Effect of subclavian vein diameter combined with perioperative fluid therapy on preventing post-induction hypotension in patients with ASA status I or II.

BACKGROUND: Perioperative hypotension is frequently observed following the initiation of general anesthesia administration, often associated with adverse outcomes. This study assessed the effect of subclavian vein (SCV) diameter combined with perioperative fluid therapy on preventing post-induction hypotension (PIH) in patients with lower ASA status. METHODS: This two-part study included patients aged 18 to 65 years, classified as ASA physical status I or II, and scheduled for elective surgery. The first part (Part I) included 146 adult patients, where maximum SCV diameter (dSCVmax), minimum SCV diameter (dSCVmin), SCV collapsibility index (SCVCI) and SCV variability (SCVvariability) assessed using ultrasound. PIH was determined by reduction in mean arterial pressure (MAP) exceeding 30% from baseline measurement or any instance of MAP < falling below 65 mmHg for ≥ a duration of at least 1 min during the period from induction to 10 min after intubation. Receiver Operating Characteristic (ROC) curve analysis was employed to determine the predictive values of subclavian vein diameter and other relevant parameters. The second part comprised 124 adult patients, where patients with SCV diameter above the optimal cutoff value, as determined in Part I study, received 6 ml/kg of colloid solution within 20 min before induction. The study evaluated the impact of subclavian vein diameter combined with perioperative fluid therapy by comparing the observed incidence of PIH after induction of anesthesia. RESULTS: The areas under the curves (with 95% confidence intervals) for SCVCI and SCVvariability were both 0.819 (0.744-0.893). The optimal cutoff values were determined to be 45.4% and 14.7% (with sensitivity of 76.1% and specificity of 86.7%), respectively. Logistic regression analysis, after adjusting for confounding factors, demonstrated that both SCVCI and SCVvariability were significant predictors of PIH. A threshold of 45.4% for SCVCI was chosen as the grouping criterion. The incidence of PIH in patients receiving fluid therapy was significantly lower in the SCVCI ≥ 45.4% group compared to the SCVCI < 45.4% group. CONCLUSIONS: Both SCVCI and SCVvariability are noninvasive parameters capable of predicting PIH, and their combination with perioperative fluid therapy can reduce the incidence of PIH.

The impact of intra- and postoperative fluid balance in pancreatic surgery - A retrospective cohort study.

BACKGROUND/OBJECTIVES: The aim of this study was to evaluate the impact of perioperative fluid administration in pancreatic surgery. METHODS: Patients who underwent pancreatic resections were identified from our institution's prospectively maintained database. Fluid balances were recorded intraoperatively and at 24hr postoperatively. Patients were stratified into tertiles of fluid administration (low, medium, high). Adjusted multivariable analysis was performed and outcome measures were postoperative complications. RESULTS: A total of 211 patients were included from 2012 to 2017. Complication rates were POPF(B/C) 19.4%, DGE(B/C) 14.7%, PPH(C) 10.0% and CDC ≥ IIIb 26.1%. In multivariable analysis, high perioperative fluid balance was an independent risk factor associated with POPF (OR = 10.5, 95%CI 2.7-40.7, p = .001), CDC (OR = 2.5, 95%CI 1.2-5.3, p < .002), DGE (OR = 2.3, 95%CI 1.0-5.2, p = .017), PPH (OR = 6.7 95%CI 2.2-20.0, p = .038) and reoperation (OR = 3.1, 95%CI 1.6-6.2, p = .006). In multivariable analysis with intraoperative and postoperative fluid balances as separate predictors, intraoperative (OR = 2,5, 95%CI 1.2-5.5, p = .04) and postoperative fluid balance (OR = 2.5, 95%CI 1.2-5.5, p = .02) were predictors of POPF. Postoperative fluid balance was the only predictor for mortality (OR = 4.5, 95%CI 1.0-18.9, p = .041) and predictor for CDC (OR = 2.0, 95%CI 1.0-4.0, p = .043) and OHS days (OR = 6.9, 95%CI 0.03-13.7, p = .038). CONCLUSIONS: High postoperative fluid balance in particular is associated with postoperative morbidity. Maintaining a fluid-restrictive strategy postoperatively should be recommended for patients undergoing pancreatic surgery.

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

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

Effects of 24-hour postoperative intravenous fluid on postoperative outcomes after lobectomy: a retrospective observational study.

