Tuberc Respir Dis.  1999 May;46(5):645-653. 10.4046/trd.1999.46.5.645.

Factors related to the development of myocardial ischemia during mechanical ventilation

• Kim TH
• Kim YH
• Lim CM
• Kim W
• Shim TS
• Lee SD
• Kim WS
• Kim DS
• Kim WD
• Koh Y

• KMID: 2050128
• DOI: http://doi.org/10.4046/trd.1999.46.5.645

Abstract

INTRODUCTION: Although myocardial ischemia tends to occur more frequently than can be documented in ventilated patients, it has not been well studied on the factors related to the occurrence of the ischemia.
METHODS
To investigate the related factors to ischemia development,a prospective study was done in 95 cases with consecutive 73 patients who had received mechanical ventilation(MV) in MICU. In addition to 24 h holter monitoring, echocardiogram, electrolytes, cardiac enzymes, hemodynamic, and gas exchange measurements were done within 24 h after initiation of MV in 69 cases. The measurements were repeated at weaning period in 26 cases. The ischemia was defined by the ST segment changes; up-sloping depression more than 1.5 mm or down-sloping or horizontal depression more that 1.0 mm from isoelectric baseline for 80 ms following J point.
RESULTS
Twelve patients (12.6% in 95 cases) developed ischemia in total. The incidence of ischemia development showed an increased tendency in the initial 24 hr after MV (15.9%) and in patients with left-sided heart failure found by echocardiogram (18.2%) compared with that of the weaning period (3.8%) and patients without heart failure (10.9%) (P=0.12, P=0.09, in each). There were no differences in APACHE III score, baseline ECG findings, electrolytes abnormalities, use of inotropics or bronchodilators, presence of sepsis or shock, mode of ventilation, and survival rate according to the development of ischemia. Maximal heart rates and mean arterial pressure also were not different between patients with (137.2+/-30.9 /min, 82.5+/-15.9 mm Hg) and without ischemia (129.5+/-29.7 /min, 83.8+/-17.6 mm Hg).
CONCLUSION
Although the incidence of myocardial ischemia was 12.6% in total, there were no clinically predictable factors to the development of ischemia during mechanical ventilation.

Keyword

Myocardial ischemia; Mechanical ventilation; Respiratory insufficiency; Predictors

MeSH Terms

APACHE
Arterial Pressure
Bronchodilator Agents
Depression
Electrocardiography
Electrocardiography, Ambulatory
Electrolytes
Heart Failure
Heart Rate
Hemodynamics
Humans
Incidence
Ischemia
Myocardial Ischemia*
Prospective Studies
Respiration, Artificial*
Respiratory Insufficiency
Sepsis
Shock
Survival Rate
Ventilation
Weaning
Bronchodilator Agents
Electrolytes