End-stage renal disease increases the risk of mortality after appendectomy

Predicting the complexity of minimally invasive liver resection for hepatocellular carcinoma using machine learning

BACKGROUND

Despite technical advancements, minimally invasive liver surgery (MILS) for hepatocellular carcinoma (HCC) remains challenging. Nonetheless, effective tools to assess MILS complexity are still lacking. Machine learning (ML) models could improve the accuracy of such tools.

METHODS

Patients who underwent curative-intent MILS for HCC were identified using an international database. An XGBoost ML model was developed to predict surgical complexity using clinical and radiological characteristics.

RESULTS

Among 845 patients, 186 (22.0 %) were classified as high-risk patients. In this subgroup, median Charlson Comorbidity Index (CCI) (5.0, IQR 3.0-7.0 vs. 2.0, IQR 2.0-5.0, p < 0.001) and tumor burden score (TBS) (median 4.12, IQR 3.0-5.1 vs. 4.22, IQR 3.2-7.1, p < 0.001) were higher. The model was able to effectively predict complexity of surgery in both the training and testing cohorts with high discriminating power (ROC-AUC: 0.86, 95%CI 0.82-0.89 vs. 0.73, 95%CI 0.65-0.81). The most influential variables were CCI, TBS, BMI, extent of resection, and sex. Patients predicted to have a complex surgery were more likely to develop severe complications (OR 4.77, 95%CI 1.82-13.9, p = 0.002). An easy-to-use calculator was developed.

CONCLUSION

Preoperative ML-prediction of complex MILS for HCC may improve preoperative planning, resource allocation, and patient outcomes.

Acute Appendicitis Treatment Strategies and Mortality Based on Critical Illness on Admission: An Observational Study

Background: Trials have shown non-inferiority of non-operative management (NOM) for appendicitis, although critically ill patients have been often excluded. The purpose of this study is to evaluate surgical versus NOM outcomes in critically ill patients with appendicitis by measuring mortality and hospital length of stay (LOS). Patients and Methods: The Healthcare Cost and Utilization Project's (HCUP) Database was utilized to analyze data from 10 states between 2008 and 2015. All patients with acute appendicitis by International Classification of Diseases, Ninth Revision (ICD-9) codes over the age of 18 were included. Negative binomial and logistic regression were used to determine the association of acute renal failure (ARF), cardiovascular failure (CVF), pulmonary failure (PF), and sepsis by treatment strategy (laparoscopic, open, both, or no surgery) on mortality and hospital LOS. Results: Among 464,123 patients, 67.5%, 23.3%, 8.2%, and 0.8% underwent laparoscopic, open, NOM, or both laparoscopic and open surgery, respectively. Patients who underwent surgery had 58% lower odds of mortality and 34% shorter hospital LOS compared with NOM patients. Patients with ARF, CVF, PF, and sepsis had 102%, 383%, 475%, and 666% higher odds of mortality and a 47%, 46%, 71%, and 163% longer hospital LOS, respectively, compared with patients without these diagnoses on admission. Conclusions: Critical illness on admission increases mortality and hospital LOS. Patients who underwent laparoscopic, and to a lesser extent, open appendectomy had improved mortality compared with those who did not undergo surgery regardless of critical illness status.

Complicated Appendicitis Among Adults With and Without Disabilities: A Cross-Sectional Nationwide Study in South Korea

Objective

Appendicitis is usually diagnosed based on a reliable set of signs and symptoms, and can be effectively treated with surgery, with low morbidity and mortality rates. However, appendicitis is often overlooked in vulnerable populations, including people with disabilities. This study compared 10-year trends of complicated appendicitis between South Koreans with a disability, according to disability severity and type, and those without disabilities

Methods

To identify cases of appendicitis, we used the DRG codes in the National Health Information Database of South Korea. Patients with appendicitis were classified in terms of severity based on the DRG codes. Age-standardized incidence rates were calculated for each year during 2008–2017 according to the presence, type, and severity of the disability. Factors associated with complicated appendicitis were examined by multivariate logistic regression using the most recent data (i.e., 2016–2017).

