Impact of super obesity on perioperative outcomes after hepatectomy: The weight of the risk

Association of High BMI With Morbidity and Mortality in Common Emergency General Surgery Procedures

INTRODUCTION

Emergency general surgery (EGS) patients are at increased risk for postoperative morbidity and mortality. Obesity is a risk factor for poor outcomes in this population. Our study aimed to explore the association of body mass index (BMI) with postoperative outcomes in patients requiring common EGS procedures.

METHODS

A retrospective review of the 2018-2020 National Surgical Quality Improvement Program database identified patients undergoing four common EGS procedures: large bowel resection, small bowel resection, cholecystectomy, and appendectomy. Patients were classified by BMI: normal weight (18.5-24.9 kg/m2), obesity classes I (30-34.9 kg/m2), II (35-39.9 kg/m2), III (40-49.9 kg/m2), and IV (≥50 kg/m2). Main outcomes of interest were major adverse event (MAE) and mortality.

RESULTS

From 2018 to 2020, a total of 82,540 patients underwent one of four common EGS procedures. On unadjusted analysis, obesity class IV had higher mortality rates compared to classes I-III (6.2% vs 3.1%, P < 0.001). Patients in obesity classes I-III had lower odds of MAE and death relative to those of normal weight. Compared to other patients with obesity, those in obesity class IV were at increased risk of MAE (odds ratio 1.27; 95% confidence interval 1.13-1.44) and death (odds ratio 1.69; 95% confidence interval 1.34-2.13).

CONCLUSIONS

Patients with varying degrees of obesity have different risk profiles following common EGS procedures. While patients in lower obesity classes had reduced odds of adverse outcomes, those with BMI ≥50 kg/m2 were particularly at greater risk for postoperative morbidity and mortality. This vulnerable population warrants further investigation and increased vigilance to ensure high-quality care.

Stratifying risk of failure to achieve textbook outcomes among patients undergoing hepatectomy for hepatocellular carcinoma: A multicenter score validation study

BACKGROUND AND AIMS

The concept of textbook outcomes (TOs) has gained increased attention as a critical metric to assess the quality and success of outcomes following complex surgery. A simple yet effective scoring system was developed and validated to predict risk of not achieving textbook outcomes (non-TOs) following hepatectomy for hepatocellular carcinoma (HCC).

METHODS

Using a multicenter prospectively collected database, risk factors associated with non-TO among patients who underwent hepatectomy for HCC were identified. A predictive scoring system based on factors identified from multivariate regression analysis was used to risk stratify patients relative to non-TO. The score was developed using 70 % of the overall cohort and validated in the remaining 30 %.

RESULTS

Among 3681 patients, 1458 (39.6 %) failied to experience a TO. Based on the derivation cohort, obesity, American Society of Anaesthesiologists score(ASA score), Child-Pugh grade, tumor size, and extent of hepatectomy were identified as independent predictors of non-TO. The scoring system ranged from 0 to 10 points. Patients were categorized into low (0-3 points), intermediate (4-6 points), and high risk (7-10 points) of non-TO. In the validation cohort, the predicted risk of developing non-TOs was 39.0 %, which closely matched the observed risk of 39.9 %. There were no differences among the predicted and observed risks within the different risk categories.

CONCLUSIONS

A novel scoring system was able to predict risk of non-TO accurately following hepatectomy for HCC. The score may enable early identification of individuals at risk of adverse outcomes and inform surgical decision-making, and quality improvement initiatives.

Impact of body mass index on perioperative outcomes of laparoscopic major hepatectomies

BACKGROUND

Data on the effect of body mass index on laparoscopic liver resections are conflicting. We performed this study to investigate the association between body mass index and postoperative outcomes after laparoscopic major hepatectomies.

METHODS

This is a retrospective review of 4,348 laparoscopic major hepatectomies at 58 centers between 2005 and 2021, of which 3,383 met the study inclusion criteria. Concomitant major operations, vascular resections, and previous liver resections were excluded. Associations between body mass index and perioperative outcomes were analyzed using restricted cubic splines. Modeled effect sizes were visually rendered and summarized.

