Poor Adoption of Hemodynamic Optimization During Major Surgery

Improving perioperative care in low-resource settings with goal-directed therapy: a narrative review

Perioperative Goal-Directed Therapy (PGDT) has significantly showed to decrease complications and risk of death in high-risk patients according to numerous meta-analyses. The main goal of PGDT is to individualize the therapy with fluids, inotropes, and vasopressors, during and after surgery, according to patients' needs in order to prevent organic dysfunction development. In this opinion paper we aimed to focus a discussion on possible alternatives to invasive hemodynamic monitoring in low resource settings.

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.

Comparison of Goal-Directed Fluid Therapy using LiDCOrapid System with Regular Fluid Therapy in Patients Undergoing Spine Surgery as a Randomised Clinical Trial

Background

Goal-directed fluid therapy (GDFT) is a new concept to describe the cardiac output (CO) and stroke volume variation to guide intravenous fluid administration during surgery. LiDCOrapid (LiDCO, Cardiac Sensor System, UK Company Regd 2736561, VAT Regd 672475708) is a minimally invasive monitor that estimates the responsiveness of CO versus fluid infusion. We intend to find whether GDFT using the LiDCOrapid system can decrease the volume of intraoperative fluid therapy and facilitate recovery in patients undergoing posterior fusion spine surgeries in comparison to regular fluid therapy.

Methods

This study is a randomised clinical trial, and the design was parallel. Inclusion criteria for participants in this study were patients with comorbidities such as diabetes mellitus, hypertension, and ischemic heart disease undergoing spine surgery; exclusion criteria were patients with irregular heart rhythm or severe valvular heart disease. Forty patients with a previous history of medical comorbidities undergoing spine surgery were randomly and evenly assigned to receive either LiDCOrapid guided fluid therapy or regular fluid therapy. The volume of infused fluid was the primary outcome. The amount of bleeding, number of patients who needed packed red blood cell transfusion, base deficit, urine output, days of hospital length of stay and intensive care unit (ICU) admission, and time needed to start eating solids were monitored as secondary outcomes.

Results

The volume of infused crystalloid and urinary output in the LiDCO group was significantly lower than that of the control group (p = .001). Base deficit at the end of surgery was significantly better in the LiDCO group (p < .001). The duration of hospital length of stay in the LiDCO group was significantly shorter (p = .027), but the duration of ICU admission was not significantly different between the two groups.

Conclusion

Goal-directed fluid therapy using the LiDCOrapid system reduced the volume of intraoperative fluid therapy.

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

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

Bioreactance-guided fluid therapy for excision of a giant brain tumor in an infant under general anesthesia: A case report and literature review

Pediatric patients are more likely to suffer from brain tumors. Surgical resection is often the optimal treatment. Perioperative management of pediatric brain tumor resection brings great challenges to anesthesiologists, especially for fluid therapy. In this case, the infant-patient was only 69-day-old, weighed 6 kg，but she was facing a gaint brain tumor (7.9 cm × 8.1 cm × 6.7 cm) excision. The infant was at great risks such as hemorrhagic shock, cerebral edema, pulmonary edema, congestive heart failure, coagulation dysfunction, etc. However, we tried to use the parameters obtained by bioreactance-based NICOM® device (Cheetah Medical) to guide the infant’s intraoperative fluid therapy, and successfully avoided these complications and achieved a good prognosis.

The Effect of Intraoperative Fluid Management According to Stroke Volume Variation on Postoperative Bowel Function Recovery in Colorectal Cancer Surgery

Stroke volume variation (SVV) has been used to predict fluid responsiveness; however, it remains unclear whether goal-directed fluid therapy using SVV contributes to bowel function recovery in abdominal surgery. This prospective randomized controlled trial aimed to compare bowel movement recovery in patients undergoing colon resection surgery between groups using traditional or SVV-based methods for intravenous fluid management. We collected data between March 2015 and July 2017. Bowel function recovery was analyzed based on the gas-passing time, sips of water time, and soft diet (SD) time. Finally, we analyzed data from 60 patients. There was no significant between-group difference in the patients’ characteristics. Compared with the control group (n = 30), the SVV group (n = 30) had a significantly higher colloid volume and lower crystalloid volume. Moreover, the gas-passing time (77.8 vs. 85.3 h, p = 0.034) and SD time (67.6 vs. 85.1 h, p < 0.001) were significantly faster in the SVV group than in the control group. Compared with the control group, the SVV group showed significantly lower scores of pain on a numeric rating scale and morphine equivalent doses during post-anesthetic care, at 24 postoperative hours, and at 48 postoperative hours. Our findings suggested that, compared with the control group, the SVV group showed a faster postoperative SD time, reduced acute postoperative pain intensity, and lower rescue analgesics. Therefore, SVV-based optimal fluid management is expected to potentially contribute to postoperative bowel function recovery in patients undergoing colon resection surgery.

Anesthetic Management Using Multiple Closed-loop Systems and Delayed Neurocognitive Recovery: A Randomized Controlled Trial

BACKGROUND

Cognitive changes after anesthesia and surgery represent a significant public health concern. We tested the hypothesis that, in patients 60 yr or older scheduled for noncardiac surgery, automated management of anesthetic depth, cardiac blood flow, and protective lung ventilation using three independent controllers would outperform manual control of these variables. Additionally, as a result of the improved management, patients in the automated group would experience less postoperative neurocognitive impairment compared to patients having standard, manually adjusted anesthesia.

