Recovery after anesthesia with propofol in otorhinolaryngologic surgery of brief duration

This study was designed to assess recovery from total intravenous anaesthesia with propofol for short ENT procedures. Twenty-six patients (ASA I and II) were assigned to two groups of thirteen: one breathed air (Laser laryngeal microsurgery), the second N2O-O2 (FIO2 : 0.5) (various ENT procedures). The induction sequence was exactly the same for both groups: oral premedication with 10 mg diazepam one hour before surgery, I mg pancuronium bromide, 2 micrograms X kg-1 fentanyl, denitrogenation within 3 min, after which propofol was delivered (2.5 mg X kg-1). When the eye-lash reflex had disappeared (time recorded), 1.5 mg X kg-1 suxamethonium was given and laryngotracheal intubation carried out. A continuous infusion of propofol (9 mg X kg-1 X h-1) was started. Surgery began 5 +/- 2 min after the start of propofol infusion. The durations of anaesthesia, surgery and propofol infusion were similar in both groups. To have good surgical conditions, it was necessary to give repeated doses of propofol for 15 patients. Thus, the total dose of propofol was significatively different between the two groups: 24.5 +/- 6.7 mg X kg-1 X h-1 in group "air" versus 16 +/- 3.6 mg X kg-1 X h-1 in group "N2O-O2" (p less than 0.001). Extubation occurred within 16 +/- 8 min in group "air", being more rapid in group "N2O-O2" (11 +/- 9 min; no significant difference). Recovery was assessed with two psychomotor tests: choice reaction time (CRT) and tracing test (TT).(ABSTRACT TRUNCATED AT 250 WORDS)     

Total intravenous anaesthesia with propofol or etomidate

In combination with fentanyl, propofol was compared with etomidate for total intravenous anaesthesia in 21 women (ASA Grades I-II) admitted for elective hysterectomy. They received either propofol (bolus 1.5 mg kg-1, infusion 9 mg kg-1 h-1 for 10 min thereafter 6 mg kg-1 h-1) or etomidate (bolus 0.10 mg kg-1, infusion 3 mg kg-1 h-1 reduced to 0.6 mg kg-1 h-1). Fentanyl 10 micrograms kg-1 was given for induction followed by an infusion of 30 micrograms kg-1 h-1 for 10 min reduced to 6 micrograms kg-1 h-1 for the first hour and successively reduced over time. Induction was smooth and maintenance easy to manage in both groups. There was no difference in time from end of infusion until extubation, but the time until the patients could report their date of birth was significantly shorter in the propofol group. Nausea and vomiting were more pronounced in the etomidate group, and mental side-effects were only seen after etomidate. After 3 months, more patients in the etomidate group complained of reduced power of concentration. We conclude that total intravenous anaesthesia with either propofol or etomidate is equally easy to manage, but in the recovery situation propofol was advantageous in time and quality.     

Comparison of propofol and methohexital for dental and maxillofacial surgery

A prospective study has been undertaken to compare a new intravenous anaesthetic agent, propofol, to methohexitone in 40 ASA I or II patients aged between 18 and 50 years undergoing maxillo-facial surgery and divided into two groups. Intramuscular premedication was standardized for all patients. In group I, propofol 2 mg X kg-1 was injected over 1 min in a peripheral venous line with fentanyl 0.86 microgram X kg-1, followed by an infusion of propofol 5 mg X kg-1 X h-1 and fentanyl 3 micrograms X kg-1 X h-1. In group II, the fentanyl dosage was the same as in group I, whilst methohexitone 3 mg X kg-1 was given for induction and 4.5 mg X kg-1 X h-1 for maintenance of anaesthesia. The following were recorded during induction, maintenance and recovery; haemodynamic parameters using a non invasive method; respiratory parameters; quality of anaesthesia; side-effects. Statistical analysis was performed using the Student t test and qualitative analysis using the Schwartz comparison test at 2%. The following results were found: the quality of anaesthesia with propofol was superior to that of methohexitone during the three stages of anaesthesia. The duration of induction was similar in both groups, but the quality of induction (occurrence of more minor side-effects; p less than 0.05) and intubation was in favour of propofol (p less than 0.05). During maintenance, stability of anaesthesia and a lesser incidence of side-effects were again in favour of the propofol group, in which a slower rate was also found (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

