Reversal Of Muscle Relaxation Research Articles

Reversal of fentanyl-induced narcotic depression with naloxone following general anaesthesia.

To study the need for and mode of naloxone reversal after liberal use of fentanyl during anaesthesia, a fixed‐dose schedule of fentanyl (mean 6.5 μg/kg/h) was applied intraoperatively to 60 patients, randomly divided into four treatment groups. After surgery and reversal of muscle relaxation, end‐tidal CO2 was allowed to rise to 8% by manually assisted ventilation. Thereafter, 0.04 mg increments of naloxone were given i.v. every 3 min until spontaneous respiration maintained ETco2 below 8% (group I) or below 6.5% (group II). After similar intravenous reversal to that in groups I or II, an additional intramuscular dose of naloxone, identical to that given i.v., was given to groups III and IV after awakening from nitrous oxide.If ETco2 remained above 6.5%, mean spontaneous minute ventilation was lower than before anaesthesia and significantly (P<0.05) less than if ETco2 had decreased below that value. This difference had disappeared 45 min postnal‐oxone. Arterialized venous Pco2 showed normocapnia (6.0 kPa) in patients with ETco2 <6.5%, hut slight hypercapnia (6.6 kPa) in patients with ETco2>6.5% after intravenous naloxone. After 15 min, the patients with additional intramuscular naloxone had significantly (P<0.05) lower values of Pco2 than those with intravenous naloxone only.Postoperatively, a positive correlation (R = 0.35) between the total dose of naloxone and pain intensity could be demonstrated (P<0.01). As acute postoperative pain could not be avoided after naloxone reversal to normoventilation, titration of naloxone after liberal use of analgesics is recommended with the help of capnography, until an acceptable ETco2 of about 7% is maintained.

THE EFFECT OF DIAZEPAM AND LORAZEPAM ON AWARENESS DURING ANAESTHESIA FOR CAESARIAN SECTION

One hundred-and-eighty-three patients having general anaesthesia for Caesarian section were given lorazepam or diazepam intravenously immediately following delivery. The incidence of unpleasant recall was comparable with the reports of other workers. There was no evidence of a specific retrograde amnesic effect by either drug. Neither agent appeared to affect cardiovascular stability, uterine contraction, the reversal of muscle relaxant or the time to recovery of protective reflexes. The patients tended to be drowsier after lorazepam but as safe as after diazepam so far as circulation, respiration and protective reflexes were concerned.

Early extubation after coronary artery bypass graft surgery

Data were collected on the postoperative respiratory courses of two groups of patients following cardiac surgery: one group of 31 patients under typical management for 1973, and a second group of 72 patients from 1975–1976 representing our current management regimen. The patients in the 1973 group were allowed to wake up passively before our seeking extubation criteria. Almost half of these were extubated in the period 15 to 20 hours after admission to the ICU, i.e., the morning after surgery, and 29% were discharged from the ICU within 48 hours of admission. The patients in the 1975–1976 series had pharmacological reversal of muscle relaxants and somnolence following admission to the ICU, when their condition was shown to be stable by clinical and laboratory assessment. Criteria for extubation were then sought. Within 5 hours of ICU admission, 62.5% of the patients were extubated and almost 50% of the patients were discharged from the ICU within 24 hours. No patient in either series required reintubation, and there were no complications due to the early extubation and ICU discharge of patients in the 1975–1976 series. We believe that early extubation of patients whose postoperative course is otherwise uncomplicated following cardiac surgery allows rapid mobilization and progress to the intermediate care areas without introducing undesirable sequelae.

Integrity of Intestinal Anastomoses Following Muscle Relaxant Reversal With Neostigmine

Integrity of Intestinal Anastomoses Following Muscle Relaxant Reversal With Neostigmine

Timing of Atropine and Neostigmine in the Reversal of Muscle Relaxants

The antimuscarinic effects of atropine were studied in 46 patients to whom neostigmine had been given after operation to reverse the action of a muscle relaxant. Neostigmine was given to alternate patients three minutes after, or together with, atropine, and the effects of the two procedures were compared by measuring the secretions which collected in the buccal and oropharyngeal cavities and observing the heart rate.It was found that the glands of the oral cavity were stimulated to a greater extent when neostigmine was given with atropine than after atropine. Any dose of atropine sufficient to inhibit peristaltic movements of the bowel is more than enough to block completely secretion by the salivary glands, and the appearance of some secretion in all cases after the administration of neostigmine suggests that the bowel was at liberty to react to the neostigmine in every case, but perhaps particularly so when atropine and neostigmine were given mixed. The integrity of an anastomosis of the bowel could be endangered by vigorous peristalsis in the early postoperative period.Electrocardiograms in about half the patients from each group confirmed earlier work that the muscarinic effects of neostigmine on the heart can be prevented by giving the atropine either before or together with the neostigmine.