METHODS

In this single-center, patient-and-evaluator-blinded, two-arm, parallel, randomized controlled, superiority study, 90 patients having noncardiac surgery under general anesthesia were randomly assigned to one of two groups. In the control group, anesthesia management was performed manually while in the closed-loop group, the titration of anesthesia, analgesia, fluids, and ventilation was performed by three independent controllers. The primary outcome was a change in a cognition score (the 30-item Montreal Cognitive Assessment) from preoperative values to those measures 1 week postsurgery. Secondary outcomes included a battery of neurocognitive tests completed at both 1 week and 3 months postsurgery as well as 30-day postsurgical outcomes.

RESULTS

Forty-three controls and 44 closed-loop patients were assessed for the primary outcome. There was a difference in the cognition score compared to baseline in the control group versus the closed-loop group 1 week postsurgery (-1 [-2 to 0] vs. 0 [-1 to 1]; difference 1 [95% CI, 0 to 3], P = 0.033). Patients in the closed-loop group spent less time during surgery with a Bispectral Index less than 40, had less end-tidal hypocapnia, and had a lower fluid balance compared to the control group.

CONCLUSIONS

Automated anesthetic management using the combination of three controllers outperforms manual control and may have an impact on delayed neurocognitive recovery. However, given the study design, it is not possible to determine the relative contribution of each controller on the cognition score.

Nurse and Physician Perceptions of Working With Goal-Directed Therapy in the Perioperative Period

PURPOSE

To explore nurse and physician perceptions of working with and collaborating about arterial wave analysis for goal-directed therapy to identify barriers and facilitators for use in anesthesia departments, postanesthesia care units, and intensive care units.

DESIGN

A qualitative study drawing on ethnographic principles in a field study using the technique of nonparticipating observation and semistructured interviews.

METHODS

Data collection occurred using semistructured interviews with nurses (n = 23) and physicians (n = 12) and field observations in three anesthetic departments. An inductive approach for content analysis was used.

FINDINGS

The results showed one overarching theme Interprofessional collaboration encourage and impede based on three categories: (1) interprofessional and professional challenges; (2) obtaining competencies; and (3) understanding optimal fluid treatment.

CONCLUSIONS

Several barriers identified related to interprofessional collaboration. Nurses and physicians were dependent on each other's skills and capabilities to use arterial wave analysis. Education of nurses and physicians is important to secure optimal use of goal-directed therapy.

Implementation of closed-loop-assisted intra-operative goal-directed fluid therapy during major abdominal surgery: A case-control study with propensity matching

BACKGROUND

Goal-directed fluid therapy (GDFT) has been associated with improved patient outcomes. However, implementation of GDFT protocols remains low despite growing published evidence and the recommendations of multiple regulatory bodies in Europe. We developed a closed-loop-assisted GDFT management system linked to a pulse contour monitor to assist anaesthesiologists in applying GDFT.

OBJECTIVE

To assess the impact of our closed-loop system in patients undergoing major abdominal surgery in an academic hospital without a GDFT programme.

DESIGN

A case-control study with propensity matching.

SETTING

Operating rooms, Erasme Hospital, Brussels.

PATIENTS

All patients who underwent elective open major abdominal surgery between January 2013 and December 2016.

INTERVENTION

Implementation of our closed-loop-assisted GDFT in April 2015.

METHODS

A total of 104 patients managed with closed-loop-assisted GDFT were paired with a historical cohort of 104 consecutive non-GDFT patients. The historical control group consisted of patients treated before the implementation of the closed-loop-system, and who did not receive GDFT. In the closed-loop group, the system delivered a baseline crystalloid infusion of 3 ml kg h and additional 100 ml fluid boluses of either a crystalloid or colloid for haemodynamic optimisation.

MAIN OUTCOME MEASURES

The primary outcome was intra-operative net fluid balance. Secondary outcomes were composite major postoperative complications, composite minor postoperative complications and hospital length of stay (LOS).

RESULTS

Baseline characteristics were similar in both groups. Patients in the closed-loop group had a lower net intra-operative fluid balance compared with the historical group (median interquartile range [IQR] 2.9 [1.6 to 4.4] vs. 6.2 [4.0 to 8.3] ml kg h; P < 0.001). Incidences of major and minor postoperative complications were lower (17 vs. 32%, P = 0.015 and 31 vs. 45%, P = 0.032, respectively) and hospital LOS shorter [median (IQR) 10 (6 to 15) vs. 12 (9 to 18) days, P = 0.022] in the closed-loop group.

CONCLUSION

Implementation of our closed-loop-assisted GDFT strategy resulted in a reduction in intra-operative net fluid balance, which was associated with reduced postoperative complications and shorter hospital LOS.

TRIAL REGISTRATION NUMBER

NCT02978430.

Goal-directed fluid therapy on laparoscopic colorectal surgery within enhanced recovery after surgery program

INTRODUCTION

Enhanced recovery after surgery protocols (ERAS) are used in peri-operative care to reduce the stress response to surgical aggression. As fluid overload has been associated with increased morbidity and delayed hospital discharge, a major aspect of this is fluid management. Intra-operative goal-directed fluid protocols have been shown to reduce post-operative complications, particularly in high risk patients.?.