Results

The incidence of complicated appendicitis was higher in people with disabilities, especially those with severe disabilities (26.9 vs. 11.6%). This difference was particularly marked when considering those with a severe disability (aOR = 1.868, 95% CI:1.511–2.309), internal organ problems (aOR = 10.000, 95% CI:5.365–18.638) or a mental disability (aOR = 2.779, 95% CI:1.563–4.939).

Conclusions

The incidence of complicated appendicitis was higher in people with disability than in those without disability in all years. There was a substantial difference in the incidence of complicated appendicitis between the severe disability and non-disabled groups. Among the various disability types, the incidence of complicated appendicitis was highest for major internal organ problems, followed by intellectual or psychological disabilities. Our findings may be explained by barriers to healthcare access among people with disabilities, particularly those with a severe disability, internal organ problem, or mental disability.

Prediction of Postoperative Complications for Patients of End Stage Renal Disease

End stage renal disease (ESRD) is the last stage of chronic kidney disease that requires dialysis or a kidney transplant to survive. Many studies reported a higher risk of mortality in ESRD patients compared with patients without ESRD. In this paper, we develop a model to predict postoperative complications, major cardiac event, for patients who underwent any type of surgery. We compare several widely-used machine learning models through experiments with our collected data yellow of size 3220, and achieved F1 score of 0.797 with the random forest model. Based on experimental results, we found that features related to operation (e.g., anesthesia time, operation time, crystal, and colloid) have the biggest impact on model performance, and also found the best combination of features. We believe that this study will allow physicians to provide more appropriate therapy to the ESRD patients by providing information on potential postoperative complications.

Can We Improve Prediction of Adverse Surgical Outcomes? Development of a Surgical Complexity Score Using a Novel Machine Learning Technique

BACKGROUND

An optimal method to quantify surgical complexity using patient comorbidities derived from administrative billing data is lacking. We sought to develop a novel, easy-to-use surgical Complexity Score to accurately predict adverse outcomes among patients undergoing elective surgery.

STUDY DESIGN

A novel surgical Complexity Score was developed using 100% Medicare Inpatient and Outpatient Standard Analytic Files (SAFs) from years 2012 to 2016 (n = 1,049,160). Comorbid conditions were entered into a machine learning algorithm to assign weights to maximize the correlation with multiple postoperative outcomes including morbidity, readmission, mortality, and postoperative super-use. Predictive ability was compared against 3 of the most commonly used risk adjustment indices: the Charlson Comorbidity Index (CCI), Elixhauser Comorbidity Index (ECI), and the Centers for Medicare and Medicaid Service's Hierarchical Condition Category (CMS-HCC).

RESULTS

Patients underwent colectomy (12.6%), abdominal aortic aneurysm repair (4.4%), coronary artery bypass grafting (13.0%), total hip replacement (22.0%), total knee replacement (43.0%), or lung resection (5.0%). The Complexity Score had a good to very good predictive ability for all adverse outcomes. The Complexity Score had the highest accuracy in predicting perioperative morbidity (area under the curve [AUC]: 0.868, 95% CI 0.866 to 0.869); this performed better than the CCI (AUC: 0.717, 95% CI 0.715 to 0.719), ECI (AUC: 0.799, 95% CI 0.797 to 0.800), and similar to the CMS-HCC (AUC: 0.862, 95% CI 0.861 to 0.863). Similarly, the Complexity Score outperformed each of the 3 other comorbidity indices in predicting 90-day readmission (AUC: 0.707, 95% CI 0.705 to 0.709), 30-day readmission (AUC: 0.717, 95% CI 0.715 to 0.720), and postoperative super-use (AUC: 0.817, 95% CI 0.814 to 0.820).

CONCLUSIONS

Compared with the most commonly used comorbidity and surgical risk scores, the novel surgical Complexity Score outperformed the CCI, ECI, and CMS-HCC in predicting postoperative morbidity, 30-day readmission, 90-day readmission, and postoperative super-use.

