A double-blind comparison of epidural bupivacaine and bupivacaine-fentanyl for caesarean section

Comparison of epidural butorphanol and fentanyl as adjuvants in the lower abdominal surgery: A randomized clinical study

BACKGROUND

Epidural opioids acting through the spinal cord receptors improve the quality and duration of analgesia along with dose-sparing effect with the local anesthetics. The present study compared the efficacy and safety profile of epidurally administered butorphanol and fentanyl combined with bupivacaine (B).

MATERIALS AND METHODS

A total of 75 adult patients of either sex of American Society of Anesthesiologist physical status I and II, aged 20-60 years, undergoing lower abdominal under epidural anesthesia were enrolled into the study. Patients were randomly divided into three groups of 25 each: B, bupivacaine and butorphanol (BB) and bupivacaine + fentanyl (BF). B (0.5%) 20 ml was administered epidurally in all the three groups with the addition of 1 mg butorphanol in BB group and 100 μg fentanyl in the BF group. The hemodynamic parameters as well as various block characteristics including onset, completion, level and duration of sensory analgesia as well as onset, completion and regression of motor block were observed and compared. Adverse events and post-operative visual analgesia scale scores were also noted and compared. Data was analyzed using ANOVA with post-hoc significance, Chi-square test and Fisher's exact test. Value of P < 0.05 was considered significant and P < 0.001 as highly significant.

RESULTS

The demographic profile of patients was comparable in all the three groups. Onset and completion of sensory analgesia was earliest in BF group, followed by BB and B group. The duration of analgesia was significantly prolonged in BB group followed by BF as compared with group B. Addition of butorphanol and fentanyl to B had no effect on the time of onset, completion and regression of motor block. No serious cardio-respiratory side effects were observed in any group.

CONCLUSIONS

Butorphanol and fentanyl as epidural adjuvants are equally safe and provide comparable stable hemodynamics, early onset and establishment of sensory anesthesia. Butorphanol provides a significantly prolonged post-operative analgesia.

Distribution of fentanyl in the placental intervillous space and in the different maternal and fetal compartments in term pregnant women

BACKGROUND

Fentanyl is used in obstetrical practice to promote analgesia and anesthesia during labor and in cesarean delivery, with rapid and short-term effects.

OBJECTIVE

To determine fentanyl concentrations in maternal plasma, in the placental intervillous space, and in the umbilical artery and vein in term pregnant women.

PATIENTS AND METHODS

Ten healthy pregnant women underwent epidural anesthesia with fentanyl plus bupivacaine and lidocaine, and fentanyl concentrations were determined in the various maternal and fetal compartments, including the placental intervillous space, which has not been previously studied in the literature.

RESULTS

The ratios of fentanyl concentrations in the various maternal and fetal compartments revealed an 86% rate of placental fentanyl transfer. The highest fentanyl concentrations were detected in the placental intervillous space, being 2.19 times higher than in maternal plasma, 2.8 times higher than in the umbilical vein and 3.6 times higher than in the umbilical artery, with no significant differences between the umbilical vein and artery, demonstrating that there was no drug uptake by fetal tissues nor metabolism of the drug by the fetus despite the high rates of placental transfer.

CONCLUSION

The present study demonstrated that the placental intervillous space acted as a site of fentanyl deposit, a fact that may be explained by two hypotheses: (1) the blood collected from the placental intervillous space is arterial and, according to some investigators, the arterial plasma concentrations of the drugs administered to patients undergoing epidural anesthesia are higher than the venous concentrations, and (2) a possible role of P-glycoprotein (P-gp).

