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PubMed1994

The effects of KB-2796 and BAY K 8644 on fentanyl-induced analgesia in rats.

We investigate the modulatory effects of subcutaneous administration of different doses of KB-2796 (1, 5 and 15 mg/kg), a new calcium channel blocker, and BAY K 8644 (0.25, 0.5 and 1 mg/kg), a calcium agonist, on fentanyl-induced analgesia (20 micrograms/kg) in rats. The drugs were tested individually as well as in combination with fentanyl. Dimethyl sulfoxide (DMSO) was used as a control. Nociceptive sensitivity was assessed by the tail-flick technique. When KB-2796 and BAY K 8644 were used alone, only KB-2796 at the dose of 15 mg/kg produced an effect that was significantly different from that of DMSO (p < 0.01). The effect was antinociceptive. When administered with fentanyl, KB-2796 at 5 and 15 mg/kg potentiated the analgesic effect of fentanyl (p < 0.05), but suppression of fentanyl analgesia by BAY K 8644 was not significant at any of the doses tested. Our data supports the hypothesis that the calcium ion is partially involved in fentanyl-induced analgesia.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1995

Nitrous oxide with fentanyl and droperidol minimizes lipid peroxidation in the liver.

We have studied the level of lipid peroxidation in the liver of rats exposed to nitrous oxide plus oxygen or injected with droperidol of fentanyl. The effect of nitrous oxide used in combination with droperidol and fentanyl was also investigated. All the tested anaesthetics caused lipid peroxidation in the rat liver. It seems likely, however, that the mechanism by which droperidol and fentanyl initiate lipid peroxidation differs from that which nitrous oxide uses. Free radical products and/or activated oxygen species are produced during fentanyl and droperidol metabolism in the liver. However, nitrous oxide is not metabolized in the liver and probably undergoes one electron reduction outside the liver thus producing free radical products and/or activated oxygen species which are able to diffuse and initiate lipid peroxidation in the liver. It was also found that the level of lipid peroxidation in the liver of rats injected with droperidol and fentanyl and then exposed to nitrous oxide was low and close to that of the control animals. We suggest that, when used in combination, the products generated outside the liver as a result of nitrous oxide metabolism are transported to the liver and take part in reactions with the products of the metabolism of droperidol and fentanyl, thus decreasing the concentration of the species able to initiate lipid peroxidation.

Animals↗
PubMed1994

Drug withdrawal symptoms in children after continuous infusions of fentanyl.

The purpose of this research was to determine the extent to which critically ill infants exhibited signs and symptoms of narcotic withdrawal after receiving continuous infusions of fentanyl. The convenience sample consisted of 12 pediatric intensive care unit (PICU) patients under 25 months of age who received fentanyl infusions for at least 24 hours. Drug withdrawal symptoms were monitored using the Neonatal Abstinence Score Tool (NAST), which assigns a score to each behavior indicative of withdrawal. A score of 8 or greater indicates Neonatal Abstinence Syndrome (NAS). Scoring began 4 hours after discontinuation of fentanyl and was conducted once per hour for 8 hours. Six subjects had a NAST score exceeding 8; these infants frequently exhibited tremors with or without stimulation, increased muscle tone, insomnia, and increased respiratory rate and effort. There were significant correlations between fentanyl dosage and NAST score (r = .76, p < 0.01), between length of infusion of fentanyl and NAST score (r = .70, p < 0.05), and between chloral hydrate dosage and NAST score (r = .62, p < 0.05). These findings suggest the need for an observation protocol and a possible weaning regimen after fentanyl is discontinued.

Critical Illness↗
PubMed1994

Enhancement of antinociceptive effect of fentanyl by KB-2796 at spinal level.

Opioids inhibit the voltage-dependent calcium channel conductance, which is one of the mechanisms of opioid analgesia on the opioid receptor. According to the hypothesis that calcium antagonists can potentiate the analgesic effect of opioids, we designed a study to investigate the effects of KB-2796, a new calcium channel blocker, on the antinociception of fentanyl at the level of the spinal cord in rats. PE-10 catheters were chronically implanted in the lumbar intrathecal space of the rats. Tail-flick test was used to assess the nociceptive sensitivity. Fentanyl (1 microgram) and KB-2796 (50, 150 or 250 micrograms) were tested individually as well as in combination. Dimethyl sulfoxide (10%) was used as a control. All drugs were injected intrathecally. Fentanyl alone produced a significant but short duration (15-30 minutes) of antinociception. KB-2796 by itself did not show any antinociception at any of the doses tested. However, when KB-2796 at the higher doses (150 and 250 micrograms) was administered with fentanyl, the antinociceptive effect was significantly (P < 0.05) enhanced over that of fentanyl alone from 30 to 180 minutes after the injection. In conclusion, our results suggest that KB-2796 potentiates the analgesic effect of fentanyl at the spinal level. These data also support our hypothesis that calcium channel blockers may involve in the antinociception of opioids.

