Association between perioperative fluid administration and postoperative outcomes: a 20-year systematic review and a meta-analysis of randomized goal-directed trials in major visceral/noncardiac surgery

Stroke volume variation induced by lung recruitment maneuver to predict fluid responsiveness in patients receiving mechanical ventilation: A systematic review and meta-analysis

STUDY OBJECTIVE

The aim of this study was to evaluate the accuracy of lung recruitment maneuver induced stroke volume variation (ΔSVLRM) in predicting fluid responsiveness in mechanically ventilated adult patients by systematic review and meta-analysis.

METHODS

A comprehensive electronic search of relevant literature was conducted in PubMed, Web of Science, Cochrane Library, Ovid Medline, Embase and Chinese databases (including China National Knowledge Infrastructure, Wanfang and VIP databases). Review Manager 5.4, Meta-DiSc 1.4 and STATA 16.0 were selected for data analysis, and QUADAS-2 tool was used for quality assessment. Data from selected studies were pooled to obtain sensitivity, specificity, diagnostic likelihood ratio (DLR) of positive and negative, diagnostic odds ratio (DOR), and summary receiver operating characteristic curve.

RESULTS

A total of 6 studies with 256 patients were enrolled through March 2024. The risk of bias and applicability concerns for each included study were low, and there was no significant publication bias. There was moderate to substantial heterogeneity for the non-threshold effect, but not for the threshold effect. The combined sensitivity and specificity were 0.84 (95% CI, 0.77-0.90) and 0.79 (95% CI, 0.70-0.86), respectively. The DOR and the area under the curve (AUC) were 22.15 (95%CI, 7.62-64.34) and 0.90 (95% CI, 0.87-0.92), respectively. The positive and negative predictive values of DLR were 4.53 (95% CI, 2.50-8.18) and 0.19 (95% CI, 0.11-0.35), respectively. Fagan's nomogram showed that with a pre-test probability of 52%, the post-test probability reached 83% and 17% for the positive and negative tests, respectively.

CONCLUSIONS

Based on the currently available evidence, ΔSVLRM has a good diagnostic value for predicting the fluid responsiveness in adult patients undergoing mechanical ventilation. Given the heterogeneity and limitations of the published data, further studies with large sample sizes and different clinical settings are needed to confirm the diagnostic value of ΔSVLRM in predicting fluid responsiveness. PROSPERO registration number: CRD42023490598.

High intraoperative fluid load associated with prolonged length of hospital stay and complications after non-cardiac surgery in neonates

Inappropriate perioperative fluid load can lead to postoperative complications and death. This retrospective study was designed to investigate the association between intraoperative fluid load and outcomes in neonates undergoing non-cardiac surgery. From April 2020 to September 2022, 940 neonates who underwent non-cardiac surgery were retrospectively enrolled and their perioperative data were harvested for further analysis. According to recorded intraoperative fluid volumes defined as ml.kg-1 h-1, patients were mandatorily divided into quintile with fluid load as restrictive (quintile 1, Q1), moderately restrictive (Q2), moderate (Q3), moderately liberal (Q4), and liberal (Q5). The primary outcomes were defined as prolonged length of hospital stay (LOS) (postoperative LOS ≥ 14 days), complications beyond prolonged LOS, and 30-day mortality. Secondary outcomes included postoperative complications within 14 days of hospital stay. The intraoperative fluid load was in Q1 of 6.5 (5.3-7.3) (median and IQR); Q2: 9.2 (8.7-9.9); Q3: 12.2 (11.4-13.2); Q4: 16.5 (15.4-18.0); and Q5: 26.5 (22.3-32.2) ml.kg-1 h-1. The odd of prolonged LOS was positively correlated with an increase fluid volume (Q5 quintile: OR 2.602 [95% CI 1.444-4.690], P = 0.001), as well as complications beyond prolonged LOS (Q5: OR 3.322 [95% CI 1.656-6.275], P = 0.001). The overall 30-day mortality rate was increased with high intraoperative fluid load but did not reach to a statistical significance after adjusted with confounders. Furthermore, the highest quintile of fluid load (26.5 ml.kg-1 h-1, IQR [22.3-32.2]) (Q5 quintile) was significantly associated with longer postoperative mechanical ventilation time compared with Q1 (Q5: OR 2.212 [95% CI 1.101-4.445], P = 0.026).    Conclusion: Restrictive intraoperative fluid load had overall better outcomes, whilst high fluid load was significantly associated with prolonged LOS and complications after non-cardiac surgery in neonates.    Trial registration:  Chictr.org.cn Identifier: ChiCTR2200066823 (December 19, 2022). What is Known: • Inappropriate perioperative fluid load can lead to postoperative complications and even death. What is New: • High perioperative fluid load was significantly associated with an increased length of stay after non-cardiac surgery in neonates, whilst low fluid load was consistently related to better postoperative outcomes.

Comparison of Dynamic Measures in Intraoperative Goal-Directed Fluid Therapy of Patients with Morbid Obesity Undergoing Laparoscopic Sleeve Gastrectomy

INTRODUCTION

Obesity increases the risk of morbidity and mortality during surgical procedures. Goal-directed fluid therapy (GDFT) is a new concept for perioperative fluid management that has been shown to improve patient prognosis. This study aimed to investigate the role of the Pleth Variability Index (PVI), systolic pressure variation (SPV), and pulse pressure variation (PPV) in maintaining tissue perfusion and renal function during GDFT management in patients undergoing laparoscopic sleeve gastrectomy (LSG).

MATERIALS AND METHODS

Two hundred ten patients were enrolled in our prospective randomized controlled clinical trial. Demographic data, hemodynamic parameters, biochemical parameters, the amount of crystalloid and colloid fluid administered intraoperatively, and the technique of goal-directed fluid management used were recorded. Patients were randomly divided into three groups: PVI (n = 70), PPV (n = 70), and SPV (n = 70), according to the technique of goal-directed fluid management. Postoperative nausea and vomiting, time of return of bowel movement, and hospital stay duration were recorded.

