Cardio Vascular System Cardiac Output Blood Pressure Youtube Lecture Handouts
Definition It is the amount of blood pumped out by each ventricle in one minute. Also called minute volume Normal value- 5 lit/min Cardiac Index is cardiac output per square meter of body surface area. It is 3L/m2 /min in adult weighing 70 kg.
Stroke Volume Definition- Is output per ventricle per beat Normal value = 70 ml/ beat Stroke vol. Index- Is volume per square meter of body surface area & is ~ 47ml. Distribution of Cardiac Output Distribution of Cardiac Output Table Body organ Blood flow ml/min Liver 1500 Kidney 1300 Brain 750 Lungs 500 Heart 250 OrganBloodflow Skeletalmusc.+Otherorgans1000 Skin500 About 75% goes to liver, kidney, brain, lungs & heart. i.e. to the vital organs. Rest 25%goes to other organs Cardiac Reserve Is the maximum amount of blood that heart can pump. It is physiological limit of heart Normal value= 30 to 40 L/min during exercise Control of Cardiac Output Cardiacoutput=HRxSV NormalHR=70beats/min Strokevolume=70ml/beat Cardiacoutput=70X70=4900ml/minorabout5L/min Factors 1. Heart rate 2. Force of contraction 3. Venous return 4. Peripheral resistance