[Unilateral phrenic nerve paralysis after vertical infraclavicular plexus block]

Area of Science:

• Anesthesiology
• Neurology

Background:

• Brachial plexus blockade is a common regional anesthesia technique.
• Vertical infraclavicular approach is frequently used for upper extremity surgery.

Observation:

• A patient developed rapid onset phrenic nerve block post-brachial plexus anesthesia.
• Oxygen saturation (SpO2) dropped to 80% within five minutes of local anesthetic injection.
• Postoperative radiography revealed an elevated ipsilateral diaphragm.

Findings:

• The phrenic nerve block was reversible, with oxygen supplementation discontinued after five hours.
• Diaphragm position normalized by the following day, confirmed by X-ray.
• This indicates a transient effect of the local anesthetic on the phrenic nerve.

Implications:

• Awareness of potential phrenic nerve involvement is crucial during infraclavicular brachial plexus blocks.
• Prompt recognition and management of hypoxemia are necessary.
• The reversible nature suggests careful monitoring rather than invasive intervention is often sufficient.