End Stage Renal Disease is Associated with Increased Mortality in Perforated Gastroduodenal Ulcers

Patients with end stage renal disease (ESRD) represent a growing subset of surgical candidates and ESRD status has been associated with increased morbidity and mortality in other operations. Using a national database, we examined outcomes and risk factors for patients presenting with perforated gastroduodenal ulcers undergoing omentopexy. We identified adult and emergent patients with perforated duodenal and gastroduodenal ulcers that underwent omentopexy using the 2005 to 2012 Nationwide Inpatient Sample. We identified patients with ESRD status and assessed comorbidity status using the Elixhauser–van Walraven score. Univariate and multivariable logistic regression analyses were performed. Inpatient mortality was the primary outcome. Six thousand five hundred and twenty-one patients were identified. Median age was 59.0 years, majority were male (55.56%), 79 (1.21%) patients had ESRD, 367 (5.63%) patients died during admission. Multivariable logistic regression showed age (OR 2.71, P < 0.0001), Elixhauser–van Walraven score (OR 2.69, P < 0.0001), and ESRD status (OR 3.88, P < 0.0001) as independent risk factors for mortality. ESRD was associated with increased mortality in patients undergoing omentopexy for perforated gastroduodenal ulcers. Future studies are necessary to identify methods to increase perioperative survival.

Emergency surgery in octogenarians: Outcomes and factors affecting mortality in the general hospital setting

AIM

The Western world has an expanding older population, who are living longer with increasing numbers of comorbidities. In addition, expectations of patients and relatives are increasing. As a general hospital operating in a rural setting, our University Hospital Kerry, Tralee, Ireland, deals with a significant number of emergency presentations to the acute surgical service. The aim of the present study was to examine outcomes for patients in the extremes of age who present requiring emergency surgical procedures.

METHODS

A retrospective review of theater and admission logs was carried out to identify all emergency surgeries from January 2008 to December 2015. All patients aged >80 years at the time of surgery were identified. Details of surgery were recorded, in addition to biochemical and hematological data, use of intensive care unit, length of stay and mortality.

RESULTS

In total, 128 octogenarians underwent an emergency surgery. The average patient age was 84.3 years (range 80-94 years). The commonest procedures were laparotomy (65%, n = 84), repair of strangulated/incarcerated hernia (18%, n = 23) and laparoscopic procedures (16%, n = 21). The 30-day all-cause mortality was 22.6%. On multivariate analysis, American Society of Anesthesia status and intensive care unit utilization predicted mortality (P = 0.04 and 0.05, respectively). A total of 82 patients required intensive care unit admission, with an average length of stay of 4.8 days, using 484 bed days in total.

CONCLUSIONS

Emergency surgery in octogenarians is a significant part of the workload of general surgeons. Poor baseline status is associated with an increased risk of mortality. Emergency surgery in older adults only utilizes a fraction of available intensive care unit resources. Geriatr Gerontol Int 2018; 18: 1211-1214.

A Calculated Risk: Performing Laparoscopic Cholecystectomy for Acute Cholecystitis on Patients with End Stage Renal Disease

End-stage renal disease (ESRD) is a multifactorial disease linked to socioeconomic status and associated with worse surgical outcomes. We explore intraoperative and postoperative outcomes in patients with cholecystitis undergoing laparoscopic cholecystectomy (LC). The Nationwide Inpatient Sample from 2005 to 2012 was used to identify patients undergoing LC for cholecystitis using ICD-9 codes. Outcomes of interest were mortality, common bile duct injury, conversion to open, intraoperative complications, postoperative complications, length of stay (LOS), and total charge. Univariate analysis was performed using t test for continuous variables and chi-squared test for categorical variables. Multivariable models were created that adjusted for age, demographics, year of admission, comorbidities, and presence of ESRD. Of 225,058 patients that underwent LC, 2,115 had ESRD. On univariate analysis, the ESRD cohort had a higher incidence of mortality and complications: intraoperative, mechanical wound, respiratory, cardiovascular, and postoperative infections. ESRD patients had higher median LOS and total charge. Multi-variate analysis showed ESRD as an independent risk factor for mortality, mechanical wound complications, and intraoperative complications. Negative binomial regression analysis showed that ESRD patients had LOS 50.4 per cent longer than non-ESRD patients. Linear regression analysis showed that, after adjustment, ESRD patients had total charge 6.82 per cent higher than non-ESRD patients. In this large retrospective analysis, we find that after adjusting for clinical, socioeconomic, and demographic variables, ESRD is an independent risk factor for increased mortality, intraoperative complications, mechanical wound complications, increased LOS, and cost for patients undergoing LC. Prospective studies exploring risk optimization strategies for patients with ESRD are warranted.

