Neurohumoral effect of xenon

Clinical trials were carried out in 44 patients during cholecystectomies. The patients were divided into 2 groups (22 pts each) receiving (1) Xe:O2 (70:30) or (2) N2O:O2 (70:30) + phentanyl (0.1 ml boluses every 20 min). Neurohumoral parameters (ACTH, hydrocortisone, STH, prolactin, aldosterone, insulin) were almost identically activated in both groups. However, Xe monoanesthesia provided an anabolic pattern and better preserved the defense mechanisms of the organism in comparison with N2O + phentanyl anesthesia. Moreover, the STH/hydrocortisone ratio was 2-fold higher in the Xe group vs. N2O + phentanyl group. The activities of thyroid hormones (TSH, T3, T4) fluctuated within the normal range, which was indicative of adequate phases of anesthesia in both groups. The parameters of central hemodynamics and metabolism also indicated sufficient depth of anesthesia.     

State of central hemodynamics in various kinds of anesthesia during short-term ENT surgery in children

The study was carried out in 124 children aged 4-10 years with ASA risk I or II. Group 1 consisted of 40 patients operated on under combined anesthesia with midazolam, fentanyl, and N2O, group 2 were 30 children operated on under mask anesthesia with fluothane, and nitric oxide + oxygen, group 3 patients were operated on under combined anesthesia with ketamine, midazolam, and N2O + CO2, and group 4 patients were operated on under thiopental and N2O + CO2. Cardiovascular function was evaluated by the NCCOM3-R-7 device (BoMed) by the bioimpedance method. Satisfactory cardiovascular function was observed in all groups, but the best stability was noted in the midazolam-fentanyl group. Hence, midazolam-fentanyl combination can be the method of choice in short-term ENT operations.     

Does the duration of N2O administration affect postoperative nausea and vomiting?

Nausea and vomiting are the most frequent postoperative complications in the ambulatory surgical setting. In the present study, data were obtained from 184 adult ambulatory cosmetic surgery patients to determine if the use of nitrous oxide (N2O) was associated with an increased incidence of postoperative nausea and/or vomiting (PNV). Anesthesia was induced with thiopental and maintained with an opioid (fentanyl or sufentanil) and isoflurane with or without N2O. Data were analyzed statistically using the two-way chi-square test and the Fisher Exact Test. The major finding was that the incidence of PNV was directly related to the duration of anesthesia in the patients who received N2O, but not in those who were N2O-free. Anesthesia times and the percentages of patients who exhibited PNV in the N2O-free and N2O-treated groups, respectively, were: (1) less than 1 hour, 0% and 6.3%; (2) between 1.0 and 1.9 hours, 35.3% and 36.8%; (3) between 2.0 and 2.9 hours, 24.2% and 66.7% (p = .06); (4) between 3.0 and 5.3 hours, 35% and 100% (P less than .05). Thus, avoidance of N2O in ambulatory cosmetic surgery cases lasting 3, and quite probably 2 or more hours in which general anesthesia is maintained with a synthetic opioid and isoflurane appears to reduce the likelihood that these short-stay patients will experience PNV.     

A comparative evaluation of "cerebral oximetry" during anesthesia with xenon and other anesthetics

