Cardiac Output O2 Saturation Capillary Refill M.rich, RN, BSN

Bell Work 3-7-18 1. What Cardiac Diagnostic procedures discussed would require a patient to refrain from eating/drinking for a certain time period? 2. What are the atrioventricular valves? 3. What heart valve would prevent backflow of blood into the Right Atrium? 4. The T wave in the PQRST represents what in the cardiac conduction system? 5. What is the normal range for O2 saturation?

Standard 31. Assess and analyze cardiac output and tissue perfusion using capillary refill and/or pulse oximeter by assessing multiple classmates and correctly charting on flow chart.

Objectives By the end of class, students will be able to: Identify the meaning of Cardiac Output Assess Capillary Refill Understand 02 Saturation and the normal range

What is Cardiac Output (CO) the amount of blood pumped by the heart per minute CO = HR X SV usually expressed in liters/minute Stroke volume = amount pumped per beat

Heart Rate (HR) Heart rate is directly proportional to cardiac output Adult HR is normally 60-100 beats per minute (bpm.)  Heart rate is modified by autonomic, immune, and local factors.  For example: An increase in parasympathetic activity in the heart will decrease the heart rate. An increase in sympathetic activity throughout the heart will increase the heart rate.

Stroke Volume (SV) SV = EDV - ESV Is determined by three factors: preload, afterload, and contractility.  Preload gives the volume of blood that the ventricle has available to pump also called End-Diastolic Volume. Afterload is the arterial pressure against which the muscle will contract or End-Systolic Volume Contractility is the force that the muscle can create at the given length   These factors establish the volume of blood pumped with each heart beat. 

Cardiac Volumes SV = end diastolic volume (EDV) - end systolic volume (ESV) EDV = amount of blood collected in a ventricle during diastole ESV = amount of blood remaining in a ventricle after contraction

Preload

afterload

Cardiac Output Explained https://www.youtube.com/watch?v=vFRkSB46bl8

Cardiac Output Monitoring Pulmonary Artery Catheter – Invasive but most accurate a catheter that has an inflatable balloon at its tip. Inserted through a large vein and moved to the right atrium. It is then moved on through the right ventricle and out through a pulmonary artery. The balloon is inflated and its wedged into a small pulmonary blood vessel. Gives info about pressure in the right side of the heart and in the arteries of the lungs. Blood samples can also be taken at various sites within the heart to understand blood oxygen flow.

O2 Saturation Measured in percent using a pulse oximeter Normal Range 94-100% for healthy adults Breathing room air contains 21% oxygen. Anyone who is not achieving the critical blood oxygen saturation level of 90% may need oxygen

O2 Sat Non invasive process involves inserting a finger (can be used on the ear or a toe as well) into the device where a red light calculates the redness of the blood pulsing through the finger. 

O2 Saturation Oxygen saturation levels measure the degree to which the hemoglobin contained in the red blood cells (erythrocytes) has bonded with oxygen molecules. Oxygen is taken in by the lungs when we breathe in

Factors that May Influence an Sp02 Reading If you have poor circulation and/or cold hands. If you wear nail polish or artificial nails. If you’re shivering or your hands are trembling. If you have heart arrhythmias. If you smoke.

Tips for Getting a Better Reading Make sure the probe is functioning properly and that it’s securely attached to the finger. If you’re having difficulty getting a reading, try another finger or the opposite hand. Warm your hands by placing them inside a warm towel or under warm, running water. Remove nail polish or artificial nails. Don’t smoke.

Capillary Refill Pressure is applied to the nail bed until it turns white. This indicates that the blood has been forced from the tissue. It is called blanching. Once the tissue has blanched, pressure is removed. While the patient holds their hand above their heart, the health care provider measures the time it takes for blood to return to the tissue. Return of blood is indicated by the nail turning back to a pink color. If there is good blood flow to the nail bed, a pink color should return in less than 2 seconds after pressure is removed.

Capillary Refill Test Used to monitor dehydration and the amount of blood flow to tissue. Measures how well the vascular system works in your hands and feet -- the parts of your body that are farthest from the heart. https://www.youtube.com/watch?v=U-oSBEx6ZSM

Review WHAT IS CARDIAC OUTPUT?

the amount of blood pumped by the heart per minute CO = HR X SV

What is the normal ranges for O2 Saturation?

94-100%

How do you perform Capillary Refill Test and for how long?

Pressure is applied to the nail bed until it turns white Capillary Refill Pressure is applied to the nail bed until it turns white a pink color should return in less than 2 seconds after pressure is removed.

Midterm Review Comprehensive 50 m/c, 35 questions on Heart, 15 (comprehensive)