Dysrhythmias and Conduction Disturbances: Recognition, Monitoring and Nursing Management
Recognition
Use a systematic ECG approach: rate, rhythm, P waves, PR interval, QRS width, and P-to-QRS relationship. Regular narrow-complex tachycardias include sinus tachycardia, SVT, and atrial flutter with fixed block; irregular narrow-complex rhythms suggest atrial fibrillation, multifocal atrial tachycardia, or variable block. Wide-complex tachycardia is VT until proven otherwise, especially with structural heart disease. Heart blocks range from benign first-degree to symptomatic second-degree and complete AV block.
Monitoring and management
Assess the patient first: pulse, blood pressure, consciousness, chest pain, and perfusion. Stable patients may need monitoring, electrolytes, oxygen if hypoxemic, and drug therapy. Unstable patients with a pulse need synchronized cardioversion; pulseless VT/VF needs defibrillation and CPR. Adenosine is diagnostic/therapeutic for stable regular SVT but not for irregular or wide rhythms. Anticoagulation matters in AF for stroke prevention.
Traps
Do not cardiovert a stable patient just because the monitor looks alarming. Do not give adenosine to a patient with severe asthma or wide-complex tachycardia of uncertain origin. Pacemaker spikes may be tiny; look for capture. Long QT and hypokalemia increase torsades risk.
Worked example
Regular narrow-complex tachycardia at 150 bpm: each R-R is two large boxes, so rate = 300/2 = 150. If the patient is hypotensive and confused, proceed to synchronized cardioversion rather than vagal maneuvers.