#13. How to prioritize which patients should be monitored with ECG?

Hello, I am Dr. Nicola Cosentino. Welcome to this podcast series on ECG monitoring, sponsored by GE Healthcare. Today´s topic will be on how to prioritize which patients should be monitored with ECG.

Continuous ECG monitoring was first introduced nearly 60 years ago for critically ill patients, but today is used increasingly to monitor patients with a variety of conditions. Early monitoring focused on heart rate measurement and fatal arrhythmia detection. Today, monitoring has expanded to include diagnoses of complex arrhythmias, acute myocardial ischemia, and prolonged QT intervals and, hence, it is currently applied in a variety of critical and non-critical care hospital settings.

When a patient is hospitalized, the first rule is to perform a 12-lead ECG; this will allow to have a baseline ECG for any comparison during hospitalization. Then, we should decide who deserves to be monitored? A basic rule is that, regardless of the underlying acute condition leading to hospitalization, if the patient is in hemodynamic, respiratory, or neurologic distress then of course you need to continuously monitor them. It must be included for every one of these patients in order to promptly evaluate rapid deterioration or to immediately detect life-threatening arrhythmias. So, as a general rule, all patients admitted to intensive care unit need to be continuously monitored.

Among “acute cardiac” patients, those during their early-phase acute coronary syndrome should be immediately monitored (STEMI patients for at least 48hrs and intermediate-high risk NSTEMI patients for at least 24hrs). It is also reasonable to perform continuous ST-segment monitoring in patients in whom there is the suspicion of ongoing myocardial ischemia. All patients with ventricular tachycardia (VT, ventricular fibrillation, or hemodynamically unstable VT should be monitored until a ICD is implanted or underlying problem resolved. For all arrhythmias, add ST-segment monitoring if ischemic origin is suspected. Moreover, patients with non-sustained VT, new or recurrent atrial fibrillation (AF), or hemodynamically unstable or symptomatic AF should be monitored until treatment strategy is determined or during ongoing rate control management and during initiation of a new antiarrhythmic agent. For sinus bradycardias, an indication for continuous ECG monitoring are symptomatic sinus bradycardia (<50 bpm), significant bradycardia (<40 bpm) regardless of symptoms, symptomatic atrio-ventricular (AV) block or asymptomatic second- or third degree AV block caused by distal conduction system disease (as suggested by a wide QRS complex). For WPW, Brugada, or LQTS, continuous ECG monitoring is recommended in the case of hemodynamic instability, or if recurrent syncope or recurrent VT until appropriate therapy is delivered or until QTc returns to baseline. In particular, patients with a baseline QTc >500 msec (>550 msec if bundle branch block or ventricular pacing) or those showing an increase in QTc >60 ms (or >25%) from baseline, are at risk of developing torsade de pointes or sudden death and need to be continuously monitored.

Continuous ECG monitoring is also recommended for non-cardiac patients with major trauma, acute respiratory failure, sepsis, shock, acute pulmonary embolus, renal failure with electrolyte abnormalities (e.g. until normalization of electrolytes of hyperkalaemia), and drug overdose (especially from tricyclic antidepressants and/or antiarrhythmic, until patients are free of the influence of the drug(s) and clinically stable). In addition, in patients with acute stroke, continuous ECG monitoring for 24-48hrs is recommended or for longer time periods if cryptogenic stroke and occult atrial fibrillation is suspected.

Patients undergoing major cardiac interventions should be monitored 48–72 hrs, if uncomplicated. After non-cardiac major thoracic surgery (such as pulmonary resection) ECG monitoring should be performed for 48/72 hrs to identify AF. In any case, for all major non-cardiac surgeries (especially in older patients with a history of coronary artery disease or coronary risk factors), continuous ECG monitoring may be beneficial during the first post-operative 48/72 hrs.

If a patient is required to leave the monitored unit for diagnostic or therapeutic procedures, then cardiac monitoring should be continued with a portable, battery-operated monitor-defibrillator. Continuous ECG monitoring is also indicated in patients undergoing diagnostic/therapeutic procedures requiring conscious sedation or anesthesia and should be continued until patients are awake, alert, and hemodynamically stable.

In summary, the first rule is to perform a 12 lead ECG at admission in all hospitalized patients; secondly, if you have a clinical doubt, monitor the patient as this may help you save time and lives. Thirdly, documentation with a “stat” standard 12-lead ECG if the monitored rhythm modifies. Any patient acutely unwell is at risk of life-threating arrythmias and/or may quickly deteriorate and evolve towards overt shock so she/he should be continuously ECG monitored. Last, but not least, hospitalized patients should be assessed daily for the appropriateness of cardiac monitoring.

Thanks for listening to this podcast on how to prioritize which patients should be monitored with ECG. The next podcast of this series will be on admission pathways of ACS