During induction, thiopentone is accidentally injected into the brachial artery. The patient immediately complains of severe burning forearm pain. Which immediate management step is MOST appropriate?
- A Apply a tight proximal tourniquet for 30 minutes to limit spread
- B Leave the needle in situ, dilute the injected alkali with saline, give intra-arterial papaverine or lidocaine, consider heparinisation and a stellate ganglion block ✓
- C Inject intra-arterial thiopentone antidote consisting of dilute hydrochloric acid
- D Immediate surgical exploration and arterial ligation above the puncture site
Correct answer: B. Leave the needle in situ, dilute the injected alkali with saline, give intra-arterial papaverine or lidocaine, consider heparinisation and a stellate ganglion block
Explanation
Thiopentone is a strongly alkaline solution with a pH around 10 to 11. Intra-arterial injection precipitates the drug, causing intense arteriolar spasm, endothelial injury and potential distal gangrene. Management aims to keep the artery patent: leave the catheter, flush with saline, administer vasodilators such as papaverine, provide sympathetic blockade, and anticoagulate if needed. Tourniquets worsen ischaemia and acidification of the vessel is never attempted.
Reference: Miller's Anesthesia, 9th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.