Development and validation of a machine learning-based early prediction model for massive intraoperative bleeding in patients with primary hepatic malignancies

BACKGROUND Surgical resection remains the primary treatment for hepatic malignancies,and intraoperative bleeding is associated with a significantly increased risk of death.Therefore,accurate prediction of intraoperative bleeding risk in patients with hepatic malignancies is essential to preventing bleeding in advance and providing safer and more effective treatment.AIM To develop a predictive model for intraoperative bleeding in primary hepatic malignancy patients for improving surgical planning and outcomes.METHODS The retrospective analysis enrolled patients diagnosed with primary hepatic malignancies who underwent surgery at the Hepatobiliary Surgery Department of the Fourth Hospital of Hebei Medical University between 2010 and 2020.Logistic regression analysis was performed to identify potential risk factors for intraoperative bleeding.A prediction model was developed using Python programming language,and its accuracy was evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Among 406 primary liver cancer patients,16.0%(65/406)suffered massive intraoperative bleeding.Logistic regression analysis identified four variables as associated with intraoperative bleeding in these patients:ascites[odds ratio(OR):22.839;P<0.05],history of alcohol consumption(OR:2.950;P<0.015),TNM staging(OR:2.441;P<0.001),and albumin-bilirubin score(OR:2.361;P<0.001).These variables were used to construct the prediction model.The 406 patients were randomly assigned to a training set(70%)and a prediction set(30%).The area under the ROC curve values for the model’s ability to predict intraoperative bleeding were 0.844 in the training set and 0.80 in the prediction set.CONCLUSION The developed and validated model predicts significant intraoperative blood loss in primary hepatic malignancies using four preoperative clinical factors by considering four preoperative clinical factors:ascites,history of alcohol consumption,TNM staging,and albumin-bilirubin score.Consequently,this model holds promise for enhancing individualised surgical planning.

Survival Analysis of Patients Undergoing Intraoperative Contrast-enhanced Ultrasound in the Surgical Treatment of Malignant Glioma

Objective:Complete resection of malignant gliomas is often challenging.Our previous study indicated that intraoperative contrast-enhanced ultrasound(ICEUS)could aid in the detection of residual tumor remnants and the total removal of brain lesions.This study aimed to investigate the survival rates of patients undergoing resection with or without the use of ICEUS and to assess the impact of ICEUS on the prognosis of patients with malignant glioma.Methods:A total of 64 patients diagnosed with malignant glioma(WHO grade HI and IV)who underwent surgery between 2012 and 2018 were included.Among them,29 patients received ICEUS.The effects of ICEUS on overall survival(OS)and progression-free survival(PFS)of patients were evaluated.A quantitative analysis was performed to compare ICEUS parameters between gliomas and the surrounding tissues.Results:The ICEUS group showed better survival rates both in OS and PFS than the control group.The univariate analysis revealed that age,pathology and ICEUS were significant prognostic factors for PFS,with only age being a significant prognostic factor for OS.In multivariate analysis,age and ICEUS were significant prognostic factors for both OS and PFS.The quantitative analysis showed that the intensity and transit time of microbubbles reaching the tumors were significantly different from those of microbubbles reaching the surrounding tissue.Conclusion:ICEUS facilitates the identification of residual tumors.Age and ICEUS are prognostic factors for malignant glioma surgery,and use of ICEUS offers a better prognosis for patients with malignant glioma.

Will partial splenic embolization followed by splenectomy increase intraoperative bleeding?