A clinical dose finding study of propofol in continuous total intravenous anesthesia]

Total intravenous anesthesia (TIVA) is recommended in view of avoiding air pollution. However, intermittent administration of anesthetic agents has a disadvantage of delayed emergence time. We have suggested continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp), and reported that the elder or the patients anesthetized for a long time show delayed emergence from continuous TIVA. In this study, after induction with propofol, ketamine, vecuronium and buprenorphine, the subjects were maintained with continuous intravenous administration of propofol corresponding to the age using twice step down method with ketamine (240 micrograms.kg-1.h-1), vecuronium (80 micrograms.kg-1.h-1) and buprenorphine (0.4 microgram.kg-1.h-1). Emergence was evaluated from the 2nd step down of propofol to awareness. There was a linear relationship between the emergence (2nd step down time of propofol to awareness) (Y) and the anesthetic time (X); Y = 0.175X + 3.00. We conclude that the last 1/6 (= 0.175) of anesthetic time is the point to reduce maintenance doses of propofol to achieve more rapid emergence.     

Recovery characteristics using isoflurane or propofol for maintenance of anaesthesia: a double-blind controlled trial

We studied 114 female patients (ASA 1 or 2) who were within 20% of ideal body weight and who were scheduled to undergo gynaecological laparoscopy which required supplementation with an opioid (groups IA and PA), or dental procedures which did not require opioid supplementation (groups IO and PO). A computerised package of psychomotor tests was performed before surgery. Anaesthesia was induced with propofol 2.5 mg.kg-1 and all patients received atracurium 0.3 mg.kg-1 and 67% nitrous oxide in oxygen. Patients in group IA received isoflurane 1% (inspired), and alfentanil 10 micrograms.kg-1 as a bolus and 10 micrograms.kg-1.h-1 as an infusion. Patients in group PA received propofol 9 mg.kg-1.h-1 as an infusion, decreasing to 6 mg.kg-1.h-1 after 15 min, together with alfentanil 10 micrograms.kg-1.h-1. Patients in groups IO and PO received isoflurane and propofol in the regimens described for groups IA and PA, but without alfentanil. Recovery was assessed by a blinded observer who recorded times to awakening (eye opening) and orientation (giving date of birth), and who repeated the psychomotor tests at 1, 3 and 5 h. Linear analogue scales of mood, nausea and pain were obtained and other side effects were noted in the succeeding 48 h. A matched control group of 25 females (who were not anaesthetised) underwent psychomotor testing on four occasions in order to assess the 'learning effect' of repeated recovery testing. The analysis of recovery tests did not assume a normal distribution.(ABSTRACT TRUNCATED AT 250 WORDS)     

胸腔镜胸交感神经切断术病人舒芬太尼复合异丙酚麻醉的效果

目的 评价胸腔镜胸交感神经切断术病人舒芬太尼复合异丙酚麻醉的效果.方法 择期行胸腔镜胸交感神经切断术的手汗症病人20例,ASA Ⅰ或Ⅱ级,静脉注射舒芬太尼0.5 μg/kg、异丙酚2.0～2.5 mg/kg和阿曲库铵0.6 mg/kg麻醉诱导,麻醉维持:静脉输注舒芬太尼0.2～0.3 μg·kg-1·h-1、异丙酚2～4 mg·kg-1·h-1,间断静脉注射阿曲库铵0.3 mg/kg.手术结束前30 min舒芬太尼输注速率减至0.1 μg·kg-1·h-1,异丙酚减至1～2 mg·kg-1·h-1.分别于麻醉诱导前(基础状态)、气管插管时、CO2充气时、CO2充气5 min、30min、放气后5min、拔管时记录SP、DP、HR,并于上述时点采集静脉血样,测定血浆皮质醇、醛固酮和血糖浓度,记录自主呼吸恢复时间、呼之睁眼时间和拔管时间.结果 术中SP、DP和HR波动在正常范围内;与基础值比较,血浆皮质醇、醛固酮和血糖浓度升高(P＜0.05),自主呼吸恢复时间、呼之睁眼时间和拔管时间分别为4.5±1.9、6.4±2.7、(12.6±1.5)min.结论 胸腔镜胸交感神经切断术病人舒芬太尼0.1～0.3 μg·kg-1·h-1复合异丙酚1～4mg·kg-1·h-1麻醉能维持血液动力学的稳定,可减轻应激反应.     

