Once the catheter is advanced, inflate the balloon with the appropriate volume of air. Recommended volumes may differ based on the specific brand of product used, and practitioners are encouraged to refer to product packaging for the correct volume.

The pacer may be turned on at this point with an initial setting of 80 bpm and the maximal current output (usually 20 mA). The sensitivity dial should be adjusted to the “asynchronous” setting.

Multiple methods of advancing the pacer wire have been described. In the blind approach, the catheter is advanced slowly while the ECG monitor is watched for evidence of capture. Pacer spikes will begin to be apparent and will be soon followed by a widened QRS and have a similar appearance to a left bundle branch block as the electrode contacts the wall of the right ventricle.

At this time, deflate the balloon and secure the catheter in place. Electrical current settings may be reduced until failure to capture is demonstrated to determine a threshold level. Final settings should be roughly twice the threshold value to ensure continued capture.

Ultrasound has now been advocated as an additional method for determining lead placement and capture. Verification of placement is accomplished by chest radiography demonstrating the catheter tip over the inferior border of the cardiac shadow.

Another approach uses the sensing function of the pacer to determine appropriate lead placement. The negative electrode of the pacer lead is attached via an alligator clip to any precordial lead on the patient’s chest. The remainder of the ECG leads should remain in their usual positions.

Advance the wire slowly while watching the intracardiac lead for morphology changes consistent with superior vena cava, right atrial, right ventricle, or pulmonary artery waveforms.

Engagement of the right ventricle endocardium by the pacer lead is indicated by an “injury pattern” of ST elevation. The pacer lead is then disconnected from the ECG and placed into the generator, and the generator is turned on using similar settings as above.

Finally, fluoroscopy may be used in patient-care settings where it is available.

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