INTERPRETATION OF VITAL SIGNS

Transcription

1 DIALYSIS MENTOR- DPSI-008/2011 INTERPRETATION OF VITAL SIGNS BY P.DAVID BALU G.PADMA PRABAKAR DIALYSIS PERSONNEL SOCIETY OF INDIA

2 INTERPRETATION OF VITAL SIGNS VITAL SIGNS: Systemic inner vital organs are continuously working to keep us healthy until our life time. The functions of vital organs can be measured by Blood pressure, pulse, respiratory rate, and body temperature. These functional signs are otherwise called vital signs. Abnormalities of vital signs are often clues to disease and alterations in vital signs are used to evaluate a patients progress. BLOOD PRESSURE: Blood pressure is the force or pressure which the blood exerts on the walls of the blood vessels. There are four terms are in common use in BP. SYSTOLIC BLOOD PRESSURE: When the left ventricle contracts and pushes blood into the aorta the pressure produced within the arterial system is called the systolic blood pressure. In adult it is about 120mmhg. DIASTOLIC BLOOD PRESSURE.: When complete cardiac diastole occurs and the heart is resting following ejection of blood, the pressure within the arteries between the contractions of the heart is called Diastolic Blood Pressure. In adult it is about 80mmhg. PULSE PRESSURE; The pressure difference between systolic and diastolic is called the pulse pressure. MEAN ARTERIAL PRESSURE It is roughly the arithmetic mean of Diastolic and systolic pressure.

3 Blood pressure vary according to the time the day, the posture, gender and age of the individual. During bed rest and night the BP tends to be low. It increases with age and usually higher in women than in men. FACTORS CONTROLLING BLOOD PRESSURE In the normal resting person, the blood pressure is steadily maintain with in narrow limits by cardiac output peripheral resistance, elasticity, blood volume, vasomotor center and hormonal influences. CARDIAC OUTPUT The volume of blood expelled by the ventricles of the heart with each beat multiplication by the heart rate. A normal, resting adult has a cardiac output of 4-8 l/mt. The cardiac output is determined by the stroke volume and the heart rate. Stroke volume means the output by ventricle per beat. In adults the average stroke volume is 70ml/beat. An increase in cardiac output raises systolic and diastolic blood pressure. An increase in stroke volume increases systolic pressure more than it does diastolic pressure. PHERIPHERAL RESISTANCE: Arterioles are the smallest arteries and they have a tunica media composed almost entirely of smooth muscles which responds to nerve and chemical stimulation. Constriction and dilatation of the arterioles are the main determinants of peripherals resistance. Vasoconstriction causes blood pressure to rise and vasodilatation causes it to fall. When elastic tissue in the tunica media is replaced by inelastic fibers as part of aging process, blood pressure rises. Dilatation and constriction of arterioles occurs selectively around the body, resulting in changes in the blood flow through organs according to their needs. The highest priorities are the blood supply to the brain and the heart muscle, and in an emergency, supply to the parts of the body are reduced in order to ensure an adequate supply to these organs. Generally, changes in the amount of blood flowing to any organ depend on how active it is. A very active organ needs more o2 and nutrients than resting organ and it produce more waste materials for excretion.

4 Greater the peripheral resistance is responsible for the diastolic pressure. Peripheral resistance depends upon the velocity and viscosity of blood and lumen of the arterioles. THE ELASTICITY OF THE ARTERY WALLS There is a considerable amount of elastic tissue in the arterial walls, especially in large arteries. Therefore, when the left ventricle ejects blood in to the already full aorta, it distends, and then the elastic recoil pushes the blood onwards. This distension and recoil occurs through the arterial system. During cardiac diastole the elastic recoil of the arteries maintain diastolic pressure. Systemic arterial blood pressure maintains the essential flow of substances into and out of the organs of the body. Control of BP especially to the vital organ is essential to maintain homeostasis. If the blood vessels were inelastic the systolic BP would have been very high and diastolic pressure would have been low. BP is determined by CO X PR. BLOOD VOLUME In increased blood volume will raise BP whereas diminished blood volume will decrease BP. VASOMOTOR CENTRE A collection of nerves and muscles cell bodies in the medulla of the brain that control the diameter of the blood vessels and BP. The vasomotor centre maintains the tone of blood vessels by constantly sending tonic impulses to the bld vessels through vasoconstrictor fiber. Destruction of vasomotor centre will cause dilatation of blood vessels and there will be fall of BP. MEASUREMENT OF BP The BP can be measured with the help of sphygmomanometer. METHODS OF MEASURING BP Auscultatory method; by notifying the variation of sound with stethoscope, the chest piece of stethoscope which is placed on the brachial artery little below the cuff. A series of sound is heard by the examining ears. Monitor where the first