The effects of propofol anesthesia on local cerebral glucose utilization in the rat

The autoradiographic 14C-2-deoxy-D-glucose method was used to determine local cerebral glucose utilization (LCGU) during propofol anesthesia and recovery in 52 regions of the rat brain. Control rats intravenously received 5 ml.kg-1.h-1 of the egg-oil-glycerol emulsion that constitutes the vehicle for propofol. Anesthetized animals received an iv bolus of propofol (20 mg/kg) followed by continuous infusion of the anesthetic at 12.5, 25, or 50 mg.kg-1.h-1 for 1 h prior to injection of 14C-2-deoxy-D-glucose and for the following 45 min. In addition, a fifth group of animals were studied immediately after awakening from a 20 mg/kg bolus of propofol as indicated by the first reappearance of head lift. All rats were spontaneously breathing room air throughout the experimental procedure. The general pattern of the cerebral metabolic response to propofol anesthesia was a dose-related, widespread depression of LCGU. At the three infusion rates of propofol tested, overall mean LCGU was reduced by 33%, 49%, and 55%, respectively, and significant decreases were observed in 60%, 85%, and 90% of the regions assayed. These effects were rapidly reversible, since in the recovery group, LCGU returned to near control values in the majority of the brain areas. Although all of the anatomofunctional systems (sensorimotor, extrapyramidal, limbic, and reticular) were involved, forebrain structures showed a greater sensitivity to the depressant action of propofol than did hindbrain regions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Recovery and discharge of patients after long propofol infusion vs isoflurane anaesthesia for ambulatory surgery

Fifty unpremedicated patients scheduled for outpatient restorative dentistry and/or oral surgery lasting 2 to 4 h were anaesthetized with either propofol infusion or isoflurane inhalation. Before induction of anaesthesia with propofol (2.5 mg.kg-1), all patients were given 75 mg of diclofenac and 0.01 mg.kg-1 vecuronium intravenously. Intubation was facilitated with suxamethonium (1.5 mg.kg-1) and anaesthesia was maintained in random order either with propofol infusion (12 mg.kg-1.h-1 for the first 20 min, 9 mg.kg-1.h-1 for the next 20 min, and 6 mg.kg-1.h-1 for the rest of the anaesthesia) or with isoflurane (inspired concentration 1-2.5%), both with nitrous oxide and oxygen (30%). The patients breathed spontaneously using a non-rebreathing circuit. Patients given propofol infusion became re-orientated faster (11.0 +/- 5.5 min vs. 16.5 +/- 7.5 min; P less than 0.01) and at 30 min walked along a straight line better (P less than 0.01). At 60 min, none of the propofol patients displayed an unsteady gait, whereas 11 of the 25 isoflurane patients did (P less than 0.001). None of the patients receiving propofol had emesis at the clinic, compared with 10 of the 25 patients receiving isoflurane (P less than 0.001). The overall incidence of emesis was 2 of 25 and 14 of 25 in the propofol and isoflurane groups, respectively (P less than 0.01). Patients receiving propofol were discharged home earlier than patients receiving isoflurane (80 +/- 14 min and 102 +/- 32 min, respectively; P less than 0.01). It is concluded that propofol allows early discharge of patients, even after long anaesthesias.     

