'Liberal' vs. 'restrictive' perioperative fluid therapy--a critical assessment of the evidence

Conservative fluid resuscitation protocol does not reduce the incidence of reoperation for bleeding after emergency CABG

Reoperation for bleeding (ROB) after emergency coronary artery bypass grafting (eCABG) has been identified as an independent risk factor for mortality. Consecutively, the influence of fluid intake, fluid output, fluid balance, blood loss, and inotropic demand on ROB were analyzed. This retrospective single-center study included 265 patients undergoing eCABG between 2011 and 2020. From 2018, postoperative hemodynamic management was performed with lower volume administration and higher vasoactive support. The primary outcome measure was the incidence of ROB within 48 h according to altered fluid resuscitation strategy. Consecutively, the influence of fluid intake, fluid output, fluid balance, blood loss, and inotropic demand on ROB were analyzed. Incidence of ROB was independent from the volume resuscitation protocol (P = .3). The ROB group had a higher perioperative risk, which was observed in EuroSCORE II. Fluid intake (P = .021), fluid balance (P = .001), and norepinephrine administration (P = .004) were associated with ROB. Fluid output and blood loss were not associated with ROB (P = .22). Post-test probability was low among all variables. Although fluid management might have an impact on specific postoperative complications, different fluid resuscitation protocols did not alter the incidence of ROB after emergency CABG.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov registration number NCT04533698; date of registration: August 31, 2020 (retrospectively registered due to nature of the study); URL: https://classic.

CLINICALTRIALS

gov/ct2/show/NCT04533698.

Fluid Management in Acute Respiratory Failure

Fluid management in acute respiratory failure is an area of uncertainty requiring a delicate balance of resuscitation and fluid removal to manage hypoperfusion and avoidance of hypoxemia. Overall, a restrictive fluid strategy (minimizing fluid administration) and careful attention to overall fluid balance may be beneficial after initial resuscitation and does not have major side effects. Further studies are needed to improve our understanding of patients who will benefit from a restrictive or liberal fluid management strategy.

Pulse pressure variation guided goal-direct fluid therapy decreases postoperative complications in elderly patients undergoing laparoscopic radical resection of colorectal cancer: a randomized controlled trial

OBJECTIVE

The use of goal-directed fluid therapy (GDFT) has been shown to reduce complications and improve prognosis in high-risk abdominal surgery patients. However, the utilization of pulse pressure variation (PPV) guided GDFT in laparoscopic surgery remains a subject of debate. We hypothesized that utilizing PPV guidance for GDFT would optimize short-term prognosis in elderly patients undergoing laparoscopic radical resection for colorectal cancer compared to conventional fluid therapy.

METHODS

Elderly patients undergoing laparoscopic radical resection of colorectal cancer were randomized to receive either PPV guided GDFT or conventional fluid therapy and explore whether PPV guided GDFT can optimize the short-term prognosis of elderly patients undergoing laparoscopic radical resection of colorectal cancer compared with conventional fluid therapy.

RESULTS

The incidence of complications was significantly lower in the PPV group compared to the control group (32.8% vs. 57.1%, P = .009). Additionally, the PPV group had a lower occurrence of gastrointestinal dysfunction (19.0% vs. 39.3%, P = .017) and postoperative pneumonia (8.6% vs. 23.2%, P = .033) than the control group.

CONCLUSION

Utilizing PPV as a monitoring index for GDFT can improve short-term prognosis in elderly patients undergoing laparoscopic radical resection of colorectal cancer.

REGISTRATION NUMBER

ChiCTR2300067361; date of registration: January 5, 2023.

Implication of age-related changes on anesthesia management

Elderly patients have a high risk of perioperative morbidity and mortality. Pluri-morbidities, polypharmacy, and functional dependence may have a great impact on intraoperative management and request specific cautions. In addition to surgical stress, several perioperative noxious stimuli such as fasting, blood loss, postoperative pain, nausea and vomiting, drug adverse reactions, and immobility may trigger a derangement leading to perioperative complications. Older patients have a high risk of major hemodynamic derangement due to aging of the cardiovascular system and associated comorbidities. The hemodynamic monitoring as well as fluid therapy should be the most accurate as possible. Aging is accompanied by decreased renal function, which is related to a reduction in renal blood flow, renal mass, and the number and size of functioning nephrons. Drugs eliminated predominantly by the renal route need dosage adjustments based on residual renal function. Liver mass, hepatic blood flow, and intrinsic metabolic activity are decreased in the elderly, and all drugs metabolized by the liver have a variable half-life, thus requiring dose reduction. Decreased neural plasticity contributes to a high risk for postoperative delirium. Monitoring of anesthesia depth should be mandatory to avoid overdosage of hypnotic drugs. Prevention of postoperative pulmonary complications requires both protective ventilation strategies and adequate recovery of neuromuscular function at the end of surgery. Avoidance of hypothermia cannot be missed. The aim of this review is to describe comprehensive strategies for intraoperative management plans tailored to meet the unique needs of elderly surgical patients, thus improving outcomes in this vulnerable population.

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.

Haemoglobin drift in patients following Whipple's procedure

BACKGROUNDS

This study aims to identify the objective findings of haemoglobin (Hb) drift in patients that had a Whipple's procedure in the last 10 years, their transfusion status intraoperatively and post-operatively, the potential factors affecting Hb drift, and the outcomes following Hb drift.

METHODS

A retrospective study was conducted at Northern Health, Melbourne. All adult patients who were admitted for a Whipple's procedure from 2010 to 2020 were included and information collected retrospectively for demographics, pre-operative, operative and post-operative details.

RESULTS

A total of 103 patients were identified. The median Hb drift calculated from a Hb level at the end of operation was 27.0 g/L (IQR 18.0-34.0), and 21.4% of patients received a packed red blood cell (PRBC) transfusion during the post-operative period. Patients received a large amount of intraoperative fluid with a median of 4500 mL (IQR 3400-5600). Hb drift was statistically associated with intraoperative and post-operative fluid infusion leading to concurrent issues with electrolyte imbalance and diuresis.

CONCLUSION

Hb drift is a phenomenon that does happen in major operations such as a Whipple's procedure, likely secondary to fluid over-resuscitation. Considering the risk of fluid overload and blood transfusion, Hb drift in the setting of fluid over-resuscitation needs to be kept in mind prior to blood transfusion to avoid unnecessary complications and wasting of other precious resources.

Effects of intraoperative fluid balance during pancreatoduodenectomy on postoperative pancreatic fistula: an observational cohort study

BACKGROUND

Perioperative fluid management during major abdominal surgery has been controversial. Postoperative pancreatic fistula (POPF) is a critical complication of pancreaticoduodenectomy (PD). We conducted a retrospective cohort study to analyze the impact of intraoperative fluid balance on the development of POPF.

METHODS

This retrospective cohort study enrolled 567 patients who underwent open pancreaticoduodenectomy, and the demographic, laboratory, and medical data were recorded. All patients were categorized into four groups according to quartiles of intraoperative fluid balance. Multivariate logistic regression and restricted cubic splines (RCSs) were used to analyze the relationship between intraoperative fluid balance and POPF.

RESULTS

The intraoperative fluid balance of all patients ranged from -8.47 to 13.56 mL/kg/h. A total of 108 patients reported POPF, and the incidence was 19.0%. After adjusting for potential confounders and using restricted cubic splines, the dose‒response relationship between intraoperative fluid balance and POPF was found to be statistically insignificant. The incidences of bile leakage, postpancreatectomy hemorrhage, and delayed gastric emptying were 4.4%, 20.8%, and 14.8%, respectively. Intraoperative fluid balance was not associated with these abdominal complications. BMI ≥ 25 kg/m², preoperative blood glucose < 6 mmol/L, long surgery time, and lesions not located in the pancreas were independent risk factors for POPF.