The oxygen status dynamics during the general anesthesia is one of the most important issues of anesthetic monitoring. The set target was to study the cerebral oximetry (rSO2) in anesthesia with xenon as compared with other anesthetics. A total of 80 patients (class ASA I-II) were examined in the venectomy surgery. According to an anaesthetic used in induction and anesthesia management, the patients were divided into 3 groups. Group 1--40 patients with xenon mono-anesthesia; group 2--20 patients with propofol + N2O + neurolpangesia; and group 3--20 patients with N2O + ftorotan. At xenon induction, rSO2 went up by 6.4%. At propofol induction, there were no changes in rSO2. A biggest increase in the cerebral blood circulation was noted, at the anesthesia management stage, in the patients' group, who received ftorotan; a lesser increase was registered in xenon anesthesia. An increased rSO2 level was higher, during the wakening stage, in case of ftorotan administration than in the group, which received xenon; the process of recovering the initial parameters was slower in the former group. Xenon and ftorotan were shown to contribute to a higher oxygen status and an increased volume of the cerebral blood circulation. In case of xenon mono-anesthesia, there was a smaller increase in the cerebral blood circulation as compared to N2O + ftoratan anesthesia. Further special investigations are needed to give a final answer to the question on whether it is possible to use xenon in neuroanesthesiology and in intensive care of patients with a neuroresuscitation-type pathology of the brain.     

Relative reinforcing effects of three opioids with different durations of action

The role of duration of action on the relative reinforcing effects of three opioid drugs (fentanyl, alfentanil, and remifentanil) was evaluated. Duration and onset of action were determined using measures of respiratory depression and antinociception after i.v. administration. Effects on minute volume of respiration indicated that each of the three opioids had immediate onsets of action after i.v. administration. Fentanyl's duration of suppression of respiration and antinociception was longer than that of alfentanil, which was longer than that of remifentanil. Reinforcing strength was measured in i.v. self-administration studies in which the fixed ratio resulting in drug administration was increased from one session to the next. Comparisons were made of the behavioral economic variables P(max) and area under the demand curve (O(max)). Remifentanil maintained higher rates of responding than did alfentanil, and alfentanil maintained higher rates of responding than did fentanyl. When normalized demand functions were compared, however, the drugs did not differ significantly from each other in terms of P(max) or O(max). These data agree with those of others who have suggested that duration of action is not an important contributor to drugs' reinforcing strength.     

Inhalation anesthesia with halogen-containing anesthetics in children

The study was carried out in 158 children aged 3-16 years operated on in an inpatient setting. The patients were divided into 3 groups with different types of induction narcosis: 1) ethrane inhalation up to 3 vol% and N2O with O2 in 1:1 ratio (56 pts); 2) fluothane up to 3.5 vol% and N2O with O2 in 2:1 ratio (87 pts), and 3) isoflurane inhalation up to 3 vol% and N2O with O2 in 1:1 ratio (15 children). Central hemodynamics, cardiointervalograms, and external respiration function were studied. Ethrane and isoflurane induction was longer (4-12 min) than fluothane induction (3-5 min). Anesthesia with ethrane and isoflurane in combination with N2O with O2 led to a less pronounced reaction of the central hemodynamics than fluothane anesthesia, which led to a decrease of the sympathic tone and increase in the activity of the parasympathetic component of the autonomic nervous system. Analyzing a vast scope of clinical material on the use of inhalation anesthetics and all the pros and contras, the authors conclude that inhalation anesthetics can be used in children.     

A comparison of the effects of intrathecal fentanyl and lidocaine on established postamputation stump pain

Eight patients with established lower limb postamputation stump pain were given lumbar intrathecal fentanyl 25 micrograms and lidocaine 70 mg 2 weeks apart in an attempt to better understand the role of peripheral and central mechanisms in this condition. Baseline pain was recorded and then analgetic and side effects and their duration were assessed. Three self-administered questionnaires with appropriate psychometric proprieties were given to the patients. Intrathecal fentanyl always abolished the pain. Its onset was rapid being heralded within 1-2.5 min by a pleasant sensation of warmth involving the lower trunk and legs. Analgesia was complete by 5-10 min and had a median duration of 8 h. The patients had a sense of well being and were unable to elicit discomfort by pain aggravating maneuvers. Normal motor and sensory functions were retained. Pruritus was the only adverse effect unique to intrathecal fentanyl. Intrathecal lidocaine usually relieved the discomfort but was unable to abolish it in 3 of 8 patients despite adequate neural blockade. Its onset of action was slower and duration of effect shorter than fentanyl. Intrathecal fentanyl provided profound analgesia associated with normalization of stump sensations and euphoria, probably due to a segmental spinal action. The effects of lidocaine were inferior to fentanyl due to the associated motor and sensory paralyses as well as the absence of euphoria. This study suggests that, while peripheral mechanisms played a role, central mechanisms involving the spinal cord were more important in the modulation of established stump pain in the 8 subjects evaluated.     