RESULTS

A total of 1,810 patients (53.5%) had normal weight, whereas 1,057 (31.2%) were overweight and 392 (11.6%) were obese. One hundred and twenty-four patients (3.6%) were underweight. Most perioperative outcomes showed a linear worsening trend with increasing body mass index. There was a statistically significant increase in open conversion rate (16.3%, 10.8%, 9.2%, and 5.6%, P < .001), longer operation time (320 vs 305 vs 300 and 266 minutes, P < .001), increasing blood loss (300 vs 300 vs 295 vs 250 mL, P = .022), and higher postoperative morbidity (33.4% vs 26.3% vs 25.0% vs 25.0%, P = .009) in obese, overweight, normal weight, and underweight patients, respectively (P < .001). However, postoperative major morbidity demonstrated a "U"-shaped association with body mass index, whereby the highest major morbidity rates were observed in underweight and obese patients.

CONCLUSION

Laparoscopic major hepatectomy was associated with poorer outcomes with increasing body mass index for most perioperative outcome measures.

Impact of body mass index on the difficulty and outcomes of laparoscopic left lateral sectionectomy

INTRODUCTION

Currently, the impact of body mass index (BMI) on the outcomes of laparoscopic liver resections (LLR) is poorly defined. This study attempts to evaluate the impact of BMI on the peri-operative outcomes following laparoscopic left lateral sectionectomy (L-LLS).

METHODS

A retrospective analysis of 2183 patients who underwent pure L-LLS at 59 international centers between 2004 and 2021 was performed. Associations between BMI and selected peri-operative outcomes were analyzed using restricted cubic splines.

RESULTS

A BMI of >27kg/m2 was associated with increased in blood loss (Mean difference (MD) 21 mls, 95% CI 5-36), open conversions (Relative risk (RR) 1.13, 95% CI 1.03-1.25), operative time (MD 11 min, 95% CI 6-16), use of Pringles maneuver (RR 1.15, 95% CI 1.06-1.26) and reductions in length of stay (MD -0.2 days, 95% CI -0.3 to -0.1). The magnitude of these differences increased with each unit increase in BMI. However, there was a "U" shaped association between BMI and morbidity with the highest complication rates observed in underweight and obese patients.

CONCLUSION

Increasing BMI resulted in increasing difficulty of L-LLS. Consideration should be given to its incorporation in future difficulty scoring systems in laparoscopic liver resections.

[Obesity from the Perspective of Surgical Oncology]

Up to 40% of all adults worldwide are overweight or obese. Besides the established obesity-related comorbidities, such as type 2 diabetes mellitus, hypertension or NAFLD (non-alcoholic fatty liver disease), the focus of interest is shifting towards the influence of increased body weight as a risk factor for the development of malignant diseases. For more than 20 different types of malignancies, interactions between increased body weight and cancer risk have been established. Pathophysiological influences of obesity on carcinogenesis are diverse, including factors such as chronic inflammation, hyperinsulinaemia and insulin resistance, various changes in growth factor and changes in sex hormones. In cohorts of visceral oncology patients, malignancies such as colorectal carcinomas, hepatocellular carcinomas, adenocarcinomas of the pancreas, oesophageal and gastric carcinomas are also linked to an increased disease risk with increasing body weight. Since obesity must be considered a preventable or at least treatable cause of cancer, this review examines the influence of obesity in the field of visceral oncology, examining the effects of obesity on tumour prevalence, prevention and diagnostic testing, as well as its influence on treatment and prognosis. Furthermore, this review explores the current evidence on the influence of bariatric surgery on the prevalence of these obesity associated tumours. For example, in the case of colorectal carcinomas, the evidence base following bariatric surgery is mixed, painting an inhomogeneous picture. On the other hand, significantly lower prevalence of pancreatic adenocarcinoma and hepatocellular carcinomas is to be noted. The latter effect can be explained by the decrease in non-alcoholic fatty liver disease (NAFLD) associated with weight loss. Despite the justified concern that bariatric procedures (especially gastric sleeve resection) lead to increased prevalence of malignancies of the oesophageal junction, the currently available epidemiological data does not seem to identify a relevant increase in the incidence of these malignancies.

