Risk of venous thromboembolism outweighs post-hepatectomy bleeding complications: analysis of 5651 National Surgical Quality Improvement Program patients

Utility of plasma D-dimer for diagnosis of venous thromboembolism after hepatectomy

BACKGROUND

Venous thromboembolism (VTE) is a potentially fatal complication of hepatectomy. The use of postoperative prophylactic anticoagulation in patients who have undergone hepatectomy is controversial because of the risk of postoperative bleeding. Therefore, we hypothesized that monitoring plasma D-dimer could be useful in the early diagnosis of VTE after hepatectomy.

AIM

To evaluate the utility of monitoring plasma D-dimer levels in the early diagnosis of VTE after hepatectomy.

METHODS

The medical records of patients who underwent hepatectomy at our institution between January 2017 and December 2020 were retrospectively analyzed. Patients were divided into two groups according to whether or not they developed VTE after hepatectomy, as diagnosed by contrast-enhanced computed tomography and/or ultrasonography of the lower extremities. Clinicopathological factors, including demographic data and perioperative D-dimer values, were compared between the two groups. Receiver operating characteristic curve analysis was performed to determine the D-dimer cutoff value. Univariate and multivariate analyses were performed using logistic regression analysis to identify significant predictors.

RESULTS

In total, 234 patients who underwent hepatectomy were, of whom (5.6%) were diagnosed with VTE following hepatectomy. A comparison between the two groups showed significant differences in operative time (529 vs 403 min, P = 0.0274) and blood loss (530 vs 138 mL, P = 0.0067). The D-dimer levels on postoperative days (POD) 1, 3, 5, 7 were significantly higher in the VTE group than in the non-VTE group. In the multivariate analysis, intraoperative blood loss of > 275 mL [odds ratio (OR) = 5.32, 95% confidence interval (CI): 1.05-27.0, P = 0.044] and plasma D-dimer levels on POD 5 ≥ 21 μg/mL (OR = 10.1, 95%CI: 2.04-50.1, P = 0.0046) were independent risk factors for VTE after hepatectomy.

CONCLUSION

Monitoring of plasma D-dimer levels after hepatectomy is useful for early diagnosis of VTE and may avoid routine prophylactic anticoagulation in the postoperative period.

Risk factors of venous thromboembolism for liver tumors: a systematic review and meta-analysis

BACKGROUND

Venous thromboembolism (VTE) is a significant complication in liver tumors patients, and understanding the associated risk factors is essential for effective risk assessment, prevention, and management strategies. This systematic review and meta-analysis aimed to identify key risk factors and their clinical implications for VTE in liver tumors patients.

METHODS

A comprehensive search of multiple databases was conducted to identify relevant studies. Eligible studies were selected, and odds ratios (ORs) and 95% confidence intervals (CIs) were extracted and synthesized for meta-analysis.

RESULTS

A total of 11 studies involving 73,652 liver tumors patients and 2049 VTE cases were included. The analysis identified several significant risk factors for VTE in liver tumors patients. Age (≥65 years), male gender, high BMI, diabetes, hepatitis B and C infections, elevated D-dimer and AST levels, reduced albumin levels, and MELD score were all associated with increased VTE risk.

CONCLUSION

This systematic review and meta-analysis revealed several key risk factors for VTE in liver tumors patients, these findings highlight the importance of risk assessment, prevention, and management strategies in this high-risk population. Further research with larger sample sizes and standardized methods is needed to strengthen the existing evidence and validate these findings.

An international survey of venous thromboembolic events and current practices of peri-operative VTE prophylaxis after living donor hepatectomy

BACKGROUND

Venous thromboembolic complications are an uncommon but significant cause of morbidity & mortality after live donor hepatectomy . The precise incidence of these events and the current practices of centers performing living donor liver transplantation worldwide are unknown.

METHODS

An online survey was shared amongst living donor liver transplantation centers containing questions regarding center activity, center protocols for donor screening, peri-operative thromboembolic prophylaxis and an audit of -perioperative venous thromboembolic events after live donor hepatectomy in the previous five years (2016-2020).

RESULTS

Fifty-one centers from twenty countries completed the survey. These centers had cumulatively performed 11500 living donor liver transplants between 2016-2020. All centers included pre-operative l assessment for thromboembolic risk amongst potential liver donors in their protocols. Testing for inherited prothrombotic conditions was performed by 58% of centers. Dual-mode prophylaxis was the most common practice (65%), while eight and four centers used single mode or no routine prophylaxis respectively. Twenty (39%) and 15 (29%) centers reported atleast one perioperative deep venous thrmobosis or pulmonary embolism event respectively. There was one donor mortality directly related to post-operative pulmonary embolism. Overall incidence of deep venous thrombosis and pulmonary embolism events was 3.65 and 1.74 per 1000 live donor hepatectomies respectively. Significant variations in center practices and incidence of thromboembolic events was identified in the survey primarily divided along world regions. 75% of participating centers agreed on the need for clear international guidelines.

CONCLUSION

Venous thromboembolic events after live donor hepatectomy are an uncommon but important cause of donor morbidity. There is significant variation in practice among centers. Evidence-based guidelines regarding risk assessment, and peri-operative prophylaxis are needed.

Thromboelastographic results and hypercoagulability in dogs with surgically treated hepatocellular adenoma and carcinoma: A Veterinary Society of Surgical Oncology prospective study

BACKGROUND

The most common haemostatic abnormality in dogs with cancer is hypercoagulability. A transient hypercoagulability has been documented in people with hepatocellular carcinoma (HCC) that resolves within weeks following hepatic tumour resection.

OBJECTIVE

The objective was to compare the haemostatic status of dogs with liver tumours and healthy control dogs, by comparing coagulation and thromboelastography (TEG) measurements at three time points.

METHODS

Liver tumour and healthy control dogs receiving surgery for liver lobectomy and ovariohysterectomy, respectively, were prospectively enrolled. All dogs had blood collected at three time points: pre-operative, 24 h post-operative and ~2 weeks post-operative. Haematological and haemostatic values were compared across time points in each group using repeated measures ANOVA tests.

RESULTS

Ten and eight dogs were enrolled for the liver and control groups, respectively. Platelet count was significantly higher in the liver group than the control group at all time points, but within the normal range (pre-operative: 438.7 vs. 300.9 × 109 /L, p = .0078; 24 h post-operative: 416.2 vs. 283.9 × 109 /L, p = .0123; 10-14 days post-operative: 524.6 vs. 317.3 × 109 /L, p = .0072). The measure of the overall coagulant state (G-value) was significantly increased for the liver group compared to the control group at all time points (pre-operative: 15.6 vs. 8.6 d/sc, p = .0003; 24 h post-operative: 18.3 vs. 11.2 d/sc, p = .039; 10-14 days post-operative: 15.1 vs. 9.6 d/sc, p = .015).

CONCLUSION

The liver group was hypercoagulable based on elevated G-values at all time points compared to the control group. This hypercoagulability was attributed to the effect of hepatic tumours alone, and not secondary to surgery and anaesthesia.

Venous thromboembolism and bleeding after hepatectomy: role and impact of risk adjusted prophylaxis

Venous thromboembolism (VTE) occurs in 2-6% of post-hepatectomy patients and is associated with increased mortality and morbidity. The use of VTE risk assessment models in hepatectomy cases remains unclear. Our study aimed to determine the use and impact of Caprini guideline indicated VTE prophylaxis following hepatectomy. Hepatectomy cases performed during 2016-2021 were included. Caprini score and VTE prophylaxis were determined retroactively, and VTE prophylaxis was categorized as appropriate or inappropriate. The primary outcome was the receipt of appropriate prophylaxis, and secondary outcomes were postoperative VTE and bleeding. Statistical analyses included Fisher Exact test, Kruskal-Wallis, Pearson Chi-Square test, and multivariate regression models. R Statistical software was used for analysis. A p-value < 0.05 or 95% Confidence Interval (CI) excluding 1 was considered significant. A total of 1955 hepatectomy cases were analyzed. Patient demographics were similar between study cohorts. Inpatient, 30- and 90-day VTE rates were 1.28%, 0.56%, and 1.24%, respectively. By Caprini guidelines, 59% and 4.3% received appropriate in-hospital and discharged VTE prophylaxis, respectively. Inpatient VTE (4.5-fold) and mortality (9.5-fold) were lower in patients receiving appropriate prophylaxis. All discharged VTE and mortality occurred in patients not receiving appropriate prophylaxis. Inpatient, 30- and 90-day bleeding rates were 8.4%, 0.62%, and 0.68%, respectively. Appropriate prophylaxis did not increase postoperative bleeding. Increasing Caprini score inversely correlated with receiving appropriate prophylaxis (OR 0.38, CI 0.31-0.46) at discharge, and appropriate prophylaxis did not correlate with bleeding risk (OR 0.79, CI 0.57-1.12). Caprini guideline indicated prophylaxis resulted in reduced VTE complications without increasing bleeding risk.

