Anatamical and physiological basis of critically ill child

1. ANATOMICAL AND
PHYSIOLOGICAL
BASIS OF
CRITICALLY ILL
INFANT AND CHILD
Presented by: Ms. Deepa krishna

2. • INTRODUCTION:
The pediatric intensive care unit is a place where
the management of the critically ill children takes
place. The children will range from early infancy
to adolescence. There are main anatomical and
physiological differences, which makes the
management a challenging one.

3. Anatomical and Physiological basis of a Newborn.
•Anatomy:
In newborn head is large and neck is short. This produces
the neck flexion. The face and mandible are small. Hence the
orthodontic appliances may be loose.

4.  The relatively large tongue.
 Infants less than 6 months old are obligate nasal
breathers.
 Horse-shaped epiglottis projects posteriorly at 45
degree angle
 The cricoid ring is the narrowest part of the upper
airway.
 The trachea is short and soft.
• Lungs are relatively immature at birth.
• The respiratory movements are mainly
diaphragmatic. The muscles are of type 1.

6.  The ribs are placed more horizontally placed.
 At birth, the two cardiac ventricles are of similar
weight. At birth, right ventricle dominance
occurs.
 The blood volume in the infant is 70-80ml/kg,
which is very less.

7. PHYSIOLOGY:
•The increased respiratory rate in infant is attributed
relatively to greater metabolic rate and oxygen
consumption. Hence it is critically dependant on the
lung surfactant. The lung compliances increases after
one week because of removal of lung fluid.
•The infant has a small stroke volume, ie, 1.5ml/kg at
birth. The cardiac index is highest, 300ml/min/kg.
cardiac index decrease with age upto 70-80ml/min/kg.
•Myocardial response and function will be equivalent to
adult by the age of 2 years.

8. AGE RESPIRATORY RATE
< 1 30 - 40
1-2 25 - 35
2-5 25 - 30
5-12 20 – 25
>12 15 - 20
Repiratory rate by age

9. AGE HEART RATE
<1 110 - 160
1-2 110 – 160
2-5 95 - 140
5-12 80 - 120
>12 60 - 100
Heart rate by age

10. AGE SYSTOLIC BLOOD
PRESSURE
<1 70 - 90
1-2 80 –95
2-5 80 - 100
Systolic blood pressure by age

11. • ASSESSMENT OF SERIOUSLY ILL CHILD:
The important symptoms in seriously ill children,
particularly young infants include drowsiness,
seizure activity, excessive irritability, decreased
activity, difficulty in breathing, cold extremities,
decreased oral intake, decrease in urine output,
apnea or cyanosis and bilious vomiting. Various
clinical scoring systems relying on respiratory effort,
level of activity, color, temperature, playfulness,
quality of cry, reaction to parental stimulation and
hydration status are also available for describing the
severity of illness.

12. RESPIRATORY MONITORING:
•Anatomy and physiology of Respiratory System:
Infants are often vulnerable to infectious particularly
viral infections and other respiratory infection. This is
mainly because of the anatomical peculiarities of children.

13. ANATOMICAL PECULIARITIES:
•In infancy, the thorax is short, with the ribs running more
horizontally. The chest wall is thin, elastic and yielding and
muscles are week.
•The increase in the anterior posterior diameter of the
thorax with inspiration is limited because of horizontally
placed ribs. The infantile larynx is located at higher level
and the glottis is situated at the level of the interspace
between C3 and C4.
•The epiglottis is longer and projects backwards to a greater
degree than in older children.
•The nasal air passages are very important for newborns and
nasal obstruction may result in severe respiratory distress.

14. • The epiglottis rises during swallowing and seals off at the
soft palate, the mouth and the glottis.
• This allows air to pass from the nasal pharynx to the
trachea simultaneously to the swallowing of the milk
already lying in the lateral recess of the hypo-pharynx.
• At birth the lungs are immature. Although the bronchial
tree completes by 16 week of gestation, the number of the
alveoli continues to develop till 8 years.
• Compliance of the child’s lung is more than compared to
adult because of the immature alveolar buds and lack of
elastin.

15. • . Anatomical peculiarities of respiratory tract in children
.
Short thorax
Ribs run horizontally
Thin chest wall
Yielding muscles
Higher level of placement of larynx
Larger epiglottis
Diaphragmatic type of respiration
Newborns obligate nose breathers

16. Anatomical and physiological basis of Bronchial
Asthma:
Spasmodic cough
Dysnea with prolonged expiration
Severe cases child thrush his arm forward.
Chest is hyper reson because of excessive air
trapping.
If the obstruction is severe and persistent, the air
blow decrease markedly.
Breath sounds become soft and feeble.

17. RESPIRATORY FAILURE:
Anatomical and physiological basis:
It can be defined as the inability of the respiratory system
to maintain normal gas exchange. This may be due to lung
failure or pump failure. Its said to occur when the arterial
PCO2 is greater than 50 mm hg and arterial PO2 is less than
50mm hg when breathing air.
Causes of respiratory failure:
∫Pneumothorax
∫Pleural effusion
∫Bacterial and viral pneumonias
∫Atelectasis

18. The course of RF can be divided into 3 pathologic
stages as follows:
exudative,
proliferative, and
 fibrotic.
Pulmonary mechanics
•Involvement is nonhomogeneous, with patchy and
transient airway collapse occurring primarily in dependent
portions of the lung. In these areas, functional residual
capacity (FRC) is reduced.

