Blood Pressure – Nursing is a profession within the healthcare sector focused on the care of individuals, families, and communities so they may attain, maintain, or recover optimal health and quality of life. Nurses may be differentiated from other healthcare providers by their approach to patient care, training, and scope of practice. Nurses practice in many specialisms with differing levels of prescriber authority.
Many nurses provide care within the ordering scope of physicians, and this traditional role has shaped the public image of nurses as care providers. However, nurses are permitted by most jurisdictions to practice independently in a variety of settings depending on training level. In the postwar period, nurse education has undergone a process of diversification towards advanced and specialized credentials, and many of the traditional regulations and provider roles are changing.
Nurses develop a plan of care, working collaboratively with physicians, therapists, the patient, the patient’s family, and other team members, that focus on treating illness to improve quality of life. Nurses may help coordinate the patient care performed by other members of an interdisciplinary healthcare team such as therapists, medical practitioners, and dietitians. Nurses provide care both interdependently, for example, with physicians, and independently as nursing professionals.
Blood Pressure
Blood pressure is the pressure of the blood within the arteries. It is produced primarily by the contraction of the heart muscle.
or
Blood pressure is the lateral pressure exerted by the moving column of blood on the vessel wall per unit area by its contained blood while flowing through it.
Blood pressure: Cardiac Output × Peripheral resistant.
or
Blood pressure (BP) is the pressure of circulating blood on the walls of blood vessels. When used withou further specification, “blood pressure” usually refers to the arterial pressure in the systemic circulation.
Types of Blood Pressure:
Diastolic pressure:
It is the lowest pressure observed in the aorta during diastole.
Or
It is the lowest arterial pressure during a cardiac cycle. It is measured when the heart is relaxed (diastole) and blood is returning to the heart via the veins. 05-31778) are bold stat Normal diastolic pressure is about 60-90 mm Hg.
Significance:
- It is the measure of peripheral resistance.
- It is the level at which the heart is pumping. If the diastolic pressure is raised, heart is doing 10 more work.
Systolic pressure:
It is the maximum arterial pressure during systole.
Or
It is the highest arterial pressure during a cardiac cycle. Systolic pressure is measured after the heart contracts and blood is ejected into the arterial system.
- Normal systolic pressure is about 110 to 140 mm Hg.
Significance:
The height of systolic pressure indicates-
- The force of contraction of the heart.
- The extent of work has done by the heart
- The degrees of pressure, which the arterial walls, have to withstand.
Pulse pressure:
It is the difference between systolic pressure and diastolic pressure. The most determinant of pulse pressure is stroke volume. As blood is ejected from the left ventricle into the arterial system, arterial pressure increases because of the relatively low capacitance of the arteries. Because diastolic pressure remains unchanged during ventricular systole, the pulse pressure increases to the same extent as systolic pressure.
Normal pulse pressure is about 30 to 40 mm Hg.
Significance:
- It is the index of cardiac output. e.g. ↑Cardiac output ↑ Pulse pressure
- When the capacitance (distensibility of blood vessels) of arteries decreases (in aging process), pulse pressure increases.
Purposes of Measuring Blood Pressure:
1. To determine patients’ blood pressure as a baseline for comparing future measurements
2. To aid in diagnosis
3. To aid in the assessment of cardiovascular system preoperatively and postoperatively, during and after invasive procedures
4. To monitor change in condition of the patient
5. To assess response to medical therapy
6. To determine patients hemodynamic status.
Importance of Blood Pressure
A. It is essential for the flow of blood through the circulatory tree.
B. It provides motive force for filtration at the capillary bed which is essential for-
a) Tissue nutrition
b) Formation of urine
c) Formation of lymph
d) For venous return.
Physiological Variation of Blood Pressure
1. Age:
2. Sex: In female, the blood pressure is slightly lower (5 mm of Hg), cause is unknown, after 22nolingi menopause, it reaches male level.
3. Build: The systolic pressure is usually high is an obese person.
4. Exercise: In strenuous exercise, the systolic pressure raises, even up to 180 mm of Hg. In moderate exercise, it slightly rises. The diastolic pressure is usually lower.
5. Posture: During standing, diastolic pressure slightly higher, systolic pressure lower. In recumbent position, this condition is reversed.
6. Diurnal variation: During day time, pressure rise up to 2-0 clock and then there is a slight fall. In W. case of night workers, the blood pressure raises during morning.
