Tracheal intubation without muscle relaxant--a technique using sevoflurane vital capacity induction and alfentanil

This randomized controlled study examined intubating conditions and haemodynamic changes following sevoflurane nitrous oxide induction in four groups: three different doses of alfentanil compared with low-dose alfentanil and suxamethonium. All patients received atropine 0.3 mg i.v. before induction of anaesthesia with vital capacity breaths of sevoflurane 8% (more than 7% in the inspiratory gas) in 60% nitrous oxide and oxygen. Patients were allocated randomly to four groups of intravenous supplements: group SA20, alfentanil 20 microg x kg(-1); group SA25, alfentanil 25 microg x kg(-1); group SA30, alfentanil 30 microg x kg(-1); group SSA, alfentanil 10 microg x kg(-1) and suxamethonium 1 mg x kg(-1). Orotracheal intubation and assessment of intubating conditions was performed by one of the investigators who was blinded to the subject's group. Intubating conditions were satisfactory or excellent in 83%, 80%, 92% and 96% of patients in groups SA20, SA25, SA30 and SSA respectively. These differences were not statistically significant. The increase in heart rate associated with laryngoscopy and tracheal intubation was effectively attenuated in all groups. Mean arterial pressure decreased significantly and similarly after induction in all groups. Two minutes after intubation the mean arterial pressure was increased significantly (P<0.05) compared to the post-induction value in group SSA. The intubating conditions obtained with sevoflurane plus alfentanil 30 microg x kg(-1) were comparable to those provided by the sevoflurane, suxamethonium and alfentanil 10 microg x kg(-1) combination.     

The effect of topical lignocaine on intubating conditions after propofol-alfentanil induction

Background: Recent studies have found satisfactory conditions for intubation of the trachea without using muscle relaxants using an intravenous technique combining propofol and alfentanil. In this study we evaluate intubating conditions with this method and either lignocaine applied topically in the larynx and trachea or placebo.
Methods: Sixty adult patients of ASA class I were premedicated with diazepam 15–20 mg and randomly allocated to one of two groups. For induction of anaesthesia both groups were given propofol 2.5 mg/kg and alfentanil 30 μg/kg. One group received 4 ml of lignocaine 40 mg/ml (≤3 mg/kg) topically into the larynx and trachea (group L), the other group an equal amount of isotonic saline (group S) in a double-blind design. Intubation conditions were assessed as excellent, good, moderately good, poor or impossible, scored on the basis of jaw relaxation, ease of insertion of the tube and coughing on intubation.
Results: The total score for group L was significantly better than the score for group S ( P <0.0001) with significant differences with respect to ease of intubation and coughing after intubation.
Conclusions: Induction of anaesthesia with propofol 2.5 mg/kg and alfentanil 30 μg/kg combined with 4 ml of lignocaine-spray 40 mg/ml into the larynx and trachea offered consistent and satisfactory intubation conditions. We thus recommend this method for tracheal intubation, where the use of muscle relaxants is not indicated.     

瑞芬太尼复合异丙酚麻醉诱导对气管插管条件及血流动力学的影响

目的对比不使用肌松剂的情况下,瑞芬太尼或芬太尼复合异丙酚麻醉诱导后对气管插管条件及血流动力学的影响。方法60名病人分为2组,诱导后2rain行气管插管术。分别记录诱导前、诱导后lmin及插管后2min的平均动脉压（MAP）和心率（Ha）。插管条件由操作者给予评分。结果两组插管成功率均为100％。瑞芬太尼组插管条件满意率80％,芬太尼73％。两组诱导后MAP和HR值较基础值均下降（P〈0．05）。插管后两组间的MAP值差异有统计学意义（P（0．05）。结论瑞芬太尼复合异丙酚麻醉诱导取得了同芬太尼复合异丙酚麻醉诱导一样良好的插管条件,在抑制插管引起的心血管反应方面瑞芬太尼组优于芬太尼组。     

Propofol and remifentanil for intubation without muscle relaxant: the effect of the order of injection