Analgesia↗
PubMed1994

[The effect of beta-adrenergic blockade on the plasma potassium elevation induced by acute respiratory acidosis during halothane or fentanyl anesthesia].

The effect of beta-adrenergic blockade on the plasma potassium elevation induced by acute respiratory acidosis (CO2 inhalation) was studied in adult mongrel dogs during halothane or fentanyl anesthesia. Twenty-two dogs were divided into 4 groups: halothane-control (HC, n = 15), halothane-beta-blockade (H beta, n = 8), fentanyl-control (FC, n = 15) and fentanyl-beta-blockade (F beta, n = 10). Beta-blockade was achieved by continuous infusion of propranolol. The maximum levels of plasma potassium after 14% CO2 inhalation were 5.0 +/- 0.7 mM (mean +/- SD) in HC, 6.1 +/- 0.8 mM in H beta, 4.3 +/- 0.4 mM in FC and 4.8 +/- 0.5 mM in F beta. With halothane anesthesia more prominent elevation was observed in the beta-blockade group (P < 0.05), but with fentanyl anesthesia this elevation was not significantly different between the two groups. In acute respiratory acidosis, pH-induced plasma potassium elevation is suppressed by simultaneously increased catecholamines, especially epinephrine. Beta-adrenergic blockade, therefore, may cause severe hyperkalemia due to inhibition of adrenergic potassium disposal. During fentanyl anesthesia plasma potassium elevation was less marked than during halothane. This indicates that fentanyl has less suppressing action on the secretion of stress hormones, including epinephrine, under similarly stressful conditions as halothane anesthesia.

Acidosis, Respiratory↗
PubMed1993

[Comparison of buprenorphine and fentanyl for postoperative pain relief by continuous epidural infusion].

This study examined analgesic efficacy and adverse effects of buprenorphine and fentanyl for the postoperative pain relief by continuous epidural infusion. Fifty patients after upper or lower abdominal surgeries were assigned to two groups and buprenorphine and fentanyl were epidurally administered postoperatively. Buprenorphine (B) group received bolus injection of B 0.1mg + saline 8 ml and continuous infusion of B 0.8 mg+saline 92 ml (2 ml.h-1). Fentanyl group received bolus injection of F 0.1 mg+saline 6 ml and continuous infusion of F 0.6 mg+saline 84 ml (2 ml.h-1). There was no significant difference between the two groups in the analgesic efficacy, which became lower from 2 to 12 hours postoperatively. However, compared with buprenorphine group, the incidence of nausea or vomiting and dizziness was significantly less in the fentanyl group (11 vs. 4 cases and 7 vs. 1 cases). These results imply that the major site of action of epidurally administered fentanyl is the spinal cord. In contrast, analgesic effect of epidural buprenorphine appears to be enhanced by the supraspinal action. We conclude that fentanyl is superior to buprenorphine for postoperative pain relief by continuous epidural infusion.

Abdomen↗
PubMed1993

Assessment of ketorolac as an adjuvant to fentanyl patient-controlled epidural analgesia after radical retropubic prostatectomy.