Background: Postoperative fluid management plays a key role in providing adequate tissue perfusion, stabilizing hemodynamics, and reducing morbidities related to hemodynamics. This study evaluated the dose-response relationship between postoperative 24-hour intravenous fluid volume and postoperative outcomes in patients with non-small cell lung cancer (NSCLC) undergoing video-assisted thoracoscopic surgery (VATS) lobectomy. Methods: A retrospective analysis of adult patients with NSCLC undergoing VATS lobectomy between May 2016 and April 2017 was performed. The primary exposure variable was total intravenous crystalloid infusion in the 24-hour postoperative period. The observation outcomes were postoperative pulmonary complications, acute kidney injury (AKI), in-hospital mortality, readmission within 30 days, prolonged hospital stay, postoperative length of stay, and total hospital care costs. Univariate and multivariate analyses were performed. Results: Of the 563 patients, 136 (24.2%) with pulmonary complications were observed. Binary logistics regression showed that, relative to the group with moderate postoperative 24-hour crystalloid infusion, the risk for postoperative pulmonary complications was significantly increased in the restrictive [odds ratio (OR) 1.815, 95% CI: 1.083-3.043; P=0.024] and liberal (OR 2.692, 95% CI: 1.684-4.305; P<0.001) groups. Conclusions: In patients with NSCLC undergoing VATS lobectomy, both restrictive and liberal 24-hour postoperative crystalloid infusions were related to adverse effects on postoperative outcomes and the optimal volume of 24-hour postoperative intravenous crystalloid infusion was 1,080-<1,410 mL.

Effect of perioperative fluid volume restriction on the incidence of complications following pancreaticoduodenectomy.

BACKGROUND: Perioperative fluid restriction has been suggested to reduce morbidity and length of stay. The purpose of this study was to compare the morbidity following pancreaticoduodenectomy (PD) between fluid restriction group and conventional management group. METHODS: Seventy-two patients were enrolled for perioperative fluid restriction of PD. During the operation, main fluid was infused at a rate of less than 8 mL/kg/hr. Until POD#3, 10% dextrose and Hartmann's solution were administered at rates of 40 mL/h and {(1.5*body weight) - 42} mL/h, respectively. The historical control group consisted of 139 patients. We compared the rates of major complication (Clavien-Dindo grade III to V) and clinically relevant postoperative pancreatic fistula (CR-POPF), length of hospital stays (LOS), amount of urine output, and the rate of acute kidney injury (AKI). RESULTS: The rates of major complication (19.0% versus 18.7%; p > 0.999), CR-POPF (15.5% versus 15.1%; p > 0.999), and LOS (19 days [range: 10-52] versus 19 days [range: 11-75]; p = 0.514) were comparable in the study and the control group, respectively. Amount of urine output during the operation and from POD#1 to POD#3 was more than minimal amount (0.5 mL/kg/hr) in the both groups. Incidence rate of AKI in the study group was not higher than the control group (Stage I: 1.7% versus 2.9%, p > 0.999; stage II: 0% versus 1.4%, p > 0.999). CONCLUSION: There was no decrease in incidence of morbidity including POPF following PD with perioperative fluid restriction. Fluid restriction was feasible because it did not reduce urine output and did not increase incidence of AKI.

Intermittent boluses of balanced salt solution for post-operative intravenous hydration following elective major abdominal and thoracic surgery in children.

PURPOSE: Maintenance fluids following major operations in children are typically administered with a continuous rate. We hypothesized that administering fluids as intermittent boluses is more physiologic and could limit post-operative fluid volume, thereby avoiding harmful effects of excess fluid. METHODS: We retrospectively reviewed children aged 1-21 admitted after an elective major abdominal or thoracic operation from 2015 to 2021. We excluded non-elective operations and patients receiving peri-operative enteral or parenteral nutrition. We analyzed total fluid volume at 0-24, 24-48, 48-72, and 72-96 h, time to regular diet and discharge, and end-organ complications. RESULTS: We identified 363 patients, of which 108 received intermittent boluses and 255 continuous fluids. Bolus group patients received significantly less fluid up to 72 h post-operatively with average rates of 0.49 mL/kg/h vs 0.86 mL/kg/h at 0-24 h (p << 0.01), 0.57 mL/kg/h vs 1.46 mL/kg/h at 24-48 h (p << 0.01), and 0.50 vs 0.92 mL/kg/h at 48-72 h (p << 0.01). Additionally, the bolus group maintained adequate urine output, tolerated a regular diet sooner (2.08 days vs 2.51 days; p = 0.0023) and averaged a shorter hospital stay (3.12 vs 4.14 days; p = 0.004). There was no difference in adverse effects between the two groups. CONCLUSION: Utilizing intermittent boluses reduces the volume of maintenance fluids administered and may lead to a faster time to regular diet and discharge. LEVEL OF EVIDENCE: IV. TYPE OF STUDY: Retrospective review.

