Recovery from propofol infusion as the main agent for outpatient arthroscopy

Propofol by continuous intravenous infusion has been compared with isoflurane as the main anaesthetic agent for outpatient arthroscopy of the knee. In 40 unpremedicated patients, anaesthesia was induced with propofol 2 mg/kg and vecuronium bromide 0.1 mg/kg and maintained after tracheal intubation with nitrous oxide 66% in oxygen. One group received 3% isoflurane prior to intubation and 0.9% during maintenance, while the other received a continuous intravenous infusion of propofol at a rate of 10 mg/kg/hour. Recovery was assessed by the time to opening eyes, to be able to answer five questions correctly, to recovery of ocular balance (Maddox Wing test) and by comparing pre- and postoperative performance in a paper and pencil test (the p-deletion test). After 3 hours all the patients were fit for discharge. Recovery tests showed no differences between the groups. All patients were satisfied with the anaesthesia. Full recovery took on average 1.5 days (range between 1 hour and 14 days) in both groups. Patients' opinion 1 month after the procedure should be included in every study concerning recovery. Anaesthesia by continuous propofol infusion results in quick recovery comparable with that following isoflurane anaesthesia.     

Total intravenous versus inhalational anaesthesia for colonoscopy: a prospective study of clinical recovery and psychomotor function

A randomized, prospective study was conducted on 69 patients comparing recovery after two different anaesthetic techniques for ambulatory colonoscopy. Thirty-five patients received an intravenous fentanyl (1 microg/kg), midazolam (0.05 to 0. 075 mg/kg) and propofol (10 to 20 mg boluses as required) combination. 34 patients received sevoflurane in 67% nitrous oxide. Drug administration was titrated to clinical signs. At baseline and 30, 60, 90 and 120 minutes after the procedure patient performance on a comprehensive battery of psychomotor tests was recorded. Emergence times were noted. Depth of sedation was assessed at 5 minute intervals for 30 minutes after the end of the procedure. Emergence times were faster in the fentanyl/midazolam/propofol group by 2.2 minutes. A lower sedation score was detected at 20 minutes in the sevoflurane/nitrous oxide group. Psychomotor impairment was of a greater magnitude and more prolonged by 30 to 90 minutes in the fentanyl/midazolam/propofol group. It is concluded that a sevoflurane/nitrous oxide anaesthetic has a suitable recovery profile for ambulatory colonoscopy and results in faster recovery of cognitive function compared with a fentanyl, midazolam and propofol combination.     

A comparison of two different doses of ketamine with midazolam and midazolam alone as oral preanaesthetic medication on recovery after sevoflurane anaesthesia in children

BACKGROUND: This investigation prospectively evaluated the effect of oral premedication of two different doses of ketamine with midazolam and midazolam alone on the recovery of children after sevoflurane anaesthesia. METHODS: In a randomized, double-blind study, 79 children (aged 1-8 years, ASA physical status I or II) were assigned to receive one of three premedications in a volume of 0.5 ml x kg(-1): group 1 received midazolam 0.5 mg x kg(-1) (MD); group 2 received midazolam 0.5 mg x kg(-1) with ketamine 1.8 mg x kg(-1) (MK-1); and group 3 received midazolam 0.5 mg x kg(-1) with ketamine 3 mg x kg(-1) (MK-2). The reactions of the children during administration were noted. Anaesthesia was induced by facemask with incremental sevoflurane administration. All children received alfentanil (15 micro g x kg(-1)). Tracheal intubation was facilitated by mivacurium (0.2 mg x kg(-1)). Anaesthesia was maintained with sevoflurane and an additional dose of alfentanil, if necessary. During recovery, the time interval between discontinuation of anaesthesia and arousal (spontaneous ventilation, extubation) were recorded. RESULTS: Emergence (spontaneous ventilation, extubation) and recovery times (discharge, Aldrete score=9) did not differ significantly between groups (P=0.24, P=0.59 and P=0.145, respectively). CONCLUSIONS: The combination of midazolam and ketamine as oral preanaesthetic medication did not significantly affect the recovery time of children after sevoflurane anaesthesia.     