7. During sleep: During deep sleep, there is fall of blood pressure by 15-20 mm of Hg.
8. After meal: Blood pressure is raised during digestion due to increase cardiac output up to 20 mm of Hg
9. Emotion and excitement: Raises systolic pressure considerately
10. Respiration: There are fluctuations of blood pressure due to variations in stroke volume and peripheral resistance.
At a normal respiratory rate, the blood pressure falls during most part of inspiration. At a slower OT respiratory rate, the blood pressure is slightly higher during inspiration.
Factors Influencing Blood Pressure:
A. Peripheral resistance: Increase peripheral resistance increases blood pressure. It depend on-
a) Elasticity of arterial wall
b) Velocity of blood
c) Viscosity of blood
d) State of vessel lumen.
B. Cardiac output: It increases blood pressure. It depends on heart rate and stroke volume. Stroke volume again depends on
a) End systolic volume:
- Force of contraction
- Peripheral resistance
b) End diastolic volume:
- Venous return
- Diastolic period.
- Contraction of heart
C. Age: Blood pressure raises with age
D. Sex: 10% less in female
E. Posture: In recumbent position blood pressure is lower than in standing or sitting posture.
F. Exercise: It increases blood pressure.
Factors Controlling Blood Pressure:
The factors that maintain blood pressure may conveniently be discussed under two main headings-
A. Cardiac output: Cardiac output depends upon-
a) Blood volume
b) Venous return
c) Force of contraction of heartle
d) Frequency of heart beat.
B. Peripheral resistance: Peripheral resistance depends upon-
a) Elasticity of arterial wall
b) Velocity of blood
c) Viscosity of blood
d) State of lumen of blood vessel.
Q. A young man having blood pressure 120/70 mm Hg, What will his pulse pressure and mean arterial blood pressure. Give the significance of mean blood pressure?
Answer.
Here,
The systolic pressure of the young man is 120 mmHg and diastolic is 70mmHg.
We know that, pulse pressure = Systolic pressure -Diastolic pressure,
= 120 mm Hg -70 mm Hg = 50 mm Hg
And, the mean pressure = Diastolic pressure + 1/3 of the pulse pressure
= 70+1/3 (x 50)
= 70+50/30
= 86.66 mmHg.
So, the pulse pressure of the young man is 50 mm Hg. and the mean pressure is 86.66 mmHg.
Significance of mean blood pressure:
- It is helpful to flow of blood in different organs.
- ↑ Mean pressure causes hypertension.
Q. What should be the blood pressure of a 35 years man? Name the different factors that influence/control/regulate this pressure.
Answer.
The normal blood pressure of a 35 years man is average 120/80 mm of Hg
Factors influence/control/regulate blood pressure:
➤ Peripheral resistance: ↑ TPR – ↑ TBP
➤ Cardiac output: ↑Cardiac output ↑ BP.
➤ Age: BP rises with age (both systolic & diastolic).
➤ Sex: BP is 10% less in female. Lonid
➤ Posture: In the recumbent position, BP is lower than in standing or sitting position.
➤ Exercise: It increases BP
➤ Body weight:↑Body weight Body surface area →↑CO↑ BP
➤ Emotion & Excitement: ↑ Sympathetic discharge ↑CO→↑BR
➤ Sleep: BP falls about 15-20 mm of Hg during sleep
➤ Exposure to cold: ↑ BP.
➤ Respiration: BP varies with respiration.
➤ Meals: BP slightly ↑ after meals.
Q. Why blood pressure increases in old age, exercise and in pregnancy? (For Viva)
Answer.
A) In old age: BP increases due to –
- Atherosclerotic change in the artery & its wall become thick.
- Artery become stiff & its elasticity decreases.
B) In exercise: BP increases due to
- ↑ Venous return.
- ↑Metabolic activity & Oxygen demand.
- ↑ Heart rate & Cardiac output due to ↑ venous return.
c) In pregnancy: Blood volume (hemodilution) → ↑CO→↑ BP
Q. Which one is more important, Systolic or Diastolic pressure? (For Viva)
Answer.
Diastolic pressure is the level at which the heart is pumping blood.
If the diastolic pressure is increased
↓
Heart will have to do more work
↓
Heart may be hypertrophied, may lead to heart failure.
Measuring Method of Blood pressure:
A. Direct method: The artery is exposed and an arterial cannula of which one end is inserted directly into the lumen of the exposed vessel and the other end is connected to the U shaped mercury manometer that show the actual blood pressure in mm of Hg.
B. Indirect method:
a) Oscillatory.
b) Palpatory: Can measure only systolic pressure.
c) Auscultatory: Can measure both systolic and diastolic pressure.