BACKGROUND Partial splenic embolization(PSE)has been suggested as an alternative to splenectomy in the treatment of hypersplenism.However,some patients may experience recurrence of hypersplenism after PSE and require splenectomy.Currently,there is a lack of evidence-based medical support regarding whether preoperative PSE followed by splenectomy can reduce the incidence of complications.AIM To investigate the safety and therapeutic efficacy of preoperative PSE followed by splenectomy in patients with cirrhosis and hypersplenism.METHODS Between January 2010 and December 2021,321 consecutive patients with cirrhosis and hypersplenism underwent splenectomy at our department.Based on whether PSE was performed prior to splenectomy,the patients were divided into two groups:PSE group(n=40)and non-PSE group(n=281).Patient characteristics,postoperative complications,and follow-up data were compared between groups.Propensity score matching(PSM)was conducted,and univariable and multivariable analyses were used to establish a nomogram predictive model for intraoperative bleeding(IB).The receiver operating characteristic curve,Hosmer-Lemeshow goodness-of-fit test,and decision curve analysis(DCA)were employed to evaluate the differentiation,calibration,and clinical performance of the model.RESULTS After PSM,the non-PSE group showed significant reductions in hospital stay,intraoperative blood loss,and operation time(all P=0.00).Multivariate analysis revealed that spleen length,portal vein diameter,splenic vein diameter,and history of PSE were independent predictive factors for IB.A nomogram predictive model of IB was constructed,and DCA demonstrated the clinical utility of this model.Both groups exhibited similar results in terms of overall survival during the follow-up period.CONCLUSION Preoperative PSE followed by splenectomy may increase the incidence of IB and a nomogram-based prediction model can predict the occurrence of IB.

Risk factors associated with intraoperative persistent hypotension in pancreaticoduodenectomy

BACKGROUND Intraoperative persistent hypotension(IPH)during pancreaticoduodenectomy(PD)is linked to adverse postoperative outcomes,yet its risk factors remain unclear.AIM To clarify the risk factors associated with IPH during PD,ensuring patient safety in the perioperative period.METHODS A retrospective analysis of patient records from January 2018 to December 2022 at the First Affiliated Hospital of Nanjing Medical University identified factors associated with IPH in PD.These factors included age,gender,body mass index,American Society of Anesthesiologists classification,comorbidities,medication history,operation duration,fluid balance,blood loss,urine output,and blood gas parameters.IPH was defined as sustained mean arterial pressure<65 mmHg,requiring prolonged deoxyepinephrine infusion for>30 min despite additional deoxyepinephrine and fluid treatments.RESULTS Among 1596 PD patients,661(41.42%)experienced IPH.Multivariate logistic regression identified key risk factors:increased age[odds ratio(OR):1.20 per decade,95%confidence interval(CI):1.08-1.33](P<0.001),longer surgery duration(OR:1.15 per additional hour,95%CI:1.05-1.26)(P<0.01),and greater blood loss(OR:1.18 per 250-mL increment,95%CI:1.06-1.32)(P<0.01).A novel finding was the association of arterial blood Ca^(2+)<1.05 mmol/L with IPH(OR:2.03,95%CI:1.65-2.50)(P<0.001).CONCLUSION IPH during PD is independently associated with older age,prolonged surgery,increased blood loss,and lower plasma Ca^(2+).

Exploring the Need and Strategy for Intraoperative Freezing to Identify Metastatic Adenocarcinoma of the Lungs

Objective: To explore the necessity and strategy of intraoperative freezing to identify primary and metastatic adenocarcinoma of the lung. Methods: This study retrospectively analyzes the impact of failing to make a definitive diagnosis of metastatic adenocarcinoma of the lung on the clinical surgical approach in four cases of intraoperative freezing. It also examines the reasons for this failure and reviews the relevant literature. Results: All 4 cases of intraoperative freezing were diagnosed as invasive adenocarcinoma, and none of them made a definitive diagnosis of metastatic adenocarcinoma. Conclusion: It is difficult to confirm the diagnosis of metastatic adenocarcinoma of the lung by intraoperative frozen section, and the combination of patient history, rapid immunohistochemistry, and histological morphology of intraoperative frozen section for its identification can guide the surgeon to adjust the surgical approach in time and provide evidence for the establishment of surgical protocols for reference.

