Epidural fentanyl

After epidural injection, an opioid may transfer into the cerebrospinal fluid (CSF), into the blood or bind to epidural fat, the extent depending on their lipophilicity. After epidural administration, morphine passes slowly into the CSF. Sufentanil, which is highly lipid soluble, can be detected in the plasma within 2-5 minutes after epidural injection and part of the analgesic effect of the more lipid soluble opioids may be due to a supraspinal action amplifying the direct spinal action. Epidural fentanyl and sufentanil produce a more consistent and intense analgesia than morphine, with a faster onset. Flowever, the duration is short but this can be overcome by giving them by continuous epidural infusions. 

Kotake Y, Matsumoto M, Ai K, Morisaki H, Takeda J. Additional droperidol, not butorphanol, augments epidural fentanyl analgesia following anorectal surgery. J Clin Anesth 2000 12(1) 9-13. 

The addition of bupivacaine and/or adrenaline to epidural fentanyl analgesia has also been studied in 100 women after elective cesarean section. AU received fentanyl (3 pg/ml) by patient-controUed analgesia (PCA) for 48 hours and were randomly assigned double-bUnd to receive either bupivacaine 0.01%, ephedrine 0.5 pg/ml, both, or neither (25). Patients who received fentanyl alone made more attempts at PCA than the other groups, suggesting that this regimen was less effective and the higher dose of fentanyl used perhaps contributed to a... 

In another randomized, double-blind study, 84 parturients requesting epidural analgesia were given either bupivacaine 20 ml only, followed by intravenous fentanyl 60 pg or bupivacaine 20 ml with fentanyl 60 pg followed by intravenous saline (27). The minimum local analgesia concentration (MLAC) of bupivacaine + intravenous fentanyl was 0.064% w/v and the MLAC of bupivacaine + epidural fentanyl was 0.034% w/v. The epidural fentanyl solution significantly increased the analgesic potency of bupivacaine by a factor of 1.88 compared with intravenous fentanyl. This was associated with increased pruritus with epidural fentanyl. 

Cohen S, Lowenwirt I, Pantnck CB, Amar D, Pantnck EJ. Bupivacaine 0.01% and/or epmephrme 0.5 microg/ml improve epidural fentanyl analgesia after cesarean section. Anesthesiology 1998 89(6) 1354-61. 

PoUey LS, Columb MO, Naughton NN, Wagner DS, Dorantes DM, van de Ven CJ. Effect of intravenous versus epidural fentanyl on the minimum local analgesic concentration of epidural bupivacaine in labor. Anesthesiology 2000 93(l) 122-8. 

Connelly NR, Parker RK, Vallurupalli V, Bhopatkar S, Dunn S. Comparison of epidural fentanyl versus epidural sufentanil for analgesia in ambulatory patients in early labor. Anesth Analg 2000 91(2) 374-8. 

D Angelo R, Gerancher JC, Eisenach JC, Raphael BL. Epidural fentanyl produces labor analgesia by a spinal mechanism. Anesthesiology 1998 88(6) 1519-23. 

Niemi G, Breivik H. Epidural fentanyl markedly improves thoracic epidural analgesia in a low-dose infusion of bupivacaine, adrenaline and fentanyl. A randomized, dou-ble-bhnd crossover study with and without fentanyl. Acta Anaesthesiol Scand 2001 45(2) 221-32. 

When epidural morphine (Duramorph 10 micrograms/ kg/hour) was compared with epidural fentanyl (1 micro-gram/kg/hour) and epidural hydromorphone (1 micro-gram/kg/hour) in 90 children undergoing orthopedic procedures, hydromorphone was considered to be safe and efficacious (4). The combined incidences of pruritus, nausea, and vomiting were 25, 20, and 10% respectively and for pruritus alone 35,15, and 8% respectively. 

Patient-controlled epidural fentanyl (20 micrograms with 10 minute lock-out) has been compared with patient-controlled intravenous morphine (1 mg with a 5-minute lock-out) in 48 women after cesarean section (93). Fentanyl was more efficacious in controlhng postoperative pain, with a lower incidence of nausea and drowsiness. 

In another comparison of a single dose of epidural morphine with PCA epidural fentanyl after cesarean section, pain relief and the incidence of nausea were similar, but pruritus was significantly less with fentanyl (SEDA-18, 83). 

An anaphylactic reaction to epidural fentanyl has been reported (181). 

Cooper DW, Saleh U, Taylor M, Whyte S, Ryall D, Kokri MS, Desira WR, Day H, McArthur E. Patient-controlled analgesia epidural fentanyl and i.v. morphine compared after caesarean section. Br J Anaesth 1999 82(3) 366-70. 