OBJECTIVE

To compare 2fluid therapy models (zero-balance versus goal-directed fluid therapy) in patients who were scheduled for laparoscopic colorectal surgery within an ERAS program, recording the rate of complications such as surgical site infection, ileus, post-operative náusea and vomiting, and variability of the estimated glomerular filtration rate (eGFR).

MATERIALS AND METHODS

An observational, retrospective study was conducted including adults who were scheduled for elective laparoscopic colorectal surgery within an ERAS program, and to investigate the postoperative complication rate.

RESULTS

A total of 128 patients were included in this study; 43 (33.6%) in the zero-balance group and 85 (66.4%) in the goal-directed fluid therapy group. The total fluids administered was lower in the goal-directed fluid therapy group, as well as the incidence of post-operative complications (surgical site infection, anastomotic leak, ileus, and postoperative náusea and vomiting). No significant differences were found for length of stay, intra-operative urine output, and variability of the eGFR.?.

CONCLUSION

The results of this study show that by using a goal-directed fluid therapy algorithm, the total amount of fluids administered can be reduced, as well as obtaining a lower incidence of post-operative complications.

Nurses' Indications for Administration of Perioperative Intravenous Fluid Therapy-A Prospective, Descriptive, Single-Center Cohort Study

PURPOSE

To examine whether nurse anesthetists and postanesthesia nurses' administration of intravenous (IV) fluid therapy during surgery and in the postanesthesia care unit is based on evidence. Secondarily to investigate if providing indications for IV fluid administration changed nursing practice.

DESIGN

Prospective, descriptive, single-center study in Scandinavia comparing two cohorts.

METHODS

Descriptive, fluid volume, and type data were obtained in both cohorts. Cohort 1 (n = 126) was used as baseline data. In cohort 2 (n = 130), nurses recorded indications for type and volume of fluid therapy using a validated list. Analysis compared median volumes of crystalloid or colloid fluids of surgical types by cohort. Analysis compared frequency of given indication reasons for each IV fluid by surgical type.

FINDINGS

Basic static variables were chosen most frequently for indications of IV fluid needed for all surgeries except high-risk abdominal surgery where dynamic variables were more frequent. Signs and symptoms of inadequate tissue perfusion were only sparsely indicated. The volume of intraoperative crystalloid fluids was statistically different for patients with hip fracture surgery in cohort 2. Volumes of both colloid and crystalloid fluids were significantly higher for high-risk abdominal surgery in cohort 2.

CONCLUSIONS

Nurse anesthetists and nurses in the postanesthesia care unit rely more on basic static parameters than signs of inadequate tissue perfusion when they make decisions about fluid administration. The indications cited for fluid administered to high-risk abdominal surgery and hip fracture patients did not always fit guidelines. This indicates the need of a stronger intervention to change practice to follow evidence-based clinical guidelines.

New generation continuous cardiac output monitoring from carbon dioxide elimination

Background

There is continuing interest among clinicians in the potential for advanced hemodynamic monitoring and “goal directed” intravenous fluid administration guided by minimally-invasive cardiac output measurement to reduce complication rates in high risk patients undergoing major surgery. However, the adoption of the available technologies has been limited, due to cost, complexity and reliability of measurements provided. We review progress in the development of new generation methods for continuous non-invasive monitoring of cardiac output from measurement of carbon dioxide elimination in ventilated patients using the Differential Fick method.

Main text

The history and underlying theoretical basis are described, and its recent further development and implementation using modern generation anesthesia monitoring and delivery systems by two separate but parallel methods, termed “Capnotracking” and “Capnodynamics”. Both methods generate breath-by-breath hands-free cardiac output monitoring from changes in carbon dioxide elimination produced by automatic computerized modulation of respiratory rate delivered by an electronic ventilator. Extensive preclinical validation in animal models of hemodynamic instability, with implanted ultrasonic flow probes for gold standard reference measurements, shows this approach delivers reliable, continuous cardiac output measurement in real time. The accuracy and precision of measurement by the Capnodynamic method were maintained under a wide range of both hemodynamic and respiratory conditions, including inotropic stimulation, vasodilatation, hemorrhage, caval compression, alveolar lavage, changes in tidal volume and positive end-expiratory pressure, and hypercapnia, with only brief derangement observed in a model of lower body ischemia involving release of prolonged aortic occlusion by an intra-aortic balloon. Phase 2 testing of a Capnotracking system in patients undergoing cardiac surgery and liver transplantation has achieved a percentage error of agreement with thermodilution of +/− 38.7% across a wide range of hemodynamic states.

Conclusions

Progress in development of these technologies suggest that a robust, automated and reliable method of non-invasive cardiac output monitoring from capnography is close at hand for use in major surgery and critical care. The great advantage of this approach is that it can be fully integrated into the anesthesia machine and ventilator, using components that are already standard in modern anesthesia and intensive care workstations, and should be virtually hands-free and automatic.

