Observations on the effects of drugs used in general anaesthesia for ear operations on renal functions.

The purpose of this study was: 1) to observe the renal effects of atropine and pethidine administered intravenously in premedication, 2) to assess the renal effects of diethyl ether and halothane, 3) to study the effects of respiration on the renal functions in general anaesthesia and 4) to evaluate the antidiuretic action of Octapressin used for infiltration of the field of operation during anaesthesia. The studies on the renal effects of the drugs used in premedication were carried out on 27 patients. The renal effects of general anaesthesia and operation on renal functions were studied in 20 patients divided into 2 groups. Group I comprised of patients under diethyl ether anaesthesia while in group II halothane was used. In both groups subgroups A and B were isolated depending on the type of respiration applied during general anaesthesia (subgroup A -- manually assisted respiration, subgroup B -- spontaneous respiration). In all patients in groups I and II Octapressin was used for infiltration of the field of operation. Its renal effects were assessed on the results of determinations in 5 cases (subgroup II-A) anaesthetized with halothane and receiving manually assisted respiration. These results were compared with those in group III which comprised of 5 patients anaesthetized with halothane who were not given Octapressin infiltrations. The following conclusions have been drawn from these results: 1) Atropine and pethidine administered intravenously in therapeutic doses significantly reduce glomerular filtration. 2) Changes in renal functions observed during general anaesthesia and operation were the result of ADH secretion stimulation and changes in renal haemodynamics. 3) No differences were observed between the renal effects of diethyl ether and halothane which was due, probably, to compensatory renal mechanisms regulating renal circulation and osmotic equilibrium in the organism. 4) No differences were observed also in the renal effects of various method of ventilation used during anaesthesia. 5) Octapressin used in therapeutic doses for infiltration of the operation field had no potentiating effect on the antidiuretic action of general anaesthetic agents.