Pulse – Vital sign/Cardinal Sign. Characteristics of the Pulse and Equipment Used – simple nursing guide.
AUTHOR : LEENA ANLET
Vital Signs are a basic component of assessment of physiological and psychological health of a client. Body temperature, pulse, respiration and blood pressure are the signs of life. Assessment of vital signs allows the nurse to:
1. Identify specific life threatening conditions and plan the needing nursing interventions.
2. Detect changes in the client’s health status.
Vital signs/cardinal signs in a normal healthy individual remain constant. They are called “vital signs” because of the following reasons:
1. These findings are governed by vital organs and often reveal even the slightest deviation from the normal body functions.
2. The changes in the condition of the client, improvement or regression may be detected by the observation of these signs.
3. Significant variations in these findings may indicate problems relating to insufficient consumption of oxygen, blood depletion, electrolyte imbalance, bacterial invasion and other problems.
4. Through these signs, specific information may be obtained that will help in the diagnosis of disease, the result of treatment, medications and nursing care.
5. Even the client’s emotional state may also cause a significant variation in the symptoms.
The normal body temperature is 37 degree celcius in adults
The normal pulse is 72/minute in adults
The normal blood pressure is 120/80 mm of Hg in adults
Pulse is an alternative expansion (rise) and recoil (fall) of an artery as the wave of blood is forced through it during the contraction of the left ventricle. The pulse can be felt by the fingers on a point where the artery crosses a bone close to the surface of the skin.
When the left ventricle contract, if forces about 70 ml of blood into the aorta and into the arteries. The walls of the arteries being elastic, expand as an added amount of blood is forced into them. The arteries relax as the wave of blood passes, only to expand again with the next wave of blood. This expansion and recoil of arteries is the pulse and serves as an indication of the frequency of the heart rate.
The pulse may be felt at:
1. Radial artery in front of the wrist.
2. Temporal artery over the temporal bone
3. Carotid artery at the sides of the neck
4. The brachial artery above the elbow and in the antecubital fossa (inner part of the elbow)
5. Femoral artery in the groin
6. Poplitial artery in the poplitial fossa (back of the knee)
7. The dorsalis pedis artery on the foot.
8. The posterior tibial artery behind the medial malieolus
The apical pulse is palpated in count the pulse rate in infants.
Characteristics of the Pulse
Before assessing the pulse, nurse must be familiar with the normal characteristics of a pulse – the rate, rhythm, volume and tension.
Rate is the number of pulse beats in a minute. The normal rate in the resting adult is 60 to 100 per minute. A pulse rate over 100 per minute is referred to be “tachycardia”. A pulse rate below 60 per minute in an adult is referred to be “bradycardia”.
The factors causing variations in pulse rate are:
Age: the very young have a rapid pulse rate. The adults have a normal range of 70 to 80 per minute. The very old have relatively slow pulse rate.
Before birth (F.H.S) – 140 to 150 per minute
At birth (newborn) – 130 to 150 per minute
First year – 115 to 130 per minute
Second year – 100 to 113 per minute
Third year – 90 to 100 per minute
4 to 8 years – 86 to 90 per minute
8 to 15 years – 80 to 86 per minute
Adult – 70 to 80 per minute
Old age – 60 to 70 per minute
Sex: the female has a slightly more rapid pulse than the male.
Physique: the short person with small body build has a slightly more rapid pulse than the tall heavy individual.
Exercise: increased muscular activity will increase the pulse rate.
Food: indigestion of food causes a slight increase in the pulse rate for several hours.
Posture: the pulse rate is higher when the body is in standing position than when in sitting or reclining position.
Emotions: mental or emotional disturbances will increase pulse rate temporarily.
Application of heat: application of heat can increase the pulse rate.
Pain: a client in the agony of pain will have increased pulse rate.
Increased body temperature: when the body temperature is elevated the pulse rate tends to rise.
Disease conditions: loss of blood, injury to the viscera, shock etc., increase the pulse rate. Heart diseases, typhoid, infection etc., have a marked effect on the pulse rate. In heart diseases, the pulse rate may be either rapid or slow according to the type of cardiac lesions. In typhoid fever, the pulse rate tends to be slow.
Drugs: stimulant drugs e.g., caffeine, atropine, thyroid, adrenaline etc., will raise the pulse rate. Administration of sedative drugs can reduce the pulse rate.
Cold applications: the cold applications can reduce the pulse rate. Hypothermia can reduce the pulse rate to a very lower rate.
