Biomedical subjects

J Kanto

Publications and source records attributed to J Kanto.

At least 91 records · Page 5Linked to original sources

PubMed1987

Meptazinol and pentazocine: effects on prolactin, growth hormone and vasopressin levels in plasma.

The effects of two partial agonist opioid analgesics, meptazinol (at doses 0.7 and 1.4 mg/kg intravenously) and pentazocine (at doses 0.3 and 0.6 mg/kg), on anterior and posterior pituitary hormone secretion were studied in six normal human volunteers. Both drugs stimulated the secretion of prolactin dose-dependently, as expected. This effect was seen in all subjects, although two of the six subjects reacted more sensitively to both drugs. Plasma growth hormone concentrations were increased only after the higher dose of meptazinol. This was also seen in all subjects suggesting a specific pharmacological effect. Vasopressin (AVP) in plasma was greatly increased (up to 76 pg/ml) in three of the six subjects after the higher dose of meptazinol, but remained on a low level in the other three and after all other drug doses. The increase in AVP occurred only in those individuals who reported nausea after meptazinol. It was concluded that the augmented AVP release following meptazinol administration was likely to be a non-specific response induced by nausea and not an effect mediated by opiate receptors.

Adult↗

PubMed1987

Effect of antepartum ritodrine on the cardiorespiratory status of the newborn after elective cesarean section.

Heart rate (HR), heart rate variability (HRV), respiratory rate (RR) and transcutaneous PO2 and CO2 of 12 infants born by elective cesarean section were monitored during the first postnatal hour in order to evaluate the effect of the beta-mimetic tocolytic drug ritodrine. Six of the mothers received ritodrine by infusion and the other 6 physiological saline during the 2 h prepartum. The Apgar scores of the treatment group were higher (p less than 0.05) but there was a significant increase in RR (p less than 0.05) during the first hour in these babies. Arterial blood pressure (BP) was lower in the group whose mothers had received ritodrine (p less than 0.05) but there was no difference in pulse pressure. Transcutaneous pressure of CO2 (PtcCO2) of the controls decreased during the first hour (p less than 0.05). Transcutaneous pressure of O2 (PtcO2) increased during the first postnatal hour (p less than 0.01) when both groups were examined together. HR of both groups was relatively high and HRV low.

Carbon Dioxide↗

PubMed1987

Temazepam versus flunitrazepam as an oral premedication in adult surgical patients.

In a randomized study, 20 patients received temazepam 20 mg orally the night before and 20 mg in the morning of an operation performed under spinal analgesia (Group I); 20 patients received flunitrazepam I mg similarly (Group 2). Different aspects of the premedication were evaluated verbally, with the aid of a visual analogue scale, Maddox wing apparatus, the critical flicker fusion threshold test, blood pressure and heart rate measurements, serum and CSF cortisol and plasma ADH measurements, as well as CSF drug level determinations. Clinically, temazepam 20 mg proved to be comparable with flunitrazepam I mg, although the latter more effectively prevented cardiovascular changes and pre-operative hormonal stress reaction. No correlation was found between the CSF drug level (bioassayed by radioreceptor assay) and the clinical response of the two benzodiazepines, nor was there any correlation between the cortisol or ADH levels versus the CSF drug levels. On the whole, flunitrazepam proved to be marginally better than temazepam as an oral premedicant.

Administration, Oral↗

PubMed1987

Induction of general anesthesia in children with midazolam--is there an induction dose?

The pharmacodynamics of midazolam was studied in 27 children undergoing elective surgery at five different dose levels (0.075-0.6 mg/kg) in attempting to find a suitable induction dose for general anesthesia. A comparison of the highest dose was made to thiopentone 5 mg/kg. Even an induction dose of 0.6 mg/kg of midazolam was found to be unreliable in children, but effective enough to cause significant fall in systolic blood pressure after induction (p less than 0.05). In the children premedicated with atropine and pethidine thiopentone resulted in a more rapid closure of the eyes (p less than 0.01) and disappearance of the eye-lid reflex (p less than 0.01) than the high dose of 0.6 mg/kg of midazolam. Moreover, midazolam failed to induce sleep in a considerable fraction of the children even at the highest dose employed. The thiopentone group was more alert in the recovery room at 30 min after wake-up. The amnestic effect of thiopentone and midazolam were equal.

