Explain how these Pathological variations affect cardiac output.
1.) Fever
2.) Anemia
3.) Hyperthyroidism
4.) Atrial fibrillation
5.) Shock
6.) Haemorrhage
Answers
Explanation:
1)Resolution of fever was associated with a 23% increase in stroke volume index (SVI) and 37% increase in left ventricular stroke work index (LVSWI) for group I (p less than 0.01). Group II showed a 27% increase in SVI and a 38% increase in LVSWI (p less than 0.05).
2)Anemia increases cardiac output, may lead to eccentric left ventricular hypertrophy, activation of the sympathetic nervous system, and stimulation of the renin angiotensin aldosterone system, and is closely associated with chronic inflammation and increased oxidative stress.
3)Hyperthyroidism causes a hyperdynamic circulation, characterized by increased cardiac contractility and heart rate, increased preload, and decreased systemic vascular resistance (SVR), resulting in significantly increased cardiac output.
4)Atrial fibrillation may have hemodynamic consequences. It can decrease cardiac output due to ineffectual atrial systole and increase pulmonary venous pressure resulting in heart failure.
5)Early in septic shock, the rise in cardiac output is often limited by hypovolemia and a fall in preload because of low cardiac filling pressures. When intravascular volume is augmented, the cardiac output usually is elevated (hyperdynamic phase of sepsis and shock).
6)The reduction in blood volume during acute blood loss causes a fall in central venous pressure and cardiac filling. This leads to reduced cardiac output and arterial pressure.