CONCLUSION

The study did not find a significant association between intraoperative fluid balance and POPF. Well-designed multicenter studies are necessary to explore the association between intraoperative fluid balance and POPF.

Goal-directed fluid therapy guided by Plethysmographic Variability Index (PVI) versus conventional liberal fluid administration in children during elective abdominal surgery: A randomized controlled trial

BACKGROUND

PVI has been shown to be an accurate predictor of fluid responsiveness in paediatric patients. Evidence regarding the role of PVI to guide intraoperative fluid therapy in paediatric abdominal surgery is lacking. We aimed to assess the effect of PVI-guided fluid therapy on the volume of intraoperative fluids administered and post-operative biochemical and recovery profile in children undergoing elective abdominal surgery.

METHODS

42 children, 6 months-3 years scheduled for elective open bowel surgery were randomised to receive either 'conventional liberal intraoperative fluids' (liberal group) or 'goal-directed intraoperative fluids' (GDT group). PVI <13 was targeted in the GDT group. The primary outcome was the volume of intraoperative fluids administered. Postoperative serum lactate, base excess, hematocrit, recovery of bowel function and duration of postoperative hospital stay were the secondary outcomes.

RESULTS

The mean fluid administered intra-operatively was significantly lower in the GDT group as compared to the liberal group (24.1 ± 9.6 mL/kg vs 37.0 ± 8.9 mL/kg, p < 0.001). The postoperative hemoglobin concentration (g%) was significantly lower in the liberal group as compared to the GDT group (8.1 ± 1.3 vs 9.2 ± 1.4, p = 0.008). Recovery of bowel function (hours) was significantly delayed in the liberal group as compared to the GDT group (58.2 ± 17.9 vs 36.5 ± 14.1, p < 0.001).

CONCLUSION

Intraoperative PVI-guided fluid therapy significantly reduces the volume of intravenous crystalloids administered to children undergoing open bowel surgery. These children also had faster recovery of bowel function and less hemodilution in the immediate postoperative period, compared to those who received liberal intraoperative fluid therapy.

TYPE OF STUDY

Randomized Clinical Trial.

LEVEL OF EVIDENCE

Treatment Study (LEVEL 1).

Restricted Versus Liberal Versus Goal-Directed Fluid Therapy for Non-vascular Abdominal Surgery: A Network Meta-Analysis and Systematic Review

Optimal perioperative fluid management is crucial, with over- or under-replacement associated with complications. There are many strategies for fluid therapy, including liberal fluid therapy (LFT), restrictive fluid therapy (RFT) and goal-directed fluid therapy (GDT), without a clear consensus as to which is better. We aimed to find out which is the more effective fluid therapy option in adult surgical patients undergoing non-vascular abdominal surgery in the perioperative period. This study is a systematic review and network meta-analysis (NMA) with node-splitting analysis of inconsistency, sensitivity analysis and meta-regression. We conducted a literature search of Pubmed, Cochrane Library, EMBASE, Google Scholar and Web of Science. Only studies comparing restrictive, liberal and goal-directed fluid therapy during the perioperative phase in major non-cardiac surgery in adult patients will be included. Trials on paediatric patients, obstetric patients and cardiac surgery were excluded. Trials that focused on goal-directed therapy monitoring with pulmonary artery catheters and venous oxygen saturation (SvO2), as well as those examining purely biochemical and laboratory end points, were excluded. A total of 102 randomised controlled trials (RCTs) and 78 studies (12,100 patients) were included. NMA concluded that goal-directed fluid therapy utilising FloTrac was the most effective intervention in reducing the length of stay (LOS) (surface under cumulative ranking curve (SUCRA) = 91%, odds ratio (OR) = -2.4, 95% credible intervals (CrI) = -3.9 to -0.85) and wound complications (SUCRA = 86%, OR = 0.41, 95% CrI = 0.24 to 0.69). Goal-directed fluid therapy utilising pulse pressure variation was the most effective in reducing the complication rate (SUCRA = 80%, OR = 0.25, 95% CrI = 0.047 to 1.2), renal complications (SUCRA = 93%, OR = 0.23, 95% CrI = 0.045 to 1.0), respiratory complications (SUCRA = 74%, OR = 0.42, 95% CrI = 0.053 to 3.6) and cardiac complications (SUCRA = 97%, OR = 0.067, 95% CrI = 0.0058 to 0.57). Liberal fluid therapy was the most effective in reducing the mortality rate (SUCRA = 81%, OR = 0.40, 95% CrI = 0.12 to 1.5). Goal-directed therapy utilising oesophageal Doppler was the most effective in reducing anastomotic leak (SUCRA = 79%, OR = 0.45, 95% CrI = 0.12 to 1.5). There was no publication bias, but moderate to substantial heterogeneity was found in all networks. In preventing different complications, except mortality, goal-directed fluid therapy was consistently more highly ranked and effective than standard (SFT), liberal or restricted fluid therapy. The evidence grade was low quality to very low quality for all the results, except those for wound complications and anastomotic leak.

Blood volume in patients likely to be preload responsive: a post hoc analysis of a randomized controlled trial

BACKGROUND

Preload responsive postoperative patients with signs of inadequate organ perfusion are commonly assumed to be hypovolemic and therefore treated with fluids to increase preload. However, preload is influenced not only by blood volume, but also by venous vascular tone and the contribution of these factors to preload responsiveness in this setting is unknown. Based on this, the objective of this study was to investigate blood volume status in preload-responsive postoperative patients.

METHODS

Data from a clinical trial including postoperative patients after major abdominal surgery were analyzed. Patients with signs of inadequate organ perfusion and with data from a passive leg raising test (PLR) were included. An increase in pulse pressure by ≥ 9% was used to identify patients likely to be preload responsive. Blood volume was calculated from plasma volume measured using radiolabelled albumin and hematocrit. Patients with a blood volume of at least 10% above or below estimated normal volume were considered hyper- and hypovolemic, respectively.

RESULTS

A total of 63 patients were included in the study. Median (IQR) blood volume in the total was 57 (50-65) ml/kg, and change in pulse pressure after PLR was 14 (7-24)%. A total of 43 patients were preload responsive. Of these patients, 44% were hypovolemic, 28% euvolemic and 28% hypervolemic.

CONCLUSIONS

A large fraction of postoperative patients with signs of hypoperfusion that are likely to be preload responsive, are hypervolemic. In these patients, treatments other than fluid administration may be a more rational approach to increase cardiac output. Trial registration EudraCT 2013-004446-42.

Impact of Goal-Directed Fluid Therapy on Postoperative Outcomes in Colorectal Surgery: An Evidence-Based Review

PURPOSE

To investigate the effects of goal-directed fluid therapy (GDFT) or conventional fluid therapy (CFT) in improving postoperative outcomes in patients undergoing colorectal surgeries.

DESIGN

Evidence-Based Review.

METHODS

Following the guidelines outlined in the PRISMA statement, a comprehensive search was conducted using PubMed, Elsevier ScienceDirect, Oxford Academic, EBSCO, Google Scholar, Cochrane Library, and gray literature. Only randomized controlled studies and pre-appraised evidence such as systematic review with meta-analysis examining the effects of GDFT and CFT in colorectal surgery were included. The quality appraisal of the literature was conducted using the proposed algorithm described in the Johns Hopkins Nursing Evidence-Based Practice Evidence Level and Quality Guide.

