Abstract

1. Cardiorespiratory function before and after chest physiotherapy in mechanically ventilated patients with post-traumaticrespiratory failure Chest physiotherapy (CPT) is used frequently in the ICU, but there is little available information that quantifies its effect on cardiac or respiratory function. Nineteen mechanically ventilated patients with posttraumatic respiratory failure were studied before, immediately after, and 2 hour after CPT was used to manage secretion retention. Cardiac index was unchanged, but there was an immediate decrease in intrapulmonary shunt, followed 2 h later by an increase in lung/thorax compliance. We did not find the reduced cardiac output reports by others. The reasons for this may include use of different CPT techniques, a young patient population (mean age 32.4 yr), and mechanical dilation with positive end-expiratory pressure. CPT did not produce the deleterious cardiopulmonary changes associated with bronchoscopy, and a reduced retention lung secretions without producing hypoxemia. Intrapulmonary shunting and long/thorax compliance were significantly improved, and the long-term clinical effect of these changes is unknown. Abstract Colin F Mackenzie, MB, Ffarcs, CHB; Baekhyo Shin, MD Critical Care Medicine, Vol 13, No.6, pg 483 – 485 (1985) Background/Introduction 19 Subjects involved The mean age of the patient was 32.4 ± 14.4 (SD) yr. Twelve were males. All have suffered trauma and average of 4.4 days earlier and were interrelated because of respiratory failure. Ventilation, which was initiated at least six hours before the study began, was controlled by volume preset ventilator within mean inspired oxygen fraction (FIO2) of 0.45 ± 0.1, and an average tidal volume of 11.5 ml/kg. All patients were sedated with morphine and diazempam in ventilated with a mean positive end expiratory pressure (PEEP) of 9 cm H2O ( range 5 to 18). The indications for CPT included secretion retention with segmental or platelike atelectasis (11 patients), lung contusion (six patients), and adult respiratory distress syndrome (two patients). The area of the lungs densities were identified on an anteroposterior (AP) portable chest x-ray taken within the four hours before CPT. During CPT, the patient’s was positioned to allow gravity assisted drainage of the bronchus of the affected lobe or segment. Manual percussion and vibration of the chest were directed in the area of the lung involvement by a physiotherapist Measurement made 20 mins before, immediately after, and 2 hours after chest physical therapy Measurements include – Arterial and pulmonary gases, total lung thoracic compliance, cardiac output, heart rate, and intrapulmonary shunt fraction Subjects Cardiac index (CI), arteriovenous oxygen difference (C[a-v]O2) and oxygen consumption delivered from the product of CI and C[a-v]O2were unchanged by the CPT (Table 1). Left and right ventricular stroke work indices remained the same Qsp/Qt significantly decreased immediately after CPT, in comparison to values obtained before and 2 hours after CPT. The greatest decrease in Qsp/Qt was from 36.3% to 16.5% and 13 patient showed a fall in Qsp/Qt immediately after therapy. There was a significant overall increase in total CT two hours after CPT 11 patients showed a rise in CT immediately after and two hours after CPT The greatest CT rise was from 32 to 51 ml/cm H2O, while the greatest CT decrease was from 48 to 36 ml/cm H2O. I The mean values of cardiorespiratory function for the 11 patients with atelectasis were not clinically or statistically different from those of the six patients with contusions. Results Article 1 – Evidence Support for the Side Lying position – The use of the side lying is recommended for improving oxygenation in the acute respiratory failure patient with unilateral long involvement (Grade A). The affected lung should be superior. However, sideline is associated with certain hemodynamic risk, especially in patients with moderate right ventricular dysfunction. Support for the Prone Position – the prone position is recommended for improving oxygenation in ventilated patients with acute respiratory failure, especially acute respiratory distress syndrome. The prone position is associated with minimal risk and no residual complications. Support for the Semi Recumbent Position – there is, at present, only one piece of Level V evidence to suggest that the semi recumbent position would not improve oxygenation in acute respiratory failure. Pong Wong, W. (1999). Use of body positioning in the mechanically ventilated patient with acute respiratory failure: Application of Sackett's rules of evidence. Physiotherapy Theory and Practice, 25-41. Article 2 – Evidence This article supports the use of the prone position in mechanically ventilated patients with severe acute respiratory failure. After one hour in the prone position, improvements in PaO2/FlO2 by 20 mmHg or war was considered a positive response. 25 had a positive response (78%), and were referred to as responders. Among the seven nonresponders, two did not tolerate the prone position and returned to supine before the end of the four hour trial. In 10 the 23 responders (43%) who completed the four hour prone trial, the PaO2/FlO2 returned to the starting value when the patient was repositioned in supine. In 13 of the 23 (57%) improvements persisted when returned into the supine position. Chatte, G., Sab, J. M., Dubois, J. M., & Sirodot, M. (1997). Prone Position in Mechanically Ventilated Patients with Sevre Acute Respiratory Failure. American Journal of Respiratory and Critical Care Medicine, 473-478. Summary Chest physical therapy techniques such as percussion, chest vibration, suctioning, and postural drainage are supported by the literature. In regards to patients who have suffered from acute respiratory failure and have the need for mechanical ventilation, postural drainage seems to be the most supported technique in the literature. Purpose Chest PT includes postural drainage, percussion, chest wall vibration, and suctioning Commonly used in the ICU, some question it effectiveness Bronchoscopy, an alternative therapy for removal of retained secretions, is associated with airway trauma and cardio respiratory dysfunction This study objectively assesses the cardiorespiratory effects of CPT in intensive care patients requiring mechanical ventilation for respiratory failure. By David Ren Peterson , SPT