Extending low-dose epidural analgesia in labour for emergency Caesarean section ? a comparison of levobupivacaine with or without fentanyl

Women in labour receiving epidural analgesia with 15 ml bupivacaine 0.1% and 2 microg.ml(-1) fentanyl followed by 10-15-ml top-ups as required, who needed Caesarean section, were randomly allocated to receive 20 ml levobupivacaine 0.5% over 3 min with either 75 microg fentanyl (1.5 ml) or 1.5 ml saline. Further top-ups or inhaled or intravenous supplementation were given for breakthrough pain. Time to onset (loss of cold sensation to T4 and touch sensation to T5 bilaterally), quality of analgesia and side-effects were recorded. The study was stopped after 112 patients had been randomly assigned, due to a unit protocol change, from midwife-administered top-ups to patient-controlled epidural analgesia. Data from 51 patients given fentanyl and 54 given saline were available for analysis. There were no significant differences in onset times or supplementation between the groups, but there was more intra-operative nausea/vomiting with fentanyl (53%) than with saline (18%; p = 0.004). We found no advantage of adding fentanyl to epidural levobupivacaine when extending epidural analgesia in women already receiving epidural fentanyl during labour and there was an increased incidence of intra-operative nausea and vomiting. Power analysis suggested the same conclusion even had the study proceeded to completion.

Comparison of ropivacaine with a combination of ropivacaine and fentanyl for the caudal epidural anaesthesia of mares

Two groups of six mares aged from eight to 18 years were anaesthetised by caudal epidural injections of ropivacaine (0.5 per cent, 0.1 mg/kg) or a combination of ripovacaine (0.08 mg/kg) and fentanyl (100 microg) in a randomised study. The onset of anaesthesia was significantly more rapid (P<0.001) and it lasted significantly longer (P<0.001) in the group anaesthetised with the combination of drugs. The surgical comfort scores of the group anaesthetised with the combination were higher than those of the group anaesthetised with ropivacaine alone (P<0.001), and the quality of intraoperative analgesia, as assessed by the surgeon, was significantly improved. There were no differences between the groups in their average scores for the levels of ataxia and sedation, in their behaviour, or in the incidence of side effects.

Drug combinations in pain treatment: a review of the published evidence and a method for finding the optimal combination

The evidence of the usefulness of drug combinations in pain management is reviewed and the problem of finding the optimal combination is presented. For post-operative pain, adding a non-steroidal anti-inflammatory drug (NSAID) or paracetamol to intravenous morphine is beneficial. Adding ketamine to intravenous morphine may be advantageous, but ketamine has a narrow therapeutic window. The combination paracetamol-NSAID is probably superior to either component alone. For post-operative epidural analgesia, combinations of low doses of a local anaesthetic, an opioid and adrenaline (epinephrine) are superior to single-drug regimens. There are virtually no data on the advantages of combinations over single drugs in neuropathic and chronic musculoskeletal pain. Adding NSAIDs or ketamine to opioids may be useful in cancer pain. Because of the enormous number of possible combinations, randomized controlled trials may fail to test the optimal combination. A stepwise optimization model that has been applied in clinical investigations is presented.

Evidence-based review of the literature on intrathecal delivery of pain medication

Evidence-based medicine depends on the existence of controlled clinical trials that establish the safety and efficacy of specific therapeutic techniques. Many interventions in clinical practice have achieved widespread acceptance despite little evidence to support them in the scientific literature; the critical appraisal of these interventions based on accumulating experience is a goal of medicine. To clarify the current state of knowledge concerning the use of various drugs for intraspinal infusion in pain management, an expert panel conducted a thorough review of the published literature. The exhaustive review included 5 different groups of compounds, with morphine and bupivacaine yielding the most citations in the literature. The need for additional large published controlled studies was highlighted by this review, especially for promising agents that have been shown to be safe and efficacious in recent clinical studies.

[Postoperative locoregional analgesia in the adult: epidural and peripheral techniques. Indications, adverse effects and monitoring]

Regional analgesia is a very effective way to treat postoperative pain. Lumbar and thoracic epidural analgesia are well adapted to major abdominal and thoracic surgery. Nevertheless, respiratory side effects induced by opioids are potentially severe and an adequate monitoring is essential. In orthopaedic surgery, perineural blocks are the best technique to manage postoperative pain and perineural catheters may be used. The importance of intra-articular analgesia, simple and safe, is not fully understood. The association of a local anaesthetic inducing a minor motor block and a strong sensitive block (bupivacaine, ropivacaine), with an opioid seems to be the best pharmacologic choice regarding quality of analgesia and safety. Benefits of postoperative regional analgesia on mortality and morbidity are not demonstrated. Medical and nursing staff and specialized units should improve quality of postoperative regional analgesia as well. General guidelines for the practice of regional anaesthesia must be closely followed.

