Intrathecal epinephrine in combined spinal-epidural analgesia for labor: dose-response relationship for epinephrine added to a local anesthetic-opioid combination.

BACKGROUND: The purpose was to investigate the dose-response relationship for intrathecally administered epinephrine added to a local anesthetic-opioid combination in combined spinal-epidural analgesia for labor, in order to evaluate analgesia and side-effects. PATIENTS AND METHODS: The subjects were 100 consecutive ASA I or II parturients at 37 weeks' gestation, who received combined spinal-epidural analgesia during labor. Each woman was randomly assigned to one of five groups that received 2-mL volumes of different spinal solutions. The control group received an intrathecal injection of bupivacaine 2.5 mg and fentanyl 25 microg only. The others received epinephrine 12.5, 25, 50 or 100 microg added to this intrathecal regimen. Maternal arterial pressure, heart rate and pain scores were recorded before and 5, 10, 15 and 30 min after intrathecal injection. Level of sensory blockade, motor blockade score, duration of intrathecal analgesia, side effects, fetal heart rate, and 1- and 5-min Apgar scores were also assessed. RESULTS: Compared to the control group, all four epinephrine groups had significantly longer duration of intrathecal analgesia, but the durations were similar. The frequencies of side effects were similar in all five groups. CONCLUSION: The results suggest that adding epinephrine to a combination of standard intrathecal doses of bupivacaine and fentanyl in combined spinal-epidural analgesia for labor significantly prolongs spinal analgesia. Of the four epinephrine doses tested, the lowest one (12.5 microg) was optimal for this clinical setting.

Effects of adding epinephrine plus fentanyl to low-dose lidocaine for spinal anesthesia in outpatient knee arthroscopy.

BACKGROUND: This study investigated whether addition of 15 microg epinephrine plus 25 microg fentanyl to lidocaine spinal anesthesia for outpatient knee arthroscopy makes it possible to use a subanesthetic lidocaine dose. The aim was to assess the quality of anesthesia and the suitability of this protocol for outpatient knee arthroscopy. METHODS: Seventy-five outpatients scheduled for knee arthroscopy were randomly assigned to one of three spinal anesthetic protocols: Group L10F25 received 10 mg of lidocaine plus 25 micro g fentanyl; Group L10F25E15 received 10 mg of lidocaine plus 25 microg fentanyl plus 15 microg epinephrine; and Group L20F25 received 20 microg lidocaine plus 25 microg fentanyl. Tourniquet pain and surgical pain were assessed using a visual analog scale. If spinal anesthesia was inadequate despite supplementary intravenous analgesia and sedation, the patient was converted to general anesthesia. Recovery times and side-effects in the early postoperative period were recorded. RESULTS: The highest level of sensory block was above the T12 dermatome in all patients. Compared with the other groups, significantly more patients in Group L10F25 converted to general anesthesia. Group L10F25 had a significantly higher mean surgical pain score than the other groups. The mean tourniquet pain score was significantly higher in Group L20F25 than Group L10F25E15. Group L10F25E15 had a significantly shorter time to discharge than the other groups. Post-operative nausea and vomiting and drowsiness were more frequent in Group L10F25 than in the other groups. CONCLUSION: The combination of 10 mg lidocaine and 25 microg fentanyl plus 15 microg epinephrine provides adequate spinal anesthesia and has favorable recovery characteristics for outpatient knee arthroscopy.

Comparison of the catheter-technique psoas compartment block and the epidural block for analgesia in partial hip replacement surgery.

BACKGROUND: The aim of this study was to compare the intra- and postoperative analgesia provided by the catheter-technique psoas compartment block and the epidural block in hip-fractured patients. We also compared hemodynamic stability, motor blockade, ease of performing the technique, and complications. METHODS: Thirty patients who underwent partial hip replacement surgery were included in this prospective single-blind study. Subjects were randomly assigned to Group E (n=15; general anesthesia plus epidural block with 15 ml of 0.5% bupivacaine) or Group P (n=15; general anesthesia plus psoas compartment block with 30 ml of 0.5% bupivacaine). Hemodynamic parameters were recorded at 10-min intervals intraoperatively. Regional anesthesia procedure time, number of attempts at block, intraoperative blood loss, and need for supplemental fentanyl and/or ephedrine were noted. Postoperatively, a patient-controlled analgesia device delivered an infusion and boluses of bupivacaine/fentanyl. Pain, motor blockade, ambulation time, patient satisfaction with analgesia, and complications were recorded postsurgery. RESULTS: The epidural required significantly more attempts than the psoas block, thus procedure time was longer in this group. Group E also showed significantly greater drops in mean arterial blood pressure from baseline at 30, 40 and 50 min after the start of general anesthesia. Significantly more Group E patients required epinephrine supplementation. The groups were similar regarding pain scores (at rest and on movement) and patient satisfaction, but Group E had higher motor blockade scores, longer ambulation time, and significantly more complications. CONCLUSION: The continuous psoas compartment block provides excellent intraoperative and postoperative analgesia with a low incidence of complications for partial hip replacement surgery

Comparison of different priming techniques on the onset time and intubating conditions of rocuronium.

