The impact of urgency of umbilical hernia repair on adverse outcomes in patients with cirrhosis: a population-based cohort study from England

INTRODUCTION

Umbilical hernia is common in patients with cirrhosis; however, there is a paucity of dedicated studies on postoperative outcomes in this group of patients. This population-based cohort study aimed to determine the outcomes after emergency and elective umbilical hernia repair in patients with cirrhosis.

METHODS

Two linked electronic healthcare databases from England were used to identify all patients undergoing umbilical hernia repair between January 2000 and December 2017. Patients were grouped into those with and without cirrhosis and stratified by severity into compensated and decompensated cirrhosis. Length of stay, readmission, 90-day case fatality rate and the odds ratio of 90-day postoperative mortality were defined using logistic regression.

RESULTS

In total, 22,163 patients who underwent an umbilical hernia repair were included and 297 (1.34%) had cirrhosis. More patients without cirrhosis had an elective procedure, 86% compared with 51% of those with cirrhosis (P < 0.001). In both the elective and emergency settings, patients with cirrhosis had longer hospital length of stay (elective: 0 vs 1 day, emergency: 2 vs 4 days, P < 0.0001) and higher readmission rates (elective: 4.87% vs 11.33%, emergency:11.39% vs 29.25%, P < 0.0001) than those without cirrhosis. The 90-day case fatality rates were 2% and 0.16% in the elective setting, and 19% and 2.96% in the emergency setting in patients with and without cirrhosis respectively.

CONCLUSION

Emergency umbilical hernia repair in patients with cirrhosis is associated with poorer outcomes in terms of length of stay, readmissions and mortality at 90 days.

Long-term risk of venous thromboembolism among patients with gastrointestinal non-neoplastic and neoplastic diseases: A prospective cohort study of 484 211 individuals

We conducted a prospective cohort study to examine the associations of 21 gastrointestinal diseases with the risk of incident venous thromboembolism (VTE). The study included 485 936 UK Biobank participants free of baseline VTE. The gastrointestinal diseases were defined by the International Classification of Disease (ICD)-9 and 10 codes with data from the nationwide inpatient data set, the primary care data set, and the cancer registries. Incident VTE cases were defined by ICD-9 and 10 codes with data from the nationwide inpatient data set. Cox proportional hazards regression was used to estimate the associations of baseline gastrointestinal diseases with incident VTE risk. During a median follow-up of 12.0 years, 13 646 incident VTE cases were diagnosed. Eleven gastrointestinal diseases (nine non-neoplastic and two neoplastic) were associated with an increased risk of incident VTE after Bonferroni corrections. The risk of VTE was >50% higher among patients with gallbladder and biliary tract cancer (hazard ratio [HR] 3.15, 95% confidence interval [CI] 95% CI 1.74-5.70), pancreatic cancer (HR 2.84, 95% CI 1.65-4.91), cirrhosis (HR 2.34, 95% CI 1.96-2.79), Crohn's disease (HR 1.61, 95% CI 1.33-1.95), or pancreatitis (HR 1.57, 95% CI 1.31-1.88) compared with individuals without each of these diseases. We observed multiplicative interactions of age, sex, and body mass index with some gastrointestinal diseases (p < .05). A more pronounced, increased risk of VTE was found among younger, female, or obese patients. The study suggests a 50% higher risk of developing VTE among patients with gallbladder and biliary tract cancer, pancreatic cancer, cirrhosis, Crohn's disease, or pancreatitis.

Outcomes after emergency appendicectomy in patients with liver cirrhosis: a population-based cohort study from England

INTRODUCTION

The mortality risk after appendicectomy in patients with liver cirrhosis is predicted to be higher than in the general population given the associated risk of perioperative bleeding, infections and liver decompensation. This population-based cohort study aimed to determine the 90-day mortality risk following emergency appendicectomy in patients with cirrhosis.