Comparison of propofol and thiopentone for induction of anaesthesia in premedicated patients

Thirty premedicated ASA I or II patients scheduled for minor gynaecological surgery, were randomly allocated to receive either 1.5 mg/kg or 2 mg/kg propofol of the new emulsion formulation, or 4 mg/kg thiopentone, given over 20 seconds. Anaesthesia was successfully induced in all 30 patients. The mean (SEM) induction times were for propofol 1.5 mg/kg 33.3(3.2) seconds, for 2 mg/kg 30.5(2.7) seconds and for thiopentone 34.6(2.7) seconds. The incidence of apnoea greater than 10 seconds, was respectively 60, 80 and 80%, and the mean duration of apnoea 30.8(5.3), 37.1(5.0) and 23.7(5.0) seconds. The mean systolic blood pressure decreased after propofol 1.5 mg/kg by 16.0 mmHg, after 2 mg/kg by 18.6 mmHg, and increased after thiopentone by 1 mmHg, 2 minutes after injection. Heart rate increased significantly 2 minutes after thiopentone by an average of 15.1 beats/minute, but not after propofol. Pain was not reported during or after the injection. No major adverse reactions occurred at induction or during maintenance of anaesthesia with an inhalation agent. One patient who received 2 mg/kg propofol and isoflurane vomited for 24 hours. The recovery of anaesthesia after propofol induction, was quicker than after thiopentone.     

Anaesthesia for magnetoencephalography in children with intractable seizures

BACKGROUND: Magnetoencephalography (MEG), a noninvasive technique for evaluation of epileptic patients, records magnetic fields during neuronal electrical activity within the brain. Anaesthesia experience for MEG has not yet been reported. METHODS: We retrospectively reviewed records of 48 paediatric patients undergoing MEG under anaesthesia. Thirty-one patients (nonprotocol group) were managed according to the anaesthesiologist's discretion. Premedication included oral midazolam, chloral hydrate or fentanyl oralet, intravenous midazolam or inhalational anaesthesia with sevoflurane. Anaesthesia was maintained with propofol, midazolam, fentanyl, alone or in combination. A subsequent protocol group (17 patients) received chloral hydrate as premedication and propofol for maintenance of anaesthesia. RESULTS: There was an overall 25% failure of interictal activity and localization on the MEG scan. In the nonprotocol group, 11 scans failed (35.5%). Of these, eight (72.7%) received midazolam orally. Only one failure (5.8%) was recorded in the protocol group in a patient who received chloral hydrate as sedation supplemented by sevoflurane. CONCLUSIONS: In our experience, midazolam premedication resulted in a high MEG failure rate (73%). Chloral hydrate premedication and propofol maintenance resulted in a lower incidence of MEG failure (5.8%). General anaesthesia with a continuous infusion of propofol or sevoflurane appears acceptable, although, lighter levels of anaesthesia might be required to avoid interference with interictal activity of the brain.     

Cardiovascular effects of sedative infusions of propofol and midazolam after spinal anaesthesia

