Trigeminocardiac reflex may mimic symptoms of air embolism!

Sir,

I read with interest the article by El-Zenati et al.[1] Air embolism during skull pin removal is not new and has been reported by us in 2008.[2] The incident in our patient had been documented and confirmed by transesophageal echocardiography (TEE) also. The occurrence of hypotension and bradycardia could have possibly been due to the trigeminocardiac reflex (TCR).[3] Simultaneously, reduction of end-tidal carbon dioxide could be secondary to severe hypotension. The TCR could be a better explanation in this patient as the authors fail to show evidence for the occurrence of air embolism. Air was neither aspirated or visualized using TEE. Moreover, the clinical condition improved after a bolus of 30 mg ephedrine and fluids, suggesting that the fall in end-tidal carbon dioxide could be due to systemic hypotension. The possibility of the TCR cannot be overlooked as the authors have not explained the exact sequence of events in the occurrence of air embolism.