FINDINGS

Two systematic reviews with meta-analyses and four randomized controlled trials (RCT) involving 2018 patients were included in this review. Overall, the use of GDFT did not shorten the hospital length of stay (LOS), reduce 30-day mortality, lower overall morbidity rates, or decrease incidence of postoperative ileus. Additionally, the return of bowel function was not improved using GDFT or CFT. However, when GDFT was implemented within enhanced recovery after surgery (ERAS) programs, there was a significant reduction in hospital LOS. . When GDFT was used in a non-ERAS patient care setting, there was a significant reduction in overall morbidity rate and faster time to first flatus. All studies included in the review were categorized as Level I and rated Grade A, implying strong confidence in the true effects of GDFT on all outcome measures in the review.

CONCLUSIONS

The benefits of GDFT in colorectal surgery are still unclear. Considerable heterogeneity based on the types of GDFT devices, patient outcome parameters, and fluid protocols limit the application to clinical practice. Furthermore, there was limited data on the effects of GDFT in high-risk patients for colorectal surgery.

Heat loss augmented by extracorporeal circulation is associated with overcooling in cardiac arrest survivors who underwent targeted temperature management

We investigated the association of extracorporeal circuit-based devices with temperature management and neurological outcome in out-of-hospital cardiac arrest survivors who underwent targeted temperature management. Patients with extracorporeal membrane oxygenation and/or continuous renal replacement therapy were classified as the extracorporeal group. We calculated the cooling rate during the induction period and time-weighted core temperatures (TWCT) during the maintenance period. We defined the sum of TWCT above or below 33 °C as positive and negative TWCT, respectively, and the sum of TWCT above 33.5 °C or below 32.5 °C as undercooling or overcooling, respectively. The primary outcome was the negative TWCT. The secondary outcomes were positive TWCT, cooling rate, undercooling, overcooling, and poor neurological outcomes, defined as Cerebral Performance Category 3–5. Among 235 patients, 150 (63.8%) had poor neurological outcomes and 52 (22.1%) were assigned to the extracorporeal group. The extracorporeal group (β, 0.307; p < 0.001) had increased negative TWCT, rapid cooling rate (1.77 °C/h [1.22–4.20] vs. 1.24 °C/h [0.77–1.79]; p = 0.005), lower positive TWCT (33.4 °C∙min [24.9–46.2] vs. 54.6 °C∙min [29.9–87.0]), and higher overcooling (5.01 °C min [0.00–10.08] vs. 0.33 °C min [0.00–3.78]). However, the neurological outcome was not associated with the use of extracorporeal devices (odds ratio, 1.675; 95% confidence interval, 0.685–4.094).

The Effects of Intravenous Fluid Viscosity on the Accuracy of Intravenous Infusion Flow Regulators

Intravenous infusion flow regulators (IIFRs) are widely used devices but it is unknown how much the difference between the IIFR scale and the actual flow rate depends on the viscosity of the intravenous (IV) fluid. This study evaluated the effects of viscosity on the flow rate of five IV fluids (0.9% normal saline, Hartmann's solution, plasma solution-A, 6% hetastarch, and 5% albumin) when using IIFRs. The viscosity of crystalloids was 1.07-1.12 mPa·s, and the viscosities of 6% hetastarch and 5% albumin were 2.59 times and 1.74 times that of normal saline, respectively. When the IIFR scales were preset to 20, 100, and 250 mL/hr, crystalloids were delivered at the preset flow rate within a difference of less than 10%, while 6% hetastarch was delivered at approximately 40% of the preset flow rates and 5% albumin was approximately 80% transmitted. When delivering colloids, IIFRs should be used with caution.

Influence of 3% Hypertonic Saline Versus 0.9% Saline on Intraoperative Maintenance Fluid Requirements in Adult Patients Undergoing Major Open Abdominal Surgeries: Randomized Controlled Study

BACKGROUND

Three percent hypertonic saline (3% HTS) acts like an osmotic buffer and draws fluid from the extracellular space into the intravascular compartment. Primary objective was to evaluate whether use of 3% HTS resulted in a difference in intraoperative maintenance fluid requirement versus 0.9% saline (NS). Secondary objectives were to evaluate differences in 24 h fluid requirements and safety of 3% HTS.

METHODS

Adult patients of either sex, 18-65 years, undergoing elective major open abdominal surgeries were randomized to receive infusions of 3% HTS or NS at 1 ml/kg/hr through large bore peripheral i.v cannulas, or central venous catheters after anesthesia induction. Intraoperative maintenance fluids were administered to maintain mean arterial pressure (≥70 mmHg), urine output (≥0.5 ml/kg/hr) and central venous pressure of 8-10 cm H₂O.

RESULTS

Ninety-three patients completed the study (46 in 3% HTS and 47 in NS group). No difference was seen in the volume of intraoperative maintenance fluids (3% HTS vs NS; 2243.9 ± 896.7 ml vs 2093.6 ± 868.7 ml; P = 0.34). Similarly, the 24 h postoperative fluid requirement was not different (3% HTS vs NS; 2006.6 ± 398.6 ml vs 2018.3 ± 389.3 ml; P = 0.94). Patients in 3% HTS group had statistically but not clinically significant higher serum sodium values at postoperative 12th and 24 h. No complication like thrombophlebitis or tissue ischemia was reported due to administration of 3% HTS through peripheral lines.

CONCLUSION

Administration of 3% HTS did not reduce intraoperative maintenance fluid requirements in patients undergoing major open abdominal surgeries.

TRIAL REGISTRATION

CTRI/2019/09/021032.

Enhanced recovery after surgery for major orthopedic surgery: a narrative review

Background

With increasing interest in enhanced recovery after surgery (ERAS), the literature on ERAS in orthopedic surgery is also rapidly accumulating. This review article aims to (1) summarize the components of the ERAS protocol applied to orthopedic surgery, (2) evaluate the outcomes of ERAS in orthopedic surgery, and (3) suggest practical strategies to implement the ERAS protocol successfully.

Main body

Overall, 17 components constituting the highly recommended ERAS protocol in orthopedic surgery were identified. In the preadmission period, preadmission counseling and the optimization of medical conditions were identified. In the preoperative period, avoidance of prolonged fasting, multimodal analgesia, and prevention of postoperative nausea and vomiting were identified. During the intraoperative period, anesthetic protocols, prevention of hypothermia, and fluid management, urinary catheterization, antimicrobial prophylaxis, blood conservation, local infiltration analgesia and local nerve block, and surgical factors were identified. In the postoperative period, early oral nutrition, thromboembolism prophylaxis, early mobilization, and discharge planning were identified. ERAS in orthopedic surgery reduced postoperative complications, hospital stay, and cost, and improved the patient outcomes and satisfaction with accelerated recovery. For successful implementation of the ERAS protocol, various strategies including the standardization of care system, multidisciplinary communication and collaboration, ERAS education, and continuous audit system are necessary.

Conclusion

The ERAS pathway enhanced patient recovery with a shortened length of stay, reduced postoperative complications, and improved patient outcomes and satisfaction. However, despite the significant progress in ERAS implementation in recent years, it has mainly focused on major surgeries such as arthroplasty. Therefore, further efforts to apply, audit, and optimize ERAS in various orthopedic surgeries are necessary.

Perioperative fluid administration and complications in emergency gastrointestinal surgery-an observational study

BACKGROUND

The fluid balance associated with a better outcome following emergency surgery is unknown. The aim of this study was to explore the association of the perioperative fluid balance and postoperative complications during emergency gastrointestinal surgery.

