Prediction of Hidden Blood Loss During Posterior Spinal Surgery

Objective Identification of the risk factors for extraordinary hidden blood loss(HBL) could clarify the underlying causes and provide more appropriate management. This study aims to identify the predictors of HBL in spinal surgery.Methods Medical records were retrospectively retrieved to collect the data of patients who undergoing posterior thoracic and lumbar fusion surgery or scoliosis surgery. Demographic information, perioperative visible blood loss volume, as well as laboratory results were recorded. The patients receiving fusion surgery or scoliosis surgery were further divided into the HBL positive subgroup and the HBL negative subgroup. Differences in the variables between the groups were then analyzed. Binary logistic regression analysis was performed to determine independent risk factors associated with HBL.Results For patients undergoing posterior spinal surgery, the independent risk factors associated with HBL were autologous transfusion(for fusion surgery P = 0.011, OR: 2.627, 95%CI: 1.574-2.782; for scoliosis surgery P < 0.001, OR: 2.268, 95%CI: 2.143-2.504) and allogeneic transfusion(for fusion surgery P < 0.001, OR: 6.487, 95%CI: 2.349-17.915; for scoliosis surgery P < 0.001, OR: 3.636, 95%CI: 2.389-5.231).Conclusion Intraoperative blood transfusion might be an early-warning indicator for perioperative HBL.

Efficacy of topical vs intravenous tranexamic acid in reducing blood loss and promoting wound healing in bone surgery:A systematic review and meta-analysis

BACKGROUND Tranexamic acid(TXA)has been used as an anti-fibrinolytic drug for over half a century and has received much attention in recent decades.AIM To evaluate the efficacy of topical vs intravenous TXA in reducing blood loss and promoting wound healing in bone surgery.METHODS From the electronic resources,PubMed,Cochrane Library,Embase,ISI,and Scopus were used to perform a literature search over the last 10 years between 2010 and 2020.EndNote™X8 was used for managing the electronic resource.Searches were performed with mesh terms.The data were retracted blindly by two independent reviewers.Random effects were used to deal with potential heterogeneity and I2 showed heterogeneity.Chi-square(I2)tests were used to quantify the extent of heterogeneity(P<0.01 was considered statistically significant).The efficacy of topical TXA in reducing blood loss and promoting wound healing in bone surgery was compared with intravenous TXA and placebo.RESULTS According to the research design,1360 potentially important research abstracts and titles were discovered in our electronic searches,and 18 papers remained in agreement with our inclusion criteria.It was found that TXA reduced 277.51 mL of blood loss compared to placebo,and there was no significant difference between topical TXA and IV TXA in reducing blood loss in bone surgery.Our analyses also showed that TXA significantly reduced blood transfusion compared to placebo and there was no significant difference between topical TXA and IV TXA.CONCLUSION The use of both topical and intravenous TXA are equally effective in reducing blood loss in bone surgery,which might be beneficial for wound healing after surgery.

Evaluating the Efficacy of Remifentanil-Propofol versus Isoflurane in Reducing Blood Loss with Considering Depth of Anesthesia during Endoscopic Sinus Surgery

Several methods have been suggested to decrease bleeding during surgery, one of which is the usage of hypotensive anesthetic agents. Endoscopic Sinus Surgery (ESS) is one of the surgeries which need a clear field and the amount of bleeding profoundly impacts the ability of surgeons. Current study was designed to evaluate the effect of remifentanil combined with propofol versus Isoflurane on blood loss during ESS and its possible interaction with Depth of Anesthesia. Fifty one patients comprising 15 females and 36 males undergoing ESS were chosen for this study. One group received propofol and remifentanil to induce and maintain anesthesia and the second group received Isoflurane. Mean Arterial Blood Pressure (MAP), Depth of Anesthesia and total blood loss were recorded for the patients of both group. Data were analyzed using t-test, Repeated Measures ANOVA and Pearson’s correlation. P 0.05 was considered statistically significant. Both agents induced hypotension during surgery. No significant difference was observed in total blood loss between two groups. DA was decreased in both groups, but no significant correlation was found between DA and MAP or DA and blood loss. There is no significant difference between remifentanil combined with propofol and Isoflurane in decreasing blood loss during ESS, thus we suggest usage of hypotensive anesthetic agent regardless of its type is ESS.

