Hemorrhagic shock complicated by chronic ethanolism

Area of Science:

• Cardiovascular Physiology
• Toxicology
• Trauma Research

Background:

• Chronic ethanolism is prevalent and impacts physiological responses.
• Hemorrhagic shock (HS) poses significant challenges to cardiovascular function.
• Understanding ethanol's effects on shock response is crucial for trauma care.

Purpose of the Study:

• To investigate the impact of chronic ethanolism on dogs' responses to hemorrhagic shock (HS).
• To assess cardiocirculatory function and myocardial oxygen dynamics in ethanol-treated dogs during shock.

Main Methods:

• Dogs were chronically fed ethanol (3 g/kg) for 3 or 9 months, or a control diet.
• Animals underwent induced HS (mean arterial pressure of 30 mmHg for 2 hours) or observation.
• Cardiovascular parameters, blood gases, hematocrit, and myocardial function were measured.

Main Results:

• Chronic ethanolism altered baseline cardiocirculatory function (e.g., increased MAP, lactate; decreased cardiac output).
• HS impaired cardiovascular performance similarly in both ethanol-treated and control groups.
• Ethanol-treated dogs exhibited higher coronary blood flow, oxygen delivery, and consumption during shock.
• Myocardial calcium content was elevated in ethanol-treated dogs, suggesting a role in contractile dysfunction.

Conclusions:

• Chronic ethanolism affects baseline cardiovascular function and alters the response to HS.
• Ethanol consumption may increase myocardial oxygen supply during shock, but contractile dysfunction persists.
• Altered calcium homeostasis is implicated in ethanol-induced cardiac contractile dysfunction in trauma subjects.