RESULTS

There was no statistically significant difference between the number of crystalloids administered in all three groups. However, the amount of colloid administered was statistically significantly lower in the SPV group than in the PVI group, and there was no significant difference in the other groups. Statistically, there was no significant difference between the groups in plasma lactate, blood urea, and creatinine levels.

CONCLUSION

In LSG, dynamic measurement techniques such as PVI, SPV, and PPV can be used in patients with morbid obesity without causing intraoperative and postoperative complications. PVI may be preferred over other invasive methods because it is noninvasive.

The Use of Pressure Recording Analytical Method in Patients Undergoing Endovascular Repair for Abdominal Aortic Aneurysm: The Impact on Clinical Decisions for the Appropriate Postoperative Setting and Cost-effective Analysis

OBJECTIVE

To analyze the use of the Pressure Recording Analytical Method (PRAM), an hemodynamic monitoring system, in evaluating intraoperative and postoperative hemodynamic instability in patients undergoing endovascular repair for abdominal aortic aneurysm, and to evaluate if the decision to refer patients to a ordinary ward or to a Cardiac Step-Down Unit (CSDU) after the intervention on the basis of intraoperative hemodynamic monitoring could be more cost-effective.

MATERIALS AND METHODS

After preoperative clinical evaluation, 44 patients were divided in this non-randomised study into two groups according to their postoperative destination: Group 1-ward (N=22) and Group 2-CSDU (N=22). All patients underwent monitoring with PRAM during the intervention and in the 24 postoperative hours, measuring several indices of myocardial contractility and other hemodynamic variables.

RESULTS

According to the variability of two parameters, Stroke Volume Variation and Pulse Pressure Variation, patients were classified as stable or unstable. Unstable patients showed a significant alteration in several hemodynamic indices, in comparison to stable ones. According to the intraoperative monitoring, eight high risk patients could have been sent to an ordinary ward due to their stability, with a reduction in the improper use of CSDU and, consequently, in costs.

CONCLUSIONS

Hemodynamic monitoring with PRAM can be useful in these patients, both for intraoperative management and for the choice of the more appropriate postoperative setting, possibly reducing the improper use of CSDU for hemodynamically stable patients who are judged to be at high risk preoperatively, and re-evaluating low surgical risk patients with an unstable intraoperative pattern, with a possible reduction in costs.

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.

The Incidence of Perioperative Hypotension in Patients Undergoing Major Abdominal Surgery with the Use of Arterial Waveform Analysis and the Hypotension Prediction Index Hemodynamic Monitoring-A Retrospective Analysis

Intraoperative hypotension (IH) is common in patients receiving general anesthesia and can lead to serious complications such as kidney failure, myocardial injury and increased mortality. The Hypotension Prediction Index (HPI) algorithm is a machine learning system that analyzes the arterial pressure waveform and alerts the clinician of an impending hypotension event. The purpose of the study was to compare the frequency of perioperative hypotension in patients undergoing major abdominal surgery with different types of hemodynamic monitoring. The study included 61 patients who were monitored with the arterial pressure-based cardiac output (APCO) technology (FloTrac group) and 62 patients with the Hypotension Prediction Index algorithm (HPI group). Our primary outcome was the time-weighted average (TWA) of hypotension below < 65 mmHg. The median TWA of hypotension in the FloTrac group was 0.31 mmHg versus 0.09 mmHg in the HPI group (p = 0.000009). In the FloTrac group, the average time of hypotension was 27.9 min vs. 8.1 min in the HPI group (p = 0.000023). By applying the HPI algorithm in addition to an arterial waveform analysis alone, we were able to significantly decrease the frequency and duration of perioperative hypotension events in patients who underwent major abdominal surgery.

Modern fluid management in thoracic surgery

PURPOSE OF REVIEW

To provide an approach to perioperative fluid management for lung resection patients that incorporates the entire patient pathway in the context of international guidelines on enhanced recovery after surgery (ERAS).

RECENT FINDINGS

The concern with intraoperative fluid management is that giving too little or too much fluid is associated with worse outcomes after lung resection. However, it has not emerged as a key care element in thoracic ERAS programs probably due to the influence of other ERAS elements. Carbohydrate loading 2 h before surgery and the allowance of water until just prior to induction ensures the patient is both well hydrated and metabolically normal when they enter the operating room. Consequently, maintaining a euvolemic state during anesthesia can be achieved without goal-directed fluid therapy despite the recommendations of some guidelines. Intravenous fluids can be safely stopped in the immediate postoperative period.

SUMMARY

The goal of perioperative euvolemia can be achieved with the ongoing evolution and application of ERAS principles. A focus on the pre and postoperative phases of fluid management and a pragmatic approach to intraoperative fluid management negates the need for goal-directed fluid therapy in most cases.

Update on guidelines and recommendations for enhanced recovery after thoracic surgery

PURPOSE OF REVIEW

Enhanced recovery after thoracic surgery (ERATS) has continued its growth in popularity over the past few years, and evidence for its utility is catching up to other specialties. This review will present and examine some of that accumulated evidence since guidelines sponsored by the Enhanced Recovery after Surgery (ERAS) Society and the European Society of Thoracic Surgeons (ESTS) were first published in 2019.

RECENT FINDINGS

The ERAS/ESTS guidelines published in 2019 have not been updated, but new studies have been done and new data has been published regarding some of the individual components of the guidelines as they relate to thoracic and lung resection surgery. While there is still not a consensus on many of these issues, the volume of available evidence is becoming more robust, some of which will be incorporated into this review.

