Does stroke volume variation predict intraoperative blood loss in living right donor hepatectomy?

Effect of Hydroxyethyl Starch on Acute Kidney Injury After Living Donor Hepatectomy

BACKGROUND

Concerns about the adverse effects of hydroxyethyl starch (HES) on renal function have been raised in recent studies involving critically ill patients. We aimed to evaluate the effect of HES on acute kidney injury (AKI) after living donor right hepatectomy.

METHODS

We performed a 1:3 propensity score matching analysis of the medical records of 1641 living donors who underwent a donor right hepatectomy. They were divided into the control group (n = 60), who received only crystalloids, and the colloid group (n = 1,581), who received HES 130/0.4 and crystalloids. Postoperative AKI was determined by AKI Network (AKIN) and Risk, Injury, Failure, Loss, End-stage (RIFLE) criteria.

RESULTS

A 1:3 propensity score matching was performed in 206 donors, 54 donors in the control group and 152 donors in the colloid group. For the matched colloid group, the median amount of 7.65 mL/kg (interquartile range, 6.64-9.20) of colloid and 58.19 mL/kg (interquartile range, 45.63-71.51) of crystalloid were given. The median amount of administered crystalloid in the control group was 56.48 mL/kg (interquartile range, 47.94-76.12) after propensity score matching. The incidences of AKI were not different between the control and colloid groups (P = .460 by AKIN criteria; P = .999 by RIFLE criteria).

CONCLUSION

Intraoperative administration of HES may not be associated with AKI after living donor hepatectomy. This result can provide useful information on perioperative fluid management in living liver donors.

The significance of underlying cardiac comorbidity on major adverse cardiac events after major liver resection

BACKGROUND

The risk of postoperative adverse events in patients with underlying cardiac disease undergoing major hepatectomy remains poorly characterized.

METHODS

The NSQIP database was used to identify patients undergoing hemihepatectomy and trisectionectomy. Patient characteristics and postoperative outcomes were evaluated.

RESULTS

From 2005 to 2012, 5227 patients underwent major hepatectomy. Of those, 289 (5.5%) had prior major cardiac disease: 5.6% angina, 3.1% congestive heart failure, 1% myocardial infarction, 54% percutaneous coronary intervention, and 46% cardiac surgery. Thirty-day mortality was higher in patients with cardiac comorbidity (6.9% vs. 3.7%, P = 0.008), including the incidence of postoperative cardiac arrest requiring cardiopulmonary resuscitation (3.8% vs. 1.2%, P = 0.001) and myocardial infarction (1.7% vs. 0.4%, P = 0.011). Multivariate analysis revealed that functional impairment, older age, and malnutrition, but not cardiac comorbidity, were significant predictors of 30-day mortality. However, prior percutaneous coronary intervention was independently associated with postoperative cardiac arrest (OR 2.999, P = 0.008).

CONCLUSION

While cardiac comorbidity is not a predictor of mortality after major hepatectomy, prior percutaneous coronary intervention is independently associated with postoperative cardiac arrest. Careful patient selection and preoperative optimization is fundamental in patients with prior percutaneous coronary intervention being considered for major hepatectomy as restrictive fluid management and low central venous pressure anesthesia may not be tolerated well by all patients.

Intraoperative monitoring of stroke volume variation versus central venous pressure in laparoscopic liver surgery: a randomized prospective comparative trial

BACKGROUND

Central venous pressure (CVP) is used as a marker of cardiac preload to control intraoperative blood loss in open hepatectomies, while its reliability in laparoscopy is less certain. The aim of this randomized prospective trial was to evaluate the outcome of laparoscopic resections performed with stroke volume variation (SVV) or CVP monitoring.

METHODS

All candidates for laparoscopic liver resection were assigned randomly to SVV or to CVP groups. Outcome was evaluated included conversion rate, cause of conversion, intraoperative blood loss, need for transfusions, length of surgery and postoperative results.