Shipton EA. Pruritus—a side-effect of epidural fentanyl for postoperative analgesia. S Afr Med J 1984 66(2) 61-2. 

Lam AM, KniU RL, Thompson WR, et al. Epidural fentanyl does not cause delayed respiratory depression. Can J Anaesth 1983 30 578. 

Kreitzer JM, Kirschenbaum LP, Eisenkraft JB. Epidural fentanyl by continuous infusion for relief of postoperative pain. Clin J Pain 1989 5(4) 283-90. 

Davies GG, From R. A blinded study using nalbuphine for prevention of pruritus induced by epidural fentanyl. Anesthesiology 1988 69(5) 763-5. 

Zucker-Pinchoff B, Ramanathan S. Anaphylactic reaction to epidural fentanyl. Anesthesiology 1989 71(4) 599-601. 

Fentanyl. Epidural droperidol given with epidural fentanyl improved postsurgieal analgesia following anoreetal surgery and there was less nausea eompared with fentanyl alone. ... 

Two studies " have found that chloroprocaine decreases the duration of epidural morphine analgesia (16 hours for chloroprocaine compared with 24 hours for lidocaine ). Another study found that morphine requirements after caesarean section were much higher in women who had received chloroprocaine for epidural anaesthesia than in those receiving Udocaine. The authors of one of the studies suggest that chloroprocaine should be avoided if epidural morphine is used. Epidural fentanyl also appears to be antagonised by chloroprocaine. ... 

Youssef MS, Wilkinson PA. Epidural fentanyl and monoamine oxidase inhibitors. Anaes ie-5ia(1988) 43,210-12. 

Epidural fentanyl has been used in practice since 1975. When fentanyl is placed in the epidural space, it must first cross the dura mater before it can reach the spinal cord. Epidural fentanyl binds to opioid receptors located throughout the spinal cord and nerve roots, and provides analgesia. The epidiu-al space is highly vascularized, and some redistribution of drug to the systemic circulation occiu. The epidiu-al space also contains fat, connective tissues, a lymphatic network, and the dorsal and ventral roots of the spinal nerves, all of which can serve as repositories for hpophilic agents. 

Epidural fentanyl, given as a bolus, will redistribute to the lipophilic sites found in the epidural space and limit rostral spread. However, given as a continuous infusion, those sites will become saturated and serum levels 24 hours after a continuous-rate infusion are similar to those obtained from a similar IV infusion. 

The only absolute contraindication to epidural fentanyl is in patients with known intolerance to the drug. 

The use of cervical epidural administration of fentanyl is questionable. In a study of patient-control-led cervical epidural fentanyl infusion, compared with patient-controlled IV fentanyl infusion for pain relief after pharyngolarynx surgery, results show that cervical epidural fentanyl analgesia provides marginally better pain relief at rest with no decrease in fentanyl consumption. Also, administration of fentanyl in the cervical epidural space is questionable because of the possible complications of the technique. 

The dose of epidural fentanyl should be appropriately reduced in elderly, debilitated, pregnant, or pediatric patients as well as in patients with obstructive sleep apnea. 

Epidural fentanyl can be given as a single bolus, a continuous infusion, or a combination of both. 

Epidural fentanyl 5-20 pg/h at an infusion rate of 3-10 mL/h used as solo anesthetic can provide near total analgesia with minimal side effects, while allowing the patient to ambulate safely and more comfortably. 

Prolonged infusion of epidural fentanyl may result in systemic concentrations not dissimilar to IV infusion, and therefore it is more efficacious to combine it with a low concentration of local anesthetic to get a synergistic effect. Although the addition of fentanyl to local anesthetic in the epidural space has been shown to reduce the incidence of pain in adults, this may not 186 pediatric patients. In fact, the addition of... 

Another disadvantage of epidural fentanyl is that it reduces the shivering threshold when combined with epidural local anesthetic. Epidural local anesthetics and IV opioids both decrease the core temperature, which triggers shivering. Fentanyl is often added to local anesthetic to improve the quality of epidural blockade and to reduce side effects. However, it has been shown that patients are at increased risk of hypothermia when fentanyl is added to local anesthetics. 

One great advantage of epidural fentanyl administration compared to morphine is its lower incidence and severity of adverse effects. 

Ginosar Y, Riley E, Angst M. The site of action of epidural fentanyl in humans the difference between infusion and holus administration. Anesth Analg 2003 97 1428-1438. 

Ropivacaine In 108 children who were given epidural fentanyl (0.2 micrograms/ kg/hour) in combination with ropivacaine (1.25 or 1.5 mg/ml) for postoperative analgesia after hypospadias repair, adverse effects were more common in those who... 

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