Effect of gabapentin pretreatment on propofol consumption,hemodynamic variables,and postoperative pain relief in breast cancer surgery

Study objectiveGabapentin is an inhibitory neurotransmitter of the central nervous system. This prospective randomized double-blind study was conducted to evaluate the effects of gabapentin on intraoperative propofol requirements, hemodynamic variables, and postoperative pain relief in breast cancer patients.Materials and methodsForty adult females of the American Society of Anesthesiologists (ASA) Grade I-II physical status, undergoing total mastectomy for breast cancer were included. Patients were randomly allocated into two groups. Two hours prior to surgery the gabapentin group received gabapentin 600 mg and the control group received placebo. Anesthesia was induced with intravenous fentanyl, propofol, and vecuronium, and maintained with propofol infusion titrated according to the bispectral index. Postoperative analgesia was provided with intramuscular diclofenac sodium and intravenous morphine on demand.ResultsThe intraoperative propofol consumption was significantly less in the gabapentin group as compared with the control group (p = 0.009), whereas there was no difference in fentanyl and vecuronium requirements. Patients in the gabapentin group had lower pain scores at 30 minutes, 1 hour, and 2 hours postoperatively (p < 0.001). The postoperative morphine consumption was also less in the gabapentin group compared with the control group (p = 0.006). No significant adverse effects were noticeable.ConclusionPreoperative administration of gabapentin reduced intraoperative propofol requirements and postoperative analgesic consumption in breast cancer patients undergoing total mastectomy.     

Continuous epidural infusion for postoperative pain relief: A comparison of three regimens

We evaluated the postoperative pain relief and side-effects of continuous epidural infusion of three analgesic regimens following major thoracic and/or abdominal surgery. One hundred and twenty patients were randomly divided into three treatment groups: (1) 0.25% or 0.5% bupivacaine at a rate of 3–7ml·hr^–1, (2) 0.01% morphine at a rate of 1–2ml·hr^–1, (3) a combination of 0.125% or 0.25% bupivacaine and 0.0025% or 0.005% morphine at a rate of 2–4ml·hr^–1. The study continued for the first 48 postoperative hours. The effect of pain relief was evaluated by assessment of the further requirement for parenteral analgesics. Sixty-four percent of the patients given bupivacaine, 56% of the patients given morphine and 80% of the patients given the combination required no supplemental analgesics. Continuous epidural infusion of bupivacaine was associated with hypotension (21%) and with numbness and weakness of hands or legs (18%). Continuous epidural infusion of morphine was associated with pruritus (18%) and with peristaltic depression (12%). The combination regimen was associated with pruritus (17%) and with drowsiness (14%). We conclude that the combination of bupivacaine and morphine significantly provides superior analgesia with less deleterious complications compared with either bupivacaine or morphine alone.(Sakura S, Uchida H, Saito Y et al.: Continuous epidural Infusion for postoperative pain relief: A comparison of three regimens. J Anesth 4: 138–144, 1990)     