Appendectomy in patients with human immunodeficiency virus: Not as bad as we once thought

BACKGROUND

The number of patients living with human immunodeficiency virus and acquired immunodeficiency syndrome is growing due to advances in antiretroviral therapy. Existing literature on appendectomy within this patient population has been limited by small sample sizes. Therefore, we used a large, multiyear, nationwide database to study this topic comprehensively.

METHODS

Using the Nationwide Inpatient Sample, we identified 338,805 patients between 2005 and 2012 who underwent laparoscopic or open appendectomy for acute appendicitis. Interval appendectomies were excluded. We used multivariable adjusted regression models to test differences between patients with human immunodeficiency virus without acquired immunodeficiency syndrome and a reference group, as well as human immunodeficiency virus with acquired immunodeficiency syndrome and a reference group, with regard to duration of stay, hospital charges, in-hospital complications, and in-hospital mortality. Models were adjusted for patient age, sex, race, insurance, socioeconomic status, Elixhauser comorbidity score, and appendix perforation.

RESULTS

There were 1,291 (0.38%) patients with human immunodeficiency virus, among which 497 (0.15%) patients had acquired immunodeficiency syndrome. In regression analysis, human immunodeficiency virus alone was not associated with adverse outcomes, while acquired immunodeficiency syndrome alone was associated with longer duration of stay (incidence rate ratio 1.40 [1.37-1.57 95% confidence interval], P < .0001), increased total charges (exponentiated coefficient 1.16 [1.10-1.23 95% confidence interval], P < .0001), and increased risk of postoperative infection (odds ratio 2.12 [1.44-3.13 95% confidence interval], P = .0002).

CONCLUSION

Patients with acquired immunodeficiency syndrome who undergo appendectomy for acute appendicitis are subject to longer and more expensive hospital admissions and have greater rates of postoperative infections while patients with human immunodeficiency virus alone are not at risk for adverse outcomes.

Emergency general surgery in the geriatric patient

BACKGROUND

Emergency general surgery in the elderly is a particular challenge to the surgeon in charge of their care. The aim was to review contemporary aspects of managing elderly patients needing emergency general surgery and possible alterations to their pathways of care.

METHODS

This was a narrative review based on a PubMed/MEDLINE literature search up until 15 September 2015 for publications relevant to emergency general surgery in the geriatric patient.

RESULTS

The number of patients presenting as an emergency with a general surgical condition increases with age. Up to one-quarter of all emergency admissions to hospital may be for general surgical conditions. Elderly patients are a particular challenge owing to added co-morbidity, use of drugs and risk of poor outcome. Frailty is an important potential risk factor, but difficult to monitor or manage in the emergency setting. Risk scores are not available universally. Outcomes are usually severalfold worse than after elective surgery, in terms of both higher morbidity and increased mortality. A care bundle including early diagnosis, resuscitation and organ system monitoring may benefit the elderly in particular. Communication with the patient and relatives throughout the care pathway is essential, as indications for surgery, level of care and likely outcomes may evolve. Ethical issues should also be addressed at every step on the pathway of care.

CONCLUSION

Emergency general surgery in the geriatric patient needs a tailored approach to improve outcomes and avoid futile care. Although some high-quality studies exist in related fields, the overall evidence base informing perioperative acute care for the elderly remains limited.