Approach to a Neonate with Cyanosis

comprehansive review of approach to neonatal cyanosis

1. Dr.Afnan Shamraiz

2. Contents
Introduction
Central, Peripheral and Differential
cyanosis
Mechanism
Etiology
Approach
Principles of Treatment
Conclusion

3. Introduction
Cyanosis is derived from the colour ‘cyan’, which
comes from ‘kyanous’, the Greek word for blue
It is defined as the bluish discoloration of the skin
and the mucous membranes, resulting from an
increase in the reduced Haemoglobin or of
haemoglobin derivatives in the small vessels of
those areas.
Bluish discoloration of the tissues that results when the
absolute level of reduced hemoglobin in the capillary
bed exceeds 3- 4 g/dL
Depends upon the total amount of reduced
hemoglobin rather than the ratio of reduced to
oxygenated hemoglobin.

4. Sites to detect cyanosis
Lips
Nail beds
Ears
Malar Prominences
Palms and Soles
Tongue
Mucous membranes of gum,soft palate,cheeks

5. Types of Cyanosis
Central Cyanosis
Peripheral Cyanosis
Mixed Cyanosis
Other Types
Enterogenous/Pigment Cyanosis
Differential Cyanosis
Acrocyanosis
Orthocyanosis

6. Central cyanosis
Pathologic condition
caused by reduced arterial
oxygen saturation.
Involves highly vascularized
tissues, such as the lips
and mucous membranes,
through which blood flow is
brisk and the arteriovenous
difference is minimal.
Cardiac output typically is
normal, and patients have
warm extremities.

7. Mechanism
Decreased arterial oxygen saturation due to
marked decrease in oxygen tension in the
arterial blood(arterial PaO2 is reduced)
Sites-
Tongue (margins & undersurface)
Inner aspect of lips
Mucous membranes of gums,soft palate,cheeks

8. Peripheral cyanosis
Causes-
○vasomotor instability,
vasoconstriction caused by
exposure to cold, venous
obstruction, elevated venous
pressure, polycythemia, and
low cardiac output,
Affects the distal
extremities and circumoral
or periorbital areas .

9. Mechanism
Normal systemic arterial oxygen saturation and
increased oxygen extraction, resulting in a wide
systemic arteriovenous oxygen difference
The increased extraction of oxygen results from
sluggish movement of blood through the
capillary circulation
•Sites
•Tip of nose
•Ear lobules
•Outer aspect of lips,chin,cheek
•Tips and nailbeds of fingers,toes
•Palms,soles

10. Mixed Cyanosis
Cardiogenic shock+ pulmonary oedema
CCF due to lt.sided heart failure
Polycthemia (rare)
Orthocyanosis
Present in upright position due to hypoxia
occuring in erect posture in Pulmonary
Arteriovenous Malformation

11. Enterogenous/pigment cyanosis
Due to presence of excessive –
sulphaemoglobin(>0.5g/dl),methaemoglobin(
>1.5g/dl
Causes
 Hereditary haemoglobin M disease
Poisoning by aniline dyes
Drugs-
nitratres,nitrites,phenacetin,sulphonamides
Carboxyhaemoglobinaemia

12. Differential Cyanosis
Hands red (less blue) and feet blue seen in PDA with
reversal of shunt (Differential Cyanosis) Requires
pulmonary vascular resistance elevated to a systemic
level and a patent ductus arteriosus
L R shunt
Pulmonary
hypertension
R to L
Reversal
of shunt
Desaturated blood from the ductus
enters the aorta distal to the left
subclavian artery, sparing the
brachiocephalic circulation.

