Positive Intraoperative Fluid Balance Research Articles

Association between intraoperative fluid management and post-operative acute kidney injury: A single-center observational study

Background: Post-operative acute kidney injury (AKI) poses significant risks. Identifying intraoperative determinants is crucial for enhancing patient outcomes and tailoring surgical interventions. Aims and Objectives: This study aimed to investigate the onset of post-operative AKI in patients subjected to various surgical interventions and identify potential intra-operative determinants. Materials and Methods: In this observational investigation conducted at our institution, 100 patients who underwent diverse surgical procedures were included in the study. AKI diagnosis was based on the kidney disease: improving global outcomes guidelines. The parameters assessed encompassed patient demographics, intraoperative fluid management, surgical and anesthetic durations, and post-operative AKI incidence. Determinants of AKI were identified using multivariate logistic regression. Results: The cohort comprised 58% males, with a mean age of 65±12 years. Key comorbidities included hypertension (42%), diabetes mellitus (28%), chronic kidney disease (15%), and cardiovascular disease (20%). Intraoperatively, the average fluid volume administered was 2.5 ± 0.8 L. Fluid management primarily included balanced crystalloids (70%), followed by normal saline (20%), and colloids (10%). Anesthesia was maintained for an average of 3.5 ± 1.2 h. Post-surgery, 15% of the patients developed AKI. A detailed evaluation revealed a strong association between positive intraoperative fluid balance and AKI onset. The statistical analysis pinpointed elevated intraoperative fluid balance (odds ratio: 5.89; 95% confidence interval [CI]: 1.72–20.15; P=0.004) and extended anesthesia duration (odds ratio: 2.12; 95% CI: 1.01–4.47; P=0.046) as significant predictors. Conclusion: AKI onset post-surgery is closely tied to intraoperative factors, notably fluid balance, and anesthesia duration. This underscores the importance of personalized fluid management and vigilant post-operative renal function monitoring to mitigate AKI risks.

Acute Kidney Injury After Large Ventral Hernia Repair Requiring Transversus Abdominis Release.

Acute kidney injury (AKI) is a known postoperative complication of open ventral hernia repair contributing to increased costs, hospital length of stay, and mortality. The aim of this study was to identify whether the muscle injury that occurs in a posterior separation of components via transversus abdominis release (TAR) contributes to a higher incidence of postoperative AKI. A retrospective cohort study of patients who underwent open retrorectus ventral hernia repair with and without TAR at a single institution between 2012 and 2019 was performed. Patients who underwent a separation of components via either unilateral or bilateral transversus abdominis release were compared to those who did not undergo TAR as part of their hernia repair (non-TAR). The outcome of interest was the development of postoperative AKI. Acute kidney injury was defined as an increase in creatinine of greater than 50% of the preoperative baseline. Univariate and multivariate analyses were performed to determine the influence of TAR on the development of AKI. There were 523 patients who met inclusion criteria, of which 159 (30.4%) had a TAR as part of their retrorectus hernia repair. No differences were found in preoperative characteristics between the TAR and non-TAR group including age, gender, history of kidney disease, or history of diabetes. By contrast, the TAR group had significantly greater median estimated blood loss (100mL vs 75mL, P < .01), mean positive intraoperative fluid balance (2255mL vs 1887mL, P < .01), and operative duration (321min vs 269min, P < .001). The rate of AKI in the TAR group was 11% (n = 18) vs 6% (n = 23, P = .0503) in the non-TAR group. On multivariate analysis controlling for patient characteristics and intraoperative factors, TAR was the only factor with a significantly increased odds of AKI (OR 1.97, 95% CI 0.994-3.905, P = .0521). In patients with large ventral hernias requiring retrorectus repair, performing a TAR is associated with a nearly 2-fold increase in the development of postoperative AKI. These findings suggest that these patients should be optimized perioperatively with emphasis on fluid resuscitation, limiting nephrotoxic medications and monitoring urine output.

Effect of positive cumulative fluid balance on postoperative complications after living donor liver transplantation: A retrospective analysis.

