High incidence of thrombosis of the portal venous system after laparoscopic splenectomy: a prospective study with contrast-enhanced CT scan

Portal vein velocity predicts portal vein system thrombosis after splenectomy with esophagogastric devascularization

BACKGROUND

Portal vein system thrombosis (PVST) is a potentially fatal complication after splenectomy with esophagogastric devascularization (SED) in cirrhotic patients with portal hypertension. However, the impact of portal vein velocity (PVV) on PVST after SED remains unclear. Therefore, this study aims to explore this issue.

METHODS

Consecutive cirrhotic patients with portal hypertension who underwent SED at Tongji Hospital between January 2010 and June 2022 were enrolled. The patients were divided into two groups based on the presence or absence of PVST, which was assessed using ultrasound or computed tomography after the operation. PVV was measured by duplex Doppler ultrasound within one week before surgery. The independent risk factors for PVST were analyzed using univariate and multivariate logistic regression analysis. A nomogram based on these variables was developed and internally validated using 1000 bootstrap resamples.

RESULTS

A total of 562 cirrhotic patients with portal hypertension who underwent SED were included, and PVST occurred in 185 patients (32.9%). Multivariate logistic regression analysis showed that PVV was the strongest independent risk factor for PVST. The incidence of PVST was significantly higher in patients with PVV ≤ 16.5 cm/s than in those with PVV > 16.5 cm/s (76.2% vs. 8.5%, p < 0.0001). The PVV-based nomogram was internally validated and showed good performance (optimism-corrected c-statistic = 0.907). Decision curve and clinical impact curve analyses indicated that the nomogram provided a high clinical benefit.

CONCLUSION

A nomogram based on PVV provided an excellent preoperative prediction of PVST after splenectomy with esophagogastric devascularization.

Risk factors of portal vein system thrombosis after splenectomy: a meta-analysis

BACKGROUND

The primary aim of the present study was to explore risk factors for portal vein system thrombosis following splenectomy.

METHODS

A systematic search of PubMed, Embase and Cochrane libraries was conducted to identify original studies that fulfilled the inclusion criteria. Raw data on potential risk factors for portal vein system thrombosis after splenectomy were extracted for meta-analysis. Subsequently, a sensitivity analysis was conducted to verify the stability of the results.

RESULTS

Eighteen studies with 626 thrombosis events from 1807 splenectomy met the inclusion criteria. Larger spleen volume (SMD 0.44, P = 0.000), broader splenic vein diameter (WMD 2.30, P = 0.000), broader portal vein diameter (WMD 2.08, P = 0.000), a lower velocity of portal blood flow (WMD -0.91, P = 0.001), decreased platelet count (WMD -5.14, P = 0.007), decreased white blood cell (WMD -0.40, P = 0.027), decreased haemoglobin (WMD -9.14, P = 0.002), ascites (OR 1.81, P = 0.003) and bleeding history before surgery (OR 1.88, P = 0.002) were identified to be factors that exacerbated the risk of portal vein system thrombosis after splenectomy. Sex, age, preoperative prothrombin time, postoperative platelet count, postoperative D-dimer, operation time and intraoperative blood loss, did not increase the risk of thrombosis.

CONCLUSION

Larger spleen volume, broader splenic vein diameter, broader portal vein diameter, a lower velocity of portal blood flow, ascites, bleeding history before surgery, decreased platelet count, white blood cell and haemoglobin may increase the risk of portal vein system thrombosis.

Porto-spleno-mesenteric venous thrombosis after elective splenectomy: a retrospective cohort study

Background

Elective splenectomy is the main treatment for a wide range of haematological diseases. Porto-spleno-mesenteric venous thrombosis represents one of the most severe complications of this procedure. The aim of this study was to evaluate risk factors associated with development of porto-spleno-mesenteric venous thrombosis after elective splenectomy.

Methods

All cases of elective splenectomy carried out from April 1st 2017 to January 31st 2023 were included in this single centre retrospective cohort study. Patients' demographics and perioperative data were analysed and correlated with the incidence of postoperative thrombosis. All patients underwent postoperative doppler ultrasound screening for thrombosis. Analysis was performed using SPSS 28, with p-value < 0.05 considered significant.

Results

Twenty-two patients (10 women, 12 men) underwent splenectomy during the study period. Indications were: immune thrombocytopenia (n: 6), myeloproliferative disorder (n: 6), hereditary spherocytosis (n: 4), thalassemia (n: 1), lymphoma (n: 1), leukaemia (n: 1), other malignancies (n: 3). Six patients developed porto-spleno-mesenteric venous thrombosis and only 2 of them were symptomatic. Patients were treated with anticoagulation therapy with complete resolution. Analysis identified three main factors associated with thrombosis: spleen diameter (p = 0.03), myeloproliferative disorder (p = 0.02), intraoperative platelet transfusion (p = 0.002) and intraoperative red blood cells transfusion (p = 0.009).

Conclusion

Standardized postoperative screening allows prompt diagnosis and treatment of porto-spleno-mesenteric venous thrombosis even in asymptomatic cases. Patient with splenomegaly and affected by myeloproliferative disorder have a greater risk to develop this complication.

Early prevention and risk factors analysis of portal vein system thrombosis after laparoscopic splenectomy and pericardial devascularization

BACKGROUND

Portal vein system thrombosis (PVST) is a common postoperative complication brought by laparoscopic splenectomy and pericardial disconnection (LSD) among patients who suffered from portal hypertension and hypersplenism. This research lies mainly in probing into the risk factors of PVST and evaluating the effects of warfarin on PVST prevention.

MATERIALS AND METHODS

We took 131 individuals who have carried out LSD from January 2015 to January 2021. Patients were divided into warfarin group (n = 68) and aspirin group (n = 63). Meanwhile, thrombosis factors were analyzed in PVST arm (n = 48) and non-PVST arm (n = 83).

RESULTS

We analyzed the early postoperative anticoagulation effect, 20 patients (29.4%) in the warfarin group developed PVST, and 28 patients (44.4%) in the aspirin group. The chance to PVST during the first year after operation was lower in the warfarin group than in the aspirin group (F = 13.43, P = 0.006). Risk factors for PVST were analyzed, and diabetes, the diameter of the portal vein and splenic vein, and the velocity of portal blood flow were statistically significant between the PVST arm and non-PVST arm (P <  < 0.05). Multiple logistic regression analyses have shown that diabetes, portal vein diameter, splenic vein diameter, and the velocity of portal blood flow were the risk factors of PVST.

CONCLUSIONS

The portal vein diameter, splenic vein diameter, portal vein flow velocity, and diabetes are risk factors for the PVST after LSD. The prophylactic use of warfarin anticoagulation markedly decreases the probability of occurrence of the PVST in patients with portal hypertension after LSD compared to aspirin.

Prophylactic Splenectomy and Hyposplenism in Spaceflight

BACKGROUND: There is debate whether astronauts traveling to space should undergo a prophylactic splenectomy prior to long duration spaceflight. Risks to the spleen during flight include radiation and trauma. However, splenectomy also carries significant risks.METHODS: Systematic review of data published over the past 5 decades regarding risks associated with splenectomies and risks associated with irradiation to the spleen from long duration spaceflight were analyzed. A total of 41 articles were reviewed.RESULTS: Acute risks of splenectomy include intraoperative mortality rate (from hemorrhage) of 3-5%, mortality rate from postoperative complications of 6%, thromboembolic event rate of 10%, and portal vein thrombosis rate of 5-37%. Delayed risks of splenectomy include overwhelming postsplenectomy infection (OPSI) at 0.5% at 5 yr post splenectomy, mortality rate as high as 60% for pneumococcal infections, and development of malignancy with relative risk of 1.53. The risk of hematologic malignancy increases significantly when individuals reach 40 Gy of exposure, much higher than the 0.6 Gy of radiation experienced from a 12-mo round trip to Mars. Lower doses of radiation increase the risk of hyposplenism more so than hematologic malignancy.CONCLUSION:For protection against hematologic malignancy, the benefits of prophylactic splenectomy do not outweigh the risks. However, there is a possible risk of hyposplenism from long duration spaceflight. It would be beneficial to prophylactically provide vaccines against encapsulated organisms for long duration spaceflight to mitigate the risk of hyposplenism.Siu M, Levin D, Christiansen R, Kelly E, Alouidor R, Kamine TH. Prophylactic splenectomy and hyposplenism in spaceflight. Aerosp Med Hum Perform. 2022; 93(12):877-881.

Machine learning predicts portal vein thrombosis after splenectomy in patients with portal hypertension: Comparative analysis of three practical models

BACKGROUND

For patients with portal hypertension (PH), portal vein thrombosis (PVT) is a fatal complication after splenectomy. Postoperative platelet elevation is considered the foremost reason for PVT. However, the value of postoperative platelet elevation rate (PPER) in predicting PVT has never been studied.

