OM (resident, intensivist)

A 54-year-old heavy smoker with a 20-year history of COPD, confirmed by spirometry, and previous gastric ulcer presented to the emergency room with mild mid-epigastric pain, nausea and vomiting evolving over 3 days.

He reported taking a traditional herbal tea made of Retama raetam (white weeping broom) (approximately 1000 mL) which caused subsequent symptom deterioration and acute confusion (figure 1).

On examination, the patient had no fever and was confused with a Glasgow coma score of 13/15. His abdomen was soft. The remainder of the physical examination was unremarkable. Chest X-ray, ECG, CT brain scan and laboratory blood tests were normal. Arterial blood gas (ABG) analysis on room air disclosed severe respiratory acidosis with hypercapnia and high bicarbonate level (pH=7.14, pCO₂=11 kPa, =36 mmol/L) as well as severe hypoxaemia (paO₂=5.4 kPa).

Subsequently, because of a rapid deterioration of the level of consciousness, as assessed by a fall in Glasgow coma score (GCS) to 6/15, the patient required intubation, sedation and mechanical ventilation. His blood pressure and pulse fell substantially soon after he was placed on the ventilator, requiring fluid resuscitation and continuous infusion of norepinephrine (1 mg/h). The patient was then transferred to the intensive care unit (ICU).

In the ICU, he was maintained on volume assist control ventilation with the following settings: tidal volume 420 mL, FIO₂ 50%, positive end expiratory pressure (PEEP) 4 cm H₂O, respiratory rate 14/min and inspiratory time (I)/expiratory time (E) ratio of 1/3. Pupils were dilated and responsive to light. Invasive arterial blood pressure (IABP) was 120/65/80 mm Hg, respectively, for systolic, diastolic and mean IABPs. Oxygen saturation by pulse oximetry was 100%, and heart rate was around 55 bpm. ECG showed sinus bradycardia with no other …