METHODS

We retrospectively included patients undergoing emergency surgery for gastrointestinal obstruction or perforation. A perioperative fluid balance of 2.5 L divided the cohort in a conservative and liberal group. Outcome was Clavien-Dindo graded complications registered 90 days postoperatively. We used logistic regression adjusted for age, sex, American Society of Anesthesiologists' classification, use of epidural analgesia, use of vasopressor, type of surgery, intraabdominal pathology, and hospital. Predicted risk of complications was demonstrated on a continuous scale of the fluid balance.

RESULTS

We included 342 patients operated between July 2014 and July 2015 from three centers. The perioperative fluid balance was 1.6 L IQR [1.0 to 2.0] in the conservative vs. 3.6 L IQR [3.0 to 5.3] in the liberal group. Odds ratio of overall 2.6 (95% CI 1.5 to 4.4), p < 0.001, and cardiopulmonary complications 3.2 (95% CI 1.9 to 5.7), p < 0.001, were increased in the liberal group. A perioperative fluid balance of 0-2 L was associated with minimal risk of cardiopulmonary complications compared to 1.5-3.5 L for renal complications.

CONCLUSION

We found a perioperative fluid balance above 2.5 L to be associated with an increased risk of overall and cardiopulmonary complications following emergency surgery for gastrointestinal obstruction or perforation. A perioperative fluid balance of 0-2 L was associated with the lowest risk of cardiopulmonary complications and 1.5-3.5 L for renal complications.

Intraoperative fluid management and kidney transplantation outcomes: A retrospective cohort study

BACKGROUND

Patients undergoing kidney transplantation traditionally receive liberal amounts of fluid during surgery. However, excessive fluids can lead to fluid overload and ileus. In this retrospective cohort study, we compared the effect of restrictive versus liberal fluid therapy on kidney transplantation outcomes.

METHODS

Patients who underwent deceased-donor kidney transplantation at Mayo Clinic from January 2014 to March 2019 were included. Those who received <3 L of intravenous fluids intraoperatively were categorized as "restrictive;" those who received ≥3 L were categorized as "liberal." The primary outcome was incidence of delayed graft function (DGF). Secondary outcomes included length of stay, readmission within 30 days, time to return of bowel function, and incidence of postoperative complications.

RESULTS

Of the 1171 patients included, 557 were in the restrictive group and 614 in the liberal group. The mean (SD) fluid intake was 2.17 (.54) L in the restrictive group and 3.67 (.68) L in the liberal group (P<.001). There was no difference in DGF (relative risk, 1.03; P = .56), length of stay (P = .34), readmission (P = .80), return of bowel function (P = .71), or other postoperative complications.

CONCLUSIONS

Intraoperative restrictive fluid therapy during kidney transplantation was not associated with DGF or worse outcomes when compared with liberal fluid therapy.

A Multicenter, Open-Label, Randomized Controlled Trial of a Conservative Fluid Management Strategy Compared With Usual Care in Participants After Cardiac Surgery: The Fluids After Bypass Study

OBJECTIVES

There is little evidence to guide fluid administration to patients admitted to the ICU following cardiac surgery. This study aimed to determine if a protocolized strategy known to reduce fluid administration when compared with usual care reduced ICU length of stay following cardiac surgery.

DESIGN

Prospective, multicenter, parallel-group, randomized clinical trial.

SETTING

Five cardiac surgical centers in New Zealand conducted from November 2016 to December 2018 with final follow-up completed in July 2019.

PATIENTS

Seven-hundred fifteen patients undergoing cardiac surgery; 358 intervention and 357 usual care.

INTERVENTIONS

Randomization to protocol-guided strategy utilizing stroke volume variation to guide administration of bolus fluid or usual care fluid administration until desedation or up to 24 hours. Primary outcome was length of stay in ICU. Organ dysfunction, mortality, process of care measures, patient-reported quality of life, and disability-free survival were collected up to day 180.

MEASUREMENTS AND MAIN RESULTS

Overall 666 of 715 (93.1%) received at least one fluid bolus. Patients in the intervention group received less bolus fluid (median [interquartile range], 1,000 mL [250-2,000 mL] vs 1,500 mL [500-2,500 mL]; p < 0.0001) and had a lower overall fluid balance (median [interquartile range], 319 mL [-284 to 1,274 mL] vs 673 mL [38-1,641 mL]; p < 0.0001) in the intervention period. There was no difference in ICU length of stay between the two groups (27.9 hr [21.8-53.5 hr] vs 25.6 hr [21.9-64.6 hr]; p = 0.95). There were no differences seen in development of organ dysfunction, quality of life, or disability-free survival at any time points. Hospital mortality was higher in the intervention group (4% vs 1.4%; p = 0.04).

CONCLUSIONS

A protocol-guided strategy utilizing stroke volume variation to guide administration of bolus fluid when compared with usual care until desedation or up to 24 hours reduced the amount of fluid administered but did not reduce the length of stay in ICU.

Intraoperative crystalloid utilization variability and association with postoperative outcomes: A post hoc analysis of two multicenter prospective cohort studies

BACKGROUND

The optimal regimen for intravenous administration of intraoperative fluids remains unclear. Our goal was to analyze intraoperative crystalloid volume administration practices and their association with postoperative outcomes.

METHODS

We extracted clinical data from two multicenter observational studies including adult patients undergoing colorectal surgery and total hip (THA) and knee arthroplasty (TKA). We analyzed the distribution of intraoperative fluid administration. Regression was performed using a general linear model to determine factors predictive of fluid administration. Patient outcomes and intraoperative crystalloid utilization were summarized for each surgical cohort. Regression models were developed to evaluate associations of high or low intraoperative crystalloid with the likelihood of increased postoperative complications, mainly acute kidney injury (AKI) and hospital length of stay (LOS).

RESULTS

7580 patients were included. The average adjusted intraoperative crystalloid infusion rate across all surgeries was to 7.9 (SD 4) mL/kg/h. The regression model strongly favored the type of surgery over other patient predictors. We found that high fluid volume was associated with 40% greater odds ratio (OR 1.40; 95% confidence interval 1.01-1.95, p = 0.044) of postoperative complications in patients undergoing THA, while we found no associations for the other types of surgeries, AKI and LOS CONCLUSIONS: A wide variability was observed in intraoperative crystalloid volume administration; however, this did not affect postoperative outcomes.

Fluid management in patients undergoing neurosurgery

Fluid management is an important component of perioperative care for patients undergoing neurosurgery. The primary goal of fluid management in neurosurgery is the maintenance of normovolemia and prevention of serum osmolarity reduction. To maintain normovolemia, it is important to administer fluids in appropriate amounts following appropriate methods, and to prevent a decrease in serum osmolarity, the choice of fluid is essential. There is considerable debate about the choice and optimal amounts of fluids administered in the perioperative period. However, there is little high-quality clinical research on fluid therapy for patients undergoing neurosurgery. This review will discuss the choice and optimal amounts of fluids in neurosurgical patients based on the literature, recent issues, and perioperative fluid management practices.

Perioperative liberal versus restrictive fluid strategies and postoperative outcomes: a systematic review and metanalysis on randomised-controlled trials in major abdominal elective surgery

Background

Postoperative complications impact on early and long-term patients’ outcome. Appropriate perioperative fluid management is pivotal in this context; however, the most effective perioperative fluid management is still unclear. The enhanced recovery after surgery pathways recommend a perioperative zero-balance, whereas recent findings suggest a more liberal approach could be beneficial. We conducted this trial to address the impact of restrictive vs. liberal fluid approaches on overall postoperative complications and mortality.

