Biomedical subjects

L Saarnivaara

Publications and source records attributed to L Saarnivaara.

At least 19 recordsLinked to original sources

PubMed1992

Injection pain, cardiovascular changes and recovery following induction of anaesthesia with propofol in combination with alfentanil or lignocaine in children.

The effect of pretreatment with alfentanil 10 (Alf10), 15 (Alf15) or 20 (Alf20) micrograms.kg-1 on reducing injection pain caused by propofol was compared with lignocaine 10 mg mixed with propofol (Lign). This double-blind, double-dummy and randomized study included 100 children with a mean age of 4.3 +/- 0.6 years, 25 children in each group, undergoing minor otolaryngological surgery. The children were premedicated orally with midazolam 0.5 mg.kg-1 and atropine 0.03 mg.kg-1. Injection pain occurred in 4% in the Lign group. The corresponding figures were 40, 16 and 20% in the Alf10, Alf15 and Alf20 groups, respectively. Both 1% lignocaine 10 mg and alfentanil 15 micrograms.kg-1 reduced injection pain significantly compared with alfentanil 10 micrograms.kg-1. Pretreatment with alfentanil significantly diminished haemodynamic responses to tracheal intubation. Furthermore, the concomitant use of alfentanil and propofol caused transient severe bradycardia and a significant decrease in heart rate after laryngoscopy.

Alfentanil↗

PubMed1992

[Interactions between lithium/rubidium and six muscle relaxants. A study on the rat phrenic nerve-hemidiaphragm preparation].

The cumulative concentration-response curves for alcuronium, metocurine, d-tubocurarine, suxamethonium, pancuronium and vecuronium alone or in combination with lithium or rubidium were measured using indirectly evoked twitch tension in the isolated rat phrenic nerve-hemidiaphragm preparation. In the experiments with lithium and rubidium, 10% and 2% of the sodium ions (118 mmol/l) of Krebs solution were replaced by lithium (11.8 mmol/l = 0.082 g/l) or rubidium (2.36 mmol/l = 0.202 g/l) ions, respectively. At these concentrations, neither lithium nor rubidium alone affected twitch tension. Lithium led to a statistically significant enhancement of the myoneural blocking effects of suxamethonium, pancuronium and vecuronium, but not of the other myoneural blocking drugs. Rubidium behaved similarly to lithium, except that enhancement of the effect of vecuronium was not statistically significant. At higher concentrations, lithium and rubidium alone depressed twitch tension in a dose-dependent manner. Neither myoneural blocking drugs nor lithium and rubidium affected the directly evoked twitch tension. It is concluded that myoneural blocking drugs, especially the newer ones, should be used with caution in patients receiving lithium or other alkali metal therapy as it is not known what interactions may arise.

Animals↗

PubMed1991

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)

Adult↗

PubMed1991

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.

Alfentanil↗

PubMed1991

Oral atropine enhances the risk for acid aspiration in children.

Two modes of administration of an anticholinergic drug were compared in 58 healthy children undergoing adenoidectomy. The study was double-blind and randomized. All children were premedicated with oral midazolam 0.5 mg/kg. Twenty-nine children received oral atropine 0.03 mg/kg (Group A) and the rest were given i.v. glycopyrrolate 0.005 mg/kg at the induction of anaesthesia (Group G). In Group A, of 29 children, the stomach was empty in 2, pH was less than 2.5 in 23, the gastric volume was greater than 0.4 ml/kg in 19, and both these risk factors were present in 17 children. The same figures in Group G were 5 (NS), 14 (P less than 0.05), 10 (P less than 0.05) and 9 (P less than 0.05) children, respectively. The antisialagogue effect was similar in both groups.

Administration, Oral↗

PubMed1991

Comparison of inhalation induction with isoflurane or halothane in children.

Thirty-six children (mean age 2.4 years) premedicated with oral chloral hydrate 70 mg kg-1 and atropine 0.03 mg kg-1 were anaesthetized with either 3.75% isoflurane or 2.5% halothane in 70% nitrous oxide in oxygen. The eyelash reflex disappeared in 39 +/- 7 s (mean +/- SD) with isoflurane and in 56 +/- 16 s with halothane (P less than 0.001). Tachypnoea was seen with both anaesthetics. Coughing, breath holding, stridorous breathing and respiratory depression were seen during isoflurane but not during halothane induction (P less than 0.01). In nine of 20 children anaesthetized with isoflurane, the ventilation had to be assisted before intubation. Endotracheal intubation was possible in 224 +/- 35 s with isoflurane and in 281 +/- 64 s with halothane (P less than 0.01). Intubating conditions were satisfactory in 80% of the children anaesthetized with either volatile agent. Cardiovascular responses to endotracheal intubation were minimal with both anaesthetics. No cardiac dysrhythmias were noted. Heart rate was higher during isoflurane than during halothane induction. Diastolic arterial pressure was lower during isoflurane than during halothane induction immediately and 5 min after intubation.

Analysis of Variance↗

PubMed1990

Unconsciousness associated with midazolam and erythromycin.