METHODS

Adult patients undergoing emergency appendicectomy in England between January 2001 and December 2018 were identified from two linked primary and secondary electronic healthcare databases, the clinical practice research datalink and hospital episode statistics data. Length of stay, re-admission, case fatality and the odds ratio of 90-day mortality were calculated for patients with and without cirrhosis, adjusting for age, sex and co-morbidity using logistic regression.

RESULTS

A total of 40,353 patients underwent appendicectomy and of these 75 (0.19%) had cirrhosis. Patients with cirrhosis were more likely to be older (p < 0.0001) and have comorbidities (p < 0.0001). Proportionally, more patients with cirrhosis underwent an open appendicectomy (76%) compared with 64% of those without cirrhosis (p = 0.03). The 90-day case fatality rate was 6.67% in patients with cirrhosis compared with 0.56% in patients without cirrhosis. Patients with cirrhosis had longer hospital length of stay (4 (IQR 3-9) days versus 3 (IQR 2-4) days and higher readmission rates at 90 days (20% vs 11%, p = 0.019). Most importantly, their odds of death at 90 days were 3 times higher than patients without cirrhosis, adjusted odds ratio 3.75 (95% CI 1.35-10.49).

CONCLUSION

Patients with cirrhosis have a threefold increased odds of 90-day mortality after emergency appendicectomy compared to those without cirrhosis.

Risk of Postoperative Venous Thromboembolism After Benign Colorectal Surgery: Systematic Review and Meta-analysis

BACKGROUND

Venous thromboembolism is a well-established preventable complication after colectomy. Specific guidance on venous thromboembolism prevention after colectomy for benign disease is limited.

OBJECTIVE

This meta-analysis aimed to quantify the venous thromboembolism risk after benign colorectal resection and determine its variability.

DATA SOURCES

Following Preferred Reporting Items for Systematic Review and Meta-Analysis and Meta-analysis of Observational Studies in Epidemiology Guidelines (PROSPERO: CRD42021265438), Embase, MEDLINE, and 4 other registered medical literature databases were searched from the database inception to June 21, 2021.

STUDY SELECTION

Inclusion criteria: randomized controlled trials and large population-based database cohort studies reporting 30-day and 90-day venous thromboembolism rates after benign colorectal resection in patients aged ≥18 years. Exclusion criteria: patients undergoing colorectal cancer or completely endoscopic surgery.

MAIN OUTCOME MEASURES

Thirty- and 90-day venous thromboembolism incidence rates per 1000 person-years after benign colorectal surgery.

RESULTS

Seventeen studies were eligible for meta-analysis reporting on 250,170 patients. Pooled 30-day and 90-day venous thromboembolism incidence rates after benign colorectal resection were 284 (95% CI, 224-360) and 84 (95% CI, 33-218) per 1000 person-years. Stratified by admission type, 30-day venous thromboembolism incidence rates per 1000 person-years were 532 (95% CI, 447-664) for emergency resections and 213 (95% CI, 100-453) for elective colorectal resections. Thirty-day venous thromboembolism incidence rates per 1000 person-years after colectomy were 485 (95% CI, 411-573) for patients with ulcerative colitis, 228 (95% CI, 181-288) for patients with Crohn's disease, and 208 (95% CI, 152-288) for patients with diverticulitis.

LIMITATIONS

High degree of heterogeneity was observed within most meta-analyses attributable to large cohorts minimizing within-study variance.

CONCLUSIONS

Venous thromboembolism rates remain high up to 90 days after colectomy and vary by indication for surgery. Emergency resections compared to elective benign resections have higher rates of postoperative venous thromboembolism. Further studies reporting venous thromboembolism rates by type of benign disease need to stratify rates by admission type to more accurately define venous thromboembolism risk after colectomy.

REGISTRATION NO

CRD42021265438.

The risk of venous thromboembolism after minor surgical procedures: A population-based case-control study

BACKGROUND

Surgery is a well-known risk factor for venous thromboembolism (VTE). However, for several minor surgical procedures, thromboprophylaxis is not advised.