13. Reverse Differential Cyanosis
Hands blue and feet red seen in
Coarctation of Aorta with TGA(Reverse
Differential Cyanosis
Intermittent Cyanosis seen in Ebstein’s
Anomaly

14. Central Vs Peripheral Cyanosis
SITES TONGUE,ORAL CAVITY TONGUE UNAFFECTED
HANDSHAKE FEELS WARM FEELS COLD
APPLICATION OF
WARMTH,COLD
NO CHANGE WARMTH-CYANOSIS
INCR,COLD-
DECREASES
APPLICATION PURE O2 MAY IMPROVE NO RESPONSE
CLUBBING,POLYCYTHA
EMIA
USUALLY PRESENT ABSENT
PULSE VOLUME MAYBE HIGH LOW VOL
DYSPNOEA PT BREATHLESS NO RESPIRATORY
PROBLEM

15. Acrocyanosis
Condition in which there is arterial
vasoconstriction,and secondary dilation
of capillaries and venules with resulting
persistant cyanosis of the hands and
less fequently the feet.
part of normal transition
may last 72hr
beware APGAR of 10
○hypoperfused
○severe anemia

16. Psuedocyanosis
Bluish tinge to the skin and or mucous
membranes that is not associated with
either Hyoxemia or Peripheral
Vasoconstriction
Metals
Drugs

17. Factors altering cyanosis
Colour of the cutaneous pigment
Thickness of the skin
State of cutaneous capillaries
Cyanosis becomes apparent when the
concenteration of the reduced haemoglobin in
capillary blood vessels exceeds 40 g/l or 4g/dl

18. Factors affecting the detection of
cyanosis in the newborn
Hemoglobin concentration -
Detected at higher levels of saturation in
polycythemic than in anemic patients.
Significant oxygen desaturation can be present
in an anemic patient without clinically detectable
cyanosis.
As an example, 3 g/dL of reduced hemoglobin is
associated with an oxygen saturation of 67
percent when the total hemoglobin
concentration is 9 g/dL, and 85 percent when
the hemoglobin concentration is 20 g/dL.

19. The arterial oxygen saturation level at which cyanosis is
detectable at different total hemoglobin concentrations is
illustrated above. The solid red portion of each bar represents 3
gm/dL reduced hemoglobin.

20. Factors affecting the detection of
cyanosis in the newborn
Fetal hemoglobin —
Binds oxygen more avidly than adult hemoglobin.
The oxygen dissociation curve is shifted to the left, so
that for a given level of oxygen tension (PO2), the
oxygen saturation (SO2) is higher in the newborn than
older infants or adults
It also follows that for a given level of oxygen
saturation, the PO2 is lower in newborns.
As a result, cyanosis is detected at a lower PO2 in
newborns compared with older patients. Thus, in
evaluating a cyanotic newborn, PO2 should be
measured in addition to SO2 to provide more
complete data.

21. Factors affecting the detection of
cyanosis in the newborn
Other physiologic factors common in
sick newborns affect the oxygen
dissociation curve.
Those that increase the affinity of
hemoglobin for oxygen (shifting the
oxygen dissociation curve to the left),
decrease the concentration of reduced
hemoglobin at a given arterial P02, and
lower the PO2 at which cyanosis first
appears.

22. These factors
include alkalosis,
hyperventilation (low
PC02), cold
temperature, and
low levels of 2,3
diphosphoglycerate
For fetal hemoglobin, the normal curve
(a) is shifted to the left (b)

23. Cyanosis
0
10
20
30
40
50
60
70
80
90
100
0 20 40 60 80
HCT
%

S
a
t
u
r
a
t
i
o
n
Cyanosis…
Cyanosis is
dependent on HCT
and % Sat
Florescent light
makes cyanosis
hard to see.
Except in the
extreme, cyanosis
is not obvious
Any question,
check a pulse ox

24. In contrast, acidosis,
fever, or increased
adult hemoglobin shift
the curve to the right.
As a result, at a given
arterial PO2, there is
increased oxygen
delivery to the tissues
resulting in a greater
concentration of
reduced hemoglobin,
and cyanosis appears
more readily.
For fetal hemoglobin, the normal curve
(a) is shifted to the left (b)

25. Factors affecting the detection of
cyanosis in the newborn
Skin pigmentation -
Less apparent in the skin of patients with
darker pigmentation.
Examination should include the nail beds,
tongue, and mucous membranes, which are
less affected by pigmentation.

