Nadir Hematocrit Research Articles

Perfusion quality odds (PEQUOD) trial: validation of the multifactorial dynamic perfusion index as a predictor of cardiac surgery-associated acute kidney injury.

The multifactorial dynamic perfusion index was recently introduced as a predictor of cardiac surgery-associated acute kidney injury. The multifactorial dynamic perfusion index was developed based on retrospective data retrieved from the patient files. The present study aims to prospectively validate this index in an external series of patients, through an on-line measure of its various components. Inclusion criteria were adult patients undergoing cardiac surgery with cardiopulmonary bypass. Data collection included preoperative factors and cardiopulmonary bypass-related factors. These were collected on-line using a dedicated monitor. Factors composing the multifactorial dynamic perfusion index are the nadir haematocrit, the nadir oxygen delivery, the time of exposure to a low oxygen delivery, the nadir mean arterial pressure, cardiopulmonary bypass duration, the use of red blood cell transfusions and the peak arterial lactates. Two hundred adult patients were investigated. The multifactorial dynamic perfusion index had a good (c-statistics 0.81) discrimination for cardiac surgery-associated acute kidney injury (any stage) and an excellent (c-statistics 0.93) discrimination for severe patterns (stage 2-3). Calibration was modest for cardiac surgery-associated acute kidney injury (any stage) and good for stage 2-3. The use of vasoconstrictors was an additional factor associated with cardiac surgery-associated acute kidney injury. The multifactorial dynamic perfusion index is validated for discrimination of cardiac surgery-associated acute kidney injury risk. It incorporates modifiable risk factors, and may help in reducing the occurrence of cardiac surgery-associated acute kidney injury.

Effect of geography on the use of ultrafiltration during cardiac surgery with cardiopulmonary bypass.

Ultrafiltration (UF) is a common practice during cardiopulmonary bypass (CPB) where it is used as a blood management strategy to reduce red blood cell (RBC) transfusion, minimize adverse effects of hemodilution, and reduce proinflammatory mediators. However, its clinical utilization has been shown to vary throughout the continents. The purpose of this investigation was to assess the distribution of UF use across the United States. Data on UF use during cardiac surgery was obtained from a national (United States) perfusion database for adult cardiac procedures performed from January 2016 through December 2018. Four geographical regions were established: Northeast (NE), South (SO), Midwest (MW) and West (WE). The primary endpoint was the use of UF with secondary endpoints UF volume, CPB and anesthesia asanguineous volumes, intraoperative allogeneic RBC transfusion, nadir hematocrit and urine output (UO). 92,859 adult cardiac cases from 191 hospitals were reviewed. The NE and the WE had similar usages of UF (59.9% and 59.7% respectively), which were higher than the MW and the SO (38.6% and 34.9%, p < .001). When UF was utilized, the median [IQR] volume removed was highest in the NE (1900 [1200-2800]mL), and similar in all other regions (WE 1500 [850-2400mL, MW 1500 [900-2300]mL and SO 1500 [950-2200]mL, p < .001. Median total UO was lowest in the NE 400 [210,650]mL vs all other regions (p < .001), and remained so when indexed by patient weight and operative time (NE-0.8 [0.5, 1.3]mL/kg/hour, MW-1.1 [0.7, 1.8] mL/kg/hour, SO-1.3 [0.8, 2.0]mL/kg/hour, WE-1.1 [0.7, 1.3]mL/kg/hour, p < .001. Intraoperative RBC transfusion rate was highest in the SO (21.3%) and WE (20.5%), while similar rates seen in the NE (16.2%) and MW (17.6%), p < .001. Across the United States there is geographic variation on the use of UF. Further research is warranted to investigate why these practice variations exist and to better understand and determine their reasons for use.

A novel approach to retrograde autologous priming for infant, pediatric and adult populations undergoing congenital heart surgery.