Hemoglobin loss method calculates blood loss during pancreaticoduodenectomy and predicts bleeding-related risk factors

BACKGROUND The common clinical method to evaluate blood loss during pancreaticoduoden-ectomy(PD)is visual inspection,but most scholars believe that this method is extremely subjective and inaccurate.Currently,there is no accurate,objective me-thod to evaluate the amount of blood loss in PD patients.We retrospectively analyzed the clinical data of 341 patients who underwent PD in Shandong Provincial Hospital from March 2017 to February 2019.According to different surgical methods,they were divided into an open PD(OPD)group and a laparoscopic PD(LPD)group.The differences and correlations between the in-traoperative estimation of blood loss(IEBL)obtained by visual inspection and the intraoperative calculation of blood loss(ICBL)obtained using the Hb loss method were analyzed.ICBL,IEBL and perioperative calculation of blood loss(PCBL)were compared between the two groups,and single-factor regression analysis was performed.RESULTS There was no statistically significant difference in the preoperative general patient information between the two groups(P>0.05).PD had an ICBL of 743.2(393.0,1173.1)mL and an IEBL of 100.0(50.0,300.0)mL(P<0.001).There was also a certain correlation between the two(r=0.312,P<0.001).Single-factor analysis of ICBL showed that a history of diabetes[95%confidence interval(CI):53.82-549.62;P=0.017]was an independent risk factor for ICBL.In addition,the single-factor analysis of PCBL showed that body mass index(BMI)(95%CI:0.62-76.75;P=0.046)and preoperative total bilirubin>200μmol/L(95%CI:7.09-644.26;P=0.045)were independent risk factors for PCBL.The ICBLs of the LPD group and OPD group were 767.7(435.4,1249.0)mL and 663.8(347.7,1138.2)mL,respectively(P>0.05).The IEBL of the LPD group 200.0(50.0,200.0)mL was slightly greater than that of the OPD group 100.0(50.0,300.0)mL(P>0.05).PCBL was greater in the LPD group than the OPD group[1061.6(612.3,1632.3)mL vs 806.1(375.9,1347.6)mL](P<0.05).CONCLUSION The ICBL in patients who underwent PD was greater than the IEBL,but there is a certain correlation between the two.The Hb loss method can be used to evaluate intraoperative blood loss.A history of diabetes,preoperative bilirubin>200μmol/L and high BMI increase the patient's risk of bleeding.

Clinical significance of peripheral blood immune cells in patients with gastric cancer after surgery

BACKGROUND Gastric cancer is one of the most common malignant tumors worldwide,and surgical resection is one of the main ways to treat gastric cancer.However,the immune status of postoperative patients is crucial for prognosis and survival,and immune cells play an important role in this process.Therefore,it is helpful to understand the immune status of postoperative patients by evaluating the levels of peripheral blood immune cells,especially total T cells(CD3+),helper T cells(CD3+CD4+),and suppressor T cells(CD3+CD8+),and its relationship to sur-vival.AIM To analyzed the immune cells in peripheral blood of patients with gastric cancer after surgery,detect the levels of total T cells,helper T cells and suppressor T cells.METHODS A total of 58 patients with gastric cancer who received surgical treatment were included in the retrospective study.Flow cytometry was used to detect the level of peripheral blood immune cells and analyze the correlation between total T cells,helper T cells and inhibitory T cells.To explore the relationship between these immune markers and patient survival.RESULTS The results showed that the levels of total T cells,helper T cells,and suppressor T cells changed in patients after gastric cancer surgery.There was a significant positive correlation between total T cells,helper T cells and suppressor T cells(r=0.35,P<0.01;r=0.56,P<0.01).However,there was a negative correlation between helper T cells and suppressor T cells(r=-0.63,P<0.01).Follow-up showed that the survival rate of patients in the high-level total T cell group was significantly higher than that in the low-level group(28.87±24.98 months vs 18.42±16.21 months).The survival curve shows that the curve of patients in the high-level group is shifted to the upper right,and that of the low-level group is shifted downward.There was no significant difference between the levels of helper T cells and suppressor T cells and patient survival time.CONCLUSION By detecting peripheral blood immune cells with flow cytometry,we can initially evaluate the immune status of patients after gastric cancer surgery and initially explore its relationship with patient survival.

