Regional anesthesia最新文献

Background and objectives: Spinal anesthesia is used for ambulatory surgical procedures. We provide an overview of the use of local anesthetics, use of continuous techniques, and use of adjuncts for optimization of spinal anesthesia for ambulatory surgery.

Methods: Review of current literature and critical analysis of selected manuscripts.

Results: Small doses of lidocaine (approximately 40 mg) and bupivacaine (approximately 7.5 mg) are appropriate for ambulatory surgery. Increasing concentration of local anesthetic solution may result in increased duration of anesthesia and recovery. While use of hyperbaric solutions consistently produce more cephalad sensory block, use of isobaric solutions provide adequate sensory and motor block for lower extremity surgical procedures. The use of continuous techniques may provide valuable anesthetic titration, as small doses of spinal anesthetics may produce highly variable results. Epinephrine is not recommended as an adjunct due to prolongation of recovery time. In contrast, intrathecal fentanyl may prolong surgical anesthesia without prolonging recovery.

Conclusions: Ambulatory spinal anesthesia may be optimized by selection of dose, concentration, and baricity of local anesthetic. Use of a continuous technique or an intrathecal adjunct may also be valuable means to optimize spinal anesthesia for ambulatory surgery.

Background and objectives: The potential risks of spinal lidocaine have generated interest in an alternative local anesthetic solution. Features of anesthetic block were therefore assessed in a double-blind randomized prospective study following administration of spinal bupivacaine in small doses.

Methods: Ninety patients scheduled for lower limb saphenous vein stripping were randomized to receive a 4-mL hyperbaric solution containing 4, 6, or 8 mg bupivacaine in the subarachnoid space. Sensory and motor block and hemodynamic changes were assessed at regular intervals. Patients were also questioned regarding transient radicular irritation symptoms.

Results: The mean duration of sensory block increased with increasing dose (duration at L2: 56 +/- 27, 71 +/- 29, 79 +/- 25 minutes in groups 4, 6, and 8 mg, respectively, P < .05). Motor block was also dose dependent. The incidence of grade 3 motor block increased from 0%, to 21%, and to 53%. No patient had symptoms of transient radicular irritation. Arterial pressure and heart rate were stable throughout the study.

Conclusion: Hyperbaric bupivacaine 6-8 mg provides a suitable alternative to spinal lidocaine for surgical procedures of short duration.

Background and objectives: Neurolytic superior hypogastric plexus block has been shown to be safe and effective in selected cancer patients. A large cohort of patients was studied to evaluate the continued efficacy and safety of this block in cancer patients with advanced disease.

Methods: A total of 227 pelvic pain patients with gynecological, colorectal, or genitourinary cancer who experienced poor pain control due to either progression of disease or to untoward side effects were enrolled in this study during a 3-year period. All pain patients receiving oral opioids were eligible to participate. A bilateral percutaneous neurolytic superior hypogastric plexus block with 10% phenol was performed 1 day after a successful diagnostic block with 0.25% bupivacaine.

Results: All patients reported a visual analog scale (VAS) pain score of 7-10/10 before the block. A positive response to a diagnostic block was obtained in 159 patients (79%). Overall, 115 patients of the 159 patients who responded to a diagnostic block (72%, 95% confidence interval of 65-79%) had satisfactory pain relief (VAS < 4/10), 99 (62%) after one block, and 16 (10%) after a second block. The remaining 44 patients (28%) had moderate pain control (VAS 4-7/10) after two blocks and received oral pharmacological therapy and epidural analgesic therapy with good results. Both groups experienced significant reductions in oral opioid therapy after the neurolytic blocks. No additional blocks were required by patients who had a good response during a follow-up period of 3 months. No complications related to the block were detected.

Conclusions: Neurolytic superior hypogastric plexus block provided both effective pain relief and a significant reduction in opioid usage (43%) in 72% of the patients who received a neurolytic block. Overall, this represents 51% of the patients enrolled in the study. Poor results should be expected in patients with extensive retroperitoneal disease overlying the plexus because of inadequate spread of the neurolytic agent.