Thoracic SurgeryThoracic SurgeryEmbryology,Surgical Embryology,Surgical

Anatomy,Pulmonary physiologyAnatomy,Pulmonary physiology

Dr.Ahmed Al-AzzawiDr.Ahmed Al-Azzawi

M.B.Ch.B,F.I.C.M.SM.B.Ch.B,F.I.C.M.S

Cardiothoracic&Vascular SurgeonCardiothoracic&Vascular Surgeon

University of SulaimaniUniversity of Sulaimani

College of MedicineCollege of Medicine

INTRODUCTIONINTRODUCTION

Thoracic surgery focuses primarily on Thoracic surgery focuses primarily on the organs that support the delicate the organs that support the delicate sequence of events that move air to sequence of events that move air to blood and blood to tissues.blood and blood to tissues.

Air with adequate oxygen content must Air with adequate oxygen content must pass the upper airway, the trachea and pass the upper airway, the trachea and the bronchi to reach the alveoli, the bronchi to reach the alveoli, properly warmed and humidified , for properly warmed and humidified , for movement across alveolar membrane.movement across alveolar membrane.

Respiratory Respiratory systemsystem

EMBRYOLOGYEMBRYOLOGYThe respiratory system is an outgrowth of the The respiratory system is an outgrowth of the ventral wall of the foregut ,and the epithelium of ventral wall of the foregut ,and the epithelium of the larynx,trachea,bronchi,and alveoli originates in the larynx,trachea,bronchi,and alveoli originates in the endoderm.the endoderm.The cartilaginous,muscular,and connective tissue The cartilaginous,muscular,and connective tissue components arise in the mesoderm .components arise in the mesoderm .In the 4In the 4thth week of development ,the week of development ,the tracheoesophageal septum seperates the trachea tracheoesophageal septum seperates the trachea from the foregut ,dividing the foregut into the lung from the foregut ,dividing the foregut into the lung bud anteriorly and the esophagus posteriorly .bud anteriorly and the esophagus posteriorly .The lung bud developes into two main The lung bud developes into two main bronchi ,the right forms three secondary bronchi bronchi ,the right forms three secondary bronchi and three lobes ;the left forms two secondary and three lobes ;the left forms two secondary bronchi and lobes . bronchi and lobes .

After apseudoglandular (5_16 weeks) and After apseudoglandular (5_16 weeks) and canalicular (16_26weeks)phase ,cells of the cuboidal canalicular (16_26weeks)phase ,cells of the cuboidal lined bronchioles change into thin ,flat cells lined bronchioles change into thin ,flat cells type I type I aleveolar epithelial cells,aleveolar epithelial cells,in the seventh month,gas in the seventh month,gas exchange between the blood and air in the exchange between the blood and air in the primitive primitive aleveolialeveoli is possible . is possible .

Before birth the lungs are filled with fluid with little Before birth the lungs are filled with fluid with little protein,some mucous,and protein,some mucous,and surfactant ,surfactant ,which which producedproduced by by type II aleveolar epithelial cellstype II aleveolar epithelial cells and and which forms aphospholipid coat on the aleveolar which forms aphospholipid coat on the aleveolar memberanes .memberanes .

At the beginning of the respiration the lung fluid is At the beginning of the respiration the lung fluid is resorbed except for the surfactant coat,which resorbed except for the surfactant coat,which prevent the collapse of the aleveoli during expiration prevent the collapse of the aleveoli during expiration by reducing the surface tension at the air _blood by reducing the surface tension at the air _blood capillary interface .capillary interface .

. .

Absent or insufficient surfactant in the Absent or insufficient surfactant in the premature baby causes RDS because premature baby causes RDS because of the collapse of the primitive aleveoli of the collapse of the primitive aleveoli (hyaline memberane disease ).(hyaline memberane disease ).

Growth of the lungs after birth is due Growth of the lungs after birth is due to an increase in the number of to an increase in the number of respiratory bronchioles and aleveoli respiratory bronchioles and aleveoli and not to an increase in the size of and not to an increase in the size of the aleveoli ,new aleveoli are formed the aleveoli ,new aleveoli are formed during the first 10 years of postnatal during the first 10 years of postnatal lifelife

With growth the lung buds expand into the body With growth the lung buds expand into the body cavity ,the spaces for the lungs are gradualy cavity ,the spaces for the lungs are gradualy filled by the expanding lung buds .filled by the expanding lung buds .

The mesoderm which covers the outside of the The mesoderm which covers the outside of the lung ,developes into the visceral pleura .lung ,developes into the visceral pleura .

The somatic mesoderm layers becomes the The somatic mesoderm layers becomes the parietal pleura.parietal pleura.

The space between the parietal and visceral The space between the parietal and visceral pleura is the pleural cavity.pleura is the pleural cavity.

During further growth secondary bronchi divide During further growth secondary bronchi divide repeatedly forming10 tertiary(segmental)bronchi repeatedly forming10 tertiary(segmental)bronchi in the right lung and 8 in the left creating the in the right lung and 8 in the left creating the bronchopulmonary segments of the adults lung . bronchopulmonary segments of the adults lung .

Maturation of the lungsMaturation of the lungs

Up to the seventh month ,the bronchioles divide Up to the seventh month ,the bronchioles divide continously into more and smaller canals,and the continously into more and smaller canals,and the vascular supply increased steadly .vascular supply increased steadly .