Intraoperative Blood Glucose Levels and Postoperative Acute Kidney Injury in Pediatric Patients Having Congenital Heart Surgery under Cardiopulmonary Bypass

Purpose:This study sought to explore the effect of intraoperative mean blood glucose levels and variability on postoperative acute kidney injury(AKI)in children undergoing congenital cardiac surgery.Methods:We conducted a prospective nested case-control study in children(age<18 years)undergoing congenital heart surgery with cardiopulmonary bypass(CPB)at the Fuwai Hospital between April 01,2022 and July 30,2022.Cases were individuals who developed AKI within the first postoperative 7 days(AKI group)and controls were those without AKI(Non-AKI group)according to KDIGO criteria.AKI and Non-AKI groups unmatched and 1:1 matched by age,sex,and baseline serum creatinine were separately analyzed.Multivariate logistic and conditional logistic regressions were used to assess the associations between blood glucose variables and AKI.Results:688 consecutively approached patients were included in the final analysis.On multivariate analysis,intra-CPB(adjusted odds ratio[OR]0.802;95%confidence interval[CI],0.706 to 0.912;p=0.001)and post-CPB(adjusted OR 0.830;95%CI,0.744 to 0.925;p=0.001)blood glucose levels were associated with postoperative AKI.There were no significant differences in pre-CPB blood glucose(adjusted OR 0.926;95%CI,0.759 to 1.129;p=0.446)or intraoperative glycemic fluctuations(adjusted OR 0.905;95%CI,0.723 to 1.132;p=0.382)between AKI and Non-AKI groups.Results based on matched cases and controls were consistent with those from the unmatched analyses.Conclusion:Higher intraoperative blood glucose levels during and after CPB were protective factors against postoperative AKI in pediatric patients after congenital heart surgery.

Wearable Smart Sensor System for Medical Monitoring with an Assessment of the Level of Blood Loss and Pain Shock Because of Trauma or Injury

Blood loss in peacetime is mainly due to the normal menstrual cycle in women or diseases with surgical intervention. In wartime, blood loss in military personnel is a characteristic sign of a closed or open injury of the body during internal or external bleeding. Access to clinical care for wounded military personnel injured on the battlefield is limited and has long delays compared to patients in peacetime. Most of the deaths of wounded military personnel on the battlefield occur within the first hour after being wounded. The most common causes are delay in providing medical care, loss of time for diagnosis, delay in stabilization of pain shock and large blood loss. Some help in overcoming these problems is provided by the data in the individual capsule, which each soldier of the modern army possesses;however, data in an individual capsule is not sufficient to provide emergency medical care in field and hospital conditions. This paper considers a project for development of a smart real-time monitoring wearable system for blood loss and level of shock stress in wounded persons on the battlefield, which provides medical staff in field and hospital conditions with the necessary information to give timely medical care. Although the hospital will require additional information, the basic information about the victims will already be known before he enters the hospital. It is important to emphasize that the key term in this approach is monitoring. It is tracking, and not a one-time measurement of indicators, that is crucial in a valid definition of bleeding.

Effect of Intravenous Tranexamic Acid in Reducing Blood Loss during and after Elective Caesarean Section in a Third Level Health Institution: A Randomized Controlled Study

Background: Blood loss during caesarean section (C/S) may lead to postpartum haemorrhage, and is one of the direct causes of maternal mortality and morbidity globally. Tranexamic acid is recommended in the treatment of postpartum haemorrhage (PPH) if oxytocin and other utertonics are ineffective in controlling PPH. In this centre it is not used prophylactically to reduce blood during caesarean section. Aim: To assess the effect of prophylactic intravenous tranexamic acid on blood loss during and after elective C/S at the University of Port Harcourt Teaching Hospital (UPTH). Methods: This was a prospective, single-blind, randomized, placebo-controlled interventional study conducted at the Obstetric theatre of UPTH from July 2020 to March 2021. Eligible women were randomized into two groups;seventy-two women received intravenous tranexamic acid while seventy-one women received a placebo. Socio-demographic data and the result of the study were collected through a proforma. Data collected was analyzed using Statistical Package for Social Sciences (SPSS) Version 22.0. The results were expressed in tables and charts as frequencies, percentages and mean. Chi-square test, Fisher’s exact, and T-test were used to determine the relationship between variables. P-value ≤ 0.05 was considered statistically significant. Results: The findings showed that tranexamic acid significantly reduced mean blood loss during and after C/S (p-value post-surgery was significantly lower in the tranexamic acid group (624.88 ± 200.76 ml) in comparison to the placebo group (864.24 ± 229.09 ml), p-value = 0.001. The mean post-C/S packed cell volume (PCV) was significantly higher among the tranexamic acid group (30.68% ± 2.80%) in comparison to the placebo group (28.07% ± 3.27%), t = 5.131, p-value = 0.0001. The maternal side effects were nausea and vomiting, 9 (12.5%) and 1 (1.4%) participants respectively. Conclusion: Tranexamic acid significantly reduced blood loss during and after elective C/S. Maternal side effects were less with tranexamic acid use.

