Intravenous dihydropyridine calcium channel blockers can quietly worsen oxygenation by blunting hypoxic pulmonary vasoconstriction. In this episode, we break down the bedside mechanism, which agents are implicated, who’s at highest risk (post-op atelectasis, obesity, pneumonia, focal ARDS, COPD), how soon it happens, and exactly what to do.
The Vasopressor & Inotrope Handbook
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Citations:
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Lumb AB, Slinger P. Hypoxic pulmonary vasoconstriction: physiology and anesthetic implications. Anesthesiology. 2015 Apr;122(4):932-46. doi: 10.1097/ALN.0000000000000569. PMID: 25587641.
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Simonneau G, Escourrou P, Duroux P, Lockhart A. Inhibition of hypoxic pulmonary vasoconstriction by nifedipine. N Engl J Med. 1981 Jun 25;304(26):1582-5. doi: 10.1056/NEJM198106253042606. PMID: 7231503.