The electrocardiographic and hemodynamic effect of metohexital and propofol with and without esmolol.

BACKGROUND: Metohexital and propofol are short-acting induction agents, which have a tendency to prolong the QTc interval of the ECG. We studied whether this increase could be prevented by combining a beta-blocking agent, esmolol, with these drugs. Simultaneously, we studied the hemodynamic effects of these combinations. METHODS: In a randomized, double-blind study, 80 ASA I-II young adults were premedicated with oxycodone and atropin and allocated to one of four groups: propofol (P), propofol + esmolol (P + E), metohexital (E) or metohexital + esmolol (M + E). The doses were 2 mg/kg propofol/metohexital and 1 mg/kg esmolol. Alfentanil 15 microg/kg was used in all groups. The hemodynamic parameters were measured non-invasively and the electrocardiographic parameters using the signal processing method. RESULT: The highest QTc values, which often exceeded the normal upper limit of 440 ms, were recorded at the baseline or immediately after the administration of the induction drugs. The intervals were significantly shorter if esmolol was co-administered with either propofol or metohexital. The heart rate increased in the group M and decreased in the group P + E but remained unchanged in the groups P and M + E. Systolic and diastolic arterial pressures decreased during the study in all groups, most prominently in group P + E. CONCLUSIONS: During the anesthesia induction, the QTc interval was significantly shorter when esmolol was co-administered with either propofol or metohexital. The hemodynamic responses were properly controlled with the combination of metohexital and esmolol as well as with propofol alone, but the combination of propofol and esmolol tended to cause hemodynamic depression.

Practice-based criteria for assessing anaesthetists' habits of action: outline for a reflexive turn in practice.

BACKGROUND: From an ecological perspective, we have demonstrated two distinct logics of practice in anaesthesia. One reflected attitudes characteristic of traditional medical thinking, while the other an insight into the uncertainty of actual situations. OBJECTIVE: We explored interactions between anaesthetists and patients, i.e. anaesthetist's habit of action. By tools we mean information, drugs, and concepts. METHODS: For studying the expert anaesthetists' habits of action in clinical circumstances, wide-ranging material was necessary including video recordings, documented observations and interviews. For each anaesthesia, characteristic cycles between perceived information and regulative actions were constructed. Together with meanings of distinct actions, they constituted the material for analysis of the criteria for evaluation. RESULTS: Besides differentiating the two habits of action, the criteria might provide a perspective for assessing trainees' performances. The 'reactive' habit of action was qualified by conservative and monological ways of using tools and reluctance to construct subjective evaluations. A failure to recognise the semantic aspect of information contributed to the absence of learning. The 'interpretative' habit of action, however, was qualified by creative and interactive use of tools. Ongoing sense-making and anticipation were achieved through cumulative learning based on a dialogical and reflective way of constructing subjective interpretations. CONCLUSION: Professional behaviour was defined through selectivity, interpretation, and judgement. To argue for a professional artistry view is to argue for how we should use our conceptual and material tools in striving for excellence.

Gastric air tonometry during laparoscopic cholecystectomy: a comparison of two PaCO2 levels.

PURPOSE: Pneumoperitoneum can cause disturbances in acid-base balance and splanchnic perfusion. We studied the effect of ventilation on acid-base balance and gastric mucosal tonometric values in patients undergoing laparoscopic cholecystectomy. METHODS: Twenty-four patients (ASA I-II) were randomly allocated into two groups. In the fixed ventilation group, ventilation was constant allowing free increase in PCO2, while in the constant CO2 group end-tidal PCO2 was fixed with ventilatory adjustment. Intraabdominal pressure was limited to 12 mmHg. Arterial acid-base balance, automated air tonometric variables and gastric mucosal to arterial PCO2 gap were determined frequently from anesthesia induction until three hours postoperatively. RESULTS: During pneumoperitoneum, in the fixed ventilation group arterial PCO2 changed from 5.0 +/- 0.2 to 6.6 +/- 0.4 kPa and pH from 7.43 +/- 0.03 to 7.33 +/- 0.04, tonometric PCO2 from 5.1 +/- 0.5 to 6.9 +/- 0.4 and pH from 7.44 +/- 0.04 to 7.33 +/- 0.04. In the constant CO2 group these variables remained at control levels (P < 0.01 between groups). The PCO2 gap remained unchanged without any differences between the groups. In the recovery room all measured variables were within normal range in both groups. CONCLUSION: Despite inter-group differences in arterial and tonometric PCO2 and pH values during CO2 pneumoperitoneum, the patients did not develop splanchnic hypoperfusion detectable by air tonometric method, as indicated by normal PCO2 gap in both groups throughout the study.