咪唑安定对丙泊酚诱导需要量的影响

目的　评估咪唑安定预先给药对减少丙泊酚需要量的影响。方法　ASAⅠ～Ⅱ择期手术病人 1 2 0例 ,随机分为丙泊酚组 (A组 )、咪唑安定 0 0 4mg/kg +丙泊酚组 (B组 )和咪唑安定 0 0 6mg/kg +丙泊酚组 (C组 ) ,按丙泊酚剂量每组又分为 4个亚组 :A组分为 0 75、1 1 3、1 6 8和 2 5mg/kg 4个亚组 ;B和C组均分为 0 33、0 5、0 75和 1 1 3mg/kg 4个亚组。A组直接静注丙泊酚 ,B和C组分别静注咪唑安定 0 0 4mg/kg或 0 0 6mg/kg ,6min后静注丙泊酚 ,速度均为1 5mg/s。静注丙泊酚或咪唑安定后 6min内每分钟进行OAA/S评分 ,并记录BIS。结果　 (1 )OAA/S与BIS具有显著等级相关 (r =0 81 9,P <0 0 1 )。三次模型拟合曲线可表示OAA/S与BIS之间的关系 (r =0 6 83,P<0 0 1 )。 (2 )以OAA/S =0分为判断丙泊酚效应指标 ,A组丙泊酚的ED50 和ED95分别为 1 0 9mg/kg和 1 6 4mg/kg ;B组和C组分别使丙泊酚的ED50 下降 5 2 3%和 6 0 5 % ,ED95下降 4 7 6 %和5 1 8%。 (3)静注丙泊酚后 1～ 2min ,BIS下降到最低值。与A组相比 ,B和C组使BIS降至相应值的丙泊酚需要量明显减少 ,同时BIS维持低水平的时间显著延长。结论　预先静注咪唑安定 0 0 4mg/kg可显著减少丙泊酚用量 ,并延长其作用时间     

Effects of magnesium sulphate and clonidine on propofol consumption, haemodynamics and postoperative recovery

Background. This placebo-controlled, double-blind study wasdesigned to assess the effects of magnesium sulphate and clonidineon peroperative haemodynamics, propofol consumption and postoperativerecovery. Methods. Sixty ASA I–II patients undergoing spinal surgerywere randomized into three groups. Group M received magnesiumsulphate 30 mg kg^–1 as a bolus before induction and 10mg kg^–1 h^–1 by infusion. Group CL received clonidine3 µg kg^–1 as a bolus before induction and 2 µgkg^–1 h^–1 by infusion during the operation period.The same volume of isotonic solution was administered to thecontrol group (group CT). Anaesthesia was induced with propofoland was maintained with propofol infusion [dose according tothe bispectral index (BIS)], fentanyl and cisatracurium. Analysisof variance and the Bonferroni test were used for statisticalanalysis. Results. Induction of anaesthesia with propofol was rapid inthe presence of magnesium sulphate and clonidine. The time forBIS to reach 60 was significantly shorter in group M and groupCL (P<0.0001) but postoperative recovery was slower withmagnesium sulphate compared with the clonidine and control groups(P<0.0001). There was no statistical difference in heartrate and arterial blood pressure between the groups. Propofolrequirements for induction and maintenance of anaesthesia weresignificantly lower with magnesium and clonidine (P<0.0001). Conclusion. Clonidine caused bradycardia and hypotension andmagnesium sulphate caused delayed recovery, but can be usedas adjuvant agents with careful management.     

Low dose intrathecal morphine and postoperative pain relief in elderly patients]

Patient (ASA PS I-III, mean age 68 +/- 14 yr) who had undergone lower extremity surgery under spinal anesthesia were studied to determine the effect of intrathecal administration of morphine 0.1 mg on intra- and postoperative pain relief and its side effects. They were randomly divided into control (C) and intrathecal morphine (M) groups (n = 25, respectively) and received 10 mg tetracaine in 4 ml of a quarter saline with 7.5 micrograms epinephrine. Incidence of intraoperative tourniquet pain was significantly lower in M group (36.8%) than in C group (64.3%). Postoperative pain was examined in terms of the duration until the first supplemental analgesic within 24 hr. The mean duration was 7.0 +/- 4.3 hr in the control group, but 11 patients in the M group needed it within 24 hr (18.1 +/- 6.8 hr, excluding 6 patients who did not receive analgesic). Although incidences of postoperative nausea, vomiting, and itching were higher in M group than in C group, none required antiemetic or naloxone. Both groups showed no difference in postoperative respiratory depression measured by apnea monitor (Eden Trace II, Mallinkrodt Japan, Tokyo). The results suggest that a low dose of intrathecal morphine is effective on postoperative 24 hr pain relief in elderly patients and that its side effects are negligible.     

Caudal anaesthesia for postoperative pain relief in children: a comparative trial of different regimens using plain bupivacaine.