Anesthesia, General↗

PubMed1987

HELLP syndrome.

HELLP syndrome is a triad of hemolysis, elevated liver enzymes and low platelet count during pregnancy and it is proposed to be a sign of severe preeclampsia. We present two mothers with this life-threatening condition. In the first case, the syndrome appeared after a twin delivery at 34 weeks of pregnancy. The mother required 10 days of intensive care with blood and thrombocyte transfusions. Both she and the infants survived. In the second case, the mother had all classic signs of severe preeclampsia at the 27 week of pregnancy. After 3 days' intensive care, a cesarean section was performed and both the mother and the child survived.

Adult↗

PubMed1987

Midazolam as an induction agent in children: a pharmacokinetic and clinical study.

The pharmacokinetics of midazolam was studied in 21 children undergoing elective surgery at five different dose levels for induction of general anesthesia and were compared with a control group (n = 6) given thiopental, 5 mg/kg. The clearance of midazolam was found to be dose-related. The elimination half-life varied from 0.79 to 2.83 hr, which is shorter than in adult patients. Even a dose of 0.6 mg/kg midazolam was found to be unreliable as an agent for induction of anesthesia. Compared with thiopental 5 mg/kg, significantly longer times of onset to closing of the eyes (P less than 0.01) and the disappearance of eyelid reflex (P less than 0.01) were seen with midazolam.

Analysis of Variance↗

PubMed1986

Effect of induced hypotension on serum concentrations of atropine after intramuscular administration.

The serum concentrations of atropine after a single intramuscular injection of 0.01 mg/kg were determined by radioimmunoassay in nine general surgical patients during and after a combination anaesthesia and compared with those of 13 neurosurgical patients operated on during induced hypotensive anaesthesia (sodium nitroprusside plus trimetaphan). Surprisingly, comparable serum levels were found in both patient groups. We conclude that this kind of induced hypotension cannot be used as a model of drug absorption in such clinical situations as cardiac failure, haemorrhage or anaphylactic drug reactions.

Adult↗

PubMed1986

Oral temazepam as a premedicant in elderly general surgical patients.

In elderly, general surgical patients, oral temazepam 20 mg given in a soft gelatin capsule proved to be a useful light premedicant when given before spinal anaesthesia. In comparison with placebo, it caused preoperative subjective sedation, prevented an increase in heart rate and decreased serum cortisol, but not serum antidiuretic hormone levels. However, simple devices (linear analogue scale, Maddox wing test, critical flicker fusion apparatus) appeared to be quite ineffective in differentiating the clinical effects of temazepam from those of placebo. Temazepam given in a soft gelatin capsule to patients in the supine position had a reasonably fast gastrointestinal absorption, but its blood-lumbar cerebrospinal fluid penetration rate appeared to be quite slow.

Aged↗

PubMed1986

The use of oral benzodiazepines as premedications: the usefulness of temazepam.

The primary aim of premedication is to relieve the patient's anxiety/restlessness before anaesthesia and to ensure optimum quantity and quality of sleep on the night preceding surgery. With these objectives in mind, oral benzodiazepines offer a good alternative to traditional parenteral premedicants, especially as the clear anxiolytic and sedative effects of the former are of great clinical value. Oral temazepam has proven to be a valuable premedicant given on the evening before operation and/or the following morning, before surgery. Administered as a sedative in a single 20 mg oral dose the night before surgery, temazepam provided a good night's sleep in 77 percent of gynaecological surgical patients; patients slept for 7.6 hours and had no significant residual effects. As a premedicant, temazepam was as effective as parenteral diazepam or papaveretum. Temazepam's short duration of action facilitates rapid postoperative recovery in children, adults, and in the elderly. Thus, it is indicated especially for short operative procedures when rapid recovery and swift return to fitness are essential.

Anesthesia, General↗

PubMed1986

A comparison of the soft gelatin capsule and the tablet form of temazepam.

