© 2003 Fellowship of Postgraduate Medicine
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A case of reduced consciousness and hypoventilation
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The patient has metabolic alkalosis. Serum chloride is essential for further management. The chloride was measured at <70 mmol/l, the lowest point at which the assay is accurate and was probably considerably lower than this.
Increasing the inspired oxygen has improved the oxygenation; however, the carbon dioxide and bicarbonate have risen further. This is because compensation for metabolic alkalosis involves hypoventilation, leading to respiratory acidosis. The degree of hypoventilation is limited by hypoxia and by providing a higher inspiratory concentration of oxygen a further decrease in minute ventilation has occurred. This has resulted in a rise in carbon dioxide.
This patients alkalosis is due to a loss in hydrochloric acid from the gut during the severe and protracted vomiting. For every hydrogen ion secreted into the gut a bicarbonate ion is released into the serum. Potassium chloride is also lost into the gut. The resulting dehydration and hypokalaemia leads to
Relevant Article
- A case of reduced consciousness and hypoventilation
- A Pandurengan and C M Thorpe
Postgrad. Med. J. 2003 79: 242.[Extract] [Full Text] [PDF]
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