BACKGROUND: Opioids, although effective postoperative analgesics, are associated with undesirable side effects. In an attempt to determine whether adjuvant, nonopioid medication would permit a reduction of the amount of fentanyl required for postoperative analgesia, the efficacy of ketorolac, an injectable nonsteroidal antiinflammatory drug, was studied as an adjuvant to fentanyl patient-controlled epidural analgesia (PCEA) for postoperative pain management following radical retropublic prostatectomy. METHODS: Forty patients were randomized into two groups to receive fentanyl PCEA and either ketorolac 30 mg intramuscularly every 6 h after an initial dose of 60 mg (n = 20) or placebo (n = 20) for 72 h. Visual analogue scale pain scores (0-100 mm; 0 mm = no pain; 100 mm = worst pain), sedation, fentanyl usage, gastrointestinal function, complications, blood loss, and temperature were assessed four times each day. RESULTS: Visual analogue scale (VAS) pain scores at rest were lower in the ketorolac group during the first 4 h (P < 0.01), but were similar thereafter. Global VAS pain scores with activity were lower in the ketorolac group on postoperative day 1 (23 +/- 4 vs. 39 +/- 6; P < 0.05) and postoperative day 2 (17 +/- 3 vs. 29 +/- 4; P < 0.05). Bladder spasm pain occurred less frequently in the ketorolac group (1 vs. 9 patients; P < 0.05). Fentanyl usage was less in the ketorolac group throughout the study (33 +/- 3 vs. 50 +/- 6 micrograms/h, 0-24 h; 20 +/- 2 vs. 36 +/- 6 micrograms/h, 24-48 h; 12 +/- 2 vs. 24 +/- 6 micrograms/h, 48-72 h; P < 0.05). Sedation scores and side effects were similar, except on postoperative day 3 when nausea was less frequent in the ketorolac group (0 vs. 6 patients; P < 0.05). Recovery of gastrointestinal function occurred sooner in the ketorolac group as determined by first bowel sounds (26 +/- 3 vs. 38 +/- 4 h; P < 0.05), first clear liquids (51 +/- 2 vs. 65 +/- 3 h; P < 0.01), and first regular meal (95 +/- 4 vs. 110 +/- 4 h; P < 0.05). There was no significant difference in blood loss, transfusion requirement, hematocrit, platelet count, or temperature. There was high overall satisfaction in both groups, but fewer patients in the ketorolac group rated pain with walking as usually or always painful (1 vs. 9 patients; P < 0.05). CONCLUSIONS: Ketorolac is a beneficial adjuvant to fentanyl PCEA for postoperative pain management after radical retropubic prostatectomy.

Analgesia, Epidural↗
PubMed1995

Plasma concentrations of fentanyl with subcutaneous infusion in palliative care patients.

1. Plasma concentrations of fentanyl were measured by g.c. in 20 patients (median age: 75 years and range: 54-86 years; eight females) in palliative care receiving the drug by continuous s.c. infusion (median rate: 1200 micrograms day-1 and range: 100-5000 micrograms day-1). 2. The infusion rate was significantly related to the duration of therapy (Spearman rho = 0.56, P < 0.05). The total steady-state plasma concentrations of fentanyl ranged between 0.1 and 9 ng ml-1, with a median of 1 ng ml-1. The unbound fraction of fentanyl in the plasma ranged from 17.8 to 44.4%, with a median value of 33.6%. Infusion rates and both total and unbound plasma concentrations of fentanyl were correlated (Spearman rho = 0.92, P < 0.05 in each case). Even with standardization for dosage, there was an eightfold variation in total plasma concentrations and 3.5-fold variation in unbound plasma concentrations of fentanyl. 3. There is considerable inter-patient variability in the pharmacokinetics of fentanyl with s.c. infusion in the palliative care setting, which necessitates careful titration of dosage according to individual clinical response.

Aged↗
PubMedDate not supplied

Comparison of morphine with and without fentanyl for epidural analgesia after major abdominal surgery.

BACKGROUND AND OBJECTIVES: The study compared bolus injection of fentanyl versus morphine to supplement epidural infusion of morphine for pain relief after major abdominal surgery. METHODS: Postoperative epidural analgesia was activated by patient request for pain relief. Thirty patients were given a loading dose (random assignment, double-blind administration) of 2 mg of morphine (group M, n = 15) or 60 micrograms of fentanyl (group F/M, n = 15), along with an epidural infusion of 0.2 mg/h of morphine. Additional boluses of 0.5 mg of morphine (group M) or 25 micrograms of fentanyl (group F/M) were given according to individual need. If patients were painfree for 3 hours, the infusion rate for morphine was reduced by 50%. RESULTS: Both treatments provided similar degrees of analgesia, although onset time was shorter for the F/M group (P < .05). To obtain 24 hours of analgesia, group M needed 18.0 mg of morphine, while group F/M needed 4.7 mg of morphine and 1.48 mg of fentanyl. For group M, mean serum concentrations of morphine decreased from 18 ng/mL at 1 hour from the start of treatment to 5 ng/mL at 24 hours. For group F/M, serum morphine stayed at approximately 4 ng/mL, but serum fentanyl increased from 0.28 ng/mL at 5 minutes to about 0.8 ng/mL at 16 hours. CONCLUSIONS: When fentanyl is added continuously to epidural morphine, the resulting higher total serum levels of opioids during prolonged treatment may increase the risk of respiratory depression. Combining the two opioids for the loading dose, however, may be valuable to shorten the onset time of analgesia.