Epidural fentanyl, adrenaline and clonidine as adjuvants to local anaesthetics for surgical analgesia: meta-analyses of analgesia and side-effects

BACKGROUND

The risk/benefit ratio of adding fentanyl, adrenaline and clonidine to epidural local anaesthetics for improving intraoperative analgesia is unclear. This meta-analysis was performed to clarify this issue.

METHODS

Trials retrieved by search were considered if they were prospective, controlled, epidural analgesia (without combining general anaesthesia) was planned and occurrence of pain during surgery or side-effects were reported. Papers entered meta-analysis if they reached a predefined minimum quality score. Pooled odds ratios (OR) and confidence intervals (CI) were computed. P < 0.05 was considered as significant.

RESULTS

Eighteen trials were included in the analysis for fentanyl. Fentanyl decreased the likelihood of pain (OR = 0.21, 95% CI = 0.15-0.30, P < 0.001) and increased the incidence of pruritus (OR = 5.59, 95% CI = 3.12-10.05, P < 0.001) and sedation (OR = 1.88, 95% CI = 1.19-2.98, P = 0.003), compared to control (local anaesthetic without fentanyl). Fentanyl had no effect on respiratory depression, nausea, vomiting and Apgar score. One case of respiratory depression of a newborn was observed. Because of the very low number of trials selected, evaluation of adrenaline and clonidine was not feasible.

CONCLUSION

The analysis of current literature shows that the addition of fentanyl to local anaesthetics for intraoperative epidural analgesia is safe and advantageous. The reduction in the incidence of pain during surgery is quantitatively high and therefore clinically significant. Side-effects are mild. Randomized, controlled trials have to be performed in order to clarify the role of adrenaline and clonidine as epidural adjuvants for surgical analgesia.

Ropivacaine 7.5 mg/ml for elective caesarean section. A clinical and pharmacokinetic comparison of 150 mg and 187.5 mg

BACKGROUND

The new, long-acting local anaesthetic ropivacaine has shown less systemic toxicity than bupivacaine and a concentration of 7.5 mg/ml can therefore be used for epidural anaesthesia in Caesarean section. The present pilot study was undertaken to find indications for an optimal dosage by comparing the clinical effects, quality of anaesthesia and pharmacokinetics of ropivacaine 150 mg (lower dose = LD) vs 187.5 mg (higher dose = HD) for women undergoing elective Caesarean section under epidural anaesthesia.

METHODS

Sixteen full-term women scheduled for elective Caesarean section in two equal-sized consecutive groups received 20 or 25 ml ropivacaine epidurally in this non-randomised, open study. Study parameters included sensory and motor blockade, circulatory response, intraoperative pain and discomfort, neonatal evaluation and pharmacokinetic determinations.

RESULTS

Block height varied between T5 and T2 in the LD group, whereas the HD group produced 4 unnecessarily high blocks (C8 in 3 women and C7 in 1 woman). Surgical anaesthesia was excellent in both groups. Circulatory stability was pronounced in the LD group (no ephedrine given), while 4 women required ephedrine in the HD group. Neonatal outcome as judged by Apgar scores; umbilical blood gas determinations and NACS scores were excellent in both groups. The plasma concentration-time profiles indicated linearity in the concentration range studied, with similar clearance values to those reported previously. Placental drug equilibrium was rapid; however, the foetal drug exposure depended on intrauterine exposure time.

CONCLUSIONS

20-25 ml ropivacaine 7.5 mg/ml produced very satisfactory conditions for elective Caesarean section under epidural anaesthesia. In this small population, 150 mg ropivacaine seemed optimal, while 187.5 mg produced unnecessarily extended block height in 50% of the women.

Anesthetic quality during cesarean section following subarachnoid or epidural administration of bupivacaine with or without fentanyl

BACKGROUND

It is often assumed that subarachnoid administration of local anesthetics produces a more profound blockade than epidural anesthesia. Furthermore, the addition of fentanyl has been reported to increase preferentially intraoperative analgesia. In the present study we set out to study these two issues in a randomized and controlled study with respect to perceived pain and discomfort during surgery and postoperative pain.