Retrograde Autologous Priming (RAP) of cardiopulmonary bypass (CPB) circuits is an effective way to reduce prime volume, commonly through the transfer of prime into separate reservoirs or circuit manipulation. We describe a simple and safe technique for RAP without the need for any circuit modifications or manipulations. For this technique, a separate roller pump for ultrafiltration (UF) is used. After adequate heparinization and arterial cannulation, the UF pump is initiated slowly, removing prime through the effluent of the UF, replacing with the patient's blood from the aortic cannula. Once the arterial line and UF circuit are autologous primed, the arterial head displaces reservoir crystalloid toward the UF circuit at a flow rate equal to the UF pump, displacing the crystalloid prime with blood from the UF circuit, autologous priming the boot and oxygenator with blood, crystalloid again being removed by the effluent. After venous cannulation, the venous line prime is replaced with autologous blood, the crystalloid removed by the effluent of the UF circuit via the arterial head. During RAP, if the patient becomes hypovolemic, either autologous volume is transfused back to the patient, or CPB is initiated, without the need for circuitry modifications. The patient population in this sample consisted of 63 patients ranging between 6.1kg and 115.6kg. The smaller the patient, the less blood volume available for RAP and therefore the less prime volume able to be removed. Overall percent removal increases as our patients size increases compared to total circuit volume. This RAP technique is a safe and effective way to achieve a standardized asanguinous prime for many regardless of patient or circuit size in the absence of contraindications such as low starting hematocrit, emergency surgery or physiologic instability. Most importantly, this potentially reduces the amount of hemodilution patients see from CPB initiation and therefore the lowest nadir hematocrit and consequently the amount of required homologous blood products needed during surgery.

Case of Hemolytic Disease of the Fetus and Newborn Treated Without Blood Products.

Hemolytic disease of the fetus and newborn (HDFN) affects 3/100,000 to 80/100,000 patients yearly and can cause severe anemia and hyperbilirubinemia. Recombinant human erythropoietin has been used as an adjunct therapy in patients with HDFN and hypo-regenerative anemia in the setting of receiving intrauterine blood transfusions. This case describes a patient with HDFN, in which the family were Jehovah Witnesses, and blood transfusions were declined. The patient had symptomatic anemia with a hematocrit nadir of 18.6%. The patient was successfully treated with recombinant human erythropoietin, ferrous sulfate, and folic acid, avoiding the need for transfusion.

Hyperlactatemia in patients undergoing pulmonary endarterectomy with deep hypothermic circulatory arrest: Risk factors and its effects on the outcome.

To determine the risk factors of hyperlactatemia in pulmonary endarterectomy (PEA) surgery and assess whether elevated blood lactate levels are associated with adverse outcomes. In this retrospective observational study, a total of 111 consecutive patients who underwent PEA for chronic thromboembolic pulmonary hypertension at the XXX Hospital between December 2016 and January 2022 were included. We retrospectively evaluated arterial blood samples analyzed intraoperatively. The pre- and intraoperative risk factors for hyperlactatemia and the postoperative outcomes were recorded. Lactate levels gradually increased during surgery. The optimal cut-off lactate level for major postoperative complications, calculated using receiver operating characteristic analysis, was 7.0mmol/L. Deep hypothermic circulatory arrest (DHCA) duration, nadir hematocrit, and preoperative pulmonary vascular resistance were risk factors for lactate levels >7mmol/L. Moreover, the intraoperative peak lactate level during PEA under DHCA was found to be a statistically significant predictor of major complications being associated with longer mechanical ventilation time (r = 0.294; p = .003) and intensive care unit length of stay (r = 0.327; p = .001). Deep hypothermic circulatory arrest duration, nadir hematocrit, and preoperative pulmonary vascular resistance were associated with hyperlactatemia. Increased lactate levels were independent predictors of longer mechanical ventilation time, intensive care unit length of stay, and major complications.

Abstract 12145: Intraoperative Anemia Mediates Sex Disparity in Operative Mortality After Coronary Artery Bypass Grafting

Introduction: Women undergoing coronary artery bypass grafting (CABG) have higher mortality compared with men, yet its drivers are unclear. Hypothesis: The association of female sex with the risk of operative mortality after CABG may be mediated by intraoperative anemia. Aim: To investigate the relationship between sex, intraoperative anemia, and operative mortality. Methods: Retrospective cohort study of 1,434,225 isolated primary CABG patients (344,357 women) from the Adult Cardiac Surgery Database of the Society of Thoracic Surgeons (2011-2022). The primary outcome was operative mortality. The attributable risk (AR, quantifying the risk-adjusted strength of the association of female sex with CABG outcomes) was calculated. Causal mediation analysis adjusted for 42 baseline risk factors was used to derive the total effect of female sex on mortality risk and the proportion of that effect mediated by intraoperative anemia (nadir hematocrit). Spline regression evaluated the relationship of operative mortality and nadir intraoperative hematocrit. Results: Women had lower median preoperative hematocrit (36.9%, interquartile range [IQR] 33.3-40.0 vs 41.0% [37.4-44.0], standardized mean difference [SMD] 74.0%) and nadir intraoperative hematocrit (22.0% [20.0-25.0] vs 27.0% [24.0-30.0], SMD 97.0%) compared with men. Women had higher operative mortality than men (2.8% vs 1.7%, p&lt;0.001, adjusted odds ratio 1.36, 95% confidence interval [CI] 1.30-1.41). The AR of female sex for operative mortality was 1.21 (95% CI 1.17-1.24). After adjusting for nadir intraoperative hematocrit, the AR was reduced by 43% (1.12, 95% CI 1.09-1.16). Intraoperative anemia mediated 38.5% of the increased mortality risk associated with female sex (95% CI 32.3-44.7%). Spline regression showed a stronger association between operative mortality and nadir intraoperative hematocrit at hematocrit values below 22.0% (p&lt;0.001). Conclusions: The association of female sex with increased CABG operative mortality is mediated to a large extent by intraoperative anemia. Avoiding nadir intraoperative hematocrit values below 22.0% may reduce sex differences in CABG operative mortality.