Background and Aims:Fluid administration during liver transplant (LT) surgery is controversial. Although adverse outcomes following positive intraoperative fluid balance have been reported, studies presenting the influence of cumulative postoperative fluid balance (CFB) on complications following LT are sparse. Patients with chronic liver disease tend to receive more fluid during and after surgery due to their unique physiological disease state. The aim of this study was to evaluate the influence of 48-hour CFB on the development of acute kidney injury (AKI) and pulmonary complications on day 4 after live donor LT.Methods:This retrospective study included 230 patients undergoing live donor LT. The effect of CFB on day 2 on AKI and pulmonary complications was analysed. Chi-square test, Fisher's exact test, samples t-test, Mann-Whitney U-test were used.Results:Bivariate analysis showed a lower graft vs recipient weight ratio (GRWR), sepsis (P < 0.001) and a higher 48-hour CFB after surgery significantly increased the development of AKI. For pulmonary complications, higher Model for End- stage Liver Disease-Na(MELD-Na) score, higher peak arterial lactate, higher 48-hour CFB (P = 0.016) and sepsis (P = 0.003) were found to be statistically significant. Upon multivariate analysis, CFB at 48 hours was significantly higher in patients suffering from pulmonary complications, and GRWR and sepsis were significant for AKI. For every one litre increase in CFB on day 2, the odds of pulmonary complications increased by 37%.Conclusion:A more positive CFB on day 2 increased the development of pulmonary complications and lower GRWR and sepsis increased the development of AKI.

Postoperative complications after minimally invasive esophagectomy in the prone position: any anesthesia-related factor?

To evaluate the incidence of postoperative complications arising within 30 days of minimally invasive esophagectomy in the prone position with total lung ventilation and their relationship with 30-day and 1-year mortality. Secondary outcomes included possible anesthesia-related factors linked to the development of complications. The study is a retrospective single-center observational study at the Anesthesia and Surgical Department of a tertiary care center in the northeast of Italy. Patients underwent cancer resection through esophagectomy in the prone position without one-lung ventilation. We included 110 patients from January 2010 to December 2017. A total of 54% of patients developed postoperative complications that increased mortality risk at 1 year of follow-up. Complications postponed first oral intake and delayed patient discharge to home. Positive intraoperative fluid balance was related to increased mortality and the risk to develop postoperative complications. C-reactive protein at third postoperative day may help detect complication onset. Complication onset has a great impact on mortality after esophagectomy. Some anesthesia-related factors, mainly fluid balance, may be associated with postoperative mortality and morbidity. These factors should be carefully taken into account to obtain better outcomes after esophagectomy in the prone position without one-lung ventilation.

Intraoperative Fluid Balance and Perioperative Outcomes After Aortic Valve Surgery

The effect of intraoperative fluid balance on postoperative acute kidney injury (AKI) in cardiac surgical patients is poorly defined. In this retrospective study of patients undergoing aortic valve replacement for aortic stenosis, the primary outcome of interest was postoperative AKI. Secondary outcomes were postoperative fluid balance, cardiac index, vasopressor use, hospital-free days, stroke, myocardial infarction, hospital readmission, and 30- and 90-day mortality. A total of 2327 patients were analyzed. Positive intraoperative fluid balance was associated with lower odds of AKI; the lowest odds were in the 20- to 39-mL/kg group (odds ratio, 0.56; 95% confidence interval, 0.38-0.81; P= .002). Positive intraoperative fluid balance was associated with a lower postoperative fluid balance. Increased ultrafiltration volume was associated with increased postoperative fluid resuscitation and vasopressor use. AKI was associated with increased 30- and 90-day mortality. Increased fluid balance was associated with increased odds of myocardial infarction and 30-day mortality. Increased ultrafiltration volume was associated with increased odds of 30- and 90-day mortality. In patients who underwent aortic valve replacement for aortic stenosis, positive intraoperative fluid balance was associated with decreased odds of AKI. Patients developing AKI had increased 30- and 90-day mortality. Although the overall incidence was low, increased intraoperative fluid balance was associated with myocardial infarction and 30-day mortality, whereas increased ultrafiltration volume was associated with 30- and 90-day morality. Prospective studies are needed to better define proper intraoperative fluid management in patients undergoing cardiac surgery.