5 sound started and stopped at the mercury reading first is systolic and down one is diastolic. Palpatory method: The first appearance of pulse at the wrist will give the systolic pressure. When the maximum pulse volume is obtained that will give diastolic pressure. Oscillatoy method: The first appearance of oscillation in the mercury column indicated the systolic pressure and the point of maximum oscillation the diastolic BP. TYPES OF EQUIPEMENT: 1. Mercury 2. Automated BP monitor PROCEDURE: a) Take stethoscope and sphygmomanometer b) Locate radial pulse c) Inflate cuff to about 30mmhg above the level at which radual pulse disappears d) Deflate the cuff slowly at approximately 2mmhg. e) Note level at which radial pulse returns. This is systolic pressure. f) Inflate the cuff to 30mmhg above the systolic pressure determined by palpation method. g) Auscultation with the steth must be lightly applied to the cubital fossa as excessive pressure can result h) Determine the BP by auscultation over the brachial artery at a point below the compression cuff using the bell of the steth.in falsely low BP.. i) Ascertain the SBP again as the cuff is deflated slowly at 2mmhg\sec j) Note the level when the sound finally disappears. This is diastolic pressure. GUIDELINES FOR ACCURATE BP READING: Accurate BP reading is dependent on technique, positioning and size of cuff. The arm should be in a resting position and at about heart level when the BP is measured.

6 Most BP cuffs have a mark that should be placed over the brachial artery, which is palpable just above the in front of the inner elbow. Use appropriate cuff A pediatric cuff is needed for a very thin arm while a very thick arm will require a thigh cuff. Blood pressure readings are also very dependent on movement or deflation, a minimum deflation is required for accurate reading. ABNORMALITIES: HYPERTENSION Hypertension is when BP rises and remains above the normal or persistently exceeding 140\90mmhg..Many people have high Blood pressure for years without knowing it and this is why high BP is often called `silent killer`. Uncontrolled BP can lead to stroke, congestive heart failure, heart attack or kidney failure. The kidneys control BP in several ways. If BP rises, kidneys increase their excretion of salt and water, which lowers blood volume and brings the BP back down to normal. Conversely, if BP falls, the kidneys decrease their excretion of salt and water, so the blood volume increases and BP returns to normalthe kidney also increase BP by secreting an enzyme calledrennin, which triggers angiotensin and aldosterone. Because the kidneys are important in controlling BP, many kidney diseases and abnormalities can cause high BP. Early in hypertension, the renal blood flow is reduced, while the gfr is maintained.the ensuring rise in filtration fraction promotes renal salt retention. Deterioration of renal function may decline the salt excretion which rises BP and promote further renal damage. CLASSIFYING BLOOD PRESSURE IN ADULTS CATEGORY SYSTOLIC DIASTOLIC Normal <130mmhg <85mmhg High Normal mmhg 85-90mmhg

7 Mild Hypertension mmhg 90-99mmhg Moderate Hypertension mmhg mmhg Severe Hypertension >180mmhg >110mmhg MEDICAL THERAPY 1. Diuretics Therapy 2.Betablockers 3. Calcium channel blockers 4.Alphablockers 5. ACE inhibitors 6. Central and peripheral acting agent 7.AR BLOCKERS NON MEDICAL THERAPY 1. Weight Reduction 2. Low salt and fat diet. 3. Minimal weight gain 4. Adequate dialysis HYPOTENSION Low BP can be defined as any BP that is below the normal expected for an individual in a given BP with symptoms.ex<90\60mmhg ORTHOSTATIC HYPOTENSION It is sudden fall in BP that occurs when a person assumes a standing position Causes Hypovolumia, bleeding, high UFR, Hypersensitivity reaction, diuretics, antidepressants and AHTN medications. NERVE MEDIATED HYPOTENSION NMHTN occurs when there is an abnormal interaction between the heart and brain both of which are structurally normal. CAUSES