METHODS

In the present study, 100 parturients subjected to elective cesarean section, 34 nullipara and 66 multipara, received one out of four combinations of the local anesthetic bupivacaine and the opioid fentanyl; group A--bupivacaine 12.5 mg + 10 micrograms fentanyl subarachnoidally, group B--bupivacaine 12.5 mg + saline subarachnoidally, group C--bupivacaine 100 mg + 100 micrograms fentanyl epidurally, group D--bupivacaine 100 mg + saline epidurally; N = 25 in each group. Pain intensity and discomfort during surgery was assessed with a visual analogue scale (VAS). Postoperative pain intensity and need for analgesics postoperatively, ketobemidone, was registered for 24 h following surgery.

RESULTS

Intraoperative pain intensity and discomfort did not differ significantly between parturients in any of the four groups Postoperative pain was significantly more intense in parturients receiving local anesthetics subarachnoidally as compared to the epidural groups during the first 6-h period. This difference was also reflected in a significantly increased consumption of analgesics during this period. No significant differences between the groups were observed with regard to hemodynamics (blood pressure), respiration (oxygen saturation) or other effects such as nausea or itching. All neonates had normal Apgar and neonatal adaptive capacity scores (NACS).

CONCLUSION

We conclude that subarachnoidal (12.5 mg) and epidural (100 mg) injections with bupivacaine both produced adequate anesthetic quality in women undergoing elective cesarean section. The addition of fentanyl (10 micrograms subarachnoidally or 100 micrograms epidurally) did not significantly improve the quality of these already profound blockades.

The antinociceptive effect of epidural lignocaine and fentanyl during lithotripsy

To determine the antinociceptive effect of combining epidural fentanyl with lignocaine during non-immersion lithotripsy, 56 healthy patients were enrolled into a prospective, randomized, double-blind study. Epidural anaesthesia was induced with either lignocaine 300 mg alone, or lignocaine 300 mg, or 200 mg in combination with fentanyl 100 micrograms. Throughout the procedure analgesia was assessed by comparing the incidence of (a) spontaneous complaints of pain, (b) patients' attempts to withdraw from the painful stimulus, (c) supplemental epidural lignocaine requirements, (d) the haemodynamic response to lithotripsy and (e) the time to first postoperative pain. The patients who received the fentanyl-lignocaine 300 mg combination required no supplemental lignocaine, experienced marginally less intraoperative pain and recorded lower mean arterial blood pressures when compared with lignocaine 300 mg alone. However, when the combination of lignocaine 200 mg and fentanyl 100 micrograms was administered, patients experienced significantly more pain, withdrew from the painful stimulus more often and received more supplemental lignocaine when compared with the other two treatment groups. No difference was found in the time to the first complaint of postoperative pain. Similarly, discharge times were unaffected by treatment modality. We conclude that despite the addition of fentanyl, adequate analgesia during lithotripsy is dependent upon the dose of local anaesthetic administered.

Epidural fentanyl improves the onset and spread of epidural mepivacaine analgesia

PURPOSE

To determine the extent of enhanced blockade by the combined use of epidural fentanyl and mepivacaine. We compared the onset of hypoalgesia, analgesia and the threshold of pressure pain.

METHODS

Thirty patients were randomly divided into three groups. The fentanyl group received 10 ml saline containing 0.1 mg fentanyl, mepivacaine group received 10 ml mepivacaine 1% and a mixed group received 10 ml mepivacaine 1% with 0.1 mg fentanyl. All solutions, without epinephrine, were injected through an epidural catheter at T5-6 to T6-7. The change in sensation, loss of pin-prick and pain threshold sensation, measured by pressure algometer, were assessed at 2.5-min intervals for 15 min at the T4 dermatome. Spread of analgesia was determined at 15 min.

