Regional Anesthesia (also see Chapter 43 and Chapter 44 )

Regional anesthesia is likely to be both safe and effective in a hyperbaric environment by avoiding the requirement for mechanical ventilation. Bowel resection has been performed at an ambient pressure of 6.75 ATA in a helium-O₂ environment with the local injection of lidocaine supplemented with parenteral meperidine. ^[196] When administering intravenous solutions for spinal or epidural anesthesia at increased ambient pressure, care should be taken to avoid injecting air bubbles, which would then expand during decompression and could cause symptoms. Extreme care should be taken to ensure sterile technique because of the propensity for enhanced bacterial growth in the warm, humidified environment of a hyperbaric chamber, particularly during saturation chamber exposure.