Use of epicardial pacing wires after coronary artery bypass surgery.

OBJECTIVE

To replicate a previous study that described the incidence and characteristics of patients after coronary artery bypass graft surgery who required the use of epicardial pacing wires and to explore the reasons for epicardial pacing wire use in this patient population.

DESIGN

Ex post facto descriptive correlational.

SETTING

Cardiothoracic intensive care and step down units of a 500-bed medical center.

SUBJECTS

Convenience sample of 196 patients after coronary artery bypass graft surgery, 165 who did not use the epicardial pacing wires and 31 who used the epicardial pacing wires to augment cardiac output, diagnose dysrhythmias, suppress dysrhythmias, or treat heart block. Patients receiving other surgical techniques in combination with coronary artery bypass graft surgery were not included.

PROCEDURE

Recording of demographic and clinical data for all of the sample population, with additional data collected when the epicardial pacing wires were used.

DATA ANALYSIS

Independent t test and chi-square analysis were used to determine significance between the means and frequencies in the variables of the patients who used the epicardial pacing wires and those who did not. The significance level was set at 0.05.

RESULTS

There were no statistically significant differences between the groups in terms of age or previous or recent myocardial infarction, which was opposite of the replicated study's findings. A statistically significant difference (p < 0.001) was found between the groups for the use of inotropic support, which was also opposite of the findings of that study. The group requiring epicardial pacing wire utilization demonstrated a greater need for diuretics in the preoperative phase than those who did not (p < 0.01), as well as a higher use of digitalis therapy before surgery (p < 0.01). Additionally, those who were paced experienced a greater cardiac output (p = 0.013) and cardiac index (p = 0.018) after pacing was initiated.

CONCLUSIONS

The variation in findings between this study and the one replicated may be the result of variations in the patient populations, treatment practices, or preoperative condition. Replication of this study at a future date may reveal variables not identified here.