Surfactant is a phospholipid protein that reduces the surface tension
in the alveoli; without surfactant the alveoli would collapse.
Before X-ray nurse assess the client ability to inhale and hold his or
her breath.
Before taking radiograph nurse questions women regarding pregnancy or possibility
of pregnancy.
Early morning sputum sample is best for lab test.
Nurse instruct the client to rinse the mouth with water before sputum
sample collection.
Always collect the sputum sample before the client begins antibiotic
therapy.
Normally nurse obtain 15 ml of sputum for sample.
In Pulmonary angiography a catheter is inserted through the antecubital
or femoral vein into the pulmonary artery or of its branches.
Pulmonary angiography involves an injection of iodine or radiopaque
contrast material.
During pulmonary angiography client may feel an urge to cough,
flushing, nausea or a salty taste following injection of the dye.
Nurse assess for allergy to iodine, seafood or other radiopaque dyes in
client before pulmonary angiography.
Nurse avoid taking blood pressures for 24 hours in the extremity used
for injection during pulmonary angiography.
Thoracentesis is the removal of fluid or air from the pleural space via
a transthoracic aspiration.
In thoracentesis the client is positioned sitting upright, with the arms
and shoulders supported by a table at the bedside during procedure.
In thoracentesis if client cannot sit up, the client is placed lying in
bed toward the unaffected side, with the head of the bed elevated.
During thoracentesis nurse instruct the client not to cough, breathe
deeply or move during the procedure.
After thoracentesis nurse monitors client for pneumothorax, air
embolism and pulmonary edema.
Pulmonary function tests used to evaluate lung mechanics, gas exchange,
and acid-base disturbance through spirometric measurements, lung volume and
arterial blood gas levels.
Before pulmonary function test nurse consult with physician to holding
bronchodilators and analgesics that may depress the respiratory function.
Nurse remove the dentures of client before pulmonary function test.
Advised for avoid smoking and heavy meal before 4 to 6 hours.
For lung biopsy a transbronchial biopsy and a transbronchial needle
aspiration may be performed to obtain tissue for analysis.
An open lung biopsy is performed in the operating room.
In ventilation-perfusion lung scan a radionuclide may be injected for the
procedure.
The perfusion scan evaluates blood flow to the lungs.
The ventilation scan determines the patency of the pulmonary airways
and detects abnormalities in ventilation.
Before ventilation-perfusion lung scan nurse assess the client for
allergies to dye, iodine or seafood. Remove jewelry around the chest area.
Skin test uses for helps to diagnose various infectious diseases.
Usually in skin test gives injection at the upper third of the inner
surface of the left arm.
After injection nurse mark the injection test site and documents the
date, time and test site.
Nurse advised the client not to scratch the test site to prevent
infection and possible abscess formation.
Client avoid the skin test site from washing.
Nurse interpret the reaction at the injection site 24 to 72 hours after
administration of the test antigen.
Arterial blood gas analysis measures the dissolved oxygen and carbon
dioxide in the arterial blood helps indicate the acid-base state.
Nurse perform Allen’s test before drawing radial artery specimens.
Provide 30 minutes rest before arterial blood specimens collection to
ensure accurate measurement of body oxygenation.
Nurse avoid suctioning in the client before drawing an ABG sample
because it depletes client’s oxygen.
Nurse place the specimen on ice and transport the ABG sample to the laboratory
within 15 minutes.
Nurse apply pressure on puncture site 5 to 10 minutes or longer if client
receiving anticoagulant therapy or has bleeding disorder.
Normal Arterial blood gas values: (a) pH: 7.35 to 7.45 (b) Pco2: 35 to 45 mmHg (c) HCO3: 22 to 27 mEq/L (d) Po2: 80 to 100 mmHg (e) O2 saturation: 96% to 100%
Oxyhemoglobin dissociation curve: No shift
Nurse note the client temperature; oxygen and types of ventilation that
receiving by client on the laboratory form for ABG analysis.
The pulse oximetry records the capillary oxygen saturation in percentage.
Register the oxygen saturation of the client hemoglobin.
The normal value of pulse oximetry is 96% to 100%.
A pulse oximeter reading can alert the nurse to hypoxemia before
clinical signs occur.
A pulse oximetry reading lower than 91% necessitate physician
notification; if the reading is lower than 85% oxygenation of body tissues is
compromised and a reading lower than 70% is life threatening.
The main types of exercises include in breathing retraining is pursed-lip
breathing and diaphragmatic breathing.
The client should exhale three times longer than inhalation by blowing
through pursed lips.
Chest physiotherapy (CPT) is percussion, vibration and postural drainage
techniques are preformed over the thorax to loosen secretions in the affected
area of the lungs and move them into more central airways.
Chest physiotherapy is contraindicated in unstable vital signs,
increased ICP, bronchospasm, history of pathological fractures, rib fracture
and chest incision client.
Percussion and vibration techniques, the nurse perform when the client
exhales cough.
Perform chest physiotherapy in the morning on arising, 1 hour before
meals or 2 to 3 hours after meals.
Nurse Stop chest physiotherapy if pain occurs.
If the client is receiving a tube feeding nurse stop the feeding and
aspirate the residual before beginning chest physiotherapy.
During chest physiotherapy bronchodilators prescribed, it administer 15
minutes before the procedure.
Nurse place a layer of material (gown or pajamas) between the hands or
percussion device and the client skin during chest physiotherapy.
Nurse percuss the area for 1 to 2 minutes in chest physiotherapy.
Nurse stop the chest physiotherapy if cyanosis or exhaustion occurs.
Client assume a sitting or upright position during incentive spirometry.
During incentive spirometry client place the mouth tightly around the mouthpiece
of the device, inhale slowly, hold the breath for 5 seconds and then exhale through
pursed lips. Client repeat this procedure 10 times.
