Cesarean delivery under ultrasound-guided spinal anesthesia, in a parturient with poliomyelitis and Harrington instumentation

PURPOSE: To describe the anesthetic implications, and management of a medically complex parturient, who presented for Cesarean delivery (CD). The patient had poliomyelitis complicated with severe kyphoscoliosis, which had been treated with extensive spinal surgery. We used ultrasound guidance to facilitate successful spinal analgesia and anesthesia. CLINICAL FEATURES: A 27-yr-old woman, with a history of poliomyelitis and moderate restrictive lung disease secondary to kyphoscoliosis, presented at 38 weeks gestation for elective CD because of cephalopelvic disproportion. The woman had Harrington rods in situ from the level of the second thoracic vertebra, to the level of the fourth lumbar vertebra. Ultrasound guidance enabled one intervertebral space to be visualized (L5-S1), 3 cm from the expected spinal midline, and spinal anesthesia was performed at this interspace without any complications. A healthy infant was delivered, and the mother recovered uneventfully. CONCLUSIONS: Spinal anesthesia can be effectively performed in patients with poliomyelitis and severe kyphoscoliosis, that has been treated with extensive Harrington instrumentation. To facilitate regional techniques in such patients, bedside ultrasound may be greatly beneficial in identifying the correct spinal interspace.     

Ultrasound imaging in cadavers: training in imaging for regional blockade at the trunk

PURPOSE: The unique strategy of using cadaveric models for teaching ultrasound-guided blocks has been described for blocks of the upper and lower extremities. This report considers the parallels between cadaveric and live imaging relevant to scanning of the trunk. The inter-individual variation between subjects (particularly for epidural blocks) is also considered, for practicing ultrasound-guided or supported trunk and central neuraxial techniques. TECHNICAL FEATURES: Ultrasound images using a portable machine C60 5-2 MHz curved array probe or HFL38 13-6 MHz linear array probe were obtained from scanning the trunk of a male adult cadaver, and were compared with ultrasound and magnetic resonance images from an adult male volunteer. OBSERVATIONS: Ultrasound imaging at the midline of the spine in the transverse/coronal plane provided an overview of the vertebral column, while scanning in a medial-to-lateral direction using longitudinal/sagittal plane sequentially localized the spinous, articular and transverse process. At the thoracic spine, further lateral longitudinal scanning will identify costal structures with the rib necks alternating with the hyperechoic ligamentous tissue of the costovertebral joints. Ultrasound imaging in the live subject in the paramedian longitudinal plane could be used at the thoracic and lumber spinal levels to capture the optimal ultrasound window of the epidural space. Imaging in the cadaver, especially when viewing the epidural space, is primarily limited by the tissue rigidity and lack of spine flexibility. CONCLUSION: Cadavers may provide viable training options for practicing ultrasound imaging and real-time ultrasound needle guidance for nerve blocks at the trunk and epidural space. The training can be performed in a stress-free pre-clinical environment without time constraints and the potential for patient discomfort.