An 8-yr-old boy suffering from an asymptomatic ventricular septal defect was given erythromycin for antibiotic prophylaxis before adenoidectomy. Sixty minutes after premedication with oral midazolam 0.5 mg kg-1 and oral atropine 0.03 mg kg-1, an infusion of erythromycin 400 mg was started. When 200 mg of erythromycin had been infused, the patient lost consciousness, but other vital functions remained normal. After 45 min, he awakened spontaneously. At the time the plasma concentration of midazolam was 134 ng ml-1. In order to investigate possible interactions between midazolam and erythromycin, we studied the pharmacokinetics of midazolam in six children of the same age undergoing minor otolaryngological surgery. The plasma concentration of midazolam in the patient who lost consciousness was significantly greater than in six other children without concomitant administration of erythromycin. The altered pharmacokinetics of midazolam may result from reduced hepatic clearance of midazolam caused by an enzyme inhibiting drug, erythromycin.

Adenoidectomy↗

PubMed1990

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)

Adult↗

PubMed1989

Cimetidine and ranitidine do not affect enflurane metabolism in surgical patients.

Hepatic cytochrome-P-450-linked microsomal metabolism is inhibited by cimetidine, and to a lesser extent by ranitidine. Such an inhibition might protect against the metabolite-related toxicity of inhalation anesthetics. However, in comparison with the values measured in a control group, neither cimetidine (600 mg p.o. + 200 mg i.m.) nor ranitidine (150 mg p.o. + 50 mg i.m.), both administered 11-12 h before anesthesia, inhibited enflurane metabolism as assessed by the increase in plasma inorganic fluoride concentration and urinary fluoride excretion in 21 ASA I patients anesthetized with enflurane (end-tidal concentration 0.5 +/- 0.05% for 2-6 h). The inorganic fluoride concentration in the gastric juice remained low in all groups.

Aged↗

PubMed1988

Increase in intragastric pressure during suxamethonium-induced muscle fasciculations in children: inhibition by alfentanil.

Changes in intragastric pressure after the administration of suxamethonium 1.5 mg kg-1 i.v. were studied in 32 children (mean age 6.9 yr) pretreated with either physiological saline or alfentanil 50 micrograms kg-1. Anaesthesia was induced with thiopentone 5 mg kg-1. The incidence and intensity of muscle fasciculations caused by suxamethonium were significantly greater in the control than in the alfentanil group. The intragastric pressure during muscle fasciculations was significantly higher in the control group (16 +/- 0.7 (SEM) cm H2O) than in the alfentanil group (7.7 +/- 1.5 (SEM) cm H2O). The increase in intragastric pressure was directly related to the intensity of muscle fasciculations (regression line: y = 0.5 + 4.78x with r of 0.78). It is concluded that intragastric pressure increases significantly during muscle fasciculations caused by suxamethonium in healthy children. Alfentanil 50 micrograms kg-1 effectively inhibits the incidence and intensity of suxamethonium-induced muscle fasciculations; moreover, intragastric pressure remains at its control value.

Alfentanil↗

PubMed1988

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.

Administration, Oral↗

PubMed1988

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.

Adult↗

PubMed1988

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)

Adult↗

PubMed1988

The Otorhinolaryngology Department in Helsinki: organization and otologic research.

The organization and the otologic research in the Otorhinolaryngology Department of the University of Helsinki are described. The department has 4 surgical wards, each with 22 beds, and a new surgical wing with 6 full-sized operating rooms. The ear research is centered on middle ear histopathology and immunology, focusing especially on secretory and chronic otitis media. There is an audiological and vestibular unit, the latter is expanding rapidly. Acoustic neuroma surgery is performed as team work with a neurosurgeon. The department takes part in a cochlear implant and Audiant prosthesis program.

Audiology↗

PubMed1988

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.

Administration, Topical↗

PubMed1987

Alfentanil as an adjuvant of balanced anaesthesia for tonsillectomy in adults.

In a double-blind study, 80 adult patients, undergoing tonsillectomy, were randomly allocated to one of the four groups: d-tubocurarine (d-Tc) 50 micrograms/kg+alfentanil (Alf) 20 micrograms/kg, d-Tc 50 micrograms/kg+Alf 50 micrograms/kg, Alf 10 micrograms/kg+Alf 20 micrograms/kg, Alf 10 micrograms/kg+Alf 50 micrograms/kg. The first drug was given 2 min before thiopental and the second drug 1 min before inserting the mouth gag. Intubation was facilitated with suxamethonium. Anaesthesia was maintained with 70% nitrous oxide in oxygen and peripheral muscle relaxation during operation with vecuronium. For analysis of the induction characteristics, both d-Tc-pretreatment groups were treated together and compared with the results of the Alf-pretreatment groups. Muscle fasciculations occurred in 20% in the d-Tc group and in 70% in the Alf group. Neither d-tubocurarine nor alfentanil prevented the cardiovascular intubation response. Cardiovascular responses to the placement of the mouth gag occurred only in the lower-dose alfentanil groups. ECG changes during operation occurred in 25-45% of the patients. The most common ECG change was junctional rhythm. The operating conditions were good in 65-80% of the patients. The mean recovery score (0-10) ranged from 9.3 to 9.7 between the groups. The incidence of nausea ranged from 20-30% and that of vomiting from 10-25% between the groups. Bleeding from the operation site occurred in 20-30% of the patients. None of the patients needed sutures to stop the bleeding.

Adjuvants, Anesthesia↗

PubMed1987

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)

Acid-Base Equilibrium↗

PubMed1987

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.

Adult↗