12th November 2021

A 65-year-old female presents to the emergency department with a fever that has lasted a few days

A 65-year-old female presents to the emergency department with a fever that has lasted a few days, shortness of breath and yellow-coloured sputum with rusty red streaks in it. Her room air oxygen saturation is at 87%. An ABG is performed:

• pH: 7.56 [Reference Range: 7.35-7.45]
• PCO2: 2.8 kPa [Reference Range: 4.7-6.0 kPa]
• PO2: 14.3 kPa [Reference Range: 10.6-13.3 kPa]
• HCO3- (Bicarbonate): 22 mmol/L [Reference Range: 22-28 mmol/L]

Describe the acid-base disorder and its underlying cause.

Select the SINGLE most appropriate option from the list below. Select ONE option only.