Tracheal intubation after induction of anesthesia in children with propofol--remifentanil or propofol-rocuronium.

PURPOSE: To compare the intubating conditions after remifentanil-propofol with those after propofol-rocuronium combination with the aim of determining the optimal dose of remifentanil. METHODS: In a randomized, double-blind study 80 healthy children aged three to nine years were assigned to one of four groups (n=20): 2 or 4 microgxkg(-1) remifentanil (Re2 or Re4); 2 microgxkg(-1) remifentanil and 0.2 mgxkg(-1) rocuronium (Re2-Ro0.2); 0.4 mgxkg(-1) rocuronium (Ro0.4). After atropine, remifentanil was injected over 30 sec followed by 3.5 mgxkg(-1) propofol and rocuronium. After 60 sec, laryngoscopy and intubation were attempted. Intubating conditions were assessed as excellent, good or poor based on ease of ventilation, jaw relaxation, position of the vocal cords, and coughing to intubation. RESULTS: In all children intubation was successful. Overall intubating conditions were better (P < 0.01), and the frequency of excellent conditions, 85%, was higher (P < 0.01) in the Re4 group than in the Ro0.4 group. No child manifested signs of muscular rigidity. In the remifentanil groups, arterial pressure decreased 11-13% and heart rate 6-9% after anesthetic induction, and remained at that level throughout the study. CONCLUSION: The best intubating conditions were produced by the combination of 4 microgxkg(-1) remifentanil and 3.5 mgxkg(-1) propofol. It provided excellent or good intubating conditions in all children without causing undue cardiovascular depression.

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.

Methodological considerations in analysing anaesthetists' habits of action in clinical situations.

Human activity can be seen as an intentional, context-dependent enterprise explained through meanings the actors attach to their activity and their directly observable interactions with the environment. The authors have demonstrated previously a new conceptual framework to describe the anaesthetist's activity. One of the central concepts besides orientation is habit of action referring to the way in which the actor has organized his actions when interacting with his environment, in this case a patient with unique physiological potentials, information monitors and anaesthetic drugs. The activity dependent on contingent, particular circumstances, needs to be studied as it appears in a natural situation. Using an idiographic study design the authors have examined the activity of eight expert anaesthetists in clinical settings to determine the characteristics of their habits of action. To capture the fleeting circumstances during the anaesthetic process, a wide observational basis was necessary. It consisted of videotapes, detailed expert observations, and interviews. The conceptual analysis of the subject, habit of action, is described step-by-step. Two distinct habits of action could be identified, confirming earlier results. The interpretative habit of action was characterized by extensive use of situational information in order to construct a cumulative conception of the patient's physiological potentials to control the process accurately. Moreover, rich dialogue between formal professional knowledge and patient-specific, particular knowledge was evident. The reactive habit of action was characterized by a tendency to regulate the process by means of predetermined conventional ranges of measured patient parameters shown by monitors. The authors discuss their methodological solutions and results, and explicate their differences to the earlier approaches.

Analysis of the clinical behaviour of anaesthetists: recognition of uncertainty as a basis for practice.

The dynamic complexity of anaesthesia sets specific requirements for the activity of anaesthetists. By exploring the significance given by anaesthetists to their work we have demonstrated a new conceptual framework and confirmed our hypothesis that there are differences in the orientations of anaesthetists, and that these become manifest in different types of clinical behaviour. We describe methods the anaesthetists use in framing the focus of their work, the patient in anaesthesia. The patient's uniqueness and uncertainty in anaesthesia were recognized in the 'realistic' orientation, which is characterized by an extensive use of situational information and an aim to construct a cumulative interpretation of a patient's physiological state. In the objectivistic orientation the patient was treated as a natural object and uncertainty was not recognized. This orientation is typified by a reactive habit of action which seemed to be based on a preoperative plan, and its deterministic implementation. Our results point to the need for a new strategy to cope with the uniqueness and uncertainty of actual problems. This has implications for education and practice in anaesthetic practice, since uncertainty is increasing with the ageing patient population and with implementation of new technology.

