Anatomi dan Fisiologi Anatomi dan Fisiologi Jalan Nafas Jalan Nafas

The Body’s Need for The Body’s Need for OxygenOxygen

Living tissue must have oxygen to survive. Living tissue must have oxygen to survive. Brain death in humans occurs within 6 to 10 Brain death in humans occurs within 6 to 10

minutes of tissue anoxia. minutes of tissue anoxia. Rapid and safe airway control is paramount to the Rapid and safe airway control is paramount to the

successful management of critically ill and injured successful management of critically ill and injured patients. patients.

Airway AnatomyAirway Anatomy

Upper airway structures include the:Upper airway structures include the:Mouth Mouth NoseNosePharynxPharynx Oropharynx Oropharynx

The lower airway structures include the:The lower airway structures include the:LarynxLarynxTracheaTrachea BronchiBronchiBronchiolesBronchioles AlveoliAlveoliLungsLungs

..

NoseNose Nasal cavityNasal cavity PharynxPharynx LarynxLarynx TracheaTrachea BronchiBronchi BronchiolesBronchioles Respiratory bronchiolesRespiratory bronchioles Alveolar ductsAlveolar ducts AlveoliAlveoli

Conducting zone• Transport, cleanse, warm and Transport, cleanse, warm and humidify incoming air humidify incoming air • Not involved in gas exchange Not involved in gas exchange • “ “Anatomical Dead Space”Anatomical Dead Space”

Respiratory zoneFunction in gas Function in gas exchangeexchange

tongueteeth

mandible

lips

oropharyng

hard palate

soft palate

MOUTH

NOSEConcha superior

Concha medius

Concha inferior

sphenoid sinus

frontal sinus

PHARYNG:

- Nasopharyng

- Oropharyng (throat)

- Laryngopharyng

hard palate

tongue

soft palate

tonsilla palatina

epiglottis

vocal cordtrachea

concha

nasopharyng

uvula

oropharyng

laryngopharyng

UPPERLOWER

eustachian opening

frontal sinus

sphenoid sinus

LARYNG (VOICE BOX)

- separates pharyng and trachea- cartilages, membrane, ligaments- ♂ 45 mm long, Ø 35 mm- ♀ 35 mm long, Ø 25 mm

FUNCTION- Patent airway

- To act as a switching mechanism to route air and food into the proper channels- Voice production

Framework of the Larynx

thyrohyoid ligament

CRICOTHYROTOMY

- acute, life threatening upper airway obstruction- intubation not possible- conventional airway management not possible

SELLICK’S MANEUVRESELLICK’S MANEUVREUsed to prevent gastric distention Used to prevent gastric distention

TechniqueTechniqueApply slight pressure Apply slight pressure anteriorly over anteriorly over cricoid cartilagecricoid cartilageCloses off esophagusCloses off esophagus

Sellick’s Sellick’s ManueverManuever

The intrinsic muscles of the larynx attach to the Arytenoid cartilage, and allow for movement of the vocal cords.

Movements of Movements of Vocal CordsVocal Cords

Glottis & Epiglottis

glottis

epiglottis

TRACHEA

TRACHEA VIEWED FROM ABOVE

primary bronchus

secondary bronchus

tertiary bronchusbronchiole

terminalbronchiole

BRONCHIAL TREE

respiratory zone

…hair like projection called cilia line the primary bronchus to remove microbes and debris from the interior of the lungs…

Notice that the right is more vertical and fatter than the left which turns at a bit of an angle.

Respiratory bronchioles,Respiratory bronchioles,alveolar ducts, alveolar alveolar ducts, alveolar

sacssacs

Alveolar sacs Alveolar sacs look like look like clusters of clusters of grapesgrapes

The “individual The “individual grapes” are grapes” are alveolialveoli

Alveolar sacsAlveolar sacs AlveoliAlveoli

air-blood barrier

Respiratory PhysiologyRespiratory PhysiologyBreathingBreathing

Pulmonary Ventilation Pulmonary Ventilation the movement of air into and out of the movement of air into and out of the lungsthe lungs

Gas exchange occurs due to a pressure gradient (partial Gas exchange occurs due to a pressure gradient (partial pressures of gas)pressures of gas)

Two phasesTwo phases Inspiration: Breathing inInspiration: Breathing in

Active processActive process Expiration: Breathing outExpiration: Breathing out

Passive processPassive process

Inspiration isInspiration is initiated by a stimulus in the initiated by a stimulus in the respiratory center of the brain. respiratory center of the brain. The signal is transmitted to the diaphragm via the The signal is transmitted to the diaphragm via the

phrenic nerve. phrenic nerve. The impulse causes the diaphragm to contract or The impulse causes the diaphragm to contract or

flatten. flatten. This causes intrapulmonic pressure to fall below This causes intrapulmonic pressure to fall below

atmospheric pressure and air is drawn into the atmospheric pressure and air is drawn into the lungs like a vacuum. lungs like a vacuum.

