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High volume bariatric centres may benefit patients with morbid obesity undergoing general surgery

Updated: Nov 5, 2021

Patients with morbid obesity undergoing general surgery may benefit from having general surgery at a high volume bariatric centres, according to researchers from the Medical College of Wisconsin. The believe that the benefits come from the familiarity with the management principles required to minimise the postoperative risk associated with morbid obesity and improve patient outcomes. The findings were featured in the paper, ‘The Effect of Bariatric Surgery Volume on General Surgery Outcomes for Morbidly Obese Patients’, was published in the Journal of Obesity.

The authors noted that previous research has demonstrated that patients with morbid obesity have an increased risk of perioperative complications vs patient with BMI<25. In addition, bariatric surgery performed at high volume centres decreases the length of stay, cost, and morbidity and mortality. They hypothesised that patients having any general surgical procedure, would have decreased mortality and morbidity at centres performing high volumes of bariatric surgery, as the hospital facility and staff are experienced in the surgical care of morbidly obese patients.

For their study, the investigators used data from the 2016 National Inpatient Sample (NIS) to evaluate complication rates in patients with morbid obesity following traditionally, low-risk general surgery procedures, namely, non-elective or elective laparoscopic cholecystectomy, laparoscopic or open ventral hernia repair with or without mesh, and non-elective laparoscopic or open appendectomy. The primary outcomes were post-operative complications, mortality and length of stay.

In total there were 3,867 cases at high volume bariatric hospitals (HVBH) and 10,161 cases at low volume bariatric hospitals (LVBH). The HVBH patients were younger (50.5 years vs. 51.2 years, p=0.03), with a shorter length of stay (4.85 days vs. 5.39 days, p<0.0001). Patients at LVBH were still more likely to have bowel obstructions (p=0.012), pulmonary failure (<0.0001), postoperative infection (0.005), wound disruption (p=0.03) or any postoperative complication (p<0.0001).


In the study cohort, 942 patients underwent elective laparoscopic cholecystectomy at HVBH (weighted n=4,710) and 823 patients underwent elective laparoscopic cholecystectomy at LVBH (weighted n=4,115). The outcomes revealed that patients at LVBH had higher rates of pulmonary failure (p<0.0001), any complication (p=0.04) and a significantly increased risk of postoperative mortality (p=0.05). In the study cohort, 1,047 patients underwent nonelective laparoscopic cholecystectomy at HVBH (weighted n=5,235) and 4,399 patients underwent nonelective laparoscopic cholecystectomy at LVBH (weighted n=21,995). The results showed LVBH had higher rates of post-operative haemorrhage (p=0.03) and any complication (p=0.05)

Ventral hernia repair

For patients undergoing elective ventral hernia repair, there were 514 patients at HVBH (weighted n=2,570) and 1,130 patients at LVBH (weighted n=5,650). Patients at LVBH had still had higher rates of pulmonary failure (p<0.0001) as well as having an increased risk of having any individual complication (p=0.01). For patients undergoing nonelective ventral hernia repair, there were 314 patients at HVBH (weighted n=1,570) and 1,143 patients at LVBH (weighted n=5,715). Patients at LVBH had higher rates of postoperative death (p=0.03).


The patients that underwent appendectomy (nonelective cases only) included 205 patients at HVBH (weighted n=1,025) and 870 patients at LVBH (weighted n=4,350). There were no statistically significant differences in any preoperative comorbidity, although LVBH had higher rates of postoperative pulmonary failure (3.22% vs. 0.49%, p=0.03) which persisted after propensity weighing (p=0.02).

The authors noted that the pulmonary failure was the most consistently increased complication with higher rates in patients undergoing elective laparoscopic cholecystectomy, elective ventral hernia repair and appendectomy. In addition, they reported that there was a significantly higher rate of mortality at LVBH after elective laparoscopic cholecystectomy and nonelective ventral hernia repair.

Importantly, the authors cautioned that they were unable to identify whether the surgeons performing the general surgery cases were also performing bariatric surgery, adding that the study highlights the overall increased complication rate for morbidly obese patients undergoing general surgery procedures.

“As our results suggest, a bariatric volume to general surgery outcome relationship, it may be that the multimodality pathways required for accreditation at high volume bariatric centres create a culture of improved safety and outcomes for many general surgery procedures performed in morbidly obese patients,” the authors write.

Further information

To access this paper, please click here


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