The cardiovascular effects of intravenous sedation were studied in fifty patients after spinal anaesthesia for lower limb or pelvic surgery. Twenty patients received propofol (mean dosage 74 (SD 4) micrograms/kg/min for 0-20 minutes and 51 (SD 7) micrograms/kg/min for 20-40 minutes), twenty received midazolam (35 micrograms/kg + 2.54 (SD 0.2) micrograms/kg/min for 0-20 minutes and 1.35 (SD 0.2) micrograms/kg/min for 20-40 minutes) and ten patients received saline infusion only. The forearm vasoconstriction in response to the spinal anaesthesia was measured by strain gauge plethysmography. Spinal anaesthesia lowered systolic and diastolic blood pressure by 18 (SED 4) mmHg and 9 (SED 2) mmHg respectively. (SED = standard error of the difference.) This was associated with a 32% decrease in mean forearm blood flow. Propofol and midazolam caused similar additional reductions in systolic and diastolic blood pressure (10 (SED 4) mmHg and 4 (SED 2) mmHg) and a decrease in heart rate (P less than 0.005), but forearm vasoconstriction was not altered. In the control group, however, forearm vasoconstriction increased during 40 minutes in theatre (P less than 0.05). Recovery from propofol was far more rapid than after midazolam and was virtually complete in ten minutes. This was reflected by an increase in blood pressure and in forearm vasoconstriction in the recovery period.     

Recovery from fixed–dose midazolam–induced anaesthesia and antagonism with flumazenil for outpatient arthroscopy

This study evaluated recovery after a fixed dose of midazolam as induction agent and the influence of flumazenil on recovery parameters in patients undergoing day-case surgery (arthroscopy of the knee). In 40 unpremedicated patients, anaesthesia was induced with midazolam 0.2 mg/kg, vecuronium bromide 0.1 mg/kg intravenously and 3 vol.% isoflurane in oxygen prior to intubation. Anaesthesia was maintained with nitrous oxide 66% in oxygen and 0.9 vol.% isoflurane. Ten minutes after the end of anaesthesia 20 patients received 0.2 mg flumazenil intravenously, followed by increments of 0.1 mg at 60 s intervals until eye opening. Recovery was assessed by the time to eye-opening, to answering five set questions correctly, and to recovering ocular balance (Maddox Wing test), and by comparing pre- and postoperative performance in a pencil and paper test (the p-deletion test). With the exception of ocular balance, all parameters showed a quicker improvement without side-effects in the flumazenil group. After 4 h all patients were fit for discharge. One month after the procedure, all patients were satisfied with the anaesthesia. Full recovery took on average 1.5 days (range between 0 h-10 days). Whilst the technique employing a fixed dose of midazolam as induction agent gives satisfactory intraoperative anaesthesia for day-case arthroscopy, further improvement can be made with the use of flumazenil which hastens recovery.     

A combination of fentanyl-midazolam-propofol provides better intubating conditions than fentanyl-lignocaine-propofol in the absence of neuromuscular blocking agents

BACKGROUND: The use of propofol and adjuvants such as opioids, benzodiazepines and local anaesthetic agents, may provide adequate conditions for tracheal intubation without the need for neuromuscular blocking agents. In this randomized, double-blind study, intubating conditions after induction of anaesthesia with propofol, midazolam and fentanyl were compared with those after propofol, lignocaine and fentanyl. METHODS: In 80 ASA I/II adult patients undergoing elective gynaecological surgery, intubating conditions were compared after induction of anaesthesia with a fentanyl 2 microg/kg, midazolam 0.03 mg/kg, propofol 2.5 mg/kg combination (group FMP) vs. a fentanyl 2 microg/kg, lignocaine 1.5 mg/kg, propofol 2.5 mg/kg combination (group FLP). Intubating conditions were assessed using a qualitative scoring system. RESULTS: Intubation was successful in all patients in group FMP and in 87.5% of patients in group FLP; (P= 0.021). Overall, intubating conditions were clinically acceptable in 77.5% and 55% of patients in group FMP and group FLP, respectively (P= 0.033). CONCLUSION: We conclude that the fentanyl, midazolam, propofol combination more reliably provides acceptable conditions for intubation than the fentanyl, lignocaine, propofol combination. Intubation was successful in all patients receiving the fentanyl, midazolam, propofol combination.     

