What is the protocol for managing cardiogenic shock?

From the Guidelines

The management of cardiogenic shock should prioritize a team-based approach, incorporating both pharmacological and mechanical therapies, with the goal of restoring cardiac output and tissue perfusion, as recommended by the 2022 AHA/ACC/HFSA guideline 1. The protocol for managing cardiogenic shock involves immediate identification and treatment to restore cardiac output and tissue perfusion.

Key Components of Management

• Begin with rapid assessment and stabilization, including continuous cardiac monitoring, arterial line placement, and central venous access.
• Initial management includes oxygen supplementation to maintain saturation above 94% and mechanical ventilation if respiratory failure occurs.
• Fluid resuscitation should be cautious with small boluses (250-500 mL) while monitoring for pulmonary edema.
• Pharmacological support typically starts with norepinephrine (0.01-3 mcg/kg/min) as the first-line vasopressor to maintain mean arterial pressure above 65 mmHg, as suggested by the European Heart Journal 1.
• Add dobutamine (2-20 mcg/kg/min) for inotropic support if blood pressure allows.
• For refractory cases, consider epinephrine (0.01-0.5 mcg/kg/min), vasopressin (0.01-0.04 units/min), or milrinone (0.375-0.75 mcg/kg/min).

Mechanical Circulatory Support

• Early mechanical circulatory support with intra-aortic balloon pump or Impella should be considered, especially in patients not responding to initial therapy.
• The use of short-term mechanical circulatory support (MCS) has dramatically increased, despite the lack of direct comparative data, as noted in the 2022 AHA/ACC/HFSA guideline 1.
• The choice of MCS device should be guided by the patient's specific needs and the availability of devices.

Monitoring and Adjustment

• Continuous hemodynamic monitoring is essential to guide therapy, with goals including cardiac index >2.2 L/min/m², mixed venous oxygen saturation >65%, and lactate clearance.
• The management of cardiogenic shock should be tailored to the individual patient's needs, with consideration of their underlying cause of cardiac failure, comorbidities, and overall prognosis.
• A team-based approach, incorporating both pharmacological and mechanical therapies, is essential for the effective management of cardiogenic shock, as it allows for the escalation of therapy and the provision of palliative care, as recommended by the 2022 AHA/ACC/HFSA guideline 1.

From the FDA Drug Label

Dopamine Hydrochloride in 5% Dextrose Injection, USP is indicated for the correction of hemodynamic imbalances present in shock due to myocardial infarction, trauma, endotoxic septicemia, open heart surgery, renal failure and chronic cardiac decompensation as in refractory congestive failure When indicated, restoration of circulatory volume should be instituted or completed with a suitable plasma expander or whole blood, prior to administration of dopamine hydrochloride. Suggested Regimen:

1. When appropriate, increase blood volume with whole blood or plasma until central venous pressure is 10 to 15 cm H2O or pulmonary wedge pressure is 14 to 18 mm Hg.
2. Begin infusion of dopamine hydrochloride solution at doses of 2 to 5 mcg/kg/min in adult or pediatric patients who are likely to respond to modest increments of heart force and renal perfusion In more seriously ill patients, begin infusion of dopamine hydrochloride at doses of 5 mcg/kg/min and increase gradually, using 5 to 10 mcg/kg/min increments, up to a rate of 20 to 50 mcg/kg/min as needed.

The protocol for cardiogenic shock involves:

• Restoration of circulatory volume with a suitable plasma expander or whole blood prior to administration of dopamine hydrochloride
• Initial infusion rate of dopamine hydrochloride at 2 to 5 mcg/kg/min, which may be increased gradually as needed up to 20 to 50 mcg/kg/min
• Monitoring and adjustment of dosage according to the patient's response, including urine flow, cardiac output, blood pressure, and distribution of peripheral perfusion 2 2
• Key considerations:
  • Increase blood volume until central venous pressure is 10 to 15 cm H2O or pulmonary wedge pressure is 14 to 18 mm Hg
  • Begin infusion at doses of 2 to 5 mcg/kg/min and increase gradually as needed
  • Monitor urine output frequently, especially if doses exceed 50 mcg/kg/min
  • Decrease dopamine dosage if urinary flow begins to decrease in the absence of hypotension

From the Research

Protocol for Cardiogenic Shock

The management of cardiogenic shock is based on immediate stabilization of haemodynamic parameters, and medical therapy, consisting mainly of inotropic drugs and vasopressors, still has a major role 3.

Medical Therapy

• Inotropic agents, such as dobutamine, are used to improve cardiac contractility, while vasopressors, such as norepinephrine, are used to increase blood pressure 4, 5.
• Norepinephrine is recommended as the first-line vasopressor agent, due to its minimal adverse effects and association with the best outcome in network meta-analyses 4, 5.
• Dobutamine is the first-line inotrope agent, while levosimendan can be used as a second-line agent or preferentially in patients previously treated with beta-blockers 4, 5.

Hemodynamic Profile

• The choice of inotropic and vasopressor agents should be individualized and based on the patient's hemodynamic profile 6, 4.
• Vasopressin may be an excellent alternative in tachycardiac patients or in the presence of pulmonary hypertension 4.

Limitations of Current Evidence

• There is limited evidence regarding the effectiveness of vasopressors and inotropes in improving outcomes in cardiogenic shock 5.
• Two recent Cochrane analyses concluded that there was not sufficient evidence to prove that any one vasopressor or inotrope was superior to another in terms of mortality 5.

Multidisciplinary Approach

• The management of cardiogenic shock requires a multidisciplinary approach in a critical care setting, incorporating both pharmacologic and nonpharmacologic therapies to minimize morbidity and mortality 7.