Neuraxial anesthesia for post-operative pain control after hip surgery in children with cerebral palsy and pre-existing intrathecal baclofen pumps.

PURPOSE: The purpose of this study is to describe the efficacy and adverse events of neuraxial anesthesia for post-operative pain control in non-ambulatory children with cerebral palsy with pre-existing intrathecal baclofen (ITB) pumps undergoing hip reconstructive or palliative surgery. METHODS: Twelve children (mean age 11.25 years) were included in the study with the following neuraxial anesthesia methods: indwelling epidural catheter (8 patients), neuraxial opioids administered through the side port of the ITB pump (3 patients), and single injection spinal anesthetic (1 patient). Observational pain scores and opioid requirements were quantified for all patients. RESULTS: There were no ITB pump or surgical complications at a mean follow-up of 2.2 years. The average length of stay was 6 days. Patients had good post-operative pain control with a mean observational pain score of 0.7 and mean morphine equivalent use of 0.26mg/kg/day. Four patients required anti-emetics to control nausea and three patients had urinary retention requiring repeat catheterization, but all medical complications resolved prior to discharge. CONCLUSION: Neuraxial anesthesia can effectively control post-operative pain in children with a pre-existing ITB pump. Utilizing the side port of the ITB pump for administration of neuraxial opioids is an option when epidural or spinal anesthesia is not possible.

Development of a Small Animal Ankle Arthrodesis Model.

BACKGROUND: Our understanding of the biology of ankle arthrodesis is based largely on work in spine and long bone animal models. However, the local soft tissue and vascular anatomy of the foot and ankle is different from that of the spine. Accordingly, the objective of this study was to develop a small animal ankle arthrodesis model. METHODS: A total of 12 Lewis rats successfully underwent ankle arthrodesis with stabilization consisting of a single Kirschner wire across the prepared tibiotalar joint. Based on high nonunion rates with this initial procedure, a modification was made consisting of a second pin crossing the joint. A total of 6 rats underwent the second procedure. Radiographs were taken postoperatively and in 2-week intervals up to 10 weeks. Micro computed tomography (µCT) and histological analysis was conducted at 10 weeks to assess the fusion mass. Osseous bridging of greater than 50% across the tibiotalar joint was deemed a successful fusion. RESULTS: µCT analysis determined that 11 of the 12 rats in the single-pin cohort developed nonunions (8.3% fusion rate). In the dual-pin cohort, all 6 animals successfully fused (100% fusion rate). Histological analysis supported the radiographic imaging conclusions. CONCLUSION: While the initial procedure had a high nonunion rate, enhancing the stability of the fixation greatly increased the union rate. CLINICAL RELEVANCE: The present work demonstrates the first reliable small animal ankle arthrodesis model. We believe that this model can be used in the development of novel therapies aimed at decreasing complications and increasing fusion rates.

Microgeographic variation in the diets of garter snakes.

Diets of the terrestrial garter snake (Thamnophis elegans) and the common garter snake (T. sirtalis) were studied at 22 sites in an area of about 250 km2 in northern California, during the summers of 1978-80. Overall, T. sirtalis consumed mostly amphibian and T. elegans ate an equal mixture of amphibians, fish, and leeches. However, this was more an effect of differential distribution of the two species among sites than of habitat partitioning within sites. Site was 5 times better as a predictor of diet than was species of snake. The relative frequency of T. sirtalis at the sites was correlated with the number of amphibian species.