"First off, put in a big tube! Consider an awake intubation with ketamine sedation, RSI can be dangerous in these patients. Don't be shy with the epi! Gradually titrate up the peep until you match the patient's internal auto-peep which will essentially help stent open the airways producing less bronchoconstriction allowing for better airflow. Rapid inspiration, long expiration. Don't be so afraid about permissive hypercapnea, they are intubated, let them auto-sedate with CO2, just don't let their pH get too low (keep above 7.1-7.2). Ketamine drip for sedation. Just a few thoughts."
I would agree with most of the above, however...
1) These patients don't need any PEEP. As mentioned, they are already auto-peeping, which is their issue to begin with - they can't get the air out. so in a sedated and/or paralyzed pt, there's really no reason to give them PEEP - I would say the only reason to give PEEP is if they are awake, bc with zero PEEP they will feel/be sucking through a tiny tiny straw with no help and I imagine that would feel miserable
2)Permissive hypercapnia is necessary so that these pt's can have low enough tidal volumes & long enough expiratory times to slowly exhale their retained air. However hypercapnia is not a pleasant or 'auto sedating' feeling - it is very uncomfortable which is why many hypercapnic pt's are anxious, become agitated and delirious, rip off their bipap masks, and keep twitching. sure, once the CO2 reaches critical levels, they basically become obtunded/comatose, but we shouldn't be aiming this high for permissive hypercapnia - i would say more like a co2 in the 50s-80s (depending on pt and where they live), which I would venture for most people would be enough to cause them to feel agitated rather than sedated.
I like the judicious use of ketamine. I think the ketofol drips are slowly making their way in, although not sure of the literature behind it.
recently had a bad asthmatic (intubated previously 6 times) who came in, minor initially, got some nebs/steroids (didn't even give mag initially she looked/sounded so good, and didn't feel she warranted an IV), then slowly got worse - placed on cont nebs, then on bipap with inline nebs, got mag, kept getting worse, was tripoding, stating she thought she need to be tubed. we gave her heliox and epi, no improvement. at that point we were going to tube her so we decided to try a smaller dose of ketamine to see if we could get any improvement at all to prevent intubating - gave her 0.4 mg/kg which didn't help (made her a bit less anxious though), so tubed her anyway - any of you guys ever try lower dose ketamine as a final salvage?
one final thing - bolus these patients with fluids if you're about to tube them as the change from negative pressure to positive pressure ventilation, combined with the autoPEEPing and loss of sympathetic drive during RSI, is going to cause a quick reversal in hemodynamics as their preload plummets. push dose epi or phenyl is a good option here peri/post intubation as well.