Risk factors of hyperlactatemia during pulmonary endarterectomy under deep hypothermic circulatory arrest and its influence on prognosis

Objective: To investigate the incidence, risk factors, and outcomes of hyperlactatemia after pulmonary endarterectomy (PEA) under deep hypothermic circulatory arrest (DHCA). Methods: From December 2016 to January 2022, patients receiving PEA in China-Japan Friendship Hospital were enrolled in the study. Arterial blood samples were analyzed intraoperatively. Multivariate logistic regression analysis was performed to identify the predictors of intraoperative lactate elevation as well as major factors influencing the clinical outcome of the surgery. Results: A total of 110 patients (69 males and 41 females) were enrolled, aged (50.6±12.8) years. Receiver operating characteristic curve yielded an optimal cut-off lactate level of 7 mmol/L for predicting major postoperative complications (re-operation, re-intubation, postoperative renal failure requiring renal replacement therapy, wound infection, stroke, atrial fibrillation, and perioperative extracorporeal membrane oxygenation usage within 48 hours after surgery). Thirty-nine patients (35.5%) had an intraoperative peak arterial lactate level of≥7 mmol/L. According to intraoperative peak arterial lactate level, the patients were divided into two groups (<7 mmol/L and≥7 mmol/L). There were no statistically significant differences in age, sex and body mass index between the two groups (all P>0.05). Intraoperative peak lactate level was associated with prolonged mechanical ventilation time (r=0.262, P=0.008) and intensive care unit length of stay (r=0.304, P=0.002). Multivariate logistic regression analysis identified three key variables associated with lactate level≥7 mmol/L: DHCA duration (OR=1.186, 95%CI: 1.027-1.370, P=0.020), nadir hematocrit (HCT) (OR=0.580, 95%CI: 0.341-0.988, P=0.045) and preoperative pulmonary vascular resistance (PVR) (OR=1.096, 95%CI: 1.020-1.177, P=0.012). Patients with lactate≥7 mmol/L carried a higher rate of major complications (P=0.001). For patients with lactate≥7 mmol/L, 41.0% (16 out of 39 cases) had major complications, while for patients with lactate<7 mmol/L, only 14.1% (10 out of 71) had major complications. There was no statistically significant difference in mortality (8.5% vs 10.3%, P=0.753) between patients with different lactate levels. Moreover, intraoperative peak lactate level was a predictor of postoperative combined morbidity (OR=1.625, 95%CI: 1.176-2.245, P=0.003). Conclusion: High intraoperative lactate levels are associated with higher preoperative PVR, lower nadir HCT, and longer DHCA duration. Intraoperative lactate levels are independently associated with increased combined morbidity.

Perioperative Anemia and Transfusions and Late Mortality in Coronary Artery Bypass Patients