The choice of a method of general anesthesia for patients with cancer of the abdominal cavity]

Two variants of anesthesiological management have been used in 135 patients with gastrointestinal tumors. The first variant was intubation anesthesia with N2O+O2, ketamine or sodium hydroxybutyrate combined with classical neuroleptanalgesia technique. Pentamine was used to potentiate protection. This anesthesia technique was used in patients under 50 who had no concomitant diseases. The second variant was used in patients over 50 with concomitant diseases. In these cases combined prolonged epidural anesthesia was accompanied in the intraoperative period with intubation anesthesia with controlled lung ventilation using N2O+O2 and additional administration of promedol and droperidol. The second variant of anesthesia not only ensured a safe intraoperative period but also optimized the management of patients in the postoperative period.     

Is the combination of nitrous oxide and hyperventilation in elective neurosurgical operations useful?

The use of nitrous oxide (N2O) and hyperventilation (HV) in elective neurosurgery is controversially discussed. The emphasis of the study was to show the effects of N2O and/or moderate hyperventilation (paCO2 31.0 +/- 1.2 mmHg) on parameters of cerebral metabolism: jugularvenous oxygen saturation (SjVO2), cerebral extraction of oxygen (CEO2), arterial jugularvenous difference of oxygen contents (AJDO2), arterial jugularvenous difference of lactate (AJDL) and glucose (AJDGL) and lactate-oxygen index (LOI). The study was approved by the Ethics Committee of the University of Leipzig. Forty patients undergoing an elective craniotomy for brain tumour resection were divided into four groups: group 1: n = 10, N2O + normoventilation (NV), group 2: n = 10, N2O + hyperventilation (HV), group 3: n = 10, O2/air + NV, group 4: n = 10, O2/air + HV. N2O + HV led to a significant decrease in SjVO2 from 68.1 +/- 10.7% to 49.7 +/- 5.6%. O2/Air + HV produced a drop from 67.1 +/- 11.1% to 49.8 +/- 7.7%. CEO2 increased significantly in the group N2O + HV from 30.6 +/- 10.6% to 49.6 +/- 5.5% and in the group O2/Air + HV from 31.7 +/- 11.1% to 50.0 +/- 7.8%. AJDO2 increased significantly in the group N2O + HV from 5.79 +/- 1.54 ml% to maximal 8.49 +/- 1.10 ml% and in the group O2/Air + HV from 5.29 +/- 1.76 ml% to maximal 8.03 +/- 1.76 ml%. In the normoventilation-groups 1 and 3, no significant changes in SjVO2, CEO2 and AJDO2 were observed between MP2 and 4. The parameters AJDL, AJDGL and LOI did not show any significant changes in any of the four groups. The described data represent a reduction of cerebral oxygenation, but deleterious effects caused by cerebral ischaemia could not be observed. Based on our data, hyperventilation and its combination with N2O should not be used routinely in neuroanaesthesia.     

