LAUSR

A 45-year-old, 80 kg patient, an operated case of fracture humerus, was scheduled to undergo percutaneous screw removal. All his preoperative investigations were within normal limits. Previous surgery was done 2 weeks earlier under brachial plexus block (BPB) given by the supraclavicular approach. Both surgery and anaesthesia had been uneventful. Patient was shifted to the operation theatre, midazolam (2 mg) was injected intravenously (IV) for premedication. Injection ceftriaxone 1 gm (after checking prior antibiotic sensitivity by intradermal skin testing, reported as negative) was added to the IV fluid. A supraclavicular BPB was given (bupivacaine + clonidine) after negative aspiration for blood. Within a few minutes of administering the local anaesthetic (LA), patient developed severe agitation and delirium and became very violent. In the next few minutes, patient developed rashes, urticaria and flushing over forearms and chest, spreading to the face and neck. All vitals remained stable with no other systemic manifestations. A differential diagnosis of LA systemic toxicity was made apart from anaphylaxis to antibiotic and possibly latex. Antibiotic infusion was stopped. Intralipid was kept ready but because of stable haemodynamics, its administration was withheld. In view of continuous severe agitation, restlessness, delirium and a possible diagnosis of anaphylaxis, patient’s trachea was intubated. During laryngoscopy, oedema of the uvula was seen. There was still no cardiovascular collapse or bronchospasm; however, the flushing had spread to the abdomen and thighs. A provisional diagnosis of anaphylaxis (Grade I) was made and 0.5 mg of epinephrine was given intramuscularly. Inj. pheniramine maleate 45 mg and inj. hydrocortisone 200 mg was also administered IV. Ten minutes after administration of epinephrine all cutaneous symptoms resolved. Since the patient’s condition was stable, surgeons were asked to proceed and at the end of uneventful surgery, trachea was extubated. No neuropsychiatric manifestations were seen post-extubation. Patient was sent to the intensive care unit (ICU) for observation and then shifted to the ward next day. Serum tryptase levels done 6 hrs after the episode showed a level of 33.5 ng/ml. Repeat serum tryptase could not be done as the patient could not afford the test.