Cardiology ICU Protocol and Management
Admission Criteria and Triage
Patients with acute coronary syndromes (ACS) presenting with ongoing angina, hemodynamic instability, uncontrolled arrhythmias, large MI with heart failure, or cardiogenic shock must be admitted to a cardiac intensive care unit (CICU). 1
Severity-Based Triage Criteria
Immediate CICU/Resuscitation Area admission is required for:
- Respiratory distress: RR >25/min, SpO₂ <90% on oxygen, or increased work of breathing 1
- Hemodynamic instability: SBP <90 mmHg or >140 mmHg with severe symptoms, severe arrhythmia, HR <40 or >130 bpm 1
- Signs of hypoperfusion: oliguria, cold peripheries, altered mental status, lactate >2 mmol/L, metabolic acidosis, SvO₂ <65% 1
- Need for intubation or already intubated 1
Stable patients without recurrent ischemia, significant arrhythmias, pulmonary edema, or hemodynamic instability can be admitted to intermediate care or telemetry units rather than CICU. 1
Risk Stratification Tools
The ACTION ICU risk score integrates 9 variables to identify patients requiring CICU care: signs/symptoms of HF, initial heart rate, initial SBP, initial troponin, initial serum creatinine, prior revascularization, chronic lung disease, ST-segment depression, and age >70 years 1
CICU Monitoring Requirements
The nurse-to-patient ratio must be sufficient to provide:
- Continuous electrocardiographic rhythm monitoring 1
- Frequent assessment of vital signs and mental status 1
- Ability to perform rapid cardioversion and defibrillation for arrhythmias 1
Electrocardiographic monitoring leads should be based on infarct location and rhythm to optimize detection of ST deviation, axis shift, conduction defects, and dysrhythmias. 1
Essential monitoring parameters include:
- Dyspnea assessment (Visual Analogue Scale, respiratory rate) 1
- Blood pressure and SpO₂ 1
- Heart rate and rhythm 1
- Urine output 1
- Peripheral perfusion 1
Management of Acute Coronary Syndromes
STEMI Management
Time-to-treatment is critical—all ACS patients should receive appropriate therapy as early as possible. 1
Pre-hospital and Initial Therapy
Aspirin administration is mandatory prior to primary PCI (PPCI). 1
Pre-hospital loading doses of P2Y12 inhibitors are recommended prior to PPCI:
- Ticagrelor and prasugrel are first-line P2Y12 inhibitors (considering contraindications) 1
- Clopidogrel is recommended when ticagrelor or prasugrel are unavailable or contraindicated 1
- Withhold pre-hospital antithrombotic therapy in the presence of high bleeding risk or uncertain STEMI diagnosis 1
Anticoagulation regimens:
- Enoxaparin is first-line therapy, or UFH if enoxaparin is not available, during transfer for PPCI 1
- Bivalirudin is first-line anticoagulation in STEMI patients at high bleeding risk and/or elderly, with >4h infusion recommended after PPCI 1
- Fondaparinux is not recommended for use in PPCI 1
Upstream GP2b3a inhibition may be considered prior to PPCI in high-risk patients (extensive infarct) presenting early (<2h) after symptom onset, only in patients at low bleeding risk. 1
CICU Management
Medication regimen review should confirm:
- Administration of aspirin and beta-blockers in adequate dose to control heart rate 1
- Assessment of need for intravenous nitroglycerin for control of angina, hypertension, or heart failure 1
Supplemental oxygen:
- Ongoing need should be assessed by monitoring arterial oxygen saturation 1
- When stable for 6 hours, reassess for oxygen need (O₂ saturation <90%) and consider discontinuation 1
Bed rest should not exceed 12-24 hours for patients free of recurrent ischemic discomfort, symptoms of heart failure, or serious disturbances of heart rhythm. 1
After 12-24 hours, allow patients with hemodynamic instability or continued ischemia to have bedside commode privileges. 1
NSTE-ACS Management
For NSTE-ACS, clopidogrel (300 mg loading dose followed by 75 mg once daily) plus aspirin reduces the rate of cardiovascular death, MI, and stroke by 20% compared to aspirin alone. 2
High-risk patients with hemodynamic instability or signs of heart failure require transfer to emergency departments with critical care or intensive cardiac care units and 24/7 interventional cardiology capability. 1
In patients with persistent symptoms despite initial therapy, direct transfer to a catheterization laboratory is recommended. 1
Thrombotic and bleeding risk assessment is highly recommended in NSTE-ACS. 1
Target heart rate <60 beats/min and systolic blood pressure between 100-120 mmHg in the absence of neurological complications. 1, 3
Management of Acute Heart Failure
Immediate Interventions
Acute heart failure is a life-threatening condition requiring immediate medical attention, defined by rapid onset or acute worsening of symptoms/signs of HF with elevated natriuretic peptides. 1
Most AHF patients present with normal or high blood pressure and symptoms/signs of congestion rather than low cardiac output. 1
Respiratory Support
Oxygen therapy should be initiated immediately with target saturation >94% to address hypoxemia from pulmonary edema. 3
Non-invasive ventilation (CPAP or NIPPV) should be considered promptly if respiratory distress is present. 1, 3
