Faculty Bibliography

In their relative infancy, intragastric balloons (IGB) offer a solution to patients who do not qualify for bariatric surgery due to their body mass index (BMI) or those reticent about major surgery with a promise of 10-15% of total body weight loss (TBWL%). Given a short implantation period of 6 months, weight regain following IGB removal has been commonly noted. This caveat prompted analysis of the addition of weight loss medications for improved efficacy in achieving sustained weight loss results post-IGB removal. In a single-center retrospective analysis from 2015 to 2018, 18 patients (mean age 39.72, 5 males, 13 females) with a saline-filled single intragastric balloon were evaluated for 12 months following IGB insertion. Exactly half of the patients (n=9) were on weight loss medications before, during, or after placement of IGB (IGB-M cohort) to compare to patients with IGBs only (IGB-O cohort). All patients were >18 years old, non-pregnant, and with no previous bariatric surgeries. Data was collected at 0, 3, 6, and 12 month intervals. Mean weight at baseline was 198.33lbs and 223lbs (p=0.814) and mean BMI was 32.79 kg/m2 versus 35.5 kg/m2 (p=0.546), in the IGB-O cohort versus the IGB-M cohort, respectively. At six months, the TBWL% in the IGB-O cohort versus the IGB-M cohort was 12.7% versus 13.1%, while mean BMI was 28.42 versus 31.62 (p=0.645), respectively. Attrition rate was 11.1% by 6 months and 72.2% by 12 months for both cohorts combined. At 12 months, TBWL% in the IGB-O cohort versus IGB-M cohort was 2.8% and 10.7%, while mean BMI was 33.77 and 29.17 (p=0.4), respectively. The most common class of medications utilized were glucagon-like peptide-1 (GLP-1) agonists (37.5%). Phentermine was the single most commonly prescribed medication (25%). The mean number of medications needed for a patient was 1.8. The TBWL% at six months demonstrated a slightly greater 0.4 TBWL% in the IGB-M cohort. This meant weight loss achieved with a balloon or weight loss pharmacotherapy was essentially equivalent in our study at the time of IGB removal at 6 months. However, a stark variance is noted at the 12 month mark in the IGB-O cohort with patients either partially regaining their previously lost weight or losing marginally further with a mean 2.8 TBWL% post IGB removal. Comparatively, the IGB-M cohort patients continued their weight loss or maintained their initial weight loss with a 10.7% TBWL creating a 7.9 TBWL% difference at the 12 month follow up between the two arms. Administration of medications might increase follow-up post IGB removal and decrease attrition rates. Results illustrate a two-pronged approach of combining weight loss medications with IGBs would culminate in a more clinically significant TBWL% with long term sustainability post IGB removal. Larger multi-center studies are recommended in order to achieve significant conclusions. [Formula presented] [Formula presented]
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Purpose: High body mass index (BMI, kg/m²) is a modifiable risk factor that has been associated with the development and progression of osteoarthritis (OA) and knee pain. The gold standard for the treatment of end stage knee OA remains total knee arthroplasty (TKA), though patients with morbid obesity (BMI>=40 kg/m²) are increasingly required to lose weight prior to TKA due to increased surgical risk and a higher rate of complications. Conservative weight-loss approaches often fail to help patients lose the recommended weight prior to TKA, potentially making them ineligible for surgery. Recent studies have shown that patients who undergo bariatric surgery experience short-term improvements in knee functionality and decreased pain, either obviating the need for arthroplasty - or at least improving the success of subsequent total knee replacements. Here we present interim data from the trial entitled "Surgical Weight-loss to Improve Functional Status Trajectories following arthroplasty for painful knee osteoarthritis". This current multi-center, prospective study compares pain and functional outcomes in patients receiving bariatric surgery prior to TKA versus obese patients who go straight to TKA.
Method(s): We recruited patients with BMI >=40 kg/m² and painful knee OA who met the indications for TKA from the bariatrics, orthopedics and rheumatology clinics at the four hospital centers. Patients with a BMI >35 kg/m² were also recruited if they had a qualifying comorbid condition including obstructive sleep apnea, diabetes, hypertension or hyperlipidemia. Patients were assigned to the bariatric (BAR) or TKA (TKA) arms based on surgical choice (goal n=150 for each arm), with all bariatric patients having anatomy-altering sleeve gastrectomy or gastric bypass, and not laparoscopic gastric banding. At baseline and several time points after surgery (see figure), we documented height, weight, the Knee injury and Osteoarthritis Outcome Score (KOOS), visual analog pain (VAS) scales, and the Western Ontario and McMaster Universities Arthritis Index (WOMAC), and had patients perform functional assessments (Timed-Up and Go, 30-second Chair Stand and 40-meter fast paced walk test). We targeted minimum detectable change (MDC) in outcomes for the VAS for knee pain (33% reduction), Timed Up and Go (decrease by 2 seconds), 30-second Chair Stand (increase by 2 reps), 40-meter fast paced walk (increase by 0.16 m/s), WOMAC score (16% reduction), and the KOOS pain score (10-point improvement). Using a logistic regression to adjust for age and baseline BMI, we compared the percentage of patients in the two arms who achieve an MDC for the various outcomes.
