EFFECT OF OBESITY AND ROUX-EN-Y GASTRIC SURGERY ON OMEPRAZOLE PHARMACOKINETICS

Background: The prevalence of obesity is increasing globally. Objectives: To evaluate whether gastric bypass surgery modifies the bioavailability and pharmacokinetic (PK) parameters of Omeprazole. Setting: Hospital Clínico San Carlos, Madrid, Spain. Methods: Controlled, open-label, bioavailability clinical trial in patients undergoing Roux-en-Y gastric bypass (RYGB). Healthy patients with obesity (BMI>35) were included and assessed for Omeprazole PK before RYGB and after (1 and 6 months). PK sampling was done at baseline and several times up to 12 h after drug dosing. Pre- and post-surgery parameters were compared using paired ANOVA or Wilcoxon tests, and Control vs. Cases using ANOVA or Mann Whitney tests. Given the post-surgery change in body weight, parameters were corrected by dose/body-weight. Results: Fourteen Case and 24 Control subjects were recruited, 92% were women (N= 35/38). In patients who underwent RYGB, Cmax was significantly reduced at 1 and 6 months after surgery compared with pre-surgery values (p=0.001). Regarding the AUC, the values are lower at 1 and 6 months after surgery than at baseline (p<0.001).The drug clearance was also increased in the first month after surgery. No differences were found between patients 6 months after surgery and Controls. Cmax and AUC corrected by dose/body-weight were significantly different between the baseline surgery subjects and Controls. Conclusions: Omeprazole bioavailability is reduced in patients with obesity at 1 and 6 months after RYGB. However, Omeprazole PK parameters 6 months after RYGB are similar to control subjects, and thus no dose correction is required after RYGB for a given indication.

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Blood pressure reduction after gastric bypass surgery is explained by a decrease in cardiac output

Journal of Applied Physiology ◽

10.1152/japplphysiol.00362.2016 ◽

2017 ◽

Vol 122 (2) ◽

pp. 223-229 ◽

Cited By ~ 4

Author(s):

Peter M. van Brussel ◽

Bas van den Bogaard ◽

Barbara A. de Weijer ◽

Jasper Truijen ◽

C.T. Paul Krediet ◽

...

Keyword(s):

Blood Pressure ◽

Gastric Bypass ◽

Body Weight ◽

Cardiac Output ◽

Baroreflex Sensitivity ◽

Bypass Surgery ◽

Gastric Bypass Surgery ◽

Left Ventricular ◽

Ventricular Contractility ◽

Left Ventricular Contractility

Blood pressure (BP) decreases in the first weeks after Roux-and-Y gastric bypass surgery. Yet the pathophysiology of the BP-lowering effects observed after gastric bypass surgery is incompletely understood. We evaluated BP, systemic hemodynamics, and baroreflex sensitivity in 15 obese women[mean age 42 ± 7 standard deviation (SD) yr, body mass index 45 ± 6 kg/m2] 2 wk before and 6 wk following Roux-and-Y gastric bypass surgery. Six weeks after gastric bypass surgery, mean body weight decreased by 13 ± 5 kg (10%, P < 0.001). Office BP decreased from 137 ± 10/86 ± 6 to 128 ± 12/81 ± 9 mmHg ( P < 0.001, P < 0.01), while daytime ambulatory BP decreased from 128 ± 14/80 ± 9 to 114 ± 10/73 ± 6 mmHg ( P = 0.01, P = 0.05), whereas nighttime BP decreased from 111 ± 13/66 ± 7 to 102 ± 9/62 ± 7 mmHg ( P = 0.04, P < 0.01). The decrease in BP was associated with a 1.6 ± 1.2 l/min (20%, P < 0.01) decrease in cardiac output (CO), while systemic vascular resistance increased (153 ± 189 dyn·s·cm−5, 15%, P < 0.01). The maximal ascending slope in systolic blood pressure decreased (192 mmHg/s, 19%, P = 0.01), suggesting a reduction in left ventricular contractility. Baroreflex sensitivity increased from 9.0 [6.4–14.3] to 13.8 [8.5–19.0] ms/mmHg (median [interquartile range]; P < 0.01) and was inversely correlated with the reductions in heart rate ( R = −0.64, P = 0.02) and CO ( R = −0.61, P = 0.03). In contrast, changes in body weight were not correlated with changes in either BP or CO. The BP reduction following Roux-and-Y gastric bypass surgery is correlated with a decrease in CO independent of changes in body weight. The contribution of heart rate to the reduction in CO together with enhanced baroreflex sensitivity suggests a shift toward increased parasympathetic cardiovascular control. NEW & NOTEWORTHY The reason for the decrease in blood pressure (BP) in the first weeks after gastric bypass surgery remains to be elucidated. We show that the reduction in BP following surgery is caused by a decrease in cardiac output. In addition, the maximal ascending slope in systolic blood pressure decreased suggesting a reduction in left ventricular contractility and cardiac workload. These findings help to understand the physiological changes following gastric bypass surgery and are relevant in light of the increased risk of heart failure in these patients.

