Anesthesia and analgesia
-
Anesthesia and analgesia · Mar 2004
Randomized Controlled Trial Comparative Study Clinical TrialPretreatment with thiopental for prevention of pain associated with propofol injection.
Propofol causes pain on IV injection in 28%-90% of patients. A number of techniques have been tried to minimize propofol-induced pain, with variable results. We compared the efficacy of pretreatment with thiopental 0.25 mg/kg and 0.5 mg/kg and lidocaine 40 mg after venous occlusion for prevention of propofol-induced pain. One-hundred-twenty-four adult patients, ASA physical status I-II, undergoing elective surgery were randomly assigned into 4 groups of 31 each. Group I received normal saline, group II received lidocaine 2% (40 mg), and groups III and IV received thiopental 0.25 mg/kg and 0.5 mg/kg, respectively. All pretreatment drugs were made in 2 mL and were accompanied by manual venous occlusion for 1 min. Propofol was administered after release of venous occlusion. Pain was assessed with a four-point scale: 0 = no pain, 1 = mild pain, 2 = moderate pain, and 3 = severe pain at the time of propofol injection. Twenty-four patients (77%) complained of pain in the group pretreated with normal saline as compared with 12 (39%), 10 (32%), and 1 (3%) in the groups pretreated with lidocaine 40 mg, thiopental 0.25 mg/kg, and thiopental 0.5 mg/kg, respectively (P < 0.05). Thiopental 0.5 mg/kg was the most effective treatment. We therefore suggest routine pretreatment with thiopental 0.5 mg/kg along with venous occlusion for 1 min for prevention of pain associated with propofol injection. ⋯ Pain associated with IV injection of propofol is seen in 28%-90% patients. Pretreatment with thiopental 0.25 mg/kg and 0.5 mg/kg after manual venous occlusion for 1 min effectively attenuated pain associated with propofol injection. Thiopental 0.5 mg/kg was the most effective in prevention of propofol pain and can be used routinely.
-
Anesthesia and analgesia · Mar 2004
Randomized Controlled Trial Comparative Study Clinical TrialDextromethorphan-associated epidural patient-controlled analgesia provides better pain- and analgesics-sparing effects than dextromethorphan-associated intravenous patient-controlled analgesia after bone-malignancy resection: a randomized, placebo-controlled, double-blinded study.
Pain after bone malignancy surgery is intense and requires large amounts of analgesics. The augmented antinociceptive effects of dextromethorphan (DM), a N-methyl-D-aspartate receptor antagonist, were demonstrated previously. We assessed the use of postoperative patient-controlled epidural analgesia (PCEA) or IV patient-controlled analgesia (PCA) in patients undergoing surgery for bone malignancy under standardized combined general and epidural anesthesia with or without DM. Patients (n = 120) were randomly allocated to receive PCEA (ropivacaine 3.2 mg plus fentanyl 8 microg/dose) or IV-PCA (morphine 2 mg/dose) postoperatively, starting at subjective visual analog scale pain intensity >or=4 of 10 for up to 96 h. Placebo or DM 90 mg orally (30 patients/group/set) was given in a double-blinded manner before surgery and for 2 days afterwards. Diclofenac 75 mg IM was available as a rescue drug. DM patients used PCA and rated their pain >50% less than their placebo counterparts in each set, especially during the first 2 postoperative days (P < 0.01). Hourly and overall maximal pain intensity among PCEA patients was approximately 50% less than in the IV-PCA set (P < 0.01). Diclofenac was used 42% less (P < 0.01) by the PCA-DM patients compared with their placebo counterparts. Seven PCEA-DM and 11 IV-PCA-DM individuals reported having side effects compared with 44 in the PCEA-placebo and the IV-PCA-placebo groups (P < 0.01). Time to first ambulation was similar with both analgesia techniques but shorter among the DM-treated patients compared with the placebo recipients (1.5 +/- 0.8 versus 2.1 +/- 1.1 days, P = 0.02). Thus, DM afforded better pain control and reduced the demand for analgesics, augmented the PCEA effect versus IV-PCA, and was associated with minimal untoward effects in each analgesia set. DM patients ambulated earlier than placebo recipients. ⋯ Patients undergoing bone-malignancy surgery under combined general and epidural anesthesia received randomly patient-controlled epidural analgesia (PCEA) or IV patient-controlled analgesia (PCA) postoperatively and dextromethorphan (DM) 90 mg or placebo double-blindly for 3 days (n = 30/group/set). The DM effect was recorded with minimal untoward effects: it afforded better pain control and reduced the demand for analgesics compared with the placebo, especially when associated with PCEA. DM patients ambulated earlier than placebo recipients.
-
Anesthesia and analgesia · Mar 2004
Comparative StudyLocal anesthetic properties of a novel derivative, N-methyl doxepin, versus doxepin and bupivacaine.
Among various tricyclic antidepressants, doxepin and amitriptyline are also long-acting local anesthetics. We synthesized a new compound, N-methyl doxepin, and investigated whether this derivative possesses local anesthetic properties. N-methyl doxepin and doxepin were tested in a rat sciatic nerve model at 2.5, 5.0, and 10 mM. Proprioceptive, motor, and nociceptive blockade were evaluated and compared with those induced by 0.5% bupivacaine. Block of Na(+) channels by N-methyl doxepin and doxepin was assessed in cultured pituitary tumor cells under voltage clamp conditions. N-methyl doxepin elicited complete nociceptive blockade that generally lasted longer than that caused by doxepin (e.g., approximately 7.4 h versus 5.3 h at 10 mM). Significant differences were observed for full recovery of function at all concentrations and for the duration of complete blockade except at 2.5 mM. Bupivacaine at 0.5% (15.4 mM) was less effective in producing complete blockade (approximately 1.5 h) than N-methyl doxepin and doxepin. Both doxepin and N-methyl doxepin were potent Na(+) channel blockers, although N-methyl doxepin displayed a slower wash-in rate. No morphological alterations were detected in cross-sectioned sciatic nerve specimens with these three drugs. We conclude that N-methyl doxepin is a potent Na(+) channel blocker and a long-acting local anesthetic for rat sciatic nerve blockade. ⋯ N-methyl doxepin and doxepin are both potent Na(+) channel blockers; they elicit rat sciatic nerve block lasting longer than that induced by bupivacaine and seem to be nontoxic to peripheral nerves at concentrations up to 10 mM.
-
Anesthesia and analgesia · Mar 2004
Case ReportsRetroperitoneal hematoma after spinal anesthesia with the paramedian approach.
We present a case of a patient who developed a retroperitoneal bleeding after spinal anesthesia using 22-gauge Quincke needle, with the paramedian approach. Two attempts were needed to accomplish the block. Four hours later the patient complained of back pain radiating to her left calf, with weakness of the quadriceps muscle. Computed tomography revealed a large retroperitoneal hematoma from bleeding lumbar artery. Angiography failed to demonstrate the vessel. The patient was transfused with packed red blood cells and recovered gradually. She had normal coagulation tests throughout the event. ⋯ We describe a case of a large retroperitoneal hematoma after the placement of an uneventful spinal block. The patient required four units of packed red blood cells despite having normal coagulation profiles throughout the event. The diagnosis and treatment of retroperitoneal hematoma are discussed.