The ribs elevate and expand, the alveoli inflate, The ribs elevate and expand, the alveoli inflate, and oxygen and carbon dioxide diffuse across the and oxygen and carbon dioxide diffuse across the membrane.membrane.

Respiratory pressures are always described relative Respiratory pressures are always described relative to atmospheric pressureto atmospheric pressure

Boyle’s Law:Boyle’s Law: Volume of gas is inversely proportional to Volume of gas is inversely proportional to

pressure (if temperature constant)pressure (if temperature constant)

Volume= Volume= Constant Constant PressurePressure So, when the volume of the container increases So, when the volume of the container increases

(expansion of the lungs), the pressure decreases(expansion of the lungs), the pressure decreases

Pressure in Thoracic Pressure in Thoracic CavityCavity

As the size of As the size of closed container closed container decreases, decreases, pressure inside pressure inside is increaseis increase

Same number Same number of molecules of molecules striking a striking a smaller smaller surface areasurface area

Boyle’s Law

Atmospheric Pressure (PAtmospheric Pressure (Patmatm)) - pressure exerted by - pressure exerted by the air surrounding the body. At sea level its the air surrounding the body. At sea level its equal to 760mmHg. equal to 760mmHg.

Intrapulmonary Pressure (PIntrapulmonary Pressure (Palvalv)) - pressure exerted by - pressure exerted by the air within the alveoli. It rises and falls during the air within the alveoli. It rises and falls during inspiration and expiration, but it always inspiration and expiration, but it always equalizes with atmospheric pressure. equalizes with atmospheric pressure.

Intrapleural Pressure (PIntrapleural Pressure (Pipip)) - pressure within the - pressure within the pleural cavity. It is always lower than both pleural cavity. It is always lower than both atmospheric pressure and intrapulmonary atmospheric pressure and intrapulmonary pressure.pressure.

Pressure in Thoracic Pressure in Thoracic CavityCavity

pleura parietalis

pleura visceralis (attach to the lung)

pleural cavity

alveoli

PPatm

PPalvalv

Pip

• PPatm 760 mmHg• PPalv alv rises and falls during inspiration and expiration, but it always equalizes with atmospheric pressure• Pip < Patm or Palv

It is elastic and has a It is elastic and has a tendency to recoil tendency to recoil

Ribs want to expandRibs want to expand outward outward

Lungs want to collapseLungs want to collapse

Since the pressure in the plural space is lower Since the pressure in the plural space is lower than in the alveoli, the alveoli do not collapse.than in the alveoli, the alveoli do not collapse.

Lung Tissue

Alveolar pressure falls below atmospheric Alveolar pressure falls below atmospheric pressure.pressure.

Contraction of the diaphragm and external Contraction of the diaphragm and external intercostal muscles increases the size of the intercostal muscles increases the size of the thorax (thereby decreasing the intra-pleural thorax (thereby decreasing the intra-pleural pressure) and the lungs expand.pressure) and the lungs expand.

Intra-pleural (thoracic) pressure is always 4 Intra-pleural (thoracic) pressure is always 4 mmHg less than the atmospheric pressure just mmHg less than the atmospheric pressure just before inhalation (756 mm Hg)before inhalation (756 mm Hg)

Inspiration

Expansion of the lungs decreased alveolar Expansion of the lungs decreased alveolar pressure to 758 mm Hgpressure to 758 mm Hg

Atmospheric pressure is 760 mm HgAtmospheric pressure is 760 mm Hg Air flows into the lungs because of this Air flows into the lungs because of this

pressure gradientpressure gradient Inspiration causes intra-pleural pressure to Inspiration causes intra-pleural pressure to

decrease to 754 mm Hgdecrease to 754 mm Hg

Inspiration

Air is forced out Air is forced out of the lungs as of the lungs as the muscles the muscles relax reducing relax reducing the volume of the volume of the chest cavity the chest cavity and increasing and increasing the pressurethe pressure

EXPIRATION

Occurs when alveolar pressure is higher than Occurs when alveolar pressure is higher than atmospheric pressureatmospheric pressure

762 mm Hg762 mm Hg Elastic recoil of the chest wall and lungs (main Elastic recoil of the chest wall and lungs (main

force) force) and the relaxation of the diaphragm and the relaxation of the diaphragm increases intra-pleural and alveolar pressure and increases intra-pleural and alveolar pressure and decreases lung volumedecreases lung volume

