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Anatomy and Physiology 1111 > Module 17 > Flashcards

Module 17 Flashcards

1
Q

Functions of the Respiratory System

A
  • Provides for gas exchange: brings O2 into body, excreted CO2 from body
  • Helps regulate blood pH
  • Contains smell receptors
  • Filters incoming air
  • Produces vocal sounds
  • Excretes water and heat
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2
Q

What are the 4 Process of the Respiratory System?

A
  1. Pulmonary Ventilation: moving air into and out of the lungs
  2. External Respiration: exchange of gases at the alveoli of the lungs
  3. Transport of Respiratory Gases: to the tissues
  4. Internal Respiration: exchange of gases between blood and tissue
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3
Q

Function of the Nose and Paranasal Sinusus

A

As air enters the respiratory system, nose hairs filter larger particles.

Scroll-like bones make up the nasal conchae which are lined by a mucous membrane.

  • Air is moisturized, warmed, and filtered by turbulence inside nasal passages.
  • Increased surface area and mixing of air enhances olfaction

Air Spaces are also much lighter than bone, so head is not too heavy.

Sinuses were designed to drain from an animal on all fours. Walking on two legs causes sinus problems.
- mucus and microorganisms can pool in the inferior part of sinuses and does not drain, leading to chronic infections and inflammation.

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4
Q

Function of the Pharynx

A

The pharynx is a passageway for air, liquids, and solids. The Pharynx is divided into three zones:

  1. Nasopharynx: Lies behind the internal nares and has a purely respiratory function. Houses eustacian tubes and pharyngeal tonsils (adenoids).
  2. Oropharynx: Lies behind the mouth with boh respiratory and digestive functions. Houses palatine tonsils
  3. Laryngopharynx: Lies inferior to the oropharynx and opens into the larynx and esophagus. Respiratory and digestive functions
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5
Q

Function of the Larynx

A

The larynx (voice box) is the structure that gives the laryngopharynx its name. It connects the larygopharynx with the trachea. It is located just inferior to the hyoid bone and epiglottis.

epiglottis: “sorting paddle” that detects and responds to material entering the oropharynx. If a liquid or solid, it is sorted into the esophagus. If gas, it is allowed into larynx and trachea (initial segment of respiratory system).

Sound: produced by vibrations as air passes the vocal chords.

  • Volume controlled by pressure
  • Pitch caused by tension on vocal chords
  • Men have lower voices because of the effects of androgens during puberty thickening and elongating vocal chords.
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6
Q

What are the 9 Pieces of Cartilage that Make up the Larynx?

A

Single Cartilage:

  1. Thyroid (Adam’s apple)
  2. Epiglottis
  3. Cricoid
  4. Glottis
  5. Hyoid Bone

Paired Cartilage:

  1. Arytenoid
  2. Corniculate
  3. Cuniform
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7
Q

Thyroid (Adam’s Apple)

A

A cartilage that makes up part of the larynx

Forms the anterior surface of the larynx/

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8
Q

Epiglottis

A

A cartilage that makes up part if the larynx

Leaf shaped piece of hyaline cartilage that closes over the larynx when food or liquids are swallowed. The epiglottis allows gases such as oxygen through the larynx into the trachea

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9
Q

Cricoid

A

A cartilage that makes up part if the larynx

A ring of hyaline cartilage that forms the interior portion of the larynx.

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10
Q

Arytenoid

A

A cartilage that makes up part if the larynx

Influence changes in position and tension of the vocal folds

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11
Q

Corniculate and Cuneiform

A

Cartilage that makes up part if the larynx

Support the vocal folds and the epiglottis

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12
Q

Glottis

A

A cartilage that makes up part of the larynx

opening of the larynx. Includes vocal chords and opening between chords.

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13
Q

Hyoid Bone

A

A cartilage that makes up part of the larynx

floating, U-shaped bone in anterior neck

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14
Q

Tracheotomy

A

If we need to establish an emergency airway, and the oropharynx is blocked and/or traumatized, the best place to do a tracheotomy is between the thyroid and the cricoid cartilages.
- This is also the site of attachment for a permanent tracheostomy (e.g. in oral cancer)

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15
Q

Trachea

A

The trachea, or windpipe, is a semi-rigid tube about 12 cm long x 2.5 cm in diameter.

