Hypoxia in drowning

Q: What is the recommended oxygen saturation in a post drowning patient? 

 A) 88% 
B) 90% 
C) 92% 
D) 94% 
E) 100%

Answer: D (94%)

In post drowning patients higher than normal pulse-ox saturation or PO2 (60 mmHg) is recommended as tissue hypoxia is the major cause of the fatality. While managing hypoxia in post drowning patient, at least three points should be kept in mind

• There should be a low threshold for intubation and beside hypoxia, even mild to moderate hypercarbia requires intubation at PCO2 50 mmHg (some even suggests more than 45 mm Hg)
• In comparison to other patients, the orogastric tube is almost mandatory in post drowning patients as gastric distension may hamper ventilation.
• Positive pressure ventilation (PPV) with higher PEEP is recommended but it comes with its own price in post drowning patients, as the line of demarcation between hypotension due to PPV and therapeutic oxygenation is very thin, and requires particular monitoring post intubation.

Reference:

Layon AJ, Modell JH. Drowning: Update 2009. Anesthesiology 2009; 110:1390.