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H Noorduin

Publications and source records attributed to H Noorduin.

33 records · Page 2Linked to original sources
PubMed1986

Protein binding of the analgesics alfentanil and sufentanil in maternal and neonatal plasma.

Maternal and umbilical venous plasma was obtained at delivery from 8 mothers and their neonates after an i.v. bolus injection of alfentanil, and from 6 mothers and their neonates after epidural administration of sufentanil. Plasma levels of total (free + bound) alfentanil in neonates were about 3.4-times lower than in their mothers. At 33-55 min after 30 micrograms sufentanil, total drug levels in mothers were around the limit of detection of the radioimmunoassay (0.05 ng/ml); in one mother who had received 250 micrograms, the plasma level of total sufentanil was 2.6-times higher than in her neonate. Plasma protein binding of alfentanil was 88.2% in mothers and 67.2% in neonates. Plasma protein binding of sufentanil was 90.7% in mothers and 79.3% in neonates. For both drugs, plasma protein binding was significantly related to the alpha 1-acid glycoprotein (alpha 1-AGP) level, which was about 2.5-times lower in the infants. Free alfentanil levels in mothers and neonates were similar. Free levels of sufentanil in mothers and neonates differed less from each other than did the total drug levels.

Alfentanil↗
PubMed1986

Alfentanil kinetics in renal insufficiency.

Alfentanil 100 micrograms/kg was administered as an i.v. bolus to 9 patients with severe chronic renal dysfunction (creatinine clearance 1.0 +/- 1.2 ml/min) requiring regular haemodialysis. Plasma alfentanil concentrations were measured by a specific radioimmunoassay. Individual plasma concentration-time curves were fitted to a two-compartment open model. Mean distribution and elimination half-lives were 3.7 min and 58 min, respectively. The apparent volumes of distribution of the central compartment and the total volume of distribution at steady-state were 91 ml/kg and 304 ml/kg, respectively. Alfentanil plasma clearance was 5.3 +/- 2.5 ml/min/kg. All the patients tolerated alfentanil well and no side-effects nor delayed recovery were observed.

Adult↗
PubMed1985

Epidural sufentanil for postoperative pain relief.

An open pilot study was undertaken to evaluate the analgesic properties of epidurally administered sufentanil in the early postoperative period. After orthopaedic surgery of the lower extremity, four different groups of five adult patients each received either 15 micrograms (group 1), 30 micrograms (group 2), 50 micrograms (group 3) or 75 micrograms (group 4) sufentanil via an epidural catheter previously used for the surgical procedure. Results were satisfactory in groups 3 and 4 with very good relief of pain and a mean duration of action of 372 and 307 minutes respectively. Dosage above 50 micrograms did not seem to improve the quality or duration of pain relief, although the onset of action was faster with 75 micrograms. Sedation was always present in patients with effective analgesia. In the present study respiratory depression was not evident, but three patients complained of itching and two of urinary retention.

Adolescent↗
PubMed1985

Effect of etomidate on cortisol biosynthesis: site of action after induction of anaesthesia.

To determine the site of inhibition of etomidate on cortisol biosynthesis, plasma cortisol, aldosterone, 17 alpha-hydroxyprogesterone, 11-deoxycortisol and ACTH levels were measured in healthy women before and after the administration of a single dose of either 0.20 mg kg-1 etomidate (mean value, n = 10) or 3.15 mg kg-1 thiopental (n = 9) for induction of anaesthesia in a randomized trial. Etomidate produced a smaller increase in plasma cortisol and had a later onset of action than thiopental. Plasma ACTH levels, however, rose higher in the etomidate-induced patients to reach peak levels 6 h after drug administration. In the same group, plasma aldosterone remained below the control levels but still within the normal range, whereas it rose about 2-fold in the thiopental group. Plasma levels of 17 alpha-hydroxyprogesterone and 11 beta-deoxycortisol were hardly modified after thiopental but increased significantly and remained high for 6 h after etomidate injection. This marked rise in precursors together with a blunted and delayed cortisol response to high ACTH levels, and slightly lowered plasma aldosterone concentration indicates a blockage of 11 beta-hydroxylation in adrenal cortisol synthesis after induction of anaesthesia with etomidate.

17-alpha-Hydroxyprogesterone↗
PubMed1985

Alfentanil used in the aged: a clinical comparison with its use in young patients.

The clinical effects of an i.v. bolus dose of 50 micrograms kg-1 alfentanil were studied during surgical anaesthesia in 10 elderly patients and compared with those of the same dosage in nine young adults. Plasma samples, to determine alfentanil concentrations, were taken at regular intervals during the first hour following injection. Cardiovascular changes were minor. A transient fall in systolic blood pressure shortly after the alfentanil administration was seen in both groups but was more pronounced in the elderly patients. The quality of initial intra-operative analgesia was good in all patients. The duration of action of 50 micrograms kg-1 alfentanil, as judged by the occurrence of signs of insufficient analgesia, was longer in the elderly patients (mean: 36 min) than in young patients (mean: 22 min). The alfentanil plasma levels extrapolated for these time points were similar. Hence, the difference in duration of action must be due to the slower elimination from the body in the elderly patient, rather than an increased sensitivity. On these grounds, age should be one of the criteria for selecting the appropriate dose of alfentanil.

Adult↗
PubMed1984

Alfentanil kinetics in the elderly.

Alfentanil disposition after an intravenous bolus of 50 micrograms/kg was followed in 15 elderly surgical patients and was compared to that in nine young adults. A two-compartment open model described alfentanil disappearance from plasma. Apparent volumes of distribution of the central compartment (201 and 211 ml/kg; means), at steady state (460 and 543 ml/kg), and of the AUC (746 and 722 ml/kg) in young adults and in elderly subjects did not differ. Plasma clearance was lower in elderly subjects (4.4 ml/min/kg) than in young adults (6.5 ml/min/kg), whereas terminal plasma t1/2 was longer in the elderly patients (137 and 83 min). Alfentanil dosage should therefore be reduced in elderly patients when large single doses, multiple doses, or long-term infusions are required.