Microstructural morphology and visual acuity outcome in eyes with epiretinal membrane before,during,and after membrane peeling in intraoperative optical coherence tomography assisted macular surgery

AIM:To measure the difference of intraoperative central macular thickness(CMT)before,during,and after membrane peeling and investigate the influence of intraoperative macular stretching on postoperative best corrected visual acuity(BCVA)outcome and postoperative CMT development.METHODS:A total of 59 eyes of 59 patients who underwent vitreoretinal surgery for epiretinal membrane was analyzed.Videos with intraoperative optical coherence tomography(OCT)were recorded.Difference of intraoperative CMT before,during,and after peeling was measured.Pre-and postoperatively obtained BCVA and spectral-domain OCT images were analyzed.RESULTS:Mean age of the patients was 70±8.13y(range 46-86y).Mean baseline BCVA was 0.49±0.27 log MAR(range 0.1-1.3).Three and six months postoperatively the mean BCVA was 0.36±0.25(P=0.01 vs baseline)and 0.38±0.35(P=0.08 vs baseline)log MAR respectively.Mean stretch of the macula during surgery was 29%from baseline(range 2%-159%).Intraoperative findings of macular stretching did not correlate with visual acuity outcome within 6mo after surgery(r=-0.06,P=0.72).However,extent of macular stretching during surgery significantly correlated with less reduction of CMT at the fovea centralis(r=-0.43,P<0.01)and 1 mm nasal and temporal from the fovea(r=-0.37,P=0.02 and r=-0.50,P<0.01 respectively)3mo postoperatively.CONCLUSION:The extent of retinal stretching during membrane peeling may predict the development of postoperative central retinal thickness,though there is no correlation with visual acuity development within the first 6mo postoperatively.

Combined and intraoperative risk modelling for oesophagectomy:A systematic review

BACKGROUND Oesophageal cancer is the eighth most common malignancy worldwide and is associated with a poor prognosis.Oesophagectomy remains the best prospect for a cure if diagnosed in the early disease stages.However,the procedure is associated with significant morbidity and mortality and is undertaken only after careful consideration.Appropriate patient selection,counselling and resource allocation is essential.Numerous risk models have been devised to guide surgeons in making these decisions.AIM To evaluate which multivariate risk models,using intraoperative information with or without preoperative information,best predict perioperative oesophagectomy outcomes.METHODS A systematic review of the MEDLINE,EMBASE and Cochrane databases was undertaken from 2000-2020.The search terms used were[(Oesophagectomy)AND(Model OR Predict OR Risk OR score)AND(Mortality OR morbidity OR complications OR outcomes OR anastomotic leak OR length of stay)].Articles were included if they assessed multivariate based tools incorporating preoperative and intraoperative variables to forecast patient outcomes after oesophagectomy.Articles were excluded if they only required preoperative or any post-operative data.Studies appraising univariate risk predictors such as preoperative sarcopenia,cardiopulmonary fitness and American Society of Anesthesiologists score were also excluded.The review was conducted following the preferred reporting items for systematic reviews and meta-analyses model.All captured risk models were appraised for clinical credibility,methodological quality,performance,validation and clinical effectiveness.RESULTS Twenty published studies were identified which examined eleven multivariate risk models.Eight of these combined preoperative and intraoperative data and the remaining three used only intraoperative values.Only two risk models were identified as promising in predicting mortality,namely the Portsmouth physiological and operative severity score for the enumeration of mortality and morbidity(POSSUM)and POSSUM scores.A further two studies,the intraoperative factors and Esophagectomy surgical Apgar score based nomograms,adequately forecasted major morbidity.The latter two models are yet to have external validation and none have been tested for clinical effectiveness.CONCLUSION Despite the presence of some promising models in forecasting perioperative oesophagectomy outcomes,there is more research required to externally validate these models and demonstrate clinical benefit with the adoption of these models guiding postoperative care and allocating resources.