Effects of multiple daily injection therapy with Humalog mixtures versus separately injected insulin lispro and NPH insulin in adults with type I diabetes mellitus

BACKGROUND: Injection of insulin lispro (LP) before meals provides a more physiologic insulin activity profile than regular human insulin, but the relatively short duration of action of LP may allow the blood glucose (BG) level to increase during the late postprandial period (4-7 hours after meals) unless basal insulin is optimally replaced. One approach to basal insulin optimization has been to combine small doses of NPH with LP before meals. When used in a similar fashion, premixed, fixed-ratio insulin preparations containing LP and NPL (an LP-based intermediate-acting insulin) may provide the basis for an optimized basal-bolus insulin regimen. OBJECTIVE: This study assessed mean late postprandial glycemic control during treatment with a premixed formulation consisting of a high proportion of LP (75% LP/25% NPL; H) and a premixed formulation consisting of a medium proportion of LP (50% LP/50% NPL; M). The H/M formulation was given before meals and was compared with treatment with preprandial LP + NPH (LP + N) in patients with type 1 diabetes mellitus (DM). METHODS: This multicenter, randomized, open-label, 2-period crossover study was conducted at 4 centers in Italy and 1 center in France. Patients eligible for the study had type 1 DM, were > or = 18 years of age, and had a glycosylated hemoglobin (HbA(1c)) <150% of the upper limit of normal. Patients were randomly assigned to 1 of 2 treatment sequences: LP self-mixed with NPH before meals plus NPH alone at bedtime for 8 weeks (LP + N) followed by preprandial H or M, plus NPH alone at bedtime for 8 weeks (H/M), or the opposite sequence. Assessments included 8-point self-monitored BG profiles, HbA(1c), and hypoglycemia (any sign or symptom of hypoglycemia or BG < 3.0 mmol/L [<54.0 mg/dL]). The primary outcome measure was the late postprandial BG value, calculated as the mean of the combined prelunch (late postbreakfast), predinner (late postlunch), and bedtime (late postdinner) values. RESULTS: A total of 89 patients with type 1 DM were enrolled (44 men, 45 women; mean [SD] age, 38.3 [12.8] years; mean [SD] body weight, 70.8 [11.6] kg; mean [SD] body mass index, 24.6 [3.0] kg/m(2); mean [SD] duration of diabetes, 17.8 [10.5] years; mean HbA(1c), 7.9% [0.88%]). The mean (SD) late postprandial BG values were similar between treatments (8.9 [2.1] mmol/L [160.3 (37.8) mg/dL] for H/M vs 9.0 [1.8] mmol/L [162.1 (32.4) mg/dL] for LP + N), as were the end point HbA(1c) values (7.8% [0.9%] for H/M vs 7.9% [0.8%] for LP + N). The rate of hypoglycemia was significantly higher during treatment with H/M, primarily because of episodes occurring between 12 PM and 6 PM, but was relatively low in both groups (mean/median rate per patient per 30 days: 2.87/2.14 for H/M and 2.11/1.07 for LP + N; P < 0.05). CONCLUSIONS: In this population of patients with type 1 DM, preprandial H/M provided an effective alternative regimen for prandial and basal insulin replacement. Late postprandial BG control, an indicator of basal insulin sufficiency, was similar to that achieved with an intensified regimen of LP + N injected separately before meals, and the end point HbA(1c) was similar between the 2 treatments.     

Patterns of dosage changes with transdermal buprenorphine and transdermal fentanyl for the treatment of noncancer and cancer pain: a retrospective data analysis in Germany