SUMMARY

The continued accumulation of data and evidence for the benefits of enhanced recovery techniques in thoracic and lung resection surgery will provide the thoracic anesthesiologist with guidance on how to best care for these patients before, during, and after surgery. The data from these studies will also help to elucidate which components of ERAS protocols are the most beneficial, and which components perhaps do not provide as much benefit as previously thought.

Perioperative Fluid and Vasopressor Therapy in 2050: From Experimental Medicine to Personalization Through Automation

Intravenous (IV) fluids and vasopressor agents are key components of hemodynamic management. Since their introduction, their use in the perioperative setting has continued to evolve, and we are now on the brink of automated administration. IV fluid therapy was first described in Scotland during the 1832 cholera epidemic, when pioneers in medicine saved critically ill patients dying from hypovolemic shock. However, widespread use of IV fluids only began in the 20th century. Epinephrine was discovered and purified in the United States at the end of the 19th century, but its short half-life limited its implementation into patient care. Advances in venous access, including the introduction of the central venous catheter, and the ability to administer continuous infusions of fluids and vasopressors rather than just boluses, facilitated the use of fluids and adrenergic agents. With the advent of advanced hemodynamic monitoring, most notably the pulmonary artery catheter, the role of fluids and vasopressors in the maintenance of tissue oxygenation through adequate cardiac output and perfusion pressure became more clearly established, and hemodynamic goals could be established to better titrate fluid and vasopressor therapy. Less invasive hemodynamic monitoring techniques, using echography, pulse contour analysis, and heart-lung interactions, have facilitated hemodynamic monitoring at the bedside. Most recently, advances have been made in closed-loop fluid and vasopressor therapy, which apply computer assistance to interpret hemodynamic variables and therapy. Development and increased use of artificial intelligence will likely represent a major step toward fully automated hemodynamic management in the perioperative environment in the near future. In this narrative review, we discuss the key events in experimental medicine that have led to the current status of fluid and vasopressor therapies and describe the potential benefits that future automation has to offer.

Perioperative Fluid Management in Colorectal Surgery: Institutional Approach to Standardized Practice

The present review discusses restrictive perioperative fluid protocols within enhanced recovery after surgery (ERAS) pathways. Standardized definitions of a restrictive or liberal fluid regimen are lacking since they depend on conflicting evidence, institutional protocols, and personal preferences. Challenges related to restrictive fluid protocols are related to proper patient selection within standardized ERAS protocols. On the other hand, invasive goal-directed fluid therapy (GDFT) is reserved for more challenging disease presentations and polymorbid and frail patients. While the perfusion rate (mL/kg/h) appears less predictive for postoperative outcomes, the authors identified critical thresholds related to total intravenous fluids and weight gain. These thresholds are discussed within the available evidence. The authors aim to introduce their institutional approach to standardized practice.

High versus standard blood pressure target in hypertensive high-risk patients undergoing elective major abdominal surgery: a study protocol for the HISTAP randomized clinical trial

BACKGROUND

The intraoperative period is often characterized by hemodynamic instability, and intraoperative hypotension is a common complication. The optimal mean arterial pressure (MAP) target in hypertensive patients is still not clear. We hereby describe the protocol and detailed statistical analysis plan for the high versus standard blood pressure target in hypertensive high-risk patients undergoing elective major abdominal surgery: the HISTAP randomized clinical trial. The HISTAP trial aims at addressing whether the use of a higher intraoperative MAP target in high-risk hypertensive surgical patients scheduled for elective abdominal surgery would improve postoperative outcomes, as compared to the standard and recommended perioperative MAP, by using a composite outcome including a 30-day mortality from surgical intervention and at least one major organ dysfunction or new onset of sepsis and septic shock occurring 7 days after surgery.

METHODS

The HISTAP trial is an investigator-initiated, pragmatic, parallel-grouped, randomized, stratified, analyst-blinded trial with adequate allocation sequence generation, and allocation concealment. We will allocate 636 patients to a MAP target ≥ 80 mmHg (treatment group) or to a MAP target ≥65 mmHg (control group). The primary outcome is a composite outcome including a 30-day mortality from the operation and major organ complications. Secondary outcomes are mortality at 30 days, intensive care unit (ICU) length of stay, ICU readmission, Sequential Organ Failure Assessment (SOFA) scores recorded up to postoperative day 7, overall intraoperative fluid balance, vasopressors use, and the need for reoperation. An unadjusted χ2 test will be used for the primary outcome analysis. A Cox proportional hazards model will be used to adjust the association between the primary outcome and baseline covariates.

CONCLUSIONS

The HISTAP trial results will provide important evidence to guide clinicians' choice regarding the intraoperative MAP target in high-risk hypertensive patients scheduled for elective abdominal surgery.

Respiratory variation in the internal jugular vein does not predict fluid responsiveness in the prone position during adolescent idiopathic scoliosis surgery: a prospective cohort study

BACKGROUND

Respiratory variation in the internal jugular vein (IJVV) has not shown promising results in predicting volume responsiveness in ventilated patients with low tidal volume (Vt) in prone position. We aimed to determine whether the baseline respiratory variation in the IJVV value measured by ultrasound might predict fluid responsiveness in patients with adolescent idiopathic scoliosis (AIS) undergoing posterior spinal fusion (PSF) with low Vt.

METHODS

According to the fluid responsiveness results, the included patients were divided into two groups: those who responded to volume expansion, denoted the responder group, and those who did not respond, denoted the non-responder group. The primary outcome was determination of the value of baseline IJVV in predicting fluid responsiveness (≥15% increases in stroke volume index (SVI) after 7 ml·kg-1 colloid administration) in patients with AIS undergoing PSF during low Vt ventilation. Secondary outcomes were estimation of the diagnostic performance of pulse pressure variation (PPV), stroke volume variation (SVV), and the combination of IJVV and PPV in predicting fluid responsiveness in this surgical setting. The ability of each parameter to predict fluid responsiveness was assessed using a receiver operating characteristic curve.

