Acute severe community-acquired pneumonia: respiratory failure and ventilator management

^{[2] [6] [7] [11] [17] [18] [20] [1] [2] [3] [5] [8] [14] [15] [17] [20] [21]}

Meet the patient

A 66-year-old woman (BMI 31) is brought to the ED by her daughter. Two days of fever, rigors and progressive breathlessness. RR 34, SpO2 86% on a non-rebreather at 15 L/min, BP 102/64, HR 118, GCS 15, temperature 38.7°C. CXR: multilobar consolidation. ABG (on 15 L/min NRB): pH 7.32, PaCO2 34, PaO2 56, lactate 2.4. She is alert but using every accessory muscle, and her trachea dips in on inspiration. The registrar asks: HFNC, NIV or intubation now?^[1]

The question that will define her ICU stay is not whether she has pneumonia — she does, and the CXR confirms it. It is the trajectory: is the non-invasive support holding, or is she silently crossing from V/Q mismatch (oxygen-responsive) to shunt (oxygen-refractory)? Intubate for the trajectory, not the number.^[1] Formal severity tools frame her risk: CURB-65 stratifies 30-day mortality (score 3, 17%; score 4, 41.5%; score 5, 57%), while SMART-COP is built to predict the need for intensive respiratory or vasopressor support — a score of 3 or more identified 92% of patients who needed it. She is heading for the ICU either way.^[12][13]

References25ShowHide

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