Pharmacokinetics and pharmacodynamics of the soft gelatin capsule and tablet form of temazepam were compared. In a single blind study, six healthy volunteers, in the supine position, took either a tablet of temazepam 20 mg or a soft gelatin capsule of temazepam 20 mg. Sixty gynaecological in-patients received either a tablet or a soft gelatin capsule of temazepam 20 mg the night before surgery as premedication. Subjective parameters were assessed in the morning. The soft gelatin capsule yielded clearly higher serum concentrations during the first hour after administration. In the pharmacodynamic parameters there were slight but insignificant differences in favour of the capsule form. As a premedicant the capsule resulted in a significantly (P less than 0.01) shorter delay in the onset of sedative action and to an almost significant (P less than 0.05) delay in falling asleep; also an almost significantly (P less than 0.05) longer action of sleep in comparison with the tablet.

Adult↗

PubMed1986

Importance of the interaction of midazolam and cimetidine.

Six healthy volunteers were given in an open study 15 mg of midazolam orally, and a couple of weeks later the same treatment preceded by 400 mg of cimetidine orally. We followed midazolam serum concentrations and the following pharmacodynamic parameters for five hours: subjective sedation, Maddox wing readings, critical flicker fusion frequency and peak velocity of saccadic eye movements. A statistically significant change was found in Cmax and total AUC between the two sessions. The pharmacodynamic responses differed also clearly from each other suggesting a significant change in midazolam effect even after a single oral dose of cimetidine.

Adult↗

PubMed1986

Saccadic eye movements in determination of the residual effects of flunitrazepam.

Saccadic eye movements and the subjective assessments of the volunteers were used in the determination of the residual effects of a single evening dose of flunitrazepam 0.5 mg, 1 mg and 2 mg or placebo. Sleep inducing and maintaining effects were subjectively assessed, too. Flunitrazepam at all three dose levels possessed sleep inducing and increasing effects (n = 9), but in the number of nocturnal awakenings and sedation in the morning (10 hrs after drug intake), no significant differences between placebo and the active medications were reported. However, saccadic eye movement recording could differentiate the residual effects produced by placebo or the active medication. No correlation was detected between the serum levels (radioreceptor assay) and saccadic eye movement recordings.

Adult↗

PubMed1986

Midazolam as an intravenous induction agent in the elderly: a clinical and pharmacokinetic study.

Midazolam, the first benzodiazepine derivative with water-soluble salts, was studied as an induction agent in general anesthesia for the elderly. In group 1 (n = 14), 5 or 10 mg oral diazepam was used as premedication, but in group 2 (n = 9), both oral (10 mg dixyrazin as a night-time sedative) and intramuscular (0.01 mg/kg atropine + 1 mg/kg meperidine) premedicants were used. Serum concentrations of benzodiazepines were determined using both gas-liquid chromatographic (unchanged midazolam) and radioreceptor assays (binding equivalents of benzodiazepines plus their active metabolites). In general, midazolam, 0.15 mg/kg, intravenously resulted in smooth induction of anesthesia, although the time required for induction was rather long and a sudden but transient decrease in blood pressure was found in a significant number of patients. The course of anesthesia was otherwise satisfactory. A marked amnesic effect was observed, especially when diazepam was used as premedication. The pharmacokinetic parameters based on gas-liquid chromatographic measurements were quite comparable with those in young, healthy persons published earlier. In both groups, the binding equivalents measured with radioreceptor assay (reflecting total benzodiazepine activity) were higher than the levels of unchanged midazolam determined with gas-liquid chromatography. The relatively low dose of 0.15 mg/kg of midazolam needed for anesthetic induction in the elderly indicates not pharmacokinetic, but pharmacodynamic, alterations in older patients. We conclude that midazolam is a new intravenous induction agent for use in the elderly, but careful titration of the dosage according to the response of the patient is required. Diazepam premedication prior to midazolam causes a marked anterograde amnesic effect.

Aged↗

PubMed1986

Saccadic eye movements in determination of the residual effects of the benzodiazepines.