RESULTS

Fifty-six patients were included, 36 (64.29%) of whom were deemed fluid responsive. No significant difference in baseline IJVV was found between responders and non-responders (25.89% vs. 23.66%, p = 0.73), and no correlation was detected between baseline IJVV and the increase in SVI after volume expansion (r = 0.14, p = 0.40). A baseline IJVV greater than 32.00%, SVV greater than 14.30%, PPV greater than 11.00%, and a combination of IJVV and PPV greater than 64.00% had utility in identifying fluid responsiveness, with a sensitivity of 33.33%, 77.78%, 55.56%, and 55.56%, respectively, and a specificity of 80.00%, 50.00%, 65.00%, and 65.00%, respectively. The area under the receiver operating characteristic curve for the baseline values of IJVV, SVV, PPV, and the combination of IJVV and PPV was 0.52 (95% CI, 0.38-0.65, p=0.83), 0.54 (95% CI, 0.40-0.67, p=0.67), 0.58 (95% CI, 0.45-0.71, p=0.31), and 0.57 (95% CI, 0.43-0.71, p=0.37), respectively.

CONCLUSIONS

Ultrasonic-derived IJVV lacked accuracy in predicting fluid responsiveness in patients with AIS undergoing PSF during low Vt ventilation. In addition, the baseline values of PPV, SVV, and the combination of IJVV and PPV did not predict fluid responsiveness in this surgical setting.

TRAIL REGISTRATION

This trial was registered at www.chictr.org (ChiCTR2200064947) on 24/10/2022. All data were collected through chart review.

Predicting fluid responsiveness using esophagus Doppler monitoring and pulse oximetry derived pleth variability index; retrospective analysis of a hemodynamic study

BACKGROUND

Fluid therapy during major surgery can be managed by providing repeated bolus infusions until stroke volume no longer increases by ≥ 10%. However, the final bolus in an optimization round increases stroke volume by < 10% and is not necessary. We studied how different cut-off values for the hemodynamic indications given by esophagus Doppler monitoring, as well as augmentation by pulse oximetry, are associated with a higher or smaller chance that stroke volume increases by ≥ 10% (fluid responsiveness) before fluid is infused.

METHODS

An esophagus Doppler and a pulse oximeter that displayed the pleth variability index were used to monitor the effects of a bolus infusion in 108 patients undergoing goal-directed fluid therapy during major open abdominal surgery.

RESULTS

The analyzed data set comprised 266 bolus infusions. The overall incidence of fluid responsiveness was 44%, but this varied greatly depending on pre-infusion hemodynamics. The likelihood of being fluid-responsive was 30%-38% in the presence of stroke volume > 80 mL, corrected flow time > 360 ms, or pleth variability index < 10%. The likelihood was 21% if stroke volume had decreased by <8% since the previous optimization, which decreased to 0% if combined with stroke volume > 100 mL. By contrast, the likelihood of fluid responsiveness increased to 50%-55% when stroke volume ≤ 50 mL, corrected flow time ≤ 360 ms, or pleth variability index ≥ 10. A decrease in stroke volume by > 8% since the previous optimization was followed by a 58% likelihood of fluid responsiveness that, in combination with any of the other hemodynamic variables, increased to 66%-76%.

CONCLUSIONS

Single or combined hemodynamic variables provided by esophagus Doppler monitoring and pulse oximetry derived pleth variability index could help clinicians avoid unnecessary fluid bolus infusions.

Association between intraoperative starch use and postoperative kidney dysfunction in patients undergoing major gastro-intestinal surgery: A propensity score-matched analysis

BACKGROUND

The impact of intraoperative starch-based fluid therapy on postoperative kidney dysfunction in patients undergoing major abdominal surgery is uncertain. Low molecular weight starch is expected to cause less postoperative kidney dysfunction.

METHODS

This retrospective study evaluated the impact of intraoperative 6% hydroxyethyl starch on postoperative renal dysfunction. The primary outcome of this study was postoperative acute kidney injury as per KDIGO definition within 72 hours of surgery.

RESULTS

This study analysed data from 461 patients with a median (interquartile range) age of 45 (33-58) years, and 48.2% of all patients were female. The proportion (95% confidence interval) of patients who developed acute kidney injury was 0.18 (0.14-0.21); 62.9% of patients had acute kidney injury stage I, 32% had acute kidney injury stage II, and the rest were acute kidney injury stage III. In the propensity score-matched sample, the average treatment effect of intraoperative colloid use on postoperative serum creatinine at day 3 (p = 0.32), duration of postoperative intensive care unit stay (p = 0.97), duration of hospital stay (p = 0.37), postoperative worst international normalised ratio (p = 0.92), and postoperative transfusion requirement (p = 0.40) were not statistically significant.

CONCLUSION

Intraoperative use of low molecular weight hydroxyethyl starch use was not associated with postoperative kidney dysfunction and coagulopathy in adult patients undergoing major open abdominal surgery.

Prognostic Factors for Postoperative Bleeding Complications and Prolonged Intensive Care after Percutaneous Hepatic Chemosaturation Procedures with Melphalan

Percutaneous hepatic melphalan perfusion (chemosaturation) in patients with liver metastases is known to be associated with procedure-related hemodynamic depression and coagulation impairment, which may cause bleeding complications and/or a prolonged intensive care unit length of stay (ICU LOS). We retrospectively analyzed possible predictive factors for bleeding complications and an ICU LOS > 1 d in a cohort of 31 patients undergoing 90 chemosaturation procedures. Using a multivariable mixed-model approach, we identified the amount of perioperative fluid volume (OR 12.0, 95% CI 2.3-60.0, p = 0.003) and protamine (OR 0.065, 95% CI 0.007-0.55, p = 0.012) to be associated with bleeding complications. Furthermore, the amount of perioperative fluid volume was associated with an ICU LOS > 1 d (OR 5.2, 95% CI 1.4-19.0, p = 0.011). Heparin dosage, melphalan dosage, extracorporeal circulation time, and noradrenaline dosage had no significant effects on outcomes. Protamine use was not associated with anaphylactic or thromboembolic complications. Despite the limited sample size, these results suggest a restrictive perioperative fluid regime to be beneficial, and support the use of protamine for heparin reversal after chemosaturation procedures. Further prospective randomized trials are needed to confirm these findings.

