Study objectives: Patients who undergo surgical repair of thoracoabdominal aortic aneurysms have a high risk for the development of respiratory complications, which cause significant postoperative morbidity and prolong hospitalization, compared to patients who undergo other types of surgery. We studied whether prophylactic noninvasive application of nasal continuous positive airway pressure (nCPAP) administered via a facemask immediately after extubation may reduce pulmonary morbidity and shorten the length of hospitalization.
Design: Prospective randomized clinical trial.
Setting: Surgical ICU of a university hospital.
Patients: Fifty-six patients following elective prosthetic replacement of the thoracoabdominal aorta, of whom 6 patients were excluded because they had received prolonged mechanical ventilation.
Interventions: Following extubation in the ICU, nCPAP was applied for 12 to 24 h at an airway pressure of 10 cm H2O to patients in the study group (n = 25). Subjects in the control group (n = 25) received standard treatment including intermittent nCPAP (10 cm H2O for 10 min) every 4 h.
Measurements and results: In the study group, nCPAP was applied for a mean (+/- SD) duration of 23 +/- 3 h at an airway pressure of 10 +/- 1 cm H2O, which improved pulmonary oxygen transfer without altering hemodynamics (ie, heart rate, mean arterial BP, and central venous pressure). The application of nCPAP was associated with fewer pulmonary complications (Pa(O2)/fraction of inspired oxygen [F(IO2)] <100, atelectasis, pneumonia, reintubation rate) compared to the control group (7 of 25 patients vs 24 of 25 subjects, respectively; p = 0.019). The mean duration of intensive care treatment tended to be shorter in the study group compared to the control group (8 +/- 1 vs 12 +/- 2 days, respectively; difference not significant), while the mean length of hospital stay was shorter with nCPAP therapy (22 +/- 2 vs 34 +/- 5 days, respectively; p = 0.048).
Conclusions: The prophylactic application of nCPAP at airway pressures of 10 cm H2O significantly reduced pulmonary morbidity and length of hospital stay following the surgical repair of thoracoabdominal aortic aneurysms. Thus, it can be recommended as a standard treatment procedure for this patient group.