Inspiratory Muscle Training After Gastroplasty

• Maximum static respiratory pressures [ Time Frame: post-operative days 2, 7, 14, and 30 ] [ Designated as safety issue: No ]
  This measurement was made at mouth level by using a properly calibrated manovacuometer (GERAR ®, São Paulo, Brazil), with graduation ranging from 0 to ± 300 cmH2O, connected to a rigid plastic tube.
• Inspiratory muscular endurance test [ Time Frame: post-operative days 2, 7, 14, and 30. ] [ Designated as safety issue: No ]
  This measurement was performed by using the Threshold® IMT device (Health Scan Products, USA), at 80% maximal inspiratory pressure, in sitting position.
• Spirometric measurements [ Time Frame: post-operative days 2, 7, 14, and 30. ] [ Designated as safety issue: No ]
  Spirometry was performed according to norms of the American Thoracic Society (ATS) (1994)19 by using a previously calibrated spirometer (Respiradyne II Plus®, Sherwood Medical, St. Louis, USA).

• Maximum static respiratory pressures [ Time Frame: post-operative days 2, 7, 14, and 30 ] [ Designated as safety issue: No ]
• Inspiratory muscular endurance test [ Time Frame: post-operative days 2, 7, 14, and 30 ] [ Designated as safety issue: No ]
• Spirometric measurements [ Time Frame: post-operative days 2, 7, 14, and 30. ] [ Designated as safety issue: No ]

The purpose of this study is to assess the effect of post-operative inspiratory muscle training on muscle strength and endurance in patients with obesity submitted to gastroplasty.

Gastroplasties, like other major abdominal surgeries, induce mechanical changes in the lungs and decreases of the respiratory muscle strength in the post-operative periods. Depending on the occurrence of pre-existing disturbs, obese patients may exhibit severe declines of respiratory function after these surgeries.

Post-operative respiratory physiotherapy is a valuable intervention, involving a set of techniques aimed to expand pulmonary volumes and to improve arterial oxygenation, leading to decreases on the development of atelectasis and pneumonias. It induces faster recovery of respiratory function and reduction of lung complications, what may be particularly important in high-risk patients like over-weighted subjects.

There are scanty data about the role of respiratory muscle training in the post-operative period. This is particularly true regarding inspiratory muscle training of obese patients submitted to gastroplasties.

• Device: inspiratory muscle training
  This daily respiratory exercise was performed from the 2nd day following surgery by using a linear pressure resistance device (Threshold ® IMT - Health Scan Products; USA)was initially set at 40% of the maximal inspiratory pressure, obtained in the 2nd post-operative day, being adjusted to every new maximal inspiratory pressure measurement.
  Other Name: respiratory training
• Device: control group
  In placebo muscular training the daily respiratory exercise was performed from the 2nd day following surgery by using a linear pressure resistance device (Threshold ® IMT - Health Scan Products; USA)no load until the 30th post-operative day.

• Placebo Comparator: control group
  In placebo muscular training group the respiratory exercise was used a linear pressure resistance device (Threshold ® IMT - Health Scan Products; USA) no load.
  Intervention: Device: control group
• Active Comparator: trained group
  In trained group the respiratory exercise used a linear pressure resistance device (Threshold ® IMT - Health Scan Products; USA)the load was initially set at 40% of the maximal inspiratory pressure.
  Intervention: Device: inspiratory muscle training

• Christensen EF, Schultz P, Jensen OV, Egebo K, Engberg M, Grøn I, Juhl B. Postoperative pulmonary complications and lung function in high-risk patients: a comparison of three physiotherapy regimens after upper abdominal surgery in general anesthesia. Acta Anaesthesiol Scand. 1991 Feb;35(2):97-104.
• Dronkers J, Veldman A, Hoberg E, van der Waal C, van Meeteren N. Prevention of pulmonary complications after upper abdominal surgery by preoperative intensive inspiratory muscle training: a randomized controlled pilot study. Clin Rehabil. 2008 Feb;22(2):134-42. Epub 2007 Dec 5.
• Casali CC, Pereira AP, Martinez JA, de Souza HC, Gastaldi AC. Effects of inspiratory muscle training on muscular and pulmonary function after bariatric surgery in obese patients. Obes Surg. 2011 Sep;21(9):1389-94.

Inclusion Criteria:

• gastroplasty patients presenting body mass index (BMI) ≥ 35 kg/m2;
• weighting ≤ 60 kg/m2;
• capable of fulfilling the experimental protocol.

Exclusion Criteria:

• acute or chronic pulmonary disease;
• smoking;
• post-operative mechanical ventilation for more than 48 hours;
• presence of lung complications;
• need for surgical re-intervention during the study period.