A comparative trial between three different dosage regimens of bupivacaine administered by the caudal route, used for the prevention of postoperative pain in children undergoing elective inguinal herniotomy or ligation of patient processus vaginalis was undertaken. The regimens compared were bupivacaine 0.25% (1 ml/kg), bupivacaine 0.25% or 0.5%: (Age (years +2)/10 ml per dermatome to be blocked. This being calculated for inguinal surgery to be Age (years) + 2 ml. A linear analogue pain scale was used to evaluate pain, all three regimens being found to produce excellent analgesia, there being no significant difference between the pain scores of the three groups. Time to onset of analgesia, as indicated by changes in intraoperative heart rate in response to surgical stimulation were also similar in all groups. No evidence of postoperative motor weakness or disturbance of bladder function was found and there were no symptoms or signs attributable to local anaesthetic toxicity.     

Effects of a single pre-operative dexmedetomidine dose on isoflurane requirements and peri-operative haemodynamic stability

In a double-blind, placebo-controlled study we investigated the effect of a single pre-induction intravenous dose of dexmedetomidine 2 μg.kg⁻¹ on anaesthetic requirements and peri-operative haemodynamic stability in 50 patients undergoing minor orthopaedic and general surgery. Patients were anaesthetised with nitrous oxide/oxygen/fentanyl, supplemented if necessary with isoflurane. The mean (SD) intra-operative isoflurane concentration was lower in the dexmedetomidine-treated patients than controls (0.01 (0.03)% compared to 0.1 (0.1)%; p = 0.001) although six of the 25 treated patients required isoflurane at some stage. The haemodynamic response to tracheal intubation and extubation was reduced in the dexmedetomidine group as was intra-operative heart rate variability; postoperative analgesic and anti-emetic requirements and peri-operative serum catecholamine concentrations were lower in the dexmedetomidine group. Hypotension and bradycardia occurred more frequently after dexmedetomidine.     

不同剂量丙泊酚持续静注对心内直视手术病人肌钙蛋白I的影响

目的观察不同剂量丙泊酚对心内直视术病人肌钙蛋白-Ⅰ(CTn-Ⅰ)的影响,寻求丙泊酚抑制心肌缺血再灌注损伤作用合适的剂量.方法27例心内直视手术患者随机分成A、B、C三组.咪唑安定、丙泊酚、维库溴铵、芬太尼诱导后,用微量泵持续输注丙泊酚,A组2mg@kg-1@h-1、B组5mg@kg@h-1、C组8mg@kg-1@h-1.用化学发光法测定诱导后、停心肺转流(CPB)即刻、CPB后30、60分钟和CPB后3小时动脉血CTn-Ⅰ浓度.结果三组病人CPB后CTn-Ⅰ均显著升高(P＜0.01).组间比较,B组CPB后CTn-Ⅰ值比A组低(P＜0.05和P＜0.01).C组和A组间CTn-Ⅰ值无统计学差异.结论心脏手术术中及术后CTn-Ⅰ升高提示心肌存在不同程度损伤.术中5mg@kg@h-1丙泊酚持续静注是较为理想的具有心肌保护作用的临床用药剂量.     

Effect of omitting regular ACE inhibitor medication before cardiac surgery on haemodynamic variables and vasoactive drug requirements

Adverse events during coronary artery bypass graft (CABG) surgery have been described in patients receiving angiotensin converting enzyme (ACE) inhibitors, including hypotension on induction of anaesthesia and an increase in vasoconstrictor requirements after cardiopulmonary bypass (CPB). Omitting regular ACE inhibitor medication before surgery may improve cardiovascular stability during anaesthesia. We evaluated prospectively the effect of omitting regular ACE inhibitor medication before CABG surgery on haemodynamic variables and use of vasoactive drugs. We studied 40 patients with good left ventricular function, allocated randomly to omit or continue ACE inhibitor medication before surgery. Arterial pressure, cardiac output, systemic vascular resistance and use of vasoactive drugs were recorded during anaesthesia and in the early postoperative period. Patients who omitted their ACE inhibitors had greater mean arterial pressure during the study and required less vasopressors during CPB. However, these patients required more vasodilators to control hypertension after CPB and in the early postoperative period. There was no difference in hypotension on induction of anaesthesia or in the use of vasoconstrictors after CPB. We conclude that omitting ACE inhibitors before surgery did not have sufficient advantage to be recommended routinely.      