Changes in arterial blood pressure characteristics following an extrasystolic beat or a fast 50 ml fluid challenge do not predict fluid responsiveness during cardiac surgery.

Prediction of fluid responsiveness is essential in perioperative goal directed therapy, but dynamic tests of fluid responsiveness are not applicable during open-chest surgery. We hypothesised that two methods could predict fluid responsiveness during cardiac surgery based on their ability to alter preload and thereby induce changes in arterial blood pressure characteristics: (1) the change caused by extrasystolic beats and (2) the change caused by a fast infusion of 50 ml crystalloid (micro-fluid challenge). Arterial blood pressure and electrocardiogram waveforms were collected during surgical preparation of the left internal mammary artery in patients undergoing coronary artery bypass surgery. Patients received a fluid challenge (5 ml/kg ideal body weight). The first 50 ml were infused in 10 s and comprised the micro-fluid challenge. Predictor variables were defined as post-ectopic beat changes (compared with sinus beats preceding ectopy) in arterial blood pressure characteristics, such as pulse pressure and systolic pressure, or micro-fluid challenge induced changes in the same blood pressure characteristics. Patients were considered fluid responsive if stroke volume index increased by 15% or more after the full fluid challenge. Diagnostic accuracy was calculated by the area under the receiver operating characteristics curve (AUC). Fifty-six patients were included for statistical analysis. Thirty-one had extrasystoles. The maximal AUC was found for the extrasystolic change in pulse pressure and was 0.70 (CI [0.35 to 1.00]). The micro-fluid challenge method generally produced lower AUC point estimates. Extrasystoles did not predict fluid responsiveness with convincing accuracy in patients undergoing cardiac surgery and changes in arterial waveform indices following a micro-fluid challenge could not predict fluid responsiveness. Given a low number of fluid responders and inherently reduced statistical power, our data does not support firm conclusions about the utility of the extrasystolic method. CLINICAL TRIAL REGISTRATION: Unique identifier: NCT02903316. https://clinicaltrials.gov/ct2/show/NCT02903316?cond=NCT02903316&rank=1 .

Peri-operative approach to esophagectomy: a narrative review from the anesthesiological standpoint.

OBJECTIVE: This review summarizes the peri-operative anesthesiological approaches to esophagectomy considering the best up-to-date, evidence-based medicine, discussed from the anesthesiologist's standpoint. BACKGROUND: Esophagectomy is the only curative therapy for esophageal cancer. Despite the many advancements made in the surgical treatment of this tumour, esophagectomy still carries a morbidity rate reaching 60%. Patients undergoing esophagectomy should be referred to high volume centres where they can receive a multidisciplinary approach to treatment, associated with better outcomes. The anesthesiologist is the key figure who should guide the peri-operative phase, from diagnosis through to post-surgery rehabilitation. We performed an updated narrative review devoted to the study of anesthesia management for esophagectomy in cancer patients. METHODS: We searched MEDLINE, Scopus and Google Scholar databases from inception to May 2021. We used the following terms: "esophagectomy", "esophagectomy AND pre-operative evaluation", "esophagectomy AND protective lung ventilation", "esophagectomy AND hemodynamic monitoring" and "esophagectomy AND analgesia". We considered only articles with abstract written in English and available to the reader. We excluded single case-reports. CONCLUSIONS: Pre-operative anesthesiological evaluation is mandatory in order to stratify and optimize any medical condition. During surgery, protective ventilation and judicious fluid management are the cornerstones of intraoperative "protective anesthesia". Post-operative care should be provided by an intensive care unit or high-dependency unit depending on the patient's condition, the type of surgery endured and the availability of local resources. The provision of adequate post-operative analgesia favours early mobilization and rapid recovery. Anesthesiologist has an important role during the peri-operative care for esophagectomy. However, there are still some topics that need to be further studied to improve the outcome of these patients.