Abdomen↗
PubMed1996

[Effects of continuous epidural administration of fentanyl and morphine on postcesarean pain].

We studied the effects of continuous epidural administration of fentanyl and morphine with bupivacaine for management of postcesarean pain. Eighteen patients received either bolus epidural administration of fentanyl 100 micrograms or morphine 3 mg with 0.5% bupivacaine 4 ml, followed by continuous infusion of fentanyl 33 micrograms.ml-1 with 0.17% bupivacaine or morphine 0.21 mg.ml-1 with 0.17% bupivacaine for 48 hours, respectively. Pain score was assessed at 0 h, 12h, 24h and 48h after leaving the operating room. Pain score increased significantly and progressively in the fentanyl group. In all cases pruritus was noted. Severe pruritus was observed in the morphine group significantly more than in the fentanyl group. The current results indicate that morphine may be preferable to fentanyl for postcesarean pain control using the present opioid doses.

Adult↗
PubMed1997

[Intravenous anesthesia by continuous administration of midazolam and fentanyl].

We examined the amount and method of administration of midazolam and fentanyl for intravenous anesthesia. Intravenous anesthesia was induced by intravenous administration of fentanyl 0.2-0.3 mg, followed by a minimal sleeping-inducing dose of midazolam, and then an additional 0.2 mg of fentanyl before starting the operation. To maintain anesthesia, a half dose of the first dose of midazolam was administered every hour, and a continuous intravenous injection of fentanyl at 0.08 microgram-1. kg-1.min-1 was also performed. It is suggested that these doses are the most suitable for obviating the use of antagonist. Also, by using a continuous administration, the dose of fentanyl can be reduced, and it is possible to stabilize circulation. Without the use of nitrous oxide during intravenous anesthesia, it is necessary to double the dose of fentanyl administered.

Adult↗
PubMed1997

Effect of low dose fentanyl-droperidol administration on respiratory drive, respiratory pattern and gas exchange in ASA 1 spontaneously breathing patients.

The aim of this study was to investigate the short term effects of low doses of fentanyl and droperidol on central respiratory drive, gas exchanges, respiratory pattern and inspiratory impedance of the respiratory system in a group of ASA 1 patients. Fourteen ASA 1 patients scheduled for minor surgery or endoscopic procedures were enrolled in the study, thirty minutes before the intervention. During spontaneous breathing of air we evaluated, by recording airflow, airway opening pressure and volume, the following variables: Respiratory Rate (RR), Tidal Volume (TV), Total respiratory cycle, Inspiratory and Expiratory Time (Ti, Te), mean inspiratory flow, P0.1, pH, PaO2 and PaCO2. After obtaining basal measurements, droperidol and fentanyl were injected and the above mentioned variables evaluated at 5 min (T1), 10 min (T2), 15 min (T3) intervals. Arterial blood was age, sampled at T3 for blood gas evaluation. The administration of droperidol (0.1 mg/kg) and fentanyl (0.002 mg/kg) significantly reduced P0.1 and Tidal Volume comparing basal with T1 and, T2 values. The other variables did not significantly modify. Two patients showed transient respiratory rhythm abnormalities in the first 180 sec following the administration of droperidol+fentanyl. Our results suggest that, in ASA 1 patients, droperidol+fentanyl preoperative administration, has no significant effects on respiratory pattern, respiratory impedance and gas exchanges: however also at low doses, the association of droperidol+fentanyl can reduce the respiratory center activity, expressed as P0.1, with a consequent reduction in Tidal Volume.

Adjuvants, Anesthesia↗
PubMed1998

Cerebral hypoperfusion after cardiac surgery and anesthetic strategies: a comparative study with high dose fentanyl and barbiturate anesthesia.