Methods

Systematic review and meta-analysis, including randomised controlled trials (RCTs). We performed a systematic literature search using MEDLINE (via Ovid), EMBASE (via Ovid) and the Cochrane Controlled Clinical trials register databases, published from 1 January 2000 to 31 December 2019. We included RCTs enrolling adult patients undergoing elective abdominal surgery and comparing the use of restrictive/liberal approaches enrolling at least 15 patients in each subgroup. Studies involving cardiac, non-elective surgery, paediatric or obstetric surgeries were excluded.

Results

After full-text examination, the metanalysis finally included 18 studies and 5567 patients randomised to restrictive (2786 patients; 50.0%) or liberal approaches (2780 patients; 50.0%). We found no difference in the occurrence of severe postoperative complications between restrictive and liberal subgroups [risk difference (95% CI) = 0.009 (− 0.02; 0.04); p value = 0.62; I₂ (95% CI) = 38.6% (0–66.9%)]. This result was confirmed also in the subgroup of five studies having a low overall risk of bias. The liberal approach was associated with lower overall renal major events, as compared to the restrictive [risk difference (95% CI) = 0.06 (0.02–0.09); p value  = 0.001]. We found no difference in either early (p value  = 0.33) or late (p value  = 0.22) postoperative mortality between restrictive and liberal subgroups

Conclusions

In major abdominal elective surgery perioperative, the choice between liberal or restrictive approach did not affect overall major postoperative complications or mortality. In a subgroup analysis, a liberal as compared to a restrictive perioperative fluid policy was associated with lower overall complication renal major events, as compared to the restrictive.

Trial Registration

CRD42020218059; Registration: February 2020, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=218059.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03629-y.

Perioperative outcomes of goal-directed versus conventional fluid therapy in radical cystectomy with enhanced recovery protocol

PURPOSE

The aim of this study is to evaluate the intra/perioperative fluid management and early postoperative outcomes of patients who underwent radical cystectomy with Enhanced Recovery After Surgery protocol, using goal-directed fluid therapy compared to conventional fluid therapy.

METHODS

This cohort study included patients who underwent open RC for urothelial bladder carcinoma with intent to cure and Enhanced Recovery After Surgery protocol between May 2012 and August 2019. Patients who had palliative or salvage cystectomy and/or adjunct procedures, as well as those with missing detailed perioperative data were excluded. Data were compared between patients who received goal-directed fluid therapy using stroke volume variation by FloTrac™/Vigileo system (n = 119) and conventional fluid therapy based on the anesthesiologist discretion (n = 192). Primary outcome variable was 90-day complications and secondary outcome measures included in-hospital GFR trend, length of stay, and 90-day readmission.

RESULTS

The goal-directed fluid therapy group received less total and net intra/perioperative fluid, yet early postoperative glomerular filtration rate trends were similar between both groups (p = 0.7). Estimated blood loss, blood transfusion, index hospital stay, 90-day complication and readmission rates were also comparable between the two groups. Multivariable logistic regression showed no significant association between perioperative fluid management method and 90-day complication rate (OR 1.4, 95% CI 0.8-2.4, p = 0.2).

CONCLUSION

Stroke volume variation guided goal-directed fluid therapy is safe in radical cystectomy without compromising the renal function. It is associated with less intra- and perioperative fluid infusion; however, no association with hospital stay, 90-day complication or readmission rates were noted.

Intraoperative crystalloid utilization variability and association with postoperative outcomes: A post hoc analysis of two multicenter prospective cohort studies

BACKGROUND

The optimal regimen for intravenous administration of intraoperative fluids remains unclear. Our goal was to analyze intraoperative crystalloid volume administration practices and their association with postoperative outcomes.

METHODS

We extracted clinical data from two multicenter observational studies including adult patients undergoing colorectal surgery and total hip (THA) and knee arthroplasty (TKA). We analyzed the distribution of intraoperative fluid administration. Regression was performed using a general linear model to determine factors predictive of fluid administration. Patient outcomes and intraoperative crystalloid utilization were summarized for each surgical cohort. Regression models were developed to evaluate associations of high or low intraoperative crystalloid with the likelihood of increased postoperative complications, mainly acute kidney injury (AKI) and hospital length of stay (LOS).

RESULTS

7,580 patients were included. The average adjusted intraoperative crystalloid infusion rate across all surgeries was to 7.9 (SD 4) mL/kg/h. The regression model strongly favored the type of surgery over other patient predictors. We found that high fluid volume was associated with 40% greater odds ratio (OR 1.40; 95% confidence interval1.01-1.95, p = 0.044) of postoperative complications in patients undergoing THA, while we found no associations for the other types of surgeries, AKI and LOS CONCLUSIONS: A wide variability was observed in intraoperative crystalloid volume administration; however, this did not affect postoperative outcomes.

[Enhanced recovery after surgery (ERAS): less is more : What must be considered from an anesthesiological perspective?]

BACKGROUND

Enhanced recovery after surgery (ERAS) is a multidisciplinary treatment model with the aim of guaranteeing a reduction of postoperative complications by the maintenance or early restoration of the patient-specific homoeostasis. From the anesthesiologist's perspective in all three areas of the perioperative phases there are important aspects that need to be addressed in the sense of a holistic treatment concept in order to achieve the highest possible benefit for the patient.

OBJECTIVE

In the perioperative period there is a bundle of anesthesiological measures, which make the ERAS concept into what it is now. At this point the focus is on the preoperative preparation and optimization of the patient and on the intraoperative and postoperative fluid management.

MATERIAL AND METHODS

A selective literature search was carried out in the Medline and Cochrane Library databases including consideration of national and international guidelines.

RESULTS

From an anesthesiological perspective there are relevant aspects in all three pillars of the perioperative phase, the adherence of which will improve the outcome of the patient: a comprehensive risk evaluation in the preoperative period and the avoidance of any sedative drugs; intraoperative individualized fluid management in the sense of a target-oriented optimization; early postoperative enteral nutrition and the avoidance of intravenous fluid administration, whenever justifiable.

CONCLUSION

Implementing the ERAS concept in the daily clinical routine in combination with maintaining a high compliance with the protocols is a demanding interdisciplinary challenge that urgently needs to be continued.

Terms, Definitions, Nomenclature, and Routes of Fluid Administration

Fluid therapy is administered to veterinary patients in order to improve hemodynamics, replace deficits, and maintain hydration. The gradual expansion of medical knowledge and research in this field has led to a proliferation of terms related to fluid products, fluid delivery and body fluid distribution. Consistency in the use of terminology enables precise and effective communication in clinical and research settings. This article provides an alphabetical glossary of important terms and common definitions in the human and veterinary literature. It also summarizes the common routes of fluid administration in small and large animal species.

Effects of Liberal Versus Restrictive Fluid Therapy on Renal Function Indices in Laparoscopic Bariatric Surgery

Background

Earlier studies have suggested the liberal administration of fluids in favor of reducing the risk of rhabdomyolysis in obese patients, but the results are conflicting.

Objectives

The present study aimed at comparing the effects of liberal and restrictive fluid therapy on renal indices in laparoscopic gastric bypass surgery.

Methods

In a double-blinded randomized clinical trial, 72 candidates of bariatric surgery were randomly assigned into two groups of restrictive and liberal fluid therapy. Indices, including BUN, creatinine, creatine kinase, GFR, and urine output were measured before and 24 hours after the surgery. The clinical trial was registered at IRCT.ir under code IRCT20170109031852N3.

Results

There was no significant difference in BUN, creatinine, creatinine kinase, and GFR indices between the two groups of liberal and restrictive fluid therapy both before and 24 hours after surgery (P > 0.05). Intragroup comparisons before and after surgery revealed that BUN decreased in both groups after the surgery (P < 0.05). Also, creatinine and GFR values improved in patients who received a liberal fluid regimen, whereas these indices remained statistically unchanged in the restrictive group before and 24 hours after the surgery (P > 0.05).