Result(s): For the current analysis, 20 bariatric surgery patients and 22 TKA patients completed their 6-month follow-up visits. Each subcohort had a similar sex distribution (15% vs 14%, p=0.999) but the bariatric group was younger (53 vs 61 years old, p=0.0045) and had a higher baseline BMI (47.1 vs 40.9, p=0.0009). Many bariatric patients achieved significant improvement in knee pain and function as evidenced by the MDC in the various tests, though the percent with MDC consistently tended to be higher in the TKA cohort. These MDC benchmarks included the 30-second Chair Stand (TKA 60% vs BAR 29%, p=0.085), KOOS pain score (TKA 89% vs BAR 65%, p=0.130), the Visual Analog Pain Scale (TKA 50% vs BAR 34%, p=0.390), Timed Up and Go (TKA 45% vs BAR 21%, p=0.205), the 40-meter fast paced walk (TKA 61% vs BAR 42%, p=0.319), and the WOMAC (TKA 81% vs BAR 59%, p=0.225). Many of the bariatric patients have had subsequent arthroplasty, but not enough time has passed to report levels of improvement.
Conclusion(s): In morbidly obese patients who are eligible for TKA, bariatric surgery may result in modest improvements in knee pain and function when compared to TKA at 6 months post operatively. In addition to potentially altering the need for and timing of TKA, surgical weight loss may result in improved TKA outcomes. This study was supported by the Investigator Initiated Study Program of Ethicon-Endo Surgery, Inc. (Grant Number: 14-621). [Formula presented]
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INTRODUCTION: Bariatric surgery has become a common therapeutic approach to obesity. However, bariatric procedures may affect bowel habits due to changes in dietary intake as well as altered anatomy. To date, few studies have evaluated the impact of bariatric surgery on post-operative constipation. The aim of this study is to determine if patients experience a greater rate of constipation after bariatric surgery compared to non-bariatric controls.
METHOD(S): A retrospective chart review at New York Langone Hospital (NYU) was performed on 160 bariatric surgery patients who had surgery in the year 2012 and 160 control patients with BMI < 30 kg/m2 seen in primary care in 2012. Reports of constipation were recorded up until November 2018. Exclusion criteria included those with inflammatory bowel disease or hereditary colorectal cancer syndromes prior to age 50. The primary outcome was diagnosis of post-operative constipation. Secondary outcomes included rates of constipation according to surgical procedure. Presence of constipation was recorded if listed on the problem list or if medications for constipation were prescribed. Logistic regression and chi-squared testing was used to assess differences in groups.
RESULT(S): Table 1 shows patient characteristics of the study population. The average age of bariatric surgery patients was 64.1 years compared to 69.8 in the control group. Overall, 20% of bariatric patients were diagnosed with constipation compared to 15% of controls (P = 0.239). Constipation rates post-bariatric surgery were 17.9% in lap band, 20.6% in sleeve gastrectomy, and 7.1% in gastric bypass patients (P = 0.256). A logistic regression controlling for age, sex, and Charlson co-morbidity index was performed between controls and post-surgery subjects. This revealed no significant difference in rates of constipation between the two groups (OR 1.158, 95% CI 0.790 - 1.696 P-value = 0.45). There was, however, a significant difference in constipation rates between the bariatric group pre-surgery (13.8%) and post-surgery (17.5%) (P = < 0.001) (Table 2).
