What is the most common cause of shock in children?
Hypovolemia, characterized by an overall decrease in circulating blood or fluid volume.
What are common causes of hypovolemic shock?
blood loss by trauma
diabetic keto acidosis
What is the cause of distrbutive shock?
It is a result of an abnormality in the distribution of blood flow or inability of the body to maintain vacular tone through vasconstriction.
What is the most common form of distributive shock?
Septic Shock, and occurs when microbial toxins (form bacteria, viruses, fungi or rickettsiae are presnet in the blood.
What do the toxins in the blood do during septic shock?
Cause a cascade of meabolic hemodynamin and clinical changes resulting in impaired organ perfuison and hypotension.
Which children are at greater risk or septic shock?
ones with debilitating illnesses and prolonged hospitalization in the ICU with many invasive lines
Give other forms of Distributive shock
central nervous injury
When does cardiogenic shock occur?
When myocardial function is impaired and cardiac output is not sufficient to meet the bodies metabolic demands.
What do you look for in cardiogenic shock?
Low cardiac output
diffrerent extremity B/P
poor tissue perfusion
poor response to fluid resuscitation
What causes cardiogenic shock?
Structual congenital abnormalities
infectious and noninfetious cardiomyopatheis
impaired cardiac function after heart surgery
How is cardigenic shock diffrent from hypovolemic shock
the compensatory mecehanism that occur in a child with CS my cause more heart damage. they take blood away from teh paeripheral splenci and mesnteric ciruclation to help maintain the vital organs.
General appearance Color
Looks good-Pink mucus membranes consistent color over the trunk and extremites
Looks bad- Mottled color gray or pale.
How do you diagnose Shock?
Chiefly on the basis of clinical manifestatons and medical history
What will the chest radiograph show in cardiogenic shock
Why is hypotension a late sign of shock?
Children can compensate for 25% blood loss with an increased heart rate.and peripheral vascular resistance.
How do you treat hypovolemic shock?
Circulation- infuse NS or LR
How do you treat Ditributive shock?
Restor hemodynamic status with fluid restriction
treat undelying cause
How do you treat for septic shock
Which side of the heart has less pressure?
The RIGHT side!!
18 to 30/0 to 5mm
Which blood has less oxygen content??
Venous (return blood)
What is the pressure in the left ventricle?
90 to 140/5 mm hg
What are the o2 sats in the left ventricle?
How does fetal circulation differ from neonatal circulation? (3 Ways)
THe process of gase exchange
the pressures within the systemic and pulmonary circulations
and the existaence of anatomic structures that assist in the delver of oxygent rich blood to vital organs.
For a fetus where does gas exchange?
In the placenta
In fetal circulation where is pressure higher right or left ventrical?
In fetal circulation they are Equal pressure.
What are the three fetel shunts?
What switches gas exchange from placenta to lungs?
Teh baby's first breath.
Why do the shunts close?
They close due to pressure change and increased O2 content of the blood.
How long does it take for fetal shunts to close?
May take several days.
Cardivacular alteration is childresn are either?
where is the usual site for Cardiac Catheterization?
What is the etiology of Congenital Heart Disease?
but may be linked to
smoking during pregnancy
exposure to chemicals
What genitec conditions increase risk for CHD?
Turner syndrome (Girls)
What is Shunt?
Abnormal blood flow form one part of the circulatory system to another.
What is heart failure?
The hearts inability to circulate blood to maintain sufficeient cardiac output to meet the metabolic demands of the body.
How the does the heart intialy responed in Heart failure?
Increases heart rate. over time the heart may become enlarged (cardiomegaly) causing the wall muscles to grow weak and inefficient.
What happens when the heart muscles become weak?
can reduce blood volume in the body which causes the body's arteries to constict and for the heart to work even harder. and can lead to pulmonary edema.
What are the subtle symptoms in early CHF?
Tachypnea (70-80 breaths)
diaphoresis during feeding
dyspnea during feeding
abnormal cardic rythm gallop
periorbital and facial edema n
neck vein distention
decreased peripheral perfusion
decreased urine output
mottling and cynosis, pallor
If a Hf baby exhibits diaphoresis and complain of decreased appetite what can cause this?
Chornic abd pain usually related to poor circulation and decreased perfusion to abd organs.
Why should you use O2 with caution in children with left to right shunts?
Because oxygen is a vasodilator it may increase pulmonary blood flow.
If the child has not been able to decrease symptoms and achieve weight gain what would you do?
What can increase the risk for digoxin toxicity?
What is pulmonary hypertension?
Elevated blood pressure in the blood vessels of the lungs
Diagnosesd when pressure is>25 mmhg
What is the most common cause PAH
How long does it take for PAH to occur?