19. • CARDIOVASCULAR MONITORING:
Anatomical and physiological basis

20. • HEART FAILURE:
Causes Heart Failure in Children?
Overcirculation Failure:
Pump Failure:

21. CNS MONITORING:
Development of the CNS occurs in three stages:
•Cytogenesis
•Histogenesis
•Organogenesis

22. The nervous system is a complex, highly specialized network.
The nervous system controls:
Sight, hearing, taste, smell, and feeling (sensation).
Voluntary and involuntary functions, such as movement,
balance, and coordination.
The ability to think and reason. The nervous system allows
you to be conscious and have thoughts, memories, and
language.
The nervous system is divided into the brain and spinal cord
(central nervous system, or CNS) and the nerve cells that
control voluntary and involuntary movements (
peripheral nervous system, or PNS).

23. Some serious conditions, diseases, and injuries that can cause
nervous system problems include:
Blood supply problems
Injuries (trauma), especially injuries to the head and spinal
cord.
Problems that are present at birth (congenital).
Mental health problems,
Exposure to toxins, such as carbon monoxide, arsenic, or
lead.
Problems that cause a gradual loss of function
(degenerative)
Infections.
Overuse of or withdrawal from prescription and
nonprescription medicines, illegal drugs, or alcohol.

24. The sudden onset of one or more symptoms, such as:
Loss of speech, trouble talking, or trouble understanding
speech.
Numbness, tingling, weakness, or inability to move a part
or all of one side of the body
Dimness, blurring, double vision, or loss of vision in one or
both eyes.
Sudden, severe headache.
Dizziness, unsteadiness, or the inability to stand or walk,
especially if other symptoms are present.
Confusion or a change in level of consciousness or behavior.
Severe nausea or vomiting.

25. ANATOMY AND PHYSIOLOGY OF THE GENITOURINARY SYSTEM

26. KIDNEY FAILURE:
Kidney failure, which is also called renal failure, is
when the kidneys slow down or stop properly
filtering wastes from the body, which can cause
buildups of waste products and toxic substances in
the blood. Kidney failure can be acute (which means
sudden) or chronic (occurring over time and usually
long lasting or permanent).

27. Childhood Kidney Diseases
The most common kidney diseases in children are present at
birth. They include:
•Posterior urethral valve obstruction:
•Fetal hydronephrosis:
•Polycystic kidney disease (PKD):
•Multicystic kidney disease:
•Renal tubular acidosis:
•Wilms tumor:
•Glomerulonephritis:
•Nephrotic syndrome:

28. • GASTRO-INTESTINAL SYSTEM
The gastrointestinal (GI) tract (alimentary canal) is
a continuous tube with two openings, the mouth
and the anus. It includes the mouth, pharynx,
esophagus, stomach, small intestine, and large
intestine.
☻PROCESS OF DIGESTION

29. • PROBLEMS OF NEWBORN GUT:
• Normally, gas is not a problem and causes no pain or
discomfort because it is quickly and easily pushed
through the digestive system. However, babies are born
with a very immature gut. Muscles that support digestion
have not developed the proper rhythm for moving food
efficiently thought the digestive tract. Newborns lack the
benevolent bacterial flora (probiotics) that develop over
time to aid digestion.
• Gas has buoyancy and gas pockets can become trapped in
the upper and lower intestines. The gas acts like a cork,
impeding or halting the flow of gastric juices and built-up
pressure causes painful bloating and swelling of the
abdomen. Baby’s immature digestive system is unable to
cope effectively. When gas pockets form in the stomach,
this can cause the stomach to distend but is also the main
cause of hiccups.

30. The Infant is not an Anatomical Miniature of the Adult
Proportional differences exist between the young infant and the older infant,
child, and adult. These include:
•The oral cavity is small in the newborn and is totally filled by
the tongue due to a small and slightly retracted lower jaw.
•The newborn has a set of sucking pads in the cheeks which
provide stability during sucking.
•The soft palate and epiglottis are in contact at rest, providing
an additional valve at the back of the oral cavity.
•The larynx and hyoid cartilage are higher in the neck and
closer to the base of the epiglottis, providing added protection of
the airway.
•The infants eustachian tube runs horizontally from the middle
ear into the nasopharynx, rather than its later vertical angle in
the older child and adult.

31. IMPLICATIONS FOR THE CHILD WITH
SWALLOWING DYSFUNCTION
•The Absence of a Swallowing Reflex Leaves the Airway
Unprotected
If the swallowing reflex is not triggered by backward
movement of the bolus and/or intention, the airway
remains open and unprotected. The upper esophageal
sphincter remains closed, preventing food entrance into
the esophagus and indirectly biasing its movement into
the open airway.
•Delay in Elicitation of the Swallowing Reflex Places the
Airway in a Risk Position
This creates a risk of aspiration before, during, or after
the swallow has been triggered