Cardiovascular Assessment Flashcards
1
Q
What is the main focus of the CV exam?
A
auscultation
2
Q
What features can be assessed of the CV exam via auscultation?
A
HR, rhythm, regularity and heart sounds
3
Q
What implication does the change from fetal-placental to newborn-lung circuitry mean for the clinician?
A
the findings of the CV exam constantly change over the first few hours, days and weeks of life
4
Q
Ideally, when should an newborn CV assessment be done?
A
shortly after birth, at 6-12 hours of age, at 1-3 dol and at regular intervals thereafter
5
Q
At a minimum, when should an newborn CV assessment be done?
A
shortly after birth, at one dol and at regular pediatric office visits
6
Q
What maternal conditions are known to increase the incidence of CHD?
A
maternal diabetes, systemic lupus erythematosus and a maternal h/o CHD
7
Q
What is the cumulative risk of CHD in the neonate born to a diabetic mother?
A
3-4x that for the general population
8
Q
What is the prevalence of CHD (for truncus, transposition, TOF, AV canal & HLHS) in the US?
A
0.82-4.73 per 10k live births
9
Q
What are the most commonly seen CHD in infants born to diabetic mothers?
A
VSD, CoA and transposition
10
Q
What are the most commonly seen CHD in infants born to mothers with systemic lupus erythematosus?
A
congenital complete AV block
11
Q
How does a congenital complete AV block present?
A
low resting HR; sometimes in utero as well
12
Q
What is the cumulative risk of a mother with CHD having a baby with CHD?
A
10-15% risk
13
Q
What months of the pregnancy are especially important to identifying CHD?
A
first 2 months, when the heart is forming
14
Q
What might be the result of a maternal viral infx in the last two weeks prior to delivery?
A
acute myocarditis in the neonate
15
Q
What drugs are known to carry a risk of CHD when taken during pregnancy?
A
amphetamines, lithium, phenytoin sodium, thalidomide, retinoic acid, valproic acid and alcohol
16
Q
What is the risk of recurrence if a child is born with CHD in subsequent pregnancies?
A
1-5%
17
Q
In what birth weight class is there an increased incidence of CHD?
A
LBW
18
Q
What are commonly associated CHD with a maternal history of rubella?
A
PDA, PPS, septal defects
19
Q
What are commonly associated CHD with a maternal history of phenylketonuria?
A
TOF
20
Q
What are commonly associated CHD with a maternal history of alcohol abuse?
A
septal defects
21
Q
What are commonly associated CHD with a maternal history of hydantoin?
A
pulmonary and aortic stenosis, CoA and PDA
22
Q
What are commonly associated CHD with a maternal history of lithium?
A
Ebstein’s malformation, tricuspid atresia and ASD
23
Q
What are commonly associated CHD with a maternal history of retinoic acid?
A
defects of ventricular outflow tracts
24
Q
What are commonly associated CHD with a maternal history of trimethadione?
A
ToF, complete transposition and HLHS
25
What are commonly associated CHD with a maternal history of thalidomide?
ToF, septal defects, truncus
26
What are commonly associated CHD with de Lange syndrome?
VSD, ASD, PDA, aortic stenosis and endocardial fibroelastosis
27
What are commonly associated CHD with Holt-Oram heart-hand syndrome?
ASD secundum, VSD or PDA in 2/3, conduction block, HLHS, TAPVC and truncus
28
What are commonly associated CHD with Marfan syndrome?
aortic aneurysm, aortic regurg, mitral regurg, tricuspid regurg, prolapse
29
What are commonly associated CHD with Noonan syndrome?
pulmonic stenosis/dysplasia, hypertrophic cardiomyopathy, PDA, CoA
30
What are commonly associated CHD with Carpenter syndrome?
PDA, PS, VSD, ToF, transposition and ASD
31
What are commonly associated CHD with Ellis van Creveld syndrome?
single atrium, primum ASD, CoA and HLHS
32
What are commonly associated CHD with Mucopolysaccharidosis type 1 syndrome?
valvular disease in all types
33
What are commonly associated CHD with trisomy 21?
AV canal, VSD, PDA, ASD and ToF
34
What are commonly associated CHD with trisomy 18?
VSD, polyvalvular disease, ASD, PDA
35
What are commonly associated CHD with trisomy 13?
PDA, VSD, ASD, CoA, aortic stenosis and pulmonic stenosis
36
What are commonly associated CHD with Turner syndrome?