Air moves outAir moves out Quiet breathing does not take any effort (no Quiet breathing does not take any effort (no

muscles are being contracted)muscles are being contracted)

EXPIRATION

3 Major Factors3 Major Factors Alveolar surface tensionAlveolar surface tension ComplianceCompliance Airway resistanceAirway resistance

Pulmonary VentilationPulmonary Ventilation

Surface tension causes the alveoli to Surface tension causes the alveoli to assume the smallest diameterassume the smallest diameter Major component of lung elastic recoilMajor component of lung elastic recoil

Surfactant is a phospholipid produced by Surfactant is a phospholipid produced by Type II cells in alveolar wallsType II cells in alveolar walls Alters surface tension below the surface Alters surface tension below the surface

tension of pure watertension of pure water Prevents alveolar collapse following expirationPrevents alveolar collapse following expiration If surface tension is too high, alveoli collapse If surface tension is too high, alveoli collapse

and great effort is needed to reopen themand great effort is needed to reopen them

Alveolar surface tensionAlveolar surface tension

ComplianceComplianceRatio of volume changes caused by pressure changes Ratio of volume changes caused by pressure changes V/V/PP

• Lung ComplianceLung Compliance• Thoracic wall ComplianceThoracic wall Compliance

Low compliance To get desired volume there must be higher pressureTo get desired volume there must be higher pressure

High compliance Low pressure will give high tidal volume Low pressure will give high tidal volume

stiff Elastis

LOW COMPLIANCE

HIGH COMPLIANCE

BALLOON

COMPLIANCE COMPLIANCE (COMPL)(COMPL)

P-V P-V LOOPLOOP

15

30

250

500

0

P

Vol

500

500

250

250

15

30

15

30

LOW COMPLIANCE

HIGH COMPLIANC

ENORMAL

PEEP 5INSPIRATION

EKSPIRATION

Spontaneus breathing

The walls of the respiratory passageways have The walls of the respiratory passageways have resistance to the normal flow of air into the resistance to the normal flow of air into the lungslungs

The smaller the diameter, the greater the The smaller the diameter, the greater the resistanceresistance

Any condition that obstructs the air passageway Any condition that obstructs the air passageway increases resistance, and more pressure is need increases resistance, and more pressure is need to force air throughto force air through AsthmaAsthma Inflammation due to infectionInflammation due to infection EmphysemaEmphysema

ResistanceResistance

FLOW = PRESSURE

RESISTANCE

BRONCHOCONSTRICTION: HISTAMIN

OBSTRUCTION: MUCUS / SECRET

AIRWAY RESISTANCE (RAW)

FLOW = PRESSURE

RESISTANCE

BRONCHOSPASM TUMOUR / SECRET

TOO SMALL ETT

COLLAPSE/ATELECTASIS

AIRWAY RESISTANCE (RAW)

Partial PressurePartial Pressure Dalton’s LawDalton’s Law: each gas in a mixture of : each gas in a mixture of

gases exerts its own pressure as if all gases exerts its own pressure as if all other gases were not presentother gases were not present Air 78% nitrogen, 21% oxygen, 1% other Air 78% nitrogen, 21% oxygen, 1% other

(CO(CO22)) Partial pressure of a gas is the pressure Partial pressure of a gas is the pressure

of an individual gas in a mixture.of an individual gas in a mixture. PO2 21% X 760 = 159.6 mm HgPO2 21% X 760 = 159.6 mm Hg Total pressure is adding all the partial Total pressure is adding all the partial

pressurespressures

Exchange of OExchange of O22 and CO and CO22

OO22 and CO and CO22 Diffuse from areas of higher Diffuse from areas of higher partial pressures to areas of lower partial partial pressures to areas of lower partial pressurepressure

Results in exchange of OResults in exchange of O22 and CO and CO2 2 in the in the alveolialveoli Alveoli: PAlveoli: PAAOO22=105 =105 mm Hg, mm Hg, PCO2=40PCO2=40 mm Hgmm Hg Capillaries: PCapillaries: PvvOO22=40 =40 mm Hg, mm Hg, PPVVCOCO2 2 =45 =45 mm Hgmm Hg Pulmonary veinPulmonary vein::PPAAOO22=100 PCO2=40=100 PCO2=40 mm Hgmm Hg

O2 and CO2 Diffuse from areas of higher partial pressures to areas of lower partial pressure

Exchange of O2 and Exchange of O2 and CO2CO2

RELATIONSHIP BETWEEN VENTILATION (V) AND PERFUSION (Q)

Normal V/Q = 1

V/Q > 1

alveolar dead spaceV/Q < 1

shunt

TERIMA KASIH