Over time when vascular changes eventually lead to vessle wall thickening severe irreversible vasoconstriction and vascular obstruciotn. causes a reversal of cardiac shunting and become right to left. (Eisenmenger syndrome)
What is used to treat PAH in newborns?
Inhaled nitric oxide because it is an effective pulmonary vasodialator.
Give types of Congenital Heart Disease? CHD
Acyanotic (L to R shunt)
atreial septal defect
Lesions including pulmonary stenosis, aortic stenosis, coarctation of
the aorta, and interrupted aortic arch
Types of CHD (cont)
•Cyanotic Lesions (R to L shunt)
of the great arteries
What is the gold standard for cardiac therapeutic modalities
Cardiac Catherterizaton it usually constitutes teh final definitive diagnostic test for many patients.
Complications to be aware of in cardiac cathererization?
reaction to the dye
How can you tell if there is a thrombus in the venous system?
swelling and inflamation to the affected limb
How can you tell there is a thrombus in the arterial system?
Coolness or dicoloration of the extremity and loss of pulses distal to the thrombus.
How is the patient positoned after cardiac catherezation?
positioned with the affected leg straight for 4-6hrs. Infants my be held prone on a parents lap. older children remain in bed with a 20 degree incline only.
How should you assess for bleeding in a cardiac cath child?
Not only on the dressing but on the sheets look for pooled blood under the child, remove diaper if needed.
What should you do if a cardiac cat patient is bleeding?
Apply pressure for 10-15 min and assess distal perfusion, notifiy the physician
How soon can a cath kid return to school?
After the third day.
Patent Ductus Arteriosus (PDA)
Left to rigth shuntin Lesions
O2 in the infant’s blood causes the ductus arteriosis to constrict in 10-18 hrs. after birth.
This doesn’t happen 10-15% of the time and results
in a PDA
S/S of PDA
Continuous murmer- machiner like sound
Widened pulse pressure (increased differecnce between systolic and diastolic readings
Medical managment of PDA?
Interventions to address heart failure
admin of indocin- a PG inhibitor that constricts the ducts
Interventions Cardiac cath
a coil is place to occlude the ducts, tissue grows around the coil forming a permanent occlusion
Ligation of the ductus via left thoracotomy usually within the first year of life
Atrial Septal Defect (ASD)
ASD causes increased size of R
atrium and increased pulmonary blood flow and often closes on its own.
Ventricular Septal defect (VSD)
20-80% close on their own.
Decrease in pulmonary vascular resistance compared to systemic vascular resistance in the weeks after birth results in left to right shunting through the VSD
Increased pulmonary blood flow
Progressive pulmonary vascular disease can occur over time.
S/s of VSD?
Some children remain asymptomatic
Loud, harsh systolic murmur varies in intensity and duration depending on degree of shuntin and size of defect palpable thrill
diastolic murmru and gallop rhythm may be present
HF may occur with moderate to large defects
Sugical managment of VSD?
Suture or patch closure using open heart surgery with cardiopulmonary bypass
Consideration of pulmonary artery banding to reduce pulmonary blood flow
Pulmonay stenosis (narrow entrace to the pulmonary artery usually at the valve)
S/S of obstructive/stenotic lesions
in symptomatic children
signs of right-sided HF
systolic ejection murmur
possible palpable murmur
cardiomegaly on radiograph
cyanosis in severe cases
Narrowing of the entract to the aorta may b supravalvular, subvalvular or at the valve level (most common) thickend rigid with some fusion of the leaflets the valve may be bicuspid
What is Tetrology of Fallot (TOF)
Most common cyanotic lesion seen in
yr. of life
•Includes 4 defects
ventricular hypertrophy (due to the pulmonary stenosis)
Tricuspid atresia (infant has
cyanosis within few hrs. after birth)
•Pulmonary atresia (profound
•Hypoplastic L heart (95% die if untreated
within the 1st
months of life)
•Transposition of the great vessels
(mixing lesion). Often accompanied by
Surgery in Pediatrics
Trend is to do the surgery early
•Closed heart surgery includes
repair of a PDA, coarctation of the aorta, & some aorta to
•Open heart surgery is done for ASD,
VSD, Tetrology of Fallot,
and some other defects.
These are not present at birth;
however, if the child has CHD then they may develop acquired heard disease
(i.e. dysrrhythmias & endocarditis)
Heart Disease includes
Factors that play a role in acquired heart disease is?
What is Infective Endocarditis
Infective endocarditis IE is an inflammation resulting from infection of the cardiac valves and endocardium by bacterial or occasionally a fungal viral agent.