Association between perioperative fluid management and patient outcomes: a multicentre retrospective study.

BACKGROUND: Postoperative complications increase hospital length of stay and patient mortality. Optimal perioperative fluid management should decrease patient complications. This study examined associations between fluid volume and noncardiac surgery patient outcomes within a large multicentre US surgical cohort. METHODS: Adults undergoing noncardiac procedures from January 1, 2012 to December 31, 2017, with a postoperative length of stay ≥24 h, were extracted from a large US electronic health record database. Patients were segmented into quintiles based on recorded perioperative fluid volumes with Quintile 3 (Q3) serving as the reference. The primary outcome was defined as a composite of any complications during the surgical admission and a postoperative length of stay ≥7 days. Secondary outcomes included in-hospital mortality, respiratory complications, and acute kidney injury. RESULTS: A total of 35 736 patients met the study criteria. There was a U-shaped pattern with highest (Q5) and lowest (Q1) quintiles of fluid volumes having increased odds of complications and a postoperative length of stay ≥7 days (Q5: odds ratio [OR] 1.51 [95% confidence interval {CI}: 1.30-1.74], P<0.001; Q1: OR 1.20 [95% CI: 1.04-1.38], P=0.011) compared with Q3. Patients in Q5 had greater odds of more severe acute kidney injury compared with Q3 (OR 1.52 [95% CI: 1.22-1.90]; P<0.001) and respiratory complications (OR 1.44 [95% CI: 1.17-1.77]; P<0.001). CONCLUSIONS: Both very high and very low perioperative fluid volumes were associated with an increase in complications after noncardiac surgery.

[Perioperative fluid management]. / Perioperatives Volumenmanagement.

An appropriate perioperative infusion management is pivotal for the perioperative outcome of the patient. Optimization of the perioperative fluid treatment often results in enhanced postoperative outcome, reduced perioperative complications and shortened hospitalization. Hypovolemia as well as hypervolemia can lead to an increased rate of perioperative complications. The main goal is to maintain perioperative euvolemia by goal-directed therapy (GDT), a combination of fluid management and inotropic medication, to optimize perfusion conditions in the perioperative period; however, perioperative fluid management should also include the preoperative and postoperative periods. This encompasses the preoperative administration of carbohydrate-rich drinks up to 2 h before surgery. In the postoperative period, patients should be encouraged to start per os hydration early and excessive i.v. fluid administration should be avoided. Implementation of a comprehensive multimodal, goal-directed fluid management within an enhanced recovery after surgery (ERAS) protocol is efficient but the exact status of indovodual items remains unclear at present.

Intraoperative and postanesthesia care unit fluid administration as risk factors for postoperative complications in patients with head and neck cancer undergoing free tissue transfer.

BACKGROUND: This study aims to evaluate the impact of perioperative fluid administration, defined as fluid delivered intraoperatively and in the postanesthesia care unit, on postoperative outcomes. METHODS: Medical records of 102 patients with oral cavity squamous cell carcinoma undergoing free flap reconstruction between January 2011 and December 2015 were reviewed. The primary endpoint was development of a postoperative complication according to the Clavien-Dindo classification. Perioperative factors recorded were Washington University Head and Neck Comorbidity Index, operating time, vasopressor use, blood loss, intraoperative fluid, and perioperative fluid. RESULTS: Greater perioperative fluid administration was independently associated with surgical complications, flap complications, overall incidence of any complication, and increased length of stay. Greater intraoperative fluid administration was independently associated with higher rates of surgical complications. Intraoperative delivery of vasopressors was not associated with flap or surgical complications. CONCLUSION: Receiving less perioperative fluid was associated with fewer complications and decreased length of stay.

Postoperative fluid overload is a risk factor for adverse surgical outcome in patients undergoing esophagectomy for esophageal cancer: a retrospective study in 335 patients.