8 Prolong standing, immediately after exercise, emotionally stressful events. TREATMENT Avoid sudden standing. Reset dry weight, Avoid AHTN medications and avoid stress. TEMPERATURE Body temperature is maintained by a thermostat located in the hypothalamus. Heat is gained through the process of metabolism and exercise and lost through radiation, convection, conduction, and evaporation. The temperature of the body remains fairly constant at 98.4*F (36.8*C) across a wide range of environmental temperature. In health variations are usually limited to between 0.5 and 0.75*c, although it is raised slightly in the evening, during exercise and women just after ovulation. When metabolic rate increases body temperature rises and when it decreases body temperature falls. To ensure this constant temperature balance is maintained between heat produced in the body and heat lost to the environment HEAT PRODUCTION Some of the energy released in the cells during metabolic activity is in the form of heat. Contraction of the skeletal muscles produces a large amount of heat and more strenuous the muscular exercise the greater the heat produced. Shivering involves muscles contraction and produces heat when there is the risk of body temperature falling below normal. The liver is chemically active, and heat produced as a by product. Metabolic rate and heat production are increased after eating. The digestive organs produce heat during peristalsis and by the chemical reaction involved in digestion. HEAT LOSS Most of the heat loss from the body occurs through skin. Small amounts are lost in expired air, urine and faeces. Only the heat lost through the skin can be regulated to maintained a constant body temperature.

9 MECHANISMS OF HEAT LOSS In evaporation, the body is cooled when heat is used to convert the water in seat to water vapour. In radiation, exposed parts of the body radiate heat away from the body. In conduction, clothes and other objects in contact with the skin take up heat. In convection, air passing over the exposed parts of the body is heated and rises, cool air replaces it and convection currents are set up. Heat is also lost from the clothes by convection. CONTROL OF BODY TEMPERATURE The temperature regulating centre in the hypothalamus is responsive to the temperature of circulating blood.this centre controls body temperature through autonomic nerve stimulation of the sweat glands when body temperature rises. The vasomotor centre in the medulla oblongata controls the diameter of the small arteries and arteriols, and there fore the amount of blood which circulates in the dermis. The vasomotor centre is influenced by the temperature of its blood supply and by nerve impulses from the hypothalamus. When body temperature raises the skin capillaries dialate and the extra blood near the surface increases heat loss by radiation, conduction and convection. The skin is warm and pink in colour. When body temperature falls arteriolar constriction conserves heat and the skin is whiter and feels cool. The amount of heat lost from the skin depends to a great extent on the amount of blood in the vessels in the dermis. FEVER This is often the result of infection and is caused by release of chemicals from damaged tissue and cells involved inflammation Pyrogens act on the hypothalamus, which releases prostaglandins that rest the hypothalamic thermostat to a higher temperature. The body responds by activating heat promoting mechanisms.ex shivering and vasoconstriction until new higher temperature is reached.

10 When the thermostat is reset to the normal level, heat loss mechanisms are activated. There is profuse sweating and vasodilatation accompanied by warm, pink skin until body temperature falls to the normal range again. HYPOTHERMIA Hypothermia is present when core temperature is below 95*F.At a rectal temperature below 32*c(89.6F) Compensatory mechanisms to restore body temperature usually fail, shivering is replaced by muscle rigidity and cramps, vasoconstriction fails to occur and there is lowered BP, pulse, and respiration rates. Mental confusion and disorientation occur. Death usually occur when the temperature falls below 25*C(77*F) MEASUREMENT OF TEMPERATURE Temperature can be measured by oral, tympanic, axillaries and rectal. Devices measure body temperature in Fahrenheit or Celsius. Conversion of Fahenheit to Celsius is *C=5/9(Degree F) - 32 *F= 9/5(Degree C) +32 Temperature variation will occur if patient has smoked, injected hot or cold liquids or food. Place the thermometer under the patient`s tongue in the right or left sublingual packet, which receives its blood supply from the carotid artery, which reflect inner core temperature. ABNORMALITIES Most of the renal failure patient have low temperature is due to accumulation of water and toxins. Fever is a sign of vascular access infection or systemic infection Fever during dialysis may be caused by poor cannulation techniques, or poor water or dialysate bath used to treat patients. PULSE NORMAL- (60 100/mt)