AIM

To investigate the predictive value of PPER for PVT and establish PPER-based prediction models to early identify individuals at high risk of PVT after splenectomy.

METHODS

We retrospectively reviewed 483 patients with PH related to hepatitis B virus who underwent splenectomy between July 2011 and September 2018, and they were randomized into either a training (n = 338) or a validation (n = 145) cohort. The generalized linear (GL) method, least absolute shrinkage and selection operator (LASSO), and random forest (RF) were used to construct models. The receiver operating characteristic curves (ROC), calibration curve, decision curve analysis (DCA), and clinical impact curve (CIC) were used to evaluate the robustness and clinical practicability of the GL model (GLM), LASSO model (LSM), and RF model (RFM).

RESULTS

Multivariate analysis exhibited that the first and third days for PPER (PPER1, PPER3) were strongly associated with PVT [odds ratio (OR): 1.78, 95% confidence interval (CI): 1.24-2.62, P = 0.002; OR: 1.43, 95%CI: 1.16-1.77, P < 0.001, respectively]. The areas under the ROC curves of the GLM, LSM, and RFM in the training cohort were 0.83 (95%CI: 0.79-0.88), 0.84 (95%CI: 0.79-0.88), and 0.84 (95%CI: 0.79-0.88), respectively; and were 0.77 (95%CI: 0.69-0.85), 0.83 (95%CI: 0.76-0.90), and 0.78 (95%CI: 0.70-0.85) in the validation cohort, respectively. The calibration curves showed satisfactory agreement between prediction by models and actual observation. DCA and CIC indicated that all models conferred high clinical net benefits.

CONCLUSION

PPER1 and PPER3 are effective indicators for postoperative prediction of PVT. We have successfully developed PPER-based practical models to accurately predict PVT, which would conveniently help clinicians rapidly differentiate individuals at high risk of PVT, and thus guide the adoption of timely interventions.

Predicting the risk of postsplenectomy thrombosis in patients with portal hypertension using computational hemodynamics models: A proof-of-concept study

BACKGROUND

The high incidence of thrombosis in the portal venous system following splenectomy (a frequently adopted surgery for treating portal hypertension in patients with splenomegaly and hypersplenism) is a critical clinical issue. The aim of this study was to address whether quantification of postsplenectomy hemodynamics has potential value for assessing the risk of postsplenectomy thrombosis.

METHODS

Computational models were constructed for three portal hypertensive patients treated with splenectomy based on their preoperative clinical data to quantify hemodynamics in the portal venous system before and after splenectomy, respectively. Each patient was followed up for three or five months after surgery and examined with CT to screen potential thrombosis.

FINDINGS

The area ratio of wall regions exposed to low wall shear stress was small before splenectomy in all patients, which increased markedly after splenectomy and exhibited enlarged inter-patient differences. The largest area ratio of low wall shear stress and most severe flow stagnation after splenectomy were predicted for the patient suffering from postsplenectomy thrombosis, with the wall regions exposed to low wall shear stress corresponding well with the CT-detected distribution of thrombus. Further analyses revealed that postoperative hemodynamic characteristics were considerably influenced by the anatomorphological features of the portal venous system.

INTERPRETATION

Postoperative hemodynamic conditions in the portal venous system are highly patient-specific and have a potential link to postsplenectomy thrombosis, which indicates that patient-specific hemodynamic studies may serve as a complement to routine clinical assessments for refining risk stratification and postoperative patient management.

Portal vein thrombosis in a noncirrhotic patient after hemihepatectomy: A case report and review of literature

BACKGROUND

Portal vein thrombosis (PVT) is a condition caused by hemodynamic disorders. It may be noted in the portal vein system when there is an inflammatory stimulus in the abdominal cavity. However, PVT is rarely reported after hepatectomy. At present, related guidelines and major expert opinions tend to consider vitamin K antagonists or low-molecular weight heparin (LMWH) as the standard treatment. But based on research, direct oral anticoagulants may be more effective and safe for noncirrhotic PVT and are also beneficial by reducing the recurrence rate of PVT.

CASE SUMMARY

A 51-year-old woman without any history of disease felt discomfort in her right upper abdomen for 20 d, with worsening for 7 d. Contrast-enhanced computed tomography (CECT) of the upper abdomen showed right liver intrahepatic cholangiocarcinoma with multiple intrahepatic metastases but not to the left liver. Therefore, she underwent right hepatic and caudate lobectomy. One week after surgery, the patient underwent a CECT scan, due to nausea, vomiting, and abdominal distension. Thrombosis in the left branch and main trunk of the portal vein and near the confluence of the splenic vein was found. After using LMWH for 22 d, CECT showed no filling defect in the portal vein system.

CONCLUSION

Although PVT after hepatectomy is rare, it needs to be prevented during the perioperative period.

Predictors of portal vein thrombosis after laparoscopic splenectomy and azygoportal disconnection in hepatitis B cirrhosis: a prospective study

BACKGROUND

The thrombosis of the main and intrahepatic branches of the portal vein (TMIP) is potentially lethal and deemed a common complication following laparoscopic splenectomy and azygoportal disconnection (LSD) in patients with cirrhosis and portal hypertension (PH). The predictors of TMIP after LSD remain unclear. The aim of this prospective study was to explore the predictive and risk factors for TMIP after LSD in cirrhotic patients with PH caused only by hepatitis B virus.

METHODS

From September 2014 to March 2017, we enrolled 115 patients with hepatitis B cirrhosis and PH who successfully underwent LSD. Patients were subdivided into a TMIP group and a non-TMIP group. Univariate and multivariate logistic regression analysis was conducted on 24 items of demographic and preoperative data, to explore the risk factors of TMIP.

RESULTS

Twenty-nine (25.22%) patients developed TMIP on postoperative day (POD) 7 and 26 (22.81%) patients developed TMIP on POD 30. From POD 7 to POD 30, 12 patients who did not have TMIP at POD 7 were newly diagnosed with TMIP, with portal vein diameter 15.05 ± 2.58 mm. Another 14 patients in whom TMIP had resolved had portal vein diameter 14.02 ± 1.76 mm. Univariate analysis and multivariate logistic regression revealed that portal vein diameter ≥ 13 mm [relative risk (RR) 5.533, 95% confidence interval (CI) 1.222-25.042; P = 0.026] and portal vein diameter ≥ 15 mm (RR 3.636, 95% CI 1.466-9.021; P = 0.005) were significant independent risk factors for TMIP on POD 7 and 30, respectively.

CONCLUSION

Portal vein diameter ≥ 13 mm and ≥ 15 mm were significant independent predictors for TMIP after LSD in patients with hepatitis B cirrhosis and PH on POD 7 and POD 30, respectively.

TRIAL REGISTRATION

We registered our research at https://www.

CLINICALTRIALS

gov/ . The name of research registered is "Warfarin Prevents Portal Vein Thrombosis in Patients After Laparoscopic Splenectomy and Azygoportal Disconnection." The trial registration identifier at clinicaltrials.gov is NCT02247414.

Evaluation of portal venous system in post splenectomised beta-thalassemic children: A prospective study in a tertiary care hospital

Background

Splenectomy is a palliative management technique in children with β-thalassemia. Portal thrombosis is the most dreaded complication after splenectomy that requires fast diagnosis, effective therapy, and good follow-up to prevent protal hypertension. Thus, there is the importance of constant evaluation of portal venous system through Color Doppler Ultrasound. This cohort study aimed to observe the changes in the portal venous system in post-splenectomised β-thalassemic children.

Material and methods

This is a prospective observational cohort study carried out on all the pediatric patients who have undergone splenectomy in Bangabandhu Sheikh Mujib Medical University, Dhaka Bangladesh from 2017 to 2019 for β-thalassemia. The color doppler of the portal venous system was done within the 7th to 10th post-operative day and after 3 months. Outcomes like mean the caliber of the portal vein, mean velocity within the portal vein, and color Doppler findings like Portal Vein Thrombosis (PVT) and Pathological change in Mean Volume (PMV) were calculated and compared in two headings: pre-operative period and postoperative period (7–10 POD and 3 months) with the help of paired t-test.

Results

Twenty-Eight β-thalassemia patients with a mean age of 10.43 ± 3.91 years planned to undergo splenectomy were included in our study. The pre-operative mean caliber and mean velocity of the portal vein were not statistically significant when compared after the postoperative period (7–10 POD and 3 months). But, continuous changes in portal vein were seen that could lead to normalization or pathological changes.

Conclusion

There are physiological and pathological changes in portal vein following splenectomy that could lead to varied complications like portal vein thrombosis and portal hypertension. Color Doppler Ultrasound findings along with close follow-up help in minimizing the pathological changes and complications.