The effect of dextromethorphan, alone or in combination with ibuprofen, on postoperative pain after minor gynaecological surgery

BACKGROUND: Experimental studies have demonstrated that peripheral tissue injury may lead to hyperexcitability of nociceptive neurones in the dorsal horn, in part mediated by N-methyl-D-aspartate (NMDA)-receptor mechanisms. Sensitisation of dorsal horn neurones may be an important contributor to postoperative pain. The aim of the present study was to investigate the effect of the NMDA-receptor antagonist dextromethorphan on pain after minor gynaecological surgery, and to evaluate a potential additive effect with ibuprofen. METHODS: In a double-blind, placebo-controlled study, 100 patients scheduled for elective termination of pregnancy were randomised to receive placebo, oral ibuprofen 400 mg, oral dextromethorphan 120 mg, or a combination of ibuprofen 400 mg and dextromethorphan 120 mg, 1 h before surgery. Pain and analgesic requirements were assessed 0.5, 1 and 2 h after operation. RESULTS: We observed no effect of dextromethorphan on visual analogue scale (VAS) pain scores or analgesic consumption, and no additive or synergistic analgesic effects between ibuprofen and dextromethorphan. Ibuprofen reduced pain scores compared with placebo, and analgesic consumption compared with both placebo and dextromethorphan. The combination of ibuprofen and dextromethorphan increased preoperative nausea compared with both placebo and ibuprofen, whereas no statistically significant side effects were observed with dextromethorphan alone. CONCLUSION: No analgesic effects of oral dextromethorphan 120 mg on pain after surgical termination of labour, and no additive analgesic effects when combined with ibuprofen 400 mg, were observed. Ibuprofen reduced both VAS pain scores and analgesic consumption compared with placebo.     

Influence of dose and timing of administration of morphine on postoperative pain and analgesic requirements

In a randomized, double-blind study, we have investigated the effect of dose and timing of administration of morphine on postoperative pain and analgesic requirements in 60 patients undergoing hysterectomy, with or without salpingo-oophorectomy. Patients were allocated randomly to one of three groups: during standardized general anaesthesia, group post received morphine 0.15 mg kg-1 i.v. at peritoneal closure after hysterectomy; group pre-low received morphine 0.15 mg kg-1 on induction of anaesthesia; and group pre-high received morphine 0.3 mg kg-1 on induction of anaesthesia. Median postoperative morphine consumption (first 24 h) from a PCA system was 68 mg (group post), 56 mg (group pre- low) and 43 mg (group pre-high), and total perioperative morphine consumption (induction of anaesthesia to end of 24 h after surgery) was 77 mg (group post), 65 mg (group pre-low) and 63 mg (group pre-high). Pain scores (at rest and on movement) were similar in the three groups. A large dose of morphine 0.3 mg kg-1 i.v. on induction of anaesthesia significantly reduced postoperative PCA morphine requirements compared with the smaller dose (0.15 mg kg-1) administered at induction or peritoneal closure, in patients undergoing hysterectomy, with or without salpingo-oophorectomy.      

