What is the best course of action for an elderly male patient with a permanent pacemaker (artificial cardiac pacemaker), presenting with body weakness, shortness of breath, mild tremors, seizures, and status epilepticus, with an unremarkable computed tomography (CT) scan?

Immediate Management of Status Epilepticus in a Pacemaker Patient

This patient requires immediate treatment of status epilepticus with IV lorazepam 4 mg given slowly (2 mg/min), followed by a second-line anticonvulsant, while simultaneously investigating for pacemaker malfunction and correctable metabolic causes. 1

Critical First Steps

Airway and Vital Support

• Establish airway patency immediately and have ventilatory support equipment at bedside before administering any anticonvulsant. 1
• Start IV access, monitor vital signs continuously, and prepare for potential respiratory depression from benzodiazepine administration. 1
• The combination of status epilepticus treatment and potential pacemaker-related hemodynamic compromise creates dual respiratory and cardiovascular risks. 2, 1

Immediate Seizure Control

• Administer lorazepam 4 mg IV slowly at 2 mg/min for patients ≥18 years. 1
• If seizures persist after 10-15 minutes, give an additional 4 mg IV dose slowly. 1
• Status epilepticus is life-threatening with high risk of permanent neurological impairment if inadequately treated. 1, 3

Simultaneous Diagnostic Evaluation

Rule Out Pacemaker Malfunction FIRST

In any pacemaker patient presenting with weakness, dyspnea, and altered mental status progressing to seizures, assume pacemaker malfunction until proven otherwise. 2

• Syncope or confusional states in pacemaker patients must be presumed pacemaker-related until proved otherwise. 2
• Document heart rate immediately—ventricular rate <40 bpm in symptomatic patients indicates complete pacemaker failure in underlying complete heart block. 2
• Check for documented asystole or pauses ≥3 seconds, which are life-threatening in pacemaker-dependent patients. 2
• Obtain 12-lead ECG looking for absence of pacing spikes, failure to capture, or inappropriate sensing. 4

Identify Correctable Metabolic Causes

Status epilepticus may result from correctable acute causes that must be immediately sought and corrected. 1

• Check fingerstick glucose immediately to rule out hypoglycemia. 1
• Obtain stat electrolytes focusing on sodium (hyponatremia) and calcium. 1, 5
• Assess for hypoxia with pulse oximetry and arterial blood gas if indicated. 1, 5
• Consider drug toxicity, particularly if patient is on medications that could interact with pacemaker function or lower seizure threshold. 1

Second-Line Anticonvulsant Selection

If seizures continue after benzodiazepines, immediately administer a second-line agent—valproate is preferred in this elderly patient with cardiac disease. 5

Valproate Administration

• Give valproate 20-30 mg/kg IV (typically 1500-2000 mg for average adult) infused at 6 mg/kg/hour. 5
• Valproate demonstrated 79% seizure control as second-line therapy versus 25% with phenytoin in refractory status epilepticus. 5
• Critically important: Valproate causes no hypotension, unlike phenytoin which causes hypotension in 12% of patients—a dangerous complication in someone with potential pacemaker malfunction. 5

Alternative: Levetiracetam

• Levetiracetam is another acceptable second-line option with favorable hemodynamic profile. 5
• The Neurocritical Care Society recommends valproate, levetiracetam, or phenobarbital in addition to phenytoin/fosphenytoin for urgent seizure control. 5

Pacemaker-Specific Considerations

High-Risk Features in This Patient

• Pacemaker-dependent patients (complete heart block, post-AV junction ablation, no escape rhythm) are at highest risk from device failure. 2
• Body weakness, shortness of breath, and confusional states progressing to seizures suggest both hemodynamic compromise and cerebral hypoperfusion. 5, 2
• The unremarkable CT scan does not rule out pacemaker malfunction as the primary cause. 2

Immediate Pacemaker Assessment

• Apply magnet to pacemaker to assess battery function—if pacemaker responds with normal pacing, battery is adequate. 2
• A depleted battery would not respond to magnet application with normal pacing function. 2
• Check for cannon A waves (visible neck pulsations) suggesting loss of AV synchrony or pacemaker syndrome. 2, 6
• Assess for systolic blood pressure drops ≥20 mmHg during ventricular pacing, indicating pacemaker syndrome. 6

Common Pitfalls to Avoid

Do NOT Attribute Symptoms to Other Causes Prematurely

• Assuming symptoms are non-cardiac in pacemaker patients with confusional states, bradycardia, or syncope is a critical error—always suspect device malfunction first. 2
• The progression from weakness and dyspnea to seizures suggests worsening cerebral hypoperfusion from inadequate cardiac output. 5, 2

Do NOT Use Phenytoin as First Choice

• Phenytoin causes hypotension in 12% of patients and has only 56% success rate even when combined with diazepam. 5
• In a patient with potential pacemaker malfunction and hemodynamic instability, phenytoin's hypotensive effects could be catastrophic. 5

Do NOT Delay Cardiology Consultation

• If patient fails to respond to initial seizure management or has confirmed pacemaker malfunction, immediate cardiology consultation is mandatory. 2, 4
• Pacemaker interrogation and potential temporary pacing may be required. 4

Disposition and Ongoing Management

ICU Admission Required

• All patients with status epilepticus require ICU-level monitoring. 5, 3
• Pacemaker malfunction in elderly patients with seizures necessitates continuous cardiac monitoring and immediate access to temporary pacing capability. 2, 4

Maintenance Antiepileptic Therapy

• Patients susceptible to further seizure episodes must receive adequate maintenance antiepileptic therapy. 1
• Continue valproate infusion at 1-2 mg/kg/hour after loading dose. 5
• If underlying cause is pacemaker malfunction with cerebral hypoperfusion, seizures should resolve once adequate cardiac output is restored. 2

Neurologist Consultation

• Consult neurology if patient fails to regain consciousness after seizure cessation. 1
• Consider EEG monitoring to detect nonconvulsive status epilepticus, which may occur without motor activity. 3