CONCLUSION(S): Bariatric surgery patients experience significantly higher rates of constipation after surgery compared to prior to surgery, but similar rates to controls without obesity. Constipation impairs quality of life and is associated with significant health care costs. Further studies investigating the mechanisms underlying this increase in constipation after bariatric surgery and effective measures to treat it are warranted. (Figure Presented)

Background/Purpose : Weight loss in obese patients can reduce knee osteoarthritis (OA) pain, even when physical therapy and intra-articular injections have failed. The impacts of either non-surgical or surgical weight loss on knee OA pain have been reported separately, but few studies have assessed them conjointly. While the decrease in mechanical load helps, the contribution of metabolic changes is less clear. We aimed to compare biomarker changes with weight loss as predictors of knee pain improvement, and consider a threshold of total weight loss necessary for these changes. Methods : Patients from the NYU Langone Weight Management program were screened for knee pain prior to bariatric surgery or the start of a medical weight loss (MWL) regimen. We excluded patients with autoimmune disease, recent malignancy, recent intra-articular knee injections, and lack of OA by Kellgren-Lawrence (KL) x-ray grading. The BMI, Knee Injury and Osteoarthritis Outcome Score (KOOS) for pain, and blood samples were obtained at baseline and 1, 3, 6 and 12 months for evaluation of pain and biomarker levels. Results : Of 140 patients screened, 81 were eligible and enrolled (82.7% female; BMI 45.2+/-9.6 kg/m2, 31-74; age 52+/-12 years, 30-80). A total of 49 patients had surgery (10 bypass, 30 sleeve, 9 LapBand) and 24 medical weight loss. 33 patients completed visits up to 6 months (2 bypass, 18 sleeve, 6 LapBand, 7 MWL). By 1 month, the surgical patients had lost much more total weight than the MWL group (9.8% vs 4.1 %, p=0.001), and realized marked pain relief (p< 0.001). By 6 months both groups had continued to lose weight, proportionately greater for surgical patients with further pain improvement. (Figure 1) Leptin levels dropped at 1 and then 6 months with both methods of weight loss. The pro-inflammatory protein IL-1Ra decreased significantly by 6 months in the bariatric patients, but increased with the medical regimen across both time points. Soluble vascular adhesion protein 1 (sVAP-1), another pro-inflammatory protein that facilitates leukocyte infiltration, decreased at both the 1 and 6 month intervals -but much more in MWL than in surgical patients. Consistent with the literature, the anti-inflammatory soluble receptor for advanced glycation endproducts (sRAGE) mirrored KOOS pain improvement only in surgical patients and stabilized after 1 month, but did not change in the MWL group. (Table 1) In a subgroup analysis, the 14 surgical patients who lost at least 10% of Figure 1. Surgical and medical outcomes for % total weight loss (TWL), knee pain and biomarkers Table 1. total weight by 1 month had significantly less pain at 6 months than the 12 who did not meet the threshold (DELTAKOOS 47.5 vs 29.9) but the biomarker levels were similar. (Figure 2) Conclusion : Surgical and medically supervised weight loss both lead to significant decreases in adiposity, but only those having bariatric surgery realize significant pain relief. The anatomical changes of surgical (vs. medical) weight loss result in different metabolic cascades given divergent biomarker trends. Bariatric patients who lose more than 10 percent of total body weight within the first month are more likely to have better pain relief by 6 months, but the biomarker changes reflect anatomic intervention -and are not dependent on the degree of surgical weight loss

Introduction: The gastrojejunostomy (GJ) during Roux-en-Y gastric bypass (RYGB) can be performed by stapled or hand-sewn techniques, and is at risk for anastomotic stricture, reported in the literature at rates from 0 to 33%. This study reviews a single center's experience with anastomotic stricture and intervention required. Methods and Procedures: A retrospective chart review was performed of 904 patients who underwent RYGB as primary or revisional surgery at a single institution from October 2000 through September 2017. There were 182 patients excluded for follow up duration of less than 1 year, 5 for an esophagojejunostomy rather than GJ, and 1 for gastroparesis as the surgical indication rather than morbid obesity. This left 716 patients to be included in the study. Demographic and operative data were collected including technique for GJ, postoperative follow up, and complications, with a focus on GJ stricture and subsequent interventions.
Result(s): Gastrojejunostomy (GJ) was performed with a 25 CEEA stapler in 674 (94.1%) patients, with a linear stapler in 25 (3.5%), was hand-sewn in 7 (1.3%), and the technique was unknown in the remaining 8 (1.1%). Roux-en-Y gastric bypass was performed as a primary surgery in 522 (72.9%) patients and as a revisional surgery in 194 (27.1%). Stricture of the GJ was diagnosed in 29 (4.1%) patients. The average time to diagnosis of early strictures occurring prior to 3 months was 40.3 days, and for late strictures was 871 days. By technique, stricture was diagnosed in 26 (3.9%) patients in the 25CEEAgroup, 1 (4%) in the linear stapler group, and 2 (22.2%) in the hand-sewn anastomosis group. In primaryRYGBpatients stricture was diagnosed in 20 (3.8%) patients, and in revisionalRYGB in 9 (4.6%) patients (p = 0.626). Esophagogastroduodenoscopy (EGD) with dilation was performed at least once (1-9 times) in 26 patients, 2 with concomitant stenting, 2 required operative intervention, and 1 patient awaits operative intervention. Both patients who required surgery also had marginal ulcers, and possible gastro-gastric fistula at time of surgery.