Conclusions

Two methods of liberal and restrictive fluid therapy have comparable effects on traditional renal functional indices in laparoscopic bariatric surgery. The clinical significance of observed differences in outcomes should be investigated in further studies. The use of early biomarkers of acute kidney injury is warranted.

The cardiac output optimisation following liver transplant (COLT) trial: a feasibility randomised controlled trial

BACKGROUND

Perioperative goal directed fluid therapy (GDFT) has been shown to reduce postoperative complications following major surgery; this intervention has not been formally evaluated in the setting of liver transplantation.

METHODS

We conducted a prospective trial of GDFT following liver transplantation randomising patients with liver cirrhosis to either 12 h of GDFT using non-invasive cardiac output monitoring or standard care (SC). The primary outcome was feasibility. Secondary outcomes included survival, postoperative complications (Clavien-Dindo), quality of life (by EQ-5D-5L) and resource use. Trial specific follow up occurred at 90 and 180 days after surgery.

RESULTS

The study was feasible. Of 224 eligible patients, 122 were approached, 114 consented to participate and 60 were enrolled into the trial. The mean (SD) volume of IV crystalloid administered to the GDFT group during the 12-h study period was 3968 (2073) ml for the GDFT group and 2510 (1026) ml for the SC group. As regards secondary outcomes there was no difference in survival or overall complication rates. There was no significant difference in quality of life scores and resource use between the groups.

CONCLUSION

A randomised study of GDFT following liver transplantation is feasible. A post-trial stakeholder meeting supported proceeding with a full multi-centre trial.

Delayed remnant kidney function recovery is less observed in living donors who receive an analgesic, intrathecal morphine block in laparoscopic nephrectomy for kidney transplantation: a propensity score-matched analysis

BACKGROUND

This study analyzed remnant kidney function recovery in living donors after laparoscopic nephrectomy to establish a risk stratification model for delayed recovery and further investigated clinically modifiable factors.

PATIENTS AND METHODS

This retrospective study included 366 adult living donors who underwent elective donation surgery between January 2017 and November 2019 at our hospital. ITMB was included as an analgesic component in the living donor strategy for early postoperative pain relief from November 2018 to November 2019 (n = 116). Kidney function was quantified based on the estimated glomerular filtration rate (eGFR), and delayed functional recovery of remnant kidney was defined as eGFR < 60 mL/min/1.73 m² on postoperative day (POD) 1 (n = 240).

RESULTS

Multivariable analyses revealed that lower risk for development of eGFR < 60 mL/min/1.73 m² on POD 1 was associated with ITMB, female sex, younger age, and higher amount of hourly fluid infusion (area under the receiver operating characteristic curve = 0.783; 95% confidence interval = 0.734-0.832; p < 0.001). Propensity score (PS)-matching analyses showed that prevalence rates of eGFR < 60 mL/min/1.73 m² on PODs 1 and 7 were higher in the non-ITMB group than in the ITMB group. ITMB adjusted for PS was significantly associated with lower risk for development of eGFR < 60 mL/min/1.73 m² on POD 1 in PS-matched living donors. No living donors exhibited severe remnant kidney dysfunction and/or required renal replacement therapy at POD 7.

CONCLUSIONS

We found an association between the analgesic impact of ITMB and better functional recovery of remnant kidney in living kidney donors. In addition, we propose a stratification model that predicts delayed functional recovery of remnant kidney in living donors: male sex, older age, non-ITMB, and lower hourly fluid infusion rate.

The James A. Rand Young Investigator's Award: Traditional Intravenous Fluid vs. Oral Fluid Administration in Primary Total Knee Arthroplasty: A Randomized Trial

BACKGROUND

Optimal perioperative fluid management has not been established in patients undergoing orthopedic surgical procedures. Our purpose was to investigate the effects of perioperative fluid management (ie, preoperative, intraoperative, and postoperative) on patients undergoing total knee arthroplasty (TKA).

METHODS

One hundred thirty patients who met inclusion criteria undergoing primary unilateral TKA were prospectively randomized into traditional (TFG) vs oral (OFG) perioperative fluid management groups. The primary outcome was change in body weight (BW). Secondary outcome measures included knee motion, leg girth, bioelectrical impendence, quadriceps activation, functional outcomes testing, Knee injury and Osteoarthritis Outcome Score JR, VR-12, laboratory values, vital signs, patient satisfaction, pain scores, and adverse events.

RESULTS

The TFG had increased BW the evening of surgery (7.0 ± 4.3 vs 3.0 ± 3.9, P < .0001), postoperative day (POD) #1 (9.1 ± 4.3 vs 4.7 ± 3.9, P < .0001), and POD #2 (6.2 ± 5.0 vs 4.4 ± 4.0, P = .032). Bioelectrical impedance showed less limb edema in the OFG (4.2 ± 29.7 vs 17.8 ± 30.3, P < .0001) on POD #1. Urine specific gravity differences were seen preoperatively between groups (OFG, more hydrated, P = .002). Systolic blood pressure decrease from the baseline was greater in the OFG on arrival to the floor (19.4 ± 13.5 vs 10.6 ± 12.8, P < .0001) and 8 (23.4 ± 13.3 vs 17.0 ± 12.9, P = .006) and 16 (25.8 ± 13.8 vs 25.8 ± 13.8, P = .046) hours after floor arrival. The TFG had more urine output on POD #1 (3369 mL ± 1343 mL vs 2435 mL ± 1151 mL, P < .0001). The OFG were more likely to go home on POD #1 than the TFG (63 vs 56, P = .02).

CONCLUSION

Oral fluid intake with IVF restriction in the perioperative period after TKA may offer short-term benefits with swelling and BW fluctuations. The authors continue to limit perioperative IVFs and encourage patient initiated fluid intake.

[Meta-analyses on measurement precision of non-invasive hemodynamic monitoring technologies in adults]

An ideal non-invasive monitoring system should provide accurate and reproducible measurements of clinically relevant variables that enables clinicians to guide therapy accordingly. The monitor should be rapid, easy to use, readily available at the bedside, operator-independent, cost-effective and should have a minimal risk and side effect profile for patients. An example is the introduction of pulse oximetry, which has become established for non-invasive monitoring of oxygenation worldwide. A corresponding non-invasive monitoring of hemodynamics and perfusion could optimize the anesthesiological treatment to the needs in individual cases. In recent years several non-invasive technologies to monitor hemodynamics in the perioperative setting have been introduced: suprasternal Doppler ultrasound, modified windkessel function, pulse wave transit time, radial artery tonometry, thoracic bioimpedance, endotracheal bioimpedance, bioreactance, and partial CO₂ rebreathing have been tested for monitoring cardiac output or stroke volume. The photoelectric finger blood volume clamp technique and respiratory variation of the plethysmography curve have been assessed for monitoring fluid responsiveness. In this manuscript meta-analyses of non-invasive monitoring technologies were performed when non-invasive monitoring technology and reference technology were comparable. The primary evaluation criterion for all studies screened was a Bland-Altman analysis. Experimental and pediatric studies were excluded, as were all studies without a non-invasive monitoring technique or studies without evaluation of cardiac output/stroke volume or fluid responsiveness. Most studies found an acceptable bias with wide limits of agreement. Thus, most non-invasive hemodynamic monitoring technologies cannot be considered to be equivalent to the respective reference method. Studies testing the impact of non-invasive hemodynamic monitoring technologies as a trend evaluation on outcome, as well as studies evaluating alternatives to the finger for capturing the raw signals for hemodynamic assessment, and, finally, studies evaluating technologies based on a flow time measurement are current topics of clinical research.