Adult↗
PubMed1984

[Continuous alfentanil infusion in surgical interventions of intermediate and long duration].

Alfentanil, a new short-acting narcotic analgesic, was studied as a continuous infusion for surgical procedures of medium and long duration in 80 patients. Anaesthesia was induced with thiopentone immediately followed by 1 mg of alfentanil to attenuate the stress response to intubation. Alfentanil 100 micrograms/kg was then slowly given as a loading dose before surgery started and anaesthesia maintained by a continuous infusion at a rate of 0.5-1 micrograms/kg/min. Patients were ventilated with a 66% nitrous oxide in oxygen. The course of anaesthesia was good in 76 of the patients, while 27 needed small increments of alfentanil on top of the infusion. Cardiovascular stability was a feature in almost all patients. Recovery was extremely rapid and without complications. Naloxone to reverse respiratory depression was only used twice.

Adolescent↗
PubMed1984

General anesthesia with etomidate, alfentanil and droperidol for caesarean section.

Seventy-two pregnant women, all of them admitted for caesarean section were given etomidate and succinylcholine for induction of anesthesia. Ventilation was done with N2O/O2. Once the baby was delivered, droperidol 5 mg was injected as an anti-emetic and alfentanil 50 micrograms/kg for analgesia. At the same time an alfentanil infusion was started at a rate of 1 microgram/kg/min. The combination of etomidate, N2O/O2 and a muscle relaxant was adequate in all patients until delivery. The alfentanil infusion of 1 microgram/kg/min. appeared to be sufficient in 82% of the patients. The remaining patients needed a temporary increase of the infusion rate, which was able to abolish all stress responses immediately. Cardiovascular parameters remained quite stable, except during the period in which no alfentanil was given. Recovery was fast, patients being alert within a few minutes after surgery. Postoperative vomiting occurred in 2 patients only.

Adjuvants, Anesthesia↗
PubMed1983

Total intravenous anesthesia with etomidate, alfentanil and droperidol.

Forty-six women admitted for gynecologic surgery, were given alfentanil 1 mg, droperidol 2.5 mg and etomidate 0.3 mg/kg body weight intravenously for induction. Anesthesia was maintained using etomidate infused at a rate of 0.1 mg/kg/min for 5 minutes and at 0.01 mg/kg/min afterwards. Analgesia was achieved with a bolus injection of alfentanil prior to surgery, supplemented with additional injections of alfentanil as needed. Controlled ventilation was done with a mixture of air/oxygen. Anesthesia was uneventful in all but two patients. Blood pressure and heart rate remained stable during the entire operative period. Recovery from anesthesia was smooth, although the combination with etomidate and droperidol appears to prolong the recovery time.

Adult↗
PubMedDate not supplied

Investigation of the pharmacokinetics and analgesic effects of an intramuscular injection of sustained-release sufentanil for postoperative pain: an open study.

STUDY OBJECTIVES: To investigate the pharmacokinetics after an intramuscular (IM) injection of sufentanil in thin vegetable oil in postsurgical patients and to determine whether sustained-release IM sufentanil can provide safe and sufficient analgesia of long duration in these patients. DESIGN: Open study. SETTING: University hospital. PATIENTS: 10 ASA physical status I and II patients aged 18 to 65 years who were scheduled for elective surgery. INTERVENTIONS: All patients were premedicated with lorazepam and anesthetized with a general anesthetic technique containing nitrous oxide, fentanyl, and isoflurane. As soon as significant pain [visual analog scale score of 5 or greater (range, 0 = no pain to 10 = worst pain imaginable)] occurred during the early postoperative period, the patient received an IM injection of sustained-release sufentanil. MEASUREMENTS AND MAIN RESULTS: During the first 48 hours following surgery, blood samples were taken for determination of plasma sufentanil concentrations. Blood pressure, heart rate, respiratory rate, pain scores, and sedation scores were documented at the same time. The IM administration of sufentanil in thin vegetable oil provided sufficient pain relief, although the onset of analgesia was rather slow (+/- 1 hour). The analgesic effect was still apparent 48 hours later. Plasma concentration of sufentanil at the different time points varied from 0.021 to 0.142 ng/ml, with a mean maximal peak concentration of 0.103 ng/ml. The plasma concentration 48 hours after injection varied from 0.026 to 0.074 ng/ml. CONCLUSIONS: Although an IM injection of sufentanil in thin vegetable oil is effective for postoperative pain relief, it is associated with wide interindividual variability in plasma concentration of sufentanil and long duration of action.

Adolescent↗
PubMedDate not supplied

Epidural sufentanil for cancer pain control in outpatients.

Fifteen patients with cancer pain refractory to other methods of pain control were treated with epidural sufentanil. They all suffered from very severe or unbearable pain but had expressed the wish to spend the last period of their lives at home. On the first day of hospitalization, an epidural catheter and a portal catheter were implanted under local anesthesia. Sufentanil was delivered by a portable infusion pump into the portal catheter. The patients remained a further 2-3 days in hospital to titrate the infusion rate to their specific needs and to monitor pain relief and possible side effects. In the home situation, the patients were supervised by their general practitioners. Nine patients had epidural sufentanil as their sole analgesic till they died; six patients needed adjunctive nonepidural medications. There were no epidural- or portal-catheter related infections or cases of respiratory depression. After 1651 patient treatment days, we have found continuous epidural sufentanil infusion to be a safe and effective method for cancer pain control in outpatients.

Adult↗