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Splenectomy is a palliative management technique in children with β-thalassemia.

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Portal vein thrombosis and portal hypertension are dreaded complications.

Pre-operative Hemostatic Status in Dogs Undergoing Splenectomy for Splenic Masses

Portal system thrombosis is a rare but potentially fatal complication of splenectomy in dogs. The mechanism behind development of post-operative portal system thrombosis is unclear but may include alterations of portal blood flow following surgery, acquired hypercoagulability and endothelial dysfunction. The aim of the study was to evaluate hemostatic biomarkers in hemodynamically stable (heart rate <130 beats/min, blood lactate < 2.5 mMol/L) and non-anemic (hematocrit >35%) dogs prior to splenectomy for splenic masses. Our hypothesis was that this population of stable dogs would have pre-existing laboratory evidence of hypercoagulability unrelated to shock, bleeding, anemia, or other pre-operative comorbidities. Pre-operatively, abdominal ultrasonography was performed and blood was collected for platelet enumeration, prothrombin time (PT), activated partial thromboplastin time (aPTT), kaolin-activated thromboelastography (TEG), fibrinogen, von Willebrand factor activity (vWF:Ag), antithrombin and thrombin-antithrombin complex (TAT). Histopathological diagnosis and 30-day survival were recorded. None of the 15 enrolled dogs had pre-operative sonographic evidence of portal system thrombosis. Three of fifteen dogs were thrombocytopenic, three had thrombocytosis, three were hyperfibrinogenemic, one had low vWF:Ag, three had mild prolongations of PT and none had abnormal aPTT. Based on the TEG G value, 13/15 dogs were hypercoagulable (mean ± SD 13.5 ± 5.4 kd/s). Antithrombin deficiency was identified in 9/15 dogs (mean ± SD 68.7 ± 22.7%) with 5/9 having concurrently elevated TAT suggesting active thrombin generation. No dogs developed portal system thrombosis and all achieved 30-day survival. Pre-operative hypercoagulability was recognized commonly but its association with post-operative thrombosis remains undetermined.

Current status of beta-thalassemia and its treatment strategies

Background

Thalassemia is an inherited hematological disorder categorized by a decrease or absence of one or more of the globin chains synthesis. Beta‐thalassemia is caused by one or more mutations in the beta‐globin gene. The absence or reduced amount of beta‐globin chains causes ineffective erythropoiesis which leads to anemia.

Methods

Beta‐thalassemia has been further divided into three main forms: thalassemia major, intermedia, and minor/silent carrier. A more severe form among these is thalassemia major in which individuals depend upon blood transfusion for survival. The high level of iron deposition occurs due to regular blood transfusion therapy.

Results

Overloaded iron raises the synthesis of reactive oxygen species (ROS) that are noxious and prompting the injury to the hepatic, endocrine, and vascular system. Thalassemia can be analyzed and diagnosed via prenatal testing (genetic testing of amniotic fluid), blood smear, complete blood count, and DNA analysis (genetic testing). Treatment of thalassemia intermediate is symptomatic; however; it can also be accomplished by folic supplementation and splenectomy.

Conclusion

Thalassemia major can be cured through regular transfusion of blood, transplantation of bone marrow, iron chelation management, hematopoietic stem cell transplantation, stimulation of fetal hemoglobin production, and gene therapy.

Splenic volume and splenic vein diameter are independent pre-operative risk factors of portal vein thrombosis after splenectomy: a retrospective cohort study

BACKGROUND

Portal vein thrombosis (PVT) is a common complication following splenectomy. It affects between 5 and 55% of patients undergoing surgery with no clearly defined pre-operative risk factors. The aim of this study was to determine the pre-operative risk factors of PVT.

PATIENTS AND METHOD

Single centre, retrospective study of data compiled for every consecutive patient who underwent splenectomy at Toulouse University Hospital between January 2009 and January 2019. Patients with pre- and post-surgical CT scans have been included.

RESULTS

149 out of 261 patients were enrolled in the study (59% were males, mean age 52 years). The indications for splenectomy were splenic trauma (30.9%), malignant haemopathy (26.8%) and immune thrombocytopenia (8.0%). Twenty-nine cases of PVT (19.5%) were diagnosed based on a post-operative CT scan performed on post-operative day (POD) 5. Univariate analysis identifies three main risk factors associated with post-operative PVT: estimated splenic weight exceeding 500 g with an OR of 8.72 95% CI (3.3-22.9), splenic vein diameter over 10 mm with an OR of 4.92 95% CI (2.1-11.8) and lymphoma with an OR of 7.39 (2.7-20.1). The role of splenic vein diameter with an OR of 3.03 95% CI (1.1-8.6), and splenic weight with an OR of 5.22 (1.8-15.2), as independent risk factors is confirmed by multivariate analysis. A screening test based on a POD 5 CT scan with one or two of these items present could indicate sensitivity of 86.2% and specificity of 86.7%.

CONCLUSION

This study suggests that pre-operative CT scan findings could predict post-operative PVT. A CT scan should be performed on POD 5 if a risk factor has been identified prior to surgery.

Non-malignant portal vein thrombosis in a cohort of cirrhotic patients: Incidence and risk factors

AIM

Non-malignant portal vein thrombosis (PVT) is a complication of liver cirrhosis. The aim of this study was to evaluate the annual incidence of PVT and related risk factors.

METHODS

We retrospectively reviewed clinical, laboratory, and radiological data collected prospectively from September 2016 to September 2017. A follow-up of 36 months was performed in a subset of patients to determine the cumulative incidence of PVT and related complications.

RESULTS

The study included 567 patients. The incidence of PVT at 12, 24, and 36 months was 3.7%, 0.8%, and 1.4%, respectively. Patients with PVT were compared with patients without PVT, and showed differences in albumin (p = 0.04), aspartate aminotransferase (p = 0.04), hemoglobin (p = 0.01), and prothrombin activity (p = 0.01). The presence of hydropic decompensation (57.1% vs. 30.1%; p 0.004), gastroesophageal varices (76.2% vs. 39.5%; p = 0.05), variceal bleeding (52.4% vs. 22.7%; p < 0.001), hepatic encephalopathy (38.1% vs. 9.9%; p = 0.01), spontaneous bacterial peritonitis (9.5% vs. 1.7%; p < 0.001), and use of beta-blockers (71.4% vs. 27.7%; p < 0.001) were significantly associated. In the multivariate analysis, use of beta-blockers and hepatic encephalopathy appeared as risk factors, and high albumin levels a protective factor.

CONCLUSIONS

The incidence of PVT was 3.7%. Beta-blockers and hepatic encephalopathy were risks factors. High albumin levels were a protective factor.

Portal vein thrombosis following elective laparoscopic splenectomy: incidence and analysis of risk factors

BACKGROUND

Minimally invasive splenectomy is now well established for a wide range of pathologies. Portal vein thrombosis (PVT) is increasingly being recognised as a complication of splenectomy. The aim was to determine the incidence and risk factors for PVT after laparoscopic splenectomy.

METHODS

All cases of elective laparoscopic splenectomy performed from 1993 to 2020 were reviewed. Parameters recorded included demographics, diagnostic criterion and post-operative outcomes. Data were analysed using Minitab V18 with a p < 0.05 considered significant.

RESULTS

210 patients (103 female, 107 male) underwent laparoscopic splenectomy (14 to 85 years). A major proportion of cases were performed for ITP (n = 77, p = 0.012) followed by lymphoma (n = 28), indeterminate lesions (n = 21) and myelofibrosis (n = 19). Ten patients developed symptomatic portal vein thrombosis (4.8%). Patients presented most commonly with pain and fever and diagnosis was confirmed by computed tomography (CT) or ultrasonography (USS). There were 10 conversions (4.8%) to open and two postoperative deaths, one from PVT and one from pneumonia. The remaining nine patients were successfully treated with anticoagulation. Of 19 patients with myelofibrosis, six patients developed PVT (p = 0.0002). Patients who developed PVT had significantly greater specimen weights (1773 g vs 348 g, p < 0.001). Forty-three patients had a specimen weight of 1 kg or greater, and of these 9 developed portal vein thrombosis (21%), versus one with PVT of 155 with a specimen weight of less than 1 kg (p < 0.0001). Myelofibrosis (p = 0.0039), specimen weight (p < 0.001) and mean platelet count (p = 0.0049) were predictive of PVT.

CONCLUSION

A high index of suspicion for this complication should be maintained and prompt treatment with anticoagulation. High-risk patients should be considered for prophylactic anticoagulation and routine imaging of the portal vein.

