Influence of obesity on complications and costs after intestinal surgery

doi:10.1016/j.amjsurg.2012.01.013

The American Journal of Surgery

Volume 204, Issue 4, October 2012, Pages 434-440

Presented at the 35th annual meeting of the Association of VA Surgeons, Irvine, CA, April 10–12, 2011.

https://doi.org/10.1016/j.amjsurg.2012.01.013 Get rights and content

Abstract

Background

Obesity is a risk factor for many comorbid conditions that increase the cost of health care. We sought to examine the effect of obesity on surgical complications and cost in a group of patients undergoing intestinal surgery.

Methods

Using the Veterans Affairs Surgical Quality Improvement Program (VASQIP), which includes clinical data abstracted from medical records for Veterans Affairs (VA) surgical patients, and the VA Decision Support System, which provides the costs of individual patient encounters on the basis of relative values assigned to intermediate products, we examined surgical complications and costs of care in 4,881 patients undergoing intestinal surgery in 2006. Patients were classified into 4 groups based on body mass index (BMI): malnourished (<18), normal weight (18–30), obesity class I to II (30–40), and obesity class III (>40). Patient endpoints included the occurrence of any complication and surgical costs incurred within 30 days of surgery. Endpoints were compared across the 4 BMI categories in unadjusted analyses and risk-adjusted analyses and hospital-level variation using multivariable models.

Results

After controlling for patient risk factors and hospital-level variation, patients in obesity class I to II were 1.21 times more likely to have any complication and patients in obesity class III were 1.41 times more likely to have any complication when compared with normal-weight patients. Similarly, patients in obesity class I to II were 1.44 times more likely to develop a wound complication compared with normal-weight patients, and patients in class III were 1.84 times more likely to develop a wound complication and 1.55 times more likely to develop a respiratory complication compared with normal-weight patients. In contrast, costs were greatest for malnourished patients at $45,000 compared with normal-weight patients at $37,000. However, after controlling for patient risk factors and variation in costs attributable to the admitting hospital, there were no significant cost differences between the 4 BMI categories.

Conclusions

Obesity leads to increased wound and respiratory complications in intestinal surgery. Nevertheless, obesity alone is not an independent risk factor for increased costs in intestinal surgery.

Section snippets

Methods

To determine the effects of obesity on complications after intestinal surgery, we used the VASQIP, which included 118 acute care Veterans Affairs (VA) hospitals that performed inpatient surgery during the 2006 fiscal year and are represented in the VASQIP.2, 3 VASQIP collects a wide range of preoperative risks factors, information about the operative procedures and anesthesia, and postoperative complications and mortality. Data are abstracted from each VA medical center for patients undergoing

Results

Table 1 shows characteristics of the 4,881 patients evaluated in this study. Overall, 69% were categorized as having a normal BMI (BMI 18–30), whereas malnourished patients (BMI <18) represented 2%, obesity class I to II (BMI 30–40) 25%, and obesity class III (BMI >40) 3% (Table 1). Unadjusted analysis (Table 2) suggested a higher complication rate in the higher BMI categories although this result was not statistically significant (P = .06). Of the 4 categories, patients in obesity class III

Comments

Multiple studies have shown that obesity leads to an increased operative time and increased intraoperative blood loss. Khan et al⁸ analyzed 586 patients undergoing pancreatoduodenectomy and showed that operating time was significantly higher as BMI increased. Specifically, patients with a BMI greater than 35 had an average operating time of 380 minutes compared with 342 minutes for patients with a BMI less than 25. There was also increased blood loss, with an 800-mL average blood loss for

Acknowledgments

The authors would also like to acknowledge the VA Surgical Quality Data Use Group for its role as scientific advisers and for the critical review of data use and analysis presented in this manuscript.

