Dexamethasone for prevention of postoperative shivering: a randomized double-blind comparison with pethidine

Postoperative shivering is very common and followed by many problems such as increasing oxygen consumption, blood pressure, intracranial and intraocular pressure, and postoperative pain. Therefore, prevention of shivering is important, especially in elderly and ischemic heart disease patients. The goal of this study was to compare the effect of pethidine [meperidine], dexamethasone, and placebo on prevention of shivering. This double-blind clinical trial study was carried out on 120 patients who were candidates for surgery under general anesthesia. The patients were randomly divided into three groups. Induction and maintenance of anesthesia for all patients were similar. Temperature of patients was measured every 5 min interval. After induction, saline 0.9%, dexamethasone and pethidine were injected to groups a, b, and c, respectively. In recovery, patients were controlled for visible shivering. All data were statistically analyzed by analysis of variance [ANOVA] and Chi-square tests. There were no significant differences among three mentioned groups regarding gender, age, duration of surgery and anesthesia, extubation time, duration of recovery, and basic clinical characteristics. Nineteen cases [47.5%] of placebo group had postoperative shivering, whereas in dexamethasone group only four cases [10%] had shivering and the difference between the two groups was significant. Also in pethidine group, 15 cases [37.5%] had shivering and the difference with placebo group was significant [P value = 0.001]. The present study showed that pethidine and dexamethasone are effective drugs for prevention of postoperative shivering in elective surgery and the effect of dexamethasone in preventing the postoperative shivering is better than pethidine

Comparison of the effects of remifentanil and alfentanil on intraocular pressure in cataract surgery

Anesthesia for ophthalmic surgery requires management of intraocular pressure [IOP] during perioperative period. In an open eye, in conditions such as after traumatic injury or during cataract surgery, IOP increase can lead to permanent vision loss. Administration of narcotics concomitant with anesthetics has the ability to reduce this increase of IOP. This clinical trial aims to compare the efficacy of remifentanil and alfentanil in preventing an increase in IOP after administration of succinylcholine, intubation and during anesthesia. This double-blind clinical trial was conducted on 50 patients undergoing elective general surgery for cataracts. Patients were randomly divided into two groups. Alfentanil [20 microg/kg in 30 s] for group 1 and remifentanil [1 microg/kg in 30 s] for group 2 were injected before induction of anesthesia, and 0.5 microg/kg/min alfentanil for group 1 and 0.1 microg/kg/min remifentanil for group 2 were infused during the anesthesia. Systolic and diastolic blood pressure, heart rate, and IOP from normal eye were measured before the induction, after administration of thiopental and succinylcholine, after tracheal intubation, and 2 min later, and were repeated in 2-min intervals until the end of operation. IOP decreased after injection of anesthetics and remained lower all through the operation in both groups, but IOP decreased after injection of succinylcholine in remifentanil group while it increased in alfentanil group [P<0.05]. Results of this study indicate benefits of both remifentanil and alfentanil in managing IOP after induction and during anesthesia. It seems that remifentanil is better than alfentanil in controlling the IOP after injection of succinylcholine

comparison of alfentanil and remifentanil infusion during anesthesia on post-anesthesia recovery

With consideration the daily increased development of outpatient surgeries and high rate of these surgeries in elderly patients, rapid and safe recovery of patients is necessary. In this clinical trial study, recovery time and nausea and vomiting after the use of two rapid-onset narcotics, Alfentanil and Remifentanil, in elderly patients were evaluated. In this double-blind prospective clinical trial, 40 elderly patients [age above 65 years] candidate to cataract surgery with general anesthesia were studied. The patients were divided randomly into two groups and for first group, 10 microg/kg of Alfentanil was injected and for second group Remifentanil 0.5 microg/kg was injected intravenously during 30 seconds one minute before induction. Both two groups were under general anesthesia with same method and during the anesthesia, first group took infusion of Alfentanil 1 micro g/kg/min and second group took Remifentanil 0.1 micro g/kg/min. In the end of surgery, the time intervals between end of anesthesia drug administration and spontaneous respiration, eyes opening with stimulation, verbal response and discharge of recovery room, also the incidence of complications related to narcotic drugs, especially nausea and vomiting, was recorded. The data were analyzed in SPSS software using descriptive and analytical statistics such as T-test and chi square test. The time of spontaneous respiration in Alfentanil group was 2 minutes and in Remifentanil group was 3.3 minutes, the difference was not statistically significant [P=0.08]. The time of eyes opening with stimulation, verbal response, and discharge of recovery room were not significantly different. During recovery, incidence of nausea and vomiting in Remifentanil group [30% of patients] was significantly more than Alfentanil group [5% of patients] [P=0.045]. Recovery time between Alfentanil and Remifentanil group was not significantly different, but incidence of nausea and vomiting in Remifentanil group was higher than Alfentanil group significantly. It seems that using Alfentanil in the anesthesia for surgical treatment of the elderly people can be preferred