RESULTS

Loss of pinprick was more rapid in the mixed, 11.0 +/- 2.7 (SD) min, than in the mepivacaine group, 15.0 +/- 2.9 min, (P < 0.05), although there was no difference in change of sensation. Pressure pain threshold increased with time in the mepivacaine (P < 0.05) and mixed (P < 0.05) groups. It was higher in the mixed than in the fentanyl and mepivacaine groups at 5, 7.5 and 10 min (P < 0.05). The lower level of analgesia was lower in the mixed than in the mepivacaine groups (P < 0.05). Blood pressure was unchanged in the three groups, but heart rate decreased at 7.5, 10, 12.5, and 15 min in the mepivacaine and mixed groups (P < 0.05).

CONCLUSIONS

The addition of fentanyl to mepivacaine accelerates the onset of analgesia and enhances the analgesic effect of epidural block.

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.

Combined spinal epidural (CSE) analgesia: technique, management, and outcome of 300 mothers

Epidural analgesia in labour is commonly associated with some degree of lower limb weakness often severe enough to be described as paralysis by the mother. We aimed to produce rapid reliable analgesia with no motor block throughout labour. We report a pilot survey of 300 consecutive women requesting regional analgesia in labour who received a combined spinal epidural blockade (CSE). The initial dose was given into the subarachnoid space and analgesia maintained via an epidural catheter. A subarachnoid injection of 2.5 mg bupivacaine and 25 mug fentanyl was successfully given in 268 women (89.3%). Completely pain-free contractions within 3 min of this injection occurred in 195 women (65%) and in all 300 within 20 min and there was no associated motor block in 291 (97%). 141 women chose to stand, walk or sit in a rocking chair at some time during labour. Only 38 women (12.6%) were immobile during the first stage of labour. Analgesia was maintained via the epidural catheter with bolus doses of 10-15 ml of 0.1% bupivacaine and 0.0002% fentanyl. The mean bupivacaine requirement was 9.5 mg/h throughout the entire duration of analgesia. The incidence of post lumbar puncture headache was 2.3%. Transient hypotension occurred in 24 women (8%) and was treated with 6 mg intravenous boluses of ephedrine. Complete satisfaction with analgesia and mobility was reported 12-24 h post partum by 95% of mothers. The use of this analgesic technique caused no alteration in obstetric management or post partum care of the women.

Comparison of two fentanyl doses to improve epidural anaesthesia with 0.5% bupivacaine for caesarean section

Ninety women undergoing elective caesarean section under epidural anaesthesia were double blindly randomised into three groups to receive either 2 ml of saline or 50 or 100 micrograms of fentanyl in 2 ml volume added to 0.5% bupivacaine. Both doses of fentanyl intensified the epidural anaesthesia and reduced patient discomfort during the operation. In both fentanyl groups the epidural blockade more often reached the 5th thoracic segment (P = 0.0258), the patients had significantly less pain (P = 0.0256), needed less intravenous diazepam medication during the operation (P = 0.0005) and the operating conditions were were better when compared to the saline group (P = 0.0416). There was no difference between the groups in the condition of the neonates as assessed by the Apgar score and cord blood pH. The postoperative time until treatment for pain was requested by the patients was more than 1 h longer in the fentanyl groups, but there was no difference in the total amount of postoperative analgesics needed during the first 24 h when compared to the saline group. Mild pruritus not requiring treatment was more common in fentanyl groups than in the saline group (P = 0.0187). The results suggest that 50 micrograms of fentanyl added to 0.5% bupivacaine increases patient comfort and improves the quality of epidural anaesthesia for caesarean section, and that adding 100 micrograms does not give further advantage.

A comparison of two doses of epidural fentanyl during caesarean section

A prospective, randomized, double-blind study was performed to compare the analgesic efficacy and side effects of epidural fentanyl, 25 micrograms vs 50 micrograms, when used to supplement epidural anaesthesia for elective Caesarean section. Fifty ASA I and II patients were randomized into two groups: Group I (n = 24) received 25 micrograms and Group II (n = 26) received 50 micrograms of epidural fentanyl after the epidural test dose. No differences between the two groups were found on any measures of intraoperative pain, nausea, drowsiness, respiratory depression, hypotension, pruritus and neonatal outcome. The low levels of pain experienced by patients indicates that doses higher than 50 micrograms of epidural fentanyl are usually unnecessary for optimal analgesia.