  • Contains 16-20 C-shaped rings of cartilage giving it support and preventing collapse of the trachea, expecially during inhalation.
  • Posterior surface is shared with the esophagus
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16
Q

Bronchi

A

The trachea divides into the right and left primary bronchi at the carina.

  • the primary bronchi divide into two or three secondary bronchi, then teritary bronchi, and so forth.
  • The right pulmonary bronchus extends more vertically, is wider, and shorter than the left. Because of this, an aspirated object is more likely to lodge in the right bronchus than the left.
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17
Q

The Lungs and Bronchi

A

One primary bronchus for each lung (right and left. One secondary bronchus for each lobe of the lung:

  • R lung: 3 lobes
  • L lung: 2 lobes

Bronchi enter at the hilus along with blood vessels. The superior part of the lung is the apex (extends above the clavicle). The inferior part of the lung is the base (rests on diaphragm).

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18
Q

Pleural Membranes

A

Like other viscera, lungs are covered with a double-walled membrane.

  • the visceral pleura adheres to the lung
  • the parietal pleura adheres to the chest wall
  • there is a thin layer of pleural fluid between these, in the pleural cavity.
  • Tight contact between these membranes (with liquid seal and lubrication) is critical for lung function.
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19
Q

Ribs and Thoracic Wall

A

The visceral organs of the thoracic cavity are protected by the ribs and sternum. The volume of the thoracic cavity changes due to contractions of muscles expanding this area.

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20
Q

Diaphragm and Intracostal Muscles

A

The inferior portion of the lungs rest on a large, dome-shaped muscle, the diaphragm. This muscle, which forms the floor of the thoracic cavity, is the most important muscle that powers breathing.
- Contraction of this muscle enlarges the thoracic cavity enabling inhalation. The diaphragm is responsible for about 75% of the air that enters the lungs during normal quiet breathing.

The internal intercostal muscle make up the intermediate layer of the intercostal space. These muscle help decrease the size of the thoracic cavity during forced exhalation.

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21
Q

Phrenic Nerve

A

The phrenic nerve originates from spinal cord at levels C3, C4, and C5 (mnemonic: “C3,4, and 5 keep the diaphragm alive”)

  • Phrenic nerve distributes over the superior surface of the diaphragm
  • When stimulated, causes contraction of the diaphragm muscle.
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22
Q

Sympathetics: Pulmonary Plexus

A

The lung receives both sympathetic and parasympathetic innervation. Sympathetic (norepinephrine) causes dilation of bronchial smooth muscle.

  • Preganglionic cell bodies in intermediate horn of T1-T4 spinal cord
  • Postganglionic cell bodies in sympathetic chain ganglia
  • Nerves form pulmonary plexus in hilus of lung.
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23
Q

Parasympathetics: Pulmonary Plexus

A

Parasympathetic innervation via vagus nerve (CN X)

  • Acetylcholine is neurotransmitter released
  • Causes mucus secretion and constriction of bronchial smooth muslce.
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24
Q

Conduction Zone vs. Respiratory Zone

A

The Conducting Zone is that part of the respiratory system that brings air into or out of the lungs

The Respiratory Zone is that part of the respiratory system where gas exchange takes place

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25
Q

Upper and Lower Respiratory Tract

A

The upper respiratory tract includes the nasal cavity, oral cavity, and all three divisions of the pharynx, and larynx.

The lower respiratory tract includes the trachea and lungs (bronchi, bronchioles, and alveoli)

Functional importance: upper respiratory tract is full of microorganisms, but lower respiratory tract is (theoretically) sterile.

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26
Q

Air Molecule Itinerary

A
  1. Outside World
  2. Mouth or Nose
  3. Pharynx
  4. Larynx
  5. Trachea
  6. Left or right primary bronchus
  7. Secondary bronchus
  8. Tertiary bronchus
  9. Bronchiole
  10. Terminal bronchiole
  11. Respiratory bronchiole
  12. Alveoli
  13. Bloodstream
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27
Q

Epithelium of Trachea and Bronchi.

A

Epithelium of trachea and bronchi is pseudostratified columnar epithelium. (cilia, and mucus-secreting goblet cells)

Mucus + cilia form mucociliary escalator which brings dust and other particles out of the lungs and into the pharynx to be swallowed.

The trachea is epithelial lining supported by rings of hyaline cartilage. The esophagus is a muscular tube just posterior to the trachea

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28
Q

Bronchi Histology

A

Bronchi and bronchioles are ringed by smooth muscle. This smooth muscle regulates the diameter of of the conducting airways.