In spirometry during inhalation client maintains indicator between 600
and 900 Marks.
A nasal cannula (nasal prongs) is used at a flow rate of 1 to 6 L/min,
providing approximate oxygen concentration of 24% (at 1 L/min) to 44% (at 6
L/min).
Flow rates higher than 6 L/min in nasal cannula do not significantly
increase oxygenation because the anatomical reserve or dead space (oral and
nasal cavities) is full.
A nasal cannula is used for the client with chronic airflow limitation
and for long-term oxygen use.
Nasal cannula oxygen therapy contraindicated in client with nasal
obstruction like nasal polyps.
A client who is hypoxemic and has chronic hypercapnia requires low
levels of oxygen delivery at 1 to 2 L/min because a low arterial oxygen level
is the client’s primary drive for breathing.
Nurse add humidification as prescribed when a flow rate higher than 2 L/min
is prescribed in nasal cannula.
A simple face mask is used to deliver oxygen concentrations of 40% to
60% for short-term oxygen therapy or to deliver oxygen in an emergency.
In simple face mask a minimal flow rate of 5 L/min is needed to prevent
the rebreathing of exhale air. (To flush the mask of carbon dioxide)
Nurse be sure that the mask fits securely over the nose and mouth
because a poorly fitting mask reduces the fraction of inspired oxygen (Fio2)
delivered.
Partial rebreather mask consists of a mask with a reservoir bag that
provides an oxygen concentration of 70% to 90% with flow rates of 6 to 15
L/min.
In partial rebreather mask nurse maintain a flow rate enough to bag
two-thirds full during inspiration in needed.
In partial rebreathers mask the client rebreathes one-third of the
exhaled tidal volume, which is high in oxygen thus providing a high fraction of
inspired oxygen.
Deflation of reservoir results in decrease oxygen delivery and
rebreathing of exhaled air.
A nonrebreather mask provides the highest concentration of oxygen and
can deliver a fraction of inspired oxygen higher than 90% depending on the
client's ventilatory pattern.
In nonrebreather mask suffocation can occur if the reservoir bag kinks
or if the oxygen source disconnected.
Face tent oxygen therapy useful in the client who has facial trauma or
burn.
Aerosol mask used for the client who requires high humidity after
extubation or upper airways surgery or for the client who has thick secretions.
Tracheostomy collar and T-piece can be used to deliver high humidity
and desired oxygen to the client with tracheostomy and laryngectomy or
endotracheal tube.
Venturi mask is high flow oxygen delivery system. The venturi mask is based
on the mechanism that pulls in a specific proportional amount of room air for
each liter of oxygen delivered.
In venturi mask 24% to 55% fraction of inspired oxygen with flow rates
of 4 to 10 L/min.
Nurse keep the air entrapment port of venturi mask open and uncovered to
ensure adequate oxygen delivery.
Poorly
fit mask and kinks of tubing altered the fraction of inspired oxygen.
Types of Mechanical ventilation: (a) Pressure cycled ventilation (b) Time cycled ventilation (c) Volume cycled ventilation (d) Microprocessor
ventilation
Pressure cycled ventilator pushes air into the lungs until a specific
airway pressure is reached. It is used for short periods, as in the
postanesthesia care unit.
Time cycled ventilator pushes air into the lungs until a pre-set time
has elapsed. It is used for the pediatric or neonatal client.
Volume cycled ventilator pushes air into the lungs until a pre-set
volume is delivered. A constant tidal volume is delivered regardless of the changing
compliance of the lungs and chest wall or the airway resistance in the client
or ventilator.
In Microprocessor ventilator a computer or microprocessor is built into
the ventilator to allow continuous monitoring of ventilatory functions, alarms,
and client parameters. This type of ventilator is more responsive to clients
who have severe lung disease or require prolonged weaning.
Controlled mode of ventilator: (1) The client receives a set tidal volume at a
set rate. (2) Used for clients who cannot initiate
respiratory efforts. (3) It is least used mode, if the client
attempts to initiate a breath, the ventilator blocks the effort.
Assist-control mode ventilator: (1) Most commonly used mode. (2) Tidal volume and ventilatory rate are pre-set
on the ventilator. (3) The ventilator takes over the work of
breathing for the client. (4) The ventilator is programmed to respond to
the client's inspiratory effort if the client does initiate a breath. (5) The ventilator delivers the pre-set tidal
volume when the client initiates a breath while allowing the client to control
the rate of breathing. (6) If the client's spontaneous ventilatory
rate increases, the ventilator continuous to deliver a pre-set tidal volume
with each breath, which may cause hyperventilation and respiratory alkalosis.
Synchronised intermittent mandatory ventilation (SIMV): (1) It is similar to assist-control ventilation
in that the tidal volume and ventilatory rate are pre-set on the ventilator. (2) Allows the client to breath spontaneously
at her or his own rate and tidal volume between the ventilator breaths. (3) Can be used as a primary ventilatory mode
or as a weaning mode. (4) When
SIMV is used as a weaning mode, the number of SIMV breaths is decreased
gradually and the client gradually resumes spontaneous breathing.
A client receiving mechanical ventilation, nurse always assess the
client first and then assess the ventilator.
In ventilator client nurse monitors client skin color, particularly in
the lips and nail beds.
In ventilator client nurse assess the need for suctioning and observe
the type, color, and amount of secretions.
If the cause for an alarm cannot be determined in ventilatory client;
the nurse ventilate the client manually with a resuscitation bag until the
problem is corrected.
Nurse empty the ventilator tubing when moisture collects.
In ventilator client nurse keeps ready resuscitation equipment at
bedside.
Nurse never set ventilator alarm controls to the off position.
Hypotension, pneumothorax, subcutaneous emphysema, GI alteration such
as stress ulcer, malnutrition if nutrition not maintain, infection, muscular
deconditioning, ventilator dependence or inability to wean are the complications
of ventilator.