BackgroundPerioperative anemia and transfusions are associated with adverse operative outcomes after coronary artery bypass graft surgery (CABG). Their individual association with long-term outcomes is unclear. MethodsPatients aged 65 years and older who had undergone CABG and were in The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (n = 504,596) from 2011 to 2018 were linked to Centers for Medicare and Medicaid Service data to assess long-term survival. The association of intraoperative anemia defined by intraoperative nadir hematocrit (nHct) and red blood cell (RBC) transfusions, and their interactions, on long-term mortality were assessed with Kaplan-Meier estimates and multivariable Cox regression. Restricted cubic splines were used to explore the association between nHct as a continuous variable and long-term mortality. Results258,398 on-pump CABG STS Adult Cardiac Surgery Database patients surviving the perioperative period were linked to Centers for Medicare and Medicaid Service claims files. Per World Health Organization criteria, 41% had preoperative anemia. Mean intraoperative nHct was 24%; RBC transfusion rate was 43.7%. Univariable analysis associated both RBC transfusion and lower nHct with worse survival. Lower nHct was only marginally associated with risk-adjusted mortality: adjusted hazard ratio (AHR) 1.04 (95% CI, 1.01-1.06) and 1.07 (95% CI, 1.00-1.14) at nHct 20% and at nHct 14%, respectively. RBC transfusion was associated with significantly higher adjusted mortality irrespective of timing of transfusion: AHR intraoperative 1.21 (95% CI, 1.18-1.27); AHR postoperative 1.26 (95% CI, 1.22-1.30); AHR both 1.46 (95% CI, 1.40-1.52) and across all levels of nHct. RBC transfusion was not associated with improved survival at any level of nHct. ConclusionsAmong Medicare CABG patients, RBC transfusions were associated with increased risk-adjusted late mortality across all levels of nHct whereas intraoperative anemia was only marginally so. Tolerance of lower intraoperative nHct than currently accepted may be preferable to transfusions.

Association Between Nadir Hematocrit and Severe Acute Kidney Injury After Off-Pump Coronary Artery Bypass Graft Surgery: A Retrospective Cohort Study Based on the MIMIC-IV Database

BACKGROUND We aimed to evaluate the association between postoperative nadir hematocrit (Hct) and severe acute kidney injury (AKI) in patients undergoing off-pump coronary artery bypass graft (OPCABG) surgery. MATERIAL AND METHODS Data of patients who received OPCABG were extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. A generalized additive model was applied to explore the relationship between nadir Hct and severe AKI. Patients were divided into 4 groups by quartiles of postoperative nadir Hct, with the lowest group (Hct <25%) as reference. We conducted multivariate logistic regression models to calculate adjusted odds ratios (OR) and 95% CI and evaluate trend among the 4 groups. RESULTS In total, 1783 OPCABG patients were included. A nonlinear association between nadir Hct and severe AKI was identified. After adjusting for potential confounders, nadir Hct was negatively associated with risk of severe AKI when Hct was less than 31%; there was no statistical significance between highest Hct group (Hct ≥31%) and control group (Hct <25%; P>0.05). Tests for trend were significant (P<0.05). Subgroup analyses showed each 1% increase in postoperative nadir Hct was associated with a 23% decrease in risk of severe AKI (OR, 0.77; P=0.002) in lower BMI group (<30 kg/m²). CONCLUSIONS The association between postoperative nadir Hct and severe AKI in patients after OPCABG was nonlinear. Lower nadir Hct may be associated with increased risk of severe AKI when Hct values are less than 31%. However, no statistical significance was found between the highest Hct group and control group.

Incidence and risk factors of acute kidney injury after maze operation in patients with rheumatic mitral valve disease.

BackgroundAcute kidney injury (AKI) is one of the most common complications after cardiac surgery. While current guidelines indicate that surgical ablation does not increase the risk of renal failure, recent studies have produced conflicting results. This study was conducted to evaluate the incidence of AKI after maze procedure in patients with rheumatic mitral valve disease and atrial fibrillation, and to elucidate risk factors associated with postoperative AKI.MethodsBetween 2011 and 2020, 203 patients with rheumatic mitral valve disease and atrial fibrillation (61.4±8.7 years, male:female =67:136) who underwent concomitant maze procedure and mitral valve replacement were retrospectively reviewed. Other combined procedures included aortic valve operations (n=64, 31.5%) and tricuspid valve procedures (n=149, 73.4%). The AKI was defined as an increase of serum creatinine level by 1.5 times after surgery based on the RIFLE (Risk, Injury, Failure, Loss, and End stage) criteria. A multivariable logistic regression analysis was performed to evaluate risk factors associated with postoperative AKI.ResultsPostoperative AKI developed in 76 patients (37.4%). The multivariable analysis demonstrated that age [odds ratio (OR), 95% confidence interval (CI): 1.065, 1.025–1.107; P=0.001], cardiopulmonary bypass (CPB) time (1.007, 1.002–1.013; P=0.009) and nadir hematocrit during CPB (0.854, 0.740–0.985; P=0.031) were associated with postoperative AKI.ConclusionsPostoperative AKI occurred in more than one thirds of patients with rheumatic mitral valve disease and atrial fibrillation who underwent combined mitral valve replacement and maze procedure. Optimization of CPB management might be needed to prevent postoperative AKI after maze procedure.

