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Review
. 2024 Apr;40(2):235-253.
doi: 10.1016/j.ccc.2024.01.002. Epub 2024 Jan 25.

Diagnosis and Management of Acute Respiratory Failure

Madeline Lagina  1 , Thomas S Valley  2
Affiliations
Review

Diagnosis and Management of Acute Respiratory Failure

Madeline Lagina et al. Crit Care Clin. 2024 Apr.

Abstract

Acute hypoxemic respiratory failure is defined by Pao2 less than 60 mm Hg or SaO2 less than 88% and may result from V/Q mismatch, shunt, hypoventilation, diffusion limitation, or low inspired oxygen tension. Acute hypercapnic respiratory failure is defined by Paco2 ≥ 45 mm Hg and pH less than 7.35 and may result from alveolar hypoventilation, increased fraction of dead space, or increased production of carbon dioxide. Early diagnostic maneuvers, such as measurement of SpO2 and arterial blood gas, can differentiate the type of respiratory failure and guide next steps in evaluation and management.

Keywords: Diagnosis; Hypercapnia; Hypoxemia; Management; Respiratory failure.

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Conflict of interest statement

Disclosure The authors have nothing to disclose. Funding provided through NHLBI K23 HL140165 and NHLBI R01 HL157361. This manuscript does not necessarily represent the view of the US Government or the Department of Veterans Affairs.

Figures

Figure 1:
Figure 1:
The alveolar gas equation
Figure 2:
Figure 2:
Calculation of the normal A-a gradient
Figure 3:
Figure 3:
Age-adjusted A-a gradient equation
Figure 4:
Figure 4:
Diagnosis and early management of respiratory failure
See this image and copyright information in PMC

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