The pulmonary physician in critical care * Illustrative case 8: Acute respiratory failure following lung resection.

CASE HISTORY A 75 year old male smoker of 60 pack-years presented with haemoptysis. Investigation revealed a bronchogenic carcinoma (non-small cell), apparently localised to the right upper lobe. The patient was otherwise well. Routine haematological and biochemical parameters were within normal limits. Spirometry was 2.4/ 3.01 litres (80%/76% predicted) and preoperative arterial blood gas tensions were satisfactory (PaO2 10.7 kPa, PaCO2 5.6 kPa on air). Right thoracotomy revealed extensive malignancy filling the upper lobe and involving the middle lobe at the confluence of the fissures. Histological examination confirmed bronchoalveolar carcinoma and systematic nodal dissection demonstrated N1 disease at station 11. All mediastinal nodes were clear of disease. The patient underwent uncomplicated right pneumonectomy and was extubated shortly afterwards. The morning after surgery the chest radiograph was satisfactory and gas tensions were acceptable (PaO2 13.5 kPa, PaCO2 5.9 kPa using inspired oxygen concentration, FiO2 0.4). However, a repeat chest radiograph the next day revealed alveolar infiltrates in the remaining lung and, by day 3, oxygen saturations had fallen to 85% despite oxygen supplements. The alveolar shadowing progressed despite the use of diuretic and antibiotic treatment and insertion of a mini-tracheostomy. By day 4 the blood gas tensions were PaO2 6.5 kPa, PaCO2 6.4 kPa (FiO2 0.21). The patient was admitted to the intensive care unit and required sedation, endotracheal intubation, and mechanical ventilation the following day. Fibreoptic bronchoscopy and bronchoalveolar lavage were negative for microbiological staining and culture. Electrocardiograms and troponin levels were normal. Pulmonary artery catheterisation showed no evidence of left atrial hypertension. A CT scan of the thorax revealed diffuse ground glass infiltrates throughout the left lung, coalescing into patches of consolidation in dependent areas. The patient remained hypoxic and hypercarbic for 10 days before beginning to improve. He left the intensive care unit 26 days after admission with PaO2 13.5 kPa, PaCO2 5.2 kPa, SaO2 of 99% on 3 litres oxygen administered via nasal cannulae, and subsequently made a complete recovery.