Efficacy and outcome of extensive intraoperative peritoneal lavage plus surgery vs surgery alone with advanced gastric cancer patients

BACKGROUND Gastric cancer(GC)is one of the most common malignant tumors.After resection,one of the major problems is its peritoneal dissemination and recurrence.Some free cancer cells may still exist after resection.In addition,the surgery itself may lead to the dissemination of tumor cells.Therefore,it is necessary to remove residual tumor cells.Recently,some researchers found that extensive intraoperative peritoneal lavage(EIPL)plus intraperitoneal chemotherapy can improve the prognosis of patients and eradicate peritoneal free cancer for GC patients.However,few studies explored the safety and long-term outcome of EIPL after curative gastrectomy.AIM To evaluate the efficacy and long-term outcome of advanced GC patients treated with EIPL.METHODS According to the inclusion and exclusion criteria,a total of 150 patients with advanced GC were enrolled in this study.The patients were randomly allocated to two groups.All patients received laparotomy.For the non-EIPL group,peritoneal lavage was washed using no more than 3 L of warm saline.In the EIPL group,patients received 10 L or more of saline(1 L at a time)before the closure of the abdomen.The surviving rate analysis was compared by the Kaplan-Meier method.The prognostic factors were carried out using the Cox appropriate hazard pattern.RESULTS The basic information in the EIPL group and the non-EIPL group had no significant difference.The median follow-up time was 30 mo(range:0-45 mo).The 1-and 3-year overall survival(OS)rates were 71.0%and 26.5%,respectively.The symptoms of ileus and abdominal abscess appeared more frequently in the non-EIPL group(P<0.05).For the OS of patients,the EIPL,Borrmann classification,tumor size,N stage,T stage and vascular invasion were significant indicators.Then multivariate analysis revealed that EIPL,tumor size,vascular invasion,N stage and T stage were independent prognostic factors.The prognosis of the EIPL group was better than the non-EIPL group(P<0.001).The 3-year survival rate of the EIPL group(38.4%)was higher than the non-EIPL group(21.7%).For the recurrence-free survival(RFS)of patients,the risk factor of RFS included EIPL,N stage,vascular invasion,type of surgery,tumor location,Borrmann classification,and tumor size.EIPL and tumor size were independent risk factors.The RFS curve of the EIPL group was better than the non-EIPL group(P=0.004),and the recurrence rate of the EIPL group(24.7%)was lower than the non-EIPL group(46.4%).The overall recurrence rate and peritoneum recurrence rate in the EIPL group was lower than the non-EIPL group(P<0.05).CONCLUSION EIPL can reduce the possibility of perioperative complications including ileus and abdominal abscess.In addition,the overall survival curve and RFS curve were better in the EIPL group.

Current use of intraoperative ultrasound in modern liver surgery

Ultrasound plays an important role not only in preoperative diagnosis but also in intraoperative guidance for liver surgery.Intraoperative ultrasound(IOUS)has become an indispensable tool for modern liver surgeons,especially for minimally invasive surgeries,partially substituting for the surgeon’s hands.In fundamental mode,Doppler mode,contrast enhancement,elastography,and real-time virtual sonography,IOUS can provide additional real-time information regarding the intrahepatic anatomy,tumor site and characteristics,macrovascular invasion,resection margin,transection plane,perfusion and outflow of the remnant liver,and local ablation efficacy for both open and minimally invasive liver resections.Identification and localization of intrahepatic lesions and surrounding structures are crucial for performing liver resection,preserving the adjacent vital vascular and bile ducts,and sparing the functional liver parenchyma.Intraoperative ultrasound can provide critical information for intraoperative decision-making and navigation.Therefore,all liver surgeons must master IOUS techniques,and IOUS should be included in the training of modern liver surgeons.Further investigation of the potential benefits and advances in these techniques will increase the use of IOUS in modern liver surgeries worldwide.This study comprehensively reviews the current use of IOUS in modern liver surgeries.