CoA, bicuspid aortic valve, aortic aneurysm, aortic stenosis and VSD
37
What are commonly associated CHD with Beckwith-Wiedemann syndrome?
hypertrophic cardiomegaly, ASD, VSD, PDA, ToF
38
What are commonly associated CHD with Charge association?
ToF, DORV, ASD, VSD, PDA, CoA and AV canal
39
What are commonly associated CHD with DiGeorge syndrome?
IAA, truncus, ToF, right aortic arch
40
What are commonly associated CHD with VACTERL association?
VSD, ASD, ToF
41
What are commonly associated CHD with Williams-Beuren syndrome?
supravalvar aortic stenosis, stensosi of the left coranory artery, small aorta, multiple pulmonary arteries, cerebral and rental arteries
42
What are commonly associated CHD with cleft lip/palate presentation?
VSD, PDA, transposition, TOF and single ventricle
43
What are commonly associated CHD with a CDH?
ToF
44
What are commonly associated CHD with an omphalocele?
ToF, ASD
45
What are commonly associated CHD with intestinal atresia?
VSD
46
What are commonly associated CHD with renal agenesis unilateral or bilateral?
VSD
47
What is the incidence of extracardiac comorbidities in an infant with CHD?
25%
48
What body systems are likely to present with an extracardiac anomaly in an infant with CHD?
neurologis, GI, TEF, renal and urogenital irregularities and CDH
49
What is meant by "centrally pink" in appearance?
general color as well as lips, tongue, earlobes, nail beds and scrotum
50
What is the best indicator for determining central cyanosis?
the tongue due to its rich vascular supply and lack of pigmentation
51
What should be suspected of an infant that appears pink at rest, but becomes deep red to purplish when crying?
polycythemia
52
What is polycythemia?
central hematocrit >65
53
Are infants with polycythemia cyanotic?
even though they appear cyanotic, they rarely are
54
Why do infants with polycythemia appear cyanotic?
the ruddy or reddish color may be mistaken bc newborns who have increased hgb usually have increased amounts of hgb. And therefore, a higher likelihood that there will be a larger percentage of unbound hgb. The unsaturated hgb masks the saturated.
55
What is central cyanosis?
bluish color of the skin, lips, tongue, ear lobes, scrotum and nail beds in infants with significant arterial oxygen desaturation
56
When does central cyanosis become visible?
When there are at least 5g of hgb per 100mL of blood not bound to oxygen
57
What should peripheral cyanosis be considered in a normal newborn?
normal until about 2 dol
58
What is the reason for peripheral cyanosis in a newborn in the first 48h of life?
vasomotor instability
59
What are possible etiologies for central cyanosis?
lung dz, sepsis, PPHN or neurologic dz
60
What are the two best indicators of CHD?
cyanosis and symptoms of congestive heart failure
61
What is the response of an infant with CHD to the hyperemia test?
cyanosis that does not improve upon administration of 100% FiO2 is most likely the result of cardiac causes, as is cyanosis that increases with crying
62
Why might an infant with a compromise cardiac state appear pale?
as the result of vasoconstriction and the shunting of blood away from the skin to more vital organs
63
What might mottling indicate?
amy be a sign of cardiogenic shock when a/w hypovolemia or decreased cardiac output
64
Why might a hypoxic, anemic infant not appear cyanotic?
because hgb levels may be too low to produce a bluish color
65
Where should cap refill be assessed?
both centrally and peripherally
66
What cap refill time is considered abnormal?
When delayed >3-4 seconds
67
What is the typical presentation of congestive heart failure?
signs of respiratory distress- G/F/R, tachypnea and crackles
68
How typical is edema presenting with a cardiac anomaly?
rarely
69
What should be considered if an infant presents with non-labored respiratory effort and cyanotic?
the cyanosis is most likely the result of a congenital heart defect that restricts pulmonary blood flow
70
Pulses represent an approximate determination of what cardiac feature?
cardiac output
71
What pulse may not be appreciated in the normal newborn, which is considered a normal finding?
dorsalis pedis
72
What is a pulse deficit?
a difference between the HR counted with a pulse and a HR counted on auscultation
73
In what circumstances is a pulse deficit most likely to present?
with ectopic rhythms
74
At a minimum, what pulses should be assessed and how?
the femoral and brachial; palpated BL and then one femoral and the right brachial palpated simultaneously
75
Why should the right brachial pulse be palpated instead of the left?
because the right subclavian artery is always pre ductal, but the left subclavian artery may or may not be preductal
76
What might absent or weak femoral pulses indicate?
