Acute infarction, commonly known as a heart attack, is a life-threatening condition that requires immediate medical attention.

It occurs when the blood supply to a part of the heart is blocked, leading to tissue damage and potentially long-term complications. Oxygen therapy, the administration of supplemental oxygen, has been a standard treatment for patients with acute infarction for several decades.

However, recent studies have questioned its efficacy in improving patient outcomes and have raised concerns about potential harms associated with its use. This article aims to assess the efficacy of oxygen therapy in acute infarction based on the available evidence.

Background and Rationale

When a heart attack occurs, the blocked artery prevents oxygen-rich blood from reaching the heart muscle. As a result, the affected tissue may become starved of oxygen, leading to cell death and permanent damage.

The rationale behind oxygen therapy is to increase the oxygen supply to the heart, reduce the size of the infarction, and improve patient outcomes.

Evidence Supporting Oxygen Therapy

Several studies conducted in the past have suggested potential benefits of oxygen therapy in acute infarction.

These studies reported that supplemental oxygen might improve oxygen saturation levels, reduce chest pain, and limit the size of the infarction. Consequently, oxygen therapy became a routine intervention in the management of heart attacks.

Current Controversies and Contradictory Findings

However, recent randomized controlled trials have challenged the long-held belief in the efficacy of oxygen therapy for acute infarction.

The DETO2X-AMI trial, one of the largest studies conducted in this field, demonstrated that routine oxygen therapy did not reduce the rate of major cardiovascular events or mortality compared to ambient air. These findings contradict the previous studies that supported the use of oxygen therapy.

Moreover, some studies have even suggested potential harms associated with oxygen therapy. Excessive oxygenation may cause vasoconstriction, leading to reduced blood flow and exacerbation of ischemic injury.

There is also evidence that high oxygen levels can trigger oxidative stress and inflammation, which can further damage the heart tissue.

Clinical Guidelines and Recommendations

Given the contradictory findings and potential harms associated with oxygen therapy, clinical guidelines and recommendations have been revised.

The European Society of Cardiology (ESC) and the American Heart Association (AHA) no longer recommend routine oxygen administration for patients with uncomplicated acute infarction who have normal oxygen saturation levels. Instead, they emphasize the importance of maintaining oxygen saturation within the normal range without the routine use of supplemental oxygen.

Individualized Approach to Oxygen Therapy

While routine oxygen therapy may not provide significant benefits for all patients with acute infarction, there are still situations where it might be beneficial.

Patients with low oxygen saturation levels, signs of respiratory distress, or underlying lung disease may benefit from supplemental oxygen. Therefore, an individualized approach based on the patient’s clinical presentation and oxygen saturation levels is crucial in determining the appropriateness of oxygen therapy.

Conclusion

The efficacy of oxygen therapy in acute infarction has been debated in recent years. While past studies suggested benefits, recent evidence does not support routine oxygen therapy in uncomplicated cases.

Healthcare professionals should assess each patient individually, considering oxygen saturation levels and other clinical factors before making a decision regarding supplemental oxygen administration.