27. Etiology Can be divided in to,,
Site of cynosis
Central causes
Peripheral causes
Mecanism of
cynosis
Alveolar hypoventilation
Diffusion impairment
Ventilation-perfusion
mismatch
Right-to-left shunting at the
intracardiac, great vessel,
or intrapulmonary level
Hemoglobinopathy
(including
methemoglobinemia) that
limits oxygen transport

28. Central Cyanosis:-
Decreased arterial oxygen saturation
Decreased atmospheric pressure-High altitude
Impaired pulmonary function
Alveolar hypoventilation
Pulmonary ventilation perfusion imbalance
Impaired oxygen diffusion
Anatomic Shunts –ASD,VSD,PDA
Congenital Heart Diseases-Fallots Tetrology,TGA
Pulmonary AV fistulas
Mutiple small intrapulmonary shunts
Haemoglobin Abnormalities

29. Peripheral Cyanosis
Decreased Cardiac Output
Cold Exposure
Redistribution Of blood from extremities
Arterial Obstruction-embolus,raynauds
phenomenon
Venous Obstruction-thrombophlebitis,SVC
syndrome
Frost bite
CCF,shock,Peripheral Circulatory Failure
Hyperviscosity -Multiple myeloma,Polycythemia
Peripheral Vascular Diseases-
atherosclerosis,buerger’s
Mitral Stenosis
Cryoglobulinemia

30. Non- cardiac causes
Alveolar hypoventilation
Central nervous system depression:
asphyxia, maternal sedation, intraventricular
hemorrhage, seizure, meningitis,
encephalitis
Neuromuscular disease: Werdnig-Hoffman
disease, neonatal myasthenia gravis,
phrenic nerve injury
Airway obstruction: choanal atresia,
laryngotracheomalacia, macroglossia, Pierre
Robin syndrome

31. Non- cardiac causes
Ventilation/perfusion mismatch
Airway disease: pneumonia, aspiration, cystic
adenomatoid malformation, diaphragmatic
hernia, pulmonary hypoplasia, labor
emphysema, atelectasis, pulmonary
hemorrhage, hyaline membrane disease,
transient tachypnea of the newborn
Extrinsic compression of lungs: pneumothorax,
pleural effusion, chylothorax, hemothorax,
thoracic dystrophy

32. Non-cardiac causes
Hemoglobinopathy
Methemoglobinemia: congenital or secondary to
toxic exposure
Other hemoglobinopathies
Diffusion impairment
Pulmonary edema: left-sided obstructive cardiac
disease, cardiomyopathy
Pulmonary fibrosis
Congenital lymphangiectasia

33. Cardiac causes
Decreased pulmonary blood flow-
Tetralogy of Fallot
Tricuspid valve anomaly
Pulmonary valve atresia
Critical valvular pulmonary steanosis
Increased pulmonary blood flow-
Transposition of great arteries
Truncus arteriosus
Total anomalous pulmonary venous connection

34. Cardiac causes
Severe heart failure-
Hypoplastic left heart syndrome
Coarctation of the aorta
Interrupted aortic arch
Critical valvular aortic steanosis

35. The 6 T’s
Total Anomalous Pulmonary Veins
Tetrology of Fallot
Tricuspid Atresia
Transposition
Truncus Arteriosus
Total AcardiaTotal Acardia

36. Mnemonic
A 7T" is often added for "tons" of other diseases,
such as double outlet right ventricle, pulmonary
atresia, multiple variations of single ventricle,
hypoplastic left heart syndrome, or anomalous
systemic venous connection (left superior vena
cava connected to the left atrium

37. Differential cyanosis
With normally related great arteries, oxygen
saturation may be higher in the upper than
lower extremity in patients if there is right-to-
left shunting through the ductus arteriosus.
Seen with severe coarctation or interrupted
aortic arch.
May also occur in patients persistent
pulmonary hypertension of the newborn
The differential effect is reduced if there is also
right-to-left shunting at the level of the foramen
ovale, or if there is left-to-right shunting across
a coexisting ventricular septal defect

38. Differential cyanosis
Reversed differential cyanosis is a rare
finding that may occur in patients with
transposition of the great arteries
associated with either coarctation or
pulmonary hypertension.
In these infants, oxygen saturation is
higher in the lower than upper extremity.

