Metabolism
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Life-threatening acidosis in an alcoholic - and in a hunger striker given intravenous glucose
PC is a 50 year old man, 174 cm tall and weighing 105 kg. He is an engineer, and works on secondment in one of the strict Islamic states in the Gulf, where alcohol is prohibited.
At the beginning of August he returned to England for his annual leave. According to his family, he behaved as he usually did when on home leave, consuming a great deal of alcohol and refusing meals. He was known to be drinking 2 litres of whiskey, two or three bottles of wine, and a dozen or more cans of lager each day; he refused most meals and his solid food consisted mainly of sweets and biscuits.
On September 1st he was admitted to the Emergency Department of University College Hospital, semi-conscious, and with a rapid respiration rate (40 /min). His blood pressure was 90/60 and his pulse rate was 136 /min. His temperature was normal (37.1 °C). Emergency blood gas analysis revealed severe acidosis: pH 7.02 and base excess -23.
(The base excess is the amount of acid required to return blood pH to the normal range of 7.35 - 7.45 - a negative base excess indicates acidosis)
Why do you think he was breathing rapidly?
The usual response to acidosis is to increase the rate of breathing, so as to expel carbon dioxide, and so shift the equilibrium below to the left, lowering the hydrogen ion concentration in the bloodstream, and so raising plasma pH.
He was transferred to ITU and given intravenous bicarbonate.
Why do you think was he given intravenous bicarbonate?
Providing bicarbonate will permit the equilibrium above to shift to the left, providing carbon dioxide to be exhaled, and so raising plasma pH.
His pulse rate remained high, and his blood pressure low, so emergency cardiac catheterisation was performed; this revealed a cardiac output of 23 litres /min (normal 4 - 6). A chest X-ray show significant cardiac enlargement.