Rate of prophylactic anti-Xa achievement and impact on venous thromboembolism following oncologic hepato-pancreatico-biliary surgery: A prospective cohort study

BACKGROUND

Hepato-pancreatico-biliary (HPB) patients experience competing risk of venous thromboembolism (VTE) and bleeding. We sought to evaluate the effect of anti-Xa levels on VTE and bleeding, and to characterize factors associated with subprophylaxis.

METHODS

This prospective cohort study evaluated adult HPB surgical patients; cohorts were described by anti-Xa levels as subprophylactic (<0.2 IU/mL), prophylactic (0.2-0.5 IU/mL), and supraprophylactic (>0.5 IU/mL). Primary outcome evaluated bleeding and VTE complications. Secondary outcomes evaluated factors associated with subprophylaxis.

RESULTS

We included 157 patients: 68 (43.6%) attained prophylactic anti-Xa and 89 (56.7%) were subprophylactic. Subprophylactic patients experienced more VTE compared to prophylactic patients (6.9% vs 0%; p = 0.028) without differences in bleeding complications (14.6% vs 5.9%; p = 0.081). Factors associated with subprophylactic anti-Xa included female sex (OR 2.90, p = 0.008), and Caprini score (OR 1.30, p = 0.035). Enoxaparin was protective against subprophylaxis compared to tinzaparin (OR 0.43, p = 0.029).

CONCLUSIONS

Many HPB patients have subprophylactic anti-Xa levels, placing them at risk of VTE. Enoxaparin may be preferential, however, studies evaluating optimized prophylaxis are needed.

Venous thromboembolism (VTE) after open hepatectomy compared to minimally invasive liver resection: a systematic review and meta-analysis

BACKGROUND

Even though the risk of postoperative venous thromboembolism (VTE) after liver resection is well recognized, the association between surgical approach and VTE risk is unknown. This study aims to compare VTE rates following open liver resection (OLR) and minimally invasive liver resection (MILR).

METHODS

MEDLINE, Web Of Sciences and EMBASE databases were interrogated to identify eligible studies published between February 2016 and August 2022. Studies were considered suitable if they reported a comparison between OLR and MILR (including laparoscopic liver resection [LLR] or robotic liver resection [RLR]).

RESULTS

Fourteen studies including 11 356 patients met the inclusion criteria. 5622 patients underwent OLR and 5734 patients underwent MILR. The VTE rate was higher among patients who underwent OLR compared to MILR (2.8% vs 1.4%, OR (95% CI) = 1.84, p=<00001). Similarly, the subgroup analysis showed a higher rate of deep venous thrombosis (DVT) (1.4% vs 0.7%, OR (95% CI) = 1.98, p = 0.02) and pulmonary embolism (PE) (1.3% vs 0.7%, OR (95% CI) = 1.88, p = 0.002) in patients who underwent OLR compared to MILR.

DISCUSSION

Patients who undergo open hepatectomy have a higher incidence of postoperative VTE when compared to those undergoing minimally invasive liver resection. This finding was consistent for both DVT and PE.

Risk factors for hypercoagulability after laparoscopic hepatic haemangioma resection

Background

Laparoscopic hepatectomy with a small incision, light abdominal wall trauma and rapid postoperative recovery has been widely used in the surgical treatment of benign liver diseases. However, the occurrence of complications, such as deep-vein thrombosis, associated with laparoscopic techniques has raised concerns. This study aimed to investigate the factors influencing the development of a hypercoagulable state in patients following laparoscopic hepatic haemangioma resection.

Materials and Methods

Between 2017 and 2019, 78 patients to be treated by laparoscopic hepatic haemangioma resection were selected prospectively for the study. The differences in relevant clinical factors between patients with and without blood hypercoagulability at 24 h after surgery were compared, and the factors influencing the development of blood hypercoagulability after surgery were analysed.

Results

The study included 78 patients, split into the hypercoagulable group (n = 27) and nonhypercoagulable group (n = 51). Compared with patients who did not develop blood hypercoagulability, patients who did had significantly higher preoperative levels of fibrinogen (Fib), D-dimer (D-Di), fibrinogen degradation products (FDP), platelet count (PLT), low-density lipoprotein cholesterol (LDL-C) and history of hyperlipidaemia whereas high-density lipoprotein cholesterol (HDL-C) levels were significantly lower (P < 0.05.) in hypercoagulable group. Univariate and multifactorial logistic regression analyses showed that a history of hyperlipidaemia, Fib ≥3.83 g/L, D-Di ≥9.12 μg/ml, FDP ≥14.64 μg/ml, PLT ≥292 × 109/L, HDL-C ≥1.25 mmol/L and LDL-C ≥2.03 mmol/L was the most common independent risk factors for the development of a hypercoagulable state of blood in patients after laparoscopic hepatic haemangioma resection (P < 0.05).

Conclusion

For patients undergoing laparoscopic hepatic haemangioma resection, attention should be paid to the development of a hypercoagulable state in those with the risk factors described in this study.

Deep vein thrombosis after open hepatectomy or other major upper abdominal surgery in Taiwan: A prospective and cross-sectional study relevant to the issue of pharmacological thromboprophylaxis

BACKGROUD/PURPOSE

Venous thromboembolism, including deep vein thrombosis (DVT) and pulmonary embolism (PE), is an important complication in patients who underwent open hepatic surgery as well as other major upper abdominal surgery. This study aims to investigate the occurrence of postoperative DVT without pharmacological thromboprophylaxis in such cohorts in Taiwan.

METHODS

This is a prospective, cross-sectional cohort study conducted from March 2010 to December 2011. Patients who underwent major upper abdominal surgery, including open hepatectomy, were enrolled. Color duplex compression ultrasonography (CUS) was used to detect DVT. Symptomatic PE was excluded if there were no suggestive respiratory symptoms or sudden death. Relevant clinicopathological and surgical information of each patient was collected and analyzed.

RESULTS

195 patients (118 male and 77 female) were enrolled, with a median age of 63.6 years. The majority (169/195, 88.7%) were treated for active malignancy. Totally 147 patients received open hepatectomy. Only one asymptomatic and distal postoperative DVT event was identified by CUS, which occurred on a 73-year-old female patient who received a left lateral segmental hepatectomy for removing the advanced hepatocellular carcinoma (pathologic stage, T3aN0M0). No cases of symptomatic PE or sudden death were observed. No correlation between DVT and precipitating factor was demonstrated in our cohort.

CONCLUSION

Without pharmacological thromboprophylaxis, a low rate of postoperative DVT among patients undergoing open hepatectomy (0.7%, 1/147) or major upper abdominal surgery (0.5%, 1/195) in Taiwan was reported. A distinctively regional role of pharmacological thromboprophylaxis for hepatic surgery was also suggested by our data.

Peri-operative thrombophilia in patients undergoing liver resection for colorectal metastases

BACKGROUND

Routine chemical venous thromboembolism (VTE) prophylaxis for liver surgery remains controversial, and often delayed post-operatively due to perceived bleeding risk. This study asked whether patients undergoing hepatectomy for colorectal metastases (CRM) were at risk from VTE pre-operatively, and the impact of hepatectomy on that risk.

METHODS

Single-centre prospective observational cohort study of patients undergoing open hepatectomy for CRM, comparing pre-, peri- and post-operative haemostatic variables.

RESULTS

Of 336 hepatectomies performed October 2017-December 2019, 60 resections in 57 patients were recruited. There were 28 (46.7%) major resections, with median (interquartile range [IQR]) blood loss 150.0 (76.3-263.7) mls, no blood transfusions, post-operative VTE events or deaths. Patients were prothrombotic pre-operatively (high median factor VIIIC and increased thrombin generation velocity index), an effect exacerbated post-hepatectomy. Major hepatectomies had a significantly greater median drop in Protein C, rise in Factor VIIIC and von Willebrand Factor, versus minor resections (p = 0.001, 0.005, 0.001 respectively). Patients with parenchymal transection times greater than median (40 min), had significantly increased median (IQR) PMBC-TFmRNA expression [1.65(0.93-2.70)2ddCt], versus quicker transections [0.99(0.69-1.28)2ddCt, p = 0.020].