Effect of the association propofol-alfentanil on bronchial resistances in asthmatic patients

The bronchial resistances in 17 patients scheduled for ENT surgery were studied during general anaesthesia carried out with propofol and alfentanil. There were nine controls, all free from any allergic pathology. The other eight had bronchial hyperreactivity, with clinical asthma (one or two crises a month) treated with bronchodilators. Two had a complete Fernand-Widal syndrome, and the remaining six documented allergic asthma. All the patients were premedicated with hydroxyzine 2 mg.kg-1 orally on the eve of surgery, and two hours beforehand. Those patients who were on bronchodilators were given their drugs as usual with the premedication. Because bronchial resistances were measured with the patient breathing spontaneously (forced oscillation technique), induction was carried out in two steps, first with propofol 1.5 mg.kg-1, followed, two minutes later, by alfentanil 7 micrograms.kg-1. Once the bronchial resistances had been assessed the patient was given a further 2 mg.kg-1 dose of propofol, and alfentanil 40 micrograms.kg-1. The patient was then intubated, and anaesthesia maintained with propofol 9 mg.kg-1.h-1, and alfentanil 15 micrograms.kg-1 every fifteen minutes. In all, bronchial resistances were measured on the day before surgery, after premedication but before the patient had been given any anaesthetic drug, two minutes after the first injection of propofol, two minutes after the first injection of alfentanil, and after extubation. There were no significant differences between the two groups. Despite the small number of patients included in this study, it would seem that hydroxyzine, propofol and alfentanil may be used safely in patients with hyperreactive bronchi.     

A new method of continuous propofol infusion for total intravenous anesthesia]

Total intravenous anesthesia (TIVA) is recommended to avoid air pollution. However, intermittent administration of anesthetic agents has a large disadvantage of delayed emergence time. We suggested continuous TIVA with propofol, ketamine, vecuronium and buprenorphine (PKBp), and reported that maintenance with continuous intravenous administration of propofol corresponding to the age associated with ketamine (240 micrograms.kg-1.h-1), vecuronium (80 micrograms.kg-1.h-1) and buprenorphine (0.4 microgram.kg-1.h-1) brought rapid emergence and that the last 1/6 of anesthetic time was the point to reduce propofol maintenance dose. In this study, we maintained anesthesia with continuous intravenous administration of propofol using twice step down method every one hour. We conclude that the reduction of propofol maintenance dose for every 1/6 in one hour produces fewer dropout cases.     

Recovery from total intravenous anesthesia with propofol and buprenorphine

A retrospective study was performed to evaluate recovery from total intravenous anesthesia (TIVA) with propofol and buprenorphine for various types of surgery. The patients of the study were divided into two groups; Group A: n = 85, age 66 +/- 12 Y, duration 282 +/- 102 min, with epidural block and Group B: n = 56, 52 +/- 20 Y, 172 +/- 90 min, without the block. All patients were premedicated with intramuscular midazolam (1-5 mg). Anesthesia was maintained with propofol infusion with 40% oxygen in air, and an intravenous bolus dose of buprenorphine (0.11 +/- 0.03 mg). Muscle relaxation was obtained by intravenous vecuronium. The patients of Group A were supplemented with continuous epidural anesthesia using 2% mepivacaine. The maintenance dose of propofol (Group A: 4.5 +/- 1.2 mg.kg-1.h-1, Group B: 7.0 +/- 1.8 mg.kg-1.h-1) and temperature at the end of surgery decreased significantly with age. Awakening time in all patients was 12.3 +/- 7.4 min and it was correlated significantly with age and hypothermia, but not correlated with the maintenance dose or duration of propofol infusion. In short-duration surgery (within 2 hours, n = 36) awakening time was correlated with neither age nor temperature. There was no difference in awakening time between genders. Requirement for analgesics within 20 hours was 18.8% in Group A and 14.3% in Group B. Four patients (2.8%) reported dreaming, but none of the patients recalled the intraoperative events. We suggest that in elderly patients the reduction of intravenous anesthetics, maintenance of normothermia and short-duration surgery would result in rapid recovery in TIVA.     