Pharmacist intervention to enhance postoperative fluid prescribing practice in an Iraqi hospital through implementation of NICE guideline

Objective:

The objectives of this study were to evaluate the current practice of postoperative fluid prescribing and assess the effectiveness of pharmacist-led intervention in the implementation of the National Institute of Health and Care Excellence (NICE) fluid therapy guideline in an Iraqi hospital.

Methods:

The prospective interventional study was conducted at AL-Hilla Teaching Hospital, Babylon, Iraq between November 2017 and July 2018. The study included two phases: The pre-intervention phase with 84 patients and the post-intervention phase with 112 patients. A pharmacist provided training and educational sessions for the hospital physicians and pharmacists about the NICE guideline of fluid therapy. The researcher calculated the amount of given post-operative fluids and compared to the NICE guideline and also measured the patients’ body weight, serum Na, K and creatinine pre-and post-operatively.

Results:

The pre-intervention phase showed no correlation between the amounts of prescribed fluids and body weight which caused increases in patients’ body weight. In pre-intervention phase, 6% of patients experienced hyponatremia, 19% had hypernatremia and 7.1% had hypokalemia. In the post-intervention phase, abnormal level of electrolytes and patient weight gain decreased significantly. Additionally, the intervention led to a strong correlation between body weight and amount of prescribed fluids in addition to lowering the incidence of electrolyte disturbances.

Conclusions:

A high proportion of patients in the pre-intervention phase experienced fluid overload, weight gain and electrolyte disturbances when fluid therapy was not prescribed in accordance with the NICE guidelines. The pharmacist-led intervention increased the surgeon awareness of the proper use of the NICE guideline which decreased the incidence of fluid-related complications and the inconsistency of fluid prescribing. Pharmacists can play a critical role to enhance post-operative fluid prescribing and minimize fluid-induced complications.

Early Acute Kidney Injury Within an Established Enhanced Recovery Pathway: Uncommon and Transitory

BACKGROUND

The present study aimed to assess the impact of perioperative fluid management on early acute kidney injury (AKI) rate and long-term sequelae in patients undergoing elective colorectal procedures within an enhanced recovery pathway (ERP).

METHODS

Retrospective analysis of consecutive patients from a prospectively maintained ERP database (2011-2015) is performed. Pre- and postoperative creatinine levels (within 24 h) were compared according to risk (preoperative creatinine rise ×1.5), injury (×2), failure (×3), loss of kidney function and end-stage kidney disease (RIFLE) criteria. Risk factors for early AKI were identified through logistic regression analysis, and long-term outcome in patients with AKI was assessed.

RESULTS

Out of 7103 patients, 4096 patients (58%) with pre- and postoperative creatinine levels were included. Of these, 104 patients (2.5%) presented postoperative AKI. AKI patients received higher amounts of POD 0 fluids (3.8 ± 2.4 vs. 3.2 ± 2 L, p = 0.01) and had increased postoperative weight gain at POD 2 (6 ± 4.9 vs. 3 ± 2.7 kg, p = 0.007). Independent risk factors for AKI were high ASA score (ASA ≥ 3: OR 1.7; 95% CI 1.1-2.5), prolonged operating time (>180 min: OR 1.9; 95% CI 1.3-2.9) and diabetes mellitus (OR 2.5; 95% CI 1.5-4), while minimally invasive surgery was a protective factor (OR 0.6; 95% CI 0.4-0.9). Five patients (0.1%) developed chronic kidney disease, and two of them needed dialysis after a mean follow-up of 33.7 ± 22.4 months.

CONCLUSIONS

Early AKI was very uncommon in the present cohort of colorectal surgery patients treated within an ERP, and long-term sequelae were exceptionally low.

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.

PERioperative Fluid Management in Elective ColecTomy (PERFECT)-a national prospective cohort study

BACKGROUND

There is contradictory evidence regarding the merits of restricted versus liberal perioperative intravenous (IV) fluid administration in bowel surgery. This study sought to audit perioperative fluid management in elective colectomy in Ireland and to analyse the impact of such on operative outcomes.

METHODS

A national surgical trainee collaborative audit of perioperative fluid management was performed. Data from each site was collected prospectively over a selected 3-week period within a pre-defined 2-month block. Collected variables included demographics, type of operation/anaesthethic, volume/type of fluid administration pre-, intra- and post-operatively, 30-day morbidity and mortality. Primary outcome was fluid balance 24-h post-operatively with further analysis to identify the impact of this on 30-day morbidity. ROC curves were generated to identify the critical volume at which fluid balance was associated with 30-day morbidity.

RESULTS

Ninety-four patients were enrolled from 17 hospitals. Mean age was 64 years. A total of 48.9% (N = 46) were managed by ERAS and 51.1% (N = 48) received bowel preparation. Almost 70% of cases (N = 63) were completed by minimally invasive techniques. Significant 30-day morbidity requiring hospital readmission was low [6.4% (n = 6)]. Median fluid balance at 24 h was + 715 ml (IQR 165-1486 ml). On multivariate analysis, high BMI (p = 0.02), indication for surgery (p = 0.02) and critical care admission (p = 0.008) were significantly predictive of 30-day morbidity. Twenty-four hour fluid balance >+ 665 ml was associated with increased risk of 30-day morbidity on univariate but not multivariate analysis, implying association but not causation.

CONCLUSION

Overall, perioperative fluid management was within an acceptable range with minimal impact on 30-day morbidity following elective colorectal surgery.

Enhanced recovery after surgery protocol enhances early postoperative recovery after pancreaticoduodenectomy

BACKGROUND

Enhanced recovery after surgery (ERAS) protocol is a multimodal, multidisciplinary and evidence-based approach to reduce surgical stress and enhance recovery in the postoperative period. This study aimed to analyze the outcome of ERAS protocol in patients after pancreaticoduodenectomy (PD).

METHODS

A total of 50 consecutive patients with pancreatic/periampullary cancer who underwent PD between January 2016 to August 2017 were included in the study. As per the institute ERAS protocol, nasogastric tube (NGT) was removed on postoperative day (POD) 1 if output was less than 200 mL and oral sips were allowed; oral liquids were allowed on POD2; semisolid diet by POD3; abdominal drain was removed on POD 4 if output was less than 100 mL with no evidence of postoperative pancreatic fistula (POPF); normal diet was allowed on POD5. Discharge criteria on POD6 were afebrile, tolerating oral normal diet, pain free and no surgery related complications (defined as per the ISGPS definitions).

RESULTS

NGT was removed on POD1 in 45 (90%) patients, abdominal drain removed by POD4 in 41 (82%) and 43 (86%) patients were discharged on POD6. There was no 30-day postoperative mortality. Three (6%) patients had delayed gastric emptying (DGE). None had postoperative hemorrhage and POPF. Readmission rate was 8%. A significant relation was found between the length of hospital stay (LOS) with age (P < 0.05) and a marginal relation between LOS and postoperative albumin (P = 0.05).

CONCLUSIONS

ERAS protocol can be safely followed in the perioperative care of patients who undergo PD. Early removal of NGT and allowing oral diet restore bowel function early. ERAS decreases the LOS and postoperative complications.

The impact of intraoperative fluid management during laparoscopic donor nephrectomy on donor and recipient outcomes

BACKGROUND

Intraoperative fluid management during laparoscopic donor nephrectomy (LDN) may have a significant effect on donor and recipient outcomes. We sought to quantify variability in fluid management and investigate its impact on donor and recipient outcomes.

