A 29 year female is being operated for removal of mass from cerebellum. When the patient was given sitting position, suddenly the patient saturation became 60% and ETCO2 became zero. All of the following may be the causes for this presentation, except:
|D||Secretion in tube|
a. In this patient ETCO2 has fallen during positioning which can occur in case of accidental extubation tube kinking, obstruction and tube disconnection.
b. Other possibility of falling ETCO2 in posterior fossa surgery is of venous air embolism but this will not happen at the commencement of surgery- This complication will occur only when dura is opened i.e., after some time of commencement of surgery and ETCO2 becoming zero is rare in embolism