[Continuous femoral nerve block to control postoperative pain in outpatient orthopedic surgery]. / Bloqueo femoral continuo para control del dolor postoperatorio en cirugía ortopédica ambulatoria.

OBJECTIVE: Postoperative pain is one of the most frequent complications of outpatient orthopedic surgery. We therefore studied the efficacy, feasibility, and safety of the continuous femoral nerve block as an analgesic technique for outpatient anterior cruciate ligament reconstruction. MATERIAL AND METHODS: We carried out a single-blind prospective study of ASA 1-2 patients who received a continuous femoral nerve block with 0.125% bupivacaine through an elastomeric pump to treat postoperative pain as part of a multimodal approach. Postoperative pain was assessed on a verbal numerical scale from the immediate postoperative period until 48 hours after the operation. Side effects and patient satisfaction were also assessed. RESULTS: Sixty-three patients were enrolled. The continuous femoral nerve block was effective: in the first 24 hours following surgery 90% of patients had mild or no pain, and 92% required no rescue medication. It also proved safe, as there were no significant side effects. CONCLUSION: The continuous femoral nerve block with 0.125% bupivacaine is a safe, effective option for the management of postoperative pain in outpatient anterior cruciate ligament reconstruction.

[Systemic toxicity caused by local anesthetics after peripheral nerve blocks]. / Toxicidad sistémica por anestésicos locales tras bloqueos de nervios periféricos.

Peripheral nerve blocks have aroused increasing interest in recent years, leading to a rise in the rate of complications. At the same time noteworthy technical advances have been made in areas such as nerve stimulation and ultrasound imaging, and local anesthetics have become safer. Nevertheless, the risk of anesthetic-related systemic toxicity, which manifests with neurological symptoms that tend to be forerunners of cardiovascular ones, can not be ignored. We report 2 cases of systemic toxicity due to the use of a mixture of local anesthetics during nerve blocks for outpatient surgery.

[Brachial plexus block with levobupivacaine at the humeral canal: comparison of a small volume at high concentration with a large volume at low concentration]. / Bloqueo del plexo braquial a nivel humeral con levobupivacaína: estudio comparativo alta concentración/pequeiio volumen frente a baja concentraci6n/alto volumen.

OBJECTIVE: To assess differences in the brachial plexus block in 2 groups who received the same dose of levobupivacaine: 1 group received a small volume of solution at high concentration and the other group received a large volume in solution at low concentration. MATERIAL AND METHODS: A prospective, randomized clinical trial enrolling 69 patients scheduled for wrist and/or hand surgery with a brachial plexus block with levobupivacaine in the humeral canal. Nerve stimulation was used to locate a response from the 4 terminal nerves in the brachial plexus. In the group receiving a larger volume, 10 mL of a solution of levobupivacaine at a concentration of 0.375% was used for each nerve. In the high concentration group receiving a smaller volume, levobupivacaine was used at a concentration of 0.75% in 5 mL for each nerve. Sensory latency was assessed by the pin prick technique. Motor block, the success rate (percentage), and duration of sensory and motor blockades were also evaluated. RESULTS: The full sensory block was significantly more efficacious in the large volume group than in the high concentration group (85.3% vs 51.6%, P = 0.003). A full motor block was reached in a small percentage of patients in both groups. There were no significant differences in latency or duration of block. CONCLUSIONS: The success rate was lower in the group receiving the smaller volume at a higher concentration. It is advisable to administer local anesthetics in larger volumes at lower concentrations to improve block quality. Latency and duration were similar in both groups.

[Popliteal fossa sciatic nerve block for ambulatory hallux valgus surgery: comparison of lateral and posterior approaches]. / Bloqueo del nervio ciático en el hueco poplíteo para cirugía de hallux valgus en régimen ambulatorio: comparación de los abordajes lateral y posterior.