CONCLUSIONS

Patients with CRM are prothrombotic pre-operatively, an effect exacerbated by hepatectomy, particularly longer, complex resections, suggesting chemical thromboprophylaxis be considered early in the patient pathway.

Post-hepatectomy liver failure prediction and prevention: Development of a nomogram containing postoperative anticoagulants as a risk factor

INTRODUCTION AND OBJECTIVES

Posthepatectomy liver failure (PHLF) is a serious complication after hepatectomy, and its effective methods for preoperative prediction are lacking. Here, we aim to identify predictive factors and build a nomogram to evaluate patients' risk of developing PHLF.

PATIENTS AND METHODS

A retrospective review of a training cohort, including 199 patients who underwent hepatectomy at the Shanghai Eastern Hepatobiliary Surgery Hospital, was conducted. Independent risk variables for PHLF were identified using multivariate analysis of perioperative variables, and a nomogram was used to build a predictive model. To test the predictive power, a prospective study in which a validation cohort of 71 patients was evaluated using the nomogram. The prognostic value of this nomogram was evaluated by the C-index.

RESULTS

Independent risk variables for PHLF were identified from perioperative variables. In multivariate analysis of the training cohort, tumor number, Pringle maneuver, blood loss, preoperative platelet count, postoperative ascites and use of anticoagulant medications were determined to be key risk factors for the development of PHLF, and they were selected for inclusion in our nomogram. The nomogram showed a 0.911 C-index for the training cohort. In the validation cohort, the nomogram also showed good prognostic value for predicting PHLF. The validation cohort was used with similarly successful results to evaluate risk in two previously published study models with calculated C-indexes of 0.718 and 0.711.

CONCLUSION

Our study establishes for the first time a novel nomogram that can be used to identify patients at risk of developing PHLF.

Post-hepatectomy venous thromboembolism: a systematic review with meta-analysis exploring the role of pharmacological thromboprophylaxis

PURPOSE

Patients undergoing hepatectomy are at moderate-to-high risk of venous thromboembolism (VTE). This study critically examines the efficacy of combining pharmacological (PTP) and mechanical thromboprophylaxis (MTP) versus only MTP in reducing VTE events against the risk of hemorrhagic complications.

METHODS

A systematic review of major reference databases was undertaken, and a meta-analysis was performed using common-effects model. Risk of bias assessment was performed using Newcastle-Ottawa scale. Trial sequential analysis (TSA) was used to assess the precision and conclusiveness of the results.

RESULTS

8 studies (n = 4238 patients) meeting inclusion criteria were included in the analysis. Use of PTP + MTP was found to be associated with significantly lower VTE rates compared to only MTP (2.5% vs 5.3%; pooled RR 0.50, p = 0.03, I² = 46%) with minimal type I error. PTP + MTP was not associated with an increased risk of hemorrhagic complications (3.04% vs 1.9%; pooled RR 1.54, p = 0.11, I² = 0%) and had no significant impact on post-operative length of stay (12.1 vs 10.8 days; pooled MD - 0.66, p = 0.98, I² = 0%) and mortality (2.9% vs 3.7%; pooled RR 0.73, p = 0.33, I² = 0%).

CONCLUSION

Despite differences in the baseline patient characteristics, extent of hepatectomy, PTP regimens, and heterogeneity in the pooled analysis, the current study supports the use of PTP in post-hepatectomy patients (grade of recommendation: strong) as the combination of PTP + MTP is associated with a significantly lower incidence of VTE (level of evidence, moderate), without an increased risk of post-hepatectomy hemorrhage (level of evidence, low).

Perioperative coagulation profile in major liver resection for cancer: a prospective observational study

Hepatectomy induced coagulation disturbances have been well studied over the past decade. Cumulative evidence supports the superiority of global coagulation analysis compared to conventional coagulation tests (i.e. PT or aPTT) for clinical decision making. Cancer, however, represents an acquired prothrombotic state and liver resection for cancer deserves a more thorough investigation. This prospective observational study was conducted to assess the perioperative coagulation status of patients undergoing major hepatectomies for primary or metastatic hepatic malignancy. Patients were followed up to the 10th postoperative day by serial measurements of conventional coagulation tests, plasma levels of coagulation factors and thrombin generation assay parameters. An abnormal coagulation profile was detected at presentation and included elevated FVIII levels, decreased levels of antithrombin and lag time prolongation in thrombin generation. Serial hematological data demonstrated increased vWF, FVIII, D-dimer, fibrinogen and decreased levels of natural anticoagulant proteins in the early postoperative period predisposing to a hypercoagulable state. The ratio of the anticoagulant protein C to the procoagulant FVIII was low at baseline and further declined postoperatively, indicating a prothrombotic state. Though no bleeding complications were reported, one patient experienced pulmonary embolism while under thromboprophylaxis. Overall, patients with hepatic carcinoma presenting for elective major hepatectomy may have baseline malignancy associated coagulation disturbances, aggravating the hypercoagulable state documented in the early postoperative period.

Predicting Intraoperative Difficulty of Open Liver Resections: The DIFF-scOR Study, An Analysis of 1393 Consecutive Hepatectomies From a French Multicenter Cohort

OBJECTIVE

The aim of this study was to build a predictive model of operative difficulty in open liver resections (LRs).

SUMMARY BACKGROUND DATA

Recent attempts at classifying open-LR have been focused on postoperative outcomes and were based on predefined anatomical schemes without taking into account other anatomical/technical factors.

METHODS

Four intraoperative variables were perceived by the authors as to reflect operative difficulty: operation and transection times, blood loss, and number of Pringle maneuvers. A hierarchical ascendant classification (HAC) was used to identify homogeneous groups of operative difficulty, based on these variables. Predefined technical/anatomical factors were then selected to build a multivariable logistic regression model (DIFF-scOR), to predict the probability of pertaining to the highest difficulty group. Its discrimination/calibration was assessed. Missing data were handled using multiple imputation.

RESULTS

HAC identified 2 clusters of operative difficulty. In the "Difficult LR" group (20.8% of the procedures), operation time (401 min vs 243 min), transection time (150 vs.63 minute), blood loss (900 vs 400 mL), and number of Pringle maneuvers (3 vs 1) were higher than in the "Standard LR" group. Determinants of operative difficulty were body weight, number and size of nodules, biliary drainage, anatomical or combined LR, transection planes between segments 2 and 4, 4, and 8 or 7 and 8, nonanatomical resections in segments 2, 7, or 8, caval resection, bilioentric anastomosis and number of specimens. The c-statistic of the DIFF-scOR was 0.822. By contrast, the discrimination of the DIFF-scOR to predict 90-day mortality and severe morbidity was poor (c-statistic: 0.616 and 0.634, respectively).

CONCLUSION

The DIFF-scOR accurately predicts open-LR difficulty and may be used for various purposes in clinical practice and research.

Association Between Operative Approach and Venous Thromboembolism Rate Following Hepatectomy: a Propensity-Matched Analysis

BACKGROUND

The use of minimally invasive approaches to hepatectomy has increased in recent years, but the risk of postoperative venous thromboembolism (VTE) is undefined. We aimed to compare VTE rates after open hepatectomy and minimally invasive hepatectomy using an administrative dataset.

STUDY DESIGN

Patients with primary or metastatic liver tumors were identified in the National Surgical Quality Improvement Program-targeted hepatectomy database (2016-2018). VTE was compared between patients who underwent open or minimally invasive hepatectomy after a propensity score matching of 1:1 for demographics, comorbidities, and operative factors.

RESULTS

A total of 6935 patients underwent open hepatectomy and 2237 underwent minimally invasive hepatectomy. After matching, there were 1968 patients per group without differences in demographics, comorbidities, or operative variables. Prior to matching, the VTE rate was higher among patients who underwent open hepatectomy (2.8% vs. 1.1%, p < 0.001), and open hepatectomy was independently associated with VTE (OR = 1.90, p = 0.006). The VTE rate remained higher among open hepatectomy compared to minimally invasive hepatectomy after matching (2.4% vs. 1.1%, p = 0.003). Open hepatectomy was associated with a higher VTE rate in patients undergoing minor (1.9 vs. 1.0%, p = 0.028) and major hepatectomy (5.0 vs. 1.9%, p = 0.045).