RESULTS

Ninety consecutive patients were enrolled: both SVV and CVP groups included 45 patients each and were comparable in terms of patient and disease characteristics. A reduced rate of conversion was recorded in the SVV compared to the CVP group (6.7% and 17.8% respectively, p = 0.02). Blood loss was lower in the SVV group (150 mL), compared to the CVP group (300 mL, p = 0.04). Morbidity, mortality, length of stay and functional recovery were comparable. On multivariate analysis, lesion location, extent of hepatectomy and type of cardiac preload monitoring were associated significantly to risk of conversion.

CONCLUSION

SVV monitoring in laparoscopic liver surgery improves intraoperative outcome, thus enhancing the benefits of the minimally-invasive approach and fast-track protocols.

High Stroke Volume Variation Method by Mannitol Administration Can Decrease Blood Loss During Donor Hepatectomy

Optimal fluid management to reduce blood loss during donor hepatectomy is important for maximizing donor safety. Mannitol can induce osmotic diuresis, helping prevent increased intravascular volume status. We therefore evaluated the effect of high stroke volume variation (SVV) method by mannitol administration and fluid restriction on blood loss during donor hepatectomy.In this prospective study, 64 donors scheduled for donor right hepatectomy were included and allocated into 2 groups. In group A, the SVV value of each patient was maintained at 10% to 20% during hepatic resection with 0.5 g/kg mannitol administration and fluid restriction at a rate of 2 to 4 mL/kg/h. In group B, the SVV value was maintained at <10% by fluid administration at a rate of 6 to 10 mL/kg/h without diuretic administration during surgery. Intraoperative blood loss was estimated by the loss of red cell mass. Surgeon satisfaction scores and postoperative outcomes, including acute kidney injury, abnormal chest radiographic findings, and hospital stay duration, were also assessed.SVV during hepatectomy was significantly higher in group A than in group B (11.0 ± 1.7 vs 6.5 ± 1.1, P < 0.001). The red cell mass loss was significantly lower in group A than in group B (145.4 ± 107.6 vs 307.9 ± 110.7 mL, P < 0.001). Surgeon satisfaction scores were higher in group A than in group B (2.8 ± 0.5 vs 2.0 ± 0.6, P < 0.001). The incidence of acute kidney injury, abnormal chest radiographic findings, and duration of hospital stay did not significantly differ between the 2 groups.Maintenance of high SVV by mannitol administration is effective and safe for reducing blood loss during donor hepatectomy.

Fluid management in living donor hepatectomy: Recent issues and perspectives

The importance of the safety of healthy living liver donors is widely recognized during donor hepatectomy which is associated with blood loss, transfusion, and subsequent post-operative morbidity. Although the low central venous pressure (CVP) technique can still be effective, it may not be advantageous concerning the safety of healthy donors undergoing hepatectomy. Emerging evidence suggests that stroke volume variation (SVV), a simple and useful index for fluid responsiveness and preload status in various clinical situations, can be applied as a guide for fluid management to reduce blood loss during living donor hepatectomy. Synthetic colloid solutions are also associated with serious adverse events such as the use of renal replacement therapy and transfusion in critically ill or septic patients. However, it is uncertain whether the intra-operative use of colloid solution is associated with similarly adverse effects in patients undergoing living donor hepatectomy. In this review article we discuss the recent issues regarding the low CVP technique and the high SVV method, i.e., maintaining 10%-20% of SVV, for fluid management in order to reduce blood loss during living donor hepatectomy. In addition, we briefly discuss the effects of intra-operative colloid or crystalloid administration for surgical rather than septic or critically ill patients.

Effect of stroke volume variation-directed fluid management on blood loss during living-donor right hepatectomy: a randomised controlled study

Reducing blood loss is beneficial in living liver donor hepatectomy. Although it has been suggested that maintaining a low central venous pressure is important, it is known that low stroke volume variation may be associated with increased blood loss. Therefore, we compared the effect on blood loss of 40 patients randomly assigned to a high stroke volume variation group (maintaining 10-20% of stroke volume variation) vs 38 patients in a control group (maintaining < 10% stroke volume variation) during living-donor right hepatectomy. Mean (SD) blood loss during donor hepatectomy was significantly lower in the high stroke volume variation group than in the control group: 476 (131) ml vs 836 (341) ml, respectively (p < 0.001). Blood pressure and peri-operative laboratory values did not differ between the two groups. However, in the high stroke volume variation group, central venous pressure values were also significantly lower. We were unable to disentangle the effects of stroke volume variation and central venous pressure, but our results confirm that the two together appear beneficial.