BACKGROUND: Common practice in intubation without muscle relaxant is to inject the opioid drug prior to the hypnotic drug. Because remifentanil reaches adequate cerebral concentration more rapidly than does propofol, we tested the hypothesis that injection of remifentanil after propofol might lead to better intubating conditions. METHODS: Thirty ASA I-II patients scheduled for elective surgery and with no anticipated difficult intubation were enrolled in the study. Five minutes after midazolam 30 microg kg(-1), patients were randomized into two groups: group PR received propofol 2.5 mg kg(-1) followed by remifentanil 1 microg kg(-1), and group RP received remifentanil 1 microg kg(-1) followed by propofol 2.5 mg kg(-1). Intubating conditions were compared using a well-validated score, and continuous arterial pressure was recorded non-invasively. RESULTS: Compared with group RP, intubating conditions were significantly better in group PR. The mean arterial pressure decrease was more pronounced in group RP. CONCLUSIONS: We therefore conclude that in premedicated healthy patients with no anticipated risk of difficult intubation, intubating and haemodynamic conditions are better when remifentanil is injected after propofol.     

Tracheal intubating conditions after induction with sevoflurane 8% in children. A comparison with two intravenous techniques

We studied tracheal intubating conditions in 120 healthy children, aged 3-12 years, in a blinded, randomised clinical trial. Children were randomly allocated to one of three groups: group PS, propofol 3 mg.kg-1 and succinylcholine 1 mg.kg-1 (n = 40); group PA, propofol 3 mg.kg-1 and alfentanil 10 microg.kg-1 (n = 40); group SF, sevoflurane 8% in 60% nitrous oxide in oxygen for 3 min (n = 40). Tracheal intubating conditions were graded according to ease of laryngoscopy, position of vocal cords, coughing, jaw relaxation and movement of limbs. Overall intubating conditions were acceptable in 39 of 40 children in the propofol/succinylcholine group, 21 of 40 children in the propofol/alfentanil group and 35 of 40 children in the sevoflurane group. Children receiving propofol and succinylcholine or sevoflurane had better intubating conditions overall than those given propofol and alfentanil (p < 0.01). In conclusion, anaesthetic induction and tracheal intubation using sevoflurane 8% for 3 min is a satisfactory alternative to propofol with succinylcholine in children.     

The effect on intraocular pressure of endotracheal intubation or laryngeal mask use during TIVA without the use of muscle relaxants

BACKGROUND: Depolarizing and non-depolarizing muscle relaxants possess many untoward side effects. In most patients endotracheal intubation may be performed with a propofol and alfentanil combination. The purpose of this study was to compare the effect on intraocular pressure (IOP) and haemodynamics of endotracheal (ET) intubation or laryngeal mask (LMA) insertion during total intravenous anaesthesia (TIVA) without the use of muscle relaxants. METHODS: In a randomised study, 20 patients scheduled for elective orthopaedic surgery were assigned to two groups of 10 patients. Anaesthesia was induced with i.v. alfentanil 40 micrograms/kg and propofol 2.5 mg/kg. LMA insertion or ET intubation was achieved by the same anaesthesiologist. Airway score, insertion score, patient response and haemodynamics were recorded. IOP measurements were recorded before and after induction, 1 and 2 min after ET intubation or LMA insertion, and 1 and 2 min after extubation. RESULTS: Mean arterial pressure and heart rate after insertion of the airway management devices was significantly higher than induction values in the ET group (P < 0.05), while during 2-3 min no significant changes were observed in LMA group. In all patients following propofol and alfentanil induction, IOP was significantly lower than preinduction values (P < 0.001). IOP following extubation was significantly higher than preinduction values in the ET group, but not in the LMA group (P < 0.001). CONCLUSION: During TIVA without the use of muscle relaxants neither LMA insertion nor ET intubation increased the IOP, but ET extubation did.     