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2021, American Journal of Surgery
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In the United States, the prevalence of obesity is now greater than 40%, with rates of severe obesity - defined as a BMI of at least 40 kg/m2 - around 9%.2 Obese patients are reported to have worse intraoperative and postoperative surgical outcomes, including longer operative times,3,4 increased rates of surgical site infection,5,6 increased rates of wound dehiscence,7 and higher chances of postoperative mortality than non-obese patients.8 Obesity significantly affects colorectal surgeons, where the most common indications for a colorectal resection – cancer, diverticulitis, and inflammatory bowel disease (IBD) – are all more prevalent in obese patients,9–11 and have been associated with increased costs12 and increased rates of conversion from laparoscopy.13
Operating on obese patients can increase case complexity and result in worse outcomes. We described the incremental impact of BMI on morbidity and outcomes of colorectal operations and whether laparoscopic and robotic(MIS) approaches mitigate this morbidity differently.
A retrospective cohort of patients undergoing elective colorectal operations in SCOAP was created to examine the association of increasing BMI on surgical outcomes. Additionally, multivariable logistic regression models were constructed.
From 2011 to 2019, 22,863 elective colorectal operations (mean age 62, 55% female) were performed at 42 hospitals. Patients had BMI≥30 in 7576(33%) and BMI≥40 in 1180(5%) of operations. After risk adjustment, BMI≥40 was associated with increased conversions(OR1.57,95%CI1.26–1.96), increased combined adverse events(CAE)(OR1.32,95%CI1.15–1.52), and death(OR2.24, 95%CI1.41–3.55)(all p < 0.01). MIS approaches were each associated with lower CAE(lap OR0.49,95%CI0.46–0.53; robot OR0.42,95%CI0.37–0.47), and death(lap OR0.24,95%CI0.18–0.33; robot OR0.18,95%CI0.10–0.35)(all p < 0.01).
Severe obesity is associated with increased conversion rates and worse short-term outcomes after colorectal surgery, though this trend is partially mitigated with a minimally invasive approach. These findings support the broad application of MIS for colorectal operations in obese patients.
Economic Cost Analysis Related to Complications in General and Digestive Surgery
2018, Cirugia Espanola
El objetivo es analizar el impacto en costes económicos y estancias de las complicaciones quirúrgicas.
Incluimos 5.822 registros del CMBD (2014-2015). Realizamos análisis descriptivo, univariante y multivariante, evaluando asociación entre complicaciones, grado Clavien-Dindo y vacaciones con estancias y costes económicos (modelo de costes totales agregados por GRD).
El coste medio por estancia es de 676,71€, y de 4.309,02€ por episodio. Presentaron complicación 639 (11%). 203 ingresos en UCI, 134 reintervenciones, 243 reingresos y 66 fallecimientos (1,1%). Las complicaciones generan mayor estancia (20,08 vs 5,48 días) y coste (11.670,31€ vs 3.354,12€), siendo las infecciosas las más frecuentes y las respiratorias las más costosas (20.428,53€), conjuntamente con ingreso en UCI. El grado de Clavien-Dindo se correlaciona con el incremento de estancias y costes (excepto grado v). En vacaciones aumentan complicaciones y estancias, pero sus costes no varían respecto a no vacaciones.
The aim was to assess the impact on economic costs and length of stay (LOS) of postoperative complications.
5,822 records from BMDS (2014-2015) are included. A descriptive, univariate and multivariate study evaluated the correlation between complications, Clavien-Dindo grade and vacation periods with LOS and economic costs, based on a full-cost model, aggregated by DRG.
Mean cost per stay was €676.71, and €4,309.02 per episode. Complications appeared in 639 patients (11%). Admission to ICU was required in 203 patients, re-operation in 134 and re-admission in 243, while 66 patients died (1.1%). Complications caused significantly longer LOS (20.08 vs 5.48 days) and higher economic cost (€11,670.31 vs €3,354.12); infectious complications were the most frequent and respiratory the most expensive (€20,428.53), together with ICU admission (€20,242.66). Clavien-Dindo grade correlated with greater LOS and costs (except grade v). During vacation periods, complications and LOS are increased, but costs of these complications and LOS did not differ significantly from complications detected in non-vacation periods.