Bio-electrical impedance analysis for perioperative fluid evaluation in open major abdominal surgery

Water retention and intercompartmental redistribution occur frequently in association with adverse postoperative outcomes, yet the available strategies for non-invasive assessment are limited. One such approach for evaluating body water composition in various circumstances is bio-electrical impedance analysis (BIA). This study aims to appraise the usefulness of the Body Composition Monitor (BCM, Fresenius Medical Care, Germany) in assessing body fluid composition and intercompartmental shifts before and after open major abdominal surgery. This prospective, clinician blinded observational study enrolled all the patients scheduled consecutively for elective major open abdominal surgery during a 1-year period starting from January 1st, 2016. BIA parameters—total body water (TBW), extracellular water (ECW), intracellular water (ICW), absolute fluid overload (AFO), and relative fluid overload (RFO) were measured before and after surgery. The results were compared with fluid balance and outcome parameters such as organ dysfunction, ICU-and hospital length of stay (-LOS). The study population included 71 patients aged 60.2 ± 12 of whom 60.6% men and with a BMI of 26.3 ± 5.1 kg/m2. Postoperative acute kidney injury, respiratory dysfunction, and infections occurred in 14.0%, 19.7% and 28.1% of cases, respectively. The median LOS in ICU was 20 h and the hospital-LOS was 10 days. Positive intraoperative fluid balance (2.4 ± 1.0 L) resulted in a significant increase of TBW (1.4 ± 2.4 L) and of ECW (1.4 ± 1.2 L). Intraoperative fluid balance significantly correlated with TBW change (r = 0.23, p = 0.04) and with AFO change (r = 0.31, p < 0.01). A significant correlation was found between pre- and postoperative AFO and RFO on one hand, and ICU-LOS on the other. BIA may be a useful tool for the perioperative assessment of volume status.

Prevention of the Osmotic Demyelination Syndrome After Liver Transplantation: A Multidisciplinary Perspective.

The osmotic demyelination syndrome (ODS) is a serious neurologic condition that occurs in the setting of rapid correction of hyponatremia. It presents with protean manifestations, from encephalopathy to the "locked-in" syndrome. ODS can complicate liver transplantation (LT), and its incidence may increase with the inclusion of serum sodium as a factor in the Mayo End-Stage Liver Disease score. A comprehensive understanding of risk factors for the development of ODS in the setting of LT, along with recommendations to mitigate the risk of ODS, are necessary. The literature to date on ODS in the setting of LT was reviewed. Major risk factors for the development of ODS include severe pretransplant hyponatremia (serum sodium [SNa] < 125 mEq/L), the magnitude of change in SNa pre- versus posttransplant, higher positive intraoperative fluid balance, and the presence of postoperative hemorrhagic complications. Strategies to reduce the risk of ODS include correcting hyponatremia pretransplant via fluid restriction and/or ensuring an appropriate rate of increase from the preoperative SNa via close attention to fluid and electrolyte management both during and after surgery. Multidisciplinary management involving transplant hepatology, nephrology, neurology, surgery, and anesthesiology/critical care is key to performing LT safely in patients with hyponatremia.

Isoflurane in Contrast to Propofol Promotes Fluid Extravasation during Cardiopulmonary Bypass in Pigs