Implementing Enhanced Perioperative Care in Emergency General Surgery: A Prospective Multicenter Observational Study

INTRODUCTION

ERAS pathway has been proposed as the standard of care in elective abdominal surgery. Guidelines on ERAS in emergency surgery have been recently published; however, few evidences are still available in the literature. The aim of this study was to evaluate the feasibility of an enhanced recovery protocol in a large cohort of patients undergoing emergency surgery and to identify possible factors impacting postoperative protocol compliance.

METHODS

This is a prospective multicenter observational study including patients who underwent major emergency general surgery for either intra-abdominal infection or intestinal obstruction. The primary endpoint of the study is the adherence to ERAS postoperative protocol. Secondary endpoints are 30-day mortality and morbidity rates, and length of hospital stay.

RESULTS

A total of 589 patients were enrolled in the study, 256 (43.5%) of them underwent intestinal resection with anastomosis. Major complications occurred in 92 (15.6%) patients and 30-day mortality was 6.3%. Median adherence occurred on postoperative day (POD) 1 for naso-gastric tube removal, on POD 2 for mobilization and urinary catheter removal, and on POD 3 for oral intake and i.v. fluid suspension. Laparoscopy was significantly associated with adherence to postoperative protocol, whereas operative fluid infusion > 12 mL/Kg/h, preoperative hyperglycemia, presence of a drain, duration of surgery and major complications showed a negative association.

CONCLUSIONS

The present study supports that an enhanced recovery protocol in emergency surgery is feasible and safe. Laparoscopy was associated with an earlier recovery, whereas preoperative hyperglycemia, fluid overload, and abdominal drain were associated with a delayed recovery.

Intraoperative Hypotension Prediction—A Proactive Perioperative Hemodynamic Management—A Literature Review

Intraoperative hypotension (IH) is a frequent phenomenon affecting a substantial number of patients undergoing general anesthesia. The occurrence of IH is related to significant perioperative complications, including kidney failure, myocardial injury, and even increased mortality. Despite advanced hemodynamic monitoring and protocols utilizing goal directed therapy, our management is still reactive; we intervene when the episode of hypotension has already occurred. This literature review evaluated the Hypotension Prediction Index (HPI), which is designed to predict and reduce the incidence of IH. The HPI algorithm is based on a machine learning algorithm that analyzes the arterial pressure waveform as an input and the occurrence of hypotension with MAP <65 mmHg for at least 1 min as an output. There are several studies, both retrospective and prospective, showing a significant reduction in IH episodes with the use of the HPI algorithm. However, the level of evidence on the use of HPI remains very low, and further studies are needed to show the benefits of this algorithm on perioperative outcomes.

Carotid Doppler ultrasound for non-invasive haemodynamic monitoring: a narrative review

Objective.Accurate haemodynamic monitoring is the cornerstone in the management of critically ill patients. It guides the optimization of tissue and organ perfusion in order to prevent multiple organ failure. In the past decades, carotid Doppler ultrasound (CDU) has been explored as a non-invasive alternative for long-established invasive haemodynamic monitoring techniques. Considering the large heterogeneity in reported studies, we conducted a review of the literature to clarify the current status of CDU as a haemodynamic monitoring tool.Approach.In this article, firstly an overview is given of the equipment and workflow required to perform a CDU exam in clinical practice, the limitations and technical challenges potentially faced by the CDU sonographer, and the cerebrovascular mechanisms that may influence CDU measurement outcomes. The following chapter describes alternative techniques for non-invasive haemodynamic monitoring, detailing advantages and limitations compared to CDU. Next, a comprehensive review of the literature regarding the use of CDU for haemodynamic monitoring is presented. Furthermore, feasibility aspects, training requirements and technical developments of CDU are addressed.Main results.Based on the outcomes of these studies, we assess the applicability of CDU-derived parameters within three clinical domains (cardiac output, volume status, and fluid responsiveness), and amongst different patient groups. Finally, recommendations are provided to improve the quality and standardization of future research and clinical practice in this field.Significance.Although CDU is not yet interchangeable with invasive 'gold standard' cardiac output monitoring, the present work shows that certain CDU-derived parameters prove promising in the context of functional haemodynamic monitoring.

Perioperative Fluid Management and Volume Assessment

Fluid therapy is an integral component of perioperative care and helps maintain or restore effective circulating blood volume. The principal goal of fluid management is to optimize cardiac preload, maximize stroke volume, and maintain adequate organ perfusion. Accurate assessment of volume status and volume responsiveness is necessary for appropriate and judicious utilization of fluid therapy. To accomplish this, static and dynamic indicators of fluid responsiveness have been widely studied. This review discusses the overarching goals of perioperative fluid management, reviews the physiology and parameters used to assess fluid responsiveness, and provides evidence-based recommendations on intraoperative fluid management.