  • Sympathetic = fight-or-flight = increase airway diameter
  • Parasympathetic = decrease airway diameter, increases secretions. (this also occurs in inflammation - ex. asthma)
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29
Q

Bronchiole Histology

A

As respiratory bronchioles expand to form alveoli, histology changes.

  • Here, gas exchange will take place, so cells and structure support this function
  • Type I alveolar cells are simple squamous epithelium that form a thin alveolar-capillary (A-C) membrane in collaboration with capillary endothelial cells. These cells are the site of gas exchange and by far the most numerous cell lining the alveoli.
  • Type II alveolar cells (septal cells) and simple cuboidal epithelium that secrete surfactant. This is a soap-like substance that decreases surface tension allowing easier inflation of the alvoli and preventing the collapse of alveoli after exhalation.
  • Alveolar macrophages engulf large particles and invaders, then “ride” the mucociliary escalator out of the lung.
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30
Q

Respiration

A

The process of gas exchange in the body

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31
Q

Pulmonary Ventilation

A

The inhalation and exhalation of air. This involves the exchange of air between the atmosphere and the alveoli of the lungs.

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32
Q

Inhalation

A

Movement of air into the lungs from the atmosphere. An active process requiring muscle action.

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33
Q

Exhalation

A

Movement of air out of the lungs into the atmosphere.

  • A passive process during quiet breathing due to the elastic recoil of the lungs
  • An active process (muscle help) during vigorous exercise or certain disease conditions causing difficult expiration (chronic obstructive pulmonary diseases).
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34
Q

The Kinetic Molecular Theory

A

Gases consist of molecules that are free to bounce around. - - The collision of these molecules with the wall of a container is known as pressure.
- The speed at which the molecules move is temperature

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35
Q

Measuring Pressure

A

Pressure is measured in atmospheres: the pressure exerted by the atmosphere at sea level

Also measured in millimeters of mercury (mm Hg): this describes how high a column of mercury is raised by gas pressure. 1 atm = 760 mm Hg

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36
Q

Where Does Pressure Come From?

A
  • Pressure come from collisions between the molecules and the walls of the container
  • Higher temperature = more collisions = higher pressure
  • More molecules = more collisions = higher pressure
  • Small container = more collisions = higher pressure
37
Q

What are the 5 Principles of the Kinetic Molecular Theory?

A
  1. There is a lot more space between gas particles than the gas particles themselves occupy
  2. Particles move in a straight line until they collide. They move in different directions and have different speeds.
  3. The particles in a gas don’t interact with each other much, if at all.
  4. When particles collide, all the energy goes into bouncing, and none is absorbed by the particle
  5. The average speed of the particles is related to the temperature.
38
Q

Boyle’s Law

A

Boyle’s Law says that pressure (the number of collisions with the walls of a container) times volume is a constant at constant temperature. Human bodies are at a constant temperature of 37 degrees C.
- Pressure and volume are inversely related. If one goes up, the other goes down.

P1V1 = P2V2

39
Q

Movements During Breathing

A

Boyle’s Law has direct application to the principles governing inspiration and expiration.

Muscles produce two movements in chest:

  • “pump handle” action of sternum
  • “bucket handle” action of ribs
  • During inspiration, the diaphragm, internal intercostal muscles and external intercostal muscles all contract. These movements increase the volume of the thoracic cavity.
  • So, if volume goes up, pressure goes down.
40
Q

Pneumothorax

A

If air can leak into the pleural cavity, then thoracic cavity cannot develop a pressure difference.

  • No pressure difference and surface tension (even with surfactant) takes over and causes the delicate alveolar-capillary membrane to collapse in on itself.
  • When this happens all over the lung, the entire lung collapses and pneumothorax results.
  • This is a special case of the more general term atelectasis, any abnormal structure in the alveoli of the lung.
41
Q

What are the 4 Respiratory Volumes?

A

Pulmonary function can be tested using a spirometer, which measures the volume of air exchanged during breathing and the respiratory rate.

  1. Tidal Volume (VT)
  2. Inspiratory Reserve Volume
  3. Expiratory Reserve Volume
  4. Residual Volume
42
Q

Tidal Volume (VT)

A

A type of Respiratory Volume

The volume of air inspired or expired during normal quiet breathing

43
Q

Inspiratory Reserve Volume

A

A type of Respiratory Volume

All of the air that you can breathe in from the top of tidal volume (during a very deep inhalation)

44
Q

Expiratory Reserve Volume

A

A type of Respiratory Volume

All of the air that you can breathe out from the bottom of tidal volume during a forced exhalation.