A highly positive intraoperative fluid balance should be prevented as it negatively impacts patient outcome. Analysis of volume-kinetics has identified an increase in interstitial fluid volume after crystalloid fluid loading during isoflurane anesthesia. Isoflurane has also been associated with postoperative hypoxemia and may be associated with an increase in alveolar epithelial permeability, edema formation, and hindered oxygen exchange. In this article, the authors compare fluid extravasation rates before and during cardiopulmonary bypass (CPB) with isoflurane- versus propofol-based anesthesia. Fourteen pigs underwent 2 h of tepid CPB with propofol (P-group; n = 7) or isoflurane anesthesia (I-group; n = 7). Fluid requirements, plasma volume, colloid osmotic pressures in plasma and interstitial fluid, hematocrit levels, and total tissue water content were recorded, and fluid extravasation rates calculated. Fluid extravasation rates increased in the I-group from the pre-CPB level of 0.27 (0.13) to 0.92 (0.36) ml·kg·min, but remained essentially unchanged in the P-group with significant between-group differences during CPB (pb = 0.002). The results are supported by corresponding changes in interstitial colloid osmotic pressure and total tissue water content. During CPB, isoflurane, in contrast to propofol, significantly contributes to a general increase in fluid shifts from the intravascular to the interstitial space with edema formation and a possible negative impact on postoperative organ function.

Randomized trial of hematocrit 25% versus 35% during hypothermic cardiopulmonary bypass in infant heart surgery

We previously reported that postoperative hemodynamics and developmental outcomes were better among infants randomized to a higher hematocrit value during hypothermic cardiopulmonary bypass. However, worse outcomes were concentrated in patients with hematocrit values of 20% or below, and the benefits of hematocrit values higher than 25% were uncertain. We compared perioperative hemodynamics and, at 1 year, developmental outcome and brain magnetic resonance imaging in a single-center, randomized trial of hemodilution to a hematocrit value of 25% versus 35% during hypothermic radiopulmonary bypass for reparative heart surgery in infants undergoing 2-ventricle repairs without aortic arch obstruction. Among 124 subjects, 56 were assigned to the lower-hematocrit strategy (24.8% +/- 3.1%, mean +/- SD) and 68 to the higher-hematocrit strategy (32.6% +/- 3.5%). Infants randomized to the 25% strategy, compared with the 35% strategy, had a more positive intraoperative fluid balance (P = .007) and lower regional cerebral oxygen saturation at 10 minutes after cooling (P = .04) and onset of low flow (P = .03). Infants with dextro-transposition of the great arteries in the 25% group had significantly longer hospital stay. Other postoperative outcomes, blood product usage, and adverse events were similar in the treatment groups. At age 1 year (n = 106), the treatment groups had similar scores on the Psychomotor and Mental Development Indexes of the Bayley Scales; both groups scored significantly worse than population norms. Hemodilution to hematocrit levels of 35% compared with those of 25% had no major benefits or risks overall among infants undergoing 2-ventricle repair. Developmental outcomes at age 1 year in both randomized groups were below those in the normative population.

The effect of hematocrit during hypothermic cardiopulmonary bypass in infant heart surgery: Results from the combined Boston hematocrit trials

Two randomized trials of hematocrit strategy during hypothermic cardiopulmonary bypass in infant heart surgery have been performed. The first suggested worse outcomes were concentrated in patients with lower hematocrit levels (approximately 20%), whereas the second suggested there was little benefit to increasing the hematocrit level above 25%. The form of the relationship between continuous hematocrit levels and outcomes requires further study. In the two trials, 271 infants who underwent biventricular repair not involving the aortic arch were enrolled. Analysis was undertaken of the effects of hematocrit level, as a continuous variable, at the onset of low-flow cardiopulmonary bypass. Psychomotor Development Index scores at age 1 year varied nonlinearly with hematocrit levels, with increasing scores up to 23.5% hematocrit (P < .001) and a plateau effect beyond 23.5% (P = .42), based on a piecewise linear model. Lower hematocrit levels were associated with more positive intraoperative fluid balance (P < .001 for linear trend) and marginally associated with higher serum lactate levels at 60 minutes after bypass (P = .08 for linear trend), but not with blood products given, nadir of cardiac index in the first 24 hours, or Mental Development Index scores. A hematocrit level at the onset of low-flow cardiopulmonary bypass of approximately 24% or higher is associated with higher Psychomotor Development Index scores and reduced lactate levels. Because the effects of hemodilution may vary according to diagnosis, age at operation, bypass variables such as pH strategy and flow rate, and other perioperative factors, this study cannot ascertain a universally "safe" hemodilution level.

Highly positive intraoperative fluid balance during cardiac surgery is associated with adverse outcome.

