Answer: Thanks for your question. Is your Base Hospital the Southwest? If so, this is not a message that our Base Hospital supports. While the King LT is not without its challenges, the Ontario Base Hospital Group (OBHG) MAC is not considering removing it from the Advanced Life Support Patient Care Standards. The same is true for needle cricothyrotomy and intubation.
As for your question regarding the management of acute asthma exacerbations, few studies can be found studying the use of CPAP specifically. Most studies have been hospital based and use bi-level positive airway pressure modalities (BIPAP). There is absolutely a need for further evidence in pre-hospital care as to the role of CPAP for severe asthma. As you have astutely pointed out, not every EMS system creates medical directives based upon established medical literature.
Here are some references related to the topic from:
Bauman,K Hyzy, R Noninvasive positive pressure ventilation in acute respiratory failure in adults In: UpToDate, Parsons, P(Ed), UpToDate, Waltham, MA, 2013.
Soroksky A, Stav D, Shpirer I. A pilot prospective, randomized, placebo-controlled trial of bilevel positive airway pressure in acute asthmatic attack. Chest 2003; 123:1018.
Shivaram U, Miro AM, Cash ME, et al. Cardiopulmonary responses to continuous positive airway pressure in acute asthma. J Crit Care 1993; 8:87.
Meduri GU, Cook TR, Turner RE, et al. Noninvasive positive pressure ventilation in status asthmaticus. Chest 1996; 110:767.
Patrick W, Webster K, Ludwig L, et al. Noninvasive positive-pressure ventilation in acute respiratory distress without prior chronic respiratory failure. Am J Respir Crit Care Med 1996; 153:1005.
Fernández MM, Villagrá A, Blanch L, Fernández R. Non-invasive mechanical ventilation in status asthmaticus. Intensive Care Med 2001; 27:486.
Lim WJ, Mohammed Akram R, Carson KV, et al. Non-invasive positive pressure ventilation for treatment of respiratory failure due to severe acute exacerbations of asthma. Cochrane Database Syst Rev 2012; 12:CD004360.
Nowak R, Corbridge T, Brenner B. Noninvasive ventilation. J Allergy Clin Immunol 2009; 124:S15.