Weaning is process of going from ventilator dependence to spontaneous
breathing.
Pain at the injury site that increase with inspiration, tenderness at
the site, shallow respiration and client splints the chest or fracture noted on
chest X ray are signs of rib fracture.
Client with rib fracture, flail chest, pulmonary contusion, and pneumothorax are placed in Fowler’s position.
Paradoxical respiration is seen in flail chest.
In paradoxical respiration the inward movement of a segment of the
thorax during inspiration with outward movement during expiration.
Client with flail chest and pulmonary contusion nurse prepare for
mechanical ventilation with PEEP if required.
The diagnosis of pneumothorax is made by chest X-ray.
In pneumothorax breath sound is absent on affected side.
In open chest wound chest pneumothorax, a sucking sound is heard during
respiration.
Client with pneumothorax, chest tube placement is performed and remain
it in place until the lung has expanded fully.
Acute respiratory failure occurs when insufficient oxygen is transported
to the blood or inadequate carbon dioxide is removed from the lungs and the
client’s compensatory mechanism fail.
In acute respiratory failure the Pao2 lower than 60 mm Hg,
arterial oxygen saturation (Sao2) lower than 90%, or partial
pressure arterial carbon dioxide (Paco2) greater than 50 mm Hg
occurring with acidaemia.
Asthma
is marked by airway inflammation and hyperresponsiveness to a variety of
stimuli or triggers.
Nurse position the client in a high Fowler’s position or sitting to aid
in breathing during asthma attack. Administer oxygen and bronchodilators.
Record the color, amount and consistency of sputum. Administer corticosteroids
as prescribed. Auscultate lung sound before, during and after treatment.
COPD also known as chronic obstructive lung disease and chronic airflow
limitation.
COPD is a disease state characterized by airflow obstruction caused by
emphysema or bronchitis. It is not completely reversible.
COPD leads to pulmonary insufficiency, pulmonary hypertension and
corpulmonale.
Corpulmonale is enlargement of the right ventricle of the heart as a
response to increase resistance or high BP in the lung.
Barrel chest (emphysema), use of accessory muscles for breathing,
prolonged expiration, orthopnea, congestion and hyperinflation seen on chest
X-ray, ABG levels that indicate respiratory acidosis and hypoxemia, or
pulmonary function tests demonstrate decreased vital capacity, cough,
exertional dyspnea, wheezing and crackles, sputum production, weight loss are the signs of COPD.
In COPD client nurse administer a low concentration of oxygen 1 to 2
L/min to stimulate breath is a low arterial Po2 instead of an
increased Pco2.
Client with COPD nurse advice for diaphragmatic or abdominal breathing
techniques and pursed-lip breathing techniques.
Place the client with COPD in Fowler’s position and leaning forward (orthopnea
position) to aid in breathing.
SARS is respiratory illness caused by coronavirus.
Pneumonia is infection of the pulmonary tissue, including the
interstitial spaces, the alveoli and the bronchioles.
Sputum culture in pneumonia identified the organisms of pneumonia. The
WBC count and erythrocyte sedimentation rate are elevated.
Client with COPD and pneumonia encourage to take fluid up to 3 L/day to
thin secretions.
In pneumonia provide high calorie, high protein diet with small
frequent meals.
Influenza also known as the flu; highly contagious acute viral
respiratory infection.
Influenza may be caused by several viruses, usually known as type A, B,
and C.
Yearly vaccination prevents from influenza especially older than 50,
individual with chronic illness, immunocompromised client and health person who
providing direct care.
Influenza vaccine contraindicated in the individual with egg allergies.
Avian influenza A affects the bird's caused by H5N1 virus.
Swine influenza is caused by H1N1 virus.
Legionnaire's disease is acute bacterial infection caused by Legionella
pneumophilia.
Legionella is transmitted by infected cooling tower water and warm
stagnant water supplies.
In pleural effusion the pleuritic pain that is sharp and increase with
breathing and decrease breath sound over the affect area.
If pleural Effusion is recurrent the client is prepared for pleurectomy
or pleurodesis as prescribed.
Empyema is collection of pus within the pleural cavity.
In empyema the fluid is thick, opaque and foul-smelling.
The most common cause is pulmonary infection in empyema.
Pleurisy is the inflammation of the visceral and parietal membranes may
be caused by pulmonary infraction or pneumonia.
In pleurisy the visceral and parietal membranes rub together during
respiration and cause pain.
Pleurisy usually occurs on one side of the chest, usually in the lower
lateral portions in the chest wall.
In pleurisy knife-like pain aggravated on deep breathing and coughing.
Pulmonary embolism occurs when a thrombus forms (Most commonly in a
deep vein), detached, travels to the right side of the heart, and then lodges
in a branch of the pulmonary artery.
Signs and symptoms of a pulmonary embolism include the sudden onset of
dyspnea, apprehension, and restlessness, a feeling of impending doom, cough,
hemoptysis, tachypnea, crackles, petechiae over the chest and axillae, and a
decreased arterial oxygen saturation.
Histoplasmosis is a pulmonary fungal infection caused by spores of
histoplasma capsulatum.
The transmission of histoplasma occurs by the inhalation of spores
which commonly found in contaminated soil or bird droppings.
Sarcoidosis is the presence of epithelioid cell tubercles in the lung.
The cause is unknown, but a high titer of Epstein-Barr virus may be noted.
Kveim test is performed to find out sarcoidosis. Sarcoid node antigen
is injected intradermally and causes a local nodular lesion in about 1 months.
Pneumoconiosis is lung disease caused by dust. Silicosis or coal
miner's disease (black lung).
Mycobacterium tuberculosis is a nonmotile, nonsporulating, acid-fast
rod that secrets niacin, when the bacillus reaches a susceptible site, it multiplies
freely.