Practical impact of a decision support for goal-directed fluid therapy on protocol adherence: a clinical implementation study in patients undergoing major abdominal surgery

The purpose of this study was to assess the effects of using a real time clinical decision-support system, "Assisted Fluid Management" (AFM), to guide goal-directed fluid therapy (GDFT) during major abdominal surgery. We compared a group of patients managed using the AFM system with a historical cohort of patients (control group) who had been managed using a manual GDFT strategy. Adherence to the protocol was defined as the relative intraoperative time spent with a stroke volume variation (SVV) < 13%. We hypothesised that patients in the AFM group would have more time during surgery with a SVV < 13% compared to the control group. All patients had a radial arterial line connected to a pulse contour analysis monitor and received a 2 ml/kg/h maintenance crystalloid infusion. Additional 250 ml crystalloid boluses were administered whenever measured SVV ≥ 13% in the control group, and when the software suggested a fluid bolus in the AFM group. We compared 46 AFM-guided patients to 38 controls. Patients in the AFM group spent significantly more time during surgery with a SVV < 13% compared to the control group (median 92% [82, 96] vs. 76% [54, 86]; P < 0.0005), and received less fluid overall (1775 ml [1225, 2425] vs. 2350 ml [1825, 3250]; P = 0.010). The incidence of postoperative complications was comparable in the two groups. Implementation of a decision support system for GDFT guidance resulted in a significantly longer period during surgery with a SVV < 13% with a reduced total amount of fluid administered. Trial registration: Clinical Trials.gov (NCT03141411).

Crystalloid versus Colloid for Intraoperative Goal-directed Fluid Therapy Using a Closed-loop System: A Randomized, Double-blinded, Controlled Trial in Major Abdominal Surgery

BACKGROUND

The type of fluid and volume regimen given intraoperatively both can impact patient outcome after major surgery. This two-arm, parallel, randomized controlled, double-blind, bi-center superiority study tested the hypothesis that when using closed-loop assisted goal-directed fluid therapy, balanced colloids are associated with fewer postoperative complications compared to balanced crystalloids in patients having major elective abdominal surgery.

METHODS

One hundred and sixty patients were enrolled in the protocol. All patients had maintenance-balanced crystalloid administration of 3 ml · kg · h. A closed-loop system delivered additional 100-ml fluid boluses (patients were randomized to receive either a balanced-crystalloid or colloid solution) according to a predefined goal-directed strategy, using a stroke volume and stroke volume variation monitor. All patients were included in the analysis. The primary outcome was the Post-Operative Morbidity Survey score, a nine-domain scale, at day 2 postsurgery. Secondary outcomes included all postoperative complications.

RESULTS

Patients randomized in the colloid group had a lower Post-Operative Morbidity Survey score (median [interquartile range] of 2 [1 to 3] vs. 3 [1 to 4], difference -1 [95% CI, -1 to 0]; P < 0.001) and a lower incidence of postoperative complications. Total volume of fluid administered intraoperatively and net fluid balance were significantly lower in the colloid group.

CONCLUSIONS

Under our study conditions, a colloid-based goal-directed fluid therapy was associated with fewer postoperative complications than a crystalloid one. This beneficial effect may be related to a lower intraoperative fluid balance when a balanced colloid was used. However, given the study design, the mechanism for the difference cannot be determined with certainty.

Goal-directed Fluid Therapy Does Not Reduce Primary Postoperative Ileus after Elective Laparoscopic Colorectal Surgery: A Randomized Controlled Trial

BACKGROUND

Inadequate perioperative fluid therapy impairs gastrointestinal function. Studies primarily evaluating the impact of goal-directed fluid therapy on primary postoperative ileus are missing. The objective of this study was to determine whether goal-directed fluid therapy reduces the incidence of primary postoperative ileus after laparoscopic colorectal surgery within an Enhanced Recovery After Surgery program.

METHODS

Randomized patient and assessor-blind controlled trial conducted in adult patients undergoing laparoscopic colorectal surgery within an Enhanced Recovery After Surgery program. Patients were assigned randomly to receive intraoperative goal-directed fluid therapy (goal-directed fluid therapy group) or fluid therapy based on traditional principles (control group). Primary postoperative ileus was the primary outcome.

RESULTS

One hundred twenty-eight patients were included and analyzed (goal-directed fluid therapy group: n = 64; control group: n = 64). The incidence of primary postoperative ileus was 22% in the goal-directed fluid therapy and 22% in the control group (relative risk, 1; 95% CI, 0.5 to 1.9; P = 1.00). Intraoperatively, patients in the goal-directed fluid therapy group received less intravenous fluids (mainly less crystalloids) but a greater volume of colloids. The increase of stroke volume and cardiac output was more pronounced and sustained in the goal-directed fluid therapy group. Length of hospital stay, 30-day postoperative morbidity, and mortality were not different.

CONCLUSIONS

Intraoperative goal-directed fluid therapy compared with fluid therapy based on traditional principles does not reduce primary postoperative ileus in patients undergoing laparoscopic colorectal surgery in the context of an Enhanced Recovery After Surgery program. Its previously demonstrated benefits might have been offset by advancements in perioperative care.

