What is the initial management of a patient presenting with chest pain (CP) suspected to be of cardiac origin using MONA (Morphine, Oxygen, Nitrates, Aspirin) therapy?

From the Guidelines

The initial management of a patient presenting with chest pain suspected to be of cardiac origin should prioritize activating EMS and administering aspirin 162-324mg, as it improves survival in patients with myocardial infarction 1. When considering the MONA therapy for cardiac chest pain, it's essential to weigh the benefits and risks of each component.

• Aspirin administration is supported by a 2020 systematic review that found early or first aid administration of aspirin to adults with nontraumatic chest pain was associated with reduced mortality 1.
• The use of oxygen is not recommended by the American Heart Association for people with acute coronary syndromes who are not hypoxic 1.
• Morphine and nitrates may be considered for pain management and to reduce cardiac preload, but their administration should be guided by clinical judgment and patient-specific factors.
• The most critical step is to activate EMS and provide aspirin, as delayed treatment can lead to poor outcomes. Key considerations in the initial management of cardiac chest pain include:
• Activating EMS promptly
• Administering aspirin 162-324mg to improve survival
• Avoiding unnecessary oxygen administration
• Continuously monitoring vital signs and obtaining a 12-lead ECG within 10 minutes of arrival
• Establishing IV access and drawing cardiac biomarkers to guide further diagnostic evaluation and treatment.

From the FDA Drug Label

The initial dose of morphine sulfate injection, give attention to the following: the total daily dose, potency and specific characteristics of the opioid the patient has been taking previously; the reliability of the relative potency estimate used to calculate the equivalent morphine sulfate injection dose needed; the patient’s degree of opioid tolerance; the general condition and medical status of the patient; concurrent medications; the type and severity of the patient’s pain; risk factors for abuse, addiction or diversion, including prior history of abuse, addiction or diversion One tablet should be dissolved under the tongue or in the buccal pouch at the first sign of an acute anginal attack. The dose may be repeated approximately every 5 minutes until relief is obtained.

The initial management of a patient presenting with chest pain (CP) suspected to be of cardiac origin using MONA (Morphine, Oxygen, Nitrates, Aspirin) therapy involves:

• Administering Morphine cautiously, considering the patient's medical status, opioid tolerance, and pain severity, with a usual starting dose of 0.1 mg to 0.2 mg per kg every 4 hours as needed 2
• Providing Oxygen as needed
• Giving Nitrates, such as nitroglycerin, sublingually, with one tablet dissolved under the tongue or in the buccal pouch at the first sign of an acute anginal attack, and repeating the dose approximately every 5 minutes until relief is obtained 3
• Administering Aspirin as soon as possible Note: These medications should be used under careful medical supervision, with attention to potential side effects and interactions. 2 3

From the Research

Initial Management of Chest Pain (CP) Suspected to be of Cardiac Origin

The initial management of a patient presenting with chest pain (CP) suspected to be of cardiac origin involves the use of MONA therapy, which includes:

• Morphine: to relieve chest pain 4
• Oxygen: to increase oxygen supply to the heart 4, 5
• Nitrates: such as nitroglycerin, to reduce cardiac workload and improve blood flow to the heart 4, 5
• Aspirin: to prevent blood clots from forming and reduce the risk of myocardial infarction 4, 5

Rationale for MONA Therapy

The use of MONA therapy is based on the principle of reducing cardiac workload, improving blood flow to the heart, and preventing blood clots from forming. This approach has been shown to be effective in reducing mortality and morbidity in patients with acute coronary syndrome (ACS) 5.

Contemporary Management of Acute Coronary Syndromes

While MONA therapy is still widely used, contemporary management of ACS has evolved to include additional therapies, such as:

• Thienopyridines: to prevent blood clots from forming 5
• Heparin/enoxaparin: to prevent blood clots from forming 4, 5
• Renin-angiotensin system blockers: to reduce blood pressure and reduce cardiac workload 5
• Beta blockers: to reduce cardiac workload and improve blood flow to the heart 4, 5
• Statins: to reduce cholesterol levels and prevent blood clots from forming 5

Limitations of MONA Therapy

While MONA therapy is effective in reducing mortality and morbidity in patients with ACS, it has limitations. For example, the use of morphine and nitrates may not be suitable for all patients, and aspirin may not be effective in preventing blood clots in all patients 5. Additionally, MONA therapy does not address the underlying cause of the chest pain, and further testing and evaluation may be necessary to determine the cause of the chest pain 6, 7, 8.