Effect of nadir hematocrit during cardiopulmonary bypass on the early outcomes after surgical repair of acute type A aortic dissection

Although hemodilution during hypothermic cardiopulmonary bypass (CPB) had been thought to improve microcirculation and reduce blood viscosity, there has been no report investigating the effect of low nadir hematocrit (Hct) values caused by severe hemodilution on the surgical outcomes of patients with acute type A aortic dissection (ATAAD). We retrospectively reviewed 112 consecutive patients who emergently underwent emergency surgical repair of ATAAD at our institution. The patients were classified into the high Hct (nadir Hct ≥ 21% during CPB; n = 51) and low Hct (nadir Hct < 21% during CPB; n = 61) groups. After propensity score matching of preoperative characteristics, surgical outcomes were compared between the groups. Although there was no difference in the surgical procedure, longer CPB time and more blood transfusion during surgery were needed in the low Hct group than in the high Hct group. After surgery, estimated glomerular filtration rate was significantly lower (p = .015), lactaic acid was higher (p = .045), and intubation time was longer (p = .018) in the low Hct group than in the high Hct group, although there was no difference in hospital mortality between the groups. The AUC of the nadir Hct during CPB as a prognostic indicator of prolonged postoperative ventilator support was 0.8, with the highest accuracy at 16.7% (sensitivity 88%, specificity 76.9%). In all cohorts, female sex was an independent risk factor for a lower nadir Hct value of <21% during CPB. A lower nadir Hct value of <21% during CPB may be associated with postoperative renal dysfunction and prolonged ventilator support in patients with ATAAD.

Intraoperative nadir hematocrit as a poor outcome predictor after acute type A aortic dissection surgey.

Acute type A aortic dissection is a life-threatening disease associated with high morbidity and mortality that requires urgent surgical intervention. Hemodilution is inevitable in cardiac operations performed with cardiopulmonary bypass, which leads to nadir hematocrit levels. Studies have shown that nadir hematocrit levels are associated with poor postoperative outcomes. The management strategy of intraoperative anemia in these operations is still controversial. Should we follow the patients with intraoperative low hematocrit values or should we transfuse them? In addition to intraoperative nadir hematocrit, cannulation strategies play an important role in early postoperative outcomes after aortic dissection surgery.

The Role of Race on Acute Kidney Injury After Cardiac Surgery

BackgroundAcute kidney injury (AKI) frequently complicates cardiac surgery and is more common among Black patients. We evaluated determinants of race-based differences in AKI rates. MethodsSerum creatinine-based criteria were used to identify adult cardiac surgical patients having postoperative AKI in the Perfusion Measures and Outcomes (PERForm) Registry (July 1, 2014, to June 30, 2019). Patient characteristics, operative details, and outcomes were compared by race (Black vs White) after excluding patients with preoperative dialysis, missing preoperative or postoperative creatinine, or other races. A mixed effects model (adjusting for demographics, comorbidities, surgical factors) used hospital as a random effect to predict postoperative stage 2 or 3 AKI. Propensity score analyses were conducted to evaluate robustness of the primary analyses. ResultsThe study cohort included 34 520 patients (8% Black). More Black patients than White patients were female (43% vs 27%, P < .001), and had hypertension (93% vs 87%, P < .001) and diabetes mellitus (51% vs 41%, P < .001). Acute kidney injury of stage 2 or greater occurred in 1697 patients (5%), more often among Black than White patients (8% vs 5%, P < .001). Intraoperatively, Black patients had lower nadir hematocrits (23 vs 26, P < .001), and were more likely to be given transfusions (22% vs 14%, P < .001). After adjustment, Black race (compared with White) independently predicted odds for postoperative AKI (adjusted odds ratio 1.50; 95% confidence interval, 1.26 to 1.78). The multivariable findings were similar in propensity score analyses. ConclusionsDespite accounting for differences in risk factors and intraoperative practices, Black patients had a 50% increased odds for having moderate-severe postoperative AKI compared with White patients. Additional evaluations are warranted to identify potential targets to address racial disparities in AKI outcomes.