Haemodynamic effects of intravenous clonidine on propofol or thiopental induction

The study evaluated the effects of premedication with intravenous clonidine on thiopental or propofol requirements for induction and haemodynamic changes associated with both induction and endotracheal intubation. Clonidine administered intravenously before induction of anaesthesia reduced propofol or thiopental requirements. The association of clonidine and propofol caused, after injection of the induction drug, a decrease in mean arterial pressure which was significantly greater than with thiopental. Moreover, a major haemodynamic stability was registered before and after laryngoscopy in the clonidine-thiopental group. These findings might contraindicate the clonidine-propofol combination in patients with cardiovascular disease.     

The influence of induction technique on intubating conditions 1 min after rocuronium administration: a comparison of a propofol-ephedrine combination and propofol

We conducted a double blind, prospective, controlled trial comparing intubating conditions after induction with a propofol-ephedrine combination or propofol alone, followed by rocuronium. One hundred adult patients were randomly assigned to receive either propofol 2.5 mg x kg(-1) and ephedrine 15 mg in combination or propofol 2.5 mg x kg(-1) given over 30 s, followed by rocuronium 0.6 mg x kg(-1) given over 5 s. Tracheal intubation was performed 1 min later. Jaw relaxation, vocal cord position and diaphragmatic response were used to assess intubation conditions. Tracheal intubation was successful and acceptable in all patients. There was a significantly higher proportion of intubating conditions graded as 'excellent' in the propofol-ephedrine group (84%) than in the propofol group (32%) (p < 0.0001). Vocal cord position and response to intubation were significantly better in the propofol-ephedrine group, although jaw relaxation was similar. Mean arterial pressure was maintained at pre-induction levels in the propofol-ephedrine group. In conclusion, induction with propofol and ephedrine in combination provided significantly better intubating conditions than propofol alone, when followed by rocuronium.     

A comparison of blind and lightwand-guided tracheal intubation through the intubating laryngeal mask

We have tested the hypothesis that intubation success rates, haemodynamic changes, airway complications and postoperative pharyngolaryngeal morbidity differ between blind and lightwand-guided intubation through the intubating laryngeal mask airway. One hundred and twenty paralysed anasthetised adult patients (ASA I-II, no known or predicted difficult airways) were assigned in a random manner to one of two equal-sized groups. In the blind group, patients were intubated blindly through the intubating laryngeal mask airway. In the lightwand group, patients were intubated through the intubating laryngeal mask airway assisted by transillumination of the neck with a lightwand. A standard sequence of adjusting manoeuvres was followed if resistance occurred during intubation or if transillumination was incorrect. The number of adjusting manoeuvres, time to intubation, intubation success rates, haemodynamic changes (pre-induction, pre-intubation, postintubation), oesophageal intubation, mucosal trauma (blood detected), hypoxia (oxygen saturation < 95%) and postoperative pharyngolaryngeal morbidity (double-blinded) were documented. Overall intubation success was similar (blind, 93%; lightwand, 100%), but time to successful intubation was significantly shorter (67 vs. 46 s, p = 0. 027) and the number of adjusting manoeuvres was significantly fewer (p = 0.024) in the lightwand group. There were no significant differences in blood pressure or heart rate between the groups at any time. Oesophageal intubation occurred more frequently in the blind group (18 vs. 0%, p = 0.002). The incidence and severity of mucosal injury, sore throat and hoarseness were similar between the groups. We conclude that lightwand-guided intubation through the intubating laryngeal mask is superior to the blind technique.     

Propofol 2 mg/kg is superior to propofol 1 mg/kg for tracheal intubation in children during sevoflurane induction