M tuberculosis is an aerobic bacterium it primarily affects the
pulmonary system, especially the upper lobes.
M tuberculosis also affects the brain, intestines, peritoneum, kidney,
joints and liver.
Tuberculosis has an invidious onset and many clients are not aware of
symptoms until the disease is well advanced.
Improper or noncompliant use of treatment programmes may cause the development
of mutations in the tubercle bacilli, resulting in a multidrug resistant strain
of tuberculosis (MDR-TB).
An individual who has received a Bacille Calmatte-Guerin vaccine will
have a positive tuberculin skin test result and should be evaluated for
tuberculosis with a chest X-ray.
Tuberculosis is diagnosed by chest X-ray, Quanti FERON-TB Gold test,
sputum culture and Mantoux skin test.
A sputum culture identifying M. Tuberculosis conforms the diagnosis.
A positive Mantoux reaction does not mean that active disease is present
but indicates previous exposure to tuberculosis or the presence of inactive
(dormant) disease.
In Mantoux test purified protein derivative containing 5 tuberculin
units is administered intradermally in the forearm.
An area of induration measuring 10 mm or more in diameter 48 to 72
hours after injection indicates that the individual has been exposed to tuberculosis.
For individual with HIV infection or who are immunosuppressive a
reaction of 5 mm or more is considered positive.
The client with active tuberculosis is placed in respiratory isolation
precautions in a negative-pressure room; to maintain negative pressure, the
door of the room must be tightly closed. The room should have at least six
exchanges of fresh air per hour and should be ventilated to the outside
environment, if possible.
When the results of three sputum cultures are negative, the client is
no longer considered infectious and usually can return to former employment.
The metered-dose inhalers should not be put in the mouth but held about
two finger widths (1.5 inches) in front of mouth.
If two different inhaled medications are prescribed, instruct the
client to wait 5 minutes following administration of the first before inhaling
the second.
In two different inhaled medications are prescribed and one of them
glucocorticoid; nurse administer the bronchodilator first and the corticosteroid
second.
Bronchodilators should be used with caution in client with hypertension,
diabetes mellitus and narrow-angle glaucoma.
Sympathomimetic bronchodilators relax the smooth muscle of the bronchi
and dilate the air way.
A spacer is a device that enhance the delivery of medication.
Intravenous theophylline preparations should be administered slowly and
always via an infusion pump.
The early signs of theophylline toxicity include restlessness, nervousness,
tremors, palpitations and tachycardia.
Anticholinergics blocking the muscarinic receptors in the bronchi, which
results in bronchodilation.
Side effects of anticholinergics is dry mouth and irritation of the pharynx;
sucking of sugarless candy will help to relieve symptoms.
The client with a peanut allergy should not take ipratropium anticholinergics
because the product contains soy lecithin, which is in the same plant family as
peanut.
Leukotriene modifiers used in the prophylaxis and treatment of chronic
bronchial asthma. (not used for acute asthma episodes).
Monoclonal antibody omalizumab is a recombinant DNA-derived humanized
immunoglobulin-G (IgG) murine that selectively binds to IgE to limit the
release of mediators in the allergic response.
Antihistamines are called histamine antagonists or H1 blockers;
these medications compete with histamine for receptor sites thus presenting a
histamine response.
Nasal decongestant shrinks nasal mucosal membranes and reduce fluid
secretions.
Nasal decongestant can cause tolerance and rebound nasal congestion
(vasodilation) caused by irritation of the nasal mucosal. Therefore, the client
needs to be informed that these medications should not be used for longer than
48 hours.
Expectorants loosen bronchial secretions so that they can be eliminated
with coughing; they are used for a dry unproductive cough and to stimulate
bronchial secretions.
Mucolytic agents’ thin mucous secretions to make the cough more
productive.
Acetylcysteine is mucolytic that administered by nebulization, should
not be mixed with another medication.
Antitussives act on the cough control centre in the medulla to suppress
the cough reflex; used for a cough that is non-productive and irritating.
An opioid antagonist reverses respiratory depression in opioid
overdose.
Alvimopan, Methylnaltrexone, Nalmefene, Naloxone, Naltrexone are opioid
antagonists.
Individual with active tuberculosis are treated for 6 to 9 months;
however, client with HIV infection are treated for a longer period of time.
Most client with tuberculosis has negative sputum cultures after 3
months of compliance with medication therapy.
Individual who have been exposed to active tuberculosis are treated
with preventive isoniazid for 9 to 12 months.
Isoniazid, Rifampin, Rifabutin, Rifapentine, Ethambutol and
Pyrazinamide are first line anti-tuberculosis medications.
Isoniazid is bactericidal and inhibits the synthesis of mycolic acids.
Isoniazid is contraindicated in closed with hypersensitivity or with
acute liver disease.
Side effects of isoniazid are hypersensitivity, peripheral neuritis,
neurotoxicity, hepatotoxicity, and pyridoxine (vit-B6) deficiency,
nausea and vomiting, dry mouth, dizziness, hyperglycemia and vision changes.
Administer isoniazid 1 hour before or 2 hours after a meal because food
may delay absorption.
Administer pyridoxine as prescribed to reduce the risk of neurotoxicity.
Rifampin inhibits bacterial RNA synthesis. It binds to DNA-dependent
RNA polymerase and blocks RNA transcription.
Rifampin cause red-orange colored body secretions.
Ethambutol is bacteriostatic and slow-acting. It inhibits bacterial RNA
synthesis and is active only during cell division or use with other
bactericidal drugs.
Ethambutol is contraindicated in clients with hypersensitivity or optic
neuritis and in children younger than 13 years.
Ethambutol cause optic neuritis and peripheral neuritis.
Nurse obtain baseline visual acuity and color discrimination
especially to green before given Ethambutol.