BACKGROUND AND OBJECTIVE: The aim was to compare the effects of two different priming doses and priming intervals with the standard intubating dose of rocuronium on the onset time and intubation conditions. METHODS: After induction of anaesthesia, 75 patients were randomly assigned to one of five groups. Patients in Group 1 received a priming dose of rocuronium 0.06 mg kg(-1) followed 2 min later by rocuronium 0.54 mg kg(-1), Group 2 received a priming dose of 0.10 mg kg(-1) followed 2 min later by a rocuronium injection of 0.50 mg kg(-1). Group 3 was given a priming dose of 0.06 mg kg(-1) followed 3 min later by administration 0.54 mg kg(-1), where Group 4 received a priming dose of 0.10 mg kg(-1) followed 3 min later by injection of 0.50 mg kg(-1). Group 5 received a placebo injection followed 3 min later by rocuronium 0.60 mg kg(-1). RESULTS: Priming with a 3 min priming interval shortened the onset time of rocuronium irrespective of the dosage of (P < 0.001). Clinical duration of action was significantly longer after priming in Group 4 than in Group 5. Clinically acceptable intubation conditions were obtained in all patients. CONCLUSIONS: Priming with a 3 min priming interval was effective when rapid tracheal intubation with rocuronium was necessary. However, priming with rocuronium should be used carefully with special attention given to the possibility of hypoxia and aspiration of gastric contents in awake patients.

A clinical comparison of psoas compartment and inguinal paravascular blocks combined with sciatic nerve block.

The extent of inguinal paravascular blockade and psoas compartment blockade with sciatic nerve block was evaluated in 60 patients. Volumes of 30 ml and 20 ml 0.35% bupivacaine with 1/200,000 epinephrine were injected for lumbar plexus and sciatic nerve block, respectively. Complete lumbar plexus blockade was achieved in 73% of the group who were treated with the psoas compartment technique and 43% of the group who were treated with the inguinal paravascular technique. Sensory blockade of the femoral, lateral femoral cutaneous and obturator nerves was obtained in 100%, 97% and 77% of the patients in the psoas compartment group, and 93%, 63% and 47% of the patients in the inguinal paravascular group, respectively. Sensory blockade of the lateral femoral cutaneous and obturator nerves was more rapid with psoas compartment block. The study suggests that the psoas compartment block is effective in blocking the femoral, lateral femoral cutaneous and obturator nerves, but the inguinal paravascular block is only effective in blocking the femoral nerve.

Low-dose clonidine and neostigmine prolong the duration of intrathecal bupivacaine-fentanyl for labor analgesia.

BACKGROUND: Intrathecal (IT) opioid and local anesthetic combinations are popular for labor analgesia because of rapid, effective pain relief, but the duration of analgesia is limited. This study was undertaken to determine whether the addition of clonidine and neostigmine to IT bupivacaine-fentanyl would increase the duration of analgesia without increasing side effects for patients in labor. METHODS: Forty-five healthy parturients in active labor were randomized to receive a 2-ml IT dose of one of the following dextrose-containing solutions using the combined spinal-epidural technique: (1) bupivacaine 2.5 mg and fentanyl 25 microg (BF); (2) BF plus clonidine 30 microg (BFC); or (3) BFC plus neostigmine 10 microg (BFCN). Pain, sensory levels, motor block, side effects, maternal vital signs, and fetal heart rate were systematically assessed. RESULTS: Patients administered BFCN had significantly longer analgesia (165+/-32 min) than those who received BF (90+/-21 min; P<0.001) or BFC (123+/-21 min; P<0.001). Pain scores, block characteristics, maternal vital signs, Apgar scores, maternal satisfaction, and side effects were similar among groups except for nausea, which was significantly greater in the BFCN group (P<0.05 as compared with BFC). CONCLUSIONS: The addition of clonidine and neostigmine significantly increased the duration of analgesia from IT bupivacaine-fentanyl during labor, but neostigmine caused more nausea. Although serious side effects were not observed in this study, safety must be further addressed before the routine use of multiple IT drugs is advocated.

Combined use of axillary block and lateral femoral cutaneous nerve block in upper-extremity injuries requiring large skin grafts.

An axillary block and lateral femoral cutaneous nerve block combination was used in 11 patients with upper-extremity injuries requiring large skin grafts. In our experience, this block combination was highly successful. All but one of the patients obtained excellent pain relief (mean visual analog pain scores, 0.2) that required no narcotic analgesics or sedatives. There were no systemic or neurologic side effects attributed to the local anesthetic drugs. We believe that combining an axillary block and a lateral femoral cutaneous nerve block is a clinically useful and effective technique and an excellent anesthetic alternative for procedures requiring large grafts for the upper extremity.