Pressure response to fluid challenge administration in hypotensive surgical patients: a post-hoc pharmacodynamic analysis of five datasets

In this study we evaluated the effect of fluid challenge (FC) administration in elective surgical patients with low or normal blood pressure. Secondarily, we appraised the pharmacodynamic effect of FC in normotensive and hypotensive patients. We assessed five merged datasets of patients with a baseline mean arterial pressure (MAP) above or below 65 mmHg and assessed the changes of systolic, diastolic, mean and dicrotic arterial pressures, dynamic indexes of fluid responsiveness and arterial elastance over a 10-min infusion. The hemodynamic effect was assessed by considering the net area under the curve (AUC), the maximal percentage difference from baseline (d_max), the time when the maximal value was observed (t_max) and change from baseline at 5-min (d₅) after FC end. A stroke volume index increase > 10% with respect to the baseline value after FC administration indicated fluid response. Two hundred-seventeen patients were analysed [102 (47.0%) fluid responders]. On average, FC restored a MAP [Formula: see text] 65 mmHg after 5 min. The AUCs and the d_max of pressure variables and arterial elastance of hypotensive patients were all significantly greater than normotensive patients. Pressure variables and arterial elastance changes in the hypotensive group were all significantly higher at d₅ as compared to the normotensive group. In hypotensive patients, FC restores a MAP [Formula: see text] 65 mmHg after 5 min from infusion start. The hemodynamic profile of FC in hypotensive and normotensive patients is different; both the magnitude of pressure augmentation and duration is greater in the hypotensive group.

Prediction of Fluid Responsiveness by the Effect of the Lung Recruitment Maneuver on the Perfusion Index in Mechanically Ventilated Patients During Surgery

Introduction

Excessive or inadequate fluid administration during perioperative period affects outcomes. Adjustment of volume expansion (VE) by performing fluid responsiveness (FR) test plays an important role in optimizing fluid infusion. Since changes in stroke volume (SV) during lung recruitment maneuver (LRM) can predict FR, and peripheral perfusion index (PI) is related to SV; therefore, we hypothesized that the changes in PI during LRM (ΔPILRM) could predict FR during perioperative period.

Methods

Patients who were scheduled for elective non-laparoscopic surgery under general anesthesia with a mechanical ventilator and who required VE (250 mL of crystalloid solution infusion over 10 min) were included. Before VE, LRM was performed by a continuous positive airway pressure of 30 cm H2O for 30 sec; hemodynamic variables with their changes (PI, obtained by pulse oximetry; and ΔPILRM, calculated by using [(PI before LRM—PI after LRM)/PI before LRM]*100) were obtained before and after LRM. After SV (measured by esophageal doppler) and PI had returned to the baseline values, VE was infused, and the values of these variables were recorded again, before and after VE. Fluid responders (Fluid-Res) were defined by an increase in SV ≥10% after VE. Receiver operating characteristic curves of the baseline values and ΔPILRM were constructed and reported as areas under the curve (AUC) with 95% confidence intervals, to predict FR.

Results

Of 32 mechanically ventilated adult patients included, 13 (41%) were in the Fluid-Res group. Before VE and LRM, there were no differences in the mean arterial pressure (MAP), heart rate, SV, and PI between patients in the Fluid-Res and fluid non-responders (Fluid-NonRes) groups. After LRM, SV, MAP, and, PI decreased in both groups, ΔPILRM was greater in the Fluid-Res group than in Fluid-NonRes group (55.2 ± 17.8% vs. 35.3 ± 17.3%, p &lt; 0.001, respectively). After VE, only SV and cardiac index increased in the Fluid-Res group. ΔPILRM had the highest AUC [0.81 (0.66–0.97)] to predict FR with a cut-off value of 40% (sensitivity 92.3%, specificity 73.7%).

Conclusions

ΔPILRM can be applied to predict FR in mechanical ventilated patients during the perioperative period.

Prediction of fluid responsiveness. What’s new?

Although the administration of fluid is the first treatment considered in almost all cases of circulatory failure, this therapeutic option poses two essential problems: the increase in cardiac output induced by a bolus of fluid is inconstant, and the deleterious effects of fluid overload are now clearly demonstrated. This is why many tests and indices have been developed to detect preload dependence and predict fluid responsiveness. In this review, we take stock of the data published in the field over the past three years. Regarding the passive leg raising test, we detail the different stroke volume surrogates that have recently been described to measure its effects using minimally invasive and easily accessible methods. We review the limits of the test, especially in patients with intra-abdominal hypertension. Regarding the end-expiratory occlusion test, we also present recent investigations that have sought to measure its effects without an invasive measurement of cardiac output. Although the limits of interpretation of the respiratory variation of pulse pressure and of the diameter of the vena cava during mechanical ventilation are now well known, several recent studies have shown how changes in pulse pressure variation itself during other tests reflect simultaneous changes in cardiac output, allowing these tests to be carried out without its direct measurement. This is particularly the case during the tidal volume challenge, a relatively recent test whose reliability is increasingly well established. The mini-fluid challenge has the advantage of being easy to perform, but it requires direct measurement of cardiac output, like the classic fluid challenge. Initially described with echocardiography, recent studies have investigated other means of judging its effects. We highlight the problem of their precision, which is necessary to evidence small changes in cardiac output. Finally, we point out other tests that have appeared more recently, such as the Trendelenburg manoeuvre, a potentially interesting alternative for patients in the prone position.

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.

Recovery of organ-specific tissue oxygen delivery at restrictive transfusion thresholds after fluid treatment in ovine haemorrhagic shock

Background

Fluid resuscitation is the standard treatment to restore circulating blood volume and pressure after massive haemorrhage and shock. Packed red blood cells (PRBC) are transfused to restore haemoglobin levels. Restoration of microcirculatory flow and tissue oxygen delivery is critical for organ and patient survival, but these parameters are infrequently measured. Patient Blood Management is a multidisciplinary approach to manage and conserve a patient’s own blood, directing treatment options based on broad clinical assessment beyond haemoglobin alone, for which tissue perfusion and oxygenation could be useful. Our aim was to assess utility of non-invasive tissue-specific measures to compare PRBC transfusion with novel crystalloid treatments for haemorrhagic shock.

