[Ephedrine reduces the pain from propofol injection]

Propofol is the most frequently used intravenous anesthetic today. One of its side effects is the pain on injection. Various methods such as adding lidocaine, cooling or warming and dilution of the propofol solution have been used for reducing the pain. However, each of these methods comes with a degree of failure. We designed this double-blinded randomized clinical trial to evaluate the effects of ephedrine of the injection pain caused by propofol. Fifty patients, between 20-60 years old and in the ASA physical status I and II, were enrolled in this experimental study and randomly divided into two equal groups. The basal vital signs for all patients were recorded, and 30 seconds prior to the induction of anesthesia, either 70 micro g/kg of ephedrine [study group] or an equal volume of normal saline [control group] was administered without premedication. Then, 20% of propofol was administered to each patient, and the pain intensity was measured and recorded by both the Verbal Rating Scale [VRS; grading 0-3] and Face Pain Scale [FPS; grading 1-6]. The remaining dose of propofol and atracurium were administered. Patients of two groups were similar with respect to age, sex, ASA status, and basal vital signs [P>0.05]. The mean degrees of pain severity, in the study and control group were 0.48 +/- 0.51 and 1.08 +/- 759 by VRS [P = 0.002], and 1.48 +/- 0.586 and 2.04 +/- 0.841 by FPS [P=0.009], respectively. Based on the results of the present study, also supported by other studies, it seems that administration of ephedrine prior to propofol is a suitable method for reduction of pain from propofol injection

[Evaluation of Intravenous ephedrine's effect on shortening the onset time of muscle relaxation of induced by atracurium]

Delayed onset time of neuromuscular blocking is one of the limitations of using nondepolarizing muscle relaxants for facilitation of endotracheal intubation. This double-blinded randomized clinical trial was designed with the presumption that ephedrine can increase cardiac index and muscle blood flow and therefore it may shorten the onset time of muscle relaxation by atracurium. Sixty patients, aged 18-60 yr, with ASA physical status I, II were randomly assigned into two equal groups. Baseline vital signs were recorded and then all patients received intravenous midazolam and fentanyl, as premedication. One minute before induction of anesthesia with propofol and atracurium, the experimental group received intravenous ephedrine 70 micro g/kg and control group received an equal volume of normal saline. Muscle relaxation was assessed by means of peripheral nerve stimulator, based on TOF pattern of stimulation on ulnar nerve. The time interval between atracurium injection and the absence of TOF response [TOF=0] was recorded in all patients. Using SPSS software, data were analyzed by means of student's t-test and Chi-square test. Demographic data and baseline vital signs were similar in both groups [p>0.05]. The mean time taken for onset of relaxation, needed for endotracheal intubation [from atracurium administration to the time of TOF =0], was less in study group compared to control group [185.1 +/- 21.59 vs. 258.43 +/- 20.63 seconds] which was statistically significant [p<0.001]. intravenous injection of ephedrine shortens the onset time of atracurium induced muscle relaxation which is similar to other nondepolarizing muscle relaxants, such as vecuronium and rocuronium

effect of addition of intravenous nitroglycerin to lidocaine for improvement of quality of intravenous regional anesthesia

Disadvantages of intravenous regional anesthesia [IVRA] include slow onset, poor muscle relaxation, tourniquet pain, and rapid onset of pain after tourniquet deflation. In this randomized, double-blind study, we evaluated the effect of addition of nitroglycerine [NTG] to lidocaine for improvement of IVRA. Forty six patients [20-50 yrs] were randomly assigned into 2 equal groups. Under identical conditions, the control group received 3 mg/kg of lidocaine 0.5% diluted with saline, and the study group received an additional 200 microgram NTG. Vital signs and tourniquet pain were measured on the basis of VAS score and recorded before applying tourniquet and 5, 10, 15, 20, and 30 min after administration of anesthetic solution. The onset of sensory and motor block was measured and recorded for all patients. Severity of pain was measured at 5 min, 2, 4, 6, 12, 24, hours after deflation of tourniquet and the total dosage of pethidin injected in the first 24 hours after operation was calculated. Sensory and motor block began more rapidly in study group than control group [2.61 vs. 5.09 and 4.22 vs. 7.04 min., respectively] [p<0.05]. Recovery from sensory and motor block and onset of tourniquet pain were delayed [7.26 vs. 3.43, 9.70 vs. 3.74 and 25 vs. 16.65min., respectively] [p<0.05]. Duration of analgesia after tourniquet deflation was more prolonged and tourniquet pain intensity was lower in study group [p<0.05]. Fentanyl requirement during operation and meperidine used during first postoperative day and pain intensity at 4, 6, 12 and 24hr postoperatively were lower in study group p<0.05. No significant side effect was noted in the patients of both groups. Addition of NTG to lidocaine in intravenous regional anesthesia accelerates the onset of anesthesia and decreases the tourniquet and postoperative pain, without any side effect