The exact mechanism of action of Pyrazinamide is unknown. Pyrazinamide
may be bacteriostatic or bactericidal, depending on its concentration at the
infection site and susceptibility of infecting organism.
Increase liver function tests and uric acid levels, arthralgia, myalgia,
photosensitivity, hepatotoxicity and thrombocytopenia are side effects of
Pyrazinamide.
Pyrazinamide take with food and avoid sunlight to prevent from photosensitivity.
Rifabutin inhibits mycobacterial DNA-dependent RNA polymerase and suppresses
protein synthesis.
Rifabutin used to prevent disseminated Mycobacterium avium complex
(MAC) disease in client with HIV infection.
Rifabutin used to treat active MAC disease and tuberculosis in client
with HIV infection.
Rifabutin affects oral contraceptives action so a nonhormonal method of
birth control advice to client.
Rifabutin, Rifampin and Rifapentine cause red-orange color body
secretions.
Rifapentine used only for pulmonary tuberculosis.
Rifapentine affect blood levels of oral contraception and warfarin.
Rifabutin and Rifapentine can be taken without regard to food.
Capreomycin sulfate do not administer to client's receiving streptomycin.
Aminosalicylic acid inhibits folic acid metabolism in mycobacteria.
Amantadine, Oseltamivir, Rimantadine, and Zanamivir are antiviral influenza
medications.
Afterload is the force against which the heart has to pump to eject blood
from the left ventricle.
Baroreceptors (pressure receptors) are specialized nerve endings
located in the walls of the aortic arch and carotid sinuses. They are affected
by changes in the arterial blood pressure.
Capillary pressure or hydrostatic pressure is the pressure exerted by
the blood against the capillary wall. Normal capillary pressure is 25 to 30 mm
Hg at the arterial end of the capillaries and 10 to 15 mm Hg at the venous end.
Chemoreceptors is nerve endings located in the aortic arch and carotid
bodies that are stimulated by hypoxemia and that subsequently transmit impulses
to the central nervous system.
Excitability is the ability of cardiac muscle cells to depolarize in
response to a stimulus.
Mean arterial pressure (MAP) is an approximation of the average
pressure in the systemic circulation throughout the cardiac cycle; used in
hemodynamic monitoring. Mean arterial pressure must be at least 60 mm Hg for
adequate organ perfusion.
Paradoxical blood pressure is an exaggerated decrease in systolic
pressure by more than 10 mm Hg during the inspiratory phage of the respiratory
cycle. Normal value is 3 to 10 mm Hg.
Preload is the volume of blood stretching the left ventricle at the end
of diastole.
Postural hypotension (orthostatic) is a blood pressure decrease of more
than 10 to 15 mm Hg of the systolic pressure or a decrease of more than 10 mm
Hg of the diastolic pressure and a 10% to 20% increase in heart rate.
Postural hypotension occurs when the clients blood pressure is not
maintained adequately when moving from a lying to a sitting or standing
position.
Pulmonary capillary wedge pressure (PCWP) is the measurement obtained
during momentary balloon inflation of a pulmonary artery catheter; it is
reflective of the left ventricular end-diastolic pressure. The PCWP normally
ranges between 6 to 12 mm Hg.
Decrease PCWP indicates hypovolemia, whereas increased PCWP indicates
hypervolemia, left ventricle failure and mitral regurgitation.
Normal pulse pressure is 30 to 40 mm Hg.
Refractoriness is a property of excitable tissue. Refractoriness prevents
uncontrolled rapid cardiac contractions and helps preserve the heart rhythm.
Stretch receptors are nerve endings located in the vena cava and the
right atrium that respond to pressure changes affecting circulatory blood volume.
Stroke volume is the amount of blood ejected from the left ventricle
with each contraction. The normal stroke volume is 70 to 130 mL/heartbeat.
The stroke volume can be affected by preload, afterload, contractility
and the frank-Starling law.
Venous pressure is the force exerted by the blood against the vein
walls. Normal venous pressure is highest in the extremities (5 to 14 cm H2O
in the arm) and the lowest closest to the heart (6 to 8 cm H2O in
the inferior vena cava).
The pericardial space is between the parietal and visceral layers of
heart; it holds 5 to 20 mL of pericardial fluid, lubricates the pericardial surfaces,
and cushions the heart.
SA node generates electrical impulses at 60 to 100 times per minutes.
AV node initiate and sustain a heart rate 40 to 60 beats/min.
Purkinje fibres are a diffuse network of conducting strands, located
beneath the ventricular endocardium.
Purkinje fibres can act as the pacemakers with a rate between 20 to 40
beats per minute.
Coronary artery is divided into two branch right coronary artery and
left coronary artery.
The left coronary artery consists of two major branches, left anterior
descending and the circumflex arteries.
There are four heart sounds, S1, S2, S3 and S4.
The first heart sound (S1) is heard as the atrio-ventricular valves
close and is heard loudest at the apex of the heart.
The second heart sound (S2) is heard when the semilunar valves close and
is heard loudest at the base of the heart.
A third heart sound (S3) may be heard if ventricular wall compliance is
deceased and structures in the ventricular wall vibrate; this can occur in conditions
such as congestive heart failure or ventricular regurgitation. However, a third
heart sound may be normal in individuals younger than 30 years.
A fourth heart sound (S4) may be heard on atrial systole if resistance
to ventricular filling is present; this is an abnormal finding and the causes
include cardiac hypertrophy, disease or injury to the ventricular wall.
The normal sinus heart rate is 60 to 100 beats per minute.
Sinus tachycardia is a rate more than 100 beats per minute.
Sinus bradycardia is a rate less than 60 beats per minute.
Stimulation of sympathetic nerve fibres releases the neurotransmitter
norepinephrine, producing an increased heart rate, increased conduction speed
through the AV node, increased atrial and ventricular contractility and
peripheral vasoconstriction.