45
Q

Residual Volume

A

Air still present in lung tissue after the thoracic cavity has been opened.

46
Q

What are the 4 Respiratory Capacities?

A

Respiratory capacities are combinations of specific lung volumes:

  1. Inspiratory Capacity
  2. Functional residual capacity
  3. Vital capacity
  4. Total lung capacity
47
Q

Inspiratory Capacity

A

A type of Respiratory Capacity

The sum of tidal volume and inspiratory reserve volume

48
Q

Functional Residual Capacity

A

A type of Respiratory Capacity

The sum of residual volume and expiratory reserve volume

49
Q

Vital Capacity

A

A type of Respiratory Capacity

The sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume

50
Q

Total Lung Capacity

A

A type of Respiratory Capacity

The sum of vital capacity and residual volume

51
Q

Dalton’s Law

A

The exchange of gases at the alveoli and the tissues is explained by 2 physical laws: Dalton’s Law and Henry’s Law.

Dalton’s Law says that the particles in a gas don’t care about each other, basically ignore eachother.

  • Each contributes to a little bit of pressure
  • Therefore, the total pressure is the sum of pressures coming from each gas: This is called the sum of partial pressures.

PA Total = PA+PB+PC+PD….

52
Q

Henry’s Law

A

Henry’s Law says the amount of a gas that is dissolved in a liquid is directly proportional to the partial pressure of the gas. For example, carbonated drink:

  • CO2 gas in the space above surface of liquid is in equilibrium with the CO2 gas dissolved in the soda.
  • When you uncap it, the CO2 in the solution is released into the air (partial pressure of CO2 in air is almost zero)
  • Soda goes flat
53
Q

High-Altitude Physiology

A

Lack of oxygen at high altitude becomes a problem. According to Henry’s Law, the O2 dissolved in blood at the alveolar-capillary membrane is proportional to the partial pressure of oxygen. (PO2)

  • When the difference is moderate, the human body can adapt.
  • However, many people will have problems adapting to low partial pressures of oxygen (PO2), especially if there is an underlying illness or the transition is rapid”
  • Acute mountain sickness
  • High-altitude pulmonary edema
  • High-altitude cerebral edema
54
Q

Scuba Diving Physiology

A

The opposite problem with Henry’s Law occurs when humans experience higher than normal pressures (e.g. scuba diving)

  • Partial pressures of nitrogen (Pn2) becomes huge!
  • This forces nitrogen into solution in the blood
  • Bigger problem: when diver ascends, N2 is released from solution and causes damage to alveolar-capillary membrane and joints and lung damage (“the bends”).
55
Q

External Respiration

A

Occurs at the alveolar-capillary membrane. External Respiration is the diffusion of atmospheric oxygen from the alveoli of the lungs to blood in the pulmonary capillaries. In exchange, CO2 in the blood coming from the tissues diffuses into alveolar capillaries and is exhaled.

56
Q

What are the 4 steps of External Respiration?

A

In order for a molecule of a gas to pass from the alveolar space into the blood, it must cross these layers:

  1. across the membrane and cytoplasm of the very thin type 1 alveolar cell;
  2. through the basement membrane of the type 1 alveolar cell
  3. through the basement membrane of the endothelial cell;
  4. across the membrane and cytoplasm of the very thin endothelial cell lining the capillary
    - the 2 basement membranes (2&3) are fused
    - the entire distance to be traveled is about 0.5 um
57
Q

Pulmonary Ventilation

A

Pulmonary ventilation (V): is the amount of air entering the lungs each minute. ( the V is for ventilation, the dot indicates per minute)

58
Q

Alveolar Ventilation

A

Alveolar ventilation (VA): is the amount of air entering the alveoli each minute. If air enters your lungs, but does not enter the alveoli, then its gases cannot be absorbed into the blood.

59
Q

Perfusion

A

Perfusion (Q): is the amount of blood that flows through the lung capillaries each minute.