Oxygen delivery-guided perfusion for the prevention of acute kidney injury: A randomized controlled trial

ObjectivesThe reduction of postoperative acute kidney injury in patients undergoing cardiopulmonary bypass surgery using an oxygen delivery-guided perfusion strategy (oxygen delivery strategy) for cardiopulmonary bypass management compared with a fixed flow perfusion (conventional strategy) remains controversial. The purpose of this study was to determine whether a oxygen delivery strategy would reduce the incidence of postoperative acute kidney injury in patients undergoing cardiopulmonary bypass surgery. MethodsWe randomly enrolled 300 patients undergoing cardiopulmonary bypass surgery. Patients were randomly assigned to a oxygen delivery strategy (maintaining a oxygen delivery index value >300 mL/min/m2 through pump flow adjustments during cardiopulmonary bypass) or a conventional strategy (a target pump flow was determined on the basis of the body surface area). The primary end point was the development of acute kidney injury. Secondary end points were the red blood cell transfusion rate and number of red blood cell units, intubation time, postoperative length of stay in the intensive care unit and the hospital, predischarge estimated glomerular filtration rate, and hospital mortality. ResultsAcute kidney injury occurred in 20 patients (14.6%) receiving the oxygen delivery strategy and in 42 patients (30.4%) receiving the conventional strategy (relative risk, 0.48; 95% confidence interval, 0.30-0.77; P = .002). The secondary end points were not significantly different between strategies. In a prespecified subgroup analysis of patients who had nadir hematocrit less than 23% or body surface area less than 1.40 m2, the oxygen delivery strategy seemed to be superior to the conventional strategy and the existence of quantitative interactions was suggested. ConclusionsAn oxygen delivery strategy for cardiopulmonary bypass management was superior to a conventional strategy with respect to preventing the development of acute kidney injury.

Quantification of Blood Loss Improves Detection of Postpartum Hemorrhage and Accuracy of Postpartum Hemorrhage Rates: A Retrospective Cohort Study.

ObjectiveTo evaluate the ability of estimated blood loss (EBL) and quantitative blood loss (QBL) to predict the need for blood transfusion in postpartum patients.MethodsThis is a retrospective observational study involving all deliveries one year before and after the change from EBL to QBL assessment in June 2017. Blood loss, need for blood transfusion, admission hematocrit, and postpartum nadir hematocrit were collected. Descriptive and bivariable analyses were performed. Receiver operator curves were compared.ResultsOverall, the baseline characteristics between the EBL (n=2743) and QBL (n=2,712) groups were similar. Although there was a higher rate of blood loss ≥ 1,000 mL in QBL vs EBL (6.5% vs 2.1%, P<0.001), there was no difference in the rate of blood transfusions (2.0% vs 2.0%, P=1). Among cesarean deliveries, QBL outperformed EBL for predicting blood transfusion and/or ≥10 point drop in hematocrit (AUC 0.75 vs 0.66, P=0.02). QBL also outperformed EBL for predicting transfusion after vaginal delivery (AUC 0.93 vs 0.81, P=0.03). ConclusionQBL is a more sensitive test for detecting clinically significant blood loss, which could lead to earlier recognition of hemorrhage and interventions.

Conventional Ultrafiltration During Elective Cardiac Surgery and Postoperative Acute Kidney Injury

Conventional ultrafiltration (CUF) during cardiopulmonary bypass (CPB) serves to hemoconcentrate blood volume to avoid allogeneic blood transfusions. Previous studies have determined CUF volumes as a continuous variable are associated with postoperative acute kidney injury (AKI) after cardiac surgery, but optimal weight-indexed volumes that predict AKI have not been described. Retrospective cohort. Single-center university hospital. A total of 1,641 consecutive patients who underwent elective cardiac surgery between June 2013 and December 2015. The CUF volume was removed during CPB in all participants as part of routine practice. The authors investigated the association of dichotomized weight-indexed CUF volume removal with postoperative AKI development to provide pragmatic guidance for clinical practice at the authors' institution. Primary outcomes of postoperative AKI were defined by the Kidney Disease: Improving Global Outcomes staging criteria and dichotomized, weight-indexed CUF volumes (mL/kg) were defined by (1) extreme quartiles (<Q1 v >Q3) and (2) Youden's criterion that best predicted AKI development. Multivariate logistic regression models were developed to test the association of these dichotomized indices with AKI status. Postoperative AKI occurred in 827 patients (50.4%). Higher CUF volumes were associated with AKI development by quartiles (CUF >Q3 = 32.6 v CUF < Q1 = 10.4 mL/kg; odds ratio [OR] = 1.68, 95% CI: 1.19-2.3) and Youden's criterion (CUF ≥ 32.9 v CUF <32.9 mL/kg; OR = 1.60, 95% CI: 1.21-2.13). Despite similar intraoperative nadir hematocrits among groups (p = 0.8), higher CUF volumes were associated with more allogeneic blood transfusions (p = 0.002) and longer lengths of stay (p < 0.001). Removal of weight-indexed CUF volumes > 32 mL/kg increased the risk for postoperative AKI development. Importantly, CUF volume removal of any amount did not mitigate allogeneic blood transfusion during elective cardiac surgery. Prospective studies are needed to validate these findings.