Operative and long-term oncologic outcomes of laparoscopic versus open major liver resection in patients with a high body mass index (> 25 kg/m2): a propensity score matching analysis

BACKGROUND

With the recent rapid increase in the prevalence of obesity, the number of obese patients requiring liver resection, including laparoscopy, has increased. Accordingly, evaluating the outcome of laparoscopic liver resection in obese patients is increasingly important. This study aimed to compare the safety and feasibility of laparoscopic major liver resection (LMR) and open major liver resection (OMR) in patients with a high body mass index (BMI > 25.0 kg/m²).

METHODS

We reviewed 521 patients with high BMI (> 25.0 kg/m²) who underwent major liver resection for various indications between January 2009 and November 2018 at Asan Medical Center. We performed 1:1 propensity score matching of the LMR and OMR groups, with 120 patients subsequently included in each group.

RESULTS

LMR was associated with lower blood loss and shorter postoperative hospital stays (p < 0.001). Although there was no significant difference in overall complications (p = 0.080), non-liver-specific complications were observed less frequently after LMR (p = 0.025). American Society of Anesthesiologists class > II, BMI > 30 kg/m², and malignancy were independent predictors of morbidity. In a subgroup analysis of patients with hepatocellular carcinoma, there was no significant difference between the two groups in overall survival (hazard ratio 0.225; 95% confidence interval 0.049-1.047; p = 0.057) and recurrence-free survival (hazard ratio 0.761; 95% confidence interval 0.394-1.417; p = 0.417).

CONCLUSIONS

Obesity should not be considered a contraindication for major liver resection using a laparoscopic approach; however, when applying this approach for resecting malignancies in patients with a BMI > 30 kg/m² and comorbid diseases, special attention should be paid to the possibility of complications.

Perioperative Challenges in Patients Transplanted with Livers from Extreme Obese Donors

The combination of rising rates of obesity and the shortage of deceased donor livers have forced the consideration of marginal liver donors in terms of body mass index (BMI) for liver transplantation (LT). To date, there are still conflicting data on the impact of donor obesity on post-LT outcomes. We analyzed all patients undergoing LT alone in the United States (US) from October 2005 through December 2019 using the United Network of Organ Sharing (UNOS) data set. We categorized donor BMI >40 kg/m² as extremely obese (EO). Primary endpoints included 30-day perioperative mortality and early graft loss (EGL) within 7 days. A subgroup analysis was performed for the EO donor group to assess how macrovesicular steatosis (MaS) >30% affects 30-day mortality and EGL within 7 days. A total of 72,616 patients underwent LT during the study period. The 30-day perioperative mortality was significantly higher in the EO donor group (P = 0.02). On multivariate analysis, recipients undergoing LT with EO donors had a 38% higher 30-day mortality risk (odds ratio [OR], 1.38; 95% confidence interval [CI], 1.21-1.69) and 53% increased risk of EGL (OR, 1.53; 95% CI, 1.22-1.90). MaS >30% was independently associated with a 2-fold increased risk of 30-day mortality (P = 0.003) and 3.5-fold increased risk of EGL within 7 days (P < 0.001). The impact of MaS >30% in EGL was 2-fold for all patients transplanted during the study period compared with 3.5-fold in the EO donor group. There is an increased risk of EGL and 30-day perioperative mortality in recipients transplanted with EO donors. Future studies are warranted in morbid and super obese donors to assess the possible effect of obesity-related proinflammatory factors in EGL.

Hepatic Steatosis is Associated with an Increased Risk of Postoperative Infections and Perioperative Transfusion Requirements in Patients Undergoing Hepatectomy

BACKGROUND

To determine the impact of hepatic steatosis on perioperative outcomes of patients undergoing hepatectomy.

METHODS

We analyzed all hepatectomy patients with normal and fatty liver texture, between 2014 and 2018 using NSQIP. Main endpoints included perioperative transfusions (within 72 h) and infectious complications.