Methods

A model of severe haemorrhagic shock was developed in an intensive care setting, with controlled haemorrhage in sheep according to pressure (mean arterial pressure 30–40 mmHg) and oxygen debt (lactate > 4 mM) targets. We compared PRBC transfusion to fluid resuscitation with either PlasmaLyte or a novel crystalloid. Efficacy was assessed according to recovery of haemodynamic parameters and non-invasive measures of sublingual microcirculatory flow, regional tissue oxygen saturation, repayment of oxygen debt (arterial lactate), and a panel of inflammatory and organ function markers. Invasive measurements of tissue perfusion, oxygen tension and lactate levels were performed in brain, kidney, liver, and skeletal muscle. Outcomes were assessed during 4 h treatment and post-mortem, and analysed by one- and two-way ANOVA.

Results

Each treatment restored haemodynamic and tissue oxygen delivery parameters equivalently (p > 0.05), despite haemodilution after crystalloid infusion to haemoglobin concentrations below 70 g/L (p < 0.001). Recovery of vital organ-specific perfusion and oxygen tension commenced shortly before non-invasive measures improved. Lactate declined in all tissues and correlated with arterial lactate levels (p < 0.0001). The novel crystalloid supported rapid peripheral vasodilation (p = 0.014) and tended to achieve tissue oxygen delivery targets earlier. PRBC supported earlier renal oxygen delivery (p = 0.012) but delayed peripheral perfusion (p = 0.034).

Conclusions

Crystalloids supported vital organ oxygen delivery after massive haemorrhage, despite haemodilution to < 70 g/L, confirming that restrictive transfusion thresholds are appropriate to support oxygen delivery. Non-invasive tissue perfusion and oximetry technologies merit further clinical appraisal to guide treatment for massive haemorrhage in the context of Patient Blood Management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40635-022-00439-6.

A COMPARATIVE STUDY OF MIPPO AND MDLIN APPLIED TO THE TREATMENT OF DISTAL TIBIAL FRACTURES

Objective: This study aims to analyze the clinical treatment effects of the minimally invasive percutaneous plate osteosynthesis (MIPPO) and multi-directional locking intramedullary nail (MDLIN) techniques in patients with distal tibial fractures. Methods: A total of 124 patients with distal tibial fractures, admitted to the People’s Hospital of Zhongjiang County from February 2019 to January 2020, were selected as the research subjects. They were randomly divided into groups ([Formula: see text]). The control group received MIPPO treatment, the observation group received MDLIN treatment, and the postoperative therapeutic effects and complications in the two groups were compared. Results: The patients in the observation group had shorter operative time and lower intraoperative blood loss than those in the control group ([Formula: see text]). The two groups had no significant differences in fracture healing time, complete weight bearing time, or functional recovery. The postoperative complication rate in the cases of the observation group was significantly lower than that of the control group ([Formula: see text]). Conclusion: Both techniques can achieve sufficient therapeutic effects; however, the MDLIN technique has certain advantages, including significantly fewer complications, lower intraoperative blood loss, and shorter operative durations compared to the MIPPO technique.

Goal-directed haemodynamic therapy during general anaesthesia for noncardiac surgery: a systematic review and meta-analysis

BACKGROUND

During general anaesthesia for noncardiac surgery, there remain knowledge gaps regarding the effect of goal-directed haemodynamic therapy on patient-centred outcomes.

METHODS

Included clinical trials investigated goal-directed haemodynamic therapy during general anaesthesia in adults undergoing noncardiac surgery and reported at least one patient-centred postoperative outcome. PubMed and Embase were searched for relevant articles on March 8, 2021. Two investigators performed abstract screening, full-text review, data extraction, and bias assessment. The primary outcomes were mortality and hospital length of stay, whereas 15 postoperative complications were included based on availability. From a main pool of comparable trials, meta-analyses were performed on trials with homogenous outcome definitions. Certainty of evidence was evaluated using Grading of Recommendations, Assessment, Development, and Evaluations (GRADE).

RESULTS

The main pool consisted of 76 trials with intermediate risk of bias for most outcomes. Overall, goal-directed haemodynamic therapy might reduce mortality (odds ratio=0.84; 95% confidence interval [CI], 0.64 to 1.09) and shorten length of stay (mean difference=-0.72 days; 95% CI, -1.10 to -0.35) but with low certainty in the evidence. For both outcomes, larger effects favouring goal-directed haemodynamic therapy were seen in abdominal surgery, very high-risk surgery, and using targets based on preload variation by the respiratory cycle. However, formal tests for subgroup differences were not statistically significant. Goal-directed haemodynamic therapy decreased risk of several postoperative outcomes, but only infectious outcomes and anastomotic leakage reached moderate certainty of evidence.

CONCLUSIONS

Goal-directed haemodynamic therapy during general anaesthesia might decrease mortality, hospital length of stay, and several postoperative complications. Only infectious postoperative complications and anastomotic leakage reached moderate certainty in the evidence.

Should fluid management in thoracic surgery be goal directed?

PURPOSE OF REVIEW

To find a reliable answer to the question in the title: Should fluid management in thoracic surgery be goal directed?

RECENT FINDINGS

'Moderate' fluid regimen is the current recommendation of fluid management in thoracic anesthesia, however, especially in more risky patients; 'Goal-Directed Therapy' (GDT) can be a more reliable approach than just 'moderate'. There are numerous studies examining its effects in general anesthesia; albeit mostly retrospective and very heterogenic. There are few studies of GDT in thoracic anesthesia with similar drawbacks.

SUMMARY

Although the evidence level is low, GDT is generally associated with fewer postoperative complications. It can be helpful in decision-making for volume-optimization, timing of fluid administration, and indication of vasoactive agents.

Observational study on fluid therapy management in surgical adult patients

Background

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

Methods

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

Results

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

Conclusions

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

Trial registration

Clinical Trials: NCT03630744.