METHODS

A retrospective review of patients who underwent LDN from July 2011 to January 2016 with paired kidney recipients at a single center was performed. Patients were divided into tertiles of intraoperative fluid management (standard, high, and aggressive). Donor and recipient demographics, intraoperative data, and postoperative outcomes were analyzed.

RESULTS

Overall, 413 paired kidney donors and recipients were identified. Intraoperative fluid management (mL/h) was highly variable with no correlation to donor weight (kg) (R = 0.017). The aggressive fluid management group had significantly lower recipient creatinine levels on postoperative day 1. However, no significant differences were noted in creatinine levels out to 6 months between groups. No significant differences were noted in recipient postoperative complications, graft loss, and death. There was a significant increase (P < 0.01) in the number of total donor complications in the aggressive fluid management group.

CONCLUSIONS

Aggressive fluid management during LDN does not improve recipient outcomes and may worsen donor outcomes compared to standard fluid management.

Calculated plasma volume status and outcomes in patients undergoing coronary bypass graft surgery

OBJECTIVES

Congestion is associated with worse outcomes in critically ill surgical patients but can be difficult to quantify noninvasively. We hypothesised that plasma volume status (PVS), estimated preoperatively using a validated formula that enumerates percentage change from ideal plasma volume (PV), would provide incremental prognostic utility after coronary artery bypass graft (CABG) surgery.

METHODS

In this retrospective cohort study, patients who underwent CABG surgery (1999-2010) were identified from a prospectively collected database. Actual ([1-haematocrit] x [a+(b x weight [kg])]) and ideal (c x weight [kg]) PV were obtained from equations where a, b and c are sex-dependent constants. Calculated PVS was then derived (100% x [(actual-ideal)/ideal]).

RESULTS

In 1887 patients (mean age 67±10 years; 79% male; median European System for Cardiac Operative Risk Evaluation [EuroSCORE] 4), mean PVS was -8.2±9%. While 8% of subjects had clinical evidence of congestion, a relatively increased PV (PVS >0%) was estimated in 17% and correlated with lower serum sodium, higher EuroSCORE and a diagnosis of diabetes mellitus. A PVS≥5.6% was optimally prognostic and associated with greater mortality (HR: 2.31, p=0.009), independently of, and incremental to, EuroSCORE, New York Heart Association class and serum sodium. A PVS≥5.6% also independently predicted longer intensive care (β: 0.65, p=0.007) and hospital (β: 2.01, p=0.006) stays, and greater postoperative renal (OR: 1.61, p=0.008) and arrhythmic (OR: 1.29, p=0.03) complications.

CONCLUSIONS

Higher PVS values, calculated simply from weight and haematocrit, are associated with worse inpatient outcomes after CABG. PVS could help refine risk stratification and further investigations are warranted to evaluate the potential clinical utility of PVS-guided management in patients undergoing CABG.

Are we close to the ideal intravenous fluid?

The approach to i.v. fluid therapy for hypovolaemia may significantly influence outcomes for patients who experience a systemic inflammatory response after sepsis, trauma, or major surgery. Currently, there is no single i.v. fluid agent that meets all the criteria for the ideal treatment for hypovolaemia. The physician must choose the best available agent(s) for each patient, and then decide when and how much to administer. Findings from large randomized trials suggest that some colloid-based fluids, particularly starch-based colloids, may be harmful in some situations, but it is unclear whether they should be withdrawn from use completely. Meanwhile, crystalloid fluids, such as saline 0.9% and Ringer's lactate, are more frequently used, but debate continues over which preparation is preferable. Perhaps most importantly, it remains unclear how to select the optimal dose of fluid in different patients and different clinical scenarios. There is good reason to believe that both inadequate and excessive i.v. fluid administration may lead to poor outcomes, including increased risk of infection and organ dysfunction, for hypovolaemic patients. In this review, we summarize the current knowledge on this topic and identify some key pitfalls and some areas of agreed best practice.

Quest for the holy grail: Assessment of echo-derived dynamic parameters as predictors of fluid responsiveness in patients with acute aneurysmal subarachnoid hemorrhage

Background:

Acute aneurysmal subarachnoid hemorrhage (aSAH) is a potentially devastating event often presenting with a plethora of hemodynamic fluctuations requiring meticulous fluid management. The aim of this study was to assess the utility of newer dynamic predictors of fluid responsiveness such as Delta down (DD), superior vena cava collapsibility index (SVCCI), and aortic velocity time integral variability (VTIAoV) in patients with SAH undergoing neurosurgery.

Materials and Methods:

Fifteen individuals with SAH undergoing surgery for intracranial aneurysmal clipping were enrolled in this prospective study. Postinduction, vitals, anesthetic parameters, and the study variables were recorded as the baseline. Following this, patients received a fluid bolus of 10 ml/kg of colloid over 20 min, and measurements were repeated postfluid loading. Continuous variables were expressed as mean ± standard deviation and compared using Student's t-test, with a P < 0.05 considered statistically significant. The predictive ability of variables for fluid responsiveness was determined using Pearson's coefficient analysis (r).

Results:

There were 12 volume responders and 3 nonresponders (NR). DD >5 mm Hg was efficient in differentiating the responders from NR (P < 0.05) with a sensitivity and specificity of 90% and 85%, respectively, with a good predictive ability to identify fluid responders and NR; r = 0.716. SVCCI of >38% was 100% sensitive and 95% specific in detecting the volume status and in differentiating the responders from NR (P < 0.05) and is an excellent predictor of fluid responsive status; r = 0.906. VTIAoV >20% too proved to be a good predictor of fluid responsiveness, with a sensitivity and specificity of 100% and 90%, respectively, with a predictive power; r = 0.732.

Conclusion:

Our study showed that 80% of patients presenting with aSAH for intracranial aneurysm clipping were fluid responders with normal hemodynamic parameters such as heart rate and blood pressure. Among the variables, SVCCI >38% appears to be an excellent predictor followed by VTIAoV >20% and DD >5 mmHg in assessing the fluid status in this population.

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 .).

Early negative fluid balance is associated with lower mortality after cardiovascular surgery

BACKGROUND

Early fluid expansion could prevent postoperative organ hypoperfusion. However, excessive fluid resuscitation adversely influences multiple organ systems. This retrospective, observational study aimed to investigate the relationship between early negative fluid balance and postoperative mortality in critically ill adult patients following cardiovascular surgery.

METHODS

In total, 567 critically ill patients who had undergone cardiovascular surgery and whose intensive care unit length of stay (LOS) was more than 24 hours were enrolled. The baseline characteristics, daily fluid balance and cumulative fluid balance were obtained. Patients were followed until discharge or day 28. Multivariate logistic regressions adjusted by propensity score were used to analyze the relationship between early negative fluid balance and postoperative mortality.

RESULTS

Overall, postoperative mortality was 6.2% (35/567). Acute Physiology and Chronic Health Evaluation II on admission (odd ratios [OR] 1.110), acute kidney injury stage (OR 1.639) and renal replacement therapy received (OR 3.922) were the independent risk factors of postoperative mortality, whereas negative daily fluid balance at day 2 (OR 0.411) was the protective factor. Patients with a negative daily fluid balance at day 2 had lower postoperative mortality (3.4% vs. 12.2% in the positive fluid balance group), lower acute kidney injury (AKI) stage, were less likely to receive renal replacement therapy (RRT) and experienced shorter hospital LOS compared with those with a daily positive fluid balance.

CONCLUSION

This retrospective, observational study indicates that early negative fluid balance is associated with lower postoperative mortality in critically ill patients following cardiovascular surgery. Further prospective, randomized trials are needed to prove the benefits from the restrictive fluid management strategy.