The reported incidence of adult respiratory distress syndrome (ARDS) in patients undergoing open heart surgery with cardiopulmonary bypass (CPB) is 0.4-2.5% and this is associated with a high mortality rate (up to 68.4%) [1-4]. In the present observational study we examined the incidence of ARDS in 1157 adult patients of mean ± SD age 64.8 ± 9.7 yr who underwent off-pump myocardial revascularization during a 3½-yr period (February 2000-August 2004) in Henry Dunant Hospital, Athens, Greece. The majority of patients (86%) were males with a mean preoperative left ventricular ejection fraction 4 ± 9%. Ninety-four per cent of the studied patients underwent elective surgery.
Patients were defined to have ARDS if they had all of the following: (a) severe hypoxaemia, as defined by a PaO2/FiO2 ratio <200 mmHg; (b) presence of bilateral lung infiltrates on the chest radiograph; (c) pulmonary arterial wedge pressure of 18 mmHg or no clinical evidence of heart failure or increased left atrial pressure if no wedge pressure measurements were available; (d) absence of chronic obstructive pulmonary disease or other chronic pulmonary disorders and (e) invasive mechanical ventilation [5,6].
The incidence of ARDS during hospitalization was 2/1157 (0.17%). The two patients who developed ARDS were males. One developed this complication during multiple organ failure and septic shock and finally died, while the other developed ARDS during the first postoperative hours with no evident predisposing factors and was ultimately discharged from the intensive care unit (ICU) and hospital in good condition.
In conclusion, we found a lower incidence of ARDS in patients undergoing off-pump myocardial revascularization compared to historical controls of patients undergoing open heart surgery by means of CPB circuit. Our results need to be verified by studies using comparative methodology.
M. E. Falagas
1Intensive Care Unit, Henry Dunant Hospital, Athens, Greece
2Department of Cardiac Surgery, Henry Dunant Hospital, Athens, Greece
3Infectious Diseases Clinic, Henry Dunant Hospital, Athens, Greece
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