Postoperative Care

Key concepts for recovery after gastrointestinal surgery are employed, including early ambulation, use of incentive spirometry, and monitoring voids. Early initiation of diet with advancement as tolerated has been shown to be safe and effective in prompt recovery after gastrointestinal surgery [16]. Specifically, post-bariatric surgery, this takes the form of initiation of bariatric clear liquids with advancement to bariatric full liquids by postoperative day 1 and has been shown to decrease length of stay without increasing morbidity [17]. Antiemetic use is important in the bariatric surgical population, as postoperative nausea and vomiting (PONV) are seen not infrequently. Aggressive regimens to combat PONV have been shown to be effective in reducing symptoms and decreasing length of stay [18, 19]. Such regimens may include perioperative administration of ondansetron, dexamethasone, and/or prophylactic placement of transdermal scopolamine patch.

Opioid reduction helps with decreasing PONV , and therefore a multimodal approach to postoperative analgesia is most effective. Local anesthetics employed at the time of surgery, sometimes in the form of transversus abdominis plane blocks, combined with nonsteroidal anti-inflammatory medications, acetaminophen, and opioids, appear to be an effective strategy. The American Society for Metabolic and Bariatric Surgery (ASMBS) has developed perioperative pathways as a resource for evidence-based perioperative management of the bariatric patient, and have published a pathway for sleeve gastrectomy [20].

Routine use of postoperative radiological upper gastrointestinal series (UGIS) to assess for leak has fallen out of favor, especially following sleeve gastrectomy. The vast majority of these tests are negative, and patients who subsequently develop leaks in the first 2–3 weeks following surgery may have had a normal UGI [21]. Vital sign derangements and clinical factors, such as fever, tachycardia, leukocytosis, or elevated pain scores, may serve as screening tools to guide selective use of UGIS to investigate for leak. In addition, UGI may be ordered to evaluate for obstruction or twisting of the sleeve in patients with persistent emesis or dysphagia.

Outcomes

Weight loss is a primary outcome measure following bariatric surgery. There have been several long-term studies (>5 years follow-up data) and meta-analyses specifically focused on the effectiveness of sleeve gastrectomy for weight loss. Percent excess weight loss (EWL) and total weight loss (TWL) are common parameters reported in the literature, and long-term studies show weight loss following sleeve gastrectomy in the range of 53–76% EWL and 24–26% TWL [22–26]. Preoperative BMI has been shown to be a predictor of weight loss success following bariatric surgery, with lower preoperative BMI associated with greater percentage of weight loss [27]. Other factors, such as age and presence of hypertension or diabetes, also seem to accurately predict postoperative weight loss [28]. Weight regain or inadequate weight loss remain challenges, estimated to occur in approximately 28% of sleeve gastrectomy cases long term with a range of 14–37%, but rates are highly inconsistent in the bariatric surgical literature due to nonuniform definitions and methods of reporting [29, 30].

Improvement or remission of obesity-related comorbidities remains an important aspect of metabolic/bariatric surgery. Rates of diabetes remission have been reported to be around 70% overall, regardless of preoperative BMI, and varies among procedure type (89% with biliopancreatic diversion, 77% after RYGB, and 60% following SG) [31]. Five-year data from a randomized trial revealed bariatric surgery with intensive medical therapy was more efficacious in treating hyperglycemia than medical therapy alone [32]. There are now several scoring systems available that surgeons may use to help predict the probability of diabetes remission following bariatric surgery [33, 34]. Nondiabetic comorbid conditions also seem to improve in the post-bariatric surgery patient. Obstructive sleep apnea (OSA) is quite common in patients with morbid obesity, and sleeve gastrectomy has been objectively shown to significantly improve OSA using the modified Epworth Sleepiness Scale questionnaire (92% improvement) and apnea–hypopnea index (81% improvement) [35]. Nonalcoholic fatty liver disease (NAFLD) is increasing in prevalence, and bariatric surgery, including sleeve gastrectomy specifically, has been shown to induce histological improvement in liver fibrosis, therefore gaining significant traction as an indication for bariatric surgery [36–39]. Nontraditional conditions such as pulmonary hypertension and interstitial lung disease no longer appear to be contraindications and actually have been demonstrated to improve following bariatric surgery, which may positively affect candidacy for lung transplantation [40, 41].

