Review of: Singer AJ, Emerman C, Char DM, et al. "Bronchodilator therapy in acute decompensated heart failure patients without a history of chronic obstructive pulmonary disease." Annals of Emergency Medicine. 51(1):25–34, 2008.
This study examined what occurred to patients who were given bronchodilators for their complaint of dyspnea when they were ultimately diagnosed with congestive heart failure (CHF) instead of chronic obstructive pulmonary disease (COPD). The research was extracted from the multi-center Acute Decompensated Heart Failure National Registry. Of the 10,978 patients enrolled, 7,299 (66.5%) didn't have a history of COPD. Bronchodilators were administered by EMS or in the emergency department (ED) to 2,316 (21%) of the 10,978 patients.
Bronchodilators were more likely to be given to patients with a history of COPD than those without COPD (34.7% vs. 14.3%). However, patients without a history of COPD were significantly more likely to receive IV vasodilators and mechanical ventilation, including BiPAP, than those with COPD. Additionally, patients without COPD received these interventions more rapidly than those with COPD. No difference in hospital mortality existed between the groups.
They discovered patients without COPD (those with CHF as the primary condition) were more likely to have lower oxygen saturations, and higher blood pressure and pulse rates.
The authors concluded use of bronchodilators reflected a greater need for aggressive interventions and monitoring. They raised but were unable to answer the question as to whether bronchodilators worsened the patients' condition or merely may be a marker of more severe disease.
This is another study substantiating the axiom "All that wheezes is not asthma." Several studies have shown no direct adverse effect of bronchodilators inadvertently administered to patients with CHF while some have shown worsening of myocardial infarction. This study cannot draw a cause and effect between bronchodilator administration and worse outcomes in CHF. However, it does highlight some very interesting aspects of how to approach the patient with dyspnea.
First, if the patient does not have a diagnosis of COPD and is short of breath, they're more likely to be suffering from CHF. I tell my medics that the diabetic with shortness of breath is in failure until proven otherwise.
Additionally, you should use the presence of lower oxygen saturations and elevated blood pressures and pulse rates to help differentiate the patient who has a history of COPD but is in fact in failure. The CHF patient is in a high adrenergic state and often presents hypertensive and tachycardic. This is the body's attempt to improve perfusion.
And finally, administering bronchodilators doesn't treat the underlying cause of heart failure, which is cardiac dysfunction. Instead of wasting time setting up nebulizers, your patient will benefit more from early application of CPAP and, if possible, the early administration of nitrates either sublingually or intravenously.