Citations

Background and Objectives Interscalene brachial plexus block is a useful technique to provide anesthesia and analgesia for the shoulder and proximal upper extremity. The initial needle direction at the interscalene groove has been described as being “perpendicular to the skin in every plane” (1). A cross-sectional (axial) approach may offer a more easily conceptualized directed needle placement. The purpose of this study is to define the cross-sectional anatomy and idealized needle angles important to interscalene brachial plexus block. Methods Following IRB approval, 50 patients were studied. Cross-sectional volume coil T1-weighted magnetic resonance images (MRI) were obtained from 50 patients undergoing cervical region imaging for other reasons. At the interscalene groove, a simulated needle path to contact the ventral rami or trunks of the brachial plexus was approximated at the level of C6 or C6-C7 interspace. The angle of this needle path intersecting the sagittal plane was recorded for each patient. Results The mean angle of the simulated needle path relative to sagittal plane was determined to be 61.1 ± 6.1° (range, 50-78°). In 13 of 50 (26%) MRI scans, the cervical nerve roots were not visualized at the level of C6 and were measured at the C6-C7 level. Conclusions These findings suggest initial needle placement at the interscalene groove should be angled less perpendicularly relative to the sagittal plane than is often observed. A cross-sectional approach enables more practical visualization of initial needle placement. A more accurate initial needle placement may minimize the number of needle passes necessary to contact the nerve roots, thereby more efficiently obtaining a successful block.

Background and Objectives. A pancreatic cancer patient developing transient paraplegia compatible with spinal cord ischemia, following alcohol celiac plexus neurolysis, is described. Methods. A 58-year-old man with metastatic pancreatic cancer underwent celiac (deep splanchnic) alcohol neurolysis for management of severe epigastric and midback pain. In spite of apparently adequate needle position, he developed transient paraplegia consistent with anterior spinal artery syndrome. Results. The clinical findings suggest ischemia of the anterior spinal cord with complete motor and sensory paralysis to a T8 spinal cord level resulting from an anterior spinal artery syndrome. Conclusions. The cause of the limited bilateral transient paralysis following celiac plexus block in this patient may involve ischemia of the spinal cord associated with reversible arterial spasm following the injection of ethanol solution.

Morphine sulfate, a narcotic analgesic, possesses the undesirable side effects of central depression, tolerance, and dependency. Opiate receptors have been found in the brain and the spinal cord. Intrathecally applied opiates produce potent analgesia that can be antagonized by naloxone. The time-response study with tail-flick response after intrathecal injections of a small dosage of morphine (25 μg) demonstrated a long-lasting analgesia. Intrathecal injections of morphine or opiate-like peptides may become a predictable modality of pain relief without attendant loss of other neurologic function.