OBJECTIVES

These "low-risk" procedures include a wide variation of interventions for which we estimated the VTE risk to verify their "low-risk" status.

PATIENTS/METHODS

We used data from a large population-based case-control study (Multiple Environment and Genetic Assessment study) into causes of VTE, and linked these to the Dutch Hospital Data Registry to identify exposure to surgical procedures. Logistic regression was used to calculate odds ratios for the 90-day and 1-year relative risks of VTE following these procedures, which were adjusted for body mass index (BMI), sex, age, comorbidities, and infection/inflammation.

RESULTS

We included 4247 patients with VTE and 5538 control subjects. Median age and BMI were 48.5 years and 25.5 m²/kg, respectively. Nine unique procedures or groups of procedures were analyzed. One hundred twenty-three participants-90 cases and 33 controls-had undergone a minor procedure within 90 days of the index date, resulting in a 3.5-fold (OR, 3.5; 95% CI, 2.3-5.3) overall increased VTE risk. Furthermore, venous stripping (OR, 7.2; 95% CI, 2.4-21.2), open abdominal/inguinal hernia repair (OR, 3.7; 95% CI, 1.2-11.6), and laparoscopic cholecystectomy (OR, 3.2; 95% CI, 1.0-10.6) were associated with an increased risk. Other minor procedures were less strongly or not associated with an increased risk. In the 1-year period before the index date, all odds ratios were lower.

CONCLUSION

Of the "low-risk" procedures, we found that venous stripping, open abdominal/inguinal hernia repair, and laparoscopic cholecystectomy were associated with a clearly increased risk of VTE within 90 postoperative days.

Cholecystectomy in patients with cirrhosis: a population-based cohort study from England

BACKGROUND

This population-based cohort study aimed to determine postoperative outcomes after emergency and elective cholecystectomy in patients with cirrhosis.

METHODS

Linked electronic healthcare data from England were used to identify all patients undergoing cholecystectomy between January 2000 and December 2017. Length of stay (LOS), re-admission, case fatality and the odds ratio of 90-day mortality were calculated for patients with and without cirrhosis, adjusting for age, sex and co-morbidity using logistic regression.

RESULTS

Of the total 69,141 eligible patients who underwent a cholecystectomy, 511 (0.74%) had cirrhosis. In patients without cirrhosis 86.55% underwent a laparoscopic procedure compared with 57.53% in patients with cirrhosis (p < 0.0001). LOS was longer in those with cirrhosis (3 IQR 1-8 vs 1 IQR 1-3 days,p < 0.0001). 90-day re-admission was greater in patients with cirrhosis, 36.79% compared with 14.95% in those without cirrhosis. 90-day case fatality after elective cholecystectomy in patients with and without cirrhosis was 2.79% and 0.43%; and 12.82% and 2.39% following emergency cholecystectomy. This equated to a 3-fold (OR 3.22, IQR 1.72-6.02) and a 4-fold (OR 4.52, IQR 2.46-8.33) increased odds of death at 90-days following elective and emergency cholecystectomy after adjusting for confounders.

CONCLUSION

Patients with cirrhosis undergoing cholecystectomy have an increased 90-day risk of postoperative mortality, which is significantly worse after emergency procedures.

Time trends in the incidence rates of venous thromboembolism following colorectal resection by indication and operative technique

AIM

It is important for patient safety to assess if international changes in perioperative care, such as the focus on venous thromboembolism (VTE) prevention and minimally invasive surgery, have reduced the high post colectomy VTE risks previously reported. This study assesses the impact of changes in perioperative care on VTE risk following colorectal resection.

METHOD

This was a population-based cohort study of colectomy patients in England between 2000 and 2019 using a national database of linked primary (Clinical Practice Research Datalink) and secondary (Hospital Episode Statistics) care data. Within 30 days following colectomy, absolute VTE rates per 1000 person-years and adjusted incidence rate ratios (aIRRs) using Poisson regression for the per year change in VTE risk were calculated.