Stimulation of parasympathetic nerves fibres release the
neurotransmitter acetylcholine which decrease the heart rate and lessens atrial
and ventricular contractility and conductivity.
Renin a potent vasoconstrictor, causes the BP to increase.
CK-MB, (creatine kinase myocardial muscle), lactate dehydrogenase
(LDH), troponin and myoglobin are cardiac enzymes that elevated in heart muscle
damage.
CK-MB elevation occurs within hours and peaks at 18 hours following an
acute ischemic attack.
Elevations in LDH levels occur 24 hours following myocardial infraction
and peak in 48 to 72 hours.
Troponin is composed of three proteins; troponin C, cardiac troponin I,
and cardiac troponin T.
Troponin I especially have a high affinity for myocardial injury; it
rises within 3 hours and persists for up to 7 to 10 days.
The myoglobin level rises within 2 hours after cell death, with a rapid
decline in the level after 7 hours.
The lipid profile measures serum cholesterol, triglycerides and lipoprotein
levels.
The lipid profile is used to assess the risk of developing coronary
artery disease.
The desirable range for serum cholesterol is lower than 200 mg/ dL,
with low-density lipoprotein cholesterol lower than 130 mg/dL and high-density
lipoprotein cholesterol at 30 to 70 mg/dL.
Homocysteine elevated levels may increase the risk of cardiovascular
disease, level should be less than 14 mmol/dL.
Highly sensitive C-reactive protein (hsCRP) level over 3 mg/dL places
the client at high risk for heart disease. (Normal less than 1 mg/dL).
Hypokalemia increase the risk of digoxin toxicity.
Hypokalemia shows flattening and inversion of the T wave, the
appearance of a U wave and ST depression.
Hyperkalemia shows tall peaked T waves, widened QRS complexes, prolonged
PR intervals or flat P waves.
Hypocalcemia cause prolonged ST and QT intervals.
Hypercalcemia can cause a shortened ST segment and widened T wave.
A low magnesium level can cause ventricular tachycardia and fibrillation.
Hypomagnesemia cause tall T wave and depressed ST segments.
Hypermagnesemia include a prolonged PR interval and widened QRS
complex.
B type natriuretic peptide (BNP) is released in response to atrial and
ventricular stretch, it serves as a marker for congestive heart failure (CHF).
The BNP levels should be lower than 100 pg/mL; the higher the level, the
more severe the CHF.
Holter monitor is non-invasive test that identifies dysrhythmias.
Electrocardiography is non-invasive diagnostic test records the
electrical activities of the heart.
Echocardiography is non-invasive procedure based on the principles of
ultrasound and evaluates structural and functional changes in the heart.
ECG reflects the electrical activity of cardiac cells and records
electrical activity at a speed of 25 mm/sec.
An electrocardiographic strip consists of horizontal lines representing
seconds and vertical lines representing voltage.
Each small square represents 0.04 second.
Each large square represents 0.20 second.
The U wave may follow the T wave.
A prominent U wave may indicate an electrolyte abnormality such as
hypokalemia.
Exercise electrocardiography testing (Stress test) is non-invasive test
studies the heart during activity and detects and evaluates coronary artery
disease.
Treadmill testing is the most commonly used mode of stress testing.
Digital subtraction angiography is testing combines X-ray techniques
and a computerized subtraction technique with fluoroscopy for visualization of
the cardiovascular system.
In myocardial nuclear perfusion imaging (MNPI) most commonly include
Technetium pyrophosphate scanning, thallium imaging and multigated cardiac
blood pool imaging; all these evaluate the cardiac motion and calculate the
ejection fraction.
Client with pacemaker or other implanted items is contraindicated for
MRI.
Electronic-beam computer tomography scan (EBCT) determines whether calcification
is present in the arteries; coronary artery calcium (CAC) score is provided by
this test. (A score higher than 400 requires intensive preventive treatment)
In Right-sided heart catheterization. The catheter is inserted into the
femoral vein and advanced into the inferior vena cava (or, if into an antecubital
or basilic vein, through the superior vena cava), right atrium, and right
ventricle, and into the pulmonary artery.
The client height and weight data are needed during cardiac catheterization
to calculate the amount of dye is injected.
Nurse assess the client for allergies to seafood, iodine or radiopaque
dyes before cardiac catheterization.
Nurse apply pressure dressing to insertion site of cardiac catheterization
and monitor the site for bleeding and hematoma formation.
Nurse keeps the client leg straight or extended for 4 to 6 hours as
prescribed after cardiac catheterization.
After cardiac catheterization maintain strict bed rest for 6 to 12
hours and do not elevate the head of the bed more than 15 degree.
If the antecubital vessel was used in cardiac catheterization; the arm
is immobilized with arm board.
Percutaneous transluminal coronary angioplasty (PTCA) is an invasive,
nonsurgical technique in which one or more arteries are dilated with a balloon
catheter to open the vessel lumen and improve arterial blood flow.
Arterial dissection or rupture, embolization of plaque fragments,
spasm, and acute MI are complications of PTCA.
Nurse stop metformin before 48 hours in cardiac catheterization client
who needs iodine dye administration during procedure because of the risk of lactic
acidosis.
Nurse monitor the vital signs, assess distal pulses in both
extremities, maintain bed rest, and keep the limbs straight for 6 to 8 hours or
administer anticoagulant as prescribed after PTCA.
Atherectomy
removes plaque from a coronary artery by the use of a cutting chamber on the
inserted catheter or a rotating blade that pulverized the plaque.
Transmyocardial revascularization uses a high-powered laser that
creates 20 to 24 channels through the ventricular muscle of the left ventricle;
blood enters these small channels, providing the affected region of the heart
with oxygenated blood.
Following arterial revascularization, monitor for a sharp increase in
pain because pain is frequently the first indicator of postoperative graft
occlusion.
