapy does not seem to offer any hemodynamic advantage over a protocolized approach in this population.

Intraoperative Urine Output Is Associated with Postoperative Outcome in Pediatric Population Undergone Major Abdominal Operations

Aim

Few data support the advantage of confirming a low urine output target during Roux-en-Y hepaticojejunostomy, which was widely used as an indication for fluid administration. We aimed at evaluating postoperative outcomes in terms of urine output in pediatric patients undergoing elective Roux-en-Y hepaticojejunostomy.

Methods

We retrospectively reviewed 689 patients who had undergone Roux-en-Y hepaticojejunostomy between January 2007 and August 2014 at the Children’s Hospital of the Chongqing Medical University. Patients were dichotomized according to the average amount of corrected urine output (6.01 mL/kg*h) as a cut-off point. The primary endpoint was the occurrence of renal complications. The secondary endpoints included prompt postoperative gastrointestinal function recovery, postoperative complications and hospital length of stay.

Results

The lower urine output had a proportional association with lesser amounts of crystalloid fluids (12.99±6.52 and 17.36±7.74 mL/kg*h for low and high urine output, respectively, p=0.006). For patients with a lower urine output, there were trends toward lower incidence rates of grade II postoperative complications (OR, 0.68; 95CI, 0.45–1.03; p=0.041) and accelerated recovery of gastrointestinal function, as indicated by the first flatus (p=0.015) and first bowel movement (p=0.008); however, the occurrence of renal complications did not show significant differences between the groups. The total length of hospital stay was shorter in patients with low urine output (7.59±1.24 days) than that in patients with a high urine output (8.01±2.31 days, p = 0.016).

Conclusion

Lower urine output is associated with a lower incidence rate II postoperative complications and accelerated recovery of gastrointestinal function, without increasing the occurrence of renal complications in pediatric patient undergone hepaticojejunostomy. The optimal amount of urine output and associated fluid administration should be further investigated.

Fluid Therapy in Patients Undergoing Abdominal Surgery: A Bumpy Road Towards Individualized Management

Prudent intraoperative fluid replacement therapy, inotropes, and vasoactive drugs should be guided by adequate hemodynamic monitoring. The study aimed to evaluate the single-centre practice on intraoperative fluid therapy in abdominal surgery (AS). The evaluation, based on a review of medical files, included 235 patients (103 men), aged 60 ± 15 years who underwent AS between September and November 2017. Fluid therapy was analyzed in terms of quality and quantity. There were 124 high-risk patients according to the American Society of Anaesthesiologists Classification (ASA Class 3+) and 89 high-risk procedures performed. The median duration of procedures was 175 (IQR 106-284) min. Eleven patients died post-operatively. The median fluids volume was 10.4 mL/kg/h of anaesthesia, including 9.1 mL/kg/h of crystalloids and 2.7 mL/kg/h of synthetic colloids. Patients undergoing longer than the median procedures received significantly fewer fluids than those who underwent shorter procedures. The volume of fluids in the longer procedures depended on the procedural risk classification and was significantly greater in high-risk patients undergoing high-risk surgery. Patients who died received significantly more fluids than survivors. In all patients, a non-invasive blood pressure monitoring was used and only six patients had therapy guided by metabolic equilibrium. The fluid therapy used was liberal but complied with the recommendations regarding the type of fluid and risk-adjusted dosing. Hemodynamic monitoring was suboptimal and requires modifications. In conclusion, the optimization of intraoperative fluid therapy requires a balanced and standardized approach consistent with treatment procedures.

Stroke Volume Variation and Stroke Volume Index Can Predict Fluid Responsiveness after Mini-Volume Challenge Test in Patients Undergoing Laparoscopic Cholecystectomy

