Abstract
Evaporative water loss and urine volume were investigated in 65 healthy adult Sudanese male surgical patients in Khartoum. The mean evaporative water loss per day was found to be 3063 g in the hot dry season and 667 g in the cold dry season. The mean 24-h urine volume was found to be 594 and 1515 ml respectively. There was a significant correlation between evaporative water loss and the air temperature and the effective temperature. These findings support the results reported from other parts of the tropics that the values for evaporative water loss and urine volume quoted for temperate climates are not representative of those encountered in the tropics.