40. Aim
Differentiate physiologic from pathologic
cyanosis
Differentiate cardiac from non- cardiac
cause of cyanosis
Find cause which needs urgent
treatment or referral

41. Not so serious
Acrocyanosis
Bluish color in the hands and feet and around
the mouth (circumoral cyanosis). The mucus
membranes generally remain pink.
Reflects benign vasomotor changes in the
diffuse venous structures in the affected areas.
Does not indicate pathology unless cardiac
output is extremely low, resulting in cutaneous
vasoconstriction
Cyanosis soon after birth- transition from
intrauterine to extrauterine life
Hand or leg prolapse

42. Perinatal history
Drug intake
Causing neonatal depression
Lithium- Ebstein anomaly
Phenytoin- PS and AS Fetal hydantoin synd-
Fetal alcohol- VSD,ASD
Maternal diabetes-
TGA, ventricular septal defect (VSD), and hypertrophic
cardiomyopathy
Connective tissue disorder- Heart blocks associated with
anti-Ro/SSA and anti-La/SSB antibodies.
Congenital intrauterine infections cytomegalovirus,
herpesvirus, rubella, or coxsackie virus can lead to cardiac
structural abnormalities or functional impairment
Antenatal fetal echocardiography

43. History
Methemoglobinemia may be acquired
following exposure to aniline dyes,
nitrobenzene, nitrites, and nitrates.
Advanced maternal age Trisomy 21
associated with many congenital heart
defects (cyanotic and acyanotic)
Oligohydramnios …..Pulmonary
hypoplasia

44. Onset of cyanosis in cardiac lesions-
Depends on-
Nature and severity of the anatomic defect
In utero effects of the structural lesion
Alterations in cardiovascular physiology secondary
to the effects of transitional circulation like closure of
ductus arteriosus and the fall in pulmonary vascular
resistance
A ductal dependent lesion is one that depends on the ductus to get
adequate blood flow to the pulmonary and systemic circuits, or provide
mixing
○PS
○CoA
○TGA

45. Labour Hx Associated causes of cyanosis
•PROM, fever, GBS +ve •Sepsis
•Sedatives/anesthetics •Respiratory depression, apnea
•C-section •TTN, PPHN
•Preterm infant •RDS
•Meconium •MAS (pneumonia)

46. Onset of cyanosis in cardiac lesions
Age on admission In order of frequency
0-6 days D- transposition of great arteries
Hypoplastic left ventricles
Tetralogy of fallot
7-13 days Coarctation of aorta
Hypoplastic left ventricle
D-transposition of great arteries
Tetralogy of fallot
14-28 days Coarctation of aorta
Tetralogy of fallot
D- transposition of great arteries
Neonatology- Pathophysiology and management of newborn, 5
th
edition ed.
1999. Philadelphia; Lippincott Williams and Wilkins

47. History- Risk factors
Pneumonia/ sepsis-
PROM
Foul smelling liquor
Maternal pyrexia
Maternal GBS
TTN –
Birth by cesarean section
with or without labor
Male sex
Family history of asthma
(especially in mother)
Macrosomia
Maternal diabetes
Polycythemia-
small-for-gestational age
MAS-
Post maturity
Small for gestational age
Placental dysfunction
Fetal distress
Meconium stained liquor
Pneumothorax-
Aggressive resucitation
IPPV
Meconiun aspiration
HMD
Hypoplastic lung
Staph pneumonia
Hyaline membrane
disease-
Premature infant
Infant of diabetic mother

48. History
Choanal atresia-
Cyanosis decreases during crying
Confirmed by failure to pass a soft No. 5F to
8F catheter through each nostril

49. Physical Examination
Vital signs-
Hypothermia or hyperthermia- infection.
Tachycardia-hypovolemia.
Weak pulses- Hypoplastic left heart
syndrome or hypovolemia.
Pulses or blood pressures stronger in
the upper than in the lower extremities-
coarctation of the aorta.