Overall rates of morbidity are low, with a 2–3% rate of 30-day major adverse events following sleeve gastrectomy [42]. Early complications were found to occur at a lower rate among those undergoing SG as compared to RYGB [43]. Thirty-day readmission was noted to be lower among SG patients as well (3.8 vs. 6.1% for RYGB), with the most common reasons being nausea, vomiting, and dehydration [44]. A recent meta-analysis reviewed randomized controlled trials for rates of late postoperative complications and found a lower rate of major and minor complications for SG versus RYGB, as well as a greater reduction in need for additional interventions, although none of these reached statistical significance [45]. Sleeve gastrectomy may be performed safely as a reoperative procedure for failed adjustable gastric banding and has a better risk profile when performed as a single-stage conversion as compared to band to RYGB [46].

Using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database , reported rates of 30-day mortality was 0.1% for SG and 0.2% for RYGB, as well as lower unplanned intensive care unit admissions or reoperation for those undergoing sleeve gastrectomy [47]. Moreover, in a large, population-based study, obese patients who had not undergone bariatric surgery had a higher risk of all-cause mortality compared to patients who had bariatric surgery, with an adjusted hazard ratio of 2.02 over a median follow-up of 4.5 years [48].

Management of Complications

While bariatric surgery has a very favorable risk profile, there are particular perioperative events that may cause significant patient morbidity or, in rare circumstances, mortality. Bleeding can occur following sleeve gastrectomy, most commonly from the longitudinal staple line, although other sources of bleeding can include the cut edge of the mesentery, splenic hilar vessels, diaphragmatic vessels, or parenchymal injuries to the spleen or pancreas. Rates of postoperative bleeding are estimated to be around 0.5–2%, a minority of which may require reoperation [49]. Technique appears to play a partial role in prevention of staple line leaks, with multiple studies demonstrating a reduction in postoperative hemorrhage with the use of staple line reinforcement [50, 51].

Gastric leak following sleeve gastrectomy remains one of the most feared complications. Due to the configuration of the longitudinal gastrectomy, the intraluminal pressure of the sleeve increases relative to a normal stomach, and the most proximal extent of the staple line appears to be most vulnerable to leak. Oftentimes, a distal stricture or twisting related to improper technique, ischemia, or other factors may be found in association with sleeve leaks. Overall leak rate has been reported to be in the range of 0.3–3%, and operative technique may play a role, as some studies found oversewing of the staple line resulted in fewer leaks, while others showed staple line reinforcement to improve outcomes [52, 53]. The primary goal of treatment remains control of intra-abdominal sepsis, which may be achieved with percutaneous drainage or early surgical exploration, as well as parenteral antibiotics and enteral nutrition. In certain circumstances, depending on the acuity, character, and location of the leak, advanced endoscopic interventions such as internal drainage, stenting, clipping, or sewing may be options. For chronic, nonhealing leaks, conversion to a Roux-en-Y configuration may be considered. During workup of a sleeve leak, if a distal obstruction is encountered, it is paramount to address and treat this in order to facilitate healing of the leak. Options include endoscopic dilation or stenting depending on the nature of the obstruction or conversion to Roux-en-Y gastric bypass.