BACKGROUND: Previous studies have suggested that buprenorphine may have a low association with tolerance development compared with other strong opioids. In a previous study by our group, mean cohort and intraindividual dosage increases over an entire course of treatment and on a per-day basis were significantly lower with transdermal (TD) buprenorphine than with TD fentanyl. However, no information concerning the relationship between qualitative and quantitative dose changes is available. OBJECTIVE: The aim of this study was to compare TD buprenorphine and TD fentanyl with respect to dosage increases, dosage stability, and the nature of dosage changes. METHODS: This retrospective analysis used data from the IMS Disease Analyzer-Mediplus database, which contains patient-related data documented by 400 medical practices in Germany. Data from patients with noncancer or cancer pain treated with TD buprenorphine or TD fentanyl for at least 3 months between May 2002 and April 2005 were analyzed. Daily dosages were directly determined from the prescribed patch strength, taking into account the possibility of multiple patches applied simultaneously. To determine dosage stability, patients were classified based on the type of dosage change (stable, increase, alternating, or decrease) of the prescribed dosages. From the prescribed daily dosages, mean percentage increases were calculated on a per-patient basis for the entire treatment period and per day, and these were assessed in relation to the type of dosage change. RESULTS: In total, 631 patients with noncancer pain and 605 patients with cancer pain were included in the analysis (782 women, 454 men; mean age, 76.3 years [range, 29-100 years]). Treatment indications included osteoarthritis, low back pain, osteoporosis (noncancer groups), and neoplasm (cancer groups). Patients had similar analgesic premedication requirements based on steps 1 to 3 of the World Health Organization analgesic ladder. Comedication requirements for breakthrough pain were also similar between the TD buprenorphine and TD fentanyl groups. The mean percentage increases per day were 0.10% (TD buprenorphine) and 0.25% (TD fentanyl) in the noncancer groups and 0.19% (TD buprenorphine) and 0.47% (TD fentanyl) in the cancer groups (both, P < 0.05). A significantly larger proportion of patients receiving TD buprenorphine had stable dosages over the entire treatment period compared with patients receiving TD fentanyl (noncancer groups: 56.9% vs 41.6%; cancer groups: 50.0% vs 26.2% [both, P < 0.05]). Compared with TD buprenorphine, the proportion of patients with alternating dosage changes was significantly greater in patients receiving TD fentanyl (noncancer groups: 22.7% vs 13.1%; cancer groups: 30.6% vs 11.8% [both, P < 0.05]). CONCLUSIONS: In this retrospective data analysis, compared with TD buprenorphine, the increase in mean daily dosage was significantly greater in patients treated with TD fentanyl. Also, compared with TD buprenorphine, alternating dosage changes were seen in a significantly greater proportion of patients receiving TD fentanyl. On the other hand, a significantly greater proportion of patients treated with TD buprenorphine had stable dosages over their entire treatment periods.     

Controlled combination anesthesia

The improvement of combined anesthesia is associated with the improvement of its control. The latter is possible only with continuous administration of anesthetics. 130 procedures of combined anesthesia were performed in patients subject to abdominal and other types of operations. With this in view fentanyl and calipsol were continuously injected, using modified dosators, to patients pretreated with N2O and total curarization. It has been found that with continuous administration adequate analgesia with stable blood pressure can be achieved provided that 1/3-2/3 of the total fentanyl dose is used as a loading dose at the beginning of anesthesia. The maintenance dose does not change considerably blood anesthetic concentration. If required, changes in the concentrations were achieved by additional fentanyl administration, using a dosator for 25-50 mukg. The technique described has advantages over bolus drug injection and continuous drug infusion. The technique may be considered a controlled one.     

Investigation of the teratogenic and embryotoxic action of xenon

30 Wistar rats inhaled a Xe (80%):O2(20%) mixture for 2 hours twice a week on the 1st to 19th days of pregnancy. On the 20th day of pregnancy 70% rats were exposed to euthanasia, the rest of animals were left for labors to study the postnatal course in the progeny. Inhaling the Xe (80%):O2(20%) mixture did not affect either the changes in body mass of pregnant rats, indices of postimplantating loss of embryos and pregnancy duration or the number of live newborns, their body mass and sizes. Xenon caused neither inhibition of osteal system development nor any malformations. The results of study permit one to look optimistically at the prospects for using Xenon in obstetrical anesthesiology.     