术中及围手术期血清iPTH监测对501例继发性甲状旁腺功能亢进患者手术效果的精准诊断研究——“Diagnostic Accuracy Study of Intraoperative and Perioperative Serum Intact PTH Level for Successful Parathyroidectomy in 501 Secondary Hyperparathyroidism Patients”的二

目的甲状旁腺切除术(parathyroidectomy,PTX)是继发性甲状旁腺功能亢进患者(secondary hyperparathyroidism,SHPT)的有效治疗方式,然而由于甲状旁腺位置和数目异常的存在,部分患者术后SHPT仍持续存在。本研究探讨PTX患者术中及围手术期血清全段甲状旁腺激素(intact parathyroid hormone,iPTH)监测对手术效果精准诊断的意义。方法记录501例行甲状旁腺全切+自体前臂移植术(不伴胸腺切除)的慢性肾脏病患者的术中及围手术期血清iPTH值。术后一周内患者血清iPTH≤50 pg/ml为手术成功;若>50 pg/ml则在6月内进行随访,随访血清iPTH<300 pg/mL即为手术成功,否则为SHPT持续存在。结果 433例(86.4%)患者手术成功,49例(9.8%)患者SHPT持续存在,19例(3.8%)患者缺乏有效随访归为手术效果未知组。肝炎(n=204)与非肝炎(n=297)患者比较,基线血清iPTH水平及术中血清iPTH下降百分比无显著统计学差异(P>0.05)。受试者工作特征(receiver operating characteristic,ROC)曲线结果表明术后20分钟血清iPTH下降≥88.9%提示手术成功(曲线下面积0.909,敏感度78.6%,特异度88.5%)。术后4天血清iPTH≥147.4 pg/ml提示SHPT持续存在(曲线下面积0.998,敏感度100%,特异度99.5%)。结论甲状旁腺切除术中血清iPTH监测能提示甲状旁腺切除是否彻底,避免对患者不必要的探查,降低手术并发症的发生率。围手术期血清iPTH监测提示SHPT是否持续存在,对此类患者需密切随访、及时开始药物治疗或必要时再次手术。

Application of contrast-enhanced intraoperative ultrasonography in the decision-making about hepatocellular carcinoma operation

AIM:To evaluate the detection and differentiation ability of contrast-enhanced intraoperative ultrasonography(CE-IOUS) in hepatocellular carcinoma(HCC) operations.METHODS:Clinical data of 50 HCC patients were retrospective analyzed.The sensitivity,specificity,false negative and false positive rates of contrast enhanced magnetic resonance imaging(CE-MRI),IOUS and CEIOUS were calculated and compared.Surgical strategy changes due to CE-IOUS were analyzed.RESULTS:Lesions detected by CE-MRI,IOUS and CEIOUS were 60,97 and 85 respectively.The sensitivity,specificity,false negative rate,false positive rate of CEMRI were 98.2%,98.6%,98.6%,60.0%,respectively;for IOUS were 50.0%,90.9%,1.8%,1.4%,respectively;and for CE-IOUS were 1.4%,40.0%,50.0%,9.1%,respectively.The operation strategy of 9(9/50,18.0%) cases was changed according to the results of CE-IOUS.CONCLUSION:Compared with CE-MRI,CE-IOUS performs better in detection and differentiation of small metastasis and regenerative nodules.It plays an important role in the decision-making of HCC operation.

