Pulse PDF - Zeinab Hussein Bakr

# Pulse Dr Zeinab Hussein Bakr ## Introduction - The stimulus for conduction of the heart normally starts as an electrical impulse in the sinoatrial (SA) node of the right atrium. - In adults, the SA node initiates the impulse 60-100 times per minute. The electrical impulse then spreads quickly th...

# Pulse Dr Zeinab Hussein Bakr ## Introduction - The stimulus for conduction of the heart normally starts as an electrical impulse in the sinoatrial (SA) node of the right atrium. - In adults, the SA node initiates the impulse 60-100 times per minute. The electrical impulse then spreads quickly through the conduction system to the remainder of the heart so that the heart muscle fibers contract in a synchronous fashion. ## Definitions of Pulse: - Waves of blood forced through arteries by contraction of the left ventricle. - Waves of blood created by alternating expansion and recoil of arteries during each cardiac cycle. ## Physiology and Regulation: - The blood flows through the body in a continuous circuit. The cardiac centers located in the medulla of the brain stem control the heart through sympathetic or parasympathetic innervations. - The cardiac centers speed up or slow down the heart rate in response to sensory impulses from the heart. For example, if there is an excessive stretch of the aortic arch due to an increase in blood volume, sensory impulses travel to the cardiac center, causing a reflex slowing of the heart rate through the parasympathetic nervous system. ## Stroke Volume (SV): - It is the amount of blood ejected per beat (70 ml). ## Cardiac output (CO): - It is the amount of blood pushed by the ventricles per minute. - CO = SV x HR - ↑ blood volume → ↓ HR - ↓ blood volume → ↑ HR (as in hemorrhage). - The heart functions to maintain a relatively constant circulatory blood flow (approximately 70 to 72 ml of blood enters the aorta with each ventricular contraction (stroke volume)). With each stroke volume ejection, the walls of the aorta distend, creating a pulse wave that travels rapidly toward the distal ends of the arteries. When a pulse wave reaches a peripheral artery, it can be palpated by passing the artery lightly against underlying bone or muscle. ## Characteristics of Pulse: - Characteristics of pulse include: rate or frequency, rhythm or regularity, and volume or amplitude or strength. ### Rate: - Is the number of pulsations felt over the artery per minute. - When assessing the pulse, the nurse must consider the variety of factors influencing the pulse rate. ## Factors affecting pulse rate: - **Age** - **Sex**: Pulse rate in females is slightly more than in males because females are more nervous than males until reaching menopause. - **Exercise and Muscular Activity**: Exercise and muscular activity increase pulse rate, while rest and sleep decrease pulse rate. - **Temperature**: Pulse rate raises about 10 beats/min for every degree of temperature elevation. Prolonged application of heat increases pulse rate. - **Stress and Emotions**: Stress and emotions such as fear, anger, anxiety, or surprise increase sympathetic stimulation, which increases the overall activity of the heart. - **Medications**: - Positive chronotropic drugs increase the pulse rate such as atropine. - Negative chronotropic drugs decrease the pulse rate such as digitalis (lanoxin). - **Hemorrhage**: Loss of blood increases sympathetic stimulation, increasing the pulse rate. - **Position Changes**: The pulse rate in standing or sitting position is higher than in lying down position. - **Pulmonary Conditions**: Any diseases causing poor oxygenation increase the pulse rate. - **Disease Conditions**: Some diseases increase the pulse rate such as infection, thyrotoxicosis, pulmonary embolism, and anemia. Some diseases decrease the pulse rate such as heart block. ### Rhythm: - Pulse rhythm refers to the time intervals between each pulse beat. - Normally, the pulse has a regular rhythm or equal intervals of time between beats. When an interval is interrupted by an early or late or missed beat, this creates an abnormal rhythm (arrhythmia - dysrhythmia). - To document arrhythmia, a physician may order an electrocardiogram (ECG). - An inefficient contraction of the heart that fails to transmit a pulse wave to the peripheral pulse site creates a “pulse deficit”. To assess a pulse deficit, the nurse assesses the radial and apical rates and then compares the rates. - **Pulse Deficit**: "The differences between the apical and radial pulse rates". ### Volume: - The strength of a pulse reflects the volume of blood ejected against the arterial wall with each heart contraction and the condition of the arterial vascular system leading to the pulse site. - Normally, the pulse strength remains the same with each heartbeat. - Pulse strength may be graded or described as normal, thready, weak, or bounding. ## Methods for Pulse Assessment: ### Palpation: - The pulse is palpated with the tips of the middle three fingers of one hand. Light pressure is used to locate the area of the strongest pulsation to count the rate, determine the rhythm, and volume per minute. ### Auscultation: - Auscultation of the apical pulse by a stethoscope provides the most accurate assessment of the pulse rate and is useful when the peripheral pulses are difficult to assess or when the rhythm of the pulse is irregular. - **Stethoscope**: The 4 major parts of the stethoscope are: the earpiece, binaural, tubing, and chest piece. The chest piece consists of a bell and a diaphragm. ## Pulse Sites: - The image depicts several pulse points and pressure points on the body. These include: - External Maxillary - Superficial Temporal - Carotid - Brachial - Ulnar - Radial - Femoral - Popliteal - Dorsalis Pedis ## Abnormalities of Pulse: - **Tachycardia**: An abnormally elevated pulse rate (above 100 beats per minute) in adults. - **Bradycardia**: An abnormally slow pulse rate (below 60 beats per minute) in adults. - **Pulsus Bigeminus (Bigeminy)**: Premature beat (weak) alternates with normal sinus beat (strong). - **Pulsus Trigeminus (Trigeminy)**: Premature beat alternates with two normal sinus beats. - **Ventricular Tachycardia**: In which the pulse is weak (heart rate 150-250 beats per minute), discharging of impulses from hyper-excitable focus in the ventricles, not from the SA node. It is characterized by palpitation. - **Atrial Fibrillation**: In which the pulse is irregular; very weak to be felt at the wrist; there is a pulse deficit and palpitation. This condition is due to discharging impulses from multiple excitable areas in the atria which work separately with no coordination, but the AV node and bundle of his cannot conduct a very high rate of atrial excitation.