Propofol auto-co-induction as an alternative to midazolam co-induction for ambulatory surgery

We propose the use of an intravenous propofol/propofol auto-co-induction technique as an alternative to propofol/midazolam for induction of anaesthesia. We have studied 54 unpremedicated ASA 1 or 2 patients undergoing day-stay anaesthesia for minor orthopaedic surgery. All received 10 micrograms.kg-1 or alfentanil before induction, followed by either midazolam 0.05 mg.kg-1, propofol 0.4 mg.kg-1 or saline, and 2 min later, a propofol infusion at a rate of 50 mg.kg-1.h-1 until loss of eyelash reflex. We compared pre- and postinduction haemodynamic changes, complications at insertion of a laryngeal mask airway and recovery from anaesthesia in the three groups. Both co-induction techniques showed less postinduction hypotension and significant reduction of the total induction dose of propofol when compared to the control group. In the propofol/propofol group there was a decreased incidence of apnoea during induction of anaesthesia. These patients were discharged from hospital 2 h after the end of anaesthesia whereas patients in the midazolam/propofol group were discharged after 2 1/2 h (p < 0.001).     

Intra-operative patient-controlled sedation

Propofol and midazolam were compared for intra-operative patient-controlled sedation in 40 ASA 1 day patients undergoing surgical extraction of third molar teeth under local anaesthesia. All patients initially received 0.7 micrograms.kg-1 fentanyl. Patients in the propofol group self-administered 20 mg (2 ml over 6 s) bolus doses of propofol; successful demands averaged 8.0 (SD 4.4) and unsuccessful demands (during the 1 min lockout period) 2.8 (SD 4.1). The midazolam group self-administered 0.5 mg (2 ml over 6 s) bolus doses and averaged 14.0 (SD 6.3) and 17.6 (SD 19.8) successful and unsuccessful demands respectively. Postoperative memory, measured with delayed free recall, and postoperative mental performance, measured with the frequency accrual speed test index, were both significantly less impaired in the propofol group. Although there was no significant difference in patient satisfaction, measured postoperatively, propofol was judged the more suitable agent for patient-controlled sedation, because of its more rapid response to fluctuating intra-operative requirements, superior recovery characteristics and beneficial effect on mood.     

Propofol versus midazolam. Long-term sedation in the intensive care unit]

Sedative-analgesic treatment of patients on long-term artificial ventilation aims at protection from stress related to their disease or therapy. By stabilising both the patient's vital functions and psychological state this treatment may contribute to therapeutic success. The choice of drugs depends primarily on the nature and course of the underlying disease. Midazolam and propofol are available as hypnotics for short-term sedation during the post-operative period. The purpose of this study was to evaluate the effects of both agents on cardiovascular function, cortisol production, lipometabolism, and the recovery period following 24-h sedation. METHODS. Twenty female patients (mean body weight: 72 kg, mean age: 60 years) were randomly assigned to receive either midazolam or propofol over 24 h following major abdominal surgery. Balanced anaesthesia (halothane/O2/N2O/fentanyl) was administered for the surgical procedure. Assisted ventilation was used in all patients during the post-operative sedation period. Sedation depth was maintained at III-IV on the Ramsey scale. On arrival in the intensive care unit (ICU), an initial i.v. bolus of midazolam 0.1 mg/kg or propofol 1 mg/kg was followed by a continuous infusion (midazolam: 0.1 mg/kg.h; propofol: 2 mg/kg.h). Supplementary boluses of one-half the initial dose were given if required. Post-operative analgesia was achieved with 3 mg intravenous piritramide at 2-h intervals. A 7F Swan-Ganz catheter was inserted in the pulmonary artery and haemodynamic and biochemical parameters were monitored at 4-h intervals over 24 h starting 2 h after arrival in the ICU. Catecholamines were measured by high-pressure lipid chromatography (HPLC), cortisol by radioimmunoassay, midazolam by HPLC and ultraviolet detection, and propofol by HPLC and fluorescence detection. Data were calculated as means. The statistical analysis was performed according to the Mann-Whitney test, and significance was accepted for P less than 0.05. RESULTS. On administration of the propofol bolus at the onset of sedation, a decrease in blood pressure was particularly observed in patients with masked hypovolaemia, however, this decrease was easily controlled by volume administration. Independent of the type of sedation, the haemodynamic parameters remained unchanged throughout the observation period. At all times of measurement the mean heart rate was lower in the propofol group (90/min) when compared with the midazolam group (100/min), however, this difference did not reach significance. There were also no significant differences in cardiac index at all times of measurement, although it increased in both groups within the first 12 h by 0.6 l/min.min2. In both groups this increase was associated with a reduction in peripheral resistance and an increase in rectal temperature. To achieve the desired sedation depth, midazolam was administered at a mean dosage of 0.11 mg/kg.h and propofol at 1.9 mg/kg.h. Catecholamine levels decreased in both groups within the first 8 h: after 8 h of sedation the plasma levels of noradrenaline and adrenaline were 525 and 65 pg/ml, respectively, in the midazolam group and 327 and 51 pg/ml in the propofol group. (ABSTRACT TRUNCATED AT 400 WORDS)     