RESULTS

Of 183 791 patients, 1337 (0.73%) developed 30-day postoperative VTE. Overall, VTE rates reduced over the 20-year study period following elective (relative risk reduction 31.25%, 95% CI 5.69%-49.88%) but not emergency surgery. Similarly, yearly changes in VTE risk reduced following minimally invasive resections (elective benign, aIRR 0.93, 95% CI 0.90-0.97; elective malignant, aIRR 0.94, 95% CI 0.91-0.98; and emergency benign, aIRR 0.96, 95% CI 0.92-1.00) but not following open resections. There was a per year VTE risk increase following open emergency malignant resections (aIRR 1.02, 95% CI 1.00-1.04).

CONCLUSION

Yearly VTE risks reduced following minimally invasive surgeries in the elective setting yet in contrast were static following open elective colectomies, and following emergency malignant resections increased by almost 2% per year. To reduce VTE risk, further efforts are required to implement advances in surgical care for those having emergency and/or open surgery.

The Duration and Magnitude of Postdischarge Venous Thromboembolism Following Colectomy

OBJECTIVE

To assess the impact of current guidelines by reporting weekly postoperative postdischarge venous thromboembolism (VTE) rates.

SUMMARY BACKGROUND DATA

Disparity exists between the postoperative thromboprophylaxis duration colectomy patients receive based on surgical indication, where malignant resections routinely receive 28 days extended thromboprophylaxis into the postdischarge period and benign resections do not.

METHODS

English national cohort study of colectomy patients between 2010 and 2019 using linked primary (Clinical Practice Research Datalink) and secondary (Hospital Episode Statistics) care data. Stratified by admission type and surgical indication, absolute incidence rates (IRs) per 1000 person-years and adjusted incidence rate ratios (aIRRs) for postdischarge VTE were calculated for the first 4 weeks following resection and postdischarge VTE IRs for each postoperative week to 12 weeks postoperative.

RESULTS

Of 104,744 patients, 663 (0.63%) developed postdischarge VTE within 12 weeks after colectomy. Postdischarge VTE IRs per 1000 person-years for the first 4 weeks postoperative were low following elective resections [benign: 20.66, 95% confidence interval (CI): 13.73-31.08; malignant: 28.95, 95% CI: 23.09-36.31] and higher following emergency resections (benign: 47.31, 95% CI: 34.43-65.02; malignant: 107.18, 95% CI: 78.62-146.12). Compared with elective malignant resections, there was no difference in postdischarge VTE risk within 4 weeks following elective benign colectomy (aIRR=0.92, 95% CI: 0.56-1.50). However, postdischarge VTE risks within 4 weeks following emergency resections were significantly greater for benign (aIRR=1.89, 95% CI: 1.22-2.94) and malignant (aIRR=3.13, 95% CI: 2.06-4.76) indications compared with elective malignant colectomy.

CONCLUSIONS

Postdischarge VTE risk within 4 weeks of colectomy is ∼2-fold greater following emergency benign compared with elective malignant resections, suggesting emergency benign colectomy patients may benefit from extended VTE prophylaxis.

Mortality following elective and emergency colectomy in patients with cirrhosis: a population-based cohort study from England

BACKGROUND

Patients with cirrhosis undergoing colectomy have a higher risk of postoperative mortality, but contemporary estimates are lacking and data on associated risk and longer term outcomes are limited. This study aimed to quantify the risk of mortality following colectomy by urgency of surgery and stage of cirrhosis.

DATA SOURCES

Linked primary and secondary-care electronic healthcare data from England were used to identify all patients undergoing colectomy from January 2001 to December 2017. These patients were classified by the absence or presence of cirrhosis and severity. Case fatality rates at 90 days and 1 year were calculated, and cox regression was used to estimate the hazard ratio of postoperative mortality controlling for age, gender and co-morbidity.