Intraoperative circulatory management using the FloTrac™ system in laparoscopic liver resection

INTRODUCTION

Several studies have shown that maintenance of the central venous pressure at a low level during liver surgery is effective for intraoperative management. However, others have suggested that stroke volume variation (SVV) may be a better predictor of fluid responsiveness than central venous pressure. The purpose of this study is to conduct a new type of circulatory management using the FloTrac(TM) system in laparoscopic liver resection and to evaluate specific fluctuations in SVV.

METHODS

Of the laparoscopic liver resections that we performed between March 2012 and December 2013, we used the FloTrac system for intraoperative circulatory management in 21 cases. We analyzed the data, mainly the average value of SVV.

RESULTS

The average SVV value during liver transection was 5.2%-24.6% (mean, 17.0%), and 18 cases (86%) exceeded the conventional cut-off value (13%). The average SVV value was 4.3%-18.2% (mean, 9.7%) when pneumoperitoneum was not in effect, whereas it was 7.3% greater on average during liver transection (mean, 17.0%). No perioperative complications developed.

CONCLUSION

The average SVV value during laparoscopic liver transection (mean, 17.0%) exceeded the conventional cut-off value, but in this study, no perioperative complications developed, which enabled safe management. We might be able to manage appropriate fluid control using FloTrac system in patients with laparoscopic liver resection. Therefore, it is necessary to set the target SVV and conduct prospective trials to verify the safety margin for intraoperative management in the future.

Review of anesthesia in liver transplantation

Liver transplantation (LT) is a well-accepted treatment modality of many end-stage liver diseases. The main issue in LT is the shortage of deceased donors to accommodate the needs of patients waiting for such transplants. Live donors have tremendously increased the pool of available liver grafts, especially in countries where deceased donors are not common. The main ethical concern of this procedure is the safety of healthy donors, who undergo a major abdominal surgery not for their own health, but to help cure others. The first part of the review concentrates on live donor selection, preanesthetic evaluation, and intraoperative anesthetic care for living liver donors. The second part reviews patient evaluation, intraoperative anesthesia monitoring, and fluid management of the recipient. This review provides up-to-date information to help improve the quality of anesthesia, and contribute to the success of LT and increase the long-term survival of the recipients.

Stroke volume variation in hepatic resection: a replacement for standard central venous pressure monitoring

BACKGROUND

Central venous pressure (CVP) is the standard method of volume status evaluation during hepatic resection. CVP monitoring requires preoperative placement of a central venous catheter (CVC), which can be associated with increased time, cost, and adverse events. Stroke volume variation (SVV) is a preload index that can be used to predict an individual's fluid responsiveness through an existing arterial line. The purpose of this study was to determine if SVV is as safe and effective as CVP in measuring volume status during hepatic resection.

METHODS

Two cohorts of 40 consecutive patients (80 total) were evaluated during hepatic resection between December 2010 and August 2012. The initial evaluation group of 40 patients had continuous CVP monitoring and SVV monitoring performed simultaneously to establish appropriate SVV parameters for hepatic resection. A validation group of 40 patients was then monitored with SVV alone to confirm the accuracy of the established SVV parameters. Type of hepatic resection, transection time, blood loss, complications, and additional operative and postoperative factors were collected prospectively. SVV was calculated using the Flotrac™/Vigileo™ System.

RESULTS

The evaluation group included 40 patients [median age 62 (29-82) years; median body mass index (BMI) 27.7 (16.5-40.6)] with 18 laparoscopic, 22 open, and 24 undergoing major (≥3 segments) hepatectomy. Median transection times were 43 (range 20-65) min, median blood loss 250 (range 20-950) cc, with no Pringle maneuver utilized. In this evaluation group, a CVP of -1 to 1 significantly correlated to a SVV of 18-21 (R (2) = 0.85, p < 0.001). The validation group included 40 patients [median age 61 (35-78) years; median BMI 28.1 (17-41.2)], with 24 laparoscopic, 16 open, and 33 undergoing major hepatectomy. Using a SVV goal of 18 to 21, median transection time was 55 (25-78) min, median blood loss of 255 (range 100-1,150) cc, again without the use of a Pringle maneuver.