Prophylactic use of midazolam or propofol at the end of surgery may reduce the incidence of emergence agitation after sevoflurane anaesthesia

Sevoflurane is associated with a high incidence of emergence agitation in children. Midazolam and propofol have been examined with the aim of reducing emergence agitation after sevoflurane anaesthesia. However the effect of both drugs on emergence agitation is still controversial. Therefore we designed this study to measure the effect of midazolam or propofol at the end of surgery on emergence agitation during the recovery period. One hundred and one children, aged one to 13 years, undergoing strabismus surgery were enrolled in this randomised double-blind study. Anaesthesia was induced and maintained with sevoflurane in N2O/O2. Children were randomly assigned to receive midazolam 0.05 mg/kg (group M, n = 35), propofol 1 mg/kg (group P, n = 31) or saline (group S, n = 35). A four-point scale was used to evaluate recovery characteristics upon awakening and during the first hour after emergence from anaesthesia. The incidence of emergence agitation in group M was 42.9% (15/35), in group P 48.4% (15/31) and in group S 74.3% (26/35). The incidence of emergence agitation in groups M and P was significantly less than in group S. The emergence time was prolonged for patients in groups M and P compared to group S. There was no significant difference in the incidence of emergence agitation or in emergence times between the groups P and M. We conclude that propofol or midazolam administration before the end of surgery may be effective in reducing the incidence of emergence agitation in children undergoing strabismus surgery under sevoflurane anaesthesia.     

Ketamine and midazolam is an inappropriate preinduction combination in uncooperative children undergoing brief ambulatory procedures

BACKGROUND: We prospectively studied the effects of intramuscular (i.m.) ketamine alone, or combined with midazolam, on mask acceptance and recovery in young children who were uncooperative during induction of anaesthesia. METHODS: The Institutional Review Board (IRB) approval was obtained to study 80 children, 1-3 years, scheduled for bilateral myringotomies and tube insertion (BMT). Mask induction was attempted in all the children. Those who were uncooperative were randomly assigned to one of the four preinduction treatment groups: group I, ketamine 2 mg.kg(-1); group II, ketamine 2 mg.kg(-1) combined with midazolam 0.1 mg.kg(-1); group III, ketamine 2 mg.kg(-1) with midazolam 0.2 mg.kg(-1); or group IV, ketamine 1 mg.kg(-1) with midazolam 0.2 mg.kg(-1). Anaesthesia was continued with nitrous oxide and halothane by facemask. RESULTS: Children in all treatment groups achieved satisfactory sedation in less than 3 min following the administration of the preinduction drug(s). Compared with patients who received halothane induction (comparison group), the use of ketamine alone did not significantly (P > 0.0167, a Bonferroni corrected significance level) delay recovery and discharge times (18.8 +/- 2.5 and 82.5 +/- 30.7 min vs 12.6 +/- 4.6 and 81.0 +/- 33.8 min, P = 0.030 and P = 0.941, respectively). Patients who received ketamine/midazolam combinations, however, had significantly longer recovery and discharge times vs halothane (32.3 +/- 14.0 and 128.0 +/- 36.6 min, P = 0.001, P = 0.007, respectively). These times were so clinically unacceptable, that the study had to be terminated with only 17 patients receiving study drugs. CONCLUSIONS: It is concluded that ketamine/midazolam combination is not appropriate for preinduction of anaesthesia in paediatric ambulatory patients because of unacceptably prolonged recovery and delayed discharge times.     

