Open AccessCardiovascular effects of intravenous colforsin in normal and acute respiratory acidosis canine models: A dose-response study
Author(s) -
Takaharu Itami,
Kiwamu Hanazono,
Norihiko Oyama,
Tadashi Sano,
Kohei Makita,
Kazuto Yamashita
Publication year - 2019
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0213414
Subject(s) - acidosis , medicine , hypercapnia , dobutamine , anesthesia , respiratory acidosis , metabolic acidosis , base excess , isoflurane , hemodynamics
In acidosis, catecholamines are attenuated, and higher doses are often required to improve cardiovascular function. Colforsin activates adenylate cyclase in cardiomyocytes without beta-adrenoceptor. Here, six beagles were administered colforsin or dobutamine four times during eucapnia (partial pressure of arterial carbon dioxide 35–40 mm Hg; normal) and hypercapnia (ibid 90–110 mm Hg; acidosis) conditions. The latter was induced by CO 2 inhalation. Anesthesia was induced with propofol and maintained with isoflurane. Cardiovascular function was measured by thermodilution and a Swan-Ganz catheter at baseline and 60 min after 0.3 μg/kg/min (low), 0.6 μg/kg/min (middle), and 1.2 μg/kg/min (high) colforsin administration. The median pH was 7.38 [range 7.33–7.42] and 7.01 [range 6.96–7.08] at baseline in the Normal and Acidosis conditions, respectively. Endogenous adrenaline and noradrenaline levels at baseline were significantly ( P < 0.05) higher in the Acidosis than in the Normal condition. Colforsin induced cardiovascular effects similar to those caused by dobutamine. Colforsin increased cardiac output in the Normal condition (baseline: 3.9 ± 0.2 L/kg/m 2 [mean ± standard error], low: 5.2 ± 0.4 L/kg/min 2 , middle: 7.0 ± 0.4 L/kg/m 2 , high: 9.4 ± 0.2 L/kg/m 2 ; P < 0.001) and Acidosis condition (baseline: 6.1 ± 0.3 L/kg/m 2 , low: 6.2 ± 0.2 L/kg/m 2 , middle: 7.2 ± 0.2 L/kg/m 2 , high: 8.3 ± 0.2 L/kg/m 2 ; P < 0.001). Colforsin significantly increased heart rate and decreased systemic vascular resistance compared to values at baseline. Both drugs increased pulmonary artery pressure, but colforsin (high: 13.3 ± 0.6 mmHg in Normal and 20.1 ± 0.2 mmHg in Acidosis) may have lower clinical impact on the pulmonary artery than dobutamine (high: 19.7 ± 0.6 in Normal and 26.7 ± 0.5 in Acidosis). Interaction between both drugs and experimental conditions was observed in terms of cardiovascular function, which were similarly attenuated with colforsin and dobutamine under acute respiratory acidosis.