Anticoagulant therapy for splanchnic vein thrombosis: a systematic review and meta-analysis

Treatment of splanchnic vein thrombosis (SVT) is challenging, and evidence to guide therapeutic decisions remains scarce. The objective of this systematic review and meta-analysis was to determine the efficacy and safety of anticoagulant therapy for SVT. MEDLINE, EMBASE, and clinicaltrials.gov were searched from inception through December 2019, without language restrictions, to include observational studies and randomized controlled trials reporting radiological or clinical outcomes in patients with SVT. Pooled proportions and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated in a random-effects model. Of 4312 records identified by the search, 97 studies including 7969 patients were analyzed. In patients receiving anticoagulation, the rates of SVT recanalization, SVT progression, recurrent venous thromboembolism (VTE), major bleeding, and overall mortality were 58% (95% CI, 51-64), 5% (95% CI, 3-7), 11% (95% CI, 8-15), 9% (95% CI, 7-12), and 11% (95% CI, 9-14), respectively. The corresponding values in patients without anticoagulation were 22% (95% CI, 15-31), 15% (95% CI, 8-27), 14% (95% CI, 9-21), 16% (95% CI, 13-20), and 25% (95% CI, 20-31). Compared with no treatment, anticoagulant therapy obtained higher recanalization (RR, 2.39; 95% CI, 1.66-3.44) and lower thrombosis progression (RR, 0.24; 95% CI, 0.13-0.42), major bleeding (RR, 0.73; 95% CI, 0.58-0.92), and overall mortality (RR, 0.45; 95% CI, 0.33-0.60). These results demonstrate that anticoagulant therapy improves SVT recanalization and reduces the risk of thrombosis progression without increasing major bleeding. The incidence of recurrent VTE remained substantial in patients receiving anticoagulation, as well. Effects were consistent across the different subgroups of patients. This trial was registered on the PROPERO database at (https://www.crd.york.ac.uk/prospero//display_record.php?ID=CRD42019127870) as #CRD42019127870.

Dual Effects of Large Spleen Volume After Splenectomy for the Patients With Chronic Liver Disease

Background

After splenectomy in patients with chronic liver disease, a large spleen was reported to be not only a risk factor of portal/splenic vein thrombosis (PSVT), but also a prediction for favorable improvement of liver function. This study aimed to evaluate the risk of PSVT and the improvement of liver function after splenectomy, with special attention to spleen volume (SV).

Methods

This studied included 50 patients who underwent splenectomy with diagnosed chronic liver disease between January 2005 and December 2017. After evaluation of risk factors for PSVT the cut-off value of SV for predicting PSVT was determined. According to the cut-off value of SV, 50 patients were divided into 2 groups: small-volume group (SVG) and large-volume group (LVG). Postoperative liver functions were compared between the 2 groups.

Results

Twenty-eight patients developed PSVT. Larger SV was the most significant independent risk factor for PSVT. The cut-off value of SV was 520 mL. Preoperatively, LVG had significantly higher total bilirubin, and MELD (model for end-stage liver disease) score, and had significantly higher rates of pancytopenia than SVG. Postoperatively, compared to SVG, platelet count, choline esterase, and total cholesterol in LVG were significantly increased.

Conclusion

After splenectomy in the patients with chronic liver disease, large SV is an independent risk factor for PSVT, with a clear benefit in improving liver function, if PSVT is properly diagnosed and managed.

Evaluation of the risk factors for venous thromboembolism post splenectomy - A ten year retrospective cohort study in St James's hospital

Background

Splenectomy is a surgical intervention for a variety of indications; benign and malignant. Complications of this procedure include Venous thromboembolism (VTE) and infection. The incidence of VTE post-surgery has been reported between 0.8%-3% depending on the type of surgery. A higher incidence of abdominal VTE was reported post splenectomy (6-11%). However, there is limited literature regarding the risk factors for post splenectomy VTE and the optimal strategy for thromboprophylaxis.

Objective

The primary objective of the study was to evaluate the incidence of VTE post splenectomy and to identify the pre-operative, intra-operative and post-operative risk factors. The secondary objective was to assess the local compliance with post-splenectomy prophylactic antibiotics and vaccination protocols.

Methods

We conducted a retrospective observational study. All patients who had a splenectomy in St James's Hospital between January 2007 and June 2017 were included and reviewed. Statistical analysis was carried out using SPSS statistical package.

Results

85 patients were involved in the study. The main indications for splenectomy were benign haematology, malignant haematology, solid tumours, traumatic and spontaneous rupture. 6/85 patients developed VTE (7.06%).High BMI ≥ 30 was associated with increased risk of VTE (p = 0.007), while the use of post-operative prophylactic anticoagulation was associated with reduced risk (p = 0.005). Other factors including age >50 years, female gender, presence of active malignancy and splenomegaly were associated with increased VTE risk with no statistical significance. All VTE's occurred in elective versus emergency splenectomy. Laparoscopic splenectomy was associated with higher risk of VTE than open splenectomy. 97% of patients were prescribed prophylactic antibiotics on discharge, but only 88% had received recommended vaccinations.

Conclusion

Venous thromboembolism is common post splenectomy. Our data showed that BMI ≥30 was associated with a statistically significant increased risk of VTE, while the use of prophylactic anticoagulation was associated with reduced risk. Further prospective studies with larger samples are warranted and a splenectomy care plan may be helpful.

Influences of Anatomorphological Features of the Portal Venous System on Postsplenectomy Hemodynamic Characteristics in Patients With Portal Hypertension: A Computational Model-Based Study

Splenectomy, as an effective surgery for relieving complications caused by portal hypertension, is often accompanied by a significantly increased incidence of postoperative thrombosis in the portal venous system (PVS). While the underlying mechanisms remain insufficiently understood, the marked changes in hemodynamic conditions in the PVS following splenectomy have been suggested to be a potential contributing factor. The aim of this study was to investigate the influences of the anatomorphological features of the PVS on hemodynamic characteristics before and after splenectomy, with emphasis on identifying the specific anatomorphological features that make postoperative hemodynamic conditions more clot-promoting. For this purpose, idealized computational hemodynamics models of the PVS were constructed based on general anatomical structures and population-averaged geometrical parameters of the PVS. In the models, we incorporated various anatomorphological variations to represent inter-patient variability. The analyses of hemodynamic data were focused on the spatial distribution of wall shear stress (WSS) and the area ratio of wall regions exposed to low WSS (ALS). Obtained results showed that preoperative hemodynamic conditions were comparable among different models in terms of space-averaged WSS and ALS (all were small) irrespective of the considerable differences in spatial distribution of WSS, whereas, the inter-model differences in ALS were significantly augmented after splenectomy, with the value of ALS reaching up to over 30% in some models, while being smaller than 15% in some other models. Postoperative ALS was mainly determined by the anatomical structure of the PVS, followed by some morphogeometrical parameters, such as the diameter and curvature of the splenic vein, and the distance between the inferior mesenteric vein and splenoportal junction. Relatively, the angles between tributary veins and trunk veins only had mild influences on ALS. In addition, a marked increase in blood viscosity was predicted after splenectomy, especially in regions with low WSS, which may play an additive role to low WSS in initiating thrombosis. These findings suggest that the anatomical structure and some morphogeometrical features of the PVS are important determinants of hemodynamic conditions following splenectomy, which may provide useful clues to assessing the risk of postsplenectomy thrombosis based on medical imaging data.

Evaluation of hemostatic abnormalities in patients who underwent major hepatobiliary pancreatic surgery using activated partial thromboplastin time-clot waveform analysis

INTRODUCTION

Bleeding after major hepatobiliary pancreatic (HBP) surgery may be serious. Although postoperative abnormality of the hemostatic system are important elements that affect bleeding, routine activated partial thromboplastin time (APTT) assessment is considered inadequate to predict massive bleeding (MB). Recently, APTT-clot waveform analysis (CWA) was reported to be useful for detecting coagulation disorders.

METHODS

APTT-CWA was performed using the ACL-TOP analyzer in 188 patients who underwent four major HBP surgeries (distal pancreatectomy, hepatectomy, subtotal stomach-preserving pancreatoduodenectomy (SSPPD), and SSPPD with combined resection and reconstruction of the portal vein) to analyze its usefulness in predicting the risk of bleeding.

RESULTS

Seventy (37.2%) patients developed MB and the incidence of MB was highest among patients who underwent hepatectomy. There were no significant differences in routine APTT, the first derivative peak (DP) time and 1/2 fibrin formation peak time between patients with MB and those without MB, throughout the postoperative course. On the other hand, the first and second DP heights were significantly lower in patients with MB than in those without MB and lowest in patients who underwent hepatectomy.