Effects of lidocaine aerosol on postoperative pain and wound tenderness following minor gynaecological laparotomy

Twenty-four female patients undergoing sterilization through a minor lower laparotomy received, in a double-blind, randomized study, either lidocaine spray 200 mg or placebo in the surgical wound. Postoperative pain intensity was evaluated on a verbal and a visual analogue scale and wound tenderness with an algometer. During mobilisation from the supine to the sitting position, VAS-score was lower (P less than 0.05) in the lidocaine group 2 h postoperatively, but not 4, 6 and 8 h postoperatively (P greater than 0.05). No significant differences were found in VAS-scores at rest or during cough, or in verbal scale ratings during rest, cough or mobilisation, and postoperative consumption of morphine was similar in the two groups. Pressure pain thresholds were higher (P less than 0.05) 2 h postoperatively in the lidocaine group, but not 4, 6 and 8 h postoperatively. In conclusion, topically applied lidocaine aerosol in the surgical wound leads to very short and clinically insignificant relief of postoperative pain.     

Effects of premedication on dose requirements for propofol: comparison of clonidine and hydroxyzine

The influence of a single dose of clonidine (5 micrograms kg-1) or hydroxyzine (1 mg kg-1) on intraoperative propofol requirements was determined in 28 male patients (ASA I) undergoing elective orthopaedic surgery. Patients were randomly allocated to receive either clonidine or hydroxyzine orally 2 h before induction of anaesthesia. After a loading dose of propofol (2.5 mg kg-1), mivacurium (0.2 mg kg-1) and alfentanil (15 micrograms kg-1), anaesthesia was maintained with a standardized propofol infusion supplemented with nitrous oxide (66%) in oxygen. During surgery, additional propofol boluses (1 mg kg-1) were administered when heart rate or mean arterial pressure increased by more than 10% compared with preinduction values. The clonidine group demonstrated a 14.5% decrease in total propofol requirements (P < 0.05) and a 52.2% reduction in additional propofol boluses (P < 0.02) in comparison with the hydroxyzine group. intraoperative heart rate and mean arterial pressure were significantly lower in the clonidine group but no patients needed treatment with ephedrine for hypotension or bradycardia. Recovery of psychomotor function and discharge from the recovery room were not delayed in the clonidine group. This study indicates that 5 micrograms kg-1 clonidine given as premedication in ASA I patients reduces intraoperative propofol requirements in comparison with 1 mg kg-1 hydroxyzine without inducing adverse effects on recovery or haemodynamic stability.      

不同剂量羟考酮对腹部手术后急性疼痛的抑制作用

目的探讨不同剂量羟考酮对腹部手术后急性疼痛的抑制作用。方法择期全麻下行腹部手术患者60例,ASAⅠ或Ⅱ级,年龄30~70岁,随机均分为四组:羟考酮0.05mg/kg组(OL组)、羟考酮0.1mg/kg组(OM组)、羟考酮0.2mg/kg组(OH组)和对照组(C组)。两组麻醉诱导采用静脉注射咪达唑仑0.03mg/kg、丙泊酚2.0~2.5μg/kg、顺阿曲库铵0.2mg/kg、舒芬太尼0.6μg/kg;麻醉维持采用瑞芬太尼5~10μg·kg-1·h-1、丙泊酚4~6mg·kg-1·h-1、顺阿曲库铵0.1mg·kg-1·h-1。关腹时羟考酮组给予相应剂量的羟考酮抑制术后疼痛。于患者清醒后行NRS评分(对所有NRS大于4分者给予羟考酮镇痛),记录患者苏醒时间、清醒后的疼痛数字评分、镇痛持续时间、以及恶心、呕吐、瘙痒等不良反应的发生情况。结果与C组比较,OH组患者苏醒时间明显延长,OL、OM和OH组患者的NRS评分均明显降低,镇痛持续时间明显延长(P<0.05或P<0.01);与OL组比较,OM和OH组NRS评分明显降低,镇痛持续时间明显延长(P<0.05)。结论在关腹前给予羟考酮具有抑制腹部手术后疼痛的作用,但0.1mg/kg的羟考酮最适宜,既能达到良好的镇痛效果,同时又不影响患者的苏醒。     