Surgical and Functional Outcomes Following Buried Penis Repair With Limited Panniculectomy and Split-thickness Skin Graft
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In other surgical populations, obesity has similarly been found to be linked to increased risk of complications. Obesity has been linked to wound complications and prolonged hospital stay in ovarian cancer patients, an increased risk of overall surgical morbidity in endometrial cancer patients, an increased risk of developing a hospital-acquired condition in adult spinal deformity patients, and an increased risk of wound and respiratory complications in intestinal surgery patients.12-15 Furthermore, a BMI >40 kg/m2 has been linked to an increased risk of morbidity due to wound infections, thromboembolism, and renal complications in vascular surgery patients and increased early major adverse clinical outcomes in cardiac surgery patients.16,17
To report surgical and functional outcomes of buried penis surgery.
Outcomes following buried penis surgery at the University of Washington were assessed from June 1, 2005 to June 1, 2016. Patient demographic and surgical data were abstracted from a retrospective chart review. All patients were attempted to be contacted by phone for long-term follow-up. Uni- and multivariate analysis was performed to evaluate for association with any complication.
A total of 42 men underwent buried penis repair surgery (mean short-term follow-up 8.1 months). There was an overall 33% 90-day complication rate (21 events). In univariate analysis, body mass index (BMI; P = .02) and no history of gastric bypass (P = .03) were significant predictors of any complication. In multivariate analysis, only BMI remained significant (odds ratio 1.1 for each increase in unit of BMI, 95% confidence interval 1.01-1.27). Twenty-seven patients were reached for long-term follow-up (mean 39 months). Patients reported improvements in every functional domain that was assessed. Of the patients, 85% reported they would undergo buried penis surgery again, 74% that surgery led to a positive change in their lives, and 85% that the surgery had remained a long-term success.
Surgical correction of buried penis with penile split-thickness skin graft and limited panniculectomy is well tolerated and results in functional, long-term improvements. BMI is associated with an increased likelihood of a complication following surgery.
Influence of high body mass index on mortality and infectious outcomes in patients who underwent open gastrointestinal surgery: A meta-analysis
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Considering these factors, high-BMI patients tended to have higher risks of infectious outcomes following open gastrointestinal surgery. Our results indicated that high-BMI patients had significantly increased risks of SSI and pulmonary infection, which is basically in accordance with tradition.22,37,38 Heterogeneity was high in SSI, which was probably caused by different SSI types and follow-up compliance, because according to the Centers for Disease Control and Prevention,14 SSI includes superficial, subcutaneous cellular tissue, and organ space infections.
The influence of high body mass index (BMI) on mortality and infectious outcomes of patients following open gastrointestinal surgery was unclear. This meta-analysis aimed to resolve this controversy.
PubMed and EMBASE were searched by 2 researchers. High and normal BMIs were defined as ≥25 and 18.5-24.99, respectively. Odds ratios (ORs) were calculated to compare the pooled effect sizes. The primary outcome was mortality. The secondary outcome was infectious outcomes, including surgical site, pulmonary infections, and urinary tract infections.
Eleven eligible articles with 51,307 patients total were included. Compared with normal BMIs, high BMIs did not increase the risk of mortality (OR, 0.78; 95% confidence interval [CI], 0.58-1.06; P = .12). The secondary outcome indicated a significantly higher risk of infectious outcomes in high-BMI patients (OR, 1.34; 95% CI; 1.13-1.58; P = .0007). Among high-BMI patients, the risks of surgical site infections (OR, 1.75; 95% CI, 1.33-2.3; P < .0001) and pulmonary infections (OR, 1.2; 95% CI, 1.02-1.40; P = .03) increased significantly; urinary tract infections (OR, 1.10; 95% CI, 0.92-1.31; P = .30) did not show statistical difference.