丙泊酚复合咪唑安定和/或芬太尼在胆道镜操作过程中的镇静作用

目的研究丙泊酚复合咪唑安定和/或芬太尼用于胆道镜操作过程中的镇静效果。方法选择18~65岁行胆道镜的患者90例,随机分为三组:PF组(n=31),首次静注芬太尼0.05 mg+丙泊酚1 mg/kg;PM组(n=29),首次静注咪唑安定2 mg+丙泊酚1 mg/kg;PMF组(n=30),首次静注芬太尼0.05 mg+咪唑安定2 mg+丙泊酚1 mg/kg。各组根据需要追加丙泊酚每次20~30 mg。记录心率、血压、脉搏血氧饱和度、镇静分级,观察患者症状及记忆缺失情况。结果用药后1 min三组患者都能达到满意的镇静效果(镇静分级2~3级);所有患者停药后17 min完全清醒,PF组恢复时间最短(P<0.01),但有21例(67.7%)对操作过程有记忆,只有15例(48.4%)患者对麻醉镇静的方法感到很满意。结论丙泊酚复合咪唑安定和/或芬太尼在胆道镜操作中镇静效果更好,无明显不良反应。     

Induction characteristics of propofol in children: comparison with thiopentone

The induction characteristics of propofol were studied and compared with thiopentone in children aged 3-14 years who received either no premedication or pethidine-atropine or trimeprazine. Anaesthesia was maintained with nitrous oxide in oxygen, and isoflurane. The induction doses of propofol and thiopentone were 2.9 mg/kg and 6.5-7.1 mg/kg respectively; premedication had no significant effect on the induction doses of either agent. Spontaneous movement and hypertonus occurred in about 20% of children with both agents. The use of propofol was associated with a high incidence of pain on injection (injections were mostly in veins on the dorsum of the hand), but this was reduced by mixing lignocaine with propofol. Cardiovascular effects were not clinically significant with either agent. Apnoea occurred in 35% of patients given propofol and in 50% of those given thiopentone. Children anaesthetised with propofol awoke significantly earlier after cessation of all anaesthesia. It is concluded that the use of propofol is safe in children and may have advantages where early recovery from anaesthesia is desirable, but offers no advantage over thiopentone for routine induction of anaesthesia.     

No additional analgesic effect of intra-articular morphine or bupivacaine compared with placebo after elective knee arthroscopy

Background: Intra-articular pain prophylaxis is a controversial measure, adding costs although the benefits are still disputed. We wanted to evaluate the effects of intra-articular opioid or local anaesthesia or a combination of the two on postoperative analgesia and analgesic consumption after elective knee arthroscopy.
Methods: 107 patients with little or no preoperative pain and a minor surgical procedure were studied in a prospective, randomized double-blind design. The patients received midazolam 0.03 mg/kg intravenously before induction of general anaesthesia with fentanyl 1–2 μg/kg and propofol 2.0 mg/kg intravenously. Anaesthesia was maintained by a total intravenous technique with propofol infusion supplemented with alfentanil 10 μg/kg when needed. The patients breathed oxygen/air through a laryngeal mask. By the end of the surgery they received 20 ml of test drug into the knee-joint: Group I (BM): 20 ml of bupivacaine 2.5 mg/ml with 3 mg of morphine; Group II (B): 20 ml of bupivacaine 2.5 mg/ml; Group III (M): 20 ml isotonic saline with 3 mg morphine; Group IV (P): 20 ml of isotonic saline (placebo).
Results: There were no significant differences between the groups in: time to first analgesic administered, analgesic consumption during the pre-or post-discharge period, nausea, somnolence, side-effects or postoperative pain perception during the first week.
Conclusions: Intra-articular administration of morphine or bupivacaine is not indicated after elective knee-arthroscopy in patients with minor pre-operative pain and a small surgical trauma.     

