Rescue Saline Washout for Popliteal Sciatic Block

Rescue saline washouts have been reported to reverse the effects of local anesthetic blockade in interscalene blocks and epidurals; however, evidence for their use in lower-extremity blocks is limited. This case report discusses a scenario in which a 73-year-old, 62.4 kg, female patient received an ultrasound-guided preoperative popliteal sciatic nerve block for lower extremity surgery. Subsequently, due to unforeseen circumstances, the case was cancelled, and thus the effects of the block were no longer desired. The patient wished to return home but required motor function at that time. To preserve motor function, a normal saline washout was performed at the same popliteal sciatic level under ultrasound guidance (Sonosite, Bothell, Washington). Administration of normal saline using an echogenic needle (Pajunk, Geisingen, Germany) was associated with some return of sensory function as early as 30 minutes after rescue and of motor function at three hours post-washout. This case suggests the plausibility of using a known technique, such as saline washout, to reverse the effects of nerve blockades in the setting of popliteal sciatic blocks.