BACKGROUND: Restrictive intraoperative fluid management is increasingly recommended for patients undergoing esophagectomy. Controversy still exists about the impact of postoperative fluid management on perioperative outcome. METHODS: We retrospectively examined 335 patients who had undergone esophagectomy for esophageal cancer at the University Hospital Freiburg between 1996 and 2014 to investigate the relation between intra- and postoperative fluid management and postoperative morbidity after esophagectomy. RESULTS: Perioperative morbidity was 75%, the in-hospital mortality 8%. A fluid balance above average on the operation day was strongly associated with a higher rate of postoperative mortality (21% vs 3%, p < 0.001) and morbidity (83% vs 66%, p = 0.001). Univariate analysis for risk factors for adverse surgical outcome (Clavien ≥ III) identified ASA-score (p = 0.002), smoking (p = 0.036), reconstruction by colonic interposition (p = 0.036), cervical anastomosis (p = 0.017), blood transfusion (p = 0.038) and total fluid balance on the operation day and on POD 4 (p = 0.001) as risk factors. Multivariate analysis confirmed only ASA-score (p = 0.001) and total fluid balance (p = 0.001) as independent predictors of adverse surgical outcome. CONCLUSION: Intra- and postoperative fluid overload is strongly associated with increased postoperative morbidity. Our results suggest restrictive intra- and especially postoperative fluid management to optimize the outcome after esophagectomy.

Excessive intravenous fluid therapy in head and neck cancer surgery.

BACKGROUND: The purpose of this retrospective study was to present our assessment of modifiable perioperative factors for major cardiac and cerebrovascular events (MACCE). METHODS: This study included an unselected cohort of patients with head and neck cancer (n = 456) treated in Turku University Hospital between 1999 and 2008. RESULTS: Perioperative and postoperative univariate predictors of MACCE at 30-day follow-up were: total amount of fluids (during 24 hours) over 4000 mL, any red blood cell (RBC) infusion, treatment in the intensive care unit (ICU), tracheostomy, and microvascular reconstruction surgery. Median time from operation to MACCE was 3 days. Patients receiving >4000 mL of fluids had MACCE more often compared with those receiving <4000 mL (10.8% vs 2.4%; p < .001, respectively). Moreover, every RBC unit transfused or every liter of fluid administered over 4000 mL/24h increased the risk of MACCE 18% per unit/liter, respectively. CONCLUSION: Patients with head and neck cancer receiving excessive intravenous fluid administration perioperatively and postoperatively are at high risk for cardiac complications, especially heart failure. © 2016 Wiley Periodicals, Inc. Head Neck 39: 37-41, 2017.

Efficacy of bioelectrical impedance analysis during the perioperative period in children.

We evaluated the efficacy of bioelectrical impedance analysis (BIA) during the perioperative period by estimating the preoperative and postoperative body fluid status. After obtaining informed consent, we enrolled 100 children (3-12 years of age) scheduled for elective surgeries. All children had been fasted preoperatively. The children's body fluid status was estimated using a BIA machine (InBody S10; Biospace, Korea) in the ward on the afternoon before surgery (baseline), just before surgery and immediately after surgery. The total administered fluid volume during the fasting period, total administered fluid volume during the operation and fasting time were recorded. Continuous data are shown as mean ± standard deviation, and Pearson's correlation analysis was used to assess relationships between the preoperative fluid deficit and intracellular water (ICW)/extracellular water (ECW) changes. The mean fasting period was 13.3 h (range 5.8-19.7 h). A weak positive correlation was shown between the ICW and fluid deficit during the fasting period (Pearson correlation coefficient = 0.254; P = 0.010). A stronger positive correlation was shown between the ECW and fluid deficit during the fasting period (Pearson correlation coefficient = 0.359; P < 0.001). The baseline and postoperative ICW showed a strong positive correlation (Pearson correlation coefficient = 0.992, P < 0.001), as did the baseline and postoperative ECW (Pearson correlation coefficient = 0.990, P < 0.001). Also there was no dehydration and irritability on medical recording preoperatively. BIA may be an alternative method for estimating the perioperative fluid status in children and determining details of fluid administration.

Perioperative clinical and economic outcomes associated with replacing first-generation high molecular weight hydroxyethyl starch (Hextend®) with low molecular weight hydroxyethyl starch (Voluven®) at a large medical center.