Effect of transdermal hyoscine on nausea and vomiting after surgical correction of prominent ears under general anaesthesia.

In a double-blind, randomized study, we have compared the efficacy of transdermal hyoscine with placebo in the reduction of nausea and vomiting in 50 patients, ASA I-II, after surgical correction of prominent ears under general anaesthesia. In the placebo group, 28%, 4% and 48% of patients suffered nausea, retching and vomiting, respectively, during the first 24 h after anaesthesia. The corresponding values in the hyoscine group were 12%, 0% and 16% (P < 0.01). In the placebo group more patients (48%) needed droperidol as an antiemetic compared with the hyoscine group (16%; P < 0.05). There was significantly more sedation in the hyoscine group.

Prevention of nausea and vomiting with transdermal hyoscine in adults after middle ear surgery during general anaesthesia.

In a double-blind, randomized study, we have compared the efficacy of transdermal hyoscine in the prevention of nausea and vomiting with placebo in 60 young, ASA I-II patients after middle ear surgery during general anaesthesia. In the placebo group, 27% and 43% of patients suffered from nausea and vomiting, respectively, during the first 24 h after anaesthesia. The corresponding values for both symptoms in the hyoscine group were 10% (P < 0.001 between groups). The frequency of side effects was similar in both groups. The results suggest that transdermal hyoscine is a useful prophylaxis against nausea and vomiting after middle ear surgery.

Tracheal intubation after induction of anaesthesia with propofol, alfentanil and lidocaine without neuromuscular blocking drugs in children.

In a double-blind study, intubating conditions and haemodynamic responses were assessed in two age-groups of 45 ASA I-II children, with mean ages of 2.4 and 6.3 years, premedicated with oral midazolam and atropine. The children were randomly allocated to one of three groups: alfentanil 20 micrograms.kg-1 + lidocaine 1 mg.kg-1 (Alf20 + Lign); alfentanil 20 micrograms.kg-1 (Alf20); or alfentanil 40 micrograms.kg-1 (Alf40), followed by propofol 3.5 mg.kg-1 in the children aged 1-3 years and 3.0 mg.kg-1 in the older children. Intubating conditions, 40 s after the administration of propofol, were assessed as good, moderate or impossible on the basis of jaw relaxation, ease of insertion of the endotracheal tube and coughing during intubation. In the younger age group the frequencies of good, moderate or impossible intubating conditions were 87, 13 and 0% in the Alf40, 40, 60 and 0% in the Alf20 (P < 0.05 compared to the Alf40 group) and 53, 47 and 0% in the Alf20 + Lign group. In the older age group the corresponding frequencies were 60, 33 and 7% in the Alf20 + Lign, 47, 53 and 0% in the Alf20 and 47, 40 and 13% in the Alf40 group. All the drugs prevented any increase in arterial pressure and heart rate after tracheal intubation. The QTc interval of the ECG was always in the normal range. Clinically important bradycardia did not occur. In conclusion, the best intubating conditions occurred after propofol 3.5 mg.kg-1 and alfentanil 40 micrograms.kg-1 in the younger age group.(ABSTRACT TRUNCATED AT 250 WORDS)

Haemodynamic responses and prolongation of QT interval of ECG after suxamethonium-facilitated intubation during anaesthetic induction in children: a dose-related attenuation by alfentanil.

