Haemodynamic response to acute hypovolaemia, rapid blood volume expansion and adrenaline administration in an infant animal model.
We performed a prospective experimental animal study in seven sedated and mechanically ventilated piglets weighing 9+/-0.8 kg, to assess the haemodynamic response to acute hypovolaemia, rapid blood volume expansion and adrenaline (epinephrine) administration in an infant animal model. Withdrawal of 20 mL/kg of blood (hypovolaemia), rapid infusion of 20 mL/kg of blood (expansion) and the administration of 0.01 mg/kg of adrenaline were made in each animal. Heart rate, mean blood pressure (MBP), central venous pressure (CVP), pulmonary capillary pressure (PCP), cardiac index (CI), systemic vascular resistance index (SVRI), left ventricular contractility (Dp/dtmax), blood volume variables, including intrathoracic blood volume index (ITBI), global end-diastolic volume (GEDVI) and extravascular lung water index (ELWI). Hypovolaemia produced a significant decrease in the pressure, volume and CI variables, with an increase in SVRI and a decrease in Dp/dtmax. After expansion, all variables returned towards normal, with persistence of the SVRI increase and Dp/dtmax decrease. Changes in the blood volume variables (ITBI and GEDVI) were larger than in the pressure variables (CVP, PCP) in the case of both hypovolaemia and expansion. Adrenaline caused a slight increase in heart rate, MBP, CVP, PCP and Dp/dtmax with a greater increase in SVRI. None of the interventions led to changes in ELWI. We conclude that acute hypovolaemia produces an increase in SVRI and a decrease in Dp/dtmax that does not return fully to normal with restoration of blood volume. ITBI and GEDVI are more sensitive to changes in blood volume than CVP and PCP. Rapid blood volume expansion and adrenaline administration do not affect extravascular lung water.
López-Herce
Jesús
J
Paediatric Intensive Care Unit, Sección de Cuidados Intensivos Pediátricos, Hospital General Universitario Gregorio Marañón, Dr. Castelo, 49, 28007 Madrid, Spain. pielvi@ya.com
Rupérez
Marta
M
Sánchez
César
C
García
Cristina
C
García
Elena
E
D000208:Acute Disease; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001810:Blood Volume / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D004195:Disease Models, Animal; D004837:Epinephrine / Q000008:administration & dosage*; D015633:Extravascular Lung Water; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D020896:Hypovolemia / Q000503:physiopathology*; D011446:Prospective Studies; D012016:Reference Values; D013552:Swine; D013556:Swine, Miniature; D013815:Thermodilution / Q000379:methods
D004837:Epinephrine