Bi-PAP vs Sham Bi-PAP on Pulmonary Function in Morbidly Obese Patients After Bariatric Surgery

Evangelismos Hospital

Status: Completed

Conditions: Hypoxemic Respiratory Failure; Atelectasis; Pulmonary Disease; Morbid Obesity; Pulmonary Infection; Hypoxemia; Chronic Obstructive Pulmonary Disease (COPD)

Treatments: Device: Sham Bi-PAP; Device: Bi-PAP

Study type: Interventional

Funder types: Other

Identifiers

NCT03438383

142/23-05-2011

Details and patient eligibility

About

The effect of biphasic positive airway pressure (Bi-PAP) at individualized pressures on the postoperative pulmonary recovery of morbidly obese patients (MOP) undergoing open bariatric surgery (OBS) and possible placebo device-related effects (sham-Bi-PAP) were investigated.

Full description

In the present study the effect of Bi-PAP on the postoperative respiratory function and related complications of MOP undergoing OBS through a randomized sham-controlled design was investigated. Bi-PAP was applied at individualized pressures in order to optimize respiratory support and sham Bi-PAP was also used in order to neutralize possible placebo device related effect and researcher related bias.

The investigators hypothesized that the use of Bi-PAP at individualized pressures in MOP undergoing OBS, ameliorates postoperative respiratory function as well as diminishes related pulmonary complications, postoperative pain and duration of hospitalization. Primary endpoints were the difference in pre- and postoperative measurements of certain pulmonary function parameters (forced expiratory volume at one second (FEV1), forced vital capacity (FVC), peak expiratory flow rate (PEFR) and oxygen saturation by pulse oximetry (SpO2) and the incidence of certain pulmonary complications postoperatively (hypoxemia, atelectasis, lower respiratory tract infections). Secondary endpoints were postoperative pain and days of hospitalization.

Enrollment: 48 patients

Sex: All

Volunteers: No Healthy Volunteers

Inclusion criteria

• All patients have been Morbidly Obese (BMI> 40kg/m2) for at least 10 years
• All patients had unsuccessfully tried to lose weight by other non-invasive means.
• All patients enrolled were continuous positive airway pressure (CPAP) and Bi-PAP naïve and had no knowledge about the Bi-PAP apparatus prior to enrollment
• All patients underwent OBS (gastroplasty by Mason or gastric bypass) by the same operating team
• All patients were treated with the same standard anesthetic protocol

Exclusion criteria

• Cardiovascular and pulmonary disease not related to obesity status
• Chronic renal disease
• Patients who were initially enrolled but did not use the allocated device (Bi-PAP or Sham Bi-PAP) for at least 12 h daily were also excluded at a later point.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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48 participants in 2 patient groups

Sham Bi-PAP

Sham Comparator group

Description:

Sham Bi-PAP was applied through nasal mask for 3 days postoperatively. Sham Bi-PAP was created by introducing a "hole" at the connection of the mask with the spiral tube of Bi-PAP. With this modality, also used on previous studies, the applied pressure by sham Bi-PAP was constant and equal to 2 centimeter of water (cm H2O).

Treatment:

Device: Sham Bi-PAP

Bi-PAP

Active Comparator group

Description:

Bi-PAP through nasal mask, at individualized IPAP/EPAP pressures, was applied for 3 days postoperatively. IPAP and EPAP in the Bi-PAP system were individualized for each patient in accordance with accepted values of SpO2, PaCO2, and patient synchronization and tolerability with the device.Individualized setting of pressures in patient group was applied gradually starting with 12/4 cm H2O (IPAP/EPAP) and up to 18/10 (IPAP/EPAP) with consecutive increases of 2 cm H2O.

Treatment:

Device: Bi-PAP