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Preoperative risk assessment has become an integral component of adult surgery. For example, both obese adults and those with elevated American Society of Anesthesiology (ASA) class have higher risk for perioperative complications [1–3]. Obesity also correlates with postoperative morbidity in adult cardiac transplant patients.
Preoperative risk assessment is standard in adult surgery, but often these risk assessments cannot be applied to children. Previous studies emphasize the differences between pediatric and adult populations and variability by surgical procedure types.
We investigated preoperative risk factors for several outcomes in children undergoing major urologic surgery using the National Surgical Quality Improvement Program (NSQIP) Pediatric.
A cohort of 2–18-year-old children who underwent major urologic surgery was identified by Current Procedure Terminology (CPT) codes in the 2012–2013 NSQIP-Pediatric. The NSQIP-Pediatric prospectively collects standardized and validated data from 61 sites on preoperative, operative, and 30-day postoperative variables. Urologic surgeries involving dissection of the peritoneal or extraperitoneal space were included. Patients undergoing pure genitourinary surgery were analyzed separately from those with bowel involvement to improve homogeneity. Postoperative outcomes including hospital length of stay and 30-day infective complications, non-infective complications, unplanned reoperation and readmissions were evaluated by fitting multivariable logistic regression models.
A total of 2601 patients were identified, of whom 399 (15.3%) underwent bowel-involved surgery and 2202 (84.7%) underwent pure genitourinary surgery. Patients in the bowel-involved group were significantly older with more comorbidity. Postoperative complications, unplanned return to operating room, hospital length of stay and readmission rates were all significantly worse in the bowel-involved group. In the pure genitourinary group, older age and white race improved some outcomes, while American Society of Anesthesia (ASA) class ≥ 3, total operation time, obesity, pulmonary risk factors, preoperative renal disease, developmental delay, structural central nervous system abnormality, and supplemental nutrition independently predicted at least one negative outcome (Table).
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This study aims to describe the magnitude of hospital costs among patients undergoing elective colectomy, cholecystectomy, and pancreatectomy, determine whether these costs relate as expected to duration of care, patient case-mix severity and comorbidities, and whether risk-adjusted costs vary significantly by hospital. Correctly estimating the cost of production of surgical care may help decision makers design mechanisms to improve the efficiency of surgical care.
Patient data from 202 hospitals in the ACS-NSQIP were linked to Medicare inpatient claims. Patient charges were mapped to cost center cost-to-charge ratios in the Medicare cost reports to estimate costs. The association of patient case-mix severity and comorbidities with cost was analyzed using mixed effects multivariate regression. Cost variation among hospitals was quantified by estimating risk-adjusted hospital cost ratios and 95% confidence intervals from the mixed effects multivariate regression.
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: Supported by a VA HSR&D merit review grant (IIR-07-151-1).

: The opinions expressed are those of the authors and not necessarily those of the Department of Veterans Affairs or the US Government.

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Clinical scienceInfluence of obesity on complications and costs after intestinal surgery

Abstract

Background

Methods

Results

Conclusions

Section snippets

Methods

Results

Comments

Acknowledgments

Am J Surg

J Am Coll Surg

J Gastrointest Surg

J Am Coll Surg

Obstet Gynecol

J Gastrointest Surg

The obesity epidemic in the United States-gender, age, socioeconomic, racial/ethnic, and geographic characteristics: a systematic review and Meta-regression analysis

Epidemiol Rev

The Department of Veteran's Affairs NSQIP: the first national, validated, outcome-based, risk-adjusted, and peer-controlled program for the measurement and enhancement of the quality of surgical care

Ann Surg

The use of the transition cost accounting system in health services research

Cost Eff Resour Alloc

Clinical science
Influence of obesity on complications and costs after intestinal surgery