[Water diuresis during methohexitone anaesthesia. Studies in chronically instrumented dogs (author's transl)].
Seven chronically prepared dogs (electromagnetic flow transducers around the pulmonary and left renal artery, left atrial catheter) maintained on a controlled sodium and water intake were studied. About 20 h after the last intake of food and water, the effects of i.v. methohexitone (initial dose: 6.10 +/- 0.84 mg/kg bw; sustaining infusion: 0.34 +/- 0.10 mg/min.kg bw) on renal excretion of sodium, potassium, urea and water as well as on several haemodynamic values were investigated over a period of 60 min (MP) after a control period (CP) of 60 min in the unanaesthetized state. In 18 of 19 experiments water diuresis (U/Posm less than 1) was observed between 20 and 40 min after starting the administration of methohexitone. Urine volume increased from 44 +/- 21 microliter/min.kg bw (CP) to 104 +/- 62 microliter/min.kg bw (MP).I.v. administration of arginine-vasopressin (ADH) completely abolished water diuresis. During MP, there was a decrease in cardiac output (-11%), stroke volume (-36%) and left atrial pressure (-27%), heart rate increased (+ 43%). Mean arterial blood pressure and renal blood flow did not change. It is assumed-as plasma osmolality did not change-that the central release of antidiuretic hormone is suppressed by methohexitone.
D000758:Anesthesia; D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D004231:Diuresis / Q000187:drug effects*; D004285:Dogs; D004336:Drug Antagonism; D005260:Female; D006325:Heart Atria; D006339:Heart Rate / Q000187:drug effects; D007668:Kidney / Q000098:blood supply; D008723:Methohexital / Q000494:pharmacology*; D009318:Natriuresis / Q000187:drug effects; D011188:Potassium / Q000652:urine; D012039:Regional Blood Flow / Q000187:drug effects; D014508:Urea / Q000652:urine; D014867:Water / Q000378:metabolism
D014867:Water; D001127:Arginine Vasopressin; D014508:Urea; D008723:Methohexital; D011188:Potassium
Wasserdiurese während Methohexitalnarkose. Untersuchungen an chronisch instrumentierten Hunden.