Recently, there has been a significant amount of discussion surrounding the effectiveness of past therapeutic practices for acute respiratory distress from congestive heart failure (CHF), and the subsequent benefit of constant positive airway pressure (CPAP) for the same. So what’s the buzz all about? Here’s what you need to know before making changes in your treatment practices:
- Constant Positive Airway Pressure:
CPAP has been held as the standard of care for assisting patients with acute respiratory distress in the hospital setting. Current advances in technology have allowed this treatment to be reasonably utilized in the prehospital arena. Previously, the CPAP devices required significant oxygen flow in excess of 100L/min, but now current models can provide CPAP of 10mmHg for 10-15minutes off of a D-cylinder (EMS portable tank). - Morphine Sulfate:
The Acute Decompenstated Heart Failure National Registry (ADHERE) conducted a study on patients admitted with CHF who received morphine and yielded important results. There was a five-fold increase in mortality (13% versus 2.4%), a five-fold increase in need for intubation and ventilation (39.7% versus 14.4%), the intensive care unit admission rate was (15% versus 3.0%), and those patients who were admitted had a prolonged hospital stay (5.6 days versus 4.2 days). Although this was an observational study, it has had a major impact on the use of morphine for CHF patients. We know that morphine causes histamine release and subsequent hypotheses have been made concluding that this may increase catecholamine release. This may be the link to the poor outcomes. Additionally, there is a lack of evidence that morphine is related to any clinically significant preload reduction. - Furosemide:
Furosemide has been on the chopping block for a while for good reason. There has been no associated vasodilatation with its administration, which is the main reason many clinicians cited for its use. The time of onset is long, about 30-120 minutes, which is too lengthy to take effect in most EMS systems. If that isn’t enough, paramedic and physician diagnosis of pulmonary edema secondary to CHF is not acceptably accurate. Error rates in the prehosptial setting range from 9-23% and the physician/hospital error rates are around 14%. Patients with infectious, drug-related or other causes of CHF do not benefit from furosemide administration and its use has been associated with even worse outcomes in these patients.
So if you haven’t made changes to your prehospital algorithms yet, you can be the one to lead the discussion with your medical director. These tools will arm you with the knowledge to change treatment practices for CHF.
References:
- Corey, Ellen. Respiratory Management. Oregon EMS Conference. 2007.
- Corey, Ellen. Improving CHF Care: A New Algorithm for Prehosptial Treatment. JEMS. April 2007.
- Wang CS, FitzGerald JM, Schulzer M., et al. Does this dyspneic patient in the emergency room have congestive heart failure? JAMA. 294(15):1944-1956, 2005.