The effect of volume infusion on dead space in mechanically ventilated patients with severe asthma.
Mechanical ventilation of patients with severe asthma is associated with elevated airway pressures that may contribute to increased physiologic dead space. To our knowledge, no previous reports have considered the effect of intravascular volume status on dead space fraction. We herein describe three patients whose dead space decreased by a mean of 4.2% in response to intravascular volume expansion with 250 or 500 mL of normal saline solution administered as part of their routine treatment. No significant changes in CO2 production, minute volume, or airway pressures occurred over the time interval. We conclude with a brief discussion of potential mechanisms to explain these findings and their potential clinical application.
Manthous
C A
CA
Pulmonary and Critical Care Division, Bridgeport Hospital and Yale University School of Medicine, Conn, USA.
Goulding
P
P
D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000503:physiopathology / Q000628:therapy*; D002245:Carbon Dioxide / Q000097:blood / Q000378:metabolism; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D006935:Hypercapnia / Q000628:therapy; D010952:Plasma Substitutes / Q000627:therapeutic use*; D011175:Positive-Pressure Respiration; D011312:Pressure; D012123:Pulmonary Ventilation; D012119:Respiration / Q000187:drug effects; D012121:Respiration, Artificial; D012126:Respiratory Dead Space / Q000187:drug effects*; D012131:Respiratory Insufficiency / Q000628:therapy; D012965:Sodium Chloride / Q000627:therapeutic use; D013224:Status Asthmaticus / Q000628:therapy
D010952:Plasma Substitutes; D002245:Carbon Dioxide; D012965:Sodium Chloride