CONCLUSIONS

SVV can be used safely as an alternative to CVP monitoring during hepatic resection with equivalent outcomes in terms of blood loss and parenchymal transection time. Using SVV as a predictor of fluid status could prove to be advantageous by avoiding the need for CVC insertion and therefor eliminating the risk of CVC related complications in patients undergoing hepatic resection.

Goal-directed fluid optimization based on stroke volume variation and cardiac index during one-lung ventilation in patients undergoing thoracoscopy lobectomy operations: a pilot study

OBJECTIVES

This pilot study was designed to utilize stroke volume variation and cardiac index to ensure fluid optimization during one-lung ventilation in patients undergoing thoracoscopic lobectomies.

METHODS

Eighty patients undergoing thoracoscopic lobectomy were randomized into either a goal-directed therapy group or a control group. In the goal-directed therapy group, the stroke volume variation was controlled at 10%±1%, and the cardiac index was controlled at a minimum of 2.5 L.min-1.m-2. In the control group, the MAP was maintained at between 65 mm Hg and 90 mm Hg, heart rate was maintained at between 60 BPM and 100 BPM, and urinary output was greater than 0.5 mL/kg-1/h-1. The hemodynamic variables, arterial blood gas analyses, total administered fluid volume and side effects were recorded.

RESULTS

The PaO2/FiO2-ratio before the end of one-lung ventilation in the goal-directed therapy group was significantly higher than that of the control group, but there were no differences between the goal-directed therapy group and the control group for the PaO2/FiO2-ratio or other arterial blood gas analysis indices prior to anesthesia. The extubation time was significantly earlier in the goal-directed therapy group, but there was no difference in the length of hospital stay. Patients in the control group had greater urine volumes, and they were given greater colloid and overall fluid volumes. Nausea and vomiting were significantly reduced in the goal-directed therapy group.

CONCLUSION

The results of this study demonstrated that an optimization protocol, based on stroke volume variation and cardiac index obtained with a FloTrac/Vigileo device, increased the PaO2/FiO2-ratio and reduced the overall fluid volume, intubation time and postoperative complications (nausea and vomiting) in thoracic surgery patients requiring one-lung ventilation.

Is stroke volume variation a useful preload index in liver transplant recipients? A retrospective analysis

BACKGROUND

The right ventricular end-diastolic volume index (RVEDVI) is a good indicator of preload in patients undergoing liver transplantation. Although dynamic indices, such as stroke volume variation (SVV), have been used as reliable indicators in predicting fluid responsiveness, the evaluation of the relationship between SVV and direct preload status is limited. We investigated the relationship between SVV and RVEDVI, and tested the cutoff value of SVV to predict RVEDVI during liver transplantation.

METHODS

A total of 150 data pairs in 30 living donor liver transplant recipients were retrospectively investigated. Hemodynamic parameters, including SVV and RVEDVI were obtained from each patient at the 5 specific time points. Linear regression and receiver operating characteristic (ROC) curve analyses were performed.

RESULTS

The SVV significantly correlated with the RVEDVI (r = -0.616, P < 0.001). Cutoff values for the upper and lower tertiles of RVEDVI were 157 mL/m(2) and 128 mL/m(2), respectively. Tertile analysis indicated that upper tertile of RVEDVI had a significantly lower SVV than the middle tertile (median; 5% vs 8%, P < 0.05), and middle tertile of RVEDVI had a significantly lower SVV than the lower tertile (median; 8% vs 11%, P < 0.05). A 6% cutoff value of SVV estimated the upper tertile RVEDVI (>157 mL/m(2)) with the area under the curve of ROC curve of 0.832. A 9% cutoff value of SVV estimated the lower tertile RVEDVI (<128 mL/m(2)) with the area under the curve of ROC curve of 0.792.

CONCLUSION

SVV may be a valuable estimator of RVEDVI in patients undergoing liver transplantation.