Goal directed fluid therapy decreases postoperative morbidity but not mortality in major non-cardiac surgery: a meta-analysis and trial sequential analysis of randomized controlled trials

BACKGROUND AND AIMS

Optimum perioperative fluid administration may improve postoperative outcome after major surgery. This meta-analysis and systematic review has been aimed to determine the effect of dynamic goal directed fluid therapy (GDFT) on postoperative morbidity and mortality in non-cardiac surgical patients.

MATERIAL AND METHODS

Meta-analysis of published prospective randomized controlled trials where GDFT based on non-invasive flow based hemodynamic measurement has been compared with a standard care. Data from 41 prospective randomized trials have been included in this study.

RESULTS

Use of GDFT in major surgical patients does not decrease postoperative hospital/30-day mortality (OR 0.70, 95 % CI 0.46-1.08, p = 0.11) length of post-operative hospital stay (SMD -0.14; 95 % CI -0.28, 0.00; p = 0.05) and length of ICU stay (SMD -0.12; 95 % CI -0.28, 0.04; p = 0.14). However, number of patients having at least one postoperative complication is significantly lower with use of GDFT (OR 0.57; 95 % CI 0.43, 0.75; p < 0.0001). Abdominal complications (p = 0.008), wound infection (p = 0.002) and postoperative hypotension (p = 0.04) are also decreased with used of GDFT as opposed to a standard care. Though patients who received GDFT were infused more colloid (p < 0.0001), there is no increased risk of heart failure or pulmonary edema and renal failure.

CONCLUSION

GDFT in major non- cardiac surgical patients has questionable benefit over a standard care in terms of postoperative mortality, length of hospital stay and length of ICU stay. However, incidence of all complications including wound infection, abdominal complications and postoperative hypotension is reduced.

Potential return on investment for implementation of perioperative goal-directed fluid therapy in major surgery: a nationwide database study

Background

Preventable postsurgical complications are increasingly recognized as a major clinical and economic burden. A recent meta-analysis showed a 17–29 % decrease in postoperative morbidity with goal-directed fluid therapy. Our objective was to estimate the potential economic impact of perioperative goal-directed fluid therapy.

Methods

We studied 204,680 adult patients from 541 US hospitals who had a major non-cardiac surgical procedure between January 2011 and June 2013. Hospital costs (including 30-day readmission costs) in patients with and without complications were extracted from the Premier Inc. research database, and potential cost-savings associated with a 17–29 % decrease in postoperative morbidity were estimated.

Results

A total of 76,807 patients developed one or more postsurgical complications (morbidity rate 37.5 %). In patients with and without complications, hospital costs were US$27,607 ± 32,788 and US$15,783 ± 12,282 (p < 0.0001), respectively. Morbidity rate was anticipated to decrease to 26.6–31.1 % with goal-directed fluid therapy, yielding potential gross cost-savings of US$153–263 million for the study period, US$61–105 million per year, or US$754–1286 per patient. Potential savings per patient were highly variable from one surgical procedure to the other, ranging from US$354–604 for femur and hip-fracture repair to US$3515–5996 for esophagectomies. When taking into account the volume of procedures, the total potential savings per year were the most significant (US$32–55 million) for colectomies.

Conclusions

Postsurgical complications occurred in more than one third of our study population and had a dramatic impact on hospital costs. With goal-directed fluid therapy, potential cost-savings per patient were US$754–1286. The highest cost-savings per year were observed for colectomies. These projections should help hospitals estimate the return on investment when considering the implementation of goal-directed fluid therapy.

Electronic supplementary material

The online version of this article (doi:10.1186/s13741-015-0021-0) contains supplementary material, which is available to authorized users.

Defining goals of resuscitation in the critically ill patient

There is still no "universal" consensus on an optimal endpoint for goal directed therapy (GDT) in the critically ill patient. As in other areas of medicine, this should help providers to focus on a more "individualized approach" rather than a protocolized approach to ensure proper patient care. Hemodynamic optimization needs more than simply blood pressure, heart rate, central venous pressure and urine output monitoring. It is essential to also monitor flow variables (cardiac output/stroke volume) and dynamic parameters of fluid responsiveness whenever available. This article will provide a review of current and trending approaches of the goals of resuscitation in the critically ill patient.

Monitoring needs and goal-directed fluid therapy within an enhanced recovery program

Patients having major abdominal surgery need perioperative fluid supplementation; however, enhanced recovery principles mitigate against many of the factors that traditionally led to relative hypovolemia in the perioperative period. An estimate of fluid requirements for abdominal surgery can be made but individualization of fluid prescription requires consideration of clinical signs and hemodynamic variables. The literature supports goal-directed fluid therapy. Application of this evidence to justify stroke volume optimization in the setting of major surgery within an enhanced recovery program is controversial. This article places the evidence in context, reviews controversies, and suggests implications for current practice and future research.

AKI associated with cardiac surgery

Approximately 18% of patients undergoing cardiac surgery experience AKI (on the basis of modern standardized definitions of AKI), and approximately 2%-6% will require hemodialysis. The development of AKI after cardiac surgery portends poor short- and long-term prognoses, with those developing RIFLE failure or AKI Network stage III having an almost 2-fold increase in the risk of death. AKI is caused by a variety of factors, including nephrotoxins, hypoxia, mechanical trauma, inflammation, cardiopulmonary bypass, and hemodynamic instability, and it may be affected by the clinician's choice of fluids and vasoactive agents as well as the transfusion strategy used. The risk of AKI may be ameliorated by avoidance of nephrotoxins, achievement of adequate glucose control preoperatively, and use of goal-directed therapy hemodynamic strategies. Remote ischemic preconditioning is an exciting future strategy, but more work is needed before widespread implementation. Unfortunately, there are no pharmacologic agents known to reduce the risk of AKI or treat established AKI.

