Take My Breath Away! Evaluation of Shortness of Breath in the ED
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Is it chest pain or epigastric pain? I can’t quite put my finger on it….
There are many chief complaints in the emergency department that can be less than satisfying (*cough* abdominal pain *cough*). Sometimes such patients end up having a completely benign examination, no significant risk factors found on history, and an encounter that leaves you shrugging your shoulders and telling the patient “bellies will do that sometimes, we don’t always find out why.”
Of course, this is all anecdotal, but the chief complaint on this month’s episode seems to have a more consistent presence of pathology with a wide range of severity. With such heterogeneous pathophysiology we turn to the mind of Dr. Stewart Wright to discuss the initial approach to the patient with shortness of breath (SOB).
Some highlights from his episode include:
- Perhaps the most important part of your physical exam is your view of the patient from across the room. Take a moment to really watch how the patient is breathing, what rate, with what degree of effort, etc.
- Adopt the A-B-C approach when assessing shortness of breath to prioritize immediate life threats. Assess for airway compromise first, if not present, move on to breathing and circulation as potential causes for SOB.
- Utilize past medical history and chart review to help guide your differential, but be careful not to succumb to anchoring
- Early review of vitals is key, including a true respiratory rate and SpO2. Begin oxygen therapy during your assessment if it is indicated, start big and wean down once you reach a safe oxygenation status.
- (And if I may add my own suggestion, again anecdotal, adopt early use of ultrasound in your assessment. In addition to looking for pneumothorax, pulmonary edema and cardiac contractility, I have been lucky to stumble upon several unexpected pericardial effusions when my exam hadn’t revealed any cardiopulmonary findings.)
I find your lack of wheezing disturbing...
During discussion regarding therapeutics towards the end of the episode the topic of non-invasive positive pressure ventilation (NIPPV) is touched upon briefly, namely as a temporizing measure for reversible causes of shortness of breath such as acute pulmonary edema and COPD. In regards to these two pathologies, utilization of NIPPV has borne out as a successful therapy in decreasing work of breathing and avoiding intubation and all the complications that may ensue with that more invasive approach. During some review on the topic I came across three other instances where this therapy has been used successfully in the ICU that may translate to beneficial care in the emergency department. (1)
NIPPV in Chest Trauma?
Chiumello, D., et al. (2013) conducted a systematic review and meta-analysis of 4 randomized controlled trials and 6 observational studies looking at the use of NIPPV in chest trauma patients, analyzing whether NIPPV has any effect on mortality, intubation rate, and length of stay in hospital as compared to standard therapy alone (analgesics, supplemental O2, pulmonary toilet, etc). (2) The physiology and theory behind this makes sense; chest trauma patients (particularly elderly) with broken ribs, lung contusions, and all other manner of pain-causing injuries to the chest tend to have difficulty in maintaining alveolar recruitment, predisposing for infection and difficulty with oxygenation and ventilation, and as such, one would expect the addition of positive pressure to the mix to be beneficial. The results of the analysis seem to support this hypothesis. Of the 10 studies included, five reported regarding mortality benefit with pooled data showing 3/101 (3.0%) deaths in the NIPPV patients as compared to 27/118 (22.9%) in the control group, estimating the pooled RR to be that of 0.26 ((95 % confidence interval 0.09 to 0.71, p = 0.003). The population was also found to have similar benefit in intubation rates and hospital length of stay. This certainly doesn’t mean you should be putting every person with rib fractures on CPAP, and the majority of benefit would apply more over the long term during a hospitalization, however, it is a good idea to have in mind for early initiation, particularly if such a patient will be boarding with you for a while before a bed becomes available upstairs.
NIPPV in the Immunosuppressed?
Another study published in 2001 found a benefit to NIPPV in immunosuppressed patients. (3) As a prospective, randomized trial, this study evaluated 52 patients with immunosuppression (the largest subset being patients with hematologic malignancies with neutropenia) presenting with pulmonary infiltrates, fever, and early stages of hypoxemic respiratory failure. Patients were randomized to either conventional therapy (venturi mask) or conventional therapy plus intermittent NIPPV (at least 45 minutes performed every 3 hours). Patients in the NIPPV group were found to have an improvement in rate of intubation (12/26 or 46% vs 20/26 or 77% with a P=0.03) and rate of death in the ICU (38% vs 69% P=0.03). Although limited by lack of blinding and relatively small sample size, the benefit to mortality and intubation rates again makes physiologic sense. Furthermore, it’s interesting to note the improved outcomes in these patients with fever and pulmonary infiltrates as compared to the questionable benefit to traditional patients with community acquired pneumonia. One could postulate simply that as far as complications of intubation go, the stakes are much higher with this immunosuppressed population, a fact that warrants thought when such a patient presents to the emergency department that needs that extra bit of help to breathe.
The Role of NIPPV in Palliative Care
Lastly, I encountered a review of NIPPV as it pertains to palliative care (which frankly doesn’t get the play it deserves in emergency medicine). (4) Suggested benefits to this population include alleviation of dyspnea, preserved communication, and possible bridging to baseline respiratory status without intubation during reversible pathology. Though the discussion in this paper focuses on the use of NIPPV in the ICU, and much of the topic continues to be debated, what I found to be concrete, helpful, and certainly applicable in the ED was this: if the patient is suffering and anxious due to their work of breathing and if the patient is able to cooperate with NIPPV and receives relief of their dyspnea by using it, then it is by all means indicated.
References
- Mas, Arantxa, and Josep Masip. "Noninvasive ventilation in acute respiratory failure." International journal of chronic obstructive pulmonary disease 9 (2014): 837.
- Chiumello, D., et al. "Noninvasive ventilation in chest trauma: systematic review and meta-analysis." Intensive care medicine 39.7 (2013): 1171-1180.
- Hilbert, Gilles, et al. "Noninvasive ventilation in immunosuppressed patients with pulmonary infiltrates, fever, and acute respiratory failure." New England Journal of Medicine 344.7 (2001): 481-487.
- Azoulay, Élie, et al. "Palliative noninvasive ventilation in patients with acute respiratory failure." Intensive care medicine 37.8 (2011): 1250-1257.
