5 year old child going for sitting craniotomy, while positioning in O.T. developed end tidal CO2- Zero mmHg, PO2- 80 mm Hg implies that :
Venous air embolism
Left lung collapse
Endotracheal tube in Oesophagus
Endotracheal tube blocked with secretions
Ans. is 'a' i.e. Venous Air embolismThe cranial sinuses have negative air pressure.So, it is possible that if the pt. is in the wrong position while operation, the sinuses may suck some air d/t their negative pressure which can cause a venous embolism.The given value for the gases can occur only in Venous air embolism.