RESULTS

A total of 8,237 patients underwent hepatectomy during the study period. The overall rate of fatty liver texture (FLG) was 31% (2,557). Operative duration was significantly longer; inflow occlusion was more common (Pringle maneuver), and the need of transfusions was significantly higher in the FLG compared to the normal liver group (NLG) (p =  < 0.001). On multivariate analysis, patients in the FLG had increased risk of developing infectious complications (OR 1.22 [95%IC 1.05-1.41]) and transfusion requirements within 72 h after hepatectomy (OR 1.43 [95% CI 1.24-1.63]).

CONCLUSIONS

Hepatic steatosis is an independent risk factor for the development of infectious complications and increased perioperative transfusion requirements in patients undergoing hepatectomy. Those requiring transfusions within 72 h had also an increased risk of infections after hepatectomy.

Obesity is an Independent Risk Factor for Mortality in Otherwise Healthy Patients After Hepatectomy

BACKGROUND

Obesity is often associated with comorbidities that limit remnant liver recovery after hepatectomy. The extent to which obesity, in the absence of comorbidities, impacts surgical risk after hepatectomy is unknown. We hypothesized that an obese population without major comorbidities would not be at increased risk of adverse outcomes after hepatectomies.

METHODS

We performed a retrospective analysis identifying patients who underwent hepatectomies from the American College of Surgeons National Surgical Quality Improvement Program data set 2005-2017. Outcomes of interest included the following: mortality, any morbidity, critical care complications, and failure to discharge home. Body mass index (BMI) was the primary variable of interest, grouped as ≥35 and <35 based on bivariate tests of associations with candidate cut-off points. In attempt to isolate the effect of obesity on outcomes among patients "without major comorbidities" (WOC), we included patients without diabetes, chronic obstructive pulmonary disease, renal insufficiency, and nonsmokers; remaining patients were grouped as "with major comorbidities" (WC). Multivariable logistic regression was used to test whether obesity is independently associated with the outcomes of interest after adjustment for other covariates.

RESULTS

A total of 36,396 patients were included. There were 13,754 patients in the WOC group and 22,642 in the WC group. Among patients in the WOC group, the adjusted odds of mortality were 2.2 times higher for patients with a BMI ≥35 versus a BMI <35. Among the patients in the WC group, a BMI ≥35 was not a statistically significant predictor of mortality after adjustment for other covariates. Obese patients had increased odds of each outcome among the WOC group.

CONCLUSIONS

Our hypothesis was refuted by these data. In fact, the adverse effect of obesity was more evident among healthy patients.

Influence of obesity on in-hospital and postoperative outcomes of hepatic resection for malignancy: a 10-year retrospective analysis from the US National Inpatient Sample

OBJECTIVES

The influence of obesity on the outcomes of curative liver resection for malignancies remains controversial. We aimed to compare the in-hospital outcomes of liver resection for malignancy between obese and non-obese patients.

DESIGN

This was a population-based, retrospective, observational study using data from the Nationwide Inpatient Sample (NIS), the largest all-payer US inpatient care database.

SETTING

Hospitalisations of adults ≥18 years old with diagnoses of primary hepatobiliary malignancy or secondary malignant neoplasms of liver in the USA were identified from the NIS database between 2005 and 2014.

PARTICIPANTS

Data of 18 398 patients ≥18 years old and underwent liver resection without pancreatic resection in the NIS were extracted. All included subjects had primary hepatobiliary malignancy or secondary malignant neoplasms of the liver. Patients were divided into obese and non-obese groups. These groups were compared with respect to postoperative complications, length of hospital stay and hospital cost according to surgical extent and approach.

INTERVENTIONS

Patients were undergoing lobectomy of liver or partial hepatectomy.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary endpoints of this study were postoperative complications, length of hospital stay and hospital cost.

RESULTS

After adjustment, obese patients were significantly more likely to experience postoperative complications than were non-obese patients (adjusted OR 1.25, 95% CI 1.10 to 1.42), regardless of whether lobectomy or partial hepatectomy was performed. Furthermore, obesity was significantly associated with increased risk of postoperative complications in patients who underwent open liver resection, but not laparoscopic resection. No significant difference was observed in length of hospital stay or total hospital costs between obese and non-obese patients.

CONCLUSIONS

After adjustment for preoperative comorbidities and other potential confounders, obesity is significantly associated with greater risk of complications in patients undergoing open liver resection for malignancy, but not laparoscopic resection.