Saccadic eye movements and the volunteers' subjective assessments were used in the determination of the residual effects of a single high evening dose of flunitrazepam 2 mg, midazolam 30 mg, and lorazepam 2.5 mg as well as in that of placebo. Sleep inducing and maintaining effects were subjectively assessed, too. Both flunitrazepam 2 mg, midazolam 30 mg, and lorazepam 2.5 mg possessed sleep inducing and increasing effects (n = 9), but in the number of nocturnal awakenings and quality of sleep no significant differences between placebo and the active medications were reported. Flunitrazepam 2 mg and lorazepam 2.5 mg produced distinct subjective residual effects thus differing from placebo and midazolam 30 mg. Despite this, saccadic eye movement recording could further differentiate midazolam 30 mg from placebo in this respect 10 hours after drug intake. After three repeated 2 mg evening doses, flunitrazepam accumulated in the serum of the volunteers (n = 6), but the effect on saccadic eye movements as well as subjective side effects began to decrease already after one day's treatment. Thus, saccadic eye movement recording proved to be a useful tool in determining the residual effects and development of tolerance of benzodiazepines. No correlation was detected between the serum levels (radioreceptor assay) and saccadic eye movement recordings or subjective residual sequelae.

Benzodiazepines↗

PubMed1986

Pharmacokinetics of atropine in children.

The serum concentration of atropine was determined both by radioreceptor assay (RRA) and by radioimmunoassay (RIA) following a single 0.02 mg/kg i.v. injection of 7 girls (age 6-15 years) and 16 boys (age 4-15 years) at the beginning of a combination anesthesia. RIA appeared to be useful in the clinical kinetic studies of this alkaloid, but RRA determined the whole antimuscarinic activity produced by atropine plus glycopyrrolate when the latter agent was used as an anticurarizing component together with neostigmine at the end of anesthesia. A biexponential serum decay curve of atropine was demonstrated by RIA with a very rapid distribution phase (t1/2 = 1-2 min) and a quite high tissue distribution (mean Vd beta = 2.6 l/kg), but due to the effective clearance of the drug (mean Cl total = 0.310-0.384 l/kg/h) the mean elimination phase half-life was around 6.5 hours. No age or gender dependency was found in the pharmacokinetics of atropine.

Adolescent↗

PubMed1986

Oropharyngeal absorption of atropine.

The oropharyngeal absorption of atropine was studied following 0.02, 0.04, 0.06 and 0.07 mg/kg doses of the drug to pregnant patients at term and compared with a 0.02 mg/kg dose given either intramuscularly or subcutaneously. The rate of systemic drug absorption was comparable following the two parenteral drug injections, but oropharyngeal atropine administration is of minor clinical significance.

Absorption↗

PubMed1986

Epidural and paracervical blockades in obstetrics. Catecholamines, arginine vasopressin and analgesic effect.

A comparative study of analgesic and endocrinologic effects of obstetrical epidural anesthesia (EA, n = 23) and paracervical block (PCB, n = 39) was performed. Pain intensity was assessed on a horizontal linear scale. Simultaneously, blood samples for the determination of concentrations of norepinephrine (NE), epinephrine (E) and arginine vasopressin (AVP) were obtained. NE and AVP levels did not bear any relationship to pain scores. Instead, the average plasma E profile during labor was practically identical with the profile of pain scores. Plasma levels of E decreased significantly after EA. A similar but short-lived effect was observed also after PCB. When comparable doses of bupivacaine were used (30 mg in the EA group and 25 mg in the PCB group); initial pain relief after EA and PCB was similar, though after 30 min the pain score increased for patients who received the PCB, while patients who received EA had continued pain relief. Faster absorption of bupivacaine was observed after paracervical than epidural injection. Decreased variability was seen in the fetal cardiograms in 25% after EA and in 33% after PCB. Transient bradycardia was observed in 2 cases after paracervical injection.

Adult↗

PubMed1986

Plasma vasopressin concentrations and serum vasopressinase activity in pregnant and nonpregnant women.

Vasopressin (AVP) concentration was measured by radioimmunoassay from unextracted plasma of nonpregnant women and during first and third trimester of pregnancy. In nonpregnant state it was 3.5 +/- 0.6 pg/ml, in first trimester 4.3 +/- 1.8 pg/ml, but in third trimester 6.5 +/- 0.4 pg/ml and significantly (p less than 0.001) higher than in nonpregnant state. AVPase activity was investigated by in vitro method whereby the decrease of AVP concentration during incubation was measured. In first trimester pregnancy, the AVPase activity was 3-fold and in third trimester 20-fold when compared with nonpregnant level.

Aminopeptidases↗