RESULTS

Of the total, 36,380 patients undergoing colectomy, 248 (0.7%) had liver cirrhosis, and 70% of those had compensated cirrhosis. Following elective colectomy, 90-day case fatality was 4% in those without cirrhosis, 7% in compensated cirrhosis and 10% in decompensated cirrhosis. Following emergency colectomy, 90-day case fatality was higher; it was 16% in those without cirrhosis, 35% in compensated cirrhosis and 41% in decompensated cirrhosis. This corresponded to an adjusted 2.57 fold (95% CI 1.75-3.76) and 3.43 fold (95% CI 2.02-5.83) increased mortality risk in those with compensated and decompensated cirrhosis, respectively. This higher case fatality in patients with cirrhosis persisted at 1 year.

CONCLUSION

Patients with cirrhosis undergoing emergency colectomy have a higher mortality risk than those undergoing elective colectomy both at 90 days and 1 year. The greatest mortality risk at 90 days was in those with decompensation undergoing emergency surgery.

Improving Venous Thromboembolism Prophylaxis Administration in an Acute Surgical Unit

OBJECTIVES

Venous thromboembolism (VTE) prophylaxis regimes frequently have a wide variation in application. Nepean acute surgical unit was established in 2006 as a novel model for emergency surgical care. As part of the model's rollout, there were several areas of clinical management targeted for improvement, one being VTE prophylaxis compliance. It was decided all patients older than 18 years treated for a variety of acute surgical conditions within the acute surgical unit should be administered routine VTE prophylaxis with heparin and compression stockings. A novel multifaceted intervention was implemented at the time to achieve this goal. The primary aim of this study was to determine VTE prophylaxis administration rates before and after this intervention.

METHODS

A before-after study conducted as a retrospective review of medical records of all patients 18 years or older, having an appendicectomy in 3 periods: Before acute surgical unit (ASU) (November 2004 to October 2006), Early ASU (November 2006 to October 2008), and Established ASU (January 2012 to December 2013). Outcomes were mechanical and pharmacological VTE prophylaxis administration rates for each group.

RESULTS

There were 1149 patients included in the study: Before ASU, 167; Early ASU, 375; and Established ASU, 607. There was a significant stepwise increase in parmacological VTE prophylaxis administration: Before ASU, 54.5%; Early ASU, 74.7%; and Established ASU, 96.9% (Before versus Early: odds ratio [OR], 2.46; 95% confidence interval [CI], 1.68-3.61; P < 0.001; Early versus Established: OR, 10.500; 95% CI, 6.29-17.53; P < 0.001). Mechanical VTE prophylaxis was significantly increased in the established group (Before versus Established: OR, 47.18; 95% CI, 25.61-86.91; P < 0.001).

CONCLUSIONS

There was a significant increase in VTE prophylaxis administration after the implementation of our multifaceted intervention. Allocating a responsible provider dedicated to VTE prophylaxis prescription and compliance checking was a key component to this intervention.

Risk of Postoperative Venous Thromboembolism After Surgery for Colorectal Malignancy: A Systematic Review and Meta-analysis

BACKGROUND

Colorectal cancer has the second highest mortality of any malignancy, and venous thromboembolism is a major postoperative complication.

OBJECTIVE

This study aimed to determine the variation in incidence of venous thromboembolism after colorectal cancer resection.

DATA SOURCES

Following PRISMA and MOOSE guidelines (PROSPERO, ID: CRD42019148828), Medline and Embase databases were searched from database inception to August 2019 including 3 other registered medical databases.

STUDY SELECTION

Two blinded reviewers screened studies with a third reviewer adjudicating any discordance. Eligibility criteria: Patients post colorectal cancer resection aged ≥18 years. Exclusion criteria: Patients undergoing completely endoscopic surgery and those without cancer resection. Selected studies were randomized controlled trials and population-based database/registry cohorts.

MAIN OUTCOME MEASURES

Thirty- and 90-day incidence rates of venous thromboembolism per 1000 person-years following colorectal cancer surgery.