Significant of Blood Pressure:
A. Systolic pressure: it includes-
a. The extent of work done by heart.
b. The force with which the heart is working
c. The degree of pressure which the arterial walls have to withstand
d. It is increase during excitement, exercise, meals etc
e. It decrease while sleep rest, etc
B. Diastolic pressure:
a. It indicates the constant load against which the heart works
b. Increased diastolic pressure indicates that heart is approaching to failure.
c. It is the index of peripheral resistance.
C. Pulse pressure: It indicates the cardiac output.
D. Mean pressure: Mean pressure is the driving force for blood flow. It depends on cardiac output and peripheral resistance.
Causes to Increase Blood Pressure in Old Age, Exercise and Pregnancy:
A. In old age: Blood pressure increase due to-
- Athero-sclerotic change in the artery and its wall become thick.
- Artery become stiff 7 its elasticity decreases.
B. In exercise: Blood pressure rises due to
- Increased venous return.
- Increased metabolic activity & much energy & O₂ is required
- Increased heart rate and cardias output due to increased venous return.
C. In pregnancy: Blood volume both plasma and corpuscles increase which increases cardiac output thus blood pressure is raised.
Procedure of Monitoring Blood Pressure:
A. Articles Required for Measuring Blood Pressure:
a) A sphygmomanometer comprising of
- Compression bag or inflatable rubber enclosed in a cloth cuff (appropriate size)
- An inflating bulb (by which pressure is raised)
- A manometer from which pressure is read.
- A screw type release valve for inflation and deflation (pressure control).
b) ) Stethoscope
c) Patient chart for reading
d) Black or blue pen for charting.
B. Procedure
1. Check physician order nursing care plan and progress notes.
2. Explain the procedure and reassure the patient. Ensure that patient has not smoked, ingest caffeine or involved in strenuous physical activity within 30 minutes prior to procedure.
3. Wash and dry hands.
4. Assist the patients either sitting or lying down position
5. Collect and check equipment
6. Position the sphygmomanometer at approximately heart level of the patient ensuring that mercury level is at zero.
7. Select a cuff of appropriate size 8. Expose the arm to make sure that there is no constructive clothing above the placement of cuff.
9. Apply the cuff approximately 2.5 cm above the point where brachial artery can be palpated. The cuff should be applied smoothly and firmly with the middle of the rubber bladder over the artery.
10. Secure the cuff by tucking the end under or by fixed the Velcro fastener.
11. Place the entire arm at the patient heart level
12. Keep the arm well rested and supported.
13. Place yourself in a comfortable position
14. Connect the cuff tubing to the manometer tubing and close the valve of the inflation bulb.
15. Palpate the radial pulse and inflate the cuff until pulse is obliterated.
16. Inflate the compression bag a further 20-30 mm of Hg and then deflate cuff slowly. Note the point which pulse reappears. Release the valve.
17. Palpate brachial artery and place diaphragm of the stethoscope lightly over the brachial artery. Ensure that ear piece of the stethoscope are placed correctly. Raise mercury level 20-30mm of Hg above the point of systolic pressure often by means of palpatory method.
18. Release the valve of the inflation bulb, so that mercury column falls at the rate of 2-3 mm of Hg per second.
19. When first sound is heard, the mercury level is noted, this denotes systolic pressure
20. Continue to deflate the cuff. When the sound disappears note the mercury level. This is diastolic pressure.
21. Deflate cuff completely. Disconnect the tubing and remove the cuff from the patients arm wend
22. Repeat the procedure after one minute there is any doubt about the reading
23. Ensure that patient is comfortable
24. Remove equipment and clean ear piece with a spirit swab.
25. Wash and dry hands 26. Documents the reading in appropriate observation chart or flow chart
27. Report any abnormal findings.
Special Precaution Should Be Taken During Measuring Blood Pressure:
1. Do not take blood pressure on a patient’s arm if
- the arm has an intravenous infusion on it
- The arm is injured/diseased
- The arm has a shunt/fistula for renal dialysis.
- On the same side if the patient had a redial mastectomy.
- If the arm is paralyzed.
2. Always check supine measurement before checking upright measurement.
3. If blood pressure has to be taken at the same time in two or more position-lying, sitting or standing at the same time for comparison, wait for a minimum of 3 minutes after assuming that position before taking the reading.
4. If comparison is need for blood pressure in lying/standing position, the patient must be in laying/ standing position for a minimum of three minutes.
5. Appropriate sized cuff should be used.
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