The effects of goal-directed fluid therapy based on dynamic parameters on post-surgical outcome: a meta-analysis of randomized controlled trials

Introduction

Dynamic predictors of fluid responsiveness, namely systolic pressure variation, pulse pressure variation, stroke volume variation and pleth variability index have been shown to be useful to identify in advance patients who will respond to a fluid load by a significant increase in stroke volume and cardiac output. As a result, they are increasingly used to guide fluid therapy. Several randomized controlled trials have tested the ability of goal-directed fluid therapy (GDFT) based on dynamic parameters (GDFTdyn) to improve post-surgical outcome. These studies have yielded conflicting results. Therefore, we performed this meta-analysis to investigate whether the use of GDFTdyn is associated with a decrease in post-surgical morbidity.

Methods

A systematic literature review, using MEDLINE, EMBASE, and The Cochrane Library databases through September 2013 was conducted. Data synthesis was obtained by using odds ratio (OR) and weighted mean difference (WMD) with 95% confidence interval (CI) by random-effects model.

Results

In total, 14 studies met the inclusion criteria (961 participants). Post-operative morbidity was reduced by GDFTdyn (OR 0.51; CI 0.34 to 0.75; P <0.001). This effect was related to a significant reduction in infectious (OR 0.45; CI 0.27 to 0.74; P = 0.002), cardiovascular (OR 0.55; CI 0.36 to 0.82; P = 0.004) and abdominal (OR 0.56; CI 0.37 to 0.86; P = 0.008) complications. It was associated with a significant decrease in ICU length of stay (WMD −0.75 days; CI −1.37 to −0.12; P = 0.02).

Conclusions

In surgical patients, we found that GDFTdyn decreased post-surgical morbidity and ICU length of stay. Because of the heterogeneity of studies analyzed, large prospective clinical trials would be useful to confirm our findings.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0584-z) contains supplementary material, which is available to authorized users.

Tackling the economic burden of postsurgical complications: would perioperative goal-directed fluid therapy help?

INTRODUCTION

Pay-for-performance programs and economic constraints call for solutions to improve the quality of health care without increasing costs. Many studies have shown decreased morbidity in major surgery when perioperative goal directed fluid therapy (GDFT) is used. We assessed the clinical and economic burden of postsurgical complications in the University HealthSystem Consortium (UHC) in order to predict potential savings with GDFT.

METHODS

Data from adults who had a major surgical procedure in 2011 were screened in the UHC database. Thirteen post-surgical complications were tabulated. In-hospital mortality, hospital length of stay and costs from patients with and without complications were compared. The risk ratios reported by the most recent meta-analysis were used to estimate the potential reduction in post-surgical morbidity with GDFT. Potential cost-savings were calculated from the actual and anticipated morbidity rates.

RESULTS

A total of 75,140 patients met the search criteria, and 8,421 patients developed one or more post-surgical complications (morbidity rate 11.2%). In patients with and without complications, in-hospital mortality was 12.4% and 1.4% (P <0.001), mean hospital length of stay was 20.5 ± 20.1 days and 8.1 ± 7.1 days (P <0.001) and mean direct costs were $47,284 ± 49,170 and $17,408 ± 15,612 (P < 0.001), respectively. With GDFT, morbidity rate was projected to decrease to 8.0 - 9.3%, yielding gross costs savings of $43 M - $73 M for the study population or $569 - $970 per patient.

CONCLUSION

Postsurgical complications have a dramatic impact (+172%) on costs. Potential costs savings resulting from GDFT are substantial. Perioperative GDFT may be recommended not only to improve quality of care but also to decrease costs.

Liberal or restricted fluid administration: are we ready for a proposal of a restricted intraoperative approach?

BACKGROUND

Fluid management in the perioperative period has been extensively studied but, despite that, "the right amount" still remains uncertain. The purpose of this paper is to summarize the state of the art of intraoperative fluid approach today.

DISCUSSION

In the current medical literature there are only heterogeneous viewpoints that gives the idea of how confusing the situation is. The approach to the intraoperative fluid management is complex and it should be based on human physiology and the current evidence.

SUMMARY

An intraoperative restrictive fluid approach in major surgery may be beneficial while Goal-directed Therapy should be superior to the liberal fluid strategy. Finally, we propose a rational approach currently used at our institution.

State-of-the-art fluid management in the operating room

The underlying principles guiding fluid management in any setting are very simple: maintain central euvolemia, and avoid salt and water excess. However, these principles are frequently easier to state than to achieve. Evidence from recent literature suggests that avoidance of fluid excess is important, with excessive crystalloid use leading to perioperative weight gain and an increase in complications. A zero-balance approach aimed at avoiding fluid excess is recommended for all patients. For major surgery, there is a sizeable body of evidence that an individualized goal-directed fluid therapy (GDFT) improves outcomes. However, within an Enhanced Recovery program only a few studies have been published, yet so far GDFT has not achieved the same benefit. Balanced crystalloids are recommended for most patients. The use of colloids remains controversial; however, current evidence suggests they can be beneficial in intraoperative patients with objective evidence of hypovolemia.

