The Influence of Midazolam on lntraocular Pressure / 대한마취과학회지

Intraocular tension may be acutely changed by many drugs and by various physiologic events. AN acute rise in intracoular tension may be catastrophic if it occurs when the globenis open and leads to expulsion of contents. Most general anesthetics cause a decrease in intraocular pressure, although a few causes increased intraocular pressure. Midazolam is a 1,4-benzodiazepin derivative synthesized by Walser and Freyer in 1975. Earlier studies with midazolam have demonstrated it efficacy for induction of anesthesia and premedication. It is also desirable to know if all anesthetic agents which produce general anesthesia and which are pharmacologically different affect intraocular pressure in a similar manner. Therefore investigation of the influence of midazolam on intraocular pressure in 25 patients was undertaken at the Department of Anesthesiology, Hanyan University. All patients had no known eye abnormalities. The patients were not premedicated. In all patients the intraocular pressure was measured before induction of anesthesia, after instilling a 0.5% tetracaine into the conjunctival sac. A second reading was taken after induction of midazolam (0.2mg/kg of body weight) and a third after injection of succinylcholine(1mg/kg of body weight) and a fourth after endotracheal intubation. A Schiotz tonometer with a 5.5gm and a 7.5gm weight was used. In addition to the tonometric determination, the blood pressure, pulse rate and respiratory rate were recorded before and after induction of midazolam. An attempt was tried to keep the intraocular pressure changed as many and to minimize the other factors affecting intraocular pressure. To achieve this, supine position and constant gas flow was maintained. Special care was taken to avoid pressure on the patients eye and to maintain a fully patent airway to prevent respiratory disturbances leading to straining and increased venou pressure. Endotracheal intubation was performed with the aid of succinylcholine to avoid cough or laryngospasm. The results of the observation with the above mentioned method were tested by student t-test statistically. Each patient acted as his own control. There was a fall in intraocular pressure in 17 patients among 25 patients(average 1.8mmHg), but no significant change followed by the use of midazoam. The blood pressure variations were between 10 and 40 mmHg, during the course of anesthesia and could not be related to intraocular pressure changes. Intraocular pressure changes had no relation to pulse and respiratory rate variations. This finding indicated that benzodiazepine as a class of drugs have well described muscle relaxant properties that are primarily central(supraspinal)rather than peripheral(myoneural) in action. There was a rise in intraocular pressure in 19 patients among 25 patients, followed by the use of succinylcholine and 23 patients among 25 patients, after endotracheal intubation. According to Feldman and Crawley, diazepam potentiated the myoneural blocking effects of gallamine and antagonizes the effects of succinylcholine. Nevertheless Dretchen demonstrated that the clinical doses of diazepam did not potentiated the muscle relants. Our finding showing no apparent succinylcholine interaction with midazolam are consistent with the finding of Dretche.

Change in Total Serum Potasium, Sodium and Calcium by the Administration of Induction Agents with Succinylcholine / 대한마취과학회지

It is important that the clinical anesthetist pay attention to the interaction of anesthetic induction agents and succinylcholine chloride(S,C,C) on the elctrolyte level especially the plasma potassium ion concentration. For instance succinylcholine chloride has a marked effect upon specific conditions such as severe burns, multiple injury, deabetes insipidus and myopathy. Also secondary plasma changes may bring about non synchronous depolarizing action on the muscle and cause cardiac arrhythmai and even cardiac arrest by the increase of potassium concentration in the plasma. With this in mind the author has randomly selected 30 patients who belong to class l physical status by the classification of the American Society of Anesthesiologist had no abnormal symptoms in respiration, circulation or endocrine and metabolism defects. This paper covers the period from the 10th of April 1979 to the 10th of May 1980 in the Department of Anesthesiology, Hanyang University Hospital. The 30 subjects were divided into 3 groups: a) propanidid with S.C.C. b) thiopental sodium with S.C.C. c) diazepam with S.C.C. The plasma concentration of potassium, sodium and calcium were observed and compared in the pre-induction (control group) and two minute post-induction(study group). The results are follows: 1) The plasma potassium ion concentration showed no any significant changes in the whole group. 2) The plasma sodium and calcium ion concentration also showed no any significant changes in the whole group.

Four Cases of Intubation Granuloma / 대한마취과학회지

Traumatic granuloma of the larynx is a localized inflammatory response to the loss of mucosa caused by laryngeal trauma. Endotracheal intubation is the most common cause of traumatic granuloma. The granuloma arises from the vocal process of the arythenoid. Recently we experienced four cases of laryngeal intubation granuloma in Hanyang Medical Center. The microhistologic study confirmed granulomatous polyps of the larynx.