Midazolam/propofol but not propofol alone reversibly depress the swallowing reflex

General anaesthetics depress swallowing and this is a reason to delay oral intake after general anaesthesia. The swallowing reflex was studied 2 h after general anaesthesia for patients undergoing colonoscopy. Forty–one patients were anaesthetized with midazolam 75 μgkg^-1 followed by a continuous infusion of propofol and 39 patients with propofol 1.5 mgkg^-1 bolus followed by an infusion. Swallowing reflex was measured by electromyography 2 h after induction of anaesthesia, before and 5 min after the administration of flumazenil (0.2 mg) or placebo. Two h after anaesthesia, the state of consciousness was almost normal in all patients and did not change after flumazenil. At two hours, the latency times for the swallowing reflex in patients treated with propofol alone were of 1.4 ± 0.4 s and were significantly shorter ( P < 0.05) than the value of 1.9 ± 0.8 s observed in patients who received midazolam with propofol. In the latter group the latency time of the swallowing reflex was significantly reduced following the administration of flumazenil but not placebo. In patients who received propofol without midazolam, the administration of flumazenil or placebo was not associated with significant changes in the latency times. There were also no significant differences in the latency times in the subgroup that received midazolam followed by flumazenil and the propofol alone groups that did or did not receive flumazenil. These results suggest that midazolam still exerts a depressive effect on the swallowing reflex 2 h after its administration despite the recovery of normal consciousness.     

Remifentanil-Propofol- versus Fentanyl-Midazolam-Kombination bei intrakraniellen Eingriffen

INTRODUCTION: After neurosurgery patients often need to be sedated and ventilated in the intensive care unit (ICU). However, rapid postoperative recovery and neurological examination are particularly important for the early recognition of complications. In this retrospective study two different strategies of anaesthesia technique and ICU sedation (fentanyl-midazolam versus remifentanil-propofol) were compared. METHODS: Intraoperatively, patients received continuous infusions of either fentanyl (0.2-1.0 mg/h) and midazolam (2-10 mg/h) or remifentanil (0.2-0.5 microg/kg body weight/min) and propofol (3-6 mg/kg body weight/h). After arrival in the ICU fentanyl (0.03-0.2 mg/h) and midazolam (2-12 mg/h) or remifentanil (0.1-0.2 microg/kg body weight/min) and propofol (0.5-3 mg/kg body weight/h) were infused to reach a Ramsay score of 4. The times between termination of infusion and extubation and the length of stay in the ICU were examined. RESULTS: A total of 60 patients (n=30 each group) undergoing supratentorial brain tumour surgery were enrolled. The groups were comparable for age, weight, ASA status (American Society of Anesthesiologists) and duration of drug administration (remifentanil-propofol 528+/-382 min versus fentanyl-midazolam 548+/-360 min). Extubation times were significantly shorter after remifentanil-propofol (47 min) than after fentanyl-midazolam (481 min), and the length of stay in the ICU was also significantly reduced (1.8 days versus 3.7 days). As a result of prolonged unconsciousness and impaired neurological assessability, a brain CT scan was necessary in 3 patients after fentanyl-midazolam to exclude neurosurgical complications. CONCLUSION: This retrospective study demonstrates that remifentanil-propofol anaesthesia and ICU sedation are superior to the combination of fentanyl and midazolam in terms of ventilation time and length of ICU stay. Moreover, the use of fentanyl-midazolam may lead to unnecessary CT scans.     

