Effect of althesin (CT-1341) on thyroid-adrenal function in man

Althesin infusions for maintenance of anaesthesia

The intravenous anaesthetic Althesin may be administered by continuous intravenous infusion for maintenance of general anaesthesia, sedation in patients in intensive care units or during investigational procedures. Published reports of experience with this technique are reviewed, with particular attention to the rates of administration employed and the influence of other anaesthetics and analgesic agents used concurrently.

Rapid decrease in plasma-triiodothyronine during surgery and epidural analgesia independent of afferent neurogenic stimuli and of cortisol

Changes in circulating triiodothyronine (T3), thyroxine (T4), binding of thyroid hormones to plasma proteins (resin-T3 test), cortisol, and glucose were evaluated in sixteen patients undergoing abdominal hysterectomy. In eight of the patients afferent neurogenic impulses from the surgical area were blocked during and after operation by epidural analgesia. These patients were pain-free, and the normal stress-induced increase in cortisol and glucose was abolished. During epidural analgesia and general anesthesia plasma-T3 fell rapidly and values in the hypothyroid range were found 6 hours after skin incision. Similarly, an increase in the resin-T3 test reflected decreased binding of T3 to plasma proteins. Plasma-T4 decreased slightly during surgery and epidural analgesia (as it does when other anaesthetics are given), but increased during general anaesthesia. These results indicated that the alterations in thyroid hormones and their binding to plasma proteins after surgery are not caused by a stress-induced increase in plasma-cortisol or by neurogenic afferent stimuli from the surgical area, factors which are both known to affect concentrations of other hormones.