Background: Propofol has been used to facilitate tracheal intubation within a short time of sevoflurane induction without a muscle relaxant in children. We compared as the primary outcome the incidence of excellent intubating conditions after 8% sevoflurane and propofol 1 or 2 mg/kg. Methods: One hundred and four patients (2–7 years) were randomly assigned to receive propofol 1 mg/kg in group SP1 (n=53) or propofol 2 mg/kg in group SP2 (n=51) after inhalation induction using sevoflurane 8% in oxygen. Forty‐five seconds after propofol and controlled ventilation, intubating conditions were assessed using a four‐point scoring system based on ease of laryngoscopy, vocal cords position, coughing, jaw relaxation and limb movement. Heart rate and systolic blood pressure were measured as baseline, after sevoflurane induction, propofol, intubation and at 2 and 5 min following intubation. Results: Three patients in group SP1 were excluded from analysis. Time from sevoflurane induction to intubation (248.9±71.3 s in group SP1 vs. 230.9±61.3 s in group SP2) and endtidal sevoflurane before intubation (5.6±1.6% in group SP1 vs. 5.2±1.5% in group SP2) did not differ between the two groups. The incidence of excellent intubating conditions was significantly higher in group SP2 compared with group SP1 [47/51 (92%) vs. 28/50 (56%)]. The incidence of acceptable intubating conditions was significantly higher in group SP2 compared with group SP1 [48/51 (94%) vs. 35/50 (70%)]. No hemodynamic difference was noted at any time point between the two groups. Conclusion: Propofol 2 mg/kg during 8% sevoflurane induction resulted in a higher proportion of excellent intubating conditions compared with propofol 1 mg/kg.     

The haemodynamic effects of bronchoscopy Comparison of propofol and thiopentone with and without alfentanil pretreatment

The haemodynamic response to bronchoscopy under general anaesthesia was investigated. Forty patients were allocated at random to receive either thiopentone or propofol; half the patients in each group received in addition 18 micrograms/kg of alfentanil one minute before induction of anaesthesia. The heart rate, noninvasive blood pressure and Holter ECG was monitored in all patients. Significant increases in heart rate (p less than 0.05), systolic and diastolic arterial pressures (p less than 0.01) occurred in the thiopentone only group, following bronchoscopy. Systolic and diastolic arterial pressure decreased in patients receiving thiopentone plus alfentanil, following induction of anaesthesia and laryngoscopy (p less than 0.05). No significant haemodynamic changes were seen in either of the groups which received propofol. ST segment changes on subsequent Holter analysis were seen in four patients, but there were no significant differences between the groups. Anaesthesia with propofol alone provides adequate haemodynamic stability for bronchoscopy and the addition is superfluous.     

Comparison of remifentanil with alfentanil or suxamethonium following propofol anaesthesia for tracheal intubation.

Sixty ASA physical status I and II, premedicated patients were administered propofol 2 mg x kg-1 and remifentanil 2 microg x kg-1 (group R), alfentanil 50 microg x kg-1 (group A) or suxamethonium 1 mg x kg-1 (group S) as a rapid bolus. One minute after study drug administration, tracheal intubation was performed. Intubation conditions were then scored. Excellent or good conditions were observed in only 35% in group R compared with groups S and A (100% and 85%, respectively; p < 0.001). The haemodynamic response to tracheal intubation was blunted in groups R and A compared with group S (p < 0.001). The mean heart rate in groups R and A was significantly lower than group S (p < 0.001). We conclude that remifentanil 2 microg x kg-1 given as a rapid bolus will not produce intubating conditions as good as those obtained with alfentanil 50 microg x kg-1 or suxamethonium 1 mg x kg-1 if administered after propofol 2 mg x kg-1.     

Tracheal intubation without the use of muscle relaxants: a technique using propofol and varying doses of alfentanil.

We have noted that tracheal intubation can be accomplished in many patients after induction of anesthesia with propofol and alfentanil without the simultaneous use of muscle relaxants. This study was designed to evaluate airway and intubating conditions after administration of propofol and alfentanil in 75 ASA physical status I or II outpatients with Mallampati class I airways undergoing various surgical procedures. The patients were randomly assigned to one of five groups for induction of anesthesia. All patients received midazolam 1 mg IV before induction of anesthesia. Group I patients (n = 15) received d-tubocurarine 3 mg, thiamylal 4 mg/kg, and succinylcholine 1 mg/kg IV. Groups II-V patients (n = 15 each) received alfentanil 30, 40, 50, or 60 micrograms/kg followed by propofol 2 mg/kg IV. No muscle relaxants were given to patients in groups II-V. Airway management was performed by one of the authors who was blinded as to the dose of alfentanil administered. After loss of consciousness, patients' lungs were ventilated via face mask, and the ease of ventilation was recorded. Jaw mobility was also assessed. Ninety seconds after administration of the propofol or thiamylal, laryngoscopy was performed and exposure of the glottis and position of the vocal cords were noted. Intubation of the trachea was performed and patient response was noted. Heart rate and arterial blood pressure were also recorded before induction of anesthesia, after induction, and then again after intubation of the trachea. The lungs of all patients were easily ventilated via mask, and the jaw was judged to be relaxed in all patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of intubating conditions after rocuronium and suxamethonium following "rapid-sequence induction" with thiopentone in elective cases

