Mechanical Ventilation Management

Introduction to Mechanical Ventilation

• The European Society of Cardiology recommends cautious use of opioids due to their association with higher rates of mechanical ventilation, ICU admission, and death in patients with cardiac conditions 1
• The European Society of Cardiology suggests reserving sympathomimetics/vasopressors for patients with persistent hypoperfusion despite adequate filling status, as per their guidelines 1

Monitoring and Assessment

• The European Heart Association recommends regular monitoring of arterial blood gases to assess oxygenation, ventilation, and acid-base status, as well as assessment of respiratory mechanics, work of breathing, and patient-ventilator synchrony in mechanically ventilated patients 2
• Echocardiography should be used to assess cardiac function and evaluate left and right ventricular function and exclude mechanical complications, as recommended by the American College of Cardiology 3
• Tissue perfusion should be assessed using ultrasound evaluation of inferior vena cava, pulse pressure variation observations, central venous pressure monitoring, and urine output and metabolic acidosis as clinical indices of perfusion, according to the Intensive Care Medicine guidelines 4

Oxygenation Management

• The European Heart Association notes that hyperoxia can reduce coronary blood flow and cardiac output, and therefore should be avoided in patients receiving oxygen therapy 2
• Oxygen supplementation should be provided to maintain arterial saturation above 90% for patients with pulmonary congestion, as recommended by the American College of Cardiology 3
• The European Heart Journal recommends avoiding hyperoxia in patients receiving oxygen therapy 5

Ventilation Settings

• Initial ventilation settings for intubation and mechanical ventilation are recommended as follows:

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Weaning from Mechanical Ventilation

• The European Heart Association recommends conducting a spontaneous breathing trial (SBT) when the patient is ready, and if successful, proceeding with extubation, considering post-extubation NIV (CPAP or BiPAP) to prevent reintubation in high-risk patients 2
• Delayed weaning from mechanical ventilation can increase the risk of ventilator-associated pneumonia and other complications, as warned by the European Heart Association 2

Non-Invasive Ventilation

• Non-invasive positive pressure ventilation (CPAP, BiPAP) should be considered for patients with respiratory distress (respiratory rate >25 breaths/min, SpO2 <90%) 5, 7
• The American Thoracic Society recommends CPAP with entrained oxygen as adjunctive treatment to improve gas exchange in patients not responding to standard treatment, with a starting PEEP of 5-7.5 cmH₂O and titrating up to 10 cmH₂O as needed 8
• Non-invasive positive pressure ventilation (CPAP, BiPAP) should be implemented for respiratory distress (respiratory rate >25 breaths/min, SaO2 <90%) in patients with pulmonary edema, as recommended by the European Heart Journal guidelines 7

Management of Pulmonary Congestion

• IV furosemide is first-line therapy for pulmonary congestion with volume overload, with an initial dose of 40 mg IV given slowly (1-2 minutes), and considering at least equivalent to oral dose for patients already on chronic diuretic therapy 3, 9, 1, 10
• Nitrates (IV nitroglycerin) should be used for patients with systolic blood pressure >110 mmHg, starting with a dose of 10-20 μg/min and increasing in increments of 5-10 μg/min every 3-5 minutes, while avoiding its use in patients with SBP <110 mmHg 11, 9, 1, 8, 2, 12
• The American College of Cardiology recommends avoiding vasodilators in patients with systolic blood pressure <90 mmHg or >30 mmHg below baseline 3
• IV morphine 2.5-5 mg can be used to relieve dyspnea, anxiety, and improve cooperation with NIV, with caution in patients with hypotension, bradycardia, advanced AV block, or CO2 retention, although routine use of opioids is not recommended due to association with higher rates of mechanical ventilation, ICU admission, and death 13, 1, 8, 3, 10, 2, 14, 11

Fluid Management

• Monitor fluid balance, urine output, renal function, and electrolytes in patients with pulmonary congestion, and avoid excessive fluid administration which can decrease oxygenation, precipitate cor pulmonale, and worsen cardiac output, blood pressure, and RV function 3, 5, 4
• A fluid conservative strategy should be implemented in patients with pulmonary edema and atrial fibrillation with rapid ventricular response (AFIB RVR), focusing on diuresis with furosemide while maintaining rate control of the AFIB RVR, as recommended by the Intensive Care Medicine guidelines 4
• The FACTT-lite approach should be followed to guide fluid administration, with furosemide administered when central venous pressure is >8 mmHg with urine output <0.5 mL/kg/h, and fluid bolus given when central venous pressure is <4 mmHg with urine output <0.5 mL/kg/h, according to the Intensive Care Medicine guidelines 4

Management of Cardiogenic Shock

• Early revascularization (PCI or CABG) should be considered for patients with ischemic etiology and cardiogenic shock with pulmonary edema 3, 10, 13, 12
• Echocardiography should be considered to evaluate cardiac function and invasive hemodynamic monitoring in selected cases, and mechanical circulatory support for refractory cases of cardiogenic shock with pulmonary edema 3, 13, 14, 11, 12
• Continuous monitoring of heart rate, rhythm, blood pressure, and oxygen saturation is recommended for at least 24h, with consideration of intra-aortic balloon pump or other mechanical circulatory support in patients without contraindications 13, 3, 10

Complications of Mechanical Ventilation

• Patients with pulmonary edema should be assessed for acute cor pulmonale (ACP), which occurs in 20-25% of ARDS patients, as stated by the Intensive Care Medicine guidelines 4
• If RV failure is present, fluid overload should be avoided and norepinephrine should be considered to improve RV function by restoring mean arterial pressure and RV blood supply, as recommended by the Intensive Care Medicine guidelines 4
• Avoid aggressive simultaneous use of hypotension-inducing agents, which may precipitate cardiogenic shock 3
• Beta-blockers or calcium channel blockers should not be administered acutely to patients with pulmonary congestion 3
• For diuretic resistance, consider combination therapy with thiazides or aldosterone antagonists 11