• hypercapnia

A 64 year old woman was brought by ambulance to the accident and emergency department. She had been referred by her GP because of increasing dyspnoea, cyanosis, and lethargy over the previous four days. On arrival of the ambulance crew at her home she was noted to be tachycardic and tachypnoeic (respiratory rate 36/min) with a GCS of 5 (E 3, M 1, V 1). She was given oxygen at 6 l/min via a Duo mask, and transferred to hospital.

The patient arrived at the accident and emergency department 18 minutes later. In transit, there had been a clinical deterioration. The GCS was now 3 and the respiratory rate 4/min. Oxygen saturation, as measured by a pulse oximeter was 99%. The patient was intubated and positive pressure ventilation started. Arterial blood gas measurements taken at the time of intubation were consistent with acute on chronic respiratory failure (fig 1).

Further …