The saphenous vein, internal mammary artery, or other arteries may be
used to bypass lesions in the coronary arteries.
A donor heart from an individual with a comparable body weight and ABO
compatibility is transplanted into a recipient within less than 6 hours of
procurement.
After heart transplant the client requires lifetime immunosuppressive
therapy.
In sinus bradycardia the atrial and ventricular rhythms are regular but
atrial and ventricular rates are less than 60 beats/min.
In sinus tachycardia the atrial and ventricular rates are 100 to 180
beats per minute. Atrial and ventricular rhythms are regular.
In Atrial fibrillation multiple rapid impulses from many foci depolarize
in the atria in a totally disorganised manner at a rate of 350 to 600 times per
minute.
In atrial fibrillation no definitive P wave can be observed, only
fibrillatory waves seen before each QRS complex.
In atrial fibrillation nurse prepare the client for cardioversion as
prescribed.
Premature ventricular contractions (PVCs): It is early ventricle
contractions result from increased irritability of the ventricle. PVCs
frequently occur in repetitive patterns such as bigeminy, trigeminy, and quadrigeminy.
In PVCs the QRS complexes may be unifocal or multifocal.
Bigeminy: Premature ventricular contraction every other heartbeat.
Trigeminy: PVC every third heartbeat.
Quadrigeminy: PVC every fourth heartbeat.
Couplet or pair PVCs: Two sequential PVCs.
Unifocal PVCs: Uniform upward or downward deflection, arising from the
same ectopic focus.
Multifocal PVCs: Different shapes, with the impulse generation from the
different sites.
R-on-T phenomenon: PVC falls on the T wave of the preceding beat; may
precipitate ventricular fibrillation.
Nurse evaluate electrolytes, particularly the potassium level in client
with premature ventricular contractions, because hypokalemia can cause
premature ventricular contractions.
Lidocaine (Xylocaine) may be prescribed in premature ventricular
contractions.
Ventricular tachycardia occurs due to repetitive firing of an irritable
ventricular ectopic focus at a rate of 140 to 250 beats/min or more.
Pulseless client with ventricular tachycardia is manage by defibrillation
and CPR.
Ventricular fibrillation is impulses from many irritable foci in the
ventricles, fire in a totally disorganised manner.
Ventricular fibrillation is fatal if not successfully terminated within
3 to 5 minutes. Client lacks a pulse, BP, respiration, and heart sounds.
Client with ventricular fibrillation manage immediately by defibrillation,
up to 3 times consecutively at 200, 300, and 360 joules shock.
Vagal manoeuvres, Valsalva maneuver, cardioversion, defibrillation and
pacemakers are the treatment measures used to treat dysrhythmias.
Vagal manoeuvres induce vagal stimulation of the cardiac conduction
system and are used to terminate supraventricular tachydysrhythmias.
In Valsalva maneuver the physician instructs the client to bear down or
induces a gag reflex by the client to stimulate a vagal response.
Cardioversion is synchronized countershock to convert an undesirable
rhythm to a stable rhythm.
Cardioversion can be an elective procedure performed by the physician
for stable tachydysrhythmias resistant to medical therapies or an emergent
procedure for hemodynamically unstable ventricular or supraventricular
tachydysrhythmias.
In cardioversion the lower amount of energy is used than with defibrillation.
The defibrillator is synchronized to the client's R wave to avoid
discharging the shock during the vulnerable period (T wave).
If the defibrillator were not synchronized, it could discharge on the T
wave and cause ventricular failure.
Nurse stop the oxygen during the defibrillation procedure to avoid the hazards of
fire.
During defibrillation nurse ensure that no one is touching the bed or
the client when delivering the countershock.
Defibrillation is an asynchronous countershock used to terminate
pulseless ventricular tachycardia or ventricular failure.
In defibrillation the three rapid consecutive shocks are delivered with
the first at an energy of 200 J. If unsuccessful the shock is repeated at 200
to 300 J. The third and subsequent shocks will be 360 J.
In defibrillation the one paddle is placed at the third intercostal
space to the right of the sternum; the other is placed at the fifth intercostal
space on the left midaxillary line.
During defibrillation apply firm pressure of at least 25 lb to each of
the paddles.
Automatic external defibrillator give shocks are recommended, for
pulseless Ventricular tachycardia or Ventricular failure only.
Implantable cardioverter-defibrillator (ICD) senses Ventricular
tachycardia or Ventricular failure and delivers 25 to 30 J shock up to four times,
if necessary.
An Implantable cardioverter-defibrillator is used in client with
episodes of spontaneous sustained ventricular tachycardia or Ventricular
failure unrelated to an MI or in client whose medication therapy has been
unsuccessful in controlling life-threatening dysrhythmias.
Client with implantable cardioverter-defibrillator avoid contact sports
to prevent trauma to the implantable cardioverter-defibrillator generator and
lead wires.
Nurse instruct the client with implantable cardioverter-defibrillator
to sit and lie down if he or she feels a shock and to notify the physician.
Client with implantable cardioverter-defibrillator avoid directly over
electromagnetic fields because it can inactivate the device.
Pacemakers is a temporary and permanent device that provides electrical
stimulation and maintains the heart rate when the client’s intrinsic pacemaker fails
to provide a perfusing rhythm.
Synchronised (demand) and asynchronous (fixed rate) are the two
settings of pacemaker.
Spikes is a straight vertical line which is seen on the monitor or electrocardiogram
strip when a pacing stimulus is delivered to the heart.
Non-invasive transcutaneous pacing, invasive transvenous pacing and
invasive epicardial pacing are the types of temporary pacemakers.
Nurse do not take the pulse or BP on the left side in a client with
pacemaker.
Client with pacemaker avoid the contact sports.
Nurse instruct the client to use cell phones on the opposite side of
the pacemaker.
