Physiologymiddle twist
A 58-year-old man has vomited large volumes each day for nine days, bringing up food eaten the day before. The vomitus contains no bile. He has lost 5 kg, his mouth is dry and his radial pulse is 104/min. Serum sodium is 138 mmol/L, potassium 2.9 mmol/L and chloride 86 mmol/L. Arterial blood is sampled while he lies quietly at rest.
Which one of the following combinations of arterial pH, plasma bicarbonate and arterial carbon dioxide tension (PaCO2) would you expect in this man?