Cardiocirculatory function in the intoxicated shocked dog: acid base derangements

Area of Science:

• Cardiovascular Physiology
• Toxicology
• Shock Pathophysiology

Background:

• Ethanol consumption can affect physiological functions.
• Hemorrhagic shock leads to significant hemodynamic and metabolic disturbances.
• The combined effects of ethanol and shock on cardiac performance are not fully understood.

Purpose of the Study:

• To investigate the impact of acute ethanol consumption on cardiac performance and regional blood flow, alone and combined with hemorrhagic shock in canines.
• To evaluate the role of acid-base derangements in ethanol-induced shock pathophysiology.
• To assess the efficacy of acid-base correction in mitigating negative effects.

Main Methods:

• Canine model subjected to acute ethanol administration or saline control.
• Hemorrhagic shock induced by bleeding to a mean arterial blood pressure of 30-35 mmHg for 2 hours.
• Subgroups of alcoholic dogs received either continuous acid-base correction or no correction.
• Cardiac performance and regional blood flows were monitored.

Main Results:

• Ethanol alone did not depress cardiac function or regional blood flow in normovolemic dogs, despite acidosis.
• Hemorrhagic shock similarly impaired cardiac function and perfusion in both ethanol-intoxicated and non-intoxicated dogs.
• Acid-base correction in shocked, intoxicated dogs improved subendocardial perfusion and left ventricular performance compared to uncorrected dogs.

Conclusions:

• Acute ethanolism exacerbates acidosis during hemorrhagic shock, likely due to impaired respiratory compensation.
• Acidosis plays a causative role in reduced cardiac performance following shock resuscitation in intoxicated dogs.
• Acid-base correction is a viable strategy to improve outcomes in ethanol-associated shock.