Introduction: Synchronized independent lung ventilation (SILV) is an effective mode of mechanical ventilation for treating both unilateral and bilateral pulmonary lesions. Oxygenation improves with an increase in the ventilation/perfusion ratio and also diminishes the risk of barotrauma. We describe our broad experience with this technique. Our main objective was to confirm whether SILV is able to improve the alveolar-arterial oxygen difference [P(A-a)O2] of patients with severe adult respiratory distress syndrome (ARDS) in whom conventional mechanical ventilation has not brought about improvement after being used for over 48 hours.
Patients and methods: We carried out a descriptive, open, controlled prospective study of 45 patients with severe ARDS, enrolled from among 68 who underwent treatment with SILV. The most frequent cause of ARDS in our study was multiple trauma. The patients diagnosed of ARDS who did not improve with conventional mechanical ventilation were treated with SILV. Clinical characteristics and mortality are described. APACHE II scores, PAOA-aO2, dynamic distensibility were analyzed before and after SILV. The results of SILV were considered good if PA-aO2 improved at least 30% within 48 hours, with no increase in distensibility.
Results: No complications due to the technique were observed. Twenty-two patients (48.8%) died, 18 as a result of multiple organ failure and only one (4.5%) because of hypoxia. The improvements in APACHE II and (PA-aO2 were statistically significant, while distensibility did not change. The result was defined as good in most cases (n = 34, 83.8%).
Conclusions: SILV is useful for providing ventilatory support when ARDS fails to improve with conventional mechanical ventilation. Clear improvement in respiratory function was observed, with significant decrease in PA-aO2 and no change in distensibility. SILV is a safe technique with few complications and can be managed by the intensive care unit nursing staff.