RESULTS

Of 6441 studies retrieved, 28 met inclusion criteria. Eighteen were available for meta-analysis reporting on 539,390 patients. Pooled 30- and 90-day incidence rates of venous thromboembolism following resection were 195 (95% CI, 148-256, I2 99.1%) and 91 (95% CI, 56-146, I2 99.2%) per 1000 person-years. When separated by United Nations Geoscheme Areas, differences in the incidence of postoperative venous thromboembolism were observed with 30- and 90-day pooled rates per 1000 person-years of 284 (95% CI, 238-339) and 121 (95% CI, 82-179) in the Americas and 71 (95% CI, 60-84) and 57 (95% CI, 47-69) in Europe.

LIMITATIONS

A high degree of heterogeneity was observed within meta-analyses attributable to large cohorts minimizing within-study variance.

CONCLUSION

The incidence of venous thromboembolism following colorectal cancer resection is high and remains so more than 1 month after surgery. There is clear disparity between the incidence of venous thromboembolism after colorectal cancer surgery by global region. More robust population studies are required to further investigate these geographical differences to determine valid regional incidence rates of venous thromboembolism following colorectal cancer resection.

Current prevalence of perioperative early venous thromboembolism and risk factors in Chinese adult patients with inguinal hernia (CHAT-1)

Venous thromboembolism (VTE) is an important postoperative complication. We investigated and analyzed the current inguinal hernia treatment methods and occurrence of early postoperative VTE in Chinese adults. This study involved data for patients with inguinal hernia hospitalized in 58 general hospitals in mainland China from January 1st, 2017 to December 31st, 2017. Data were retrospectively analyzed using a questionnaire. After data inputting and cleaning, we stratified and statistically analyzed patients' data using Caprini scores to create a high-, middle-, and low-risk group. A total of 14,322 patients with inguinal hernia were admitted to the 58 participating hospitals. After data collation and cleaning, 13,886 patients (97.0%) met our inclusion and exclusion criteria. The percentages of laparoscopic surgery and open surgery were 51.2% and 48.8%, respectively. 16 VTEs occurred during the hospitalization, accounting for 0.1% of all adverse events (95% confidence interval (CI) 0.11-0.13). The incidence of VTE was 0.2% (95% CI 0.18-0.2) in the high-risk group and 0.02% (95% CI 0.01-0.03) in the middle-risk group, based on Caprini scoring, with a significant difference (p < 0.0001). No VTE occurred in the low-risk group. Only 3,250 (23.4%) patients underwent Caprini risk assessment regarding treatment, with 13.2% receiving any prevention and only 1.2% receiving appropriate prevention. The treatment of inguinal hernia in Chinese adults has progressed somewhat; however, the evaluation and prevention of perioperative VTE was seriously neglected, in our study, and the incidence of postoperative VTE was underestimated postoperatively. Risk factors continue to be inadequately considered.

The risk of venous thromboembolism after surgery for esophagogastric malignancy and the impact of chemotherapy: a population-based cohort study

To define the incidence of postoperative venous thromboembolism (VTE) and effects of chemotherapy in a population undergoing surgery for esophagogastric cancer. This population-based cohort study used linked primary (Clinical Practice Research Datalink) and secondary (Hospital Episode Statistics) care data from England to identify subjects undergoing esophageal or gastric cancer surgery between 1997 and 2014. Exposures included age, comorbidity, smoking, body mass index, and chemotherapy. Crude rates and adjusted hazard ratios (HRs) were calculated for rate of first postoperative VTE using Cox regression models. The cumulative incidence of VTE at 1 and 6 months was estimated accounting for the competing risk of death from any cause. Of the 2,452 patients identified, 1,012 underwent gastrectomy (41.3%) and 1,440 esophagectomy (58.7%). Risk of VTE was highest in the first month, with absolute VTE rates of 114 per 1,000 person-years (95% CI 59.32-219.10) following gastrectomy and 172.73 per 1,000 person-years (95% CI 111.44-267.74) following esophagectomy. Neoadjuvant and adjuvant chemotherapy was associated with a six-fold increased risk of VTE following gastrectomy, HR 6.19 (95% CI 2.49-15.38). Cumulative incidence estimates of VTE at 6 months following gastrectomy in patients receiving no chemotherapy was 1.90% and esophagectomy 2.21%. However, in those receiving both neoadjuvant and adjuvant chemotherapy, cumulative incidence following gastrectomy was 10.47% and esophagectomy, 3.9%. VTE rates are especially high in the first month following surgery for esophageal and gastric cancer. The cumulative incidence of VTE at 6 months is highest in patients treated with chemotherapy. In this category of patients, targeted VTE prophylaxis may prove beneficial during chemotherapy treatment.