(especially in comparison to the R brachial) are abnormal and may indicate decreased aortic blood flow as seen with CoA, aortic stenosis and HLHS
77
What might a bounding pulse indicate?
usually present with a PDA and other aortic runoff lesion (truncus, aortic regurg and systemic arteriovenous fistula)
78
What might weak or absent peripheral pulses indicate?
low cardiac output from an cause, especially a left heart obstructive lesion
79
Why is an active precordium a normal finding in a term newborn for the first few hours of life?
there may be a visible impulse noted along the lower left sternal border because of the right ventricular predominance common to transitional circulation
80
When a bounding precordium is observed in a term infant after the first few hours of life, what should be suspected?
this is typical of heart disease, likely a defect with increased ventricular volume work (L>R shunt lesion- PDA/VSD) or severe valvular regurg
81
Why is an active precordium typical in preterm infants?
because of decreased subcutaneous tissue
82
What is the apical impulse?
the forward thrust of the left ventricle during systole
83
Where is the location of the apical impulse (typically)?
fourth intercostal space, either at or to the left of the midclavicular line
84
What should be suspected if the apical impulse is located downward and to the left?
left ventricular dilation
85
What should be suspected if a very sharp apical impulse is found?
high cardiac output or left ventricular hypertrophy
86
The PMI and apical impulse are usually the same, but not always during the first hours-days of life. During this time, where can an impulse stronger than the apical impulse be found?
fifth intercostal space at the lower sternal border or even substernally
87
Why might the PMI and the apical impulse not be in the same location for a normal newborn?
because of the right ventricular predominance found in transitional circulation
88
In what physiologic states might the PMI be displaced?
dextrocardia, tension pneumo and CDH
89
What is the best way to palpate a heave, tap or thrill?
palpating with the portion of the palm at the base of the fingers instead of with the fingertips; vibratory sensations are best felt with the ulnar surface of the hand
90
What is a heave and what is it commonly associated with?
a PMI that is slow rising and diffuse; a/w volume overload
91
What is a tap and what is it commonly associated with?
a sharp, well-localized PMI; a/w pressure overload; a hypertrophied but not dilated right ventricle produces a distinct parasternal tap
92
How are thrills described when appreciated in the newborn exam?
low-frequency, palpable murmurs that feel similar to touching a purring cat
93
How do thrills relate to murmurs?
a thrill denotes a loud murmur (at least Grade IV); not common
94
If a thrill is appreciated in the upper left sternal border, where does it originate in the heart and what conditions are associated with this presentation?
originates from the pulmonary valve or pulmonary artery and may be associated with pulmonary stenosis, TOF or rarely, PDA
95
What is the normal range of a term neonate's HR at rest?
between 100-160
96
At sleep, what values can be anticipated for a term neonate?
as low as 70bpm
97
What is sinus bradycardia?
a HR <80bpm; a common transient finding in both term and preterm infants
98
What is the underlying physiologic etiology for sinus bradycardia in the newborn?
the predominance of the parasympathetic system
99
What actions may cause vagal stimulation and what is their effect?
yawning, stooling or suctioning; subsequent bradycardia
100
How should sinus bradycardia be treated if caused by vagal stimulation?
these episodes are usually transient, require no treatment and are self-correcting; in preterm infants may require intervention
101
What is sinus tachycardia?
a HR >180-200bpm (greater than normal for age)
102
What is the most common form of rapid HR in the neonate?
sinus tachycardia
103
What are possible etiologies for sinus tachycardia in the newborn?
crying, feeding, fever or activity; any activity that increases demands on the heart
104
How should sinus tachycardia be treated?
normally, with removal of the stimulus, the HR slowly returns to baseline; rarely requires treatment
105
How should HR variation in a newborn be interpreted?
normal, a positive sign of the infant's ability to react to the environment
106
What does the term SVT encompass?
paroxysmal atrial tachycardia and atrial flutter and fibrillation
107
How should the presentation of SVT in the newborn be interpreted?
as a medical emergency and requires immediate intervention
108
Why is SVT considered a medical emergency?
at such rapid HR, cardiac output is extremely compromised because of shortened diastolic filling time
109
Without intervention, what is the anticipated prognosis of an infant with sustained SVT?
without treatment, decreased cardiac output will cause congestive heart failure within 48 hours and possibly death
110
What are the treatment options for SVT?
treatment for SVT depends on the cause, but the condition may respond of vagal stimulation, chemical cardioversion or cardioversion
111
When evaluating an infant for the rhythm and regularity of heart sounds, what features should be noted?