Hemodilution and increase in capillary permeability occurring with cardiopulmonary bypass (CPB) impose a risk for tissue edema and blood transfusion that may result in an increased complication rate after coronary artery bypass grafting (CABG). Of the 1280 consecutive patients undergoing isolated on-pump CABG, total fluid balance at the end of the operation was less than or equal to 500 mL in 1155 (Group 1) and more than 500 mL in 125 (Group 2). During CPB, blood was added to the reservoir only when the hematocrit fell to 17% or less and crystalloid solution only when the pump flow index fell below 2.0 L/min/m2. Anesthetic, surgical, and postoperative management and diagnoses were the same in all patients, and a single surgical and anesthesia team performed all operations. No patient was excluded from the study. Hypertension, diabetes, chronic obstructive pulmonary disease, New York Heart Association (NYHA) Class III-IV, use of angiotensin converting enzyme (ACE) inhibitors, chronic renal failure, and female gender were the significant preoperative risk factors for increased volume replacement during CPB. The groups were similar in body mass index, preoperative hematocrit values, total fluid balance in the intensive care unit (ICU), and total chest tube output. However, red blood cells' transfusion rate, readmission rate to the ICU and length of hospital stay were significantly higher in Group 2 patients. Multiple logistic regression revealed that age > 70 years (p < 0.001, Odds Ratio (OR): 2, 95% CI: 1.4-2.8), and total fluid balance > 500 mL at the end of the operation (p < 0.01, OR: 2.2, 95% CI: 1.5-3.2) were the predictors of increased length of stay. For transfusion of red blood cells, age > 70 years (p < 0.0001, OR: 2.3, 95% CI: 1.6-3.3), and total fluid balance > 500 mL at the end of the operation (p < 0.001, OR: 2, 95% CI: 1.3-2.9) were the only significant risk factors. This study suggests that intraoperative volume overload increases blood transfusion and length of hospital stay in patients undergoing CABG.

Perfusing and ventilating the patient’s lungs during bypass ameliorates the increase in extravascular thermal volume after coronary bypass grafting

Background To test the hypothesis that bilateral extracorporeal circulation (ECC) (Drew technique) ameliorates the increase in extravascular thermal volume (ETV) observed after conventional cardiopulmonary bypass (CPB) in patients undergoing coronary artery bypass grafting. Methods Thirty-four consecutive patients underwent either bilateral ECC (n = 24, additional cannulation of pulmonary artery and left atrium and lungs perfused and ventilated during bypass) or conventional CPB (n = 10, right atrial and aortic cannulation, lungs statically inflated to 4 mbar (0.41 cm H 2O) with oxygen, 500 mL/min). Determinations of ETV (thermodye dilution technique) and intraoperative fluid balance were made before surgery, at the end of surgery, and 4 hours thereafter. In addition, interleukin (IL)-8, thromboxane B2 (TxB 2), and endothelin (ET)-1 concentrations were measured in the right atrium and pulmonary vein at specified time points. Results Comparisons of ETV made at the start of surgery, after aortic declamping, and after termination of ECC, respectively, revealed an increase from 4.8 ± 0.2 mL/kg (mean ± SEM) to 6.7 ± 0.4 mL/kg, and 6.3 ± 0.3 mL/kg with conventional CPB but ETV remained unchanged at 5.2 ± 0.3 mL/kg, 5.1 ± 0.2 mL/kg, and 4.9 ± 0.3 mL/kg with bilateral ECC. Priming volume (1,580 ± 10 mL versus 2,213 ± 77 mL, p < 0.001) and intraoperative fluid balance (+1,955 ± 233 mL versus +2,654 ± 210 mL, p < 0.05) were less with conventional CPB. Concentrations of IL-8, TxB 2, and ET-1 were not different between groups. Conclusions Despite a significantly greater prime volume and a more positive intraoperative fluid balance, ETV did not change with bilateral ECC but increased with conventional CPB. Thus, using the patient’s lungs as an oxygenator during bypass mitigates the increase in extravascular pulmonary fluid.