Conclusion(s): The results of this study show that the 25 CEEA circular stapler is a reasonable technique for performance of the GJ anastomosis in RYGB, with a stricture rate of 3.9%. There is also a slightly increased stricture rate in revisional surgical patients, though not statistically significant

BACKGROUND:When administered as a continuous infusion, ketamine is known to be a potent analgesic and general anaesthetic. Recent studies suggest that a single low-dose administration of ketamine can provide a long-lasting effect on mood, but its effects when given in the postoperative period have not been studied. OBJECTIVE:We hypothesised that a single low-dose administration of ketamine after bariatric surgery can improve pain and mood scores in the immediate postoperative period. DESIGN/METHODS:We performed a randomised, double-blind, placebo-controlled study to compare a single subanaesthetic dose of ketamine (0.4 mg kg) with a normal saline placebo in the postanaesthesia care unit after laparoscopic gastric bypass and gastrectomy. SETTING/METHODS:Single-centre, tertiary care hospital, October 2014 to January 2018. PATIENTS/METHODS:A total of 100 patients were randomised into the ketamine and saline groups. INTERVENTION/METHODS:Patients in the ketamine group received a single dose of ketamine infusion (0.4 mg kg) in the postanaesthesia care unit. Patients in the placebo groups received 0.9% saline. OUTCOME MEASURES/METHODS:The primary outcome was the visual analogue pain score. A secondary outcome was performance on the short-form McGill's Pain Questionnaire (SF-MPQ). RESULTS:There were no significant differences in visual analogue pain scores between groups (group-by-time interaction P = 0.966; marginal group effect P = 0.137). However, scores on the affective scale of SF-MPQ (secondary outcome) significantly decreased in the ketamine group as early as postoperative day (POD) 2 [mean difference = -2.2 (95% bootstrap CI -2.9 to 1.6), Bonferroni adjusted P < 0.001], compared with placebo group in which the scores decreased only by POD 7. Scores on the total scale of SF-MPQ for the ketamine group were smaller compared with the placebo group (P = 0.034). CONCLUSION/CONCLUSIONS:Although there was no significant difference between ketamine and placebo for the primary outcome measure, patients who received ketamine experienced statistically and clinically significant improvement in their comprehensive evaluation of pain, particularly the affective component of pain, on POD 2. However, future studies are needed to confirm the enduring effects of ketamine on the affective response to postoperative pain. CLINICAL TRIAL REGISTRATION/BACKGROUND:NCT02452060.

INTRODUCTION/BACKGROUND:Bariatric surgery reduces obesity and knee osteoarthritis (OA) pain, but some patients improve more than others. We aimed to identify characteristics that predict this knee pain improvement. METHODS:We reviewed NYU Langone Health bariatrics records (2002-2015) and called eligible patients reporting pre-operative knee pain. Patients were asked to rate their pain on a 10-point scale at three time points: before surgery, one year post-surgery, and time of survey administration. Subjects were asked about pre-operative knee injuries and surgeries, presence of OA in other joints, and OA family history. Data were analyzed using paired t-tests and ANOVA. RESULTS:Of 125 eligible patients reporting knee pain, we analyzed the 120 patients who had laparoscopic gastric band (LAGB) surgery. The cohort was 78.3% female, with an average age at surgery of 49.7 ± 10.2 years. There was no correlation between pre-operative body mass index (BMI) and knee pain reduction at one year post-LAGB, but the subgroup with the most BMI improvement reported the most knee improvement (p = 0.043). We found significantly better pain reduction after one year in younger patients (p = 0.009). Those with prior knee injuries improved less than those who were injury-free (p = 0.044), but a history of prior knee surgery was not similarly significant. Patients with multifocal OA improved less (p = 0.001). CONCLUSION/CONCLUSIONS:Younger knee OA patients and those without prior knee injury or other OA involvement, experience more knee pain relief from LAGB weight loss surgery. LAGB may be a viable treatment option for knee OA pain, irrespective of the degree of obesity.