A ground ALS ambulance staffed with an EMT-Basic and a paramedic responds to a shortness of breath call. The crew is informed that the patient is a 55-year-old male with a history of COPD and CHF. On arrival, a 150 kg patient is found awake and interactive but in severe respiratory distress, stating in one word bursts that he cannot breathe. Audible noisy, wet breathing is noted on auscultation and the patient’s medication history is significant for loop diuretics and hypertensive medications. His vital signs include a saturation of 82%, B/P 224/160, pulse 140, respirations 44 and ETCO2 of 70mm Hg. His wife informs you that he has been admitted to the ICU four times in the past year and the last few times this has happened he’s needed to be put on a breathing machine.
This ground agency does not carry any neuromuscular blockades and the paramedic is concerned about controlling the patient’s airway if he becomes unstable. The options for controlling the airway of a conscious or semi-conscious patient can be difficult, especially without the aid of rapid sequence intubating drugs. What is the safest course of action for this ground unit to proceed in controlling this patient’s airway?
Immediate simple interventions include sitting the patient upright and placing high-flow oxygen with an non-rebreather mask, which may require some coaching in the hypoxemic, hypercarbic and distressed patient. Just as a reminder, standard non-rebreather masks deliver only 70% oxygen—at best—but at this point we’re aiming for a saturation of about 90% given the patient’s severe underlying COPD and hypercarbia, which suggest he may have a hypoxic ventilatory drive. A nice detail would be to place a nasal cannula under the oxygen mask to use later to supplement oxygen delivery during non-invasive ventilation or intubation. It is always important to let the patient assume the position most comfortable to them, as they are attempting to breathe, even if it looks unorthodox bringing a patient into the emergency room straddling a stretcher backward!
Many things are likely happening simultaneously but the next step may be to place the patient on CPAP, which should improve saturations and respiratory distress, regardless of whether this turns out to be more CHF, COPD or pneumonia. If the assessment supports a CHF exacerbation as the primary pathology, then nitrates can have a very rapid impact. Some protocols may also call for diuretics and morphine, though many systems are phasing these CHF treatments out in lieu of CPAP and aggressive nitrate therapy.
Most patients will have markedly improved at this point. If the crew is unable to support the patient with these interventions and he continues to deteriorate, the patient will require assisted ventilation with PEEP (positive end-expiratory pressure). If transport times are long, or the patient does not tolerate or improve with assisted ventilation, then intubation should be performed. In this particular case a very difficult intubation is predicted based upon his obesity and extremely limited reserve. In systems with drug-facilitated intubation protocols this patient may be a candidate for rapid sequence intubation, but the chance of a failed airway or the patient coding during the procedure is high. Alternatives include nasal intubation and gentle oral intubation. The drawbacks of nasal intubation in this patient are exacerbating hypoxemia during the procedure, stimulating bronchospasm and the smaller tube sizes, which can make ventilating patients with this kind of lung disease very difficult. Gentle oral intubation would require a completely obtunded patient and still runs the risk of stimulating vomiting. In the end, weighing the risk and benefits, it appears that non-invasive airway management is the best option unless one’s hand is forced by deterioration combined with long transport times.