Acute myocardial infarction occurs when the oxygenated blood flow in the heart is stopped and interrupted for a long period of time. A suggested intervention is inhaled oxygen at a normal oxygen pressure to a patient in this condition, delivered by facemask or nasal cannula (Iscoe, Beasley & Fisher, 2011). The effectiveness of additional oxygen to a patient with acute myocardial infarction is that it might recover and improve the oxygenation of the ischaemic myocardial tissue and reduce ischaemic symptoms such as pain and size of the affected area, as well as reduce the mortality rate (Burgess, 2010). However, Burls, Bayliss, Emparanza and Quinn, (2011), found that the basis of existing administration of patients with acute myocardial infarction…show more content… According to Guthrie (2010) the risk of using oxygen in acute myocardial infarction are considered to be caused by the inconsistent result of oxygen depletion in coronary artery flow, and rising coronary vascular blocking, in addition to falling stroke level and cardiac productivity. Other unfavourable haemodynamically effects of oxygen therapy occur during improved vascular blocking from hyperoxia, and reperfusion injury from raised oxygen free radicals (Guthrie, 2010). Moradkhan and Sinoway, as cited in (Cabello, Burls, Emparanza, Bayliss, & Quinn, 2010) in their review, recommend extensive use of high levels of oxygen in acute myocardial infarction patients, to sustain oxygen saturations near to 100%. The result showed that numerous patients in the important stages of hyperoxia, resulting in decrease in the lumen of blood vessels as well as the production of active oxygen. There was also, decrease within cell ATP absorption intervening cavity of ATP-acute potassium channels, in order to increase polarization of vascular smooth muscle cells and an increase in the lumen of the blood vessels (cabello at al., 2010). Cabello et al. Conducted research on oxygen therapy in people who have had a heart attack. Their research use randomised controlled trials that compared the results for…show more content… In 1965, Thomas and colleagues (as cited in Beasley et al., 2007) believed that in the first days following myocardial infarction, an administration of 40% oxygen for 20 minutes affected an increase in the major blood pressure and a reduction in cardiac productivity (Guthrie, 2010). Also, high flow oxygen caused a decrease in cardiac productivity in patients with left ventricular failure and a baseline arterial oxygen saturation of ≥90% (Beasley et al., 2007). Russek and colleagues in their original study which published in 1950 observed that 100% oxygen through the face mask resulted in a clearer and longer period of the electrocardiograph (ECG) proof of myocardial ischemia and failed to anticipate the beginning or control the period of angina pain. The result of this study directed Beasley et al. (2007) to recommend that large amounts of oxygen in the blood may get in the way with immediate hyperaemia which is associated with an ischaemic myocardium. Nevertheless, they stressed that oxygen must be liberally ordered if indicated but may result in more harm than good in patients (Beasley et al., 2007). Caldeira, Vaz-Carneiro and Costa (2014) found that an additional disadvantage is associated with the way that acute coronary syndromes are treated. Today, patients routinely receive therapies that have a significant impact on prognosis, including dual anti-platelet