Positive Expiratory Pressure With Blow-bottle Device Versus EPAP After Postoperative Cardiac Surgery

Cardiac surgery is a recommended therapeutic option as a form of secondary prevention for the treatment of cardiovascular diseases, but may present postoperative alterations such as reduction of pulmonary volumes and flows, impairment in gas exchange and increase in the rate of pulmonary complications. The use of positive pressure may reduce these complications. Objective: To evaluate the efficacy of positive expiratory pressure (PEP) in the blow-bottle device compared to expiratory positive airway pressure (EPAP), both associated with conventional physiotherapy, and conventional physiotherapy in the pulmonary function in postoperative cardiac patients through a randomized clinical trial. Methods: The study was approved by the Research Ethics Committee of the Hospital de Clínicas of Porto Alegre (CAEE: 70213617.6.0000.5327). Patients undergoing cardiac surgery were randomized into three groups: positive expiratory pressure with blow-bottle device associated with conventional physiotherapy (G1), positive expiratory pressure in the airways with unidirectional valve associated with conventional physiotherapy (G2), and the third group only the conventional physiotherapy of HCPA cardiac intensive care unit (G3). Initially, an evaluation was performed through spirometry, manovacuometry, radiological changes in the preoperative period, prior to the interventions (immediate postoperative) and on the third postoperative day, immediately prior to cardiac intensive care unit discharge. Pulmonary complications were assessed on the third postoperative day, and length of stay (at the Intensive Care Unit and hospital) were recorded untill discharge.

Cardiac surgery is a recommended therapeutic option as a form of secondary prevention for the treatment of cardiovascular diseases, but may present postoperative alterations such as reduction of pulmonary volumes and flows, impairment in gas exchange and increase in the rate of pulmonary complications. The use of positive pressure may reduce these complications. Objective: To evaluate the efficacy of positive expiratory pressure (PEP) in the blow-bottle device compared to expiratory positive airway pressure (EPAP), both associated with conventional physiotherapy, and conventional physiotherapy in the pulmonary function in postoperative cardiac patients. Methods:This is a randomized clinical trial, with patients in postoperative cardiac surgery. On the first day of postoperative, the patients will be randomized into three groups: 1 group that will receive positive expiratory pressure with blow-bottle device associated with conventional physiotherapy; 2- group that will receive positive expiratory pressure in the airways with valve unidirectional therapy associated with conventional physiotherapy; 3- group that will only receive conventional physiotherapy. The intervention of the positive expiratory pressure with blow-bottle device group will consist of exercise with a blow-bottle device of 10 cm high; the positive expiratory pressure in the airways group, exercise with unidirectional positive expiratory pressure valve (10cmH2O). Both the groups will perform three sets of 10 repetitions per day, by the third day of PO. The third group will receive conventional physiotherapy of intensive care unit. The outcomes evaluated will be: pulmonary function (primary), respiratory muscle strength, pulmonary complications, radiological changes and length of stay (at the Intensive CareUnit - ICU - and hospital). Assessment of pulmonary function, muscle strength and radiological changes will be performed in the preoperative period, prior to the interventions and on the third postoperative day, immediately prior to discharge of cardiac intensive care unit. Pulmonary complications and ICU length of stay will be recorded after discharge from intensive care unit cardiac. The length of hospital stay was recorded after hospital discharge.

Eligibility Criteria:
Inclusion Criteria:

Elective cardiovascular surgery of:

coronary artery bypass graft surgery alone

coronary artery bypass graft surgery combined with aortic valve surgery

coronary artery bypass graft surgery combined with bicuspid valve surgery

coronary artery bypass graft surgery combined with tricuspid valve surgery

Aortic valve surgery

Bicuspid valve surgery

Tricuspid valve surgery

All on spontaneous ventilation or with supplemental oxygen support.

Exclusion Criteria:

Patients with hemodynamic instability (heart rate\> 120bpm, clinically important hypotension - vasopressor dose ≥ 0.1mcg / kg / min)

Cardiac arrhythmia

Heart transplantation

Angina at rest and/or minor efforts

Mechanical ventilation for more than 24 hours

Re-hospitalized patients with decompensated heart failure

Noninvasive mechanical ventilation

Non-collaborative and with cognitive inability to understand the procedures

Reintubated patients

Re-operated patients

In order to perform the pulmonary function test, patients may not present the following contraindications:

hemoptysis

recent angina

retinal detachment

hypertensive crisis

pulmonary edema

thoracic aortic aneurysm

In order to perform the respiratory muscle strength test, patients may not present the following contraindications:

acute myocardial infarction

recent unstable angina

severe and uncontrolled systemic arterial hypertension

aortic aneurysm

pneumothorax

pleurocutaneous or pulmonary fistulas

surgery or recent trauma to the upper airways, chest or abdomen

abdominal hernia

acute middle ear problems

glaucoma or retinal detachment

hydrocephalus

meningocele

neurological processes that favor the choking of tonsils

general state of physical or mental impairment that impedes the patient's collaboration.