CONCLUSION

Patients who undergo an open hepatectomy for malignancy have a higher incidence of postoperative VTE compared to minimally invasive hepatectomy for both minor and major hepatectomy.

Incidence and Risk Factors of Venous Thromboembolism Following Hepatectomy for Colorectal Metastases: A Population-Based Retrospective Cohort Study

BACKGROUND

Incidence of venous thromboembolism (VTE) following hepatectomy for colorectal cancer (CRC) metastases is unclear. These patients may represent a vulnerable population due to increased tumour burden. We aim to identify the risk of VTE development in routine clinical practice among patients with resected CRC liver metastases, the associated risk factors, and its impact on survival.

METHODS

We conducted a population-based retrospective cohort study of Ontario patients undergoing hepatectomy for CRC metastases between 2002 and 2009 using linked universal healthcare databases. Multivariable logistic regression was used to estimate the association between patient characteristics and VTE risk at 30 and 90-days after surgery. Cox proportional-hazards regression was used to estimate the association between VTE and adjusted cancer specific (CSS) and overall survival (OS).

RESULTS

1310 patients were included with a mean age of 63 ± 11. 62% were male. 51% had one metastatic deposit. Major hepatectomy occurred in 64%. VTE occurred in 4% within 90 days of liver resection. Only longer length of stay was associated with VTE development (OR 6.88 (2.57-18.43), p <0.001 for 15-21 days versus 0-7 days). 38% of VTEs were diagnosed after discharge, comprising 1.52% of the total cohort. VTE was not associated with inferior CSS or OS.

CONCLUSIONS

Risk of VTE development in this population is similar to those undergoing hepatectomy for other indications, and to the risk following other cancer site resections where post-operative extended VTE prophylaxis is currently recommended. The number of VTEs occurring after discharge suggests there may be a role for extended VTE prophylaxis.

Construction and Validation of a Nomogram for Predicting the Risk of Deep Vein Thrombosis in Hepatocellular Carcinoma Patients After Laparoscopic Hepatectomy: A Retrospective Study

Background

The incidence of deep vein thrombosis (DVT) in hepatocellular carcinoma (HCC) patients after laparoscopic hepatectomy (LH) is unclear, and there is no effective method for DVT risk assessment in these patients.

Methods

The data from the total of 355 consecutive HCC patients who underwent LH were included. A DVT risk algorithm was developed using a training set (TS) of 243 patients, and its predictive performance was evaluated in both the TS and a validation set (VS) of 112 patients. The model was then used to develop a DVT risk nomogram (TRN).

Results

The incidence of DVT in the present study was 18.6%. Age, sex, body mass index (BMI), comorbidities and operative position were independent risk factors for DVT in the TS. The model based on these factors had a good predictive ability. In the TS, it had an area under the receiver operating characteristic (AUC) curve of 0.861, Hosmer-Lemeshow (H-L) goodness of fit p value of 0.626, sensitivity of 44.4%, specificity of 96.5%, positive predictive value (PPV) of 74.1%, negative predictive value (NPV) of 88.4%, and accuracy of 86.8%. In the VS, it had an AUC of 0.818, H-L p value of 0.259, sensitivity of 38.1%, specificity of 98.9%, PPV of 88.9%, NPV of 87.4%, and accuracy of 87.5%. The TRN performed well in both the internal and the external validation, indicating a good clinical application value. The TRN had a better predictive value of DVT than the Caprini score (p < 0.001).

Conclusion

The incidence of DVT after LH was high, and should not be neglected in HCC patients. The TRN provides an efficacious method for DVT risk evaluation and individualized pharmacological thromboprophylaxis.

Pre- vs. postoperative initiation of thromboprophylaxis in liver surgery

BACKGROUND

Thromboprophylaxis protocols in liver surgery vary greatly worldwide. Due to limited research, there is no consensus whether the administration of thromboprophylaxis should be initiated pre- or postoperatively.

METHODS

Patients undergoing liver resection in Helsinki University Hospital between 2014 and 2017 were reviewed retrospectively. Initiation of thromboprophylaxis was changed in the institution in the beginning of 2016 from postoperative to preoperative. Patients were classified into two groups for analyses: thromboprophylaxis initiated preoperatively (Preop-group) or postoperatively (Postop-group). The incidences of VTE and haemorrhage within 30 days of surgery were compared between these groups. Patients with permanent anticoagulation were excluded.

RESULTS

A total of 512 patients were included to the study (Preop, n = 253, Postop, n = 259). The incidence of VTE was significantly lower in the Preop-group compared to the Postop-group (3 (1.2%) vs. 25 (9.7%), P = <.0001), mainly due to a lower incidence of pulmonary embolisms in the Preop-group (3 (1.2%) vs. 24 (9.3%), P < .0001). The rates of posthepatectomy haemorrhage within 30 days of surgery were similar (Preop 38 (15.0%) vs. Postop 36 (13.9%), p = .719).

CONCLUSION

Initiating thromboprophylaxis preoperatively may reduce the incidence of postoperative VTE without affecting the incidence of posthepatectomy haemorrhage in patients undergoing liver resection.

Risk of venous thromboembolism in patients with elevated INR undergoing hepatectomy: an analysis of the American college of surgeons national surgical quality improvement program registry

BACKGROUND

Patients undergoing hepatectomy can have elevated INR and may have venous thromboembolism (VTE) prophylaxis withheld as a result. We sought to examine the association between preoperative INR elevation and VTE following hepatectomy.

METHODS

Hepatectomies captured in the American College of Surgeons National Surgical Quality Improvement Program registry between 2007 and 2016 were analyzed. Univariable and multivariable models examined the effect of incremental increases in preoperative INR on 30-day VTE, perioperative transfusion, serious morbidity, and mortality, adjusting for potential confounders.

RESULTS

We included 25,220 elective hepatectomies (62.4% partial lobectomies, 10.1% left hepatectomies, 18.6% right hepatectomies, 9.2% trisegmentectomies). The median age of the patients was 60 years and 49% were male. INR was elevated in 3089 patients (12.2%): 1.1-1.2 in 8.1%, 1.2-1.4 in 3.3%, and 1.4-2.0 in 0.9%. Incremental elevations in INR were independently associated with increasing risk for postoperative VTE [odds ratio (OR) 1.15, 95% confidence intervals 1.01-1.31], perioperative transfusion [OR 1.35 (1.28-1.43)], serious morbidity [OR 1.35 (1.28-1.43)], and mortality [OR 1.76 (1.56-1.98)].

CONCLUSION

Elevation in preoperative INR was counter-intuitively associated with increased risk of both VTE and perioperative transfusion following hepatectomy. The role of perioperative thromboprophylaxis warrants further investigation to determine optimal care in patients with elevated preoperative INR.

Development and validation of a risk calculator for post-discharge venous thromboembolism following hepatectomy for malignancy

BACKGROUND

Post-discharge venous thromboembolism (VTE) chemoprophylaxis decreases VTEs following cancer surgery, however identifying high-risk patients remains difficult. Our objectives were to (1) identify factors available at hospital discharge associated with post-discharge VTE following hepatectomy for malignancy and (2) develop and validate a post-discharge VTE risk calculator to evaluate patient-specific risk.

METHODS

Patients who underwent hepatectomy for malignancy from 2014 to 2017 were identified from the ACS NSQIP hepatectomy procedure targeted module. Multivariable logistic regression identified factors associated with post-discharge VTE. A post-discharge VTE risk calculator was constructed, and predicted probabilities of post-discharge VTE were calculated.

RESULTS

Among 11 172 patients, 95 (0.9%) developed post-discharge VTE. Post-discharge VTE was associated with obese BMI (OR 2.29 vs. normal BMI [95%CI 1.31-3.99]), right hepatectomy/trisegmentectomy (OR 1.63 vs. partial/wedge [95%CI 1.04-2.57]), and several inpatient postoperative complications: renal insufficiency (OR 5.29 [95%CI 1.99-14.07]), transfusion (OR 1.77 [95%CI 1.12-2.80]), non-operative procedural intervention (OR 2.97 [95%CI 1.81-4.86]), and post-hepatectomy liver failure (OR 2.22 [95%CI 1.21-4.08]). Post-discharge VTE risk ranged from 0.3% to 30.2%. Twenty iterations of 10-fold cross validation identified internal validity.