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Determinants of Adequate Response of Patient Undergoing Roux-en-y Gastric Bypass Surgery

10.21203/rs.3.rs-59391/v1 ◽

2020 ◽

Author(s):

Thales Philipe Rodrigues Silva ◽

Flávia Moraes Silva ◽

Larissa Loures Mendes ◽

Alexandra Dias Moreira D'assunção ◽

Lauro Pinheiro Ferreira de Araujo ◽

...

Keyword(s):

Weight Loss ◽

Gastric Bypass ◽

Logistic Regression ◽

Bypass Surgery ◽

Gastric Bypass Surgery ◽

Inadequate Response ◽

Post Surgery ◽

Adequate Response ◽

Follow Up Care

Abstract INTRODUCTION: Roux-en-Y gastric bypass surgery (RYGB) is known to induce, on average,60 to 75% excess body weight loss between 18 and 24 months post-surgery. However, several studies have shown weight regain after two years post-surgery, thus patients must have adequate follow-up in order to guarantee and/or maintain response to RYGB. AIM: To evaluate the determinants of adequate response in patients who underwent RYGB. METHODS: A longitudinal study with 193 adults who underwent RYGB between 2012 and 2014. Adequate response to RYGB was determined by Excess Weight Loss (%EWL). Logistic regression models were constructed to verify the degree of association between adequate response of patient after RYGB and determinants of variable risk based on estimate Odds Ratios (OR). RESULTS: RYGB improves Systemic arterial hypertension (SAH), Diabetes Mellitus (DM) and body mass index (BMI). From the multivariate logistic regression model, being female and not having SAH and DM reduce the chance of inadequate RYGB response. Regarding preoperative BMI, an increase in one unit of kg/m2 was associated with increased odds of inadequate response after RYGB. And patients who did not receive follow-up care with a psychologist or psychiatrist in the postoperative period presented higher odds of inadequate response to RYGB. CONCLUSION: The findings of this study contribute to the effective planning of interventions by multi-professional teams involved in RYGB, aimed at offering a better follow-up care focused mainly on post-surgery changes and adequate RYGB response.

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Gastric Bypass Surgery Causes Body Weight Loss Without Reducing Food Intake in Rats

Obesity Surgery ◽

10.1007/s11695-007-9392-8 ◽

2008 ◽

Vol 18 (4) ◽

pp. 415-422 ◽

Cited By ~ 25

Author(s):

Marianne W. Furnes ◽

Karin Tømmerås ◽

Carl-Jørgen Arum ◽

Chun-Mei Zhao ◽

Duan Chen

Keyword(s):

Weight Loss ◽

Gastric Bypass ◽

Body Weight ◽

Food Intake ◽

Bypass Surgery ◽

Gastric Bypass Surgery ◽

Body Weight Loss

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Respiratory failure of two sp gastric bypass patients and subsequent rescue with extracorporeal membrane oxygenation