The haemodynamic response to endotracheal intubation and changes in the QT interval of ECG during anaesthetic induction were studied in 68 healthy children (5.5 years). The children were pretreated double-blindly with either alfentanil 10 micrograms/kg (A10), 25 micrograms/kg (A25), 50 micrograms/kg (A50) or saline (control) (17 children in each group) i.v. 1 min before thiopentone 5 mg/kg. The trachea was intubated after suxamethonium 1.5 mg/kg. Central nervous system excitation was seen in four of 17 and in one of 17 children after alfentanil 50 and 25 micrograms/kg, respectively. After intubation, heart rate increased significantly in the control group, remained at initial levels in the A10 and A25 groups and decreased in the A50 group. A pressor response to intubation was seen in the control and A10 groups. The QT interval was significantly prolonged after suxamethonium in the control and A10 groups, but remained at baseline levels in the A25 and A50 groups. Ventricular ectopic beats were only seen in 2/17 children in the control group. In conclusion, alfentanil 25 microgram/kg is ideal for preventing the haemodynamic response to endotracheal intubation and prolongation of the QT interval, a sign of sympathoadrenal activation, before induction of intravenous anaesthesia in children.

Injection pain, intubating conditions and cardiovascular changes following induction of anaesthesia with propofol alone or in combination with alfentanil.

In a double-blind study, propofol (P) 2-2.5 mg.kg-1 preceded by saline (Sal) or alfentanil (A) 20-30 micrograms.kg-1 was used for anaesthetic induction in 59 young patients of ASA physical class I or II, premedicated with oxycodone 0.1 mg.kg-1 and atropine 0.01 mg.kg-1 i.m. The patients were randomly allocated to one of the four groups: Group 1 Sal + P2.5, Group 2 A20 + P2.5, Group 3 A30 + P2.5 and Group 4 A30 + P2. Pain on injection of propofol occurred in 67, 36 and 7% of the patients in the Sal + P2.5, A20 + P2.5 and A30 + P2 groups, respectively, but not at all in the A30 + P2.5 group. Intubating conditions were assessed as good, moderate, poor or impossible on the basis of jaw relaxation, ease of insertion of the tube and coughing on intubation, each on a three-point scale. In impossible cases, suxamethonium was used. In the Sal + P2.5 group, the frequencies of good, moderate, poor and impossible intubating conditions were 0, 38, 8 and 54%, respectively. The corresponding figures in the A30 + P2.5 group were 43, 46, 7 and 14% (P less than 0.05 between the groups). The other groups did not differ significantly from the Sal + P2.5 group. After injection of propofol, both systolic and diastolic arterial pressures decreased significantly in all other groups, with the exception of diastolic pressure in the Sal + P2.5 group, whereas heart rate did not differ from the control level. After intubation, systolic arterial pressure increased statistically significantly in the Sal + P2.5 and A30 + P2 groups and diastolic arterial pressure in all other groups with the exception of the A30 + P2.5 group when compared with the corresponding preceding values.(ABSTRACT TRUNCATED AT 250 WORDS)

QT interval of the ECG, heart rate and arterial pressure using propofol, methohexital or midazolam for induction of anaesthesia.

The effects of propofol 2 mg/kg, methohexital 2 mg/kg or midazolam 0.3 mg/kg were studied on the QT interval of the ECG corrected by the heart rate (QTc), heart rate and arterial pressure during induction of anaesthesia in 87 ASA class I-(II)-patients. The patients were randomly allocated to one of the three anaesthetic groups. The incidence of the patients with a prolonged QTc interval (= more than 440 ms) ranged from 29 to 41% between the groups. In each group these patients were treated separately. After all anaesthetics, the QTc interval was significantly prolonged in the patients with a normal control QTc interval, whereas in the patients with a prolonged control QTc interval, it tended to be shortened both after propofol and methohexital and it was significantly shortened after midazolam. After injection of suxamethonium, no significant QTc interval changes occurred in the patients with a normal control QTc interval in either the propofol or the methohexital groups, whereas in the patients with a prolonged control QTc interval treated with propofol the QTc interval decreased significantly 60 s after suxamethonium when compared with the corresponding preceding values. The mean values in the propofol group in the patients with a normal control QTc interval were always below the upper limit of the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)

Post-operative sore throat: effect of lignocaine jelly and spray with endotracheal intubation.