CONCLUSIONS

Risk factors from all phases of care, including inpatient complications, are associated with post-discharge VTE following hepatectomy. Identifying high-risk patients may allow for personalized risk-based post-discharge chemoprophylaxis prescribing.

Posthospital discharge venous thromboembolism prophylaxis among colorectal and hepatobiliary surgeons: A practice survey

BACKGROUND

Recent practice guidelines recommend venous thromboembolism prophylaxis for 28 days after cancer surgery. We sought to characterize and compare awareness, agreement, adoption, and adherence to these guidelines among surgeons.

METHODS

We electronically surveyed Canadian hepatobiliary surgeons registered with the Canadian Hepatopancreatobiliary Association, general and colorectal surgeons registered with the College of Physicians and Surgeons of Ontario and the Canadian Society of Colorectal Surgeons who provide colorectal cancer care with a pilot-tested questionnaire. Attitudes to relevant guideline recommendations and perceived barriers to postdischarge venous thromboembolism prophylaxis were assessed on a 5-point Likert scale.

RESULTS

There were 128 responses (response rate 60%, 128 of 213), including 60 general/colorectal and 68 hepatobiliary surgeons. Most surgeons were aware (122 of 128, 95%), agreed (101 of 122, 83%), adopted (78 of 101, 77%), and adhered (74 of 78, 95%) with guidelines. Preexisting venous thromboembolism-prophylaxis hospital programs, hepatobiliary surgeons, and geographical region were associated with increased likelihood of adherence. Among respondents that did not agree, insufficient evidence (median Likert: 4, interquartile range 3-5) and low incidence of venous thromboembolism (median Likert: 4, interquartile range 3-4) were cited as the strongest barriers. Surgeons who agreed but did not adopt these programs reported that the most significant barriers were "drug cost" (median Likert: 4, interquartile range 3-4) and "subcutaneous injections" (median Likert: 4, interquartile range 3-4). Surgeons that adhered additionally reported "logistical challenges of prescribing" as the greatest implementation barrier.

CONCLUSION

Surgeons who remain apprehensive about postdischarge venous thromboembolism prophylaxis cite poor evidence and cost of the medication as the major barriers. Adherence was higher among hepatobiliary surgeons and at hospitals with existing venous thromboembolism-prophylaxis programs.

Utility of viscoelastic coagulation testing in liver surgery: a systematic review

BACKGROUND

The objective of the current study was to summarize and evaluate all published evidence regarding viscoelastic testing in the field of liver surgery.

METHODS

A systematic search of the literature was performed using Medline/PubMed, Scopus, Cochrane Library Central, Google Scholar, and clinicaltrials.gov databases. The following keywords were used:"Thromboelastography", "Thromboelastometry", "Viscoelastic tests OR testing", "Sonoclot Devices", "Point-of-care tests OR testing", "Coagulation OR Haemostasis OR Hemostasis", "Liver OR Hepatic Surgery", "Cirrhosis."

RESULTS

A total of 12 studies analyzing 348 patients who underwent viscoelastic testing of coagulation during liver surgery for benign or malignant diseases were included; 7 (58.3%) studies reported on the use of thromboelastography (TEG), and 5 (41.7%) reported on rotational thromboelastometry (ROTEM). Viscoelastic testing (TEG and ROTEM) identified normo-, hyper- and hypo-coagulable status in 77% (n = 268/348), 18.4% (n = 64/348), and 4.6% (n = 16/348) of patients, respectively. In contrast, conventional coagulation tests indicated normo-coagulability in 111 patients (34.2% out of 325) and hypo-coagulability in 214 (65.8% out of 325) patients following liver resection. No patient (0% out of 291) experienced postoperative hemorrhage, whereas 5.8% (n = 17/291) experienced postoperative thromboembolic events.

CONCLUSIONS

Global viscoelastic testing may be a reasonable adjunct to conventional coagulation testing to provide a more robust assessment of the coagulation status of patients undergoing liver surgery.

Efficacy of pro- and anticoagulant strategies in plasma of patients undergoing hepatobiliary surgery

BACKGROUND

In vitro efficacy of pro- and antihemostatic drugs is profoundly different in patients with compensated cirrhosis and in those who have cirrhosis and are critically ill.

OBJECTIVES

Here we assessed the efficacy of pro- and anticoagulant drugs in plasma of patients undergoing hepato-pancreato-biliary (HPB) surgery, which is associated with unique hemostatic changes.

METHODS

We performed in vitro analyses on blood samples of 60 patients undergoing HPB surgery and liver transplantation: 20 orthotopic liver transplantations, 20 partial hepatectomies, and 20 pylorus-preserving pancreaticoduodenectomies. We performed thrombin generation experiments before and after in vitro addition of fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), recombinant factor VIIa (rFVIIa), low molecular weight heparin (LMWH), unfractionated heparin, dabigatran, and rivaroxaban.

RESULTS

We showed that patients undergoing HPB surgery are in a hypercoagulable state by thrombin generation testing. FFP and rFVIIa had minimal effects on thrombin generation, whereas PCC had a more pronounced procoagulant effect in patients compared with controls. Dabigatran showed a more pronounced anticoagulant effect in patients compared with controls, whereas rivaroxaban and LMWH had a decreased anticoagulant effect in patients.

CONCLUSION

We demonstrate profoundly altered in vitro efficacy of commonly used anticoagulants, in patients undergoing HPB surgery compared with healthy controls, which may have implications for anticoagulant dosing in the early postoperative period. In the correction of perioperative bleeding complications, PCCs appear much more potent than FFP or rFVIIa, and PCCs may require conservative dosing and caution in use in patients undergoing HPB surgery.

Anticoagulation status post radiofrequency ablation in a patient with hepatocellular carcinoma and delayed bleeding event

Restarting anticoagulation is a tricky component of patient care. This is a case of a 65-year-old female presenting with hepatocellular carcinoma. A nonocclusive thrombus in the main portal vein was also identified. Six days postradiofrequency ablation (RFA), the patient's hemoglobin dropped to critical values and noncontrast computed tomography of the abdomen/pelvis revealed high density free fluid consistent with a bleed. The patient was medically managed and accepted for transfer to another hospital for IR-guided TIPS procedure. Patient recovered without any other complications. In conclusion, VTE prophylaxis be routinely initiated immediately following hepatectomy in hemodynamically stable patients without signs of active bleeding and should bleeding occur halt source then restart anticoagulation immediately.

Coagulation in liver surgery: an observational haemostatic profile and thromboelastography study

BACKGROUND

International normalized ratio (INR) is used as a marker of the haemostatic status following liver resection. However, the impact of liver resection on haemostasis is complex and beyond what can be measured by INR. This study aimed to prospectively assess haemostatic profile following liver resection and determine if INR measurement can safely guide post-operative thromboprophylaxis.

METHODS

In this prospective cohort study, patients undergoing liver resection had coagulation parameters (International normalised ratio (INR), prothrombin time (PT), activated partial thromboplastin time, fibrinogen, d-dimer, von Willebrand factor antigen, procoagulant activity of phospholipids and clotting factors II, VII, VIIIc, IX and X) and thromboelastogram parameters assessed perioperatively. Clinical follow-up assessed for thromboembolism and haemorrhage.

RESULTS

In the 41 patients included, INR was significantly (P < 0.0001) elevated post-operatively, and INR >1.5 was observed in seven of 41 (17.1%) on post-operative day 1 and one of 41 (2.4%) patients on post-operative day 3, respectively. Factor VII levels showed transient reduction but other factors, especially factors II and X, remained within normal range following liver resection. Thromboelastogram parameters remained normal or supranormal for all patients at all time points. One incident of post-hepatectomy haemorrhage occurred, despite a normal coagulation profile. Two patients suffered late pulmonary embolic episodes.

CONCLUSION

Post liver resection haemostasis is complex and poorly reflected by INR, which should not guide initiation of chemical thromboprophylaxis in the immediate post-operative period.

Minimally Invasive Surgery is Associated with an Increased Risk of Postoperative Venous Thromboembolism After Distal Pancreatectomy

BACKGROUND

Venous thromboembolism (VTE) is a major cause of morbidity and mortality following distal pancreatectomy (DP). However, the influence of operative technique on VTE risk after DP is unknown.

OBJECTIVE

The purpose of this study was to examine the association between the MIS technique versus the open technique and the development of postoperative VTE after DP.