Perfusion ◽

10.1191/0267659106pf837oa ◽

2006 ◽

Vol 21 (1) ◽

pp. 73-76 ◽

Cited By ~ 7

Author(s):

L B Mongero ◽

J R Beck ◽

K A Charette ◽

A Stewart

Keyword(s):

Gastric Bypass ◽

Respiratory Failure ◽

Extracorporeal Membrane Oxygenation ◽

Weight Loss Surgery ◽

Gastric Bypass Surgery ◽

Femoral Vein ◽

Gastrointestinal Surgery ◽

Membrane Oxygenation ◽

Post Surgery ◽

The Right

Severe obesity is a chronic condition that is difficult to treat through diet and exercise alone. Gastrointestinal surgery for obesity (bariatric surgery) alters the digestive process by either restrictive surgical alterations or malabsorptive operations. Some 10 - 20% of patients who have weight-loss surgery require follow-up operations to correct complications. Hypoxemia after gastric bypass surgery for morbid obesity, a reported complication, can occur as early as 24 h post surgery. Two patients presented with severe hypoxia and were placed on veno-venous extracorporeal membrane oxygenation (ECMO). Patient No. 1 had an obstruction of the alimentary limb of the gastric bypass due to suture adhesions, and patient No. 2 had an incarcerated diaphragmatic hernia. While on ECMO, ventilation using a protective strategy (60% FiO2, pressure-controlled ventilation inspiratory pressure (PCV) IP 25-27, positive end-expiratory pressure (PEEP) 10-14, permissive hyper-capnia) was employed. An inflow cannula to the level of the right atrium served as arterial outflow from the circuit to the patient, while the femoral vein served as venous inflow to the ECMO circuit. Although ECMO in adult respiratory failure is often used as the last resort due to serious associated adverse events, we report two patients with life-threatening complications from gastric bypass who were rescued, resuscitated to day 7, and uneventfully discharged from the hospital to home.

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Changes in Resting Energy Expenditure following Gastric Bypass Surgery: Impact on Total Body Weight.

Proceedings of The Nutrition Society ◽

10.1017/s0029665120004450 ◽

2020 ◽

Vol 79 (OCE2) ◽

Author(s):

Fathimath Naseer ◽

Ruth Price ◽

Adele McElroy ◽

Carel Le Roux ◽

Tamsyn Redpath ◽

...

Keyword(s):

Weight Loss ◽

Gastric Bypass ◽

Body Weight ◽

Energy Expenditure ◽

Resting Energy Expenditure ◽

Total Body Weight ◽

Post Surgery ◽

Significant Difference ◽

Total Body ◽

Ree Group

AbstractBariatric surgery, including Gastric Bypass (GBP) Surgery, is the most efficient modality to manage severe obesity. Resting Energy Expenditure (REE) is an area of interest in the context of weight loss (WL) as it has been postulated to be an independent predictor of WL success following GBP. As such, the aim of this study is to investigate the impact of REE on WL following GBP. 31 GBP patients (77.4% females BMI 45.5 ± 7.0kg/m2 ; 47.3 ± 11.6y) and 32 weight-stable controls (46.9% females; BMI 27.0 ± 4.6kg/m2 ; 41.1 ± 13.5y) were assessed at one-month pre-surgery and at 3 and 12-months post-surgery. Fat mass (FM) and fat-free mass (FFM) were measured using dual energy X-ray absorptiometry (Lunar iDXA, GE Healthcare). REE was measured under standardised conditions using indirect calorimetry (ECAL, Metabolic Health Solutions). Statistical analyses were performed with SPSS v24.0, Armonk, NY. Multiple regression analysis showed that FM (P = 0.001), FFM (P < 0.0001) and gender (P = 0.012) significantly predicted the interindividual variability in REE. Total body weight (TBW) was removed from the model due to collinearity. Adjusted-REE values were then generated using the above predictor variables. Low-REE and high-REE groups were created using within-group adjusted-REE split. At both follow-ups (3- and 12-months post-surgery), patients had a greater reduction in TBW, FM, FFM, measured-REE and adjusted-REE values compared with controls (P < 0.0001). There was also no significant difference between measured and adjusted-REE values at all time-points (P > 0.05). Patients with high REEs at baseline lost more TBW than those in the low-REE group at 3-months post-surgery (-24.9 ± 6.5 kg vs. -16.6 ± 7.0 kg; P = 0.005) and 12-months post-surgery (-41.3 ± 12.5 kg vs. -25.8 ± 10.4.0 kg; P = 0.003). There was no significant difference in mean TBW changes for controls in the low-and high-REE groups at both follow-ups. Patients with high REEs at 3-months post-surgery did not lose more TBW than those in the low-REE group at 12-months post-surgery (-30.1 ± 12.8 kg vs. -38.6 ± 14.4 kg; P = 0.155). Similarly, there was no difference in mean TBW reduction between controls in the low- and high-REE groups (P = 0.115). Thus while patients with a high adjusted-REE value at baseline (> 9746.6kJ/day) lost more weight at 3- and 12-months post-GBP, it is plausible that from the third to the 12th month post-surgery, other key drivers of weight loss, particularly the reduction in energy intake are more important in predicting WL. Further research with a larger sample size is required to increase the chances of detecting a true effect.