11 Palpation of arterial pulses provides valuable information about the cardiovascular system. T he pulse is guide to determine heart rate and rhythm. The heart rate is the number of times in a minute the pulsation is felt. The rhythm is the regularity of the pulsation that is the time between each beat. Pulses are palpated using the finger pads of the index finger and middle finger. Pulse can be taken various place.ex-wrist, brachial, radial, or carotid ABNORMALITIES: 1.Tachycardia 2.Bradycardia > 100 beat/ mt <60 beat/ mt RESPIRATORY RATE NORMAL BREATHS/ MT The respiratory rate is the number of times the patients completes one ventilatory cycle. Respiration rate vary with age, fever, anxiety, exercise and increase altitude. ABNORMALITIES: Bradypnea is a state of repiratory rate less than 12/mt Tachypnea is a state of respiratory rate greater than 20/mt Hyperventilation breathing is characterized by increased rate and depth of respiration.when hyperventilation occurs with ketoacidosis, it is very deep and laborious and is referred to as kusmal breathing. Biot breathing pattern is characterized by irregularly interspersed periods of apnea in disorganized irregular pattern ex-brain damage. Cheyne- stokes breathing is an abnormal pattern characterized by intervals of apnea interspersed with a deep and rapid breathing pattern. Ex- drug overdose, sever sickness, brain damage.

12 FLUID STATUS Our body fluid status to be maintained by normal kidneys When creatinine clearance is less than 10ml/mt volume overload occur Related to vascular volume overload, hypertension, pulmonary edema, crackles, increase jugular venous pressure, congestive heart failure and shortness of breath Related to extra vascular volume overload, pitting edema of feet and ankles, hands and fingers, sacral and ascities. INTERPRETATION OF FLUID STATUS An increase in heart rate >15 beats\mt, a fall in SBP OR DBP >15mmhg signifies the presence of postural hypotension, which may indicate intravascular volume depletion. Volume overload patient must also generate tachycardia, tachyp[nea, hypertension, highjvp, facial fluffiness or fatigue. WEIGHT Measuring weight is a good indicator of body fluid status in chronic renal failure. Pre dialysis weight helps to set appropriate ultra filtration and dry weight. Decreased dry weight may indicate volume depletion due to diarrhea, vomiting, and poor intake. Prolonged decrease weight lower than dry weight may indicate chronic illness, malnutrition, TB, Cancer etc. NURSING INTERVENTION Collaborate with Nephrologists and dietitian in planning fluid intake for each patient. Weight daily at same time and with same clothes for inpatients. Maintain intake and output chart. Assess status of edema, vital signs, auscultate lung field etc. Advice to reduce intradialytic weight gain.

13 Set proper dry weight. Report to nephrologists if any abnormal findings Reduce salt and water intake. Educate about renal failure and relationship to fluid balance, signs and symptoms of fluid over load. Take diuretics if ordered by nephrologists. Provide adequate ultra filtration Maintain hemoglobin, protein levels within the limit. Use small glass for drinking water. Avoid going out in sunny climate. INTERPRETATION OF FLUID STATUS Nursing Observation / Skill Pulse rate Respiration rate and nature Associated with advanced fluid imbalance Blood pressure Deficit (>100/minute) Weak and thready Easily obliterated Fluid Status Excess Plasma- to- interstitial fluid shift Bounding Not easily obliterated Interstitial-to-plasma fluid shift Shortness of breath Moist rates (crackle) Severe dyspnoea Interstitial to-plasma fluid shift Useful tool Postural hyotension (>10mmHg) Hypotension Contracted plasma Peripheral veins HNADS volume Hand veins take >3-5 seconds to fill in dependent position Hyper tension >140/90 mmhg Interstitial to-plasma fluid shift Hand veins take>3-5 seconds to empty when elevate Plasma-to-interstitial shift Interstitital fluid shift to-plasma

14 Peripheral veins Hand veins take>3-5seconds to fill in the dependent position. Neck Veins (1) Jugular veins O (external) N=2-3 cms Above sternal angle Not visible when client assessed at angle 45* Hand veins take 3-5seconds to empty when elevated. Veins engorged and clearly visible. Clearly visible at 45* client position.>2-3cms and up to the angle of the jaw. Central venous pressure Low CVP <4CM High C.V.P.12cm Facial appearance Pinched drawn facial expression, eyes appear sunken and soft to touch Eye lids puffy, cheeks appear fully than usual. Behavior changes Fatigue, thirst, giddiness Fatigue, restless, lassitude Fluid chart Negative balance Positive balance Skin turgor Poor skin turgor, pale and cool, dry mucous membranes dry axilla and groin reduced salivation Phonation Difficult in forming words Edema, pitting edema, brawny edema, limb edema, sacral edema Hoarseness -vocal cords REFERENCES 1.ESSENTIAL HUMAN ANATOMY AND PHYSIOLOGY 2.RENAL NURSING.