Incidence of Venous Thromboembolism Following Major Emergency Abdominal Surgery

BACKGROUND

In a retrospective cohort study, we looked at the incidence and risk factors of developing in-hospital venous thromboembolism (VTE) after major emergency abdominal surgery and the risk factors for developing a venous thrombosis.

METHODS

Data were extracted through medical records from all patients undergoing major emergency abdominal surgery at a Danish University Hospital from 2010 until 2016. The primary outcome was the incidence of venous thrombosis developed in the time from surgery until discharge from hospital. The secondary outcomes were 30-day mortality and postoperative complications. Multivariate logistic analyses were used for confounder control.

RESULTS

In total, 1179 patients who underwent major emergency abdominal surgery during 2010-2016 were included. Thirteen patients developed a postoperative venous thromboembolism (1.1%) while hospitalized. Eight patients developed a pulmonary embolism all verified by CT scan and five patients developed a deep venous thrombosis verified by ultrasound scan. Patients diagnosed with a VTE were significantly longer in hospital with a length of stay of 34 versus 14 days, P < 0.001, and they suffered significantly more surgical complications (69.2% vs. 30.4%, P = 0.007). Thirty-day mortality was equal in patients with and without a venous thrombosis. In a multivariate analysis adjusting for gender, ASA group, BMI, type of surgery, dalteparin dose and treatment with anticoagulants, we found that a dalteparin dose ≥5000 IU was associated with the risk of postoperative surgical complications (odds ratio 1.55, 95% CI 1.11-2.16, P = 0.009).

CONCLUSION

In this study, we found a low incidence of venous thrombosis among patients undergoing major emergency abdominal surgery, comparable to the incidence after elective surgery.

Incidence and risk of venous thromboembolism in patients following appendectomy: a nationwide cohort study

Surgery may lead to poor blood flow and hypercoagulation. Few studies have investigated the incidence of venous thromboembolism (VTE) in Asian patients following appendectomy. We conducted a nationwide cohort study to investigate the risk of VTE in patients who underwent appendectomy compared with those who did not in Taiwan. We studied the entire hospitalized population in Taiwan from 2000 to 2012, with a follow-up period extending to the end of 2013. We identified patients who underwent appendectomy in Taiwan's National Health Insurance Research Database as the appendectomy cohort, and selected a nonappendectomy cohort from the general population that was 4:1 frequency-matched by age (5-year interval), sex, and index year for each appendectomy case. We used Cox models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for symptomatic VTE in the appendectomy cohort for comparison with the nonappendectomy cohort. The appendectomy cohort exhibited a higher incidence of symptomatic VTE than the nonappendectomy cohort (5.90 vs. 3.29 per 10,000 person-years). After adjustment for covariates, a 1.68-fold HR for symptomatic VTE was observed in the appendectomy cohort (95% CI 1.56-1.81). Compared with the nonappendectomy cohort, the patients who underwent open appendectomy had a 1.73-fold increased adjusted HR for symptomatic VTE (95% CI 1.61-1.87). Laparoscopic appendectomy was not significantly associated with symptomatic VTE. An 8.15-fold higher adjusted HR for VTE was observed in patients who underwent appendectomy within the first month after surgery compared with the nonappendectomy cohort. Open appendectomy carried an increased risk of symptomatic VTE. Laparoscopic appendectomy was not significantly associated with symptomatic VTE.