title: Evaluation of liquid ingestion after bariatric surgery.
abstract: BACKGROUND
  Bariatric surgery is an effective treatment for obesity; however, after surgery the patient may have difficulty in swallowing liquid and solid foods.
  
  
  OBJECTIVE
  To evaluate liquid ingestion in patients who had undergone bariatric surgery.
  
  
  METHODS
  We studied 43 volunteers with normal body mass index (BMI) (BMI: 18.5-24.9 kg/m²), 55 subjects with class III obesity (BMI: >40.0 kg/m²), and 48 subjects with bariatric surgery for treatment of class III obesity. The method chosen for evaluation was the water swallowing test. The subjects drank in triplicate 50 mL of water while being precisely timed and the number of swallows were counted.
  
  
  RESULTS
  There was no difference between subjects with normal BMI and subjects with class III obesity. During the first 2 months after bariatric surgery the patients showed an increase in the time needed to drink the entire volume, in the number of swallows, and in the inter-swallow interval, and a decrease in the volume swallowing capacity (volume/swallowing) and swallowing flow rate (volume swallowed/second). After 2 months, the results of the swallowing measurements moved in the direction of normal values.
  
  
  CONCLUSIONS
  Bariatric surgery may cause more intense alterations of liquid bolus swallowing within 2 months after the procedure, which moved to normal values after this time.
authors.affiliation: Department of Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil. rodantas@fmrp.usp.br
authors.forename: Roberto Oliveira
authors.initials: RO
authors.lastname: Dantas
authors.forename: Leda Maria Tavares
authors.initials: LM
authors.lastname: Alves
authors.forename: Rachel de Aguiar
authors.initials: Rde A
authors.lastname: Cassiani
authors.forename: Carla Manfredi dos
authors.initials: CM
authors.lastname: Santos
mesh_terms: D000328:Adult; D000368:Aged; D050110:Bariatric Surgery / Q000009:adverse effects*; D015992:Body Mass Index; D016022:Case-Control Studies; D003679:Deglutition / Q000502:physiology; D003680:Deglutition Disorders / Q000175:diagnosis / Q000209:etiology*; D004326:Drinking / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery*; D013997:Time Factors; D055815:Young Adult