Brief wakeful response to command indicates wakefulness with suppression of memory formation during surgical anesthesia

Objective. In a previous study of patients emerging from anesthesia following surgery, we found that a brief wakeful response to command of an eye opening or single hand squeeze or count was not associated with memory formation, while the response of four hand squeezes or counts was associated with memory. We wanted to determine the anesthetic requirements for obtaining this brief wakeful response endpoint during surgery and to determine if memory occurred at this endpoint during surgical anesthesia.Methods. Six different combinations of isoflurane, 70% N₂O, and fentanyl were administered to 326 patients undergoing pelvic laparoscopy. After insertion of the trocar, anesthesia was reduced while patients were given verbal commands, and they were observed for movement responses to surgery and to command. Patients were classified as either not arousing, arousing with a movement response to surgery, or arousing with a wakeful response to command. For the patients who aroused, we calculated the percentage of arousal responses that were wakeful responses to command. The effect of fentanyl dosage upon the percentage of arousal responses that were wakeful responses to command was determined by using a Mann-Whitney test to compare a group of patients receiving fentanyl 2 µg/kg or less, with a group receiving fentanyl 4 µg/kg. In a subset of 39 patients, the potential for memory formation was evaluated by presenting a target sound to 29 patients during a period of either no arousal, movement response to surgery, or wakeful response to command; for a control group of 10 patients, no target sound was presented. All 39 patients were tested for memory of the target sound; the results from each group receiving a target sound were compared with the results of the control group, using a Mann-Whitney test.Main Results. A total of 68 patients aroused with either a movement response or a wakeful response to command. Wakeful responses occurred with only 1 of 39 patients (3%) receiving fentanyl 2 µg/kg or less; but, wakeful responses occurred with 17 of 29 patients (59%) receiving fentanyl 4 µg/kg. The difference between the groups was significant atp=0.01. None of the 68 patients had recall of intraoperative events or unpleasant dreams. None of these patients who were in the multiple-choice memory subset recalled the target sound. There were no statistically significant differences on the multiple-choice memory test between the groups presented with the target sound and the control group. Patient anecdotes suggested that some patients may have had memory of the target sound; but, memory was no more likely in patients with a brief wakeful response to command than in those who responded with a movement to surgical stimulation or those who did not have an arousal response.Conclusions. A brief wakeful response to a command of opening the eyes or squeezing the hand was not associated with increased memory formation during surgery. A brief wakeful response to command was found during surgery when patients received fentanyl 4 µg/kg; but it was rarely found at fentanyl dosages of 2 µg/kg or less.     

小剂量氯胺酮静脉自控镇痛对严重烧伤休克期患者细胞因子平衡的影响

目的 探讨严重烧伤休克期患者静脉注射小剂量氯胺酮或联合芬太尼静脉自控镇痛（PCIA）对细胞因子平衡的影响。方法 45例严重烧伤患者于伤后24h内入院，随机分为传统镇痛（CAT）、静脉注射氯胺酮自控镇痛（PCIKA）和静脉注射芬太尼加氯胺酮自控镇痛（PCIKFA）3组，每组15例。在积极抗休克的同时，CAT组患者根据需要肌肉注射哌替啶50mg和异丙嗪25mg，PCIKA组给予氯胺酮20g／L＋氟哌利多50mg／L，PCIKFA组给予氯胺酮10g／L＋芬太尼5mg／L＋氟哌利多50mg／L，PCIA负荷量均为1ml，PCIA用量为1ml，锁定时间30min，持续输入量1．5ml／h。检测镇痛前和镇痛后1、8、24和48h血清中白细胞介素-1（IL-1）、IL-6、肿瘤坏北因子-α（TNF-α）的浓度。结果 PCIKA、PCIKFA两组患者镇痛效果明显优于CAT组（P均〈0．01）。镇痛评分较镇痛前及CAT组明显降低（P均〈0．01）各组患者无恶心、呕吐、幻觉及呼吸抑制等不良反应。两组PCIA患者镇痛开始后IL-1、TNF-α与镇痛前比较无明显变化（P均〉0．05），而TL-6镇痛开始后24h与镇痛前比较明显降低（P〈0．01），两组PCIA患者IL-1、IL-6及TNF-α均明显低于CAT组（P均〈0．01）。结论 严重烧伤休克期患者静脉注射小剂量氯胺酮或联合芬太尼进行自控镇痛安全、有效，并有助于维持此类患者休克期细胞因子的平衡状态。     