Rhythm refers to the regularity of beats. Normally the heart beats are spaced at equal intervals and they are said to be regular. When the interval varies between the beats it is said to be irregular. If an irregularity is present, the pulse should be counted for one full minute.
The abnormal rhythm in the pulse is seen in the following conditions.
Arrhythmias: it is a technical term that indicates any variation from normal rhythm.
Intermittent pulse: it is one in which the beats are missed at regular intervals. In intermittent pulse, there is a difference between the apical and the radial pulse. It is known as pulse deficit.
Extrasystoles: when the cardiac contractions occur prematurely, i.e. before they are normally due in the cardiac cycle, it is called extrasystolic pulse.
Atrial fibrillation: rapid contractions of the atrium causing irregular contractions of the ventricles in both rhythm and force.
Ventricular fibrillation: it is the rapid twitching of the ventricles. It is fatal.
Sinus arrhythmia: it is a condition in which the pulse rate is rapid during inspiration and slow during expiration.
Dicrotic pulse: there is one heart beat and two arterial pulsations giving the sensation of a double beat.
Volume refers to the fullness of the artery. It is the force of the blood felt at each beat. Volume depends upon the amount of blood in the arteries. If the arteries contain a normal volume of blood, the pulse is said to be full or large in volume.
If the volume of the blood is decreased by haemorrhage, the pulse will be weak, thereby, small feeble or flickering. When the pulse is large or full and also rapid in rate, it may be described as bounding pulse.
The abnormal volume of pulse will be seen in the following:
Water hammer pulse or Corrigan’s pulse or collapsing pulse:
It is a full volume pulse but rapidly collapsing pulse occurring in aortic regurgitation or incompetence, where the blood having been forced into the artery by the ventricular contraction, regurgitates back into the ventricle, owing to the non closure of the aortic valve.
It signifies an increased stroke volume as seen in exercises, anxiety, anaemia, hepatic failure, heart block and the water hammer pulse.
The rhythm is regular but the volume has an alternative strong and weak character. This may be noticed in the left ventricular failure, heart block and digitalis toxicity.
It is accompanied by an irregular rhythm in which every other beat comes early. The second or premature beat feels weak due to inadequate filling of the ventricles between the two beats. It may be so weak that it fails to produce a palpable peripheral pulse (pulse deficit). It is seen in myocardial infarction and digitalis toxicity.
A small weak pulse that feels like a wire or thread on the palpation of arteries. It signifies a decreased stroke volume and is seen in haemorrhagic shock or loss of fluid from the body. E.g. diarrhea and vomiting.
In this case the force or strength of the pulse wave varies, feeling weaker when the client takes in a breath. During inspiration, less blood is returned to the left side of the heart, reduces the stroke volume and therefore decreases the strength of the pulse. This may occur normally, but if pronounced this may indicate cardiac damage.
Tension is the degree of compressibility. It is said to be high tension when the artery is difficult to compress and low tension when it is easy to compress.
Frequency of Taking Pulse
The pulse is taken along with the body temperature twice a day for clients who are not seriously ill. It may be taken frequently for clients who has surgeries, accidents or who are critically ill. Frequency depends upon the condition of the client and also according to the doctor’s orders. (In hyperthyroidism the sleeping pulse may be recorded)
Auscultation of the apical pulse requires a stethoscope. The stethoscope should have snugly fitting ear pieces and thick walled tubing about 12 inch long for optimal sound transmission. The stethoscope should have a bell and a diaphragm.
Peripheral pulse that cannot be detected by palpation may be assessed with an ultrasonic Doppler service. Place the transmitter of the device over the artery to be assessed. High frequency waves directed at the artery from the transmitter are disturbed by the pulsating flow of blood and are reflected back to the ultrasound device. The sound disturbances are amplified and heard through ear pieces or a speaker attached to the device.
Uses of Doppler for assessment of pulse:
To determine the adequacy of blood flow to an area when occlusive vascular disease threatens the blood supply.
For post operative assessment where peripheral circulation can be occluded.
In cardiopulmonary collapse where peripheral vasoconstriction makes pulse difficult to palpate.
In obesity, or oedema, which makes palpation difficult
Method of Taking Pulse
Palpation is done using the first and second or second and third fingers of one hand. Use light pressure at first, in order to locate the area of strongest pulsation. After this, more forceful palpation is done to count the rate, determine the rhythm and assess the quality of pulsation.
The most accurate assessment of pulse rate is the apical pulse, and the apical pulse is assessed by placing the diaphragm of the stethoscope over the apex of the heart. The sound heard is due to the opening and closing of the cardiac valves. The apical pulse should be counted for one full minute.