Alkalinization improves the quality of lidocaine-fentanyl epidural anaesthesia for caesarean section

This double-blind randomized study of 116 healthy women was undertaken to evaluate whether alkalinization potentiated the analgesic effects of epidural fentanyl-lidocaine for elective Caesarean section. After a test-dose of 3 ml, lidocaine 2% with adrenaline 1:200,000, all patients received 100 micrograms, fentanyl in 5 ml saline and they were then divided into two groups, to receive incremental doses of 5 ml lidocaine 2% with adrenaline 1:200,000 with or without 0.1 mEq.ml-1 sodium bicarbonate, to obtain anaesthesia to T4. The addition of bicarbonate to lidocaine resulted in a mean (SD) pH increase from 6.58 (0.01) to 7.14 (0.02) and in a mean PCO2 increase from 3.8 (0.8) to 345.1 (5.9) mmHg. Onset of sensory analgesia to the S1 segment as well as the interval between the block and the delivery of the baby were shorter in the bicarbonate group (respectively 15.4 (6.9) vs 18.9 (4.8) min and 28.9 (9.5) versus 33.9 (11.8) min; P < 0.01 and 0.05). No differences were noted in the onset to T4 or in the degree of motor block. The percentage of patients experiencing pain during surgery and requiring intravenous analgesics was higher in the group which did not receive bicarbonate (3% vs 16%; P < 0.05). There were no differences in intraoperative maternal side-effects, neonatal outcome or in maternal venous and umbilical venous and arterial lidocaine concentrations between the groups. The concentrations of fentanyl in maternal plasma, umbilical artery, and the umbilical artery to maternal vein ratio were greater in the alkalinized group (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Neonatal effects of adding epidural fentanyl to 0.5% bupivacaine for caesarean section

Epidural injection of opioids has been introduced to improve analgesia during labour and caesarean section. This study was designed to quantify placental transfer of fentanyl and to evaluate neonatal effects of adding fentanyl to 0.5% bupivacaine for epidural anaesthesia in women undergoing elective caesarean section at term. The parturients were randomly allocated to one of four groups of 20, who received either saline (control) or 50, 75 or 100 microg of fentanyl added to 20 ml of 0.5% bupivacaine. Apgar scores, time to sustained respiration and umbilical acid-base values did not differ among the groups. The median (interquartile range) umbilical artery to maternal vein fentanyl concentration ratio was 0.34 (0.26-0.48) when the fentanyl groups were taken together. Neurologic and adaptive capacity scores were evaluated at 2 and 24 h. Neonates whose mothers received fentanyl had lower scores with regard to supporting reaction at 2 h and active tone at 24 h, when compared to controls (P<0.05), but there were no differences among the groups with regard to the other test criteria in the neurobehavioural test. In conclusion, epidural injection of fentanyl 50-100 microg did not produce depression of the term neonate.

Maternal effects of adding epidural fentanyl to 0.5% bupivacaine for caesarean section

Epidural injection of fentanyl added to 0.5% bupivacaine improves epidural anaesthesia during caesarean section. The present prospective randomized double-blind study sought to determine the lowest effective dose of fentanyl. Eighty healthy women at term were divided into four groups of 20, with each group receiving a different 2 ml study solution: saline (control) or 50, 75 or 100 microg of fentanyl added to 20 ml of 0.5% bupivacaine. Additional increments of 0.5% bupivacaine were administered as required at 30 min and onwards until a bilateral block to T4 was attained. The onset, duration and segmental level of analgesia, and degree and duration of motor block were not influenced by the addition of fentanyl. Peroperative quality of analgesia was improved, as the request for supplementary analgesics was less following the addition of 75 or 100 microg of fentanyl (P < 0.05). Postoperatively the time to first supplemental opioid request was prolonged and pain was reduced for at least 6 h from induction of anaesthesia when 75 or 100 microg of fentanyl had been added (P < 0.05). Pruritus was the only side-effect (P < 0.05). In conclusion, fentanyl 75 microg was the lowest effective dose for improving quality of analgesia. Onset time was not reduced by the addition of fentanyl.