Pre-Operative Risk Factors of Transfusion during Myomectomy

Study Objective Identify pre-operative risk factors for transfusion during abdominal myomectomy. Design Retrospective cohort study. Setting Academic Medical Center. Patients or Participants Patients undergoing abdominal myomectomy by a single surgeon between 2010 and 2016. Interventions Pre-operative patient characteristic data, intra-operative data, and peri-operative transfusion and blood loss data were collected retrospectively. Prior Pelvic Surgery was defined as myomectomy, cesarean section, and/or endometriosis surgery; Transfusion was defined as intra-operative cell salvage transfusion, intra-operative allogeneic transfusion, and/or post-operative allogeneic transfusion. Composite Blood Loss Morbidity was defined as presence of any transfusion, reoperation after myomectomy, hematocrit nadir ≤21, and/or estimated blood loss (EBL) ≥1000mL. Logistic regression analysis of risk factors for transfusion was performed. Measurements and Main Results 554 patient charts were available for review. Eighty (14.4%) patients underwent transfusion as a result of myomectomy (66 (12%) intra-operative cell salvage, 2 (0.4%) intra-operative allogeneic, and 30 (5.4%) post-operative allogeneic). Women with prior pelvic surgery (OR 3.1), prior myomectomy (OR 2.6), prior endometriosis surgery (OR 5.1), prior UAE (OR 6.3), large uterine size ≥20 weeks (OR 4.8), large fibroid (≥10cm) on MRI (OR 2.1), low preoperative hematocrit 2.3 hours (OR 9.7), or many (≥50) fibroids removed (OR 2.1) had significantly greater odds of having a transfusion (P Conclusion Knowledge of patient risk factors for transfusion as a result of abdominal myomectomy is crucial for patient counseling and peri-operative planning.

Introduction of a Novel System for Quantitating Blood Loss After Vaginal Delivery: A Retrospective Interrupted Time Series Analysis With Concurrent Control Group

Postpartum hemorrhage (PPH) is a leading cause of maternal mortality worldwide. While volumetric and gravimetric blood loss measurement techniques have been shown to increase PPH detection compared to visual estimation of blood loss (vBL), a combination of these methods has not been evaluated. The primary aim of this study was to compare the change in odds of PPH detection after vaginal delivery (VD; the intervention series) versus cesarean delivery (CD; the control series) before versus after implementation of a device (Triton L&D, Gauss Surgical, Inc, Los Altos, CA) that combines gravimetric and volumetric estimation of blood loss (tBL). After institutional review board (IRB) approval, patients were identified who had a VD or CD at our institution 3 months before and 3 months after the implementation of a tBL device for VD. The levels and trends in odds of PPH detection (the primary outcome, defined as blood loss ≥500 mL for VD and ≥1000 mL for CD) were compared within and between delivery methods before and after implementation of the device. Secondary outcomes were blood loss ≥1000 mL, total blood loss, secondary uterotonic use, and a composite outcome related to PPH management (transfusion, vasopressor administration, and/or surgical procedures). A post hoc subgroup analysis compared nadir hematocrit, hematocrit reduction ≥10%, and difference between vBL or tBL and calculated blood loss (cBL) between VDs before and after introduction of the device. All outcome comparisons were performed using segmented regression with inverse probability of treatment weighting. The weighted odds ratio (wOR) of PPH detection post- versus preimplementation of the device was 2.74 (95% confidence interval [CI], 1.39-5.41; P = .004) for VDs versus 1.43 (95% CI, 0.72-2.85; P = .304) for CDs (P for interaction .190). No difference was detected in the secondary outcomes for VDs between time periods. In the subgroup of VD patients who had postdelivery hematocrits measured, the mean difference between vBL or tBL and cBL was smaller in the tBL (mean ± standard deviation [SD]: -237 ± 522 mL) versus vBL group (-600 ± 596 mL; weighted difference in means [95% CI]: 349 mL [13-684]; P = .042). In this interrupted time series analysis, the odds of PPH detection after VD increased after implementation of the tBL device. However, a statistical difference was not detected between the increase in PPH detection post- versus preimplementation of the device in VDs versus CDs.