CONCLUSION

APTT-CWA was able to detect the detailed changes in the hemostatic system after major HBP surgery. The patterns of APTT-CWA after major HBP surgery differed among various surgical procedures according to invasiveness. The lower first and the second DP height, which were frequently observed in hepatectomy patients, may be useful for predicting the risk of MB.

Short- and long-term outcomes of 486 consecutive laparoscopic splenectomy in a single institution

Since its introduction in 1991, laparoscopic splenectomy (LS) has become the gold standard in elective spleen surgery in many centres. However, there still lack the report of long-term outcomes of LS with the large-scale cases. The aim of the present study was to analyze the short- and long-term outcomes of LS in a single institution over 16 years, and to compare the perioperative outcomes of totally laparoscopic splenectomy (TLS) and hand-assisted laparoscopic splenectomy (HALS) for splenomegaly.Between November 2002 and December 2018, 486 consecutive patients undergoing elective LS were enrolled in this study, including 222 TLS and 264 HALS. The intraoperative, postoperative, and follow-up data were retrospectively analyzed.The 5 most common indications were hypersplenism (71.0%), immune thrombocytopenia (14.8%), splenic benign tumor (4.5%), splenic cyst (2.9%), and splenic malignant tumor (2.9%). The mean operative time, intraoperative blood loss, and length of stay were 149.4 ± 63.3 minutes, 230.1 ± 225.1 mL, and 6.7 ± 3.2 days, respectively. The morbidity, mortality, reoperation, and conversion rate were 23.0%, 0, 0.4%, and 1.9%, respectively. Portal vein system thrombosis (PVST) was the most frequent complication with an incidence of 19.8%. The incidence of PVST in HALS was higher than that in TLS (23.9% vs 14.9%, P = .013). Compared with TLS, HALS had a shorter operative time (P = .000), lower intraoperative blood loss (P = .000), comparable conversion rate (P = .271), and morbidity (P = .922) for splenomegaly > 17.0 cm. During the follow-up period, the overall respond rate for immune thrombocytopenia was 77.8%, and the esophagogastric variceal bleeding rate was 6.9% in 320 patients with hypersplenism secondary to hepatic cirrhosis.LS is a safe, feasible, and effective procedure with satisfactory short- and long-term outcomes. HALS is a reasonable technique in patients with massive spleens.

Rivaroxaban versus low-molecular weight heparin plus warfarin prevents portal vein system thrombosis after splenectomy and pericardial devascularization: A randomized clinical trial

This study aimed to evaluate the safety and efficacy of rivaroxaban in preventing portal vein system thrombosis (PVST) in patients with liver cirrhosis after splenectomy and pericardial devascularization. 70 cirrhotic patients undergoing splenectomy and pericardial devascularization were randomly assigned to rivaroxaban treatment (n=35) or low-molecular weight heparin (LMWH) plus warfarin treatment (n=35) for 30 days in this randomized controlled trial. The primary endpoint is the PVST formation. Ultrasound doctors and radiologists were blinded to the randomization results. Both groups received routine outpatient inspection every month and were followed for one year. 17 patients (48.6 %) in rivaroxaban group developed PVST, compared with 27 patients (77.1 %) in LMWH plus warfarin group (P=0.025). The incidence of PVST during the first year postoperation was significantly lower in rivaroxaban group than in LMWH plus warfarin group (F=7.901, P=0.006). The intra-group comparisons versus baseline showed the liver function improved from POD 21 to POM 1, and coagulation function improved from POM 2, in rivaroxaban group. In contrast, the liver function improved from POM 1 to POM 2, and coagulation function improved from POM 4, in LMWH plus warfarin group. The prophylactic use of rivaroxaban significantly decreases the incidence of PVST after splenectomy and pericardial devascularization in cirrhotic patients compared to LMWH plus warfarin treatment. Besides, rivaroxaban treatment was safe and effective and associated with better liver and coagulation functions improvement than LMWH plus warfarin treatment.

Risk Factors of Portal Vein Thrombosis after Devascularization Treatment in Patients with Liver Cirrhosis: A Nested Case-Control Study

Methods

We retrospectively reviewed medical records from cirrhosis patients who underwent devascularization for the treatment of portal hypertension in our hospital between January 1, 2008, and December 20, 2014. Patients were followed up to investigate the PVT incidence at different times after surgery. Patients were divided into two groups (PVT, no PVT), and the risk factors for PVT after surgery were determined.

Results

Until October 16, 2015, the median follow-up time of the 124 patients enrolled into this study was 41.43 months (range, 5.47–95.30 months). 61 patients had perioperative PVT, and 21 (16.94%) patients had PVT diagnosed during the follow-up period. Those who had lower preoperative white blood cell counts, larger preoperative portal vein trunk diameter, and no gastric varices were more likely to have perioperative thrombosis. In those without perioperative PVT, a history of hypertension, higher grade of splenomegaly, and higher preoperative levels of creatinine were independent predictors of PVT occurrence during the follow-up period.

Conclusions

The risk factors for perioperative PVT in cirrhotic patients after devascularization were lower preoperative white blood cell count and larger portal vein trunk diameter, with no gastric varices. A history of hypertension, a larger spleen, and higher preoperative creatinine level are independent predictors of PVT during follow-up after surgery in patients without perioperative PVT.

Risk Factors and Anticoagulation Effects of Portal Vein System Thrombosis After Laparoscopic Splenectomy in Patients With or Without Cirrhosis

The clinical data of 149 patients who underwent successful laparoscopic splenectomy (LS) between January 2014 and September 2017 were analyzed in the present study. The incidence of portal vein system thrombosis (PVST) in patients with and without cirrhosis was 32.0% and 9.5%, respectively. Multiple logistic regression analysis revealed that the ratio of the postoperative maximum platelet (PLT) count to the preoperative PLT count (r=1.144; P=0.007) was the risk factor for PVST in all patients after LS. Of patients who received prophylactic anticoagulation, 9 and 6 cases of PVST in patients with and without cirrhosis, respectively, (37.5% vs. 85.7%; P=0.037) resolved during hospitalization. In patients who underwent LS, a PLT count increasing to >8 times baseline levels after surgery was the risk factor for PVST after LS, and the sensitivity to anticoagulation postoperatively was significantly higher in patients without cirrhosis than in those with cirrhosis.

Short Bowel Syndrome after Laparoscopic Procedures

Short bowel syndrome (SBS) is a potential postoperative complication after intra-abdominal procedures. Whether the laparoscopic approach is as likely to result in SBS or the causative mechanisms are similar to open procedures is unknown. Our aim was to evaluate potential mechanisms of SBS after laparoscopic procedures. The records of 175 adult patients developing SBS as a postoperative complication were reviewed. One hundred forty-seven patients had open procedures and 28 laparoscopic. Colectomy (39%), hysterectomy (11%), and appendectomy (11%) were the most common open procedures. SBS followed laparoscopic gastric bypass (46%) and cholecystectomy (32%) most frequently. The mechanisms of SBS were different: adhesive obstruction (57 vs 22%, P < 0.05) was more common in the open group, whereas volvulus (18 vs 46%, P < 0.05) was more common after laparoscopy. Overall, ischemia (25 vs 32%) was similar but significantly more laparoscopic patients had postoperative hypoperfusion (32 vs 67%, P < 0.05). Eleven of the 13 laparoscopic bariatric procedures had internal hernias and volvulus. Of the nine patients undergoing cholecystectomy, four developed ischemia early postoperatively presumably secondary to pneumoperitoneum. SBS is an increasingly recognized complication of laparoscopic procedures. The mechanisms of intestinal injury differ from open procedures with a higher incidence of volvulus and more frequent ischemia from hypoperfusion.

Long-term outcomes of oesophagogastric devascularization and splenectomy in patients with portal hypertension and liver cirrhosis

BACKGROUND

Research about the long-term outcomes of oesophagogastric devascularization and splenectomy (OGDS) to treat portal hypertension (PH) is scarce. This study aimed to evaluate the safety and long-term treatment efficacy of OGDS, especially in elderly patients.

METHODS

During 2010-2016, open splenectomy and oesophagogastric devascularization (OSOD) and laparoscopic splenectomy and oesophagogastric devascularization were performed in 124 (group A) and 29 (group C) patients diagnosed with PH and liver cirrhosis, respectively. All patients aged less than 65 years. Besides, 39 patients aged 65 years or older undergoing open splenectomy and oesophagogastric devascularization were classified into group B. All clinical data were retrospectively analysed.

RESULTS

Compared with group A, patients in group C had longer operative time, less blood loss and shorter post-operative hospitalization time. However, for perioperative data, there was no significant difference between group A and group B. During post-operative follow-up, compared with pre-operative condition, all haematology and liver function parameters significantly changed, except for alanine aminotransferase. For post-operative complications, only the portal vein system thrombosis rate was significantly higher in group C than group A. No significant difference was found in the overall survival rate among three groups, when non-variceal-rebleeding-related deaths were excluded.