Prepare for endotracheal intubation and invasive ventilation if respiratory failure develops with hypoxemia, hypercapnia, acidosis, physical exhaustion, or diminished consciousness. 3
Pharmacologic Therapy
Intravenous furosemide should be administered immediately as first-line diuretic for volume overload. 3
Sublingual or intravenous nitrates titrated to blood pressure reduce preload and afterload. 3
Morphine may be considered for dyspnea relief, but use caution as opiates can depress respiration and require frequent monitoring. 3
Opioid use should be titrated according to pain evaluation, with caution to limit doses as much as possible due to potential interaction with oral antiplatelet therapy. 1
Treatment Objectives
Primary goals are to:
Diagnostic Evaluation
Point-of-care troponin testing should be performed urgently to assess for concurrent myocardial infarction. 3
Echocardiography is mandatory to assess valve function, ventricular function, and exclude mechanical complications. 3
Bedside thoracic ultrasound for signs of interstitial edema and abdominal ultrasound for inferior vena cava diameter (and ascites) if expertise is available. 1
AHF with Acute Coronary Syndrome
Patients with AHF and associated acute coronary syndrome should be referred to CCU. 1
Guidelines recommend an immediate invasive strategy for patients with acute heart failure and acute coronary syndrome, regardless of electrocardiographic or biomarker findings. 4
The combination of ACS and AHF is associated with higher short-term mortality compared to ACS alone, with in-hospital case-fatality rates of 29.7% for de novo acute HF and 32.6% for acute decompensated chronic HF. 5
Management of Arrhythmias
Atrial Arrhythmias
Atrial fibrillation is the main atrial arrhythmia in ACS; other forms are rare and usually self-limited. 6
Therapeutic options include:
Patients with arrhythmias that are hemodynamically well-tolerated (e.g., atrial fibrillation with controlled ventricular response, paroxysms of nonsustained VT lasting <30 seconds) can be managed on stepdown unit, provided facilities for continuous ECG monitoring, defibrillators, and appropriately skilled nurses are available. 1
Ventricular Arrhythmias
Ventricular arrhythmias include premature ventricular complexes, accelerated idioventricular rhythm, non-sustained VT, sustained VT, VF, and electrical storm. 6
Therapeutic options include:
- Antiarrhythmic drug therapy (cautiously recommended, except beta-blockers) 6
- Additional drug therapy with ranolazine may be considered 6
- Implantable cardioverter defibrillator (ICD) therapy for long-term primary or secondary prophylaxis is associated with significant mortality reduction compared to antiarrhythmic drugs (mainly amiodarone), except beta-blockers 6
- Radiofrequency catheter ablation (RFA) and stellate ganglion blockade for incessant VT/VF or electrical storm 6
The main common dominant mechanisms are intramural re-entry in ischemia and triggered activity in reperfusion. 6
Transfer and Stepdown Criteria
Transfer from CICU to Stepdown Unit
STEMI patients originally admitted to CICU who demonstrate 12-24 hours of clinical stability (absence of recurrent ischemia, heart failure, or hemodynamically compromising dysrhythmias) should be transferred to stepdown unit. 1
Low-risk STEMI patients who have undergone successful PCI can be admitted directly to stepdown unit for post-PCI care rather than CICU. 1
Patients recovering from STEMI with clinically symptomatic heart failure can be managed on stepdown unit, provided facilities for continuous pulse oximetry monitoring and appropriately skilled nurses are available. 1
Length of Stay
Early discharge strategy of <3 days from admission is not associated with increased mortality for low-risk patients after STEMI who have undergone PCI. 1
The Zwolle score has been recommended for risk stratification to guide discharge timing. 1
Anemia Management
In patients with ACS and acute or chronic anemia, blood transfusion to achieve hemoglobin ≥10 g/dL may be reasonable to reduce cardiovascular events. 1
This represents a more liberal transfusion strategy than the restrictive approach (targeting hemoglobin ~8 g/dL) used in other populations, based on randomized trial evidence suggesting possible clinical benefit in ACS. 1
Common Pitfalls to Avoid
Do not admit terminally ill "do not resuscitate" patients with STEMI to CCU, as clinical and comfort needs can be provided outside critical care environment. 1
Do not delay diuretics and vasodilators while awaiting diagnostic confirmation in AHF—clinical presentation warrants immediate treatment. 3
Do not assume left bundle branch block is chronic without comparison to prior ECGs—new LBBB with chest pain is a STEMI equivalent requiring urgent catheterization. 3
Do not administer antithrombotic therapy until aortic dissection is excluded. 3
Care of STEMI patients in CCU should be structured around protocols derived from practice guidelines. 1
Nursing care should be provided by individuals certified in critical care, with staffing based on specific needs of patients and provider competencies. 1