60
Q

Ventilation-Perfusion Coupling

A

The matching of pulmonary blood flow to oxygen

  • under hypoxic conditions, pulmonary blood vessels constrict
  • forces or shunts blood to areas of higher oxygen

In healthy individuals:
- VA = 4.5 L/min
- Q = 5.0 L/min
Ideally, the ventilation/perfusion ratio (VA/Q) is about 1
If no air enters lungs, VA/Q=0
- blood flows but no gas exchange takes place
If air enters lungs but blood does not flow, VA/Q=
-for example, if blood clot lodges in lung (pulmonary embolism)
- blood is not oxygenated and cannot release waste CO2

61
Q

Internal Respiration

A

Internal respiration is a respiratory process that occurs in capillaries in which:

  • O2 is delivered to the body’s tissues
  • CO2 is picked up and carried back to the lungs for excretion.
62
Q

Internal Respiration: Oxygen

A

Almost all the oxygen is carried by hemoglobin (98.5%)

  • hemoglobin picks up O2 where the concentration (partial pressure) is highest and releases O2 where its partial pressure is lowest
  • alveolar air has the highest Po2 (105 mmHg)
  • tissue has the lowest Po2 (40 mmHg)
63
Q

Internal Respiration: Carbon Dioxide

A

Most of the carbon dioxide is carried by bicarbonate ion (HCO3-).

  • high partial pressure of CO2 drives the formation of HCO3-
  • tissue has the highest PCO2 (45mmHg)
  • alveolar air has the lowest PCO2 (40mmHg)
64
Q

External vs. Internal Respiration

A

In summary, external respiration is the exchange of gases between the pulmonary capillaries and the alveoli which contain atmospheric air. CO2 diffuses from the capillaries into the alveoli; O2 diffuses from the alveoli to the pulmonary capillaries.

Internal Respiration is the exchange of gases between the tissues and the systemic capillaries. Oxygen diffuses into the tissues, carbon dioxide diffuses from the tissues into the bloodstream.

65
Q

O2-Hemoglobin Saturation Curve

A

In alveolar air and arterial blood, PO2 is highest (about 100 mm Hg)

  • this corresponds to a hemoglobin saturation of about 97%
  • clinically, this is the “O2 sat”

At tissues, PO2 is lowest (about 40 mm Hg or less)

  • read up from the X axis and then across: only~75% of the hemoglobin molecules are carrying O2 under these conditions
  • remaining ~25% of O2 has been delivered to the tissues
66
Q

O2-Hemoglobin Saturation Curve: Effect of pH

A

Normal body pH is 7.40

If pH is lower, hemoglobin affinity curve shifts to right

  • less O2 bound at lung
  • more O2 delivered at tissues

If pH is higher, hemoglobin affinity curve shifts to left

  • opposite effect: more O2 bound at lung
  • less O2 delivered to tissues
67
Q

O2-Hemoglobin Saturation Curve: Effect of PCO2

A

Normal PCO2 (black curve)

If PCO2 is higher, hemoglobin affinity curve shifts to right

  • less O2 bound at lung
  • mores O2 delivered at tissues

If PCO2 is lower, hemoblobin affinity curve shifts to left.

  • opposite effect: more O2 bound at lung
  • less O2 delivered at tissues
68
Q

O2-Hemoglobin Saturation Curve: Effect of Temperature

A

Normal Temperature (black curve)

If temperature is higher, hemoglobin affinity curve shifts to right

  • less O2 bound at lung
  • mores O2 delivered at tissues

If temperature is lower, hemoglobin affinity curve shifts to left

  • opposite effect: more O2 bound at lung
  • less O2 delivered at tissues
69
Q

O2-Hemoglobin Saturation Curve: Effect of Pregnancy

A

Problem: if mother’s tissue and fetal tissues have the same O2 affinity, then how can baby’s tissues get oxygenated?

Solution: fetal hemoglobin (dashed line) has a higher affinity for O2 than maternity hemoglobin (solid line)

70
Q

How CO2 is Carried

A

About 70% of CO2 is carried as bicarbonate ion

About 23% is carried in hemoglobin
- remember, ~25% of O2 binding sites are now empty, so these sites (heme groups) can be used to carry CO2 now.

About 7% is dissolved as a gas in plasma
- like carbonation in soda

71
Q

Conversion of CO2 to Bicarbonate

A

The conversion of CO2 to bicarbonate to be carried in the plasma is a somewhat complicated process.

  • First, CO2 combines with H2O in the red blood cell to form carbonic acid (H2CO3)
  • Carbonic acid dissociates to HCO3- and H+. The bicarbonate ions leave the RBC, exchanging for Cl- ions. At the alveoli the reaction reverses and CO2 is exhaled.
72
Q

Buffers in the Human Body. Please refer to Objective 18 for Further Understanding.