CONCLUSION

OGDS remains safe and effective to treat PH secondary to liver cirrhosis and it can be performed successfully in elderly patients and achieve a curative effect that is not inferior to young patients.

Low-molecular weight heparin prevents portal vein system thrombosis after splenectomy: a systematic review and meta-analysis

Background

The aim of this study was to evaluate the safety and efficacy of low‐molecular weight heparin (LMWH) in the prevention of portal vein system thrombosis (PVST) after splenectomy.

Methods

A systematic search was performed using PubMed, EMBASE, Springer and Cochrane Library databases to screen out studies comparing the prognoses between post‐splenectomy patients treated with and without LMWH. The incidences of PVST and bleeding complications were used as parameters to assess the effect of LMWH.

Results

Six articles met the selection criteria and were included in this study. A total of 740 patients were involved in these six articles, including 336 patients treated with LMWH (LMWH group) and 385 patients not treated with LMWH (control group). The incidence of PVST in the LMWH group was significantly lower than that in the control group (relative risk 1.782 (1.449–2.192); P = 0.285; I² = 19.7%), while the incidence of post‐operative bleeding in the LMWH group was significantly higher (relative risk 0.592 (0.195–1.799); P = 0.817; I² = 0.0%).

Conclusion

LMWH might decrease the incidence of PVST after splenectomy without a potential risk of bleeding.

An outcome analysis of predictive factors for portal or splenic vein thrombosis after distal pancreatectomy

PURPOSES

The aim of this study was to explore predictive factors for portal or splenic vein thrombosis (VT) that might cause serious problems after distal pancreatectomy (DP).

METHODS

A total of 230 patients who underwent DP between 2008 and 2017 were retrospectively reviewed to identify predictive factors for portal or splenic VT.

RESULTS

Ultimately, 164 patients were analyzed. Portal or splenic VT was significantly correlated with age < 65 years old, benign tumor, laparoscopic surgery, preservation of the inferior mesenteric vein (IMV) and left gastric vein (LGV), preservation of the IMV only, no drainage vein, length of the residual splenic vein (RSV) ≥ 26 mm, vessel dissection with a linear stapler, and intra-abdominal abscess (all P < 0.05). Furthermore, a multivariate analysis indicated that the length of the RSV (odds ratio [OR]: 9.15, P = 0.03) was an independent predictive factor for portal VT and that the length of the RSV (OR: 37.9, P < 0.01), vessel dissection with a linear stapler (OR: 6.49, P = 0.03), and intra-abdominal abscess (OR: 23.0, P = 0.02) were independent predictive factors for splenic VT.

CONCLUSION

As the length of the RSV was significantly associated with portal or splenic VT, a follow-up imaging diagnosis might be recommended for such cases.

A novel method detecting the key clinic factors of portal vein system thrombosis of splenectomy & cardia devascularization patients for cirrhosis & portal hypertension

BACKGROUND

Portal vein system thrombosis (PVST) is potentially fatal for patients if the diagnosis is not timely or the treatment is not proper. There hasn't been any available technique to detect clinic risk factors to predict PVST after splenectomy in cirrhotic patients. The aim of this study is to detect the clinic risk factors of PVST for splenectomy and cardia devascularization patients for liver cirrhosis and portal hypertension, and build an efficient predictive model to PVST via the detected risk factors, by introducing the machine learning method. We collected 92 clinic indexes of splenectomy plus cardia devascularization patients for cirrhosis and portal hypertension, and proposed a novel algorithm named as RFA-PVST (Risk Factor Analysis for PVST) to detect clinic risk indexes of PVST, then built a SVM (support vector machine) predictive model via the detected risk factors. The accuracy, sensitivity, specificity, precision, F-measure, FPR (false positive rate), FNR (false negative rate), FDR (false discovery rate), AUC (area under ROC curve) and MCC (Matthews correlation coefficient) were adopted to value the predictive power of the detected risk factors. The proposed RFA-PVST algorithm was compared to mRMR, SVM-RFE, Relief, S-weight and LLEScore. The statistic test was done to verify the significance of our RFA-PVST.

RESULTS

Anticoagulant therapy and antiplatelet aggregation therapy are the top-2 risk clinic factors to PVST, followed by D-D (D dimer), CHOL (Cholesterol) and Ca (calcium). The SVM (support vector machine) model built on the clinic indexes including anticoagulant therapy, antiplatelet aggregation therapy, RBC (Red blood cell), D-D, CHOL, Ca, TT (thrombin time) and Weight factors has got pretty good predictive capability to PVST. It has got the highest PVST predictive accuracy of 0.89, and the best sensitivity, specificity, precision, F-measure, FNR, FPR, FDR and MCC of 1, 0.75, 0.85, 0.92, 0, 0.25, 0.15 and 0.8 respectively, and the comparable good AUC value of 0.84. The statistic test results demonstrate that there is a strong significant difference between our RFA-PVST and the compared algorithms, including mRMR, SVM-RFE, Relief, S-weight and LLEScore, that is to say, the risk indicators detected by our RFA-PVST are statistically significant.

CONCLUSIONS

The proposed novel RFA-PVST algorithm can detect the clinic risk factors of PVST effectively and easily. Its most contribution is that it can display all the clinic factors in a 2-dimensional space with independence and discernibility as y-axis and x-axis, respectively. Those clinic indexes in top-right corner of the 2-dimensional space are detected automatically as risk indicators. The predictive SVM model is powerful with the detected clinic risk factors of PVST. Our study can help medical doctors to make proper treatments or early diagnoses to PVST patients. This study brings the new idea to the study of clinic treatment for other diseases as well.

Doppler ultrasonographic evaluation of brachial and femoral veins, and coagulation and lipid profiles in dogs following open splenectomy

In dogs, splenectomy is mandatory as an emergency following splenic rupture with resultant hemoperitoneum and hypotensive shock. The present work aimed to evaluate the Doppler ultrasonographic parameters of brachial and femoral veins in splenectomized dogs and to investigate the effect of splenectomy on the coagulation and lipid profiles. A total number of 9 dogs underwent clinical, abdominal ultrasonographic and laboratory examinations prior to the surgical operation and kept for 60-day observation period post-splenectomy. Follow-up ultrasonography revealed no serious complications post-splenectomy. Both brachial and femoral veins were imaged medial to their corresponding arteries. Doppler ultrasonographic parameters of both veins showed no significant changes throughout the study period (P > 0.05). Haematological analysis revealed development of anemia, leukocytosis, and thrombocytosis in dogs post-splenectomy. Coagulation profile exhibited no significant variations in prothrombin and activated partial thromboplastin times (P > 0.05). In comparison with their baseline values, the mean concentrations of total cholesterol, low-density lipoprotein, and triglycerides were significantly increased 30-day post-splenectomy. In conclusion, it may seem that open splenectomy has no influence on the Doppler ultrasonographic indices of brachial and femoral veins with no evidence of deep vein thrombosis in dogs. However, persistent leukocytosis and thrombocytosis, as well as altered lipid profile may increase the risk of vascular complications with the long run. Therefore, a further long-term study may be required.

Case series: Portomesenteric venous thrombosis complicating laparoscopic bariatric procedures

•

Portomesenteric vein thrombosis is a rare but potentially fatal complication of bariatric surgery.

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Portomesenteric venous thrombosis complicated 3 of 1030 cases (0.29%).

•

Management is primarily with anticoagulants, but surgery is required if the patient shows signs of sepsis.

•

A high index of suspicion, early diagnosis and subsequent adequate management is required.

Introduction

Portomesenteric vein thrombosis is a rare but documented complication of laparoscopic surgery. This rare complication is currently being encountered more frequently with the increase in the rates of laparoscopic bariatric surgery procedures being performed worldwide.

Methods

A retrospective analysis was performed on all bariatric procedures performed in our center between July 2012 & December 2017 to identify cases complicated by portomesenteric venous thrombosis. The cases were compared in terms of operative details, patient presentation, diagnosis, patient risk factors for developing thrombosis, demographics and thrombophilia analysis & subsequent treatment and prognosis.

Results

A total of 1030 bariatric procedures were performed between July 2012 & December 2017. Portomesenteric venous thrombosis complicated 3 of these cases (0.29%). Two of these cases had underwent a laparoscopic sleeve gastrectomy while the third had underwent a gastric band removal and a conversion to a single anastomosis gastric bypass. Amongst these patients, 2 were female while 1 was male with an average BMI 38.9 kg/m². Only one of these patients was a smoker while none of them tested positive for thrombophilias. The diagnosis of portomesenteric venous thrombosis was confirmed with a contrast CT of the abdomen as all patients were re-admitted between 4–20 days post operatively after being discharged on postoperative day 2. All three cases were managed with systemic anticoagulants and none underwent invasive procedures or were re-explored surgically. All were subsequently discharged in good condition.