The Correlation of Indices in r-TEG with Intra-operative Blood Loss in Neurosurgical Patients

Objective Intra-operative coagulopathy has a close relationship with blood loss and the prognosis of patients. Rapid-thrombelastography （r-TEG） is a comprehensive assessment of coagulation abnormalities and also an effective way for constructing blood transfusion. This study attempts to investigate the correlation of r-TEG indices with intra-operative hemorrhage. Methods Patients who underwent transphenoidal hypophysectomy and craniotomy from January 15 to April 30, 2013 in Peking Union Medical College hospital were recruited. All patients had pre- and post-operative r-TEG and conventional coagulation tests （CCTs）. Patients’ information and intra-operative blood loss as a percentage of estimated blood volume were recorded. Spearman’s correlation analyses were used for discovering the relationship between indices in r-TEG or CCTs and the intra-operative blood loss. The significant correlated index of r-TEG was further investigated using linear regression analysis. Results A total of 181 patients participated in this study. Intra-operative change of α-angle, which reflects the fibrinogen level and function, was the only r-TEG index that correlated with blood loss significantly （P=0.013, r= ？0.184）, thus challenging the current empirical cognition of the effects of intra-operative hemorrhage on coagulation. As intra-operative blood loss increased, α-angle decreased, and every 1% loss of estimated blood volume （EBV） led to 0.60 degree decrease of α-angle. As for CCT results, changes of fibrinogen and platelet count were also significantly correlated with blood loss （P=0.015 and P=0.001, respectively）.Conclusions Peri-operative change of α-angle, as an index of r-TEG, exhibited a significant negative correlation with intra-operative blood loss. The impact of hemorrhage on fibrinogen, instead of clotting factors, should be scrutinized.

Blood glucose management in the patient undergoing cardiac surgery: A review

Both diabetes mellitus and hyperglycemia per se are associated with negative outcomes after cardiac surgery. In this article, we review these associations, the possible mechanisms that lead to adverse outcomes, and the epidemiology of diabetes focusing on those patients requiring cardiac surgery. We also examine outpatient and perioperative management of diabetes with the same focus. Finally, we discuss our own efforts to improve glycemic management of patients undergoing cardiac surgery at our institution, including keys to success, results of implementation, and patient safety concerns.

Quantifying Maternal Blood Loss from the Hysterotomy at Cesarean Delivery

Background: With newer protocols, such as delayed cord clamping, becoming routine practice, determining the potential maternal consequences is important. In particular, establishing normative values for blood loss from the hysterotomy would be helpful in addressing techniques to minimize total blood loss for cesarean deliveries. Objective: Blood loss from the hysterotomy during cesarean delivery has not been reported using quantitative methods. We aimed to quantify the rate of blood loss during cesarean delivery from the hysterotomy between creation and closure. Methods: This single center, prospective, case series was collected in 2018. Women with singleton pregnancies undergoing cesarean delivery at ≥37 0/7 weeks at Brigham and Women’s Hospital were included. Delayed cord clamping was performed which allowed for quantification of blood loss through gravimetric methods and descriptive statistics were performed. Results: Twenty patients were included. The mean hysterotomy closure delay for cord blood collection was 47 seconds (SD 10.2) and the mean maternal blood volume collected was 110.8 mL (SD 53.4 mL). Blood loss per minute was calculated with a median of 150 mL/minute (IQR 88.8 mL, 95% CI 109.2 - 190.4 mL). The mean post-operative hematocrit drop was 4.4%, and there were no blood transfusions. There was a single hysterotomy extension and a quantified blood loss of 413 mL per minute. Conclusion: We found a mean blood loss of 150 mL/min without hysterotomy extension. With a hysterotomy extension, the blood lost per minute was more profound. This normative data can be helpful for surgical planning with regards to delayed cord clamping or cord blood collection for banking.

