Hypercapnia effects

Q: Permissive hypercapnia tends to induce? (select one) 

A) Vasoconstriction 
B) vasodilation


Answer: B

Despite augmentation of sympathomimetic output permissive hypercapnia tends to induce systemic vasodilation, particularly in hypovolemic patients. To maintain adequate hemodynamic, permissive hypercapnia may require both beta blocker to counter tachycardia and adequate volume replacement to counter vasodilation.

#hemodynamic
#ventilator
#ARDS
#pulmonary
#acid-base


References:

1. Kavanagh BP, Laffey JG. Hypercapnia: permissive and therapeutic. Minerva Anestesiol 2006; 72:567. 

2. Nahurn, A, Marini, JJ. Alternatives to conventional mechanical ventilation in acute respiratory failure. Curr Pulmonol 1994; 15:157.