Hybrid measurement to achieve satisfactory precision in perioperative cardiac output monitoring

Advanced haemodynamic monitoring employing minimally invasive cardiac output measurement may lead to significant improvements in patient outcomes in major surgery. However, the precision (scatter) of measurement of available generic technologies has been shown to be unsatisfactory with percentage error of agreement with bolus thermodilution (% error) of 40% to 50%. Simultaneous measurement and averaging by two or more technologies may reduce random measurement scatter and improve precision. This concept, called the hybrid method, was tested by comparing accuracy and precision of measurement relative to bolus thermodilution using combinations of three component methods. Thirty patients scheduled for either elective cardiac surgery or liver transplantation were studied. Agreement with simultaneous bolus thermodilution of hybrid combinations of continuous thermodilution (QtCCO) or Vigeleo™/FloTrac™ pulse contour measurement (QtFT) with pulmonary Capnotracking (QtCO2) was assessed pre- and post-cardiopulmonary bypass or pre- and post-reperfusion of the donor liver and compared with that of the component methods alone. Hybridisation of QtCO2 (% error 42.2) and QtCCO (% error 51.3) achieved significantly better precision (% error 31.3) than the component methods (P=0.0004) and (P=0.0195). Due to poor inherent precision of QtFT (% error 82.8), hybrid combination of QtFT with QtCO2 did not result in better precision than QtCO2 alone. Hybrid measurement can approach a 30% error, which is recommended as the upper limit for acceptability. This is a practical option where at least one component method, such as Capnotracking, is automated and does not increase the cost or complexity of the measurement process.

Considerations for the use of short-acting opioids in general anesthesia

Anesthesiologists play a critical role in facilitating a positive perioperative experience and early recovery for patients. Depending on the kind of procedure or surgery, a wide variety of agents and techniques are currently available to anesthesiologists to administer safe and efficacious anesthesia. Notably, the fast-track or ambulatory surgery environment requires the use of agents that enable rapid induction, maintenance, and emergence combined with minimal adverse effects. Short-acting opioids demonstrate a safe and rapid onset/offset of effect; that short effect is both predictable and precise. It also ensures easier titration and reduced or rapidly reversed side effects. Due to their distinct pharmacokinetic and pharmacodynamic properties, and, in one case, rapid extra-hepatic clearance of remifentanil, these agents have several applications in general anesthesia.

First closed-loop goal directed fluid therapy during surgery: a pilot study

OBJECTIVE

Intraoperative haemodynamic optimization based on fluid management and stroke volume optimization (Goal Directed Fluid Therapy [GDFT]) can improve patients' postoperative outcome. We have described a closed-loop fluid management system based on stroke volume variation and stroke volume monitoring. The goal of this system is to apply GDFT protocols automatically. After conducting simulation, engineering, and animal studies the present report describes the first use of this system in the clinical setting.

STUDY DESIGN

Prospective pilot study.

PATIENTS

Patients undergoing major surgery.

METHODS

Twelve patients at two institutions had intraoperative GDFT delivered by closed-loop controller under the direction of an anaesthesiologist. Compliance with GDFT management was defined as acceptable when a patient spent more than 85% of the surgery time in a preload independent state (defined as stroke volume variation<13%), or when average cardiac index during the case was superior or equal to 2.5l/min/m(2).

RESULTS

Closed-loop GDFT was completed in 12 patients. Median surgery time was 447 [309-483] min and blood loss was 200 [100-1000] ml. Average cardiac index was 3.2±0.8l/min/m(2) and on average patients spent 91% (76 to 100%) of the surgery time in a preload independent state. Twelve of 12 patients met the criteria for compliance with intraoperative GDFT management.

CONCLUSION

Intraoperative GDFT delivered by closed-loop system under anaesthesiologist guidance allowed to obtain targeted objectives in 91% of surgery time. This approach may provide a way to ensure consistent high-quality delivery of fluid administration and compliance with perioperative goal directed therapy.

Pulmonary carbon dioxide elimination for cardiac output monitoring in peri-operative and critical care patients: history and current status

Minimally invasive measurement of cardiac output as a central component of advanced haemodynamic monitoring has been increasingly recognised as a potential means of improving perioperative outcomes in patients undergoing major surgery. Methods based upon pulmonary carbon dioxide elimination are among the oldest techniques in this field, with comparable accuracy and precision to other techniques. Modern adaptations of these techniques suitable for use in the perioperative and critical are environment are based on the differential Fick approach, and include the partial carbon dioxide rebreathing method. The accuracy and precision of this approach to cardiac output measurement has been shown to be similar to other minimally invasive techniques. This paper reviews the underlying principles and evolution of the method, and future directions including recent adaptations designed to deliver continuous breath-by-breath monitoring of cardiac output.

Current practice in hemodynamic monitoring and management in high-risk surgery patients: a national survey of Korean anesthesiologists

Background

Hemodynamic optimization improves postoperative outcomes in high-risk surgery patients. The monitoring of cardiac output (CO) and dynamic parameters of fluid responsiveness can guide hemodynamic optimization. We conducted a survey to assess the current hemodynamic monitoring and management practices of Korean anesthesiologists during high-risk surgery.