Comparison of midazolam and propofol in combination with alfentanil for total intravenous anesthesia

Hemodynamic function during induction of anesthesia, the alfentanil and naloxone requirements, and the speed of recovery from total intravenous anesthesia with alfentanil/midazolam (group M, n = 10) or alfentanil/propofol (group P, n = 10) were compared in patients undergoing lower limb surgery. Twenty patients were randomly assigned to receive either 2 mg/kg propofol in 5 min followed by 9 mg.kg-1.h-1 for 30 min and 4.5 mg.kg-1.h-1 until skin closure, or 0.42 mg/kg midazolam in 5 min followed by 0.125 mg.kg-1.h-1 until skin closure. Simultaneously, a variable-rate infusion of alfentanil was given. Patients were ventilated with 30% oxygen in air. In both groups blood pressure and heart rate decreased significantly (P less than 0.02) and to a similar extent during induction. The total dose of alfentanil was similar in both groups. No patient in group P and nine patients in group M needed naloxone (average dose 130 +/- 70 micrograms, P less than 0.001). Recovery, as judged by psychomotor tests (90% score was reached at 1 h in the P group and at about 4 h in the M group, P less than 0.001), sedative scores, and orientation in time and place, was shorter in group P than in group M. The conclusion is reached that propofol is superior to midazolam in total intravenous anesthesia with alfentanil.     

Sedation with propofol and fentanyl in patients under intensive care]

This study investigated the efficacy of a constant rate infusion of propofol and fentanyl in thirty patients requiring artificial ventilation for more than 24 h. A loading dose, which differed according to the patient's age, was administered over a 30 min period: 2.5 mg.kg-1 for patients less than 50 (G1) (n = 9), 2 mg.kg-1 for patients between 50 and 60 years old (G2) (n = 9), and 1.5 mg.kg-1 for patients over 60 (G3) (n = 12). This was followed by an infusion of 3 mg.kg-1.h-1 in G1 and G2, and 2 mg.kg-1.h-1 in G3. A 1 microgram.kg-1.h-1 infusion of fentanyl was also given. The degree of sedation was assessed with the Ramsay scale before starting, after induction, and every four hours thereafter. When this proved to be insufficient, the dose of propofol was increased by 0.5 mg.kg-1.h-1 as well as that of fentanyl by 0.5 microgram.kg-1.h-1. Heart rate, mean arterial blood pressure, blood propofol, creatinine, transaminase and lipid levels, and urine output were measured before, during, and after the infusion. The blood propofol level increased during the infusion, being correlated to the doses given (r = 0.64, p less than 0.001). Sedation lasted 91.7 +/- 57.7 h. After stopping the infusion of propofol, mean recovery times were 7.5 +/- 5.9 min (G1), 11.4 +/- 11.4 min, and 14.4 +/- 13.5 min (G3) (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

The influence of age on hemodynamics and the dose requirements of propofol and buprenorphine in total intravenous anesthesia combined with continuous epidural anesthesia

A retrospective study was performed to determine the influence of age on hemodynamics and awakening time in total intravenous anesthesia (TIVA) using propofol and buprenorphine combined with continuous epidural anesthesia for abdominal surgery. Thirty-five patients (36-87 yr) were allocated to the following five groups by age: 36-49 yr, 50-59 yr, 60-69 yr, 70-79 yr and 80-87 yr. All patients were premedicated with midazolam i.m. Anesthesia was maintained with propofol infusion with 40% oxygen in air, intravenous buprenorphine plus vecuronium and continuous epidural anesthesia using 2% mepivacaine. After extubation, the epidural bolus dose (buprenorphine 0.1-0.2 mg with droperidol 1.25-2.5 mg) and epidural infusion (buprenorphine 17 micrograms.h-1 with droperidol 0.1 mg.h-1) were administered. Intraoperative heart rate (HR) and mean arterial pressure (MAP) decreased but remained within 30% of preanesthetic level. HR did not differ in five groups, although MAP decreased significantly in patients above 50 yr of age. The doses of midazolam (1-5 mg), propofol (2.7-7.4 mg.kg-1.h-1) and buprenorphine (40-200 micrograms) decreased with age (P < 0.01), while the maintenance doses of mepivacaine (40-140 mg.h-1) and vecuronium (0.03-0.09 mg.kg-1.h-1) showed no significant decrease. Awakening time was not significantly prolonged with age (r = 0.27, P = 0.12). Two patients in each group required analgesics within 20 hours. Neither nausea, respiratory depression nor awareness was found. We suggest that the combination of TIVA and continuous epidural anesthesia would be useful to maintain stable hemodynamic state and to obtain early recovery time, especially in the elderly.     