Client with pacemaker always keep a pacemaker identification card in
the wallet and obtain or wear a medical-alert bracelet.
Angina is chest pain resulting from myocardial ischemia caused by
inadequate myocardial blood and oxygen supply.
Stable angina, unstable angina, variant angina, intractable angina and
preinfarction angina are the types of angina.
Stable angina is also called exertional angina. It occurs with
activities that involve exertion or emotional stress; relieved with rest or
nitroglycerin.
Unstable angina is also called preinfarction angina. It occurs with an
unpredictable degree of exertion or emotion and increases in occurrence,
duration and severity over time. Pain may not be relieved with nitroglycerin in
this angina.
Variant angina is also called Prinzmetal's or vasospastic angina. It
results from coronary artery spasm. It may occur at rest.
Intractable angina is a chronic, incapacitating angina unresponsive to
interventions.
Preinfarction angina associated with acute coronary insufficiency, and
last longer than 15 minutes. Symptoms of worsening cardiac ischemia are present.
It usually occurs after an MI, when residual ischemia may cause episodes of
angina.
After MI the troponin level is increase first than others.
The pain of MI client is relieved only by opioid, and pain may last 30
minutes or longer.
Dressler's syndrome is a combination of pericarditis, pericardial
effusion and pleural effusion, which can occur in several weeks to months
following a myocardial infraction.
Signs of pulmonary congestion, dyspnea, tachypnea, crackles in the
lungs, dry hacking cough, paroxysmal nocturnal dyspnea, increased blood
pressure (from fluid volume excess) or decrease BP (from pump failure) are the
signs of left-sided heart failure.
Depended edema of legs and sacrum, jugular venous distention,
abdominal distention, hepatomegaly, splenomegaly, anorexia and nausea, weight
gain, nocturnal diuresis, swelling of the fingers and hands, increased BP (from
fluid volume excess) and decrease BP (from pump failure) are the signs of right
sided heart failure.
Hypotension (BP lower than 90 mm Hg systolic or 30 mm Hg lower than the
client’s baseline), urine output lower than 30 mL/hr, cold, clammy skin, poor
peripheral pulses, tachycardia, pulmonary congestion, tachypnea, disorientation,
restlessness and confusion or continuing chest discomfort are the signs of
cardiogenic shock.
Central venous pressure (CVP) is the pressure within the superior vena
cava.
Normal central venous pressure is about 3 to 8 mm Hg.
During measuring central venous pressure the client needs to be supine, with the head of
the bed at 45 degrees.
The client is on a ventilator the reading of CVP should be taken at the
point of end-expiration.
Pulmonary artery wedge pressure (PAWP) is also known as pulmonary
artery occlusive pressure (PAOP).
Pulmonary artery wedge pressure normally ranges between 4 to 12 mm Hg.
Normal pulmonary artery pressure ranges from 15 to 26 mm Hg systolic/5
to 15 mm Hg diastolic.
Mean arterial pressure (MAP) is an approximation of the average
pressure in the systemic circulation throughout the cardiac cycle; used in
hemodynamic monitoring.
Mean arterial pressure must be at least 60 mm Hg for adequate organ
perfusion.
Pulmonary capillary wedge pressure is reflective of the left ventricular
end-diastolic pressure.
The pulmonary capillary wedge pressure normally ranges between 6 to 12
mm Hg.
Pain of pericarditis is grating and is aggravated by breathing (particularly
inspiration), coughing and swallowing.
Pain is worse when in the supine position and may be relieved by leaning
forward. Pericardial friction rub is heard on auscultation.
Endocarditis is the inflammation of the Inner lining of the heart and
values.
Client who had dental procedure in the previous 3 to 6 months has high
risk for endocarditis.
Splinter hemorrhage, Osler’s nodes, and Janeway lesions are seen in endocarditis.
Osler's nodes are reddish tender lesions on the pads of the fingers,
hands and toes.
Splinter hemorrhage is seen in the nail beds.
Janeway lesions are non-tender hemorrhagic lesions on the fingers,
toes, nose or earlies.
Pericardial effusion palaces the client at risk for cardiac tamponade.
Acute cardiac tamponade can occur when small volume 20 to 50 mL of
fluid accumulated rapidly in the pericardium.
Pericardiocentesis is the withdrawal of pericardial fluid.
Thromboembolism
is a problem occur following the valve replacement with a mechanical prosthetic
valve, and lifetime anticoagulant therapy is required.
Types of Venous thrombosis: (1) Thrombophlebitis: thrombus associated with inflammation. (2) Phlebothrombus: thrombus without inflammation. (3) Phlebitis: vein inflammation associated with
invasive procedure, such as IV lines. (4) Deep vein thrombophlebitis: More serious than a superficial
thrombophlebitis because of the risk of pulmonary embolism.
Red, warm area radiating up the vein and extremity, pain and soreness
or swelling are the signs ofphlebitis.
Calf or groin tenderness or pain with or without swelling. Positive Homans
sign. Warm skin that is tender to touch are the signs of deep vein thrombophlebitis.
Client with deep vein thrombophlebitis avoid prolonged sitting and
standing, wearing constructive clothing or cross legs when seated. Elevate the
legs for 10 to 20 minutes every few hours each day.
Prolonged venous hypertension is the main cause of venous insufficiency.
Legs elevation helps in return of blood to the heart in venous insufficiency.
Trendelenburg's test is performed to find out varicose veins.
Peripheral arterial disease, Raynaud’s disease and Buerger's disease
are the example of arterial disorders.
Raynaud's disease is vasospasm of the arterioles and arteries of the
upper and lower extremities.
Raynaud's disease affects primarily fingers, toes, ears and cheeks.
Buerger's disease is also called thromboangitis obliterans.
Buerger's disease is an occlusive disease of the median and small arteries
and vein.
The distal upper and lower limbs are affected most commonly in
Buerger's disease.
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