patterns and frequencies of the irregularity to help identify the type of arrhythmia
112
Whenever an arrhythmia is suspected, what course of action should be taken to establish a diagnosis?
a EKG and/or continuous heart monitoring
113
What is sinus arrhythmia?
a very common, normal variant in most newborns and is associated with respirations
114
How is sinus arrhythmia characterized?
by irregularity if the R-R interval, with an otherwise normal cardiac cycle
115
How should a sinus arrhythmia be treated?
no treatment is required for this rhythm
116
What are premature atrial beats?
an early beat arising from a supra ventricular focus, ventricular conduction is normal
117
How should the presentation of premature atrial beats be interpreted in the newborn?
almost always benign; may be abnormal when seen with CHD, sepsis, hypoxia, hyperthyroidism, cardiac tumors, myopathies, electrolyte abnormalities, digoxin toxicity, administration of caffeine, atropine, theophylline or inotropic agents and severe respiratory distress
118
How should premature atrial beats be treated?
if significant, treat the underlying cause, but beats are usually well tolerated and no treatment is indicated
119
What are premature ventricular beats?
early beat arising from an irritable ventricular focus, ventricular conduction will be abnormal
120
How is a premature ventricular beat seen in an EKG tracing?
a wide and bizarre QRS complex
121
What are possible causes of premature ventricular beats in the newborn?
hypoxia, irritation by an invasive catheter or surgical procedure or CHD
122
How should premature ventricular beats be interpreted in the newborn?
treatment is unnecessary if the phenomenon is infrequent
123
What does S1 represent?
the first heart sounds represents the closure of the mitral and tricuspid valves at the onset of ventricular systole
124
Where is S1 best appreciated?
should be heard most loudly at the apex of the heart
125
What is the typical intensity of the S1 heart sound?
S1 is usually loud at birth, decreasing in intensity during the first 48h of life; any factor that increases cardiac output also increases the intensity of S1
126
What is splitting?
hearing two distinct components of a heart sound
127
What causes heart sound splitting?
the asynchronous closure of the two valves that create the heart sound
128
Why is splitting typically difficult to distinguish?
the infant's rapid HR; S1 is usually described as being single
129
What does S2 represent?
closure of the aortic and pulmonic valves
130
Where is S2 best appreciated?
should be heard most loudly at the base of the heart
131
How should S2 splitting be interpreted in the newborn?
usually sinlge at birth, but it is split in 66% of infants by 16h of age and in 80% of infants by 48h
132
How should wide S2 splitting be interpreted in the newborn?
abnormal; can occur with ASD, pulmonary stenosis, Ebstein's anomaly, partial anomalous pulmonary venous return, mitral regurg or right bundle branch block
133
What does S3 represent?
most often signifies rapid or increased flow across the AV valves (rapid ventricular filling) and is commonly heard in premature infants with a PDA- rarely heard with overt congestive heart failure
134
Where is S3 best appreciated?
can occasionally be heard in infancy; best heard at the apex of the heart during early diastole
135
Where is S4 best appreciated?
rarely heard in neonates; heard at the apex of the heart and is a low pitched sound of late diastole
136
How should the appreciation of S4 be interpreted?
always pathologic and is heard in conditions characterized by decreed compliance (especially cardiomyopathy) or congestive heart failure
137
What does decreased compliance mean when referring to the heart?
refers to the myocardium that is relatively stiff and therefore does not expand well as the blood enters the chambers
138
How does decreased myocardial compliance affect cardiac function?
a stiffened myocardium with a limited ability to expand affects the volume of blood that is ejected by the heart with contraction
139
How is an ejection click described?
snappy, high frequency sound best heard after the first heart sound
140
When do ejection clicks occur in the cardiac cycle?
at the time of ventricular ejection and resemble in timing, but not quality, a widely split S1
141
When are ejection clicks commonly heard and why?
any time after the first 24h of life and are usually normal in that time r/t pulmonary hypertension seen with transitional circulation; any time after 24h they are considered abnormal
142
What are the most commonly associated pathologic findings with ejection clicks persisting after 24h of life?
aortic or pulmonic stenosis, idiopathic dilation of the pulmonary artery, systemic or pulmonary hypertension, truncus or TOF
143
What causes a murmur?
caused by turbulent blood flow and described as prolonged heart sounds
144
What are the two classifications of murmurs?
innocent and pathologic
145
What is the difference between innocent and pathologic murmurs?
pathologic murmurs result from underlying cardiovascular disease, innocent murmurs do not
146
What features of a murmur should be assessed?