Methods

E-mails containing a link to our survey, which consisted of 33 questions relating to hemodynamic monitoring during high-risk surgery, were sent to 3,943 members of the Korean Society of Anesthesiologists (KSA). The survey web page was open from December 30, 2011 to March 31, 2012.

Results

A total of 139 anesthesiologists responded during the survey period. Invasive arterial pressure (97.2%) and central venous pressure (93.4%) were routinely monitored. CO was monitored in 58.5% of patients; stroke volume variations were monitored in 50.9% of patients. However, CO was consistently optimized by < 20% of anesthesiologists. An arterial pressure waveform-derived CO monitor was the most frequently used device to monitor CO (79.0%). Blood pressure, urine output, central venous pressure, and clinical experience were considered to be the best indicators of volume expansion than CO or dynamic parameters of fluid responsiveness.

Conclusions

The survey revealed that KSA members frequently monitor CO and dynamic parameters of fluid responsiveness during high-risk surgery. However, static indices were used more often to judge volume expansion. The current study reveals that CO is not frequently optimized despite the relatively high incidence of CO monitoring during high-risk surgery in Korea.

Clinical review: What are the best hemodynamic targets for noncardiac surgical patients?

Perioperative hemodynamic optimization, or goal-directed therapy (GDT), has been show to significantly decrease complications and risk of death in high-risk patients undergoing noncardiac surgery. An important aim of GDT is to prevent an imbalance between oxygen delivery and oxygen consumption in order to avoid the development of multiple organ dysfunction. The utilization of cardiac output monitoring in the perioperative period has been shown to improve outcomes if integrated into a GDT strategy. GDT guided by dynamic predictors of fluid responsiveness or functional hemodynamics with minimally invasive cardiac output monitoring is suitable for the majority of patients undergoing major surgery with expected significant volume shifts due to bleeding or other significant intravascular volume losses. For patients at higher risk of complications and death, such as those with advanced age and limited cardiorespiratory reserve, the addition of dobutamine or dopexamine to the treatment algorithm, to maximize oxygen delivery, is associated with better outcomes.

[Do anesthetic techniques influence postoperative outcomes? Part I]

The influence of anesthetic technique on postoperative outcomes has opened a wide field of research in recent years. High-risk patients undergoing non-cardiac surgery are those who have higher incidence of postoperative complications and mortality. A proper definition of this group of patients should focus maximal efforts and resources to improve the results. In view of the significant reduction in postoperative mortality and morbidity in last 20 years, perioperative research should take into account new indicators to investigate the role of anesthetic techniques on postoperative outcomes. Studies focused on the evaluation of intermediate outcomes would probably discriminate better effectiveness differences between anesthetic techniques. We review some of the major controversies arising in the literature about the impact of anesthetic techniques on postoperative outcomes. We have grouped the impact of these techniques into 9 major investigation areas: mortality, cardiovascular complications, respiratory complications, postoperative cognitive dysfunction, chronic postoperative pain, cancer recurrence, postoperative nausea/vomiting, surgical outcomes and resources utilization. In this first part of the review, we discuss the basis on postoperative outcomes research, mortality, cardiovascular and respiratory complications.

Effects of phenylephrine on cardiac output and venous return depend on the position of the heart on the Frank-Starling relationship

Introduction: phenylephrine is used daily during anesthesia for treating hypotension. However, the effects of phenylephrine on cardiac output (CO) are not clear. We hypothesized that the impact of phenylephrine on cardiac output is related to preload dependency. Methods: eight pigs were studied at a preload independent stage (after CO augmentation) and at a preload dependent stage (after a 21 ml/kg hemorrhage). At each stage, phenylephrine boluses (0.5, 1.0, 2.0, and 4.0 μg/kg) were given randomly while mean arterial pressure (MAP), CO, inferior vena cava flow (IVCf) (both measured using ultrasonic flow probes), and pulse pressure variation were measured. Results: at the preload independent stage, phenylephrine boluses induced significant increases in MAP (from 72 ± 6 to 100 ± 6 mmHg; P < 0.05) and decreases in CO and IVCf (from 7.0 ± 0.8 to 6.0 ± 1.1 l/min and from 4.6 ± 0.5 to 3.8 ± 0.6 l/min, respectively). At the preload-dependent stage, phenylephrine boluses induced significant increases in MAP (from 40 ± 7 to 65 ± 9 mmHg), CO (from 4.1 ± 0.6 to 4.9 ± 0.7 l/min), and IVCf (from 3.0 ± 0.4 to 3.5 ± 0.6 l/min; all data presented are for 4 μg/kg). Incremental doses of phenylephrine induced incremental changes in cardiac output. A pulse pressure variation >16.4% before phenylephrine predicted an increase in stroke volume with a 93% sensitivity and a 100% specificity. Conclusion: impact of phenylephrine on cardiac output is related to preload dependency. When the heart is preload independent, phenylephrine boluses induce on average a decrease in cardiac output. When the heart is preload dependent, phenylephrine boluses induce on average an increase in cardiac output.