Use of saline solution to reverse interscalene block-induced phrenic nerve palsy: A case report.

Brachial plexus block at the interscalene level is a regional anaesthetic technique widely used to provide analgesia in shoulder and upper extremity surgery; However, it is associated with a high incidence of phrenic nerve block with diaphragmatic paralysis which has clinical implications in patients with underlying respiratory disease, showing respiratory difficulty symptoms. As consequence, it has been contraindicated in certain population groups. Once diaphragmatic paralysis and respiratory symptoms are established, management is supportive and expectant. In recent years, the administration or "washing" with normal saline solution has been described with the same approach, to reverse the phrenic nerve block and thus the respiratory symptoms. We present the first case of successful reversal of phrenic nerve block with saline in Latin America.