Predictive roles of intraoperative blood glucose for posttransplant outcomes in liver transplantation

Diabetogenic traits in patients undergoing liver transplantation(LT) are exacerbated intraoperatively by exogenous causes, such as surgical stress, steroids,blood transfusions, and catecholamines, which leadto intraoperative hyperglycemia. In contrast to the strict glucose control performed in the intensive care unit, no systematic protocol has been developed for glucose management during LT. Intraoperative blood glucose concentrations typically exceed 200 mg/dL in LT, and extreme hyperglycemia(> 300 mg/dL) is common during the neohepatic phase. Only a few retrospective studies have examined the relationship between intraoperative hyperglycemia and posttransplant complications, with reports of infectious complications or mortality. However, no prospective studies have been conducted regarding the influence of intraoperative hyperglycemia in LT on post-transplant outcome. In addition to absolute blood glucose values,the temporal patterns in blood glucose levels during LT may serve as prognostic features. Persistent neohepatic hyperglycemia(without a decline) throughout LT is a useful indicator of early graft dysfunction. Moreover,intraoperative variability in glucose levels may predict the need for reoperation for hemorrhage after LT.Thus, there is an urgent need for guidelines for glucose control in these patients, as well as prospective studies on the impact of glucose control on various posttransplant complications. This report highlights some of the recent studies related to perioperative blood glucose management focused on LT and liver disease.

Impact of intraoperative blood loss on survival after curative resection for gastric cancer

AIM:To elucidate the potential impact of intraoperative blood loss(IBL)on long-term survival of gastric cancer patients after curative surgery.METHODS:A total of 845 stageⅠ-Ⅲgastric cancer patients who underwent curative gastrectomy between January 2003 and December 2007 in our center were enrolled in this study.Patients were divided into 3groups according to the amount of IBL:group 1(<200mL),group 2(200-400 mL)and group 3(>400 mL).Clinicopathological features were compared among the three groups and potential prognostic factors were analyzed.The Log-rank test was used to assess statistical differences between the groups.Independent prognostic factors were identified by the Cox proportional hazards regression model.Stratified analysis was used to investigate the impact of IBL on survival in each stage.Cancer-specific survival was also compared among the three groups by excluding deaths due to reasons other than gastric cancer.Finally,we explored the possible factors associated with IBL and identified the independent risk factors for IBL≥200 mL.RESULTS:Overall survival was significantly influenced by the amount of IBL.The 5-year overall survival rates were 51.2%,39.4%and 23.4%for IBL less than 200mL,200 to 400 mL and more than 400 mL,respectively(<200 mL vs 200-400 mL,P<0.001;200-400 mL vs>400 mL,P=0.003).Age,tumor size,Borrmann type,extranodal metastasis,tumour-node-metastasis(TNM)stage,chemotherapy,extent of lymphadenectomy,IBL and postoperative complications were found to be independent prognostic factors in multivariable analysis.Following stratified analysis,patients staged TNMⅠ-Ⅱand those with IBL less than 200 mL tended to have better survival than those with IBL not less than 200mL,while patients staged TNMⅢ,whose IBL was less than 400 mL had better survival.Tumor location,tumor size,TNM stage,type of gastrectomy,combined organ resection,extent of lymphadenectomy and year of surgery were found to be factors associated with the amount of IBL,while tumor location,type of gastrectomy,combined organ resection and year of surgery were independently associated with IBL≥200 mL.CONCLUSION:IBL is an independent prognostic factor for gastric cancer after curative resection.Reducing IBL can improve the long-term outcome of gastric cancer patients following curative gastrectomy.

Intraoperative acidosis is a new predictor for postoperative pancreatic fistula after pancreaticoduodenectomy

BACKGROUND： Early diagnosis of postoperative pancreatic fistula （POPF） is important for proper interventions. The pre- operative, intraoperative and early postoperative biochemical markers have predictive value of POPF. The present study was to evaluate several simple biochemical parameters in the pre- diction of POPF.