METHODS

Patients who underwent DP from 2014 to 2015 were identified in the American College of Surgeons National Surgical Quality Improvement Program pancreas-specific database. Multivariable logistic regression was then used to identify independent associations with the development of postoperative VTE after DP.

RESULTS

A total of 3558 patients underwent DP during this time period. Of these cases, 47.8% (n = 1702) were performed via the MIS approach. After adjusting for significant covariates, the MIS approach was independently associated with the development of any VTE (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.06-2.40; p = 0.025), as well as increasing the risk of developing a postdischarge VTE (OR 1.80, 95% CI 1.05-3.08; p = 0.033) when compared with the open approach. There was an association between VTE and the development of numerous postoperative complications, including pneumonia, unplanned intubation, need for prolonged mechanical ventilation, and cardiac arrest.

CONCLUSION

Compared with the open approach, the MIS approach is associated with higher rates of postoperative VTE in patients undergoing DP. The majority of these events are diagnosed after hospital discharge.

Dabigatran (Pradaxa) Is Safe for Extended Venous Thromboembolism Prophylaxis After Surgery for Pancreatic Cancer

BACKGROUND

The American College of Chest Physicians and American Hepato-Pancreato-Biliary Association recommend using low-molecular-weight heparin for 28 days postoperatively for venous thromboembolism prophylaxis after cancer surgery. Dabigatran is a once daily oral anticoagulant that is FDA approved for venous thromboembolism prophylaxis after orthopedic surgery, uses fixed dosing, and has an antidote.

METHODS

Patients undergoing surgery for malignant pancreatic tumors (neuroendocrine excluded) from January 2017 to January 2018 were converted to dabigatran 220 mg daily on discharge until postoperative day 28; patients with medical or insurance contraindications were converted to enoxaparin or another direct oral anticoagulant. The primary endpoint was bleeding complications through 90 days.

RESULTS

A total of 134 patients were considered for this study (median age 67 ± 10; 58.9% male). Eighty-seven (82.9%) patients received dabigatran and 18 (17.1%) received another form of anticoagulation. There were 19 (4.2%) patients not prescribed dabigatran due to medical or inpatient contraindications. Four patients experienced bleeding complications after discharge while on dabigatran. Two (2%) were major bleeds (Clavien-Dindo IV and V), and 2 (2%) were minor (Clavien-Dindo I). Patient compliance was excellent, with 93% of prescribed patients fully completing their prophylaxis. There were 2 patients that developed symptomatic deep vein thrombosis.

CONCLUSION

The use of a direct oral anticoagulant as extended venous thromboembolism prophylaxis after major gastrointestinal surgery has not been studied to date. These results show dabigatran to be a safe alternative to low-molecular-weight heparin for extended venous thromboembolism prophylaxis with regard to bleeding complications.

Enhanced recovery after surgery in liver resection: current concepts and controversies

Enhanced recovery after surgery (ERAS) attenuates the stress response to surgery in the perioperative period and hastens recovery. Liver resection is a complex surgical procedure where the enhanced recovery program has been shown to be safe and effective in terms of postoperative outcomes. ERAS programs have been shown to be associated with lower morbidity, shortened postoperative stay, and reduced cost with no difference in mortality and readmission rates. However, there are challenges that are unique to hepatic resection such as safety after epidural catheterization and postoperative coagulopathy, intraoperative fluids and postoperative organ dysfunction, need for low central venous pressure to reduce blood loss, and non-lactate containing intravenous fluids. This narrative review briefly discusses these concerns and controversies and suggests revisiting some of the strong recommendations made by the ERAS society in light of the recent evidence.

Enhanced recovery in liver surgery

Enhanced recovery in liver surgery has been shown to improve outcomes including patient-reported outcomes, length of stay, return to intended oncology therapy, and cost. The goal of this chapter will be to review the elements of a modern enhanced recovery pathway that is utilized across the entire episode of care in liver surgery.

Intraoperative cell salvage with autologous transfusion in elective right or repeat hepatectomy: a propensity-score-matched case-control analysis

BACKGROUND

Liver resection may be associated with substantial blood loss, and cell saver use has been recommended for patients at high risk. We performed a study to compare the allogenic erythrocyte transfusion rate after liver resection between patients who had intraoperative cell salvage with a cell saver device versus patients who did not. Our hypothesis was that cell salvage with autologous transfusion would reduce the allogenic blood transfusion rate.

METHODS

Cell salvage was used selectively in patients at high risk for intraoperative blood loss based on preoperatively known predictors: right and repeat hepatectomy. Patients who underwent elective right or repeat hepatectomy between Nov. 9, 2007, and Jan. 27, 2016 were considered for the study. Data were retrieved from a liver resection database and were analyzed retrospectively. Patients with cell saver use (since January 2013) constituted the experimental group, and those without cell salvage (2007-2012), the control group. To reduce selection bias, we matched propensity scores. The primary outcome was the allogenic blood transfusion rate within 90 days postoperatively. Secondary outcomes were the number of transfused erythrocyte units, and rates of overall and infectious complications.

RESULTS

Ninety-six patients were included in the study, 41 in the cell saver group and 55 in the control group. Of the 96, 64 (67%) could be matched, 32 in either group. The 2 groups were balanced for demographic and clinical variables. The allogenic blood transfusion rate was 28% (95% confidence interval [CI] 12.5%-43.7%) in the cell saver group versus 72% (95% CI 56.3%-87.5%) in the control group (p < 0.001). The overall and infectious complication rates were not significantly different between the 2 groups.

CONCLUSION

Intraoperative cell salvage with autologous transfusion in elective right or repeat hepatectomy reduced the allogenic blood transfusion rate.

Identification of patients at high risk for post-discharge venous thromboembolism after hepato-pancreato-biliary surgery: which patients benefit from extended thromboprophylaxis?

BACKGROUND

The objective of the current study was to define risk factors associated with the 30-day post-operative risk of VTE after HPB surgery and create a model to identify patients at highest risk of post-discharge VTE.

METHODS

Patients who underwent hepatectomy or pancreatectomy in the ACS-NSQIP Participant Use Files 2011-2015 were identified. Logistic regression modeling was used; a model to predict post-discharge VTE was developed. Model discrimination was tested using area under the curve (AUC).

RESULTS

Among 48,860 patients, the overall 30-day incidence of VTE after hepatectomy and pancreatectomy was 3.2% (n = 1580) with 1.1% (n = 543) of VTE events occurring after discharge. Patients who developed post-discharge VTE were more likely to be white, had a higher median BMI, have undergone pancreatic surgery, had longer median operative times, and to have had a transfusion. A weighted prediction model demonstrated good calibration and fair discrimination (AUC = 0.63). A score of ≥-4.50 had maximum sensitivity and specificity, resulting in 44% of patients being treating with prophylaxis for an overall VTE risk of 1.1%.

CONCLUSIONS

Utilizing independent factors associated with post-discharge VTE, a prediction model was able to stratify patients according to risk of VTE and may help identify patients who are most likely to benefit from pharmacoprophylaxis.

Use of aspirin and bleeding-related complications after hepatic resection

Background

The operative risk of hepatectomy under antiplatelet therapy is unknown. This study sought to assess the outcomes of elective hepatectomy performed with or without aspirin continuation in a well balanced matched cohort.

Methods

Data were retrieved from a multicentre prospective observational study. Aspirin and control groups were compared by non-standardized methods and by propensity score (PS) matching analysis. The main outcome was severe (Dindo–Clavien grade IIIa or more) haemorrhage. Other outcomes analysed were intraoperative transfusion, overall haemorrhage, major morbidity, comprehensive complication index (CCI) score, thromboembolic complications, ischaemic complications and mortality.

Results

Before matching, there were 118 patients in the aspirin group and 1685 in the control group. ASA fitness grade, cardiovascular disease, previous history of angina pectoris, angioplasty, diabetes, use of vitamin K antagonists, cirrhosis and type of hepatectomy were significantly different between the groups. After PS matching, 108 patients were included in each group. There were no statistically significant differences between the aspirin and control groups in severe haemorrhage (6·5 versus 5·6 per cent respectively; odds ratio (OR) 1·18, 95 per cent c.i. 0·38 to 3·62), intraoperative transfusion (23·4 versus 23·7 per cent; OR 0·98, 0·51 to 1·87), overall haemorrhage (10·2 versus 12·0 per cent; OR 0·83, 0·35 to 1·94), CCI score (24 versus 28; P = 0·520), major complications (23·1 versus 13·9 per cent; OR 1·82, 0·92 to 3·79) and 90-day mortality (5·6 versus 4·6 per cent; OR 1·21, 0·36 to 4·09).

