CPAP at 10 cm H2O during cardiopulmonary bypass does not improve postoperative gas exchange

• Autor(a) principal: Figueiredo,Luciana Castilho de
• Data de Publicação: 2008
• Outros Autores: Araújo,Sebastião, Abdala,Rosângela Cristina S., Abdala,Abrão, Guedes,Cristina Aparecida Veloso
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Journal of Cardiovascular Surgery (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0102-76382008000200010
• topic: Continuous positive airway pressure; Extracorporeal circulation; Pulmonary gas exchange; Cardiac surgical procedures

OBJECTIVE: To compare postoperative (PO) pulmonary gas exchange indexes in patients submitted to myocardial revascularization (MR) with or without the application of continuous positive airway pressure (CPAP) during cardiopulmonary bypass (CPB). METHODS: Thirty adult patients submitted to MR with CPB between March and September 2005 were randomly allocated to two groups: CPAP (n=15), patients that received CPAP at 10 cmH2O during CPB, and control (n=15), patients that didn't receive CPAP. PaO²/FiO2 and P(A-a)O2 were analyzed at four moments: Pre (just before CPB, with FiO2=1.0 ); Post (30min post-CPB, with FiO2=1.0); immediate PO period (12h post-surgery, with FiO2=0.4 by using a Venturi® facial mask) and first PO day (24h post-surgery, with FiO2=0.5 by a facial mask). RESULTS: PaO2/FiO2 and P(A-a)O2 tend to get significantly worst as time elapsed during the postoperative period in both groups, but no differences were observed between them at any moment. When PaO2/FiO2 was subdivided into three categories, a greater prevalence of patients with values between 200 mmHg and 300mmHg were observed in CPAP group only at moment Post (30min post-CPB; p = 0.02). CONCLUSION: CPAP at 10cmH2O administered during CPB, although had lightly improved PaO2/FiO2 at 30 minutes post-CPB, had no significant sustained effect on postoperative pulmonary gas exchange. We concluded that in patients submitted to MR, application of 10 cmH2O CPAP does not improve postoperative pulmonary gas exchange.