Pulse PDF - A Medical Lecture

Dr/ Heba Elfeky Objectives: At the end of this lecture the students should be able to:  Define pulse.  Discuss regulation of pulse.  Mention characteristics of pulse.  List factors affecting pulse rate, and mention its effect.  Locate pulse sites.  Define the following terms: Pulse deficit, t...

Dr/ Heba Elfeky Objectives: At the end of this lecture the students should be able to:  Define pulse.  Discuss regulation of pulse.  Mention characteristics of pulse.  List factors affecting pulse rate, and mention its effect.  Locate pulse sites.  Define the following terms: Pulse deficit, tachycardia, bradycardia, bigeminy, trigeminy, atrial fibrillation and ventricular tachycardia.  Mention how to assess pulse. Outlines:  Introduction.  Definition of pulse.  Physiology and regulation.  Characteristics of pulse.  Factors affecting pulse rate.  Assessment of pulse.  Pulse sites Heart conduction Cardiac cycle 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.  Tap felt in arteries caused by waves of blood forced through it by contraction of left ventricle. Pulse sites: Temporal Carotid Brachial Ulnar Radial Femoral Popliteal Posterior tibial Dorsalis pedis Physiology and regulation  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 excessive stretch of the aortic arch by an increase blood volume, sensory impulses travel to the cardiac center causing a reflex slowing of the heart rate through the parasympathetic nervous system. ↑ blood volume → ↓ HR ↓ blood volume → ↑ HR (as in hemorrhage). Cardiac out put  it is the amount of blood pushed by the ventricles /minute.  CO =SV x HR Stroke volume:  it is the amount of blood ejected /beat (70ml)  Heart Rate = 60- 100 B/M Characteristics of pulse  Rate or frequency  Rhythm or regularity  Volume or amplitude or strength. a. Rate:  Is the number of pulsations felt over artery per minute. 60-100 B/M  When assessing the pulse, the nurse must consider the variety of factors influencing pulse rate. Factors affecting pulse rate: (1) Age: Pulse rate decrease with increase in age. Age Heart rate (beats/min) Infants (1m. → 1yr.) 120-160/min. Toddlers (1yr. → 3yr.) 90-140/min. Preschool (3yr. → 6yr.) 80-110/min. School age (6yr. → 12yr.) 75-100/min. Adolescents → adult 60-100/min. (2) Sex:  Pulse rate in female slightly more than in male because female is much nervous than male till menopause. (3) Exercise and muscular activity:  Exercise and muscular activity increase pulse rate, while rest and sleep decrease pulse rate. 4) Temperature:  Pulse rate raises about 10 beats/min for every degree of temperature elevation. Also, prolonged application of heat increase pulse rate. (5) Stress and emotions:  Stress and emotions such as fear, anger, anxiety or surprise increase sympathetic stimulation which increases the overall activity of the heart. (6) Medications:  -Positive chronotropic drugs increase pulse rate such as atropine.  - Negative chronotropic drugs decrease pulse rate such as digitalis (lanoxin). (7) Hemorrhage:  Loss of blood increases sympathetic stimulation increasing pulse rate. 8) Position changes:  Pulse rate in standing or sitting position is higher than in lying down position. (9) Pulmonary conditions:  Any diseases causing poor oxygenation increase pulse rate. (10) Disease conditions:  Some diseases increase pulse rate such as infection, thyrotoxicosis, pulmonary embolism and anemia. Some diseases decrease pulse rate such as heart block. b. Rhythm  Pulse rhythm refers to the time intervals between each pulse beats.  Abnormal rhythm is called: (arrhythmia – dysrhythmia).  To document arrhythmia, a physician may order an electrocariogram (ECG). Pulse deficit  “The differences between the apical and radial pulse rates”.  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 assess radial and apical rates and then compare rates. c. Volume:  The volume of blood ejected against the arterial wall with each heart contraction  Normally, the pulse strength remains the same with each heart beat.  Pulse strength may be graded or described as normal, thready, weak or bounding.  A weak pulse: is the pulse which is difficult to palpate and easy to lose during palpation.  A normal pulse:is the pulse which is full, easily palpable and not easily obliterated by the assessor’s fingers.  A bounding pulse: is the pulse which is easily palpated and difficult to obliterate. Methods for pulse Assessment  b) Auscultation:  a) Palpation: a) Palpation The pulse is palpated with the tip of the middle three fingers of one hand. Light pressure is used to locate the area of strongest pulsation to count the rate, determine the rhythm and volume per minute. b) Auscultation:  Auscultation of apical pulse by a stethoscope provides the most accurate assessment of the pulse rate  It is useful when the peripheral pulses are difficult to assess or when the rhythm of the pulse is irregular. Stethoscope: Earpiece Binaural Tubing Bell Diaphragm Chest piece  Bowel, lung and heart sounds are osculated using the diaphragm.  Heart and vascular sounds are osculated using the bell Abnormalities of pulse: Tachycardia Is an abnormally elevated pulse rate, above 100 beat per minute in adults. Bradycardia: Is an abnormally slow pulse rate, below 60 beat per minute in adults. Pulsus bigeminus (bigeminy):  Premature beat (weak) alternate with normal sinus beat (strong). Pulsus trigeminus (Trigeminy): Premature beat alternate with two normal sinus beats Ventricular tachycardia: In which the pulse is weak (heart rate 150-250 beat per minute), discharging of impulses from hyperexcitable focus in the ventricles not from SA node. It is characterized by palpitation. Atrial fibrillation: In which the pulse is irregular, very weak to be felt at wrist, there is pulse deficit and palpitation. This condition due to discharging impulses from multiple excitable areas in atria which work separately with no coordination, but AV node and bundle of his can not conduct a very high rate of atrial excitation. Questions: Define pulse, pulse deficit, tachycardia, bradycardia, bigeminy, trigeminy, ventricular tachycardia, aterial fibrillation? Mention normal pulse rate? Identify factors that may affect pulse rate? List sites where the pulse is assessed, also describe how each pulse is located? Mention grades of pulse strength?