Transcript 2-cyanotic congental heart diseases

Cyanotic congenital heart
disease
Case Presentation
• Term male infant delivered by
spontaneous vaginal delivery and appears
cyanotic at birth
• respiratory rate 70 bpm, baby has grunting
and nasal flaring with chest retractions
• Heart murmur on exam
• ABG: pH 7.32 PaCO2 45 PaO2 35
Case Presentation
•
•
•
•
What is happening?
Have you seen this problem?
What is causing her problem?
What can we do about it?
Cyanosis defined
• Bluish discoloration of skin or mucous
membranes
• Presence of 5g/dL of deoxyhemoglobin
• Low flow areas with increased oxygen
extraction have more deoxyhemoglobin
• High flow areas with less extraction
should not have enough
deoxyhemoglobin to appear cyanotic
– Under normal circumstances you should not be able to
extract enough O2 to have 5 g/dL deoxyhemoglobin running
through the tongue and gums (lips OK when cold)
Cyanosis: Peripheral v. Central
• Peripheral
– Response to cool
temperatures
– part of normal transition
– may last 72hr
– May also represent poor
cardiac output
• poor perfusion
• anemia
• Central
– Multiple causes
Cyanosis
Cyanosis
Cyanosis
100
90
80
% Saturation
• Cyanosis is dependent
on HCT and % Sat
• Florescent light makes
cyanosis hard to see.
• Except in the extreme,
cyanosis is not obvious
• Look at the the tongue
and the gums
• Any question, check a
pulse ox
70
60
50
40
30
20
10
0
0
20
40
HCT
60
80
Terms
• Oxygen tension (PO2)
– Partial pressure of oxygen in the blood (mm Hg)
– Measured on an ABG machine
– Oxygen dissolved in plasma
• 0.003 ml O2/mm Hg/dl plasma
• Oxygen saturation (SO2)
– Amount of oxygen actually combined with
hemoglobin as a percent of total oxygen that could
be bound to hemoglobin
– Measured by saturation monitor (pulse-oximeter)
– ~1.34ml O2/g Hb
Oxygen-Hemoglobin Dissociation Curve
• Allows for nearly full
saturation of Hb at
reduced PO2
• Left shift
– alkalosis, fetal Hb
• Right shift
– acidosis, hypercarbia,
hyperthermia
Differential Diagnosis of
cyanosis
1. Not enough oxygen in
2. Oxygen “mal-absorption”
3. Too much oxygen out
Not enough oxygen in
• Apnea
– neurologic and drugs
• Diffusion barrier
– RDS, aspiration, pneumonia
• Obstruction
– pneumothorax, head position
Oxygen “mal-absorption”
• Shunting lesions
– cardiac
– non-cardiac (like PPHN)
• Hematologic
– methemoglobinemia
– carboxyhemoglobinemia
Too much oxygen out
• High oxygen consumption
– sepsis
– low flow, high extraction
• acrocyanosis
• hyperviscosity/polycythemia
• extravasated (e.g. bruising)
Neonatal Circulation
•Baby separated
from placenta
•Baby breathes and
lungs expand
•Closure of ductus
arteriosus and
foramen ovale
Persistent Pulmonary
Hypertension
High resistance in
pulmonary vessels
Persistent R  L
shunts
• ductal
• atrial
• intra-pulmonary
Poor heart function
The Five Ts of Cyanotic Congenital
Heart Disease
• Transposition of the great
arteries
• Tetralogy of Fallot
• Truncus arteriosus
• Total Anomalous Pulmonary
Venous Return
• Tricuspid Atresia
Normal Anatomy
• normal
Tetralogy of Fallot (TOF)
• Overriding Aorta
• Ventricular
septal defect
• Pulmonary
stenosis
• Right ventricular
hypertrophy
Tetralogy of Fallot
• Boot
shape
– RVH lifting
apex
– loss of PA
knob
Fallots with
pulmonary
atresia
Blue. Will need a •
systemic- pulmonary
shunt.
Transposition of Great Arteries - no
PPHN
Comfortably •
tachypneic
(usually big)
child with
oxygen
saturation 50-6% on room air or
oxygen
Transposed
Great Arteries
• Blue. Presents with
cyanosis when the
duct closes.
Transposition of Great
Arteries
• Egg on a
string
– alignment of
PA and Ao
narrows the
mediastinum
Total Anomalous Pulmonary
Venous Return (TAPVR)
• Type 1
(supracardiac)
– 50% with snowman
– can have UE<LE
saturation
• Type 2 (cardiac)
• Type 3
(infracardiac)
– all can obstruct,
infracardiac almost
always does
Totally anomalous pulmonary
venous drainage
(infradiaphragmatic)
All four pulmonary •
veins drain to the right
side. Below the
diaphragm they are
always obstructed.
Infant presents in first
days with cyanosis,
circulatory and
respiratory failure and
collapse.
Total Anomalous Pulmonary
Venous Return
• Snowman
Ebstein’s
anomaly
• The tricuspid valve is
abnormal and inserts
well down into the RV.
There is often severe
trisuspid regurgitation,
which can lead to
death in the fetus or
infant. Usually also with
ASD so right-to-left flow
results in cyanosis.
Wall to wall heart
Ebstein’s anomaly
DiGeorge syndrome
• Thymic aplasia (T-cell, immune
problems)
• Hypocalcaemia (hypothyroid gland
aplasia, seizures)
• Dysmorphism (unusual facial
appearance)
• Outflow tract abnormalities in the
heart
Tricuspid Atresia
• DiGeorge
syndrome with
low calcium
seen in 1/3 of
the cases