Blood pressure change during phacoemulsification and femtosecond laser-assisted cataract surgery

AIM： To evaluate blood pressure（BP） changes during phacoemulsification（PC） and femtosecond laser（FSL）-assisted cataract surgery.METHODS： A retrospective chart review was performed for all patients who received traditional phacoemulsification surgery（PC group） and FSL-assisted cataract surgery（FS group） from July 2013 to December 2014. Totally 206 eyes from 133 patients receiving the two types of procedures were included.Patient characteristics（age, gender, and hypertension history）, pre- and post-operative BPs were collected.RESULTS： The pro-operative systolic and diastolic BPs（mm Hg） were 124.89 ±20.48 vs 126.98 ±16.85, and71.88 ±9.81 vs 73.56 ±10.03, in PC and FS groups,respectively. While the post-operative systolic and diastolic BPs（mm Hg） were 130.13 ±22.59 vs 134.77 ±17.52, and 73.41 ±11.62 vs 78.89 ±12.2, in PC and FS groups, respectively. Paired-sample t-tests showed obvious systolic and diastolic BP elevations in FS group after surgery（P =0.001 and 0.007） and no reliability in PC group（P =0.094 and 0.359）. A linear regression model revealed systolic and diastolic BP elevations,which were related to longer surgical times for FS group（P =0.008 and 0.021）. Age, gender, and hypertension history were not correlated with blood pressure elevation in either group.CONCLUSION： BP increases but at a limited level after FSL-assisted cataract surgery compared to traditional phacoemulsification

Incidence and risk factors for vitreous loss in residents performing manual small-incision cataract surgery

AIM: To assess the incidence of vitreous loss and associated risk factors in residents performing manual small-incision cataract surgery(MSICS). METHODS: The present retrospective record review study was performed on 490 patients who underwent MSICS performed between November 2018 and December 2019 by 7 third-year postgraduate residents. The study group comprised of patients having intraoperative vitreous prolapse. All the surgeries were performed under supervision of a trained assistant. RESULTS: The mean age of the participants at the time of surgery was 68.42±2.05 y. Of the 490 patients, 250 patients were male, and 240 patients were female(P=0.23). A total of 215(43.9%) eyes had mature white cataract, 185(37.8%) eyes had brown cataract, and 90(18.3%) eyes had immature senile cataract. The incidence of intraoperative vitreous loss among residents was 2%(10/490). Vitreous loss occurred during hydrodissection [1/10(10%)], nucleus delivery [3/10(30%)], irrigation and aspiration [5/10(50%)], and intraocular lens insertion [1/10(10%)]. Multivariate stepwise Logistic regression analysis confirmed immature senile cataract [odds ratio(OR)=3.99;P=0.02], irrigation and aspiration of cortical material(OR=3.07;P=0.03), and anterior capsular extension(OR=3.22, P=0.03) as independent risk factors for vitreous loss. CONCLUSION: Immature senile cataract, irrigation and aspiration of cortical material, and anterior capsular extension are independent risk factors for vitreous loss. Our findings may serve as a guide for future trainers or residents learning MSICS.

Effect of Desmopressin on Platelet Aggregation and Blood Loss in Patients Undergoing Valvular Heart Surgery

