The risk of complications and mortality in bariatric surgery is associated with certain factors that are common to other patients and procedures, including age above 65 years, the presence of associated diseases (cardiovascular and pulmonary disease, chronic renal failure, liver cirrhosis, etc.), prior abdominal surgery, and the experience of the surgeon and the institution, especially concerning the ability to make an early diagnosis and address complications. The surgical complications observed in the early postoperative period following surgeries performed to treat severe obesity are similar to those associated with other major surgeries of the gastrointestinal tract. However, given the more frequent occurrence of medical comorbidities (such as diabetes, arterial hypertension, and sleep apnea), as well as the difficulty in making an early diagnosis of the complications (due to limitations of the clinical abdominal workup and imaging methods, such as ultrasonography and computed tomography, particularly in highly obese patients with body mass indices >50 kg/m²), these patients require special attention in the early post operative follow-up. Pulmonary thromboembolism, a complication associated with bariatric surgery, also requires greater attention from the medical team given the high mortality rate associated with this condition. Early diagnosis and appropriate treatment of these complications are directly associated with a greater probability of control.