Comparative effects of thiopentone and propofol on respiratory resistance after tracheal intubation

To compare the effects of propofol and thiopentone on tracheal intubation-induced bronchoconstriction, 37 patients were allocated randomly to anaesthesia with either thiopentone 4 mg kg-1 followed by a 15-mg kg-1 h-1 continuous infusion or propofol 3 mg kg-1 followed by a 9-mg kg-1 h-1 continuous infusion. Intubation was facilitated by vecuronium 0.1-0.2 mg kg-1. Respiratory system resistance (Rrs) was measured by a CP-100 pulmonary function monitor, 5 min after intubation. The 5-min post-intubation Rrs values were significantly lower in the propofol group (8.5 (SD 1.5) cm H2O litre-1 S-1) than in the thiopentone group (10.9 (3.2) cm H2O litre-1 S-1). Thirty minutes after commencing isoflurane-nitrous oxide anaesthesia, Rrs declined by 17.5 (SEM 3.6)% from baseline in the thiopentone group, but by only 1.6 (2.6)% in the propofol group. We conclude that the dose of propofol administered provided more protection against tracheal intubation- induced bronchoconstriction than an induction dose of thiopentone.      

Electroencephalographic impact of propofol anesthesia

Two groups of patients were studied. In group A, propofol was used alone, given by repeat injections of 2.5 mg X kg-1 in 30 s, in 5 patients undergoing percutaneous thermocoagulation of the Vth cranial nerve. In group B, a series of 12 patients undergoing lumbar disc hernia surgery, propofol was given as a bolus of 2.5 mg X kg-1 in 60 s followed by an infusion of 7 to 12 mg X kg-1 X h-1 together with vecuronium and fentanyl. The EEG recording was carried out during the whole length of anaesthesia and for 1 h after its end. The recordings were all stereotyped, within five successive phases: the awake physiological pattern (phase 0) was desynchronized a mean 52 s after the start of the propofol injection; it was followed by an increase in amplitude of the alpha rhythm (phase I); within a mean of 132 s were seen phases II to V. Phase V corresponded to surgical anaesthesia and could be kept up by a rate of infusion of 9 mg X kg-1 X h-1 propofol. An increase in this rate gave rise to burst suppressions which lasted as much as 15 s or more, and disappeared very quickly when the infusion rate was slowed. After stopping the anaesthesia, the EEG phases were quickly reversed, V to 0: in a mean of 11.1 min, the EEG pattern had returned to the awake state (extremes 4.3 to 19 min).(ABSTRACT TRUNCATED AT 250 WORDS)     

Continuous propofol infusion versus enflurane in children operated on for strabismus. Comparison of the quality of anesthesia and recovery conditions

