Effect of arterial blood pressure and ventilation gases on cardiac depression induced by coronary air embolism

• Published in: Journal of applied physiology (1985) Vol. 77; no. 4; p. 1896
• Main Authors: van Blankenstein, J H, Slager, C J, Soei, L K, Boersma, H, Verdouw, P D
• Format: Journal Article
• Language: English
• Published: United States 01.10.1994
• Subjects: Animals; Blood Gas Analysis; Blood Pressure - physiology; Coronary Disease - physiopathology; Coronary Vessels - physiopathology; Embolism, Air - physiopathology; Female; Injections, Intra-Arterial; Male; Myocardial Contraction; Respiration - physiology; Swine; Ventricular Pressure
• ISSN: 8750-7587
• DOI: 10.1152/jappl.1994.77.4.1896

In this study the time course of cardiac depression after selective intracoronary injection of air bubbles was investigated in six anesthetized pigs (30 +/- 2 kg) with different mixtures of ventilation gases and different mean arterial blood pressures (MAP). Air bubbles of 150 microns diam were injected into the left anterior descending coronary artery (LADCA) in a volume of 2 microliters/kg body wt. In each animal an injection of air bubbles was applied during ventilation with N2-O2 and a MAP of 77 +/- 3 mmHg (N2-O2/low pressure) or 111 +/- 3 mmHg (N2-O2/high pressure) and during ventilation with pure O2 and a MAP of 77 +/- 3 mmHg (O2/low pressure) or 110 +/- 3 mmHg (O2/high pressure). Systemic hemodynamic variables such as left ventricular pressure, its peak first derivatives, and MAP changed < 10% after injection of air bubbles. During N2-O2/low pressure, systolic segment length shortening in the LADCA region (SS-LADCA) decreased from baseline and did not return to baseline within the 10 min after injection of air bubbles. During N2-O2/high pressure and O2/low pressure, SS-LADCA was decreased between 60 and 120 s, whereas for O2/high pressure this period was from 60 to 90 s. By calculating the time integral of the deviation from baseline of SS-LADCA, it could be demonstrated that the depression of regional myocardial function was less severe during O2/high pressure and O2/low pressure than during N2-O2/low pressure. We conclude that, when coronary air embolism occurs during hypertension and during ventilation with pure O2 instead of a normal N2-O2 mixture, the resulting depression of regional myocardial function is reduced.