Those undergoing bariatric surgery are at increased risk for venous thromboembolic (VTE) events due to risk factors such as diabetes mellitus, hypertension, and venous stasis, in addition to obesity, although they occur infrequently with a reported incidence of 0.2–3.5% range [54, 55]. Risk also varies with procedure type, with sleeve gastrectomy carrying a higher risk than gastric bypass [56]. Pulmonary embolism (PE) is the leading cause of mortality following bariatric surgery and therefore remains a significant focus on quality improvement and patient safety initiatives [57]. In addition, the vast majority of VTE events occur post-discharge from inpatient hospitalization, usually within 30 days of surgery [58]. A unique but now well-recognized VTE event is porto-mesenteric vein thrombosis (PVT) . There is a paucity of literature on this adverse event, but the overall incidence is estimated to be less than 0.5% among all bariatric procedures, with the highest rate following sleeve gastrectomy [59]. The mainstay of therapy is systemic, therapeutic anticoagulation.

Evidence-based protocols are becoming widespread among bariatric surgery programs to help mitigate the risk of VTE . Aggressive prophylaxis is an integral part of these pathways and generally includes lower extremity compression with sequential compression devices (SCDs), early ambulation, and pharmacologic prophylaxis. Unfractionated (UH) and low-molecular-weight heparins (LMWH) are commonly used, though LMWH is generally preferred due to low-level evidence that suggests a greater reduction in VTE rates without increased risk of bleeding compared with UH [60]. There are now several validated risk calculators readily available as smartphone apps that help to predict the individualized risk of VTE and also assist in making recommendations for post-discharge chemoprophylaxis for those at highest risk.

Gastroesophageal reflux disease following sleeve gastrectomy remains an area of intense investigation. Many surgeons propose significant preoperative reflux as a relative contraindication to sleeve gastrectomy due to concern regarding exacerbation of GERD following the procedure. Others maintain that reflux symptoms may improve with weight loss following sleeve gastrectomy and therefore should not be considered a contraindication. The incidence and significance of post-sleeve GERD (including esophagitis and Barrett’s esophagus), as well as the approach to evaluation and management, remain controversial at present time. Reflux symptoms following sleeve gastrectomy have been studied sparingly, but a retrospective review from a single center using the validated GERD Health-Related Quality of Life (GERD-HRQL) survey demonstrated new-onset heartburn to be present among 47% of their cohort, as well as increased rates of dysphagia and regurgitation [61]. This study also concluded that, in their analysis, none of the preoperative variables were able to predict de novo or worsening of reflux in the postoperative period. Other studies have demonstrated the opposite effect, with improvements in reflux symptoms following sleeve gastrectomy [62].

Physiologic changes following sleeve gastrectomy have been demonstrated based on objective analysis with pH studies and high-resolution manometry, reporting an increase in esophageal acid exposure and decrease in lower esophageal sphincter (LES) pressure [63]. Another study correlated the LES distensibility with post-sleeve gastrectomy GERD symptoms and found that, while the LES was weakened post-procedure, there was no predictable correlation to the change in reflux symptoms, arguing that post-sleeve GERD has a multifactorial etiology [64]. To determine rates of esophagitis and Barrett’s esophagus following sleeve gastrectomy, one group performed routine endoscopic surveillance at 1 month and 1 year, followed by annually on a selective basis [65]. Those experiencing reflux symptoms were placed on proton pump inhibitor therapy during their follow-up surveillance (100% follow-up at 1 year, declining over time to 29% at 5+ years). They reported a 15.5% rate of esophagitis and 1.2% rate of Barrett’s esophagus based on histological examination.

Prevention of post-sleeve reflux by surgical technique has been described, with specific data suggesting routine circumferential hiatal dissection during sleeve gastrectomy may in fact be a risk factor for the development of post-sleeve GERD [66]. Most would agree that initial treatment for post-sleeve reflux would be initiation of proton pump inhibitor (PPI) therapy, and previous literature suggests that patients generally have a favorable response to this in the majority of cases [67]. For those patients that do not respond to PPI therapy or prefer alternative options, several interventions exist. The traditional approach has been to convert refractory reflux after sleeve gastrectomy to Roux-en-Y gastric bypass, which still serves as a viable and often-used option with great success. Other interventions that are in variable stages of experience and acceptance include endoscopy radiofrequency ablation to the LES or laparoscopic placement of a magnetic sphincter augmentation device , which seems to have promising early results [68].