Analgesic efficacy and safety of a caudal bupivacaine-fentanyl mixture in children

The analgesic efficacy and safety of a single caudal injection of a bupivacaine-fentanyl mixture was investigated in this prospective, controlled, triple-blinded study of 34 children, aged 1-11 yr and of ASA physical status I-II undergoing urological surgery. After induction of anaesthesia and before surgery, the children were randomly assigned to receive a caudal injection of 1.0 ml.kg-1 bupivacaine 0.125% with epinephrine 1:400,000 and either fentanyl 1.0 microgram.kg-1 in 1.0 ml of normal saline or 1.0 ml of normal saline. After completion of surgery, patients were assessed in the recovery room for six hours from the time of the caudal injection and for a further 18 hr on the ward. While in the recovery room arterial oxygen saturation and respiratory rate were monitored continuously and recorded hourly together with end-tidal carbon dioxide, pain and sedation scores. Other complications were also recorded. While on the ward, pain and sedation scores, respiratory rate and side effects were recorded every two hours. Postoperative analgesia was provided by intravenous morphine. Analgesic requirements were recorded for the 24-hr study period. Pain and sedation scores did not differ between groups. Respiratory depression or hypoxia did not occur. The incidences of other side effects did not differ. There were no differences in the numbers of patients requiring morphine within eight hours, the time to first morphine administration or the total morphine requirements. We conclude that a single caudal injection of a bupivacaine-fentanyl mixture with epinephrine administered prior to surgery, while safe, offers no advantage over an injection of bupivacaine 0.125% with epinephrine for paediatric urological surgery.

Epidural fentanyl and caesarean section: when should fentanyl be given?

Epidural fentanyl is often added to epidural local anaesthetic agents to improve the quality of anaesthesia obtained during Caesarean section. Fentanyl may be given either before or after delivery of the infant. When given before delivery, fentanyl has not been reported to cause neonatal depression, although this remains a concern. A prospective, randomized, double-blind study was undertaken to determine if fentanyl was more effective if given before or after delivery of the baby in 64 women undergoing Caesarean section under lidocaine epidural anaesthesia. Maternal outcome was determined by time to achieve T4 neural blockade, the dose of lidocaine necessary to achieve this block and intraoperative scores for pain, nausea, vomiting, shivering, and sedation. Neonates were assessed by umbilical arterial blood pH and Apgar scores. No differences were detected in either group with respect to maternal or neonatal outcome. We recommend using only epidural local anaesthetic agents before delivery, and giving epidural fentanyl following delivery of the infant.

Pulmonary hypertension and cardiomyopathy: anaesthetic management for caesarean section

Pulmonary hypertension in pregnant women is uncommon but is associated with a high mortality. We present the case of a 14-yr-old parturient with pulmonary hypertension and cardiomyopathy who required a Caesarean section. Management goals included: (1) maintaining right ventricular function, (2) avoiding the haemodynamic effects of general endotracheal anaesthesia, and (3) minimizing narcotic-related neonatal respiratory depression. While most authors agree on invasive pulmonary and systemic monitoring, opinions differ as to the optimal method of providing anaesthesia for these patients. The successful use of lumbar epidural anaesthesia with lidocaine and fentanyl is described. When the local anaesthetic was administered slowly and in increments, epidural anaesthesia was safe for both mother and fetus.

Does combined epidural lignocaine and fentanyl provide better anaesthesia for ESWL than lignocaine alone?

The efficacy of epidural fentanyl combined with lignocaine 1.5% with adrenaline 1:200,000 was studied in a randomised, double-blind, controlled trial of two hundred patients undergoing extracorporeal shock wave lithotripsy with or without ancillary procedures. The quality of anaesthesia was assessed using linear analogue pain scores, the patient's impression, and the rate of intra-operative intervention by the anaesthetist. Postoperative symptomatology was also recorded. The only significant difference lay postoperatively in that the fentanyl-ancillary procedure sub-group had less pain approximately one hour postoperatively (P = 0.01). In the context of this study and in the presence of an adequate autonomic and somatic local anaesthetic blockade, the addition of epidural fentanyl does not appear to confer any significant advantage other than to enhance postoperative analgesia.