Laparoscopic ultrasonography as an alternative to intraoperative cholangiography during laparoscopic cholecystectomy

AIM To assess the role of laparoscopic ultrasound(LUS) as a substitute for intraoperative cholangiography(IOC) during cholecystectomy.METHODS We present a MEDLINE and Pub Med literature search, having used the key-words "laparoscopic intraoperative ultrasound" and "laparoscopic cholecystectomy". All relevant English language publications from 2000 to 2016 were identified, with data extracted for the role of LUS in the anatomical delineation of the biliary tract, detection of common bile duct stones(CBDS), prevention or early detection of biliary duct injury(BDI), and incidental findings during laparoscopic cholecystectomy. Data for the role of LUS vs IOC in complex situations(i.e., inflammatory disease/fibrosis) were specifically analyzed. RESULTS We report data from eighteen reports, 13 prospective non-randomized trials, 5 retrospective trials, and two meta-analyses assessing diagnostic accuracy, with one analysis also assessing costs, duration of the examination, and anatomical mapping. Overall, LUS was shown to provide highly sensitive mapping of the extra-pancreatic biliary anatomy in 92%-100% of patients, with more difficulty encountered in delineation of the intra-pancreatic segment of the biliary tract(73.8%-98%). Identification of vascular and biliary variations has been documented in two studies. Although inflammatory disease hampered accuracy, LUS was still advantageous vs IOC in patients with obscured anatomy. LUS can be performed before any dissection and repeated at will to guide the surgeon especially when hilar mapping is difficult due to fibrosis and inflammation. In two studies LUS prevented conversion in 91% of patients with difficult scenarios. Considering CBDS detection, LUS sensitivity and specificity were 76%-100% and 96.2%-100%, respectively. LUS allowed the diagnosis/treatment of incidental findings of adjacent organs. No valuable data for BDI prevention or detection could be retrieved, even if no BDI was documented in the reports analyzed. Literature analysis proved LUS as a safe, quick, non-irradiating, costeffective technique, which is comparatively well known although largely under-utilized, probably due to the perception of a difficult learning curve. CONCLUSION We highlight the advantages and limitations of laparoscopic ultrasound during cholecystectomy, and underline its value in difficult scenarios when the anatomy is obscured.

Intraoperative neurophysiological monitoring in spinal surgery

Recently, many surgeons have been using intraoperative neurophysiological monitoring(IOM) in spinal surgery to reduce the incidence of postoperative neurological complications, including level of the spinal cord, cauda equina and nerve root. Several established technologies are available and combined motor and somatosensory evoked potentials are considered mandatory for practical and successful IOM. Spinal cord evoked potentials are elicited compound potentials recorded over the spinal cord. Electrical stimulation is provoked on the dorsal spinal cord from an epidural electrode. Somatosensory evoked potentials assess the functional integrity of sensory pathways from the peripheral nerve through the dorsal column and to the sensory cortex. For identification of the physiological midline, the dorsal column mapping technique can be used. It is helpful for reducing the postoperative morbidity associated with dorsal column dysfunction when distortion of the normal spinal cord anatomy caused by an intramedullary cord lesion results in confusion in localizing the midline for the myelotomy. Motor evoked potentials(MEPs) consist of spinal, neurogenic and muscle MEPs. MEPs allow selective and specific assessment of the functional integrity of descending motor pathways, from the motor cortex to peripheral muscles. Spinal surgeons should understand the concept of the monitoring techniques and interpret monitoring records adequately to use IOM for the decision making during the surgery for safe surgery and a favorable surgical outcome.

Intraoperative radiofrequency ablation with or without tumorectomy for hepatocellular carcinoma in locations difficult for a percutaneous approach