Supplementary Information

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

Impact of Early Fluid Balance on Long-Term Mortality in Critically Ill Surgical Patients: A Retrospective Cohort Study in Central Taiwan

Fluid balance is an essential issue in critical care; however, the impact of early fluid balance on the long-term mortality in critically ill surgical patients remains unknown. This study aimed to address the impact of day 1–3 and day 4–7 fluid balance on the long-term mortality in critically ill surgical patients. We enrolled patients who were admitted to surgical intensive care units (ICUs) during 2015–2019 at a tertiary hospital in central Taiwan and retrieved date-of-death from the Taiwanese nationwide death registration profile. We used a Log-rank test and a multivariable Cox proportional hazards regression model to determine the independent mortality impact of early fluid balance. A total of 6978 patients were included for analyses (mean age: 60.9 ± 15.9 years; 63.9% of them were men). In-hospital mortality, 90-day mortality, 1-year and overall mortality was 10.3%, 15.8%, 23.8% and 31.7%, respectively. In a multivariable Cox proportional hazard regression model adjusted for relevant covariates, we found that positive cumulative day 4–7 fluid balance was independently associated with long-term mortality (aHR 1.083, 95% CI 1.062–1.105), and a similar trend was found on day 1–3 fluid balance, although to a lesser extent (aHR 1.027, 95% CI 1.011–1.043). In conclusion, the fluid balance in the first week of ICU stay, particularly day 4–7 fluid balance, may affect the long-term outcome in critically ill surgical patients.

The effects of acute kidney injury in a multicenter cohort of high-risk surgical patients

BACKGROUND AND OBJECTIVES

Patients who develop post-operative acute kidney injury (AKI) have a poor prognosis, especially when undergoing high-risk surgery. Therefore, the objective of this study was to evaluate the outcome of patients with AKI acquired after non-cardiac surgery and the possible risk factors for this complication.

METHODS

A multicenter, prospective cohort study with patients admitted to intensive care units (ICUs) after non-cardiac surgery was conducted to assess whether they developed AKI. The patients who developed AKI were then compared to non-AKI patients.

RESULTS

A total of 29 ICUs participated, of which 904 high-risk surgical patients were involved in the study. The occurrence of AKI in the post-operative period was 15.8%, and the mortality rate of post-operative AKI patients at 28 days was 27.6%. AKI was strongly associated with 28-day mortality (OR = 2.91; 95% CI 1.51-5.62; p = 0.001), and a higher length of ICU and hospital stay (p < 0.001). Independent factors for the risk of developing AKI were pre-operative anemia (OR = 7.01; 95% CI 1.69-29.07), elective surgery (OR = 0.45; 95% CI 0.21-0.97), SAPS 3 (OR = 1.04; 95% CI 1.02-1.06), post-operative vasopressor use (OR = 2.47; 95% CI 1.34-4.55), post-operative infection (OR = 8.82; 95% CI 2.43-32.05) and the need for reoperation (OR= 7.15; 95% CI 2.58-19.79).

CONCLUSION

AKI was associated with the risk of death in surgical patients and those with anemia before surgery, who had a higher SAPS 3, needed a post-operative vasopressor, or had a post-operative infection or needed reoperation were more likely to develop AKI post-operatively.

[Prevention of Surgical Site Infections]

The burden of surgical site infections (SSIs) is increasing. The number of surgical procedures continues to rise, and surgical patients present increasingly complex comorbidities. Half of SSIs are deemed preventable using evidence-based strategies. It is recommended for patients to bathe or shower prior to surgery. Hair should be removed only with a clipper. Shaving is strongly discouraged at all times. Antimicrobial prophylaxis should be administered only when indicated, based on guidelines, and timed correctly in order to achieve a bactericidal concentration in the tissues when the incision is made. Prophylaxis must not be continued beyond surgery. For skin preparation in the operating room an alcohol-based agent plus chlorhexidine or octenidine is recommended. During surgery, glycemic control and goal-directed fluid therapy should be implemented. Normothermia should be targeted in all patients. The perioperative use of an increased fraction of inspired oxygen may reduce the risk of SSI. Using a surgical safety checklist during a team time-out immediately before surgery reduces the incidence of SSI.

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 hemodynamic optimization: from guidelines to implementation-an experts' opinion paper

Despite a large body of evidence, the implementation of guidelines on hemodynamic optimization and goal-directed therapy remains limited in daily routine practice. To facilitate/accelerate this implementation, a panel of experts in the field proposes an approach based on six relevant questions/answers that are frequently mentioned by clinicians, using a critical appraisal of the literature and a modified Delphi process. The mean arterial pressure is a major determinant of organ perfusion, so that the authors unanimously recommend not to tolerate absolute values below 65 mmHg during surgery to reduce the risk of postoperative organ dysfunction. Despite well-identified limitations, the authors unanimously propose the use of dynamic indices to rationalize fluid therapy in a large number of patients undergoing non-cardiac surgery, pending the implementation of a “validity criteria checklist” before applying volume expansion. The authors recommend with a good agreement mini- or non-invasive stroke volume/cardiac output monitoring in moderate to high-risk surgical patients to optimize fluid therapy on an individual basis and avoid volume overload. The authors propose to use fluids and vasoconstrictors in combination to achieve optimal blood flow and maintain perfusion pressure above the thresholds considered at risk. Although purchase of disposable sensors and stand-alone monitors will result in additional costs, the authors unanimously acknowledge that there are data strongly suggesting this may be counterbalanced by a sustained reduction in postoperative morbidity and hospital lengths of stay. Beside existing guidelines, knowledge and explicit clinical reasoning tools followed by decision algorithms are mandatory to implement individualized hemodynamic optimization strategies and reduce postoperative morbidity and duration of hospital stay in high-risk surgical patients.