S1W6 Cardiac Physiologist Role Cath Lab AM

Cardiac Catheterisation Overview

  • Role of Cardiac Physiologist: Annabelle Malone, Clinical Cardiac Scientist.

Content Breakdown

  • Patient and equipment setup

  • ECG positions

  • Oxygen Saturations (Sats)

  • Haemodynamic monitoring and pressure bag

  • Continuous Monitoring: ECG, Pressure waveforms

  • Proper Documentation

  • Troubleshooting tips

Set Up Steps

Initial Communication

  • Introduce yourself to the patient

  • Explain the procedure to alleviate patient anxiety.

ECG Set Up

  • Attach limb leads and one chest lead.

  • Do not place chest lead on the chest to prevent obstruction of x-ray images.

  • Keep electrodes clear of the access site area.

  • Ensure proper skin preparation prior to electrode application.

Oxygen Saturations

  • Use pulse oximeter on the digit opposite to the access side; toe digit may be used if necessary.

  • Blood saturations needed for calculations of shunts, cardiac output, and resistance.

  • Calibration of oximeter generally required using QC standards.

Oximeter Setup Tips

  • Require calibration with QC1, QC2, and QC3.

  • Prepare curvettes and ensure Hb levels are known.

  • Have essential materials ready (e.g., inko pads, syringes).

  • For MacLab setups, configure for continuous recordings for retrospective data acquisition.

Transducer Setup

Video Guidance

  • Refer to specified video (2:33-6:28) for proper transducer setup.

Key Setup Guidelines

  • New transducer and saline bag are mandatory for each procedure.

  • Always verify saline bag's contents and expiration with a colleague.

  • Saline solution (Sodium chloride 0.9%) is typically used for flushing; sometimes heparinised saline is required.

  • Important to flush before use to eliminate air bubbles.

  • Set the pressure of the saline bag higher than the patient's systolic (300-400 mmHg).

  • Align the manifold mid-chest level for accurate pressure measurement.

  • Zero the pressure with the transducer open to air.

  • Confirm transducer connection to output for pressure trace visibility.

Monitoring Parameters

ECG Monitoring

  • Display screen should typically show 4-5 ECG leads.

  • Capture a snapshot of the ECG rhythm and rate prior to the procedure, noting any abnormalities - BASELINE ECG

  • Continuous monitoring required throughout the procedure with active communication regarding significant changes.

Significant ECG Changes to Monitor

  • Ischemic changes: ST depression, T wave inversion, ST elevation.

  • Rhythm variations: Atrial fibrillation, Atrial flutter, Ventricular tachycardia, Ventricular fibrillation.

  • Notable conduction abnormalities and ectopic beats frequency.

  • Consider bradycardia/tachycardia changes.

Responses to ECG Abnormalities

  • Recognize potential transient ST changes caused by factors like catheter occlusion or coronary artery spasm.

  • Be aware that catheter introduction can induce ventricular ectopics and other arrhythmias.

  • Sudden bradycardia and vasovagal episodes may occur; monitor and manage appropriately.

Haemodynamic Monitoring

Monitoring Techniques

  • Real-time graph displaying intracardiac and arterial pressures.

  • Adjust scale according to the procedure and remember to record each chamber accessed during diagnostic angiography.

Key Pressures to Record

  • Normal ranges for various pressures are as follows:

    • PA: 15-25/8-12 mmHg

    • Ao: 120/80 mmHg

    • LA/PCWP: 6-12 mmHg

    • RA: 0-8 mmHg

    • RV: 15-25/0-8 mmHg

    • LV: 120/5-10 mmHg

Documentation Importance

  • Maintain accurate records of the procedure including times, team members present, fluoroscopy time/dose, ECG, and pressure data.

Troubleshooting Common Issues

ECG Potential Errors

  • Check electrodes, lead connections, and lead integrity if baseline artifacts arise.

  • Address any connectivity or positioning issues immediately.

Oximeter Errors

  • Assess probe positioning and potential falsifying factors like cold digits or mechanical errors.

  • If dropping Sats, assure probe integrity before escalating to oxygen therapy considerations.

Haemodynamic Monitoring Issues

  • Investigate abnormal pressures by confirming zero reference and level of the transducer.

  • Be vigilant for air bubbles, leaks, or loose connections affecting data integrity.

References

  • Klein, L., Korpu, D. (2017). Damped and Ventricularized Coronary Pressure Waveforms. J INVASIVE CARDIOL, 29(11):387-389.

  • Callan P, Clark AL. (2016). Right heart catheterisation: indications and interpretation. Heart, 102:147–157.