Conclusion

This observational study suggested that aspirin continuation is not associated with a higher rate of bleeding-related complications after elective hepatic surgery.

Extended pharmacologic thromboprophylaxis in oncologic liver surgery is safe and effective

Essentials The risk for venous thromboembolism after liver surgery remains high in the modern era. We evaluated the safety/efficacy of extended anticoagulation in liver surgery. This protocol reports zero venous thromboembolism events in 124 liver surgery patients. Extended anticoagulation after oncologic liver surgery is safe and effective.

SUMMARY

Background The incidence of venous thromboembolism (VTE) after liver surgery remains high. Objective To evaluate the safety and efficacy of extended pharmacologic thromboprophylaxis after liver surgery for the prevention of VTE. Patient/Methods From August 2013 to April 2015, 124 patients who underwent liver resection for malignancy were placed on an extended pharmacologic thromboprophylaxis protocol. Intraoperative VTE prophylaxis included thromboembolic deterrent hoses and sequential compression devices. Once hemostasis had been ensured following hepatectomy, daily anticoagulant VTE prophylaxis was initiated for the duration of hospitalization. After hospital discharge, the large majority of patients (114, 91.9%) continued to receive anticoagulant thromboprophylaxis (enoxaparin) to complete a total course of 14 days after minor/minimally invasive hepatectomy or 28 days after major hepatectomy or a history of VTE. Results The cohort included 39 (31.2%) major hepatectomies and 38 (31.5%) minor/minimally invasive approaches. The intraoperative, postoperative and overall transfusion rates were 5.6%, 8.1%, and 10.5%, respectively. Pharmacologic thromboprophylaxis was started on postoperative day (POD) 0 for 40 (32.3%) patients and on POD 1 for 84 (67.7%) patients. During 90 days of follow-up, no postoperative symptomatic deep vein thrombosis or pulmonary embolic events were diagnosed. Standard-protocol computed tomography scans of the chest, abdomen and pelvis that were obtained for 112 (90.3%) study patients showed no pulmonary emboli, or other thoracic, splanchnic or ileofemoral vein thromboses. Two (1.6%) patients had minor bleeding events that resolved after discontinuation of enoxaparin, requiring neither blood transfusion nor reoperation. The severe complication rate was 5.6%, with no 90-day mortalities. Conclusions These preliminary data suggest that extended pharmacologic thromboprophylaxis for liver surgery patients is safe and effective.

Coagulopathy Before and After Liver Transplantation: From the Hepatic to the Systemic Circulatory Systems

The hemostatic environment in patients with cirrhosis is a delicate balance between prohemostatic and antihemostatic factors. There is a lack of effective laboratory measures of the hemostatic system in patients with cirrhosis. Many are predisposed to pulmonary embolus, deep vein thrombosis, and portal vein thrombosis in the pretransplantation setting. This pretransplantation hypercoagulable milieu seems to extend for at least several months post-transplantation. Patients with nonalcoholic fatty liver disease, inherited thrombophilia, portal hypertension in the absence of cirrhosis, and hepatocellular carcinoma often require individualized approach to anticoagulation. Early reports suggest a potential role for low-molecular-weight heparins and direct-acting anticoagulants.

Efficacy and safety of pharmacological venous thromboembolism prophylaxis following liver resection: a systematic review and meta-analysis

BACKGROUND

Current guidelines recommend pharmacological prophylaxis for patients undergoing abdominal surgery for malignancy. Liver resection exposes patients to risk factors for venous thromboembolism, but there is a risk of bleeding. The aim of this study is to evaluate the evidence base supporting the use of pharmacological thromboprophylaxis in liver surgery.

METHODS

An electronic search was carried out for studies reporting the incidence of VTE following liver resection comparing patients receiving pharmacological prophylaxis with those who did not. The search resulted in 990 unique citations. Following the application of strict eligibility criteria 5 studies comprise the final study population.

RESULTS

Included studies report on 3675 patients undergoing liver resection between 1999 and 2013. 2256 patients received chemical thromboprophylaxis, 1412 had mechanical prophylaxis only and 7 received no prophylaxis. Meta-analysis revealed lower VTE rates in patients receiving chemical thromboprophylaxis (2.6%) compared to without prophylaxis (4.6%) (Dichotomous correlation test, odds ratio: 0.631 [95% Cl: 0.416-0.959], Fixed model, p = 0.030). Data regarding bleeding could not be pooled for meta-analysis, but chemical thromboprophylaxis was reported as safe in four studies.

CONCLUSION

This systematic review and meta-analysis of retrospective studies indicates that the use of perioperative chemical thromboprophylaxis reduces VTE incidence following liver surgery without an apparent increased risk of bleeding.

Thromboelastography demonstrates perioperative hypercoagulability in hepato-pancreato-biliary patients and supports routine administration of preoperative and early postoperative venous thromboembolism chemoprophylaxis

BACKGROUND

We hypothesized hepato-pancreato-biliary (HPB) surgery patients are more likely to be hypercoagulable than hypocoagulable, and that bleeding risks from VTE chemoprophylaxis are low. This study sought to use thromboelastography (TEG) to compare coagulation profiles with bleeding/thrombotic events in HPB patients receiving standardized perioperative chemoprophylaxis.

METHODS

Consecutive patients undergoing HPB resections by three surgeons at one institution (January 2014-December 2015) received preoperative and early postoperative VTE chemoprophylaxis and were evaluated with TEGs. Coagulation profiles were compared to bleeding/thrombotic events.

RESULTS

Of 87 total patients, 83 (95.4%) received preoperative chemoprophylaxis and 100% received it postoperatively. Median estimated blood loss was 190 ml. Only 2 (2.3%) patients received intraoperative transfusions. None required transfusions at 72-hours. Only 2 were transfused within 30 days. There was 1 (1.1%) 30-day VTE event. Of 83 preoperative TEGs, 29 (34.9%) were hypercoagulable and only 8 (9.6%) were hypocoagulable/fibrinolytic. Of 73 postoperative TEGs, 34 (46.6%) were hypercoagulable and just 8 (11.0%) were hypocoagulable/fibrinolytic. .

CONCLUSION

With routine perioperative chemoprophylaxis, both VTE and bleeding events were negligible. Perioperative TEG revealed a considerable proportion (46.6%) of HPB patients were hypercoagulable. HPB patients can receive standardized preoperative/early postoperative VTE chemoprophylaxis with effective results and minimal concern for perioperative hemorrhage.

Risk factors associated with venous thromboembolism in patients undergoing spine surgery

OBJECTIVE

Patients undergoing spinal surgery are at risk for developing venous thromboembolism (VTE). The authors sought to identify risk factors for VTE in these patients.

METHODS

The American College of Surgeons National Surgical Quality Improvement Project database for the years 2006–2010 was reviewed for patients who had undergone spinal surgery according to their primary Current Procedural Terminology code(s). Clinical factors were analyzed to identify associations with VTE.

RESULTS

Patients who underwent spinal surgery (n = 22,434) were identified. The rate of VTE in the cohort was 1.1% (pulmonary embolism 0.4%; deep vein thrombosis 0.8%). Multivariate binary logistic regression analysis revealed 13 factors associated with VTE. Preoperative factors included dependent functional status, paraplegia, quadriplegia, disseminated cancer, inpatient status, hypertension, history of transient ischemic attack, sepsis, and African American race. Operative factors included surgery duration > 4 hours, emergency presentation, and American Society of Anesthesiologists Class III–V, whereas postoperative sepsis was the only significant postoperative factor. A risk score was developed based on the number of factors present in each patient. Patients with a score of ≥ 7 had a 100-fold increased risk of developing VTE over patients with a score of 0. The receiver-operating-characteristic curve of the risk score generated an area under the curve of 0.756 (95% CI 0.726–0.787).

CONCLUSIONS

A risk score based on race, preoperative comorbidities, and operative characteristics of patients undergoing spinal surgery predicts the postoperative VTE rate. Many of these risks can be identified before surgery. Future protocols should focus on VTE prevention in patients who are predisposed to it.