Background and Objectives: For using appropriate goal-directed fluid therapy during the surgical conditions of pneumoperitoneum in the reverse Trendelenburg position, we investigated the predictability of various hemodynamic parameters for fluid responsiveness by using a mini-volume challenge test. Materials and Methods: 42 adult patients scheduled for laparoscopic cholecystectomy were enrolled. After general anesthesia was induced, CO₂ pneumoperitoneum was applied and the patient was placed in the reverse Trendelenburg position. The mini-volume challenge test was carried out with crystalloid 4 mL/kg over 10 min. Hemodynamic parameters, including stroke volume variation (SVV), cardiac index (CI), stroke volume index (SVI), mean arterial pressure (MAP), and heart rate (HR), were measured before and after the mini-volume challenge test. The positive fluid responsiveness was defined as an increase in stroke volume index ≥10% after the mini-volume challenge. For statistical analysis, a Shapiro-Wilk test was used to test the normality of the data. Continuous variables were compared using an unpaired t-test or the Mann-Whitney rank-sum test. Categorical data were compared using the chi-square test. A receiver operating characteristic curve analysis was used to assess the predictability of fluid responsiveness after the mini-volume challenge. Results: 31 patients were fluid responders. Compared with the MAP and HR, the SVV, CI, and SVI showed good predictability for fluid responsiveness after the mini-volume challenge test (area under the curve was 0.900, 0.833, and 0.909, respectively; all p-values were <0.0001). Conclusions: SVV and SVI effectively predicted fluid responsiveness after the mini-volume challenge test in patients placed under pneumoperitoneum and in the reverse Trendelenburg position.

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.

Early postoperative fluid retention is a strong predictor for complications after pancreatoduodenectomy

BACKGROUND

Perioperative fluid overload has been reported to increase complications after a variety of operative procedures. This study was conducted to investigate the incidence of fluid retention after pancreatic resection and its association with postoperative complications.

METHODS

Data from 1174 patients undergoing pancreatoduodenectomy between 2010 and 2016 were collected from the Swedish National Pancreatic and Periampullary Cancer Registry. Early postoperative fluid retention was defined as a weight gain ≥2 kg on postoperative day 1. Outcome measures were overall complications, as well as procedure-specific complications.

RESULTS

The weight change on postoperative day 1 ranged from -1 kg to +9 kg. A total of 782 patients (66.6%) were considered to have early fluid retention. Patients with fluid retention had significantly higher rates of total complications (p = 0.002), surgical complications (p = 0.001), pancreatic anastomotic leakage (p = 0.018) and wound infection (p = 0.023). Multivariable logistic regression confirmed early fluid retention as an independent risk factor for total complications (OR 1.46; p = 0.003), surgical complications (OR 1.49; p = 0.002), pancreatic anastomotic leakage (OR 1.48; p = 0.027) and wound infection (OR 1.84; p = 0.023).

CONCLUSIONS

Fluid retention is common after elective pancreatic resection, and its associated with an increased rate of postoperative complications.

Intraoperative Fluid Restriction is Associated with Functional Delayed Graft Function in Living Donor Kidney Transplantation: A Retrospective Cohort Analysis

Background: In 2016 we observed a marked increase in functional delayed graft function (fDGF) in our living donor kidney transplantation (LDKT) recipients from 8.5% in 2014 and 8.8% in 2015 to 23.0% in 2016. This increase coincided with the introduction of a goal-directed fluid therapy (GDFT) protocol in our kidney transplant recipients. Hereupon, we changed our intraoperative fluid regimen to a fixed amount of 50 mL/kg body weight (BW) and questioned whether the intraoperative fluid regimen was related to this increase in fDGF. Methods: a retrospective cohort analysis of all donors and recipients in our LDKT program between January 2014–February 2017 (n = 275 pairs). Results: Univariate analysis detected various risk factors for fDGF. Dialysis dependent recipients were more likely to develop fDGF compared to pre-emptively transplanted patients (p < 0.001). Recipients developing fDGF received less intraoperative fluid (36 (25.9–50.0) mL/kg BW vs. 47 (37.3–55.6) mL/kg BW (p = 0.007)). The GDFT protocol resulted in a reduction of intraoperative fluid administration on average by 850 mL in total volume and 21% in mL/kg BW compared to our old protocol (p < 0.001). In the unadjusted analysis, a higher intraoperative fluid volume in mL/kg BW was associated with a lower risk for the developing fDGF (OR 0.967, CI (0.941–0.993)). After adjustment for the confounders, prior dialysis and the use of intraoperative noradrenaline, the relationship of fDGF with fluid volume was still apparent (OR 0.970, CI (0.943–0.998)). Conclusion: Implementation of a GDFT protocol led to reduced intraoperative fluid administration in the LDKT recipients. This intraoperative fluid restriction was associated with the development of fDGF.