Indications

• Symptomatic sinus bradycardia (after atropine, +/- dopamine/epinephrine, and transcutaneous pacing have failed)
• Mobitz type II second degree AV block
• Complete heart block
• Beta blocker or calcium channel blocker overdose

Preparation 

• Patient positioning: supine/Trendelenburg
• 6 French Cordis (“percutaneous sheath introducer kit”)
• Swan Ganz/Bipolar pacing catheter
• Pacer generator (“temporary pacemaker”)
• Nonsterile connecting cable (within pacer generator case in inside sleeve)
• Ultrasound + sterile probe cover

Supplies and room 9 location

Pacer generator—initial settings 

• Turn on
• Rate—80 bpm, rate at which patient will be transvenously paced, at least 20 bpm over the intrinsic rate
• Output—20 mA, electrical output of pacer with every paced beat, decrease until patient has both mechanical (palpating patient’s pulse) and electrical capture
• Sensitivity—3 mV, pacer’s ability to sense intrinsic rate (the lower the sensitivity, the more the pacer will detect intrinsic rate; for example, at 3 mV, the pacer will only detect impulses generated from the heart that are greater than 3 mV)
  • Oversensing- Sensitivity is set too LOW so electrical signals are inappropriately recognized as cardiac activity and pacing is inhibited
  • Undersensing- Sensitivity is set too HIGH so pacemaker ignores native cardiac activity

Location

• Right internal jugular—preferred
• Left subclavian—use as second option, preferred to leave site available for possible permanent pacer

Steps to placing transvenous pacemaker

• Place cordis
• Set up nonsterile connecting cable (helpful to have assistant connect cable to pacer generator as these are not sterile)
• Ensure proper balloon inflation on Swan Ganz
• Position sterile sleeve over pacer wire and ensure correct orientation
• Insert pacer wire into cords and advance to 20cm (indicated by first two black lines)
• Insert Swan-Ganz + and – pins into nonsterile connecting cable (proximal to positive, distal to negative)
• Have assistant turn on pacer generator with the above settings (remember it is non sterile)
• Inflate balloon and lock purple stopcock (stopcock is on Swan, catheter see below image)
• Advance pacer wire to ~30-35cm (three black lines on pacer wire) while watching monitor for capture (STEMI pattern)
• Troubleshooting: 
  • if wire coils in RA, pull wire back, twist 180˚ towards patient’s right and re-advance
  • if wire fails to capture, can adjust pacer generator settings, consider increasing output and decreasing sensitivity
• Verify capture by either palpating pulse or by pulse ox waveform
• Decrease output until there is no longer capture, then titrate up to the lowest effective output
• Deflate balloon and turn stopcock off
• Expand sterile sleeve
• Suture cordis and place sterile dressing
• Secure pacer wire to patient with tape (can dislodge easily)

Complications

• Misplacement—can verify with ultrasound or chest x-ray
• Ventricular perforation
• Dysrhythmias
• Pneumothorax