笑气吸入在人工流产镇痛中的应用及护理

[目的 ]探讨笑气吸入在早孕人工流产术中的镇痛作用。 [方法 ]随机将 2 91例人工流产病例分为两组。观察组 191例 ,以笑气吸入后行人工流产术。对照组 10 0例 ,2 %利多卡因宫颈处封闭后行人工流产术。 [结果 ]观察组笑气吸入后 ,镇痛效果良好 ,与对照组比较 ,有统计学意义 (P <0 .0 1)。 [结论 ]笑气吸入在早孕人工流产术中有良好的镇痛效果 ,结合有效的心理护理 ,使孕妇易于接受并配合手术 ,减轻了病人的痛苦     

复合小剂量芬太尼在氯胺酮-丙泊酚小儿静脉全身麻醉中的效果

目的观察小剂量芬太尼在氯胺酮-丙泊酚小儿静脉全身麻醉的效果,为临床麻醉方案的选择提供参考。方法选取接受手术治疗的患儿78例,随机分为观察组和对照组各39例。对照组采用氯胺酮-丙泊酚复合麻醉,观察组采用小剂量芬太尼复合氯胺酮-丙泊酚麻醉。对比两组患儿麻醉过程中的心率(HR)、呼吸次数(RR)、血氧饱和度(Sp O2)和术后苏醒的情况,同时采用11点数字评分法评估患儿术后24 h的疼痛情况。结果麻醉后5 min、麻醉后10 min,两组患儿的RR、HR均显著高于麻醉前(均P0.05),而麻醉前后Sp O2的对比,差异均无统计学意义(P0.05);观察组术后完全清醒、能遵医嘱咳嗽、肢体可有意识活动的患者比率均显著高于对照组(P0.05);观察组术后1 h无痛的比率为56.41%,术后6 h无痛的比率为46.15%,术后24 h无痛的比率为38.46%,均显著高于对照组(P均0.05)。结论小剂量芬太尼复合氯胺酮、丙泊酚具有良好的麻醉、镇痛效果,对患儿的循环系统影响小,术后苏醒时间短,镇痛效果好,不良反应少,是小儿静脉全身麻醉较为理想的麻醉方法。     

Comparison between intravenous morphine versus fentanyl in acute pain relief in drug abusers with acute limb traumatic injury

BACKGROUND: Rapid and effective pain relief in acute traumatic limb injuries (ATLI) is one of the most important roles of emergency physicians. In these situations, opioid addiction is an important concern because of the dependency on opioids. The study aims to compare the effectiveness of intravenous (IV) fentanyl versus morphine in reducing pain in patients with opioid addiction who suffered from ATLI. METHODS: In this double-blind randomized clinical trial, 307 patients with ATLI, who presented to the emergency department (ED) from February 2016 to April 2016, were randomly divided into two groups. One group (152 patients) received 0.1 mg/kg IV morphine. The other group (155 patients) received 1 mcg/kg IV fentanyl. Patients’ demographic data, pain score at specific intervals, vital signs, side effects, satisfaction and the need for rescue analgesia were recorded. RESULTS: Eight patients in the morphine group and five patients in the fentanyl group were excluded. Pain score in the fentanyl group had a significant decrease at 5-minute follow-up (P value=0.00). However, at 10, 30, and 60-minute follow-ups no significant differences were observed between the two groups in terms of pain score reduction. The rescue analgesia was required in 12 (7.7%) patients in the fentanyl group and in 48 (31.6%) patients in the morphine group (P value=0.00). No significant difference was observed regarding side effects, vital signs and patients’ satisfaction between the two groups. CONCLUSION: Fentanyl might be an effective and safe drug in opioid addicts suffering from ATLI.