OBJECTIVE: The aim of this study was to assess the efficacy, effectiveness, technical difficulty, and clinical usefulness of the popliteal sciatic peripheral nerve block for unilateral hallus valgux surgery and to compare the posterior and lateral approaches. We also aimed to investigate patient comfort during the procedure. MATERIALS AND METHODS: This prospective, randomized trial enrolled 60 patients scheduled for unilateral hallux valgus surgery. The patients were randomly assigned to groups of 30 patients to receive a nerve block by either a posterior or lateral approach. A nerve stimulator was used to locate the response of the two branches forming the sciatic nerve--the posterior tibial nerve and the common peroneal nerve. Then, 20 mL of 0.5% ropivacaine was injected for each nerve. Variables analyzed were efficacy, complications, quality and duration of postoperative analgesia, degree of comfort while the technique was being performed, and level of satisfaction. RESULTS: The level of comfort was good for 19 patients (70%) in the posterior approach group and for 29 (97%) in the lateral approach group (P<0.05). Level of satisfaction was good or very good for 93% and 96% of the patients in the posterior and lateral approach groups, respectively. Block efficacy was excellent for 48 patients (80%), good for 9 (15%), and poor for 3 (5%), with no significant differences between the groups. CONCLUSION: Both the posterior and lateral approaches provide easy access to the sciatic nerve for performing a block. The rate of success is high and postoperative analgesia is good, with no noteworthy complications. However, the lateral approach is more comfortable for the patient.

[The effect of propofol vs desflurane on recovery from anesthesia with remifentanil in outpatient surgery]. / Repercusión en la recuperación postanestésica de propofol frente a desflurano asociados a remifentanilo en cirugía ambulatoria.

OBJECTIVES: To compare the effect on parameters of postanesthetic recovery of propofol and desflurane administered with high doses of remifentanil for major outpatient surgery. PATIENTS AND METHODS: Seventy patients were randomly assigned to receive propofol (target concentration 1.5-2 microg/ml) or desflurane in perfusion (end expiratory concentration 0.5 MAC) during maintenance of anesthesia with remifentanil (0.25-1 microg/kg/min). The anesthetic agents were withdrawn after surgery. We recorded the times until eye opening, respiration, tracheal extubation, ability to cough, response to verbal orders and orientation. We also recorded the time until a score of 10 on the Aldrete recovery scale was attained, pain on a visual analog scale, sedation on the Ramsay scale, and instances of nausea or vomiting during the first 24 h after surgery. RESULTS: No statistically significant differences in patient characteristics, type of surgery or anesthesia were found. Times until early signs of postanesthetic recovery (eye opening, spontaneous breathing, tracheal extubation) were significantly less (p < 0.05) in the desflurane group. The groups were similar for all other parameters compared (times until ability to cough, respond to verbal orders, orientation and a score of 10 on the Aldrete scale). Duration of stay in the postanesthetic recovery unit, time in the day surgery ward and intensity of postoperative pain were also similar. The rate of postoperative nausea or vomiting was significantly lower in the propofol group. CONCLUSION: During anesthesia with remifentanil, the administration of desflurane is associated with better psychomotor recovery parameters than is propofol, but the rate of nausea and vomiting is higher with desflurane.

[Preloading with 500 ml of Hartmann's solution lessens the incidence and severity of hypotension and reduces the need for ephedrine after epidural anesthesia in ambulatory patients]. / La prehidratación con 500 ml de solución de Hartmann disminuye la incidencia e intensidad de la hipotensión y reduce las necesidades de efedrina tras anestesia epidural en pacientes ambulatorios.

INTRODUCTION: Fluid preloading to prevent hypotension after epidural anesthesia has been widely questioned, although few studies have been performed in outpatients. OBJECTIVE: To evaluate the incidence and severity of hypotension, and the need for vasoactive agents after epidural anesthesia in outpatients who did or did not receive fluid preloading. PATIENTS AND METHODS: Forty patients under 55 years of age (ASA I and II) undergoing general surgery on an outpatient basis were assigned randomly to two groups of 20 according to whether they were to receive loading with Hartmann's solution or not before epidural anesthesia. All received a similar epidural dose of 2% mepivacaine. Hypotension was defined as a decrease of 20% in systolic or mean blood pressure in comparison with baseline, or absolute pressures of < 90 and 60 mmHg, respectively. Hypotension was treated with 5 mg boluses of ephedrine. RESULTS: Fourteen patients in the non-preloading group and 5 in the preloading group developed hypotension (p < 0.05). Hypotensive episodes were fewer in patients receiving preloading fluids (0.5 +/- 1.2 versus 2.0 +/- 2.4; p < 0.05). The ephedrine dose required was higher in non-preloaded patients than in preloaded ones (10.0 +/- 12.2 versus 2.6 +/- 6.3 mg; p < 0.05). Time until presentation of hypotension was longer for non-preloaded patients. CONCLUSIONS: For patients undergoing outpatient surgery, fluid preloading with 500 ml of Hartman's solution decreases both the incidence and severity of hypotension, as well as the need for vasoactive drugs after epidural anesthesia.