In children, the use of a continuous infusion of propofol has not yet been reported. A study was therefore designed to compare the characteristics of anaesthesia and recovery when either propofol or enflurance was used as the main anaesthetic agent. All 42 children (14 girls, 28 boys), ASA I and scheduled for corrective squint surgery under general anaesthesia, received 350 micrograms.kg-1 midazolam and 40 micrograms.kg-1 atropine intrarectally 20 min before induction, which was carried out with 3 mg.kg-1 propofol intravenously in 20 s. The patients were then randomly assigned to two groups, according to the drug used for maintenance: group P (n = 21) received a continuous intravenous infusion of propofol, 18 mg.kg-1.h-1 for the first 30 min and 15 mg.kg-1.h-1 thereafter; group E (n = 21) received 2.5%, then, after 30 min, 2% enflurane. Both groups were given 15 micrograms.kg-1 dextromoramide and 0.09 mg.kg-1 vecuronium. During anaesthesia, the following parameters were monitored: systolic (Pasys), diastolic (Padia) and mean arterial (Pa) pressures, heart rate (fc), the presence or not of an oculocardiac reflex with or without a 20% fall in fc which responded to 10-15 micrograms.kg-1 atropine, the appearance of a cardiac dysrhythmia, duration of anaesthesia and the delay before extubation. Recovery was assessed 1, 2, 4 and 6 h postoperatively by using both clinical and psychomotor criteria, the latter being adapted to children having one or both eyes occluded.(ABSTRACT TRUNCATED AT 250 WORDS)     

Total intravenous anesthesia for two patients complicated with myotonic dystrophy

Total intravenous anesthesia with propofol, fentanyl and ketamine (PFK) was given to two patients complicated with myotonic dystrophy. Case-1: A 42-year-old female underwent a hemithyroidectomy. Anesthesia was induced slowly with intravenous ketamine 20 mg and propofol 60 mg. Her tracheal intubation was performed smoothly without any muscle relaxants. Anesthesia was maintained with propofol infusion of 5 mg.kg-1.h-1, ketamine infusion of 0.3 mg.kg-1.h-1 and fentanyl 200 micrograms in total. She regained consciousness 20 minutes after the end of propofol infusion, and 15 minutes later, her trachea was extubated without any troubles. Case-2: A 41-year-old female underwent a removal of left parotid tumor. Anesthesia was induced slowly with ketamine 40 mg and propofol 100 mg intravenously. Anesthesia was maintained with propofol infusion of 5-10 mg.kg-1.h-1, ketamine infusion of 0.5 mg.kg-1.h-1 and fentanyl 350 micrograms in total. No muscle relaxant was used through the surgical procedure. Emergence from anesthesia was observed 10 minutes after the end of propofol infusion and her trachea was extubated. When a nasogastric tube was pulled out, her respiration stopped suddenly and she was intubated again only for two hours without any troubles. In both cases their serum CPK levels and rectal temperatures were very stable. PFK method would be a choice for patients with myotonic dystrophy.     

A new sedation technique with propofol during spinal anesthesia

We compared our new sedation technique with propofol during spinal anesthesia (Group B, n = 50) with a previously described method by Mackenzie et al. (Group A, n = 20). In Group A, propofol was started at a rate of 6 mg.kg-1.h-1 for 10 minutes, followed by continuous infusion at a rate of 4 mg.kg-1.h-1 till the end of surgery. In Group B, propofol 0.4 mg.kg-1 was administered by a bolus injection at the beginning. One-hundred and fifty minutes after the first injection, propofol 0.2 mg.kg-1 was added. The third dose of 0.1 mg.kg-1 of propofol was given 150 seconds after the second dose, followed by continuous infusion at a rate of 4 mg.kg-1.h-1 till the end of surgery. When adequate sedation was not obtained in Group B, propofol 0.1 mg.kg-1 was added by bolus fashion occasionally. In Group A, it took 9 min. 29 sec. to complete adequate sedation assessed by Mackenzie and Grant's sedation score. On the other hand, in Group B, it was 7 min. 27 sec. (P < 0.05 compared with Group A). There was neither excitation nor movement during sedation in Group B, while 5 patients experienced such events in Group A. The blood concentrations of propofol in Group B was 0.946 +/- 0.076 microgram.ml-1 and 0.693 +/- 0.136 microgram.ml-1 at 5 minutes and 10 minutes after the beginning of propofol, respectively. These values were significantly lower than those reported by Kugimiya. Our newly developed method for sedation with propofol during spinal anesthesia would be safer and more effective than that previously described by Mackenzie et al.