BACKGROUND: Several plasma volume expander alternatives exist to enhance intravascular volume status in patients undergoing surgery. The optimal intravascular volume expander in the perioperative setting is currently unknown. Low molecular weight hetastarch, Voluven® (130/0.4), may have a better safety profile than high molecular weight hetastarch, Hextend® (450/0.7). We examined the clinical and cost outcomes of converting from Hextend® to Voluven® in a large tertiary medical center. METHODS: Using a large electronic database, we retrospectively compared two different time periods (2009 and 2010) where the availability of semisynthetic colloids changed. Perioperative and postoperative outcomes including the use of red blood cells (RBC), platelets and coagulation factors, length of stay in the postoperative acute care unit (PACU), intensive care unit and hospital, as well as 30-day and 1-year mortality were compared. In addition, direct acquisition costs of all intraoperative and PACU colloids and crystalloid use were determined. RESULTS: A total of 4,888 adult subjects were compared of which 1,878 received Hextend® (pre-conversion) and 2,759 received Voluven® (post-conversion) during two separate 7-month periods within 1 year apart, with the remainder receiving Plasmanate. The patients were similar in terms of patient demographics, preoperative comorbidities, ASA status, emergency surgery, types of surgery, intraoperative, and PACU times. In unadjusted outcomes, patients in the Hextend® group received more lactated Ringer's than in the Voluven® group (2,220 + 1,312 vs. 1,946 ± 1,097 ml; P < 0.0001). The use of albumin (Plasmanate) was reduced from 10.5% of patients to 1.1% when Voluven® was substituted for Hextend®. Unadjusted outcomes were similar in each group including hospital LOS, percent change from baseline creatinine and receipt of intraoperative and PACU blood product administration. However, overall unadjusted total fluid costs were greater in the Voluven® compared to Hextend® group ($116.7 compared to $59.3; P < 0.001). CONCLUSIONS: Conversion from Hextend® to Voluven® in the perioperative period resulted in decreased albumin use and was not associated with changes in clinical outcomes and short- and long-term mortality. The conversion was associated with decreases in crystalloid use and an increase in colloid use and hence IV fluid acquisition costs in the Voluven® group.

Perioperative fluid balance affects staging of acute kidney injury in postsurgical patients: a retrospective case-control study.

BACKGROUND: Although Acute Kidney Injury Network (AKIN) staging is widely used, it has been suggested that classification using serum creatinine levels, which fluctuate because of fluid balance, is not always appropriate for acute kidney injury (AKI) detection. We hypothesized that some patients are misdiagnosed as having no AKI due to dilution resulting from intraoperative infusion, and have worse outcomes than typical patients with no AKI. METHODS: We retrospectively selected patients who did not fulfill the AKI criteria from those who underwent cardiac surgery and remained in an intensive care unit (ICU) for ≥7 days. The patients were divided into two groups: those with AKI (AKI group) and those without AKI (no-AKI group), classified using serum creatinine levels adjusted for fluid balance during the perioperative period. We compared the characteristics and outcomes of the two groups. RESULTS: After adjustment for serum creatinine, 7 of 26 patients were categorized as having AKI. The AKI group had significantly fewer ventilator-free days during a 28-day period and significantly longer ICU stays than the no-AKI group (5.86 ± 10.0 days vs. 15.6 ± 9.71 days, respectively, P = 0.050; 36.4 ± 20.6 days vs. 14.9 ± 10.7 days, respectively, P = 0.033). CONCLUSION: Adjustment of creatinine level for perioperative fluid balance could improve the accuracy of AKI diagnosis after cardiac surgery.

The Effect of Routine Maintenance Intravenous Therapy on Hemoglobin Concentration and Hematocrit during Anesthesia in Adults.

OBJECTIVE: To investigate the decrease in hemoglobin concentration and hematocrit during elective surgery. METHODS: This was a prospective study being performed in Nemazee Hospital of Shiraz University of Medical Sciences. We included a total of 50 American Society of Anesthesiology (ASA) I and II patients undergoing elective minor surgeries. Perioperative fluid administration was performed for all the patients and hemoglobin and hematocrit levels were measured three times: Once before the operation, once one hour after start of operation and once in the recovery room. Values were compared using paired sample t-test. RESULTS: The mean age of the patients and controls was 39.66 ± 8.27 years. Hemoglobin level decreases significantly after one hour (p<0.001) and after the end of operation (p<0.001). In the same way hematocrit level was decreased significantly after one hour (p<0.001) and after the end of operation (p<0.001). CONCLUSION: In this patient population undergoing elective minor operations, there was significant decrease in the hemoglobin and hematocrit levels in response to the IV fluids administration.