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Does gastric bypass surgery change body weight set point?

International Journal of Obesity Supplements ◽

10.1038/ijosup.2016.9 ◽

2016 ◽

Vol 6 (S1) ◽

pp. S37-S43 ◽

Cited By ~ 11

Author(s):

Z Hao ◽

M B Mumphrey ◽

C D Morrison ◽

H Münzberg ◽

J Ye ◽

...

Keyword(s):

Gastric Bypass ◽

Body Weight ◽

Bypass Surgery ◽

Gastric Bypass Surgery ◽

Set Point

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Meal-Induced Hormone Responses in a Rat Model of Roux-en-Y Gastric Bypass Surgery

Endocrinology ◽

10.1210/en.2009-1332 ◽

2010 ◽

Vol 151 (4) ◽

pp. 1588-1597 ◽

Cited By ~ 114

Author(s):

Andrew C. Shin ◽

Huiyuan Zheng ◽

R. Leigh Townsend ◽

David L. Sigalet ◽

Hans-Rudolf Berthoud

Keyword(s):

Type 2 Diabetes ◽

Gastric Bypass ◽

Body Weight ◽

Rat Model ◽

Peptide Yy ◽

Gastric Bypass Surgery ◽

Postprandial Glucose ◽

Potential Candidate ◽

Sprague Dawley

Roux-en-Y gastric bypass (RYGB) surgery is the most effective treatment for morbid obesity and remission of associated type 2 diabetes, but the mechanisms involved are poorly understood. The aim of the present study was to develop and validate a rat model for RYGB surgery that allows repeated measurement of meal-induced changes in gut and pancreatic hormones via chronic venous catheters. Male Sprague Dawley rats made obese on a palatable high-fat diet were subjected to RYGB or sham surgery and compared with chow-fed, lean controls. Hormonal responses to a mixed-liquid test meal were examined by frequent blood sampling through chronically implanted jugular catheters in freely behaving rats, 3–4 months after surgery, when RYGB rats had significantly reduced body weight and fat mass compared with sham-operated rats. Hyperleptinemia, basal hyperinsulinemia, and hyperglycemia as well as postprandial glucose intolerance seen in sham-operated, obese rats were completely reversed by RYGB and no longer different from lean controls. Postprandial increases in glucagon-like peptide-1, peptide YY, and amylin as well as suppression of ghrelin levels were all significantly augmented in RYGB rats compared with both sham-operated obese and lean control rats. Thus, our rat model replicates most of the salient hormonal and glycemic changes reported in obese patients after RYGB, with the addition of amylin to the list of potential candidate hormones involved in hypophagia, weight loss, and remission of diabetes. The model will be useful for elucidating the specific peripheral and central mechanisms involved in the suppression of appetite, loss of body weight, and remission of type 2 diabetes.

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