Aspiration on Emergence

 

A 48 yo woman had had a hysteroscopy and D and C and was having her legs taken out of the stirrups when yellow fluid poured out of her mouth around the LMA.

The anaesthetist did the following:

•        called to the nursing staff for assistance        
•        asked that the legs be taken out of lithotomy
•        requested the sucker
•        tipped the table head down 20 degrees
•        sucked out the pharynx
•        turned the O2 on to 8 L/min
•        attempted to bag ventilate the patient via the LMA
•        removed the LMA

 

It was not possible to bag and mask ventilate the patient because of presumed laryngospasm. By this stage the O2 saturation was 85% and falling rapidly. The pulse was 125, there was no CO2 trace and the BP was 160/90.

The anaesthetist then called for suxamethonium to be drawn up and asked for the patient to turned onto her left side. Despite positive pressure ventilation with PEEP it was not possible to ventilate  the patient at all.

Next the anaesthetist:

•   looked at the monitor – O2 sat 68%
•   gave 20mg suxamethonium IV
•   performed laryngoscopy and sucked out the pharynx under vision
•   gently applied IPPV and was able to achieve some ventilation

 

The saturation slowly rose to 80%. The patient started spontaneous respiration  with coughing interspersed with periods of breath-holding. The patient received 100% O2 via a mask attached to the circle circuit with the expiratory valve tightened to achieve some PEEP. Widespread wheezes and course crepitations could be heard throughout both lungfields.

 

As the saturation fell again over the next few minutes towards 70, the patient was given propofol 150mg and suxamethonium 100mg, intubated and ventilated. The O2 saturation improved to the low 80’s. Morphine and midazolam were used to sedate the patient and a CXR performed which showed patchy consolidation bi-laterally. The patient was transferred to ICU.

 

Comment 1

 I think this anaesthetist performed well and carried out the required resuscitation in an appropriate manner. One thing I have found is that it is sometimes more difficult to manage such patients on their sides (particularly for intubation) and I consider it is probably too late to stop bilateral aspiration after the initial regurgitation event. So I would probably have left this patient in the supine moderately head-down position.

 

Question 1

Is there a role for sucking out the trachea with a Y-suction catheter after paralysis and before instituting  IPPV in an effort to reduce pulmonary spread of aspirated material?

 

Question 2

At what level of O2 sat should one intervene with paralysis and IPPV? Allowing the sat to fall lower knowing the patient's will eventually take a breath will avoid the potential problems of suxamethonium and possibly spreading aspirated material through the lungs.