A 62-year old male is admitted through the Emergency Department (ED) with a fifty-hour history of worsening sore throat, cough, and increased work of breathing.
(WOB) Samples have been collected for Covid-19 and an arterial blood gas was drawn with the following results:
- FI02 = .40 via venturi mask
- Patient respiratory frequency = 48/minute
- pH = 7.28
- paC02 = 52mmHg
- pa02 = 57mmHg
- Sa02 = 86%
Although somewhat lethargic, the patient is awake and cooperative. Based upon the signs of impending respiratory collapse, the options of intubation and mechanical ventilation vs. a trial using positive end-expiratory pressure via silicon elastomer mask were discussed. It was agreed to proceed with the less invasive CPAP trial.
After providing detailed instructions to the patient, 10cmH20 of CPAP (FI02 = .40) was administered via the mask secured in place by a standard anesthesia harness. The respiratory frequency dropped from 48/minute to 39/minute. The patient indicated his WOB felt improved. After 20 minutes, a repeat ABG was drawn with the following results:
- FI02 = .40 (high-flow CPAP system)
- Patient respiratory frequency = 39/minute
- pH = 7.34
- paC02 = 39mmHg
- pa02 = 170mmHg
- Sa02 = 91%
This patient presented in early respiratory failure apparently due to COVID-19 infection. (Lab findings returned positive for the virus.) Although intubation and mechanical ventilation would happen often in a variety of clinical settings, the option of using CPAP via tight-fitting face mask yielded significant improvement in not only oxygenation status but improved the efficiency of the patient’s own ventilatory status.
This report is simply intended to remind practitioners that therapeutic end-pressure does not have to be administered via an artificial airway in conjunction with unnecessary augmented tidal ventilation.
All practitioners making these decisions should pay careful attention to the patient’s LOC and especially their ability to protect their airway. These patients require careful monitoring, preferably in a critical care setting.