Effect of halothane, nitrousoxide anesthesia and surgery on plasma thyroid-stimulating hormone [TSH] levels in man

The present study was undertaken to determine the effect of halothane, nitrous oxide and surgery on plasma thyroid-stimulating hormone [T.S.H.] in 20 patients by utilising a radio-immuno assay technique. Measurements of serum thyroid levels were performed simultaneously. The study demonstrated that neither halothane, nitrous oxide anaesthesia, nor surgery influenced appreciably the plasma T.S.H. concentration. However, serum thyroxine level in the halothane group increased significantly, though no significant variation in serum thyroxine level was detected in the nitrous oxide group. These data would suggest that T.S.H. appears to play little role in the control of serum thyroxine level under the stress of anaesthesia and surgery in man

effects of acid-base balance and electrolyte disturbance in cases of late intestinal obstruction on neuromuscular blockade

The effects of changes in the acid base balance and electrolytes on the degree of neuromuscular blockade were studied on 60 adult patients undergoing gastrointestinal surgery. The cases included 30 normal patients and 30 with late intestinal obstruction. For the relaxation during surgery, three types of non-depolarizing muscle relaxants [d-turbocurarine, flaxedil and pancuronium] were used. A peripheral nerve stimulator was used to assess the degree of neuromuscular block. The study showed that metabolic acidosis and hypokalemia let to prolongation of the peripheral effects of three types of non-depolarizing muscle relaxants used with varying degree of affection. This was evidenced by decreased latency, increased time to return to the pre-relaxant response after reversal, and marked prolongation in the recovery time. The study showed that pancuronium is the drug of choice in late cases of intestinal obstruction, being easily reversed and not greatly affected by electrolytes and acid-base disturbances