Kosowsky et al. CPAP FOR PRESUMED PULMONARY EDEMA
195
atmosphere in which any concerns would have been
freely raised.
trials are needed to address the overall utility and
cost–effectiveness of CPAP systems in the prehospital
setting.
As our study was designed, the paramedics were
taught criteria on which to base the use of CPAP, but
individual decisions were left to their discretion.
Analysis of the run sheets demonstrated that all
patients who received CPAP met the basic indications
set forth with regard to respiratory rate, work of
breathing, and presence of rales. However, four
patients were given CPAP in spite of potential con-
traindications. Although no complication resulted
from the use of CPAP in these instances, the inclusion
of these patients (three of four of whom required ETI)
adversely affected the overall success rate. Future
efforts should focus attention on the important con-
traindications to CPAP.
The success of CPAP therapy depends on appropri-
ate patient selection, and caution must be taken to
avoid any intervention that could be deleterious in the
prehospital setting. For patients with compromised
upper airway function or significantly altered level of
consciousness, ETI should remain the treatment of
choice. Also, patients with cardiac arrest, unstable car-
diac rhythms, or cardiogenic shock are generally not
considered to be candidates for CPAP and have been
excluded from major clinical trials.2–4 Patients with
excessive secretions are poor candidates for CPAP
because there is no direct access for removal of secre-
tions, and frequent expectoration interferes with the
maintenance of positive airway pressure. Finally, in
the setting of severe myocardial ischemia or infarc-
tion, ETI with full ventilatory support may be prefer-
able to CPAP, because the work of breathing increas-
es myocardial oxygen demand.5
On the basis of this case series alone, CPAP cannot
be recommended for general use in the prehospital
setting. Larger, controlled clinical trials are required to
demonstrate not only safety and efficacy, but also
cost–effectiveness. For example, the expense of equip-
ment, maintenance, training, and quality assurance
may end up being prohibitive for some EMS systems.
Prehospital CPAP may prove to be most useful in
EMS systems in which transport times are long and
personnel with advanced airway skills are not readily
available. However, at present prehospital CPAP
remains an investigational therapy that should not be
routinely implemented outside the context of an IRB-
approved research study.
The authors are grateful to the paramedics of the City of Cincinnati
whose dedication to patient care made this study possible. They
also acknowledge the assistance of Melissa Gasaway, Michael
Ottaway, and Todd J. Crocco, MD, for their time and effort over the
course of the study.
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CONCLUSIONS
This case series suggests that for patients with respira-
tory failure and presumed pulmonary edema, the pre-
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need for ETI. Future work should focus on helping
paramedics to identify patients most likely to benefit
from early application of CPAP. Controlled clinical
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