Manual hyperinflation causes norepinephrine release.
OBJECTIVE
To measure hemodynamics and plasma catecholamines during manual hyperinflation (MHI) in ventilated patients.


METHODS
MHI was performed with a Mapleson "C" circuit, 2l-reservoir bag; peak inspiratory pressure was standardized to 35 mL water; and positive expiratory-end pressure of 5 mL water was administered to seven mechanically ventilated patients with septic (6) and cardiogenic (1) shock (67.2 +/- 5.2 years, Acute Physiology Assessment and Chronic Health Evaluation II score 22.1 +/- 3.1). Diastolic (DAP) and mean arterial pressure (MAP), continuous cardiac index, pulmonary artery occlusion pressure, dynamic compliance, plasma norepinephrine and epinephrine, and arterial blood gases were recorded, and systemic vascular resistance index (SVRI) and oxygenation ratio were calculated.


RESULTS
There were no significant changes in pulmonary artery occlusion pressure, mean arterial pressure, or PaO2/FiO2. There were significant increases in SVRI (P < .001), DAP (P < .001), dynamic compliance (P < .01), and plasma norepinephrine (P < .001) and a decrease in cardiac index (P < .05) after MHI.


CONCLUSIONS
The increases in DAP, SVRI, and plasma norepinephrine suggest a sympathetic vasoconstrictive response during the application of MHI.
Paratz
Jennifer
J
Department of Anaesthesiology and Critical Care, University of Queensland, Royal Brisbane Hospital, Brisbane, Australia.
Lipman
Jeffrey
J
D000368:Aged; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure / Q000502:physiology; D002851:Chromatography, High Pressure Liquid; D004837:Epinephrine / Q000097:blood; D005500:Follow-Up Studies; D006801:Humans; D009638:Norepinephrine / Q000097:blood*; D011379:Prognosis; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000379:methods*; D012131:Respiratory Insufficiency / Q000097:blood* / Q000503:physiopathology / Q000628:therapy*; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology
D015415:Biomarkers; D009638:Norepinephrine; D004837:Epinephrine