HIGH DEPENDENCY IN NURSING DURING MYOCARDIAL INFRACTION
High dependency in Nursing with a patient who has myocardial infraction leading to acute heart failure
High dependency in Nursing during Myocardial Infraction
In a patient with acute myocardial infarction (MI), the management of the MI itself may overshadow the management of heart failure or left ventricular systolic dysfunction (LVSD). There is a tendency for medical staff to concentrate on thrombolysis, rhythm disturbances, revascularisation, and resynchronisation therapy, with lower priority being given to pharmacological treatment of heart failure and LVSD. However, left ventricular function is one of the principal determinants of life expectancy after myocardial infarction and hospitals have an important role to play in establishing management objectives(Coffey, 1992). It is well recognised that patients are more likely to receive the correct treatments long term if they are started in hospital.1 The process of ventricular remodelling is thought to start immediately after the infarct and there is therefore good reason to start drugs for LVSD early. Of course, the early introduction of b blockers after infarction was recommended as long as 20 years ago by the early ISIS studies. There is also evidence that angiotensin converting enzyme (ACE) inhibitors should be introduced within the first 24 hours of MI if possible: the GISSI-3 trial2 showed that starting an ACE inhibitor (lisinopril) within 24 hours of symptom onset reduced mortality. Treatment for six weeks produced benefit at six months, with echocardiographic evidence of less remodelling. However, introduction of these drugs needs to be undertaken with some caution in view of the potential risks involved with treating previously hypertensive patients who have low blood pressure (, 120 mm Hg) on admission. Acute myocardial infarction (AMI) results from an imbalance between oxygen demand and oxygen supply to the myocardium. In 90 percent of the cases of AMI, this imbalance is preceded by atherosclerosis and decreased blood flow in the coronary arteries. The inadequate blood flow results in decreased oxygen delivery to the heart muscle, which causes ischemia, injury, and death of a portion of the myocardium (infarction).( Hofmann, 1993)
Logistics Of Management Of Heart Failure
In the post-MI situation, the management of heart failure and LVSD is only part of the challenge. There are logistic issues to consider. Myocardial infarctions are described as being anterior, inferior, or posterior, depending upon the location of the infarcted area of the heart muscle. Infarcts can be further classified as being transmural or non-transmural. A transmural infarct (Non Q-Wave MI) is one that involves damage to the full thickness of the myocardium. A nontransmural MI involves only a partial thickness of the muscle. In the majority of patients with AMI, chest pain is the major presenting symptom. The pain is usually substernal and may radiate to the neck, shoulders, arms, or epigastric area. The pain is described as heaviness, constriction, burning, or similar to indigestion. It is important to remember, however, that there may be little or no pain present at all. AMI can be very subtle, and often difficult to distinguish from ...