The effects of laryngeal lignocaine spray and/or lignocaine jelly as lubricants were studied on the incidence of sore throat, hoarseness, or tracheal irritability as evidenced by either a tendency to cough or frank coughing after intubation with a Sensiv tube (Searle Medical Products). Pressure in the medium-volume, low-pressure cuff was controlled and kept below 2.5 kPa (25 cmH2O) during anaesthesia. The side-effects of 94 surgical patients were recorded in a double-blind manner in the recovery room and on the first post-operative day. The lowest number of patients (62%) with side-effects was found in the control group and the greatest (95%) after the combination of lignocaine jelly and spray (P less than 0.05). The number of side-effects after lignocaine jelly alone was 85% and after the spray alone 68%. Women were more prone to have side-effects, especially sore throat and hoarseness, than men (P less than 0.05). Induced hypotension did not increase the incidence of side-effects. Endotracheal cuff pressures were also studied in 114 patients during N2O-O2 anaesthesia and in 54 patients after the replacement of N2O with nitrogen. The minimum occluding pressure required was 1 kPa (10 cmH2O). In 42% of the patients receiving N2O a limiting value of 2.5 kPa (25 cmH2O) was reached during anesthesia in a mean time of 74 min (range 25-180 min). After the replacement of N2O with nitrogen, the cuff pressure decreased from 1.8 kPa (18 cmH2O) to 0.7 kPa (7 cmH2O) over 40 min. It is concluded that lignocaine jelly with the use of a spray significantly increases post-operative side-effects.

QT interval of the ECG, heart rate and arterial pressure using five non-depolarizing muscle relaxants for intubation.

The QT interval, heart rate and arterial pressure were measured during anaesthetic induction in 186 patients without cardiovascular diseases or any preoperative drugs. The study was randomized and double-blind. The patients were premedicated with either pethidine 1 mg/kg + atropine 0.01 mg/kg or with only pethidine 1 mg/kg i.m. Anaesthesia was induced with thiopental. After both types of premedication, either d-tubocurarine 0.5 mg/kg, alcuronium 0.3 mg/kg, pancuronium 0.1 mg/kg, vecuronium 0.1 mg/kg or atracurium 0.5 mg/kg was injected after thiopental. Laryngoscopy was performed 4 min after the relaxant. The control values of the QT intervals (mean value 433 ms, range of the mean values 422-453 ms), were comparable. After thiopental, the mean values in the groups were no longer in the normal range (less than 440 ms). After atropine, the values at 3 min were statistically significantly prolonged in the pancuronium, atracurium and alcuronium groups, but not in the other groups, when compared with the values after thiopental. In the absence of atropine, no statistically significant prolongation of the QT interval occurred. After intubation in the absence of atropine, the values were statistically significantly prolonged in the alcuronium, pancuronium, vecuronium and atracurium groups and in the presence of atropine in the atracurium group when compared with the preceding values. The QT intervals were prolonged only in relation to the increased heart rate. At 6.5 min, the values in all groups were decreased to about the same level as before intubation. The mean control values of the heart rate were between 80 and 90 b.p.m. in the atropine-treated groups and between 70 and 80 b.p.m. in the other groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of chloral hydrate and midazolam by mouth as premedicants in children undergoing otolaryngological surgery.

Chloral hydrate 25, 50 or 75 mg kg-1 or midazolam 0.4, 0.5 or 0.6 mg kg-1, all given by mouth in combination with atropine 0.03 mg kg-1, were compared as premedication in 248 children in a randomized, double-blind study. Chloral hydrate was significantly less palatable than midazolam. The anxiolytic effect of chloral hydrate 75 mg kg-1 was "good" in children younger than 5 yr, whereas the other doses of chloral hydrate, and all doses of midazolam, provided only "fair" anxiolysis in this age group. All doses of both premedicants provided good anxiolysis in the older children. A satisfactory antisialogogue effect was seen in 83-90% of each group. About 20 min after extubation, restlessness was observed in 15-25% of the younger children premedicated with chloral hydrate 25 mg kg-1 or with midazolam 0.4 or 0.6 mg kg-1. The mean total recovery score (0-10) based on activity, ventilation, heart rate, conscious level and colour ranged between 5.8 and 6.8 at 10 min and between 9 and 9.5 at 70 min after extubation in all groups. Midazolam 0.5 mg kg-1 is recommended for children less than 5 yr of age and midazolam 0.4-0.5 mg kg-1 for older ones. Chloral hydrate 75 mg kg-1 provided good anxiolysis in both age groups; however, it was less palatable than the midazolam.