Background：Blood loss after cardiac surgery can be caused by impaired platelet （PLT） function after cardiopulmonary bypass.Desmopressin or 1-deamino-8-D-arginine vasopressin （DDAVP） is a synthetic analog of vasopressin.DDAVP can increase the level of von Willebrand factor and coagulation factor Ⅷ,thus it may enhance PLT function and improve coagulation.In this study,we assessed the effects of DDAVP on PLT aggregation and blood loss in patients undergoing cardiac surgery.Methods：A total of 102 patients undergoing valvular heart surgery （from October 2010 to June 2011） were divided into DDAVP group （n =52） and control group （n =50）.A dose of DDAVP （0.3 μtg/kg） was administered to the patients intravenously when they were being rewarmed.At the same time,an equal volume of saline was given to the patients in the control group.PLT aggregation rate was measured with the AggRAM four-way PLT aggregation measurement instrument.The blood loss and transfusion,hemoglobin levels,PLT counts,and urine outputs at different time were recorded and compared.Results：The postoperative blood loss in the first 6 h was significantly reduced in DDAVP group （202 ± 119 ml vs.258 ± 143 ml,P =0.023）.The incidence of fresh frozen plasma （FFP） transfusion was decreased postoperatively in DDAVP group （3.8% vs.12%,P =0.015）.There was no significant difference in the PLT aggregation,urine volumes,red blood cell transfusions and blood loss after 24 h between two groups.Conclusions：A single dose of DDAVP can reduce the first 6 h blood loss and FFP transfusion postoperatively in patients undergoing valvular heart surgery,but has no effect on PLT aggregation.

Controlled low central venous pressure reduces blood loss and transfusion requirements in hepatectomy

AIM: To evaluate the effect of low central venous pressure (LCVP) on blood loss and blood transfusion in patients undergoing hepatectomy.

Low central venous pressure reduces blood loss in hepatectomy

AIM： To investigate the effect of low central venous pressure （LCVP） on blood loss during hepatectomy for hepatocellular carcinoma （HCC）. METHODS： By the method of sealed envelope, 50 HCC patients were randomized into LCVP group （n=25） and control group （n=25）. In LCVP group, CVP was maintained at 2-4 mmHg and systolic blood pressure （SBP） above 90 mmHg by manipulation of the patient＇s posture and administration of drugs during hepatectomy, while in control group hepatectomy was performed routinely without lowering CVP. The patients＇ preoperative conditions, volume of blood loss during hepatectomy, volume of blood transfusion, length of hospital stay, changes in hepatic and renal functions were compared between the two groups. RESULTS： There were no significant differences in patients＇ preoperative conditions, maximal tumor dimension, pattern of hepatectomy, duration of vascular occlusion, operation time, weight of resected liver tissues, incidence of post-operative complications, hepatic and renal functions between the two groups. LCVP group had a markedly lower volume of total intraoperative blood loss and blood loss during hepatectomy than the control group, being 903.9 ± 180.8 mL vs 2 329.4 ±2 538.4 （W=495.5, P〈0.01） and 672.4±429.9 mL vs 1 662.6±1 932.1 （W=543.5, P〈0.01）. There were no remarkable differences in the pre-resection and post-resection blood losses between the two groups. The length of hospital stay was significantly shortened in LCVP group as compared with the control group, being 16.3±6.8 d vs 21.5 ± 8.6 d （W= 532.5, P〈0.05）.CONCLUSION： LCVP is easily achievable in technique. Maintenance of CVP ≤4 mmHg can help reduce blood loss during hepatectomy, shorten the length of hospital stay, and has no detrimental effects on hepatic or renal function.

Blood loss,predictors of bleeding,transfusion practice and strategies of blood cell salvaging during liver transplantation

Blood loss during liver transplantation (OLTx) is a common consequence of pre-existing abnormalities of the hemostatic system,portal hypertension with multiple collateral vessels,portal vein thrombosis,previous abdominal surgery,splenomegaly,and poor "functional" recovery of the new liver.The intrinsic coagulopathic features of end stage cirrhosis along with surgical technical difficulties make transfusion-free liver transplantation a major challenge,and,despite the improvements in understanding of intraoperative coagulation profiles and strategies to control blood loss,the requirements for blood or blood products remains high.The impact of blood transfusion has been shown to be significant and independent of other well-known predictors of posttransplant-outcome.Negative effects on immunomodulation and an increased risk of postoperative complications and mortality have been repeatedly demonstrated.Isovolemic hemodilution,the extensive utilization of thromboelastogram and the use of autotransfusion devices are among the commonly adopted procedures to limit the amount of blood transfusion.The use of intraoperative blood salvage and autologous blood transfusion should still be considered an important method to reduce the need for allogenic blood and the associated complications.In this article we report on the common preoperative and intraoperative factors contributing to blood loss,intraoperative transfusion practices,anesthesiologic and surgical strategies to prevent blood loss,and on intraoperative blood salvaging techniques and autologous blood transfusion.Even though the advances in surgical technique and anesthetic management,as well as a better understanding of the risk factors,have resulted in a steady decrease in intraoperative bleeding,most patients still bleed extensively.Blood transfusion therapy is still a critical feature during OLTx and various studies have shown a large variability in the use of blood products among different centers and even among individual anesthesiologists within the same center.Unfortunately,despite the large number of OLTx performed each year,there is still paucity of large randomized,multicentre,and controlled studies which indicate how to prevent bleeding,the transfusion needs and thresholds,and the "evidence based" perioperative strategies to reduce the amount of transfusion.