50. Physical Examination
Congenital heart disease-
Respirations often are unlabored unless there is
pulmonary congestion or complicated by the
development of heart failure or acidosis, which
will affect the respiratory pattern.
CVS-
Presence or absence of a heart murmur is of little
assistance. Loud S2 suggests pulmonary or
systemic hypertension or malposition of the aorta.
several of the most serious anatomic
abnormalities, such as transposition of the
great arteries, produce only a very soft
murmur or no murmur at all

51. Physical Examination
Inspiratory stridor-
upper airway obstruction
Chest-
Asymmetric chest movement combined with
severe distress-
○alarming sign for tension pneumothorax,
diaphragmatic hernia
Transillumination of the chest-
○Pneumothorax on an emergent basis

52. Physical Examination
P/A-
Scaphoid abdomen
○Congenital diaphragmatic hernia
Hepatosplenomegaly-
○congestive heart failure, maternal diabetes,
or congenital infection.

53. Physical Examination
Central nervous depression-
Causes shallow, irregular respirations and
periods of apnea.
Affected infants typically appear hypotonic
and lethargic.

54. Investigations
CBC & diff :
Increase or decrease WBC : sepsis
Hematocrit > 65% : polycythemia
Serum glucose:
to detect hypoglycemia
Arterial Blood Gases (ABGs):
Arterial PO2: to confirm central cyanosis : SaO2 not as
good an indicator due to Increase fetal Hb affinity for O2
(left-shift)
Increase PaCO2: may indicate pulmonary or CNS
disorders, heart failure
Decrease pH: sepsis, circulatory shock, severe hypoxemia
Methemoglobinemia: Decrease SaO2, normal PaO2,
chocolate-brown blood

55. If central cause- appropriate scan and
drug levels
Hb electropheresis…..Hb M
Decrease pH: sepsis, circulatory shock,
severe hypoxemia
Decrease pH: sepsis, circulatory shock,
severe hypoxemia
Sepsis screening

56. Pulse oximetry screening
Difficulty in visual detection of cyanosis
Potentially severe consequences of
missing an early sign of CHD
“5
th
vital sign”
Sensitivity and specificity varies-
Criteria used for abnormal test
Timing of screening
Probe site
Quality of the equipment
Signal quality and neonate behaviour
Health care workers expertise
Signal quality and infant behavior — Measurements should not be
performed when the infant is crying or moving as it reduces the quality of the
signal and the accuracy of the test.

57. Oxygen saturation should be performed
initially on room air to serve as a
baseline.
Subsequently can be served to
differentiate between cardiogenic and
non-cardiogenic causes

58. Terms
PaO
2
Arterial Oxygen Pressure
Measured on an ABG machine
Oxygen dissolved in plasma
○0.003 ml O
2
/mmHg/dl plasma
SaO
2
Percent Oxygen Saturation
Measured by saturation monitor (pulse-Ox)
~1.34ml O2/g Hb

59. Hyperoxia test
If a low-pulse oximeter reading persists, it
may be appropriate to proceed to a
hyperoxia test. It is indicated if the pulse
oximeter reading is less than 85% in both
room air and 100% oxygen

Useful in distinguishing cardiac from
pulmonary causes of cyanosis.

60. Hyperoxia test
Arterial oxygen tension is measured in the
right radial artery (preductal) and in a lower
extremity artery while the patient breathes
100 percent oxygen (postductal).

61. Hyperoxia Test
Infant on Room Air, get ABG
Infant on 100% oxygen, get ABG
PaO
2
unchanged = fixed shunt = CCHD
Max PaO
2
<100 = CCHD
Max PaO
2
>200 = No CCHD

62. Hyperoxia test
Disease Result- Increase
in PaO
2
Lung disease is more likely than
CHD
>150 mmHg
TGA or severe pulmonary outflow
obstruction
<50 to 60 mmHg
In lesions with intracardiac mixing
and increased pulmonary blood
flow such as truncus arteriosus-
>75 to 150
mmHg

