SUBARACHNOID HAEMORRHAGE

Subarachnoid Haemorrhage

Subarachnoid Haemorrhage

Circulation (C)

Circulation problems may be caused by primary heart disease such as myocardial infarction, heart block and some drugs. The most common cause of cardiac arrest is an arrhythmia caused by myocardial ischaemia or infarction. Circulation problems may also be the result of heart abnormalities secondary to other problems such as airway obstruction or apnoea, tension pneumothorax or severe blood loss. Cardiac function will also be impaired in hypothermia, severe septic shock, hypoxia and anaemia. (Wood Hyman Wood 2007 pp.132-136)

Blood pressure

The most common circulation problem in the surgical setting is hypovolaemia caused by bleeding and should be considered the primary cause of shock until proven otherwise. CT angiography (CTA) may be performed to determine the source of hemorrhage. A minimally invasive test, CTA uses a timed bolus of intravenous (IV) contrast to visualize the arteries. (Gold Cullinane Chen Oliver Landry 2005 pp.249-52)

As a outcome of the bleeding, the body issues large allowances of adrenaline and alike hormones. This directs to a pointed boost in the body-fluid pressure; the heart arrives under considerable damage, and neurogenic pulmonary edema (accumulation of fluid in the lungs), cardiac arrhythmias (irregularities in the heart rate and rhythm), electrocardiographic alterations (in 27% of cases) and cardiac apprehend (in 3% of cases) may happen quickly after the onset of hemorrhage. (Gold Cullinane Chen Oliver Landry 2005 pp.249-52)

Vasoactive drugs

Vasodilator pharmaceuticals are now accessible which can expressly 'target' distinct sites in the circulation. Some pharmaceuticals, for example hydralazine, use their prime consequences on the arterial capacitance vessels - decreasing both afterload and body-fluid pressure. In compare, nitroglycerine (glyceryl trinitrate) actions predominantly as a venodilator and decreases preload while having little effect on afterload. Sodium nitroprusside is a powerful, 'mixed', vasodilator which reliably decreases both afterload and preload. Drugs for example nitric oxide and adenosine, ...