Advantage of autologous blood transfusion in surgery for hepatocellular carcinoma

AIM: To evaluate the significance of autologous blood transfusion (AT) in reducing homologous blood transfusion (HT) in surgery for hepatocellular carcinoma (HCC). METHODS: The proportion of patients who received HT was compared between two groups determined by the time of AT introduction; period A (1991-1994, n = 93) and period B (1995-2000, n = 201). Multivariate logistic regression analysis was performed in order to identify independent significant predictors of the need for HT. We also investigated the impact of AT and HT on long-term postoperative outcome after curative surgery for HCC. RESULTS: The proportion of patients with HT was significantly lower in period B than period A (18.9% vs 60.2%, P < 0.0001). Multivariate logistic regression analysis identified AT administration as a significant independent predictor of the need for HT (P < 0.0001). Disease-free survival in patients with AT was comparable to that without any transfusion. Multivariate analysis identified HT administration as an independent significant factor for poorer disease-free survival (P = 0.0380). CONCLUSION: AT administration significantly decreased the need for HT. Considering the postoperative survival disadvantage of HT, AT administration could improve the long-term outcome of HCC patients.

Perfusionist strategies for blood conservation in pediatric cardiac surgery

There is increasing concern about the safety of homologous blood transfusion during cardiac surgery,and a restrictive transfusion practice is associated with improved outcome.Transfusion-free pediatric cardiac surgery is unrealistic for the vast majority of procedures in neonates or small infants;however,considerable progress has been made by using techniques that decrease the need for homologous blood products or even allow bloodless surgery in older infants and children.These techniques involve a decrease in prime volume by downsizing the bypass circuit with the help of vacuumassisted venous drainage,microplegia,autologous blood predonation with or without infusion of recombinant(erythropoietin),cell salvaging,ultrafiltration and retrograde autologous priming.The three major techniques which are simple,safe,efficient,and cost-effective are:a prime volume as small as possible,cardioplegia with negligible hydric balance and circuit residual blood salvaged without any alteration.Furthermore,these three techniques can be used for all the patients,including emergencies and small babies.In every pediatric surgical unit,a strategy to decrease or avoid blood bank transfusion must be implemented.A strategy to minimize transfusion requirement requires a combined effort involving the entire surgical team with pre-,peri-,and postoperative planning and management.

Perioperative visual loss after spine surgery

Perioperative visual loss(POVL) is an uncommon, but devastating complication that remains primarily associated with spine and cardiac surgery. The incidence and mechanisms of visual loss after surgery remain difficult to determine. According to the American Society of Anesthesiologists Postoperative Visual Loss Registry, the most common causes of POVL in spine procedures are the two different forms of ischemic optic neuropathy: anterior ischemic optic neuropathy and posterior ischemic optic neuropathy, accounting for 89% of the cases. Retinal ischemia, cortical blindness, and posterior reversible encephalopathy are also observed, but in a small minority of cases. A recent multicenter case control study has identified risk factors associated with ischemic optic neuropathy for patients undergoing prone spinal fusion surgery. These include obesity, male sex, Wilson frame use, longer anesthetic duration, greater estimated blood loss, and decreased percent colloid administration. These risk factors are thought to contribute to the elevation of venous pressure and interstitial edema, resulting in damage to the optic nerve by compression of the vessels that feed the optic nerve, venous infarction or direct mechanical compression. This review will expand on these findings as well as the recently updated American Society of Anesthesiologists practice advisory on POVL. There are no effectivetreatment options for POVL and the diagnosis is often irreversible, so efforts must focus on prevention and risk factor modification. The role of crystalloids versus colloids and the use of α-2 agonists to decrease intraocular pressure during prone spine surgery will also be discussed as a potential preventative strategy.