63. Differential cyanosis
To detect differential cyanosis, oxygen
saturation should be measured in sites
that receive blood flow from both
preductal (right hand) and postductal
(foot) vessels. It is preferable to use the
right (rather than left) upper extremity,
since the left subclavian artery arises
close to the ductus arteriosus, and some
of its flow may come from the ductus
and thus not reflect preductal values

64. Chest X-Ray
To identify pulmonary causes of cyanosis:
pneumothorax, pulmonary hypoplasia, diaphragmatic
hernia, pulmonary edema, pleural effusion, etc.
Useful in evaluating congenital heart disease: e.g.,
cardiomegaly & vascular congestion: heart failure
Aberrancy of the cardiothymic silhouette-
Suggest the presence of structural heart disease,
and
Abnormalities of the lung fields may be helpful in
distinguishing a primary pulmonary problem such as
meconium aspiration

65. Chest X- Ray
Pulmonary vascular markings-
Decreased in CHD with obstructed
pulmonary blood flow such as tetralogy of
Fallot, severe pulmonary stenosis or atresia,
and tricuspid atresia.
Increased in admixture lesions like
transposition of the great arteries, total
anomalous pulmonary venous connection,
and truncus arteriosus.

66. Total Anomalous Pulmonary Venous
Return
Snowman

67. Tetralogy of Fallot
Boot
shape

68. Transposition of Great Arteries
Egg on a
string

69. Echocardiography
Indicated if abnormal cardiac
examination suggestive of congenital
heart defect, failed hyperoxia test
(cardiac disease suspected) or has
unclear diagnosis

70. Treatment
Goals-
Provide adequate tissue oxygen and CO2
removal
Principles-
Establish airway
Ensure oxygenation
Ensure adequate ventilation
Correct metabolic abnormalities
Alleviate the cause of respiratory distress

71. Monitor Airway, breathing, circulation (ABCs) with
respiratory compromise, establish an airway & provide
supportive therapy (e.g., oxygen, mechanical ventilation)
Monitor Vital signs
Establish vascular access for sampling blood &
administering meds (if needed): umbilical vessels
convenient for placement of intravenous & intraarterial
catheters
If sepsis is suspected or another specific cause is not
identified, start on broad spectrum antibiotics (e.g.,
ampicillin and gentamycin) after obtaining a CBC, urinalysis,
blood & urine cultures (if possible). Left untreated, sepsis
may lead to pulmonary disease & left ventricular dysfunction.
.

72. An infant who fails the hyperoxia test & does
not have PPHN or a CXR showing pulmonary
disease likely has a congenital heart defect
that’s ductus-dependent. If cardiac disease is
suspected, immediately start PGE1 infusion.
Complications of PGE1 infusion include
hypotension, tachycardia, apnea. Secure a
separate intravenous catheter to provide fluids
for resuscitation and ensure accessibility of
intubation equipment should they be required

73. Treatment-
Prostaglandin E1
For ductal dependant CHD/ reduced
pulmonary blood flow- Fail hyperoxia
test( An arterial PO2 of less than 100 torr in
the absence of clear- cut lung disease)
Infusion of prostaglandin E1 at a dose of
0.05- 0.1mcg/kg/min intravenously to
maintain patency

74. Treatment-
Prostaglandin E1-
S/E- hypoventilation, apnea, edema and low
grade fever
Benefits- Can be stabilized more easily,
allowing for safe transport to a tertiary care
center. More time is also available for
thorough diagnostic evaluation and patients
can be brought to surgery in a more stable
condition.

75. Conclusion
Identify those that are life-threatening.
complete maternal and newborn history
perform a thorough physical examination
recognize the common respiratory and
cardiac disorders
differentiate among various diagnostic
entities
For ductal dependent lesion, start
prostaglandin E1 and early referral

76. References
Nelson textbook of pediatrics
Cloherty manual of neonatal care
Approach To Cyanotic Heart Disease In The First
Month Of Life , Harry J. D'Agostino, Jr., M.D. and
Eric L. Ceithaml, M.D.
Pediatrics in Review. 1999;20:350-352.)
© 1999, Consultation with the Specialist,
Nonrespiratory Cyanosis, Jon Tingelstad, MD
UpToDate