Pediatric Blunt Renal Trauma. A Single Institution’s 20 Years Experience with Surgically Treated Patients.

Background: Kidney is the most common site of genitourinary trauma. 50% of all urinary injuries is kidney.Kidney is also affected in 8-12% of all blunt and penetrating trauma to abdomen. 80-90% of renal injury is caused by blunt injury GY. Children, compared to adults, have at a higher risk of renal injury from blunt trauma due to a variety of anatomic factors including decreased perirenal fat, weaker abdominal muscles, and a less ossified thoracic cage. While there are strong trends toward non-operative management of blunt renal trauma, there are no explicit guidelines for high grade injuries. Organ preservation in children is always a primary goal with solid organ injury.&#x0D; Aim of the work: The aim of the retrospective study is to show the specificity of kidney injury in children as well as the specificity of surgical treatment.&#x0D; Material and Methods: All 19 patients under the age of 18 who were admitted to Clinic for Pediatic surgery in Sarajevo with a diagnosis of renal trauma were retrospectively reviewed .The Echo an CT were used to identify patients with a renal injury. The time period examined was between January 1, 1999- 2019. Inclusion criteria were either a diagnosis of renal trauma or a diagnosis of blunt abdominal trauma and hematuria. Exclusion criterion was death due to an additional traumatic injury. The mechanism of injury (fall, car accident , assault) injury grade (I-V), the presence of hematuria, and demographic data to include age, weight, and sex, were recorded and reviewed. In addition, amount of blood product required, hematocrit nadir prior to transfusion to assist in ascertaining whether transfusion was necessary, surgical interventions performed, and hospital length of stay were also retrospectively analyzed. Due to the low sample size we used descriptive as opposed to inferential statistics in our analysis.&#x0D; Result: Demographics include male to female ratio of 13:6 and the average age of patients was 11.9 + 4.6 years. Of the nineteen patients who underwent review, eleven (57,89%) children presented with a grade III renal injury, five with a grade IV injury and three with grade V injury. Six patients presented with gross hematuria and 3 with microscopic hematuria. Only four patients (22%) required blood transfusions, with the average hematocrit nadir being 31 + 5.3% (24.8-37.8). One of the two patients transfused had a concomitant grade IV splenic laceration with a hematocrit nadir of 24.8% and clinical symptoms consistent with shock.&#x0D; Conclusions:The specificity of the child's anatomy is an aggravating prognostic factor (the kidney is larger in relation to the body cavity than in adults, less protected against the ribs, the muscles of the body and the lower abdomen, the less developed peritoneal and retroperitoneal fatty tissue).It is recommended to initiate conservative treatment (leaching, infusion solution, monitoring) and possibly delayed surgical treatment.Indications for early surgicaly treatment are reserved only for patients with bleeding (absolute) and extravasation (relative).If it is necessary surgical treatment sould be maximally preserve kidney tissue.

Predictive factors for prolonged operative time in head and neck patients undergoing free flap reconstruction.

Defining the predictive factors associated with prolonged operative time may reduce post-operative complications, improve patient outcomes, and decrease cost of care. The aims of this study are to 1) analyze risk factors associated with prolonged operative time in head and neck free flap patients and 2) determine the impact of lengthier operative time on surgical outcomes. This retrospective cohort study evaluated 282 head and neck free flap reconstruction patients between 2011 and 2013 at a tertiary care center. Perioperative factors investigated by multivariate analyses included gender, age, American Society of Anesthesiologists class, tumor subsite, stage, flap type, preoperative comorbidities, and perioperative hematocrit nadir. Association was explored between operative times and complications including flap take back, flap survival, transfusion requirement, flap site hematoma, and surgical site infection. Mean operative time was 418.2±88.4 (185-670) minutes. Multivariate analyses identified that ASA class III (beta coefficient+24.5, p=.043), stage IV tumors (+34.8, p=.013), fibular free flaps (-44.8, p=.033 for RFFF vs. FFF and-67.7, p=.023 for ALT vs FFF) and COPD (+36.0, p=.041) were associated with prolonged operative time. History of CAD (-43.5, p=.010) was associated with shorter operative time. There was no statistically significant association between longer operative time and adverse flap outcomes or complications. As expected, patients who were medically complex, had advanced cancer, or underwent complex flap reconstruction had longer operative times. Surgical planning should pay special attention to certain co-morbidities such as COPD, and explore innovative ways to minimize operative time. Future research is needed to evaluate how these factors can help guide planning algorithms for head and neck patients.