Background : Rocuronium (Org 9426) was shown to have the fastest onset of action of all currently available non-depolarizing neuromuscular blocking drugs and to provide intubating conditions similar to those of suxamethonium 60 to 90 s after administration. We compared the intubating conditions after rocuronium and suxamethonium following rapid-sequence induction of anaesthesia.
Methods : Fifty unpremedicated patients of ASA physical status I or II, scheduled for elective surgery were studied. Anaesthesia was induced with thiopentone 6 mg kg^-1 followed randomly by suxamethonium 1 mg kg^-1 or rocuronium 0.6 mg kg^-1 and, 45 s later, intubation was commenced. Muscle fasciculations, intubating conditions and intubation time, haemodynamic variables and oxygenation were assessed.
Results : Intubation time did not differ between suxamethonium (9.8±2.2 s) (mean±SD) and rocuronium (10.5±2.9 s), respectively. Intubating conditions were clinically acceptable (good or excellent) in all patients given suxamethonium and in 96% of the patients given rocuronium. However, the condition of the vocal cords was better (P<0.05) and diaphragmatic response to intubation was less pronounced with suxamethonium (P<0.05). Changes in heart rate and arterial blood pressure were similar in both groups.
Conclusion : The authors conclude that rocuronium is a suitable alternative to suxamethonium for rapid tracheal intubation even under unsupplemented thiopentone anaesthesia, at least in elective, otherwise healthy patients. Its use for rapid-sequence induction under emergency conditions, however, needs further investigation.     

ECG T-wave amplitude changes during thiopentone induction with or without alfentanil

The T-wave amplitude of ECG is thought to reflect the sympathetic tone of the heart but anaesthesia studies on this topic are rare. Haemodynamic and ECG T-wave amplitude changes were studied during induction of anaesthesia in 24 ASA I-II patients. Twelve patients were given alfentanil 30 μg kg^-1 at induction while physiologic saline was given to the rest (control). Thiopentone was then administered at the rate of 5 mg s^-1 until eyelash reflex disappeared. Vecuronium 0.1 mg kg^-1 was given thereafter. No anticholinergics were used. The lungs were ventilated with 40% oxygen in air. Haemodynamic parametres and T-wave amplitude were measured before induction, before intubation, 30 s, 3 min and 5 min after intubation. A significandy higher amount of thiopentone was needed to abolish the eyelash reflex in the control group than in the alfentanil group ( P <0.001). There were no changes in heart rate (HR) in the alfentanil group during the trial. Systolic and diastolic arterial pressures (SAP and DAP) were continuously below the preinduction levels in the alfentanil group. After baseline HR, SAP and DAP were significantly higher in the control group than in the alfentanil group at each data point. T-wave amplitude flattened significantly ( P <0.001) after intubation in the control group while no significant changes were seen in the alfentanil group. T-wave flattening correlated to the increases in HR ( P <0.01) and SAP ( P <0.01). Three control patients with flattened T-wave had a transient bigeminia period after intubation. It is concluded that ECG T-wave amplitude flattening was associated with pressure and heart rate response to laryngoscopy and intubation. Alfentanil blunted these responses and prevented T-wave changes after intubation.     