timing, location, intensity, radiation, quality and pitch
147
Why is the neonate's age in hours important for the evaluation of a murmur?
the age in hours is also especially significant because of the dynamic properties of the newborn heart
148
What is the first quality of the murmur to be evaluated?
timing
149
What is systole?
the period when the heart contracts and the heart chambers eject blood
150
When does systole occur in the heart cycle?
occurs following closure of the mitral and tricuspid valves and its onset occurs just after S1
151
What is diastole?
the period when the heart is relaxed and the chambers are filling with blood
152
When does diastole occur in the heart cycle?
following the closure of the aortic and pulmonic valves and its onset occurs just after S2
153
What is holosystolic?
pansystolic, occurs throughout systole
154
When are continuos murmurs appreciated?
through both systole and diastole
155
How is intensity graded?
loudness, or intensity, or the murmur is graded on a scale I-VI
156
What is a Grade I murmur?
barely audible, audible only after a period of careful auscultation
157
What is a Grade II murmur?
soft, but audible immediately
158
What is a Grade III murmur?
of moderate intensity but NOT associated with a thrill
159
What is a Grade IV murmur?
louder, may be a/w a thrill
160
What is a Grade V murmur?
very loud, can be heard with the stethoscope rim barely on the chest, may be a/w a thrill
161
What is a Grade VI murmur?
extremely loud, can be heard with the stethoscope just slightly removed from the chest, may be a/w a thrill
162
Why might the intensity of a murmur vary from exam to exam?
changing PVR or other factors that alter the status of cardiac output such as anemia, activity or changing ventilatory requirements
163
How is the location of a murmur typically described?
in terms of the interspace and the midsternal, midclavicular or anterior axillary lines
164
Why is describing a murmur in terms of aortic, pulmonic, tricuspid or mitral areas not recommended?
because of possible malposition of valves and vessels consistent with CHD
165
What is radiation (or transmission) of a murmur?
other locations where a murmur is heard
166
Where is the murmur from a normally positioned pulmonary outflow tract transmitted?
left upper back
167
Where is the murmur from a normally positioned aortic outflow tract transmitted?
the carotid arteries
168
How is the pitch of a murmur typically described?
as high, medium or low; quality can be described as harsh, rumbling or musical
169
When does a high pitched murmur occur?
when there is turbulence from a high pressure to a low pressure area; can happen with aortic or mitral insufficiency
170
When does a low pitched murmur occur?
when there is a low pressure difference in the turbulent blood flow; can happen with mitral stenosis
171
During the first 48h of life, what is the type of commonly presenting murmur in an asymptomatic newborn?
many newborn have murmurs, the majority of which are innocent; usually a/w decreasing PVR and gradual closure of the PDA
172
How are innocent murmurs graded and evaluated?
sometimes called flow murmurs, grade I-II; a/w normal EKG and CXR findings and typically systolic
173
What are some of the more common innocent murmurs heard during the first 48h of life?
systolic ejection murmur, continuous systolic or crescendo systolic murmur and early soft mid systolic ejection murmur
174
What is location and typical description of a systolic ejection murmur?
in 56% of normal babes, Grade I-II/VI, best heard along the mid and upper left sternal border and described as vibratory
175
When do systolic ejection murmurs typically present?
within the first sol and may last as long as 1 week
176
What is the most likely cause of a systolic ejection murmur?
the result of the significant increase in flow across the pulmonary valve a/w rapidly decreasing PVR
177
What is location and typical description of a continuous systolic or crescendo systolic murmur?
15% of normal babes, Grade I-II/VI, heard best in the upper left sternal border
178
When do continuous systolic or crescendo systolic murmurs typically present?
within the first 8h of life
179
What is the most likely cause of a continuous systolic or crescendo systolic murmur?
by the transient L>R flow through the DA during the period when PVR is falling but ductal closure has not yet been established
180
What are other names for an early soft mid systolic ejection murmur?
peripheral pulmonic stenosis, pulmonary flow murmur or pulmonary branch murmur
181
What is the location and typical description of an early soft mid systolic ejection murmur?
heard often in newborn, especially preterm, Grade I-II/VI, medium to high pitched; heard best in the upper left sternal border with wide radiation to both lung fields, axillae and back
182
When do early soft mid systolic ejection murmurs typically present?
within the first week or two of life, persist for weeks to months but generally disappear by 3-6 mo
183
What is the most likely cause of an early soft mid systolic ejection murmur?