BACKGROUND: Postoperative delirium is a common sequel of cardiopulmonary bypass that is hard to diagnose correctly, difficult to predict and almost impossible to prevent and to treat. The aim of this study is to evaluate the frequency of postoperative cognitive disorders and cerebral hypoperfusion in patients receiving either high dose fentanyl or thiopentone anesthesia in cardiac surgery. METHODS: 50 unpremedicated patients, Class IIb-NYHA (25 patients in each group suffering from single critical LAD disease) undergoing elective coronary artery bypass grafting surgery were randomly allocated into two groups either to receive fentanyl 50 microg/kg with diazepam 0.1 mg/kg (Group 1) or thiopentone 7 mg/kg (Group 2) for the induction of anesthesia. Anesthesia was maintained with fentanyl 2 microg/kg/hr and diazepam 0.05 mg/kg/hr infusion in Group 1 throughout the procedure. In Group 2, it was maintained with enflurane 0.7-1.5% before and after cardiopulmonary bypass (CPB) and with thiopentone 3 mg/kg/hr infusion during CPB. Neuropsychiatric evaluation (STAI-T, min mental state examination-MMSE and Zung tests), EEG and SPECT rCBF (Single Photon Emission Computed Tomography Regional Cerebral Blood Flow) studies were performed preoperatively, early and late postoperatively. The patients that were diagnosed to have postoperative cerebral hypoperfusion also underwent computed tomography scanning postoperatively. RESULTS: Eleven patients (9 from fentanyl and 2 from thiopentone group) were diagnosed to have cerebral hypoperfusion with respect to SPECT rCBF studies. Seven of these patients (5 from fentanyl and 2 from thiopentone) were diagnosed to be in a state of delirium clinically with MMSE tests. CONCLUSION: High dose fentanyl anesthesia causes significant predisposition to postoperative cerebral hypoperfusion when compared with barbiturate anesthesia in cardiac surgery. Hypoperfusion as demonstrated by SPECT rCBF studies may play an important role in the pathophysiology of mental disorders, i.e., postoperative delirium.

Adult↗
PubMed1998

A fatal overdose of transdermally administered fentanyl.

We present a case of fentanyl overdose via mucous membrane absorption. A 31-year-old man presented to the emergency department in respiratory arrest. At intubation, a Duragesic transdermal patch (75 micrograms/h) was recovered from the buccal cavity. A second fentanyl transdermal patch (75 micrograms/h) was noted on the right lateral aspect of the thigh. Postmortem blood evaluation returned a venous fentanyl level of 17.2 micrograms/L. The therapeutic range for analgesic use is 1 microgram/L to 3 micrograms/L. Drug screens were positive for benzodiazepines and cocaine. Mass spectrophotometry/gas chromatography was used to determine fentanyl levels and to confirm drug screen results. Case history, findings at intubation, and high fentanyl blood concentration suggest the cause of respiratory arrest and death was fentanyl overdose.

Administration, Cutaneous↗
PubMed1998

[Reduction of pain on injection of propofol: a comparison of fentanyl with lidocaine].

We compared the effect of fentanyl and lidocaine on pain during injection of propofol. One hundred and sixty patients premedicated with midazolam were randomly allocated to one of four groups (n = 40, respectively); Group C, propofol 2 mg.kg-1; Group F, fentanyl 0.1 mg 3 min prior to propofol; Group L, lidocaine 40 mg added to 200 mg propofol; Group FL, fentanyl 0.1 mg 3 min prior to propofol mixed with lidocaine 40 mg. Propofol was injected via a vein on the dorsum of the hand in a half of the patients in each Group or the forearm vain in the other half. The incidence of pain was significantly less in both Group F (40%) and Group L (35%) compared with Group C (80%, P < 0.01). There was no significant difference in the incidence of pain between Group F and Group L. Group FL had the least incidence of pain (5%) of all Groups. Injection via the forearm vain tended to reduce the severity of pain compared with the vain on the dorsum of the hand. The time until loss of consciousness was significantly less in the groups receiving fentanyl than the groups without fentanyl (P < 0.01). In conclusion, prior administration of fentanyl is as effective as premixing of lidocaine in preventing the pain on injection of propofol, and the simultaneous application of them may abolish the pain.

Adult↗
PubMed1998

The peripheral effect of fentanyl on postoperative pain.