七氟醚或丙泊酚维持麻醉对妇科腹腔镜手术患者术后疼痛的影响

目的通过观察不同麻醉维持方式下妇科腹腔镜手术患者术后疼痛的情况,比较七氟醚或丙泊酚维持麻醉对患者术后疼痛的影响。方法选择择期行妇科腹腔镜手术女性患者60例,年龄18~65岁,BMI 18~30 kg/m^2,ASAⅠ或Ⅱ级。采用随机数字表法随机分为七氟醚组(S组)和丙泊酚组(P组),每组30例。两组以相同方案麻醉诱导后,S组吸入1.5%~4%七氟醚维持麻醉,P组靶控输注丙泊酚,血浆靶浓度3~6μg/ml。术中维持BIS 40~60。记录术后30 min、1、3、6、24和48 h时患者活动时VAS评分;记录术前1 d、术后3、24和48 h机械性痛阈值;记录术后24 h PCIA按压次数、芬太尼消耗量;记录追加哌替啶的例数和恶心呕吐、寒颤、瘙痒、躁动等不良反应发生情况。结果与术后30 min比较,术后3、6 h两组活动时VAS评分明显升高(P<0.05),术后48 h明显降低(P<0.05)。术后30 min、1和3 h P组活动时VAS评分明显低于S组(P<0.05)。与术前1 d比较,术后3、24和48 h S组机械性痛阈明显降低(P<0.05),术后3 h P组机械性痛阈明显降低(P<0.05)。术后3 h P组机械性痛阈值明显高于S组(P<0.05)。两组PCIA按压次数、芬太尼消耗量、追加哌替啶情况和不良反应发生情况等差异无统计学意义。结论与七氟醚吸入维持麻醉比较,妇科腹腔镜手术中使用丙泊酚静脉维持麻醉可以提高患者术后的机械性痛阈,减轻患者在术后3 h内的疼痛。     

A comparison of nalbuphine and pethidine for postoperative pain relief after orthopaedic surgery

Nalbuphine hydrochloride (Nubain; Du Pont Pharmaceuticals), a synthetic agonist-antagonist analgesic, in a dose of 20 mg was compared with pethidine 100 mg in 60 patients after elective surgery in a random double-blind study. Both drugs were given intramuscularly on the first day after surgery. The pain intensity and visual analogue scales would seem to indicate that nalbuphine has a longer duration of action than pethidine (P less than 0,05). The respiration rates in the pethidine group were significantly more depressed 30 minutes after the injection than in the nalbuphine group (P less than 0,05). Nalbuphine caused less depression of both systolic and diastolic blood pressure at both 30 and 60 minutes (P less than 0,001). The results of the study show that nalbuphine, in the dose used here, may prove to be a useful substitute for pethidine.     

Comparison of parenteral diclofenac and ketoprofen for postoperative pain relief after maxillofacial surgery

Non-steroidal anti-inflammatory drugs (NSAID) effectively reduce the need for opioid analgesia after various types of surgery. The efficacy of diclofenac and ketoprofen to relieve pain after maxillofacial surgery was compared in the present study. In a randomized and double-blind fashion, 90 ASA I–II patients (16–60 yrs) were studied, divided into three groups: Thirty patients received 1.0 mg · kg^?1 diclofenac i.v. after general anaesthesia induction, before surgical incision, and four hours later the same dose was given i.m. Thirty patients received ketoprofen 1.35 mg · kg^?1 i.v. and i.m., as above, and a third group of 30 patients received a comparable volume of saline i.v. and i.m. The patients received supplemental analgesia using a patient controlled analgesia apparatus; the rescue medication consisted of 0.03 mg · kg^?1 oxycodone i.v. (four-hour maximum dose was 0.4 mg · kg^?1) during the 24-hour follow-up. The three groups were comparable regarding the type of maxillofacial surgery (osteotomies vs. soft tissue surgery). Overall, there was a lower need for i.v. oxycodone during the 24-hour period in the diclofenac group (269 doses) than in the ketoprofen group and in the saline group (388 doses, each) (P<0.01). The significantly lower number of oxycodone administrations in the diclofenac group was a result of a distinguishable difference, particularly during the first four hours after surgery. There was no statistically significant difference in the incidence of side effects of the analgesic therapy between the three groups.     