Optimal time interval between pretreatment with alcuronium and suxamethonium during anaesthetic induction.

Alcuronium 0.03 mg/kg was studied in a double-blind randomized fashion as a pretreatment before suxamethonium using different time intervals between the administration of the drugs in 78 patients (ASA I-II) undergoing otolaryngological surgery. Alcuronium was given 1, 2 or 3 min before suxamethonium 1.5 mg/kg. The control group received saline as a pretreatment and suxamethonium 1 mg/kg. Anaesthesia was induced with thiopental 5.5 mg/kg over 60 s. Muscle fasciculations, intubating conditions, cardiovascular responses to endotracheal intubation and duration of neuromuscular block were assessed. Muscle fasciculations were statistically and similarly inhibited (P less than 0.01) at all time intervals between alcuronium and suxamethonium. Intubating conditions were worse (P less than 0.05) in the 3-min group than in the other groups. Cardiovascular responses to endotracheal intubation were similar in all groups. The neuromuscular block after suxamethonium was significantly shorter (P less than 0.05) in the 2- and 3-min groups than in the other groups. In conclusion, from the clinical point of view the 1-min time interval between alcuronium and suxamethonium is optimal since muscle fasciculations are inhibited and intubating conditions are satisfactory.

Protection by fentanyl against cardiac dysrhythmias during induction of anaesthesia.

The effect of fentanyl on electrocardiographic changes during anaesthetic induction was studied in 113 adults and 77 children. The adults were pretreated with fentanyl 1, 2 or 3 micrograms kg-1 and the children received fentanyl 1 or 2 micrograms kg-1 as pretreatment. The control groups received no pretreatment. Two minutes after the pretreatment, thiopentone 5 mg kg-1 was injected followed by succinylcholine 1.5 mg kg-1 before laryngoscopy and intubation. In control adults, ventricular ectopic beats (VEB) occurred in 26% of the patients whereas fentanyl in all doses totally prevented them. In children, the incidence of VEB was 22% in the control group whereas both doses of fentanyl prevented the occurrence of VEB. In any doses, fentanyl did not prevent the prolongation of QT interval after succinylcholine.

Labetalol as a hypotensive agent for middle ear microsurgery.

Labetalol, an alpha- and beta-adrenergic receptor-blocking agent, was studied as a hypotensive agent during halothane (mostly 0.5 vol.%)-N2O-fentanyl-d-tubocurarine anaesthesia with a head-up tilt of 5 degrees in 41 patients undergoing middle ear microsurgery. After the mean initial dose of 0.3 mg/kg, the mean need for labetalol ranged from 0.05 to 0.07 mg/kg at 30 +/- 5-min intervals. The mean duration of the hypotensive period was 102 min. During the hypotension, the average mean arterial pressure ranged from 59 to 62 mmHg (7.9-8.3 kPa) and the mean heart rate from 61 to 66 b.p.m. After labetalol the maximum cardiac output decrease was 7%. Before labetalol the mean PaO2 value was 158 mmHg (21.1 kPa) and during hypotension it ranged from 145 to 149 mmHg (19.3-19.9 kPa) when FiO2 was 40%. The only peroperative side effects were ECG changes (middle junctional rhythm and sinus bradycardia) which occurred in 10% of the patients. The mean value for the degree of haemostasis rated by the otologist on a visual analogue scale between poor (0 mm) and excellent (100 mm) was 91 mm. The patients were able to open their eyes and to give their names 8-9 min after the end of anaesthesia. After extubation the patients were normotensive and there were no clinically significant changes in the cardiovascular parameters during the 4-h recovery room period. Acid-base status showed slight metabolic acidosis. The most common postoperative side effects were nausea only and nausea + vomiting, which occurred in 39% and 20% of the patients, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)