Tracheal intubation without the use of muscle relaxants: remifentanil or alfentanil in combination with propofol

BACKGROUND: Alfentanil-propofol combination provides adequate conditions for tracheal intubation without neuromuscular blocking drugs in most patients. Providing an option for intense opioid effect without compromising recovery after short operations, remifentanil might offer benefits over alfentanil, especially in ambulatory surgery. In this study intubating conditions after remifentanil-propofol were compared to those after alfentanil-propofol. METHODS: In a randomized, double-blind study 60 healthy patients were assigned to one of three groups (n=20). After intravenous atropine, remifentanil 3 or 4 microg kg(-1) (Rem3 or Rem4) or alfentanil 30 microg kg(-1) (Alf30) was injected over 30 s followed by propofol 2.5 mg kg(-1). Sixty seconds after the administration of propofol, laryngoscopy and intubation were attempted. Intubating conditions were assessed as excellent, good or poor on the basis of ease of ventilation, jaw relaxation, position of the vocal cords, and patient response to intubation and slow inflation of the endotracheal tube cuff. RESULTS: Overall conditions at intubation were significantly (P<0.05) better, and the frequency of excellent conditions was significantly (P<0.05) higher in the Rem4 group compared with the Alf30 group. Intubation was judged to be impossible in 20%, 25% or 5% of the patients in the Alf30, Rem3 or Rem4 groups, respectively. No patient manifested signs of opioid-induced muscular rigidity. In terms of arterial pressures or heart rate, there were no differences between the groups. CONCLUSION: The best method was the combination of remifentanil 4 microg kg(-1) and propofol 2.5 mg kg(-1). This provided satisfactory intubating conditions in 93%, and prevented cardiovascular intubation response.     

A combination of alfentanil-lidocaine-propofol provides better intubating conditions than fentanyl-lidocaine-propofol in the absence of muscle relaxants

PURPOSE: To compare the ease of tracheal intubation without the use of muscle relaxants following an alfentanil-lidocaine-propofol sequence vs a fentanyl-lidocaine-propofol sequence. CLINICAL FEATURES: In 80 ASA I and II adult patients undergoing elective laparoscopic surgery, we compared the intubating conditions following alfentanil 20 microg x kg(-1), lidocaine 1.5 mg x kg(-1), propofol 3 mg x kg(-1) (Group I; n = 40) vs fentanyl 2 microg x kg(-1), lidocaine 1.5 mg x kg(-1), propofol 3 mg x kg(-1) (Group II; n = 40). The intubating conditions were scored by jaw relaxation, vocal cord position and response to intubation, as well as by blood pressure and heart rate changes. The intubating conditions were good or excellent in 95% of patients in Group I vs 62.5% of patients in Group II (P < 0.05). Blood pressure decreased from a preinduction value of 86 +/- 13 mmHg to 72 +/- 28 mmHg and 74 +/- 19 mmHg in Group I, and from 85 +/- 12 mmHg to 78 +/- 15 mmHg and 78 +/- 12 mmHg in Group II, one and five minutes following intubation (P < 0.05). This drop in blood pressure was not different between the two groups. CONCLUSION: An alfentanil-lidocaine-propofol sequence offers significantly better intubating conditions than a fentanyl-lidocaine-propofol sequence in healthy adult patients.     

Intubating conditions and haemodynamic changes following thiopentone or propofol for early tracheal intubation

Intubating conditions and haemodynamic changes were studied 30 sec after a fixed induction dose of thiopentone or propofol in patients scheduled for elective surgery. The hypnotic agent was preceded by the administration of papaveretum 10 mg three minutes before induction and alcuronium 0.2 mg·kg^?1 at induction. Ease of intubation was graded and the study conducted in a randomised double-blind fashion. In the thiopentone group (n=30) intubation was very easy in 73% compared with 79% in the propofol group (n=29). In two patients in the propofol group the tracheas were moderately difficult to intubate but there were no failed intubations in either group. No patients recalled the intubation period on subsequent postoperative questioning. The immediate post-induction average systolic pressure in the thiopentone group decreased by 0.7% (range 15.9% increase to 25.3% decrease) whilst the post-intubation systolic pressure increased by 6.3% (range ?31.5% increase to 24.2% decrease). In the propofol group there was a decrease in systolic pressure after induction (average 14.4%; range 15.5% increase to 41.4% decrease, P < 0.05) but the subsequent pressor response to intubation was markedly attenuated compared with baseline (average systolic pressure decreased 15.5% (range 22.4% increase to 42.7% decrease)). Following intubation and maintenance, ventilation with nitrous oxide 70% and halothane 1% the systolic pressure decreased markedly in both groups with a greater reduction in the propofol group (P < 0.05). Compared with baseline there were increases (P < 0.0001) in heart rate in both groups from induction of anaesthesia to the end of study. The results show that early tracheal intubation can be undertaken following thiopentone and is accompanied by haemodynamic stability. Comparable intubating conditions are associated with propofol but the dose used resulted in a considerable decrease in systolic blood pressure after induction.     