Patient Adherence and Experience with Extended Use of Prophylactic Low-Molecular-Weight Heparin Following Pancreas and Liver Resection

BACKGROUND

Guidelines recommend 28 days venous thromboembolism (VTE) prophylaxis with low-molecular-weight heparin (LMWH) following major abdominal surgery for cancer. Overall adherence with these recommendations is poor, but little is known about feasibility and tolerability from a patient perspective.

METHODS

An institution-wide policy for routine administration of 28 days of post-operative LMWH following major hepatic or pancreatic resection for cancer was implemented in April 2013. Patients having surgery from July 2013 to June 2015 were approached to participate in an interview examining adherence and experience with extended duration LMWH.

RESULTS

There were 100 patients included, with 81.4 % reporting perfect adherence with the regimen. The most frequent reasons for non-adherence were that a healthcare provider stopped the regimen or because of poor experience with injections. Most patients were able to correctly recall the reason for being prescribed LMWH (82.6 %), and 78.4 % of patients performed all injections themselves. Over half the patients (55.7 %) did not find the injections bothersome.

CONCLUSION

Patients reported high adherence and a manageable experience with post-operative extended-duration LMWH in an ambulatory setting following liver or pancreas resection. These findings suggest that patient adherence is not a major contributor to poor compliance with VTE prophylaxis guidelines.

Borderline operability in hepatectomy patients is associated with higher rates of failure to rescue after severe complications

BACKGROUND/OBJECTIVE

To understand the influence of age and comorbidities, this study analyzed the incidence and risk factors for post-hepatectomy morbidity/mortality in patients with "borderline" (BL) operability, defined by the preoperative factors: age ≥75 years, dependent function, lung disease, ascites/varices, myocardial infarction, stroke, steroids, weight loss >10%, and/or sepsis.

METHODS

All elective hepatectomies were identified in the 2005-2013 ACS-NSQIP database. Predictors of 30-day morbidity/mortality in BL patients were analyzed.

RESULTS

A 3,574/15,920 (22.4%) patients met BL criteria. Despite non-BL and BL patients undergoing similar magnitude hepatectomies (P > 0.4), BL patients had higher severe complication (SC, 23.3% vs. 15.3%) and mortality rates (3.7% vs. 1.2%, P < 0.001). BL patients with any SC experienced a 14.1% mortality rate (vs. 7.3%, non-BL, P < 0.001). Independent risk factors for SC in BL patients included American Society of Anesthesiologists (ASA) score >3 (odds ratio, OR - 1.29), smoking (OR - 1.41), albumin <3.5 g/dl (OR - 1.36), bilirubin >1 (OR - 2.21), operative time >240 min (OR - 1.58), additional colorectal procedure (OR - 1.78), and concurrent procedure (OR - 1.73, all P < 0.05). Independent predictors of mortality included disseminated cancer (OR - 0.44), albumin <3.5 g/dl (OR - 1.94), thrombocytopenia (OR - 1.95), and extended/right hepatectomy (OR - 2.81, all P < 0.01).

CONCLUSIONS

Hepatectomy patients meeting BL criteria have an overall post-hepatectomy mortality rate that is triple that of non-BL patients. With less clinical reserve, BL patients who suffer SC are at greater risk of post-hepatectomy death. J. Surg. Oncol. 2017;115:337-343. © 2016 Wiley Periodicals, Inc.

Differences in Perioperative Outcomes Between Right and Left Hepatic Lobectomy

The safety of hepatic resection is well documented, but outcome studies comparing right and left hepatic lobectomy are sparse, especially in the context of malignancy. This study analyzes the differences in outcomes between right and left hepatic lobectomy in patients with malignant diagnoses. All patients undergoing right and left hepatic lobectomies for malignancy were extracted from the National Surgical Quality Improvement Program (NSQIP) database (2005-2010). The data was analyzed to determine differences in perioperative mortality and morbidity between the two groups. A total of 1680 patients who underwent right or left hepatic lobectomy for malignant diagnoses were identified. Patients undergoing right hepatic lobectomy had a four-fold increase in perioperative mortality, compared to left lobectomy (p < 0.0001). Mortality in right lobectomy patients increased incrementally with age, with a 12-fold increase in patients > 81 years of age. Patients undergoing right lobectomy also experienced a statistically significant increase in morbidity involving several systems (infectious, pulmonary, cardiac and renal). The results of our study demonstrate that patients undergoing right hepatic lobectomy for malignancy experience a significantly higher incidence of mortality and multi-system morbidity when compared to left lobectomy. This information will be crucial for pre-operative risk-stratification of patients undergoing hepatic resection for malignancy.

Alterations in coagulation following major liver resection

The international normalised ratio is frequently raised in patients who have undergone major liver resection, and is assumed to represent a potential bleeding risk. However, these patients have an increased risk of venous thromboembolic events, despite conventional coagulation tests indicating hypocoagulability. This prospective, observational study of patients undergoing major hepatic resection analysed the serial changes in coagulation in the early postoperative period. Thrombin generation parameters and viscoelastic tests of coagulation (thromboelastometry) remained within normal ranges throughout the study period. Levels of the procoagulant factors II, V, VII and X initially fell, but V and X returned to or exceeded normal range by postoperative day five. Levels of factor VIII and Von Willebrand factor were significantly elevated from postoperative day one (p < 0.01). Levels of the anticoagulants, protein C and antithrombin remained significantly depressed on postoperative day five (p = 0.01). Overall, the imbalance between pro- and anticoagulant factors suggested a prothrombotic environment in the early postoperative period.

Balance between von Willebrand factor and ADAMTS13 following major partial hepatectomy

BACKGROUND

Conventional coagulation tests are frequently prolonged after liver surgery, suggesting a postoperative bleeding tendency. At the same time, thrombotic complications following partial hepatectomy (PH) are not uncommon. Little is known about changes in the platelet adhesive protein von Willebrand factor (VWF) and its cleaving protease a disintegrin and metalloprotease with a thrombospondin type 1 motif, member 13 (ADAMTS13) following a PH.

METHODS

Plasma samples were collected before and after PH and pylorus-preserving pancreaticoduodenectomy (PPPD), and from 24 healthy individuals. Plasma levels of VWF and ADAMTS13, VWF activity and VWF-dependent platelet adhesion were measured, and compared between the groups.

RESULTS

Median (i.q.r.) VWF levels increased more after PH (17 patients) than following PPPD (10), reaching the highest level on postoperative day (POD) 3 (570 (473-656) versus 354 (305-476) per cent respectively; P = 0·009). VWF levels remained raised on POD 30. A decrease in median (i.q.r.) ADAMTS13 activity was observed for both patient groups, reaching the lowest level on POD 7 (24 (16-32) versus 38 (23-66) per cent for PH and PPPD respectively; P = 0·049), and levels remained significantly reduced at POD 30. VWF activity was significantly higher on day 7 following PH compared with PPPD (median (i.q.r.) 517 (440-742) versus 385 (322-484) per cent respectively; P = 0·009), and remained increased at POD 30. VWF-dependent platelet adhesion under conditions of flow was increased until POD 30 in patients after PH and PPPD, but was more pronounced in the PH group.

CONCLUSION

There are changes in the balance between VWF and ADAMTS13 levels and activity in patients after both PH and PPPD. Changes in the VWF-ADAMTS13 axis were more pronounced and of longer duration after PH than following PPPD.

Preoperative selection of patients with colorectal cancer liver metastasis for hepatic resection

Surgical resection of colorectal liver metastases (CRLM) has a well-documented improvement in survival. To benefit from this intervention, proper selection of patients who would be adequate surgical candidates becomes vital. A combination of imaging techniques may be utilized in the detection of the lesions. The criteria for resection are continuously evolving; currently, the requirements that need be met to undergo resection of CRLM are: the anticipation of attaining a negative margin (R0 resection), whilst maintaining an adequate functioning future liver remnant. The timing of hepatectomy in regards to resection of the primary remains controversial; before, after, or simultaneously. This depends mainly on the tumor burden and symptoms from the primary tumor. The role of chemotherapy differs according to the resectability of the liver lesion(s); no evidence of improved survival was shown in patients with resectable disease who received preoperative chemotherapy. Presence of extrahepatic disease in itself is no longer considered a reason to preclude patients from resection of their CRLM, providing limited extra-hepatic disease, although this currently is an area of active investigations. In conclusion, we review the indications, the adequate selection of patients and perioperative factors to be considered for resection of colorectal liver metastasis.