A guide to the rate of non-renal water loss from patients with burns

Abstract Measurements of the rate of water loss by evaporation have been made in 21 patients with widely differing burned areas treated by the exposure method. Sensitive scales have been used to measure the reduction in body weight over 30-minute periods. The water loss has been expressed as ml. lost per cm. 2 of burned area per day. The patients with mainly full-thickness skin loss burns consistently lost an average of 0·35 ml. of water per cm. 2 of burned area per day during the first week after burning, and a relatively steady loss of 0·30 ml. per cm. 2 per day during the subsequent 2 weeks. The patients with mainly partial thickness skin loss burns showed an initially high loss of 0·45 ml. per cm. 2 per day, decreasing to 0·30 ml. per cm. 2 per day during the second week and 0·25 ml. per cm. 2 per day during the third week after burning. These rates of water loss appeared to be unaffected by environmental temperatures between 22 and 32°C and relative humidities which varied between 20 and 70 per cent. The rate of water loss of patients treated by other than the exposure method may be different.