Staphylococcia and severe acute respiratory distress syndrome

A 17-year-old boy with type I diabetes mellitus, was admitted to the intensive care unit with a 7-day history of right ankle contusion that progressed to erysipela, fasciitis and acute respiratory failure (septic embolic pneumonia – blood cultures positive to Staphylococcus aureus). Chest X-ray revealed bilateral infiltrates, the PaO₂/FiO₂ ratio was 150 and there was no evidence of pulmonary congestion. Vancomycin and surgical intervention were initiated and a thoracic computed tomography (CT) scan was performed right after the patient was intubated. The CT revealed gravity-dependent opacities and peribronchiolar patchy infiltrates. A stepwise recruitment maneuver (SRM) with high positive end expiratory pressure (PEEP) levels (25, 30, 35, 40 and 45 cmH₂O) and a fixed pressure control level of 15 cmH₂O was carried out at the Radiology suite, and the PEEP was titrated in order to keep the lung open and to minimize VILI. The CT scan showed that the lung opened with 45 cmH₂O PEEP+15 cmH₂O PCV (60 cmH₂O total), and was kept open with 25 cmH₂O PEEP; the PaO₂/FiO₂ ratio was >350. After 24 hours the PaO₂/FiO₂ ratio worsened and another SRM was performed; the PEEP increased to 29 cmH₂O and the PaO₂/FiO₂ ratio increased to >350. The FiO₂ was decreased to 30%, and after 96 hours the PEEP levels were progressively decreased and pressure support ventilation was initiated. After 10 days of intubation, the patient was weaned from mechanical ventilation and started on hyperbaric oxygen. After 3 days of extubation, the patient was breathing room air with SpO₂ >95%.

The CT scan showed that the SRM is important before increasing PEEP levels. PEEP levels must be set in order to prevent alveolar collapse according to the CT scan or PaO₂/FiO₂ ratio > 350, and it is important to initiate pressure support ventilation as soon as possible in order to prevent critical illness polyneuropathy. In this case we did not observe barotrauma, circulatory failure, ventilator-associated pneumonia, and the intensive care unit length of stay was 12 days. In this severe case of acute respiratory distress syndrome, the SRM with high PEEP levels and PEEP titration according to the CT scan and according to PaO₂/FiO₂ ratio > 350 was effective, and related to a better prognosis.