Implantable cardioverter-defibrillator placement in patients with mild-to- moderate left ventricular dysfunction: hemodynamics and recovery profile with two different anesthetics used during deep sedation

OBJECTIVE: To compare the effects of thiopental and propofol during defibrillation threshold testing (DFT) on hemodynamics and recovery profile in patients requiring automatic internal cardioverter-defibrilator placement. DESIGN: Prospective clinical investigation. SETTING: University hospital. PARTICIPANTS: Thirty-four adult patients. INTERVENTIONS: After administration of midazolam, 0.025 mg/kg, and fentanyl, 0.5 to 1 mug/kg, surgery was performed under topical infiltration with 1% lidocaine. In group I (GI) (n = 17), patients received thiopental by slow injection and patients in group II (GII) (n = 17) received propofol before induction of ventricular fibrillation (VF). MEASUREMENTS AND MAIN RESULTS: Patients received 4.1 +/- 1.4 mg of midazolam, 114 +/- 34 mug of fentanyl, and 280 +/- 78 mg of thiopental in GI; and 4.6 +/- 1.7 mg of midazolam, 119 +/- 62 mug of fentanyl, and 147 +/- 40 mg of propofol in GII (p > 0.05). Hemodynamics did not show significant differences between the groups at any recording time. Average time needed to regain the pretest sedation level was 16.4 +/- 8.8 minutes in GI and 10.9 +/- 5.5 minutes in GII (p = 0.03). Time required to achieve a score of 10 using a modified Aldrete score was 26.4 +/- 9.3 minutes in GI and 17.4 +/- 4.9 in GII (p = 0.001). Seven patients in GII (41%) and 1 patient in GI (6%) became hypotensive after DFT (p = 0.04). CONCLUSIONS: Deepening the sedation level by slow injection of thiopental or propofol before DFT provided satisfactory conditions during brief episodes of VF. Delay in recovery of arterial pressure after DFT with propofol and delay in arousal and discharge of patients with thiopental are major disadvantages of the regimens.     

不同剂量咪达唑仑与异丙酚催眠效应的相互作用

目的 评价不同剂量咪达唑仑与异丙酚催眠效应的相互作用.方法 择期全麻病人120例,ASA Ⅰ或Ⅱ级,年龄18～60岁,体重40～80 kg,随机分为4组(n=30),各组分别随机分为6个亚组,M组和P组各亚组分别静脉注射咪达唑仑0.04、0.06、0.08、0.10、0.12、0.15 mg/kg、异丙酚0.8、1.0、1.2、1.5、1.8、2.2 mg/kg;MP1组和MP2组各亚组分别按咪达唑仑与异丙酚ED50等效比1:13(咪达唑仑剂量分别为0.022、0.028、0.033、0.039、0.044、0.055 mg/kg)和临床常用比例1:10(咪达唑仑剂量分别为0.03、0.04、0.045、0.05、0.055、0.06 mg/kg)行麻醉诱导.M组、P组、MP1组和MP1组分别于注药后3、1,1、1 min时行警觉,镇静(OAA/S)评分,催眠有效标准:OAA/S评分≤2分.采用加权概率单位法计算半数有效剂量(ED50)及其95%可信区间(95%CI);采用等辐射分析法判断两药催眠效应的相互作用.结果 M组、MP1.2组咪达唑仑催眠效应的ED50及其95%CI分别为0.088(0.066～0.110)、0.031(0.026～0.036)、0.045(0.040～0.049)mg/kg;P组、MP1.2组异丙酚催眠效应的ED50及其95%CI为1.142(0.933～1.350)、0.421(0.343～0.480)、0.450(0.399～0.491)mg/kg.结论 麻醉诱导时咪达唑仑与异丙酚按ED50等效剂量比1:13给药,两药催眠效应为协同作用;按临床常用剂量比1:10给药时两药催眠效应为相加作用.