BACKGROUND:Although hepatic resection is widely accepted as a proper modality for treating hepatocellular carcinoma(HCC),a majority of patients are unable to undergo surgical resection due to various tumor and patient factors.Radiofrequency ablation(RFA)has mostly been used as a therapeutic alternative to resection for treating HCC.The objective of this study was to evaluate the results of intraoperative RFA for HCCs in locations difficult for a percutaneous approach.METHODS:Eight patients(male,seven;age,49-67 years) with 8 HCCs in difficult locations were treated by intraoperative RFA.Six of the patients had local tumor progression after initial transarterial chemoembolization or ultrasound(US)guided percutaneous RFA.The locations of the tumors were hepatic dome in six patients,posterior subcapsule in one,and caudate lobe in one.The tumor size was 2.0 to 6.4 cm(mean,3.9 cm).Intraoperative RFA was performed at the tumor itself and an anticipated resection line under US guidance with 3 cm monopolar single or clustered internally cooled electrodes.Tumor resection was performed in six patients.One month later,treatment response was assessed by contrast material-enhanced computed tomography(CT).CT studies were performed every 2 or 3 months after RFA.RESULTS:RFA was technically successful in all tumors,and the contrast-enhanced CT images acquired one month later showed complete disappearance of tumor enhancement.One pneumothorax occurred.After a median follow-up of 18 months(range,6-30 months),no tumors showed local progression.During the follow-up period,four new recurrent tumors were observed in three patients.Four patients were alive at the time of this report and the other four died of hepatorenal syndrome,liver failure,and progression of new recurrent tumors.CONCLUSION:Intraoperative RFA with tumor resection can be an alterative treatment option for HCC in locations difficult for a percutaneous approach.

Intraoperative blood loss in orthotopic liver transplantation:The predictive factors

Liver transplantation has been associated with massive blood loss and considerable transfusion requirements. Bleeding in orthotopic liver transplantation is multifactorial. Technical difficulties inherent to this complex surgical procedure and pre operative derangements of the primary and secondary coagulation system are thought to be the principal causes of perioperative hemorrhage. Intraoperative practices such as massive fluid resuscitation and resulting hypothermia and hypocalcemia secondary to citrate toxicity further aggravate the preexisting coagulopathy and worsen the perioperative bleeding. Excessive blood loss and transfusion during orthotopic liver transplant are correlated with diminished graft survival and increased septic episodes and prolonged ICU stay. With improvements in surgical skills, anesthetic technique, graft preservation, use of intraoperative cell savers and overall perioperative management, orthotopic liver transplant is now associated with decreased intra operative blood losses. The purpose of this review is to discuss the risk factors predictive of increased intra operative bleeding in patients undergoing orthotopic liver transplant.

Intraoperative ERCP : 它在 laparoscopic 胆囊炎的时代有什么角色？

In the treatment of patients with symptomatic cholelithiasis and choledocholithiasis (CBDS) detected during intraoperative cholangiography (IOC),or when the preoperative study of a patient at intermediate risk for CBDS cannot be completed due to the lack of imaging techniques required for confirmation,or if they are available and yield contradictory radiological and clinical results,patients can be treated using intraoperative endoscopic retrograde cholangiopancreatography (ERCP) during the laparoscopic treatment or postoperative ERCP if the IOC finds CBDS.The choice of treatment depends on the level of experience and availability of each option at each hospital.Intraoperative ERCP has the advantage of being a single-stage treatment and has a significant success rate,an easy learning curve,low morbidity involving a shorter hospital stay and lower costs than the two-stage treatments (postoperative and preoperative ERCP).Intraoperative ERCP is also a good salvage treatment when preoperative ERCP fails or when total laparoscopic management also fails.

Controversy over the use of intraoperative blood salvage autotransfusion during liver transplantation for hepatocellular carcinoma patients

Intraoperative blood salvage autotransfusion (IBSA) is used in various surgical procedures. However, because of the risk of reinfusion of salvaged blood contaminated by tumor cells, the use of IBSA in hepatocellular carcinoma (HCC) patients undergoing liver transplantation (LT) is controversial. The critical points include whether tumor cells can be cleared by IBSA, whether IBSA increases the risk of recurrence or metastasis, and what are the indications for IBSA. Moreover, is it warranted to take the risk of tumor dissemination by using IBSA to avoid allogeneic blood transfusion? Do the remaining tumor cells after additional filtration by leukocyte depletion filters still possess potential tumorigenicity? Does IBSA always work well? We have reviewed the literature and tried to address these questions. The available data indicate that IBSA is safe in LT for HCC, but randomized, controlled and prospective trials are urgently required to clarify the uncertainty.