A

A buffer acts as a H+ and/or OH- “sponge” so that pH is kept relatively constant.

The most important buffer system in human biology is the carbonic acid - bicarbonate buffer system.

When pH is low (7.40), [H+] is decreased. This pushes the reaction to the right and more bicarbonate ion is made.

73
Q

Hyperventilation

A

Excessive ventilation (V) leading to low blood (CO2) and high blood pH (alkalosis).

74
Q

Hypoventilation

A

Decreased ventilation (V) leading to high blood (CO2) and low blood pH (acidosis).

75
Q

Panting

A

Quick, shallow breaths. (i.e. respiratory rate may increase but might not increase V (per minute)

76
Q

Eupnea

A

Normal Respiration

77
Q

Hyperpnea

A

Increased respiratory rate

78
Q

Apnea

A

Temporary halt in respiration

79
Q

Control of Respiration - Neural Regulation: Medulla

A

The medulla rhythmicity area controls basic rhythm of respiration.

Inspiratory Center:

  • Stimulates diaphragm by the phrenic nerve
  • Stimulates external intercostals by intercostal nerves

Expiratory Center:

  • Inactive during quiet breathing
  • Stimulates internal intercostals and abdominal muscles to contract during forced exhalation
80
Q

Control of Respiration - Neural Regulation: Pons

A

Pneumotaxic Center
- limits the duration of inspiration to prevent lungs from getting too full.

Apneustic Center
- coordinates transition between inhalation and exhalation

81
Q

Other Source of Regulation

A

The medulla and pons control the basic rhythm of respiration, but inputs from other areas also have a role:

  • Our cerebral cortex has voluntary control when we want it
  • Emotions (limbic system) affect breathing
  • Hypercapnia (hypocarbia) (elevated PCO2), low O2, or acidosis (low pH) stimulate more rapid breathing
  • Bronchial stretch receptors, sensing overinflation, arrest breathing temporarily (Hering-Breuer reflex)
  • The hypothalamus, sensing a fever, increases breathing
  • Moderate pain increases breathing. Severe pain causes apnea - a temporary cessation of breathing.
82
Q

Chemoreceptors

A

Chemoreceptors send input to the inspiratory center to increase respirations if CO2 and/or H+ are high or PO2 is low.

Increased CO2, Increased H+, and Decreased O2 = Increase in rate and depth of breathing.

83
Q

Can you die holding your breath?

A

If the PO2 drops below from a normal level of 100 mm Hg to above 55 mm Hg, chemoreceptors are stimulated. You are consciously holding your breath through the influence of the motor cortex. If your PO2 drops below a certain level, fainting follows, and the brainstem will take over the work of breathing while you are unconscious.

84
Q

Embryology of the Respiratory System

A

Lungs begin to develop as buds on the pharynx at fourth week (after day 21)

  • Primary and secondary bronchi visible at fifth week (days 29-35)
  • Tertiary bronchi at sixth week (days 36-42)
  • Lobes of lung at evident at end of eighth week (day 56)
  • Normal pregnancy is 40 weeks; earliest viable premature babies are about 23 weeks gestation.
85
Q

Surfactants Reduce Surface Tension

A

Detergents (soaps) are surfactants. These are named because they reduce surface tension in water.
- One end of a surfactant molecule likes grease, the other end likes water.

86
Q

Surfactants in the Lung

A

Surfactant secreted by cells in the lung reduce surface tension. This keeps the delicate structure of the lung from collapsing. Without surfactant (e.g. premature babies), lungs cannot inflate.

87
Q

Embryology of the Respiratory System

A

Surfactant production appears in type II alveolar cells of developing lung at about 20 weeks.

Failure to make sufficient surfactant at birth leads to infant respiratory distress syndrome (IRDS).

  • incidence is about 2/3 of infants, less than 28 weeks
  • not usually seen after 38 weeks

Also, younger viable infants (23-28 weeks) have anatomically immature lungs.
- surfactant replacement may not be enough to save this infants life

88
Q

What are 5 Type of Surfactants used for Neonates?

A
  • Exosurf (synthetic)
  • Survanta (minced cow lung)
  • Infasurf (calf lung)
  • Curosurf (pig lung)
  • Surfaxin (synthetic)

Anatomy and Physiology 1111 (7 decks)

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