Induction characteristics of thiopentone/suxamethonium, propofol/alfentanil or halothane alone in children aged 1-3 years.

The aim of this study was to compare the effect of three different induction techniques, with or without neuromuscular block, on tracheal intubation, haemodynamic responses and cardiac rhythm. Ninety children, aged 1-3 years, undergoing day-case adenoidectomy were randomly allocated to three groups: group TS received thiopentone 5 mg kg-1 and suxamethonium 1.5 mg kg-1, group H 5 Vol.% halothane and group PA alfentanil 10 micrograms kg-1 and propofol 3 mg kg-1 for induction of anaesthesia. No anti-cholinergics were used. Holter-monitoring of the heart rate and rhythm was started at least 15 min before induction of anaesthesia and continued until 3 min after intubation. Tracheal intubation was performed by an anaesthetist blinded to the induction method and judged as excellent, moderate or poor according to ease of laryngoscopy, position of vocal cords and incidence of coughing after intubation. Tracheal intubation was successful at the first attempt in all children in groups TS and H and but only in 80% in group PA (P = 0.001). Intubating conditions were excellent in 22 (73%), 22 (73%) and one (3%) of the patients in groups TS, H and PA, respectively (P = 0.001). Cardiac dysrhythmias (supraventricular extrasystole or junctional rhythm) occurred in two (7%) patients in groups PA and H each (NS). Bradycardia occurred in 0 (0%), four (14%) and six (21%) children in groups TS, H and PA, respectively (P = 0.007 PA vs. TS, P = 0.03 H vs. TS). In conclusion, induction of anaesthesia with propofol 3 mg kg-1 and alfentanil 10 micrograms kg-1 without neuromuscular block did not provide acceptable intubating conditions in children 1-3 years, although it preserved arterial pressure better than thiopentone/suxamethonium or halothane. Cardiac dysrhythmias were few regardless of the induction method.     

Randomized comparison of outcome after propofol-nitrous oxide or enflurane-nitrous oxide anaesthesia in operations of long duration

A randomized, prospective, comparative study was performed to evaluate induction characteristics, haemodynamic changes and recovery in 60 ASA I-II patients undergoing mainly gynaecological laparotomies with either propofol or thiopentone-enflurane anaesthesia. The propofol group (n = 30) received 2 mg.kg-1 propofol for induction of anaesthesia followed by propofol infusion. The thiopentone-enflurane group (n = 30) received thiopentone 4 mg.kg-1 for induction followed by enflurane (0.5-2 per cent). All patients received nitrous oxide (66 per cent] in oxygen begun one minute after tracheal intubation, and fentanyl (1.5 micrograms.kg-1) four minutes prior to induction. Other drugs administered during or after anaesthesia were similar among the groups. Haemodynamic measurements were similar between propofol and enflurane groups except after tracheal intubation when the mean arterial pressure was lower in the propofol group (P less than 0.05). The propofol group had significantly less (P less than 0.01) emesis in the recovery room than the enflurane group. The propofol group experienced significantly less (P less than 0.05) dizziness, depression/sadness and hunger than the enflurane group in the postoperative period as assessed with a visual analogue questionnaire. We conclude that propofol provided better outcome than enflurane in terms of these nonvital but annoying outcome measures after relatively long intra-abdominal operations.