and combining repair techniques with bariatric surgery can improve outcomes and lower the rate of complication for select patients, according to recent guidelines released by the American Society for Metabolic and Bariatric Surgery and the American Hernia Society.
Dr. Emanuele Lo Menzo
Emanuele Lo Menzo, MD, of the Bariatric and Metabolic Institute at Cleveland Clinic Florida in Weston, and his colleagues issued a statement, published in the journal Surgery for Obesity and Related Diseases, based on available evidence from scientific literature on the impact of obesity on hernia surgery and what effect treating obesity has on improving hernia repair outcomes.
The authors noted abdominal wall hernia in obese patients is “a significant and increasingly common challenge for surgeons” and cited recent data from the American College of Surgeons National Surgical Quality Improvement Program that shows 60% of ventral hernia repairs (VHR) are performed on patients with body mass indexes (BMIs) above 30 kg/m2. Overall, they noted that general surgeons perform approximately 350,000 conventional hernia repairs (CHR) and 800,000 incisional hernia (IH) repairs each year.
The literature on the impact of obesity on hernia repair outcomes and the feasibility of a combined operation to address each problem has significant gaps, leaving surgeons to decide on a correct course based on individual patient needs. The guideline offers some recommendations, and notes areas that remain understudied. First, “in patients with severe obesity and [ventral hernia] and both being amenable to laparoscopic repair, combined hernia repair and [metabolic/bariatric surgery] may be safe and associated with good short-term outcomes and low risk of infection.” But the use of synthetic mesh in these patients is not well studied and so the guideline passes on a recommendation of mesh. For those obese patients with symptomatic abdominal wall hernias (AWHs) not amenable to laparoscopy, the guideline notes that metabolic/bariatric surgery first may be the best option.
Risk of hernia in obese patients
Studies suggest there is an increased risk of primary and IH among patients with BMIs greater than 25 kg/m2, with one study finding an 18.2% complication rate after single-incision laparoscopic surgery for patients with BMIs of 40 kg/m2 or higher, compared with a 3.5% complication rate among patients at a normal body weight. Severe BMI also is a risk factor for developing surgical site infection (SSI), which can cause recurrence, the authors said. Evidence from multiple studies further supports BMI as a risk factor for hernia recurrence, and intra-abdominal pressure from obesity increases the risk of developing an AWH.
“While most authors attribute the increased risk for AWH formation in the setting of obesity to BMI alone, others have suggested that abdominal circumference and elevated visceral fat may play a more significant role,” the authors wrote.
However, Dr. Lo Menzo and his colleagues admitted the actual rate of IH is difficult to calculate because some patients may not seek treatment for minimally symptomatic hernias. Patients with higher BMIs may not be aware of or seek treatment for common symptoms of IH such as groin bulge, or when they do seek treatment, it can present with symptoms such as incarceration or strangulation, they said. Patients with higher BMIs also are more likely to be offered “watchful waiting” because of higher complication rates in this patient population, which may contribute to incarceration or strangulation symptoms in these patients, they added.