UNLABELLED: The clinical value of the analgesic effect of opioids administered peripherally (except for intraarticular administration) has not been clearly demonstrated. The aim of this study was to test the hypothesis that fentanyl, added to a local anesthetic for wound infiltration, can enhance postoperative analgesia via a peripheral mechanism. Patients with inguinal herniorrhaphy performed under spinal anesthesia were randomly assigned to one of two groups (n = 10 each). At the end of surgery, the wound was infiltrated with 10 mL of lidocaine 0.5% and fentanyl 0.001% (10 microg) in one group; in the other group, the wound was infiltrated with 10 mL of lidocaine 0.5% alone (and fentanyl 10 microg IM contralaterally). The following variables were determined in a double-blind manner: the duration of anesthesia (response to a von Frey filament), the duration of analgesia (time to mild postoperative pain), postoperative meperidine consumption, intensity visual analog scale of spontaneous and movement-associated pain 24 h after surgery, and wound pain threshold 24 h after surgery (pressure algometry). The addition of fentanyl for wound infiltration enhanced the duration of anesthesia (130+/-37 vs 197+/-27 min; P < 0.001) and decreased the intensity of spontaneous (50+/-17 vs 19+/-18 mm; P < 0.002) and movement-associated (56+/-15 vs 26+/-21 mm; P < 0.002) pain 24 h postoperatively. Differences between groups for other variables were not statistically significant. Fentanyl added to a local anesthetic for wound infiltration after spinal anesthesia can enhance postoperative analgesia by a peripheral mechanism. IMPLICATIONS: Fentanyl can enhance analgesia by a peripheral mechanism. Added to a local anesthetic for wound infiltration, it may be of benefit for the relief of postoperative pain.

Adolescent↗
PubMed1995

Comparison of fentanyl with clonidine as adjuvants for epidural analgesia with 0.125% bupivacaine in the first stage of labor: a preliminary report.

48 primiparae received epidural analgesia in labor with 10 ml of 0.125% bupivacaine with epinephrine 1:800 000, and then were divided in 4 equal groups (n = 12) to receive one of the following: 5 ml saline (B); 100 mug of fentanyl (BF); 150 microg of clonidine (BC); 75 microg of clonidine and 50 microg of fentanyl (BCF). All the patients had satisfactory analgesia. Onset was similar in the 4 groups but the duration of analgesia was significantly prolonged by the addition of either 100 microg of fentanyl or 150 microg of clonidine (respectively 89.8 min and 92.5 min vs 62.5 min) (P < 0.0001). The addition of both clonidine (75 microg) and fentanyl (50 microg) produced a considerably prolonged analgesia (177.5 min) (P < 0.0001). No episodes of bradycardia were observed. Hypotension, reversed by i.v. ephedrine, occurred in 2 patients of BCF group and in 1 patient of BF and BC groups. Only patients receiving fentanyl had pruritus. Both fentanyl and clonidine produced sedation, but both incidence and severity were greater with the mixture. No differences in neonatal outcome assessed by Apgar scores and NACS, were observed.

Journal Article↗
PubMed1995

Effect of adrenaline on plasma concentrations of fentanyl during epidural anaesthesia for caesarean section.

The present study was designed to assess the effect of adrenaline on the plasma concentrations of fentanyl in mothers and umbilical vessels after epidural administration for caesarean section. Thirty patients undergoing elective caesarean section were allocated randomly into two groups. Group 1 (n = 16) received 100 microg fentanyl, 10 ml of 0.5% bupivacaine and 10 ml 2% lidocaine, while group II (n = 14) received 100 microg fentanyl, 10 ml of 0.5% bupivacaine with adrenaline 1:200 000, and 10 ml of 2% lidocaine with adrenaline 1:80 000. Blood samples were obtained from the maternal antecubital vein (MV) at various times up to 6 hours after epidural injection, and from umbilical vein (UV) and arteries (UA) at birth for determination of plasma fentanyl by radioimmunoassay. Fentanyl Cmax and Tmax in MV did not differ significantly between the two groups. In umbilical vessels, plasma fentanyl concentrations were comparable in the two groups: (0.12 +/- 0.08 ng ml(-1) and 0.13 +/- 0.08 ng ml(-1) in UV and 0.08 +/- 0.07 ng ml(-1) and 0.06 +/- 0.05 ng ml(1) in UA of groups I and II respectively). The maximum plasma concentration in UV was 0.24 ng ml(-1) in group I and 0.25 ng ml(-1) in group II. There was no significant correlation between umbilical vessel (vein or artery):MV ratio and dose to delivery interval and no difference between the two groups in Apgar score or umbilical cord pH.

Journal Article↗