Conclusion

Portomesenteric venous thrombosis is an uncommon yet potentially fatal complication of bariatric surgery. A high index of suspicion, early diagnosis and subsequent adequate management is required. Based on this case series and the potential risk of portomesenteric venous thrombosis, we altered our clinical practice to include a 1 week course of low molecular weight heparin to be administered to all patients after discharge.

Predicting venous thrombosis in patients undergoing elective splenectomy

BACKGROUND

Venous thrombosis (VT) is an ongoing problem for patients undergoing elective splenectomy. There is limited data evaluating risk factors for VTs. An increase in platelet counts is commonly seen after splenectomy; however, there is a paucity of literature evaluating post-operative platelet counts as a risk factor for VTs in this patient cohort. The objective of this study was to determine the incidence of VT events and to use the platelet count as a predictor for VT development.

METHODS

A retrospective review was undertaken at Brigham Women's Hospital, evaluating elective splenectomy patients between 1997 and 2018. Descriptive statistics were utilized to determine the incidence of VTs. Receiver operator characteristic (ROC) curves were utilized to identify platelet counts that could predict VTs.

RESULTS

Five hundred and twenty splenectomies were included in the study of which 344 were completed in an open manner and 176 were done laparoscopically. The overall incidence of VT events was 6.7% (35/520), 6.1% (21/344) for open, and 8.0% (14/176) for laparoscopic approaches (p = 0.43). ROC curves demonstrated platelet counts to be a good predictor for the development of VTs with an area under the curve (AUC) of 0.77 (95% CI 0.69-0.86; p < 0.001) for all splenectomy patients, 0.70 (95% CI 0.59-0.81; p < 0.001) for those completed in an open manner, and 0.88 (95% CI 0.77-0.99; p < 0.001) for those done laparoscopically. The optimal platelet cutoff was found to be 545 for the overall splenectomy cohort, 457 for the open, and 659 for the laparoscopic cohorts. These platelet counts had a diagnostic accuracy that ranged from 61 to 86% and a negative predictive value (NPV) that ranged from 97 to 99%.

CONCLUSION

These results suggest platelet cutoffs that predict VTs. This information can be used to individualize prophylactic strategies.

Effect of low-dose aspirin administration on long-term survival of cirrhotic patients after splenectomy: A retrospective single-center study

BACKGROUND

Cirrhosis is a major risk factor for the development of hepatocellular carcinoma (HCC). Portal vein thrombosis is not uncommon after splenectomy in cirrhotic patients, and many such patients take oral anticoagulants including aspirin. However, the long-term impact of postoperative aspirin on cirrhotic patients after splenectomy remains unknown.

AIM

The main purpose of this study was to investigate the effect of postoperative long-term low-dose aspirin administration on the development of HCC and long-term survival of cirrhotic patients after splenectomy.

METHODS

The clinical data of 264 adult patients with viral hepatitis-related cirrhosis who underwent splenectomy at the First Affiliated Hospital of Xi’an Jiaotong University from January 2000 to December 2014 were analyzed retrospectively. Among these patients, 59 who started taking 100 mg/d aspirin within seven days were enrolled in the aspirin group. The incidence of HCC and overall survival were analyzed.

RESULTS

During follow-up, 41 (15.53%) patients developed HCC and 37 (14.02%) died due to end-stage liver diseases or other serious complications. Postoperative long-term low-dose aspirin therapy reduced the incidence of HCC from 19.02% to 3.40% after splenectomy (log-rank test, P = 0.028). Univariate and multivariate analyses showed that not undertaking postoperative long-term low-dose aspirin therapy [odds ratio (OR) = 6.211, 95% confidence interval (CI): 1.142-27.324, P = 0.016] was the only independent risk factor for the development of HCC. Similarly, patients in the aspirin group survived longer than those in the control group (log-rank test, P = 0.041). Univariate and multivariate analyses showed that the only factor that independently associated with improved overall survival was postoperative long-term low-dose aspirin therapy [OR = 0.218, 95%CI: 0.049-0.960, P = 0.044].

CONCLUSION

In patients with viral hepatitis-related cirrhosis, long-term post-splenectomy administration of low-dose aspirin reduces the incidence of HCC and improves the long-term overall survival.

A Diagnostic Prediction Model of Acute Symptomatic Portal Vein Thrombosis

BACKGROUND

The aim of this study was to develop a diagnostic prediction model to improve identification of acute symptomatic portal vein thrombosis (PVT).

METHODS

We examined 47 patients with PVT and 94 controls without PVT in the Second Affiliated Hospital of Soochow University and Suqian People's Hospital of Nanjing, Gulou Hospital Group. We constructed a prediction model by using a support vector machine (SVM) classifier coupled with a least absolute shrinkage and selection operator (LASSO). We applied a 10-fold cross-validation to estimate the error rate for each model.

RESULTS

The present study indicated that acute symptomatic PVT was associated with 11 indicators, including liver cirrhosis, D-Dimer, splenomegaly, splenectomy, inherited thrombophilia, ascetic fluid, history of abdominal surgery, bloating, C-reactive protein (CRP), albumin, and abdominal tenderness. The LASSO-SVM model achieved a sensitivity of 91.5% and a specificity of 100.0%.

CONCLUSIONS

We developed a LASSO-SVM model to diagnose PVT. We demonstrated that the model achieved a sensitivity of 91.5% and a specificity of 100.0%.

Simultaneous radiofrequency ablation combined with laparoscopic splenectomy: a safe and effective way for patients with hepatocellular carcinoma complicated with cirrhosis and hypersplenism

Purpose: This study aimed to evaluate the safety and effectiveness of simultaneous radiofrequency ablation (RFA) combined with laparoscopic splenectomy (Lap-Sp) for patients with hepatocellular carcinoma (HCC) complicated with cirrhosis and hypersplenism.Material and methods: Between January 2013 and June 2014, 42 patients with primary HCC complicated with cirrhosis and hypersplenism who underwent simultaneous RFA combined with Lap-Sp were enrolled at the Department of General Surgery, Beijing Di Tan Hospital. The median number of tumors ablated using RFA was one (range 1-3), and the median sum of the maximum diameter of tumors was 2.5 cm (range 1.2-5.4 cm). The related indicators before and after surgery, complications, and long-term effects were retrospectively analyzed.Results: The median operative time for 42 patients undergoing simultaneous RFA combined with Lap-Sp was 4.5 h (range 2.5-8.5 h), and the median blood loss was 120 mL (range 5-2200 mL). The incidence of moderate-to-severe postoperative complications and the perioperative mortality after surgery were 31.0 and 0%, respectively. The disease-free survival rate for one, three, and five years was 73.8, 19.7, and 16.4%, respectively. The overall survival rate was 90.5, 73.3, and 60.4%, respectively.Conclusion: Simultaneous RFA combined with Lap-Sp was safe and effective for patients with HCC complicated with cirrhosis and hypersplenism.

Venous Thromboembolism in Special Populations: Preexisting Cardiopulmonary Disease, Cirrhosis, End-Stage Renal Disease, and Asplenia

Venous thromboembolism (VTE) is a common cause of morbidity and mortality. Presence of preexisting conditions, such as cardiopulmonary diseases, cirrhosis, renal dysfunction, and asplenia, commonly occurs in VTE patients. Moreover, these conditions often are risk factors for developing VTE. These preexisting conditions make VTE diagnosis and treatment challenging and worsen outcomes. Current guidelines do not include detailed features in the diagnosis and management of patients with preexisting conditions. This review discusses presence of VTE in patients with preexisting cardiopulmonary diseases, cirrhosis, renal dysfunction, and asplenia.

Warfarin versus aspirin prevents portal vein thrombosis after laparoscopic splenectomy and azygoportal disconnection: A randomized clinical trial

INTRODUCTION

Portal vein system thrombosis (PVST) is a common, potentially life-threatening complication after splenectomy. The optimal recognized anticoagulation drugs for preventing PVST in cirrhotic patients after splenectomy remain unclear. The aim of this study is to evaluate the safety and efficacy of warfarin in preventing PVST after laparoscopic splenectomy and azygoportal disconnection (LSD).

METHODS

In this randomized controlled single-center study, 80 cirrhotic patients who underwent LSD were randomly assigned to 2 years of treatment with either warfarin (n = 40) or aspirin (n = 40). The primary outcome was prevention of PVST. Sonographers and radiologists who assessed outcomes were blinded to group assignments. Intention-to-treat analysis was performed.