result from the turbulence produced at the relatively acute angle of the bifurcation of the pulmonary artery
184
Why is there variation in the presenting times of pathologic murmurs?
depending on the abnormality causing them and no normal circulatory changes a/w transitional circulation
185
What are the majority of pathologic murmurs appreciated in the delivery room attributed to and why?
almost always caused by either stenosis or regurg; almost never the result of shunting bc vascular resistance in the lungs and body are equal at birth
186
Why do many pathologic murmurs of specific defects not present until day 3, 1 week or 4-6 weeks of age?
because this is when the PVR has fallen sufficiently
187
How should the absence of a murmur be interpreted?
the absence of a murmur does not exclude the potential for serious CHD; may be an ominous sign in both cyanotic and acyanotic ductal dependent lesions
188
When might ASD present?
sometimes do not present until 1-2 years of age
189
What percentage of infants die from CHD during the first month of life do not have heart murmurs?
20%
190
Describe the presentation of a newborn in the nursery that warrants further CV assessment?
a murmur heard after 48h of life, louder than Grade I-II/VI in a symptomatic infant
191
What is included in a full CV work up?
CXR, EKG and cardiologist consult
192
What are the most commonly occurring pathologic murmurs in the immediate postnatal period?
a loud systolic ejection murmur and a continuous murmur; may occasionally be heard with mitral and tricuspid insufficiency (especially left ventricular failure in infants with critical left ventricular outflow obstruction and TOF)
193
What is the typical presentation of a loud systolic ejection murmur?
usually Grade II-V, appearing within hours of birth
194
What is the cause of a loud systolic ejection murmur?
almost always the result of aortic or pulmonary stenosis or CoA
195
What is the prevalence of a continuous murmur?
occuring in 1/3 of premature infants with a PDA (may only be systolic)
196
What is the cause of a continuous murmur?
AV fistulas regardless of GA
197
When will a pathologic murmur a/w VSD and PDA in term neonates present?
not until PVR has fallen, often not until after discharge or at several weeks of age
198
When will the liver become engorged?
with increased central venous pressure;
199
What is a good indicator of right sided heart failure in a term infant?
a liver located more than 3cm below the right costal margin
200
What are the best practices regarding systemic BP monitoring?
should be measured in every neonate with suspected CHD, renal dz or clinical signs of hypotension
201
How is the BP value affected by a cuff that is too small for the patient?
generate a hypertensive value
202
What is the appropriate cuff width in a BP test?
width is 40-50% of the circumference of the extremity or 25-55% wider than the diameter of the limb being measured
203
How is systemic BP obtained via the flush method?
a hand or foot is squeezed until it blanches, then the cuff is rapidly inflated. The pressure is slowly released and the pressure point at which the extremity "flushes" represents the MAP
204
How is systemic BP obtained via the palpation method?
while releasing the pressure in the cuff, the examiner palpates a distal pulse. The pressure point at which the pulse returns approximates the systolic pressure
205
How is systemic BP obtained via the ultrasound method?
a transducer is placed over an artery distal to the cuff and an audible pulse is listened for after deflating the cuff. The pressure point at which a beat is heard approximates the systolic pressure
206
What affects the normal blood pressure values in newborns?
values vary depending on BW and postnatal age; in the first few hours, BP is affected by type of delivery, birth asphyxia and placental transfusion
207
Why does a newborn's initial BP decrease during the first 3-4h of life?
r/t fluid shifts into and out of the vascular space
208
What is the trend of systolic values following birth?
reaches a nadir at 3-4h of age and then gradually increases to reach a plateau at 4-6 dol to a level closer to the initial postpartum level
209
What external factors affect BP values?
activity, temperature and behavioral state
210
When should an examiner obtain 4 extremity BP values?
suspected CHD, difficulty obtaining BP, appreciation of a murmur or absent femoral pulses
211
How do BP values in the lower extremities relate to those from the upper extremities?
lower extremities are often higher, but can be equal or slightly lower
212
Why should a left upper extremity BP not rule in or out a CoA?
a pressure difference can be masked by a PDA that allows blood to pass around the restricted area; therefore the right arm is preferred as it is always preductal
213
What is a pulse pressure?
the difference between the systolic and diastolic blodd pressures
214
What is the average value for a pulse pressure?
term: 25-30; preterm: 15-25
215
How should a widened pulse pressure be interpreted?
may indicate a large aortic runoff, as seen with PDA
216
How should a narrow pulse pressure be interpreted?
may have peripheral vasoconstriction, heart failure or low cardiac output