Comparison of sevoflurane and propofol for ambulatory anaesthesia in gynaecological surgery

PURPOSE: To analyse the cost-efficiency ratio of sevoflurane compared with propofol for gynaecological ambulatory anaesthesia. METHODS: In a prospective randomised study 52 ASA I patients scheduled for ambulatory pregnancy termination were premedicated with lorazepam and received alfentanil prior to anaesthesia induction with propofol (group P, n = 26) or with sevoflurane 8% (group S, n = 26) using the single breath vital capacity technique. Anaesthesia was maintained with N2O in both groups supplemented with sevoflurane (group S) or propofol boluses (group P). RESULTS: The quality of induction and maintenance of anaesthesia was similar between groups except for the incidence of movement during anaesthesia (14/26 patients in group P and 4/26 in group S, P < 0.05). The incidence of post-operative emesis was increased in the sevoflurane group (P < 0.05) but the patients felt able to perform normal activity after a similar delay (18.4 +/- 2.9 hr vs 20.6 +/- 2.8 hr, P > 0.05). The direct cost of anaesthesia was lower in the sevoflurane group (679 FF, n = 24 vs 1153 FF, n = 2-5 in propofol group) but the weight of uterine aspiration products was higher (293 +/- 66 g, median = 230 g, Range 110-800 g, n = 13 vs 108 +/- 8 g, median = 110 g, Range 60-160 g, n = 12, group S vs group P respectively, P = 0.004). Four patients needed reoperation and ambulatory anaesthesia failed in six patients because of uterine haemorrhage. CONCLUSION: Ambulatory anaesthesia with sevoflurane offers a good alternative to propofol but further investigation concerning blood loss with sevoflurane needs to be performed in gynaecological practice.     

Mirtazapine premedication: Effect on preoperative anxiety and propofol dose requirements at different stages of hypnosis

BackgroundMirtazapine is an antidepressant drug that blocks central 5-HT2 receptors with anxiolytic and sleep-promoting effects and theoretically can be used as a premedication.MethodsSixty ASA I-II patients aged 25–50 yr were randomly allocated according to the premedication received 2 h before induction of anesthesia into two equal groups: group M patients received mirtazapine 30 mg tablet mixed with 20 ml of water and group P patients received 20 ml of plain water. Anxiety level was measured by visual analogue scale (VAS) and bispectral index (BIS) electrodes were connected before induction of anesthesia. Intravenous (i.v) infusion of propofol 1% at a rate of 300 ml h^?1 was started to induce hypnosis till a target BIS value of 45 (BIS45) is reached, and then endotracheal intubation is performed after fentanyl and cis-atracuruim being administered. Propofol dose requirements to achieve loss of response to verbal contact (RVC), loss of eyelash reflex (ELR), and a target BIS45 were recorded. Anesthesia was maintained with sevoflurane titrated to BIS value of 40–50 and oxygen/air mixture. Recovery time was recorded. In postanaesthesia care unit (PACU), VAS for pain and Ramsay sedation score were recorded. Patients were discharged from PACU when two consecutive Aldrete scores of 9 or 10 are obtained, and time of PACU stay was recorded.ResultsPreoperative anxiety by VAS and propofol doses required achieving loss of RVC and ELR, and target BIS45 were significantly lower in mirtazapine group. The two groups were comparable with regard to recovery and PACU stay times as well as postoperative pain and anxiety.ConclusionMirtazapine 30 mg oral tablets can be used as a premedication as it reduces preoperative anxiety and hypnotic dose requirements of propofol, and does not prolong recovery time.