RESULTS

During the first year, excluding two patients withdrawing from the study, 15 of the 39 warfarin-treated patients (38.5%) and five of the 39 aspirin-treated patients (12.8%) did not develop PVST (P = 0.010). The incidence of PVST in the first 2 postoperative years was significantly lower in the warfarin group than in the aspirin group (F = 7.360, P = 0.008). The warfarin group in paired within-group comparisons had significantly greater improvements in total bilirubin and albumin levels at baseline versus at 6 months postoperatively and in creatinine levels at baseline versus at 12, 18, and 24 months postoperatively respectively (all P < 0.05). In contrast, those paired comparisons of the aspirin group showed no significant differences (all P > 0.05).

CONCLUSIONS

Warfarin therapy was safe and effective and significantly reduced the risk of PVST after LSD, compared with aspirin treatment. Warfarin treatment was associated with better liver function protection and renal function improvement than aspirin treatment.

Thrombocytosis and portal vein thrombosis after splenectomy for paediatric haemolytic disorders: How should they be managed?

Splenectomy is indicated in selected children with haemolytic anaemia. Postoperatively, thrombocytosis occurs in at least 80% and is one of the factors implicated in the development of acute portal venous thrombosis after splenectomy in adults. A literature review shows that children are also at risk of this complication, but the incidence is low. The risk is greatest in those with particularly large spleens. Laparoscopic splenectomy does not reduce the risk of this complication. Early detection and anticoagulation usually leads to successful resolution of the thrombosis and can mitigate the risk of developing cavernous transformation of the portal vein and chronic portal hypertension. Any child with severe or unexplained postoperative abdominal pain, fever and/or vomiting after splenectomy demands urgent abdominal imaging to exclude this complication. In asymptomatic individuals, a routine Doppler ultrasound scan 1 week postoperatively is advisable if they had a particularly large spleen, longer than usual duration of surgery and/or have a marked postoperative thrombocytosis. There is no evidence for routine administration of antiplatelet drugs and/or subcutaneous heparin prophylaxis in children after splenectomy, including those who develop postoperative thrombocytosis, but children with particularly large spleens may be a subset that benefit.

Venous thrombosis in unusual sites: A practical review for the hematologist

Thrombosis of unusual venous sites encompasses a large part of consultative hematology and is encountered routinely by practicing hematologists. Contrary to the more commonly encountered lower extremity venous thrombosis and common cardiovascular disorders, the various thromboses outlined in this review have unique presentations, pathophysiology, workup, and treatments that all hematologists should be aware of. This review attempts to outline the most up to date literature on cerebral, retinal, upper extremity, hepatic, portal, splenic, mesenteric, and renal vein thrombosis, focusing on the incidence, pathophysiology, provoking factors, and current recommended treatments for each type of unusual thrombosis to provide a useful and practical review for the hematologist.

Portomesenteric Thrombosis Secondary to Acute Cholecystitis: A Case Report

Portomesenteric venous thrombosis (PMVT) is an uncommon clinical problem. Common risk factors include intra-abdominal infections, abdominal surgeries, malignancy, cirrhosis, and inherited thrombophilia. Early recognition and treatment of PMVT are important to avoid serious complications like mesenteric ischemia and infarction. Acute cholecystitis is a clinical condition encountered daily but rarely may be complicated by development of portomesenteric venous thrombosis. Only few cases have been reported of superior mesenteric vein thrombosis secondary to cholecystitis. We report a case of a forty-one-year-old male patient who developed partial portal and superior mesenteric vein thrombosis after mild acute cholecystitis for which surgery had been deferred. Patient had no other identifiable risk factors for thrombosis. Patient was successfully treated with 6 months of anticoagulation with warfarin and complete recanalization of portomesenteric veins was achieved at the end of treatment.

Predictors of portal and splenic vein thrombosis after laparoscopic splenectomy: a retrospective analysis of a single-center experience

PURPOSE

Laparoscopic splenectomy (LS) has become the standard operative approach for splenectomy. Portal or splenic vein thrombosis (PSVT) is a serious and common complication after LS, and lethal complications of PSVT can occur when the portal vein is completely occluded by portal vein thrombosis (PVT). We aimed to clarify the predictors of PSVT after LS and to determine which of them were also predictors of PVT.

METHODS

A total of 56 consecutive patients who underwent elective LS were enrolled in this study. The patients were divided into two groups based on the presence or absence of PSVT after LS. In addition, patients with PSVT were divided into two groups: a PVT group and a non-PVT group. The preoperative and intraoperative clinical data were compared among the groups.

RESULTS

Thirty (53.6%) patients developed PSVT. The splenic vein diameter was the most useful predictor for the development of PSVT, and 10 mm was an accurate splenic vein diameter cut-off value for use as a predictive factor for PSVT. In addition, the splenic vein diameter was the most useful predictor of the development of PVT from splenic vein thrombosis (SVT), and 14 mm was found to be an accurate cut-off value.

CONCLUSION

PSVT is a common postoperative complication that is identified on enhanced computed tomography. The splenic vein diameter is not only a predictor of PSVT but also of the development of PVT from SVT.

Splenectomy Versus Sham Splenectomy in a Swine Model of Controlled Hemorrhagic Shock

INTRODUCTION

Splenectomy is controversial in acute hemorrhagic shock models.

OBJECTIVE

To compare splenectomized (SP) versus sham-splenectomized (SSP) swine during acute controlled hemorrhage.

METHODS

Twenty-six male Landrace White swine (mean body weight ± standard deviation, 33.8 ± 2.9 kg) were used. Ethics approval was obtained. Landrace swine underwent splenectomy (n = 13) or sham-splenectomy (n = 13), were bled to mean arterial blood pressure (MAP) of 40 mm Hg, which was held for 60 min, given 125 mL IV RescueFlow, held for a further 60 min, given whole blood, and held for a final 60 min. Tissue oxygen saturation, thromboelastography, oncotic pressure, urine volume and specific gravity, complete blood count, serum chemistry, body temperature, hematocrit, total solids, arterial and mixed venous blood gas, bispectral index, SAP, MAP, DAP, cardiac index, total blood volume (TBV) removed and returned, rate of hemorrhage and transfusion, spleen weight, heart rate (HR), arterial pH, lactate, PaO2, PaCO2, respiratory rate, cranial mesenteric and renal artery blood flow were recorded. Groups were compared using two-way ANOVA with post hoc Bonferroni (P < 0.05) for repeated measures or t test for non-repeated measures.

RESULTS

Compared with the SSP swine, SP swine had higher HR post-splenectomy for the duration of the experiment (P < 0.03), and higher hematocrits at 15 and 60 min post splenectomy (P < 0.01, P < 0.001, respectively). SSP swine had greater TBV removed during hemorrhage (P < 0.01); however, when blood loss based on splenic weight was considered, TBV removed was similar between groups.

CONCLUSION

Splenectomy likely accounts for the transient increase in hematocrit and the higher HR in SP swine prior to hemorrhage, and the differences in TBV removed between the two groups during hemorrhage. With a fixed end point model using a moderate rate of acute hemorrhage and an MAP of 40 mm Hg, splenectomy is not necessary and may confound results.

Splenectomy in systemic lupus erythematosus and autoimmune hematologic disease: a comparative analysis

The objective of the study is to analyze the efficacy and safety of splenectomy in the management of refractory autoimmune thrombocytopenia (AT)/autoimmune hemolytic anemia (AIHA) associated or not with systemic lupus erythematosus. Thirty-four patients after splenectomy due to severe AT and/or AIHA were divided into group 1 (G1) 18 SLE/APS patients: 9 AT/SLE patients, 6 SLE/antiphospholipid syndrome (APS), and 3 primary APS. Group 2 (G2): 16 patients without SLE/APS: 2 Fisher-Evans syndrome and 14 AIHA. Surgery approach when (1) platelets ≤ 50,000/ml despite 2 weeks on medical therapy, (2) medically dependent, and (3) medically intolerant or after two hemolytic crises in AIHA patients. Splenectomy response: (1) complete (CR): ≥ 150,000 platelets/ml, (2) partial: 50,000-149,000/ml, or (3) none: ≤ 50,000/ml. CR for AIHA: hemoglobin ≥9 g/dl.

STATISTICAL ANALYSIS

descriptive statistics and chi-square test. The mean age was 34.6 years; mean follow-up: 28.5 months. Open splenectomy in 15/34 vs laparoscopy in 19/34 (p = NS). CR in 15/34, G1: 4/18, G2: 11/16, (p = 0.006). Complications in 6/34, 5 from G2 vs 1 from G1 (p = 0.05). Relapse in 7/18 patients in G1 and 3/16 in G2 (p = 0.05). Open and laparoscopic splenectomies in SLE and AT patients are as effective as in those without SLE; however, patients with SLE and APS had more relapses.