During the seventh month ,sufficient numbers of During the seventh month ,sufficient numbers of capillaries are present to guarantee adequate gas capillaries are present to guarantee adequate gas exchange and the premature infant is able to exchange and the premature infant is able to survive.survive.

Fetal breathing movements begin before birth and Fetal breathing movements begin before birth and cause aspiration of amniotic fluid .These cause aspiration of amniotic fluid .These movements are important for stimulating lung movements are important for stimulating lung development and conditioning respiratory muscles.development and conditioning respiratory muscles.

Respiratory movements after birth bring air into Respiratory movements after birth bring air into the lungs,which expand and fill the pleural cavity the lungs,which expand and fill the pleural cavity

Growth of the lungs after birth is due Growth of the lungs after birth is due primarly to an increase in the number primarly to an increase in the number of respiratory bronchioles and of respiratory bronchioles and aleveoli.aleveoli.

It is estimated that only one –sixth of It is estimated that only one –sixth of the adult number of aleveoli are the adult number of aleveoli are present at birth.present at birth.

RespirationRespiration

Respiration includes the movement Respiration includes the movement of air into and out of the lungs .of air into and out of the lungs .

The exchange of gases between the The exchange of gases between the air and the blood.air and the blood.

The transport of gases in the blood.The transport of gases in the blood. The exchange of gases between the The exchange of gases between the

blood and tissue.blood and tissue.

Anatomy of the respiratory Anatomy of the respiratory systemsystem

The respiratory system consists of The respiratory system consists of the nose,the nasal cavity,the the nose,the nasal cavity,the pharynx,the larynx,the trachea,the pharynx,the larynx,the trachea,the bronchi,and the lungs.bronchi,and the lungs.

The upper respiratory tract refers to The upper respiratory tract refers to the nose,nasal cavity,pharynx,and the nose,nasal cavity,pharynx,and associated structures.associated structures.

The lower respiratory tract includes The lower respiratory tract includes the larynx,trachea,bronchi,and the larynx,trachea,bronchi,and lungs.lungs.

The lung apices rise well above the level of The lung apices rise well above the level of the clavicles anteriorly and the scapula the clavicles anteriorly and the scapula posteriorly.posteriorly.

The diaphragm rises as high as the level of The diaphragm rises as high as the level of the nipple.the nipple.

The framework of the thoracic cage consists The framework of the thoracic cage consists of the sternum, 12 thoracic vertebrae,10 of the sternum, 12 thoracic vertebrae,10 pairs of the ribs that end anteriorly in pairs of the ribs that end anteriorly in segments of cartilage,and two pairs of segments of cartilage,and two pairs of floating ribs .floating ribs .

The thoracic inlet has arigid structural ring The thoracic inlet has arigid structural ring formed by the sternal manubrium,the formed by the sternal manubrium,the short,semicircular first ribs,and the short,semicircular first ribs,and the vertebral column. vertebral column.

TRACHEATRACHEA The trachea is amemberanous tube that The trachea is amemberanous tube that

consists of connective tissue and smooth consists of connective tissue and smooth muscle,reinforced with 16 to 20 C-shaped muscle,reinforced with 16 to 20 C-shaped pieces of cartillage.pieces of cartillage.

The adult trachea is about 1.4 to 1.6cm in The adult trachea is about 1.4 to 1.6cm in diameter and has an average length of 11 diameter and has an average length of 11 cm (range 10-13 cm).cm (range 10-13 cm).

It begins immediately inferior to cricoid It begins immediately inferior to cricoid cartillage.cartillage.

It divides into the right and left primary It divides into the right and left primary bronchi at the level of T5.bronchi at the level of T5.

The esophagus lies immediately posterior to The esophagus lies immediately posterior to the trachea.the trachea.

BRONCHIBRONCHI

The bronchi may be classified as The bronchi may be classified as primary ,secondary(lobar),and primary ,secondary(lobar),and tertiary(segmental).tertiary(segmental).

The right and left 1ry bronchus arise The right and left 1ry bronchus arise from the bifurcation of the trachea from the bifurcation of the trachea at T4/T5 intervertebral disc.at T4/T5 intervertebral disc.

The right primary bronchus is The right primary bronchus is shorter larger in diameter,and more shorter larger in diameter,and more vertically oriented than the left.vertically oriented than the left.

Secondary bronchus Secondary bronchus (lobar)(lobar)

There are three 2dry bronchi in the There are three 2dry bronchi in the right lung upper,middle and lower.right lung upper,middle and lower.

There are two secondary bronchi in There are two secondary bronchi in the left uppetr,and lower.the left uppetr,and lower.

Tertiary bronchusTertiary bronchus

There are 10 tertiary bronchi in the There are 10 tertiary bronchi in the right lung :right lung :

1.1. The right superior lobar bronchus The right superior lobar bronchus branches ;apical,posterior,and branches ;apical,posterior,and anterior.anterior.

2.2. Right middle;medial,lateral.Right middle;medial,lateral.

3.3. Right inferior:superior,anterior Right inferior:superior,anterior basal,posterior basal,medial basal,posterior basal,medial basal,lateral basal.basal,lateral basal.

In the left lung there are 8 tertiary In the left lung there are 8 tertiary bronchi:bronchi:

1.1. Left superior lobar Left superior lobar bronchus ;apicoposteror,anterior.bronchus ;apicoposteror,anterior.

2.2. Lingular bronchus;superior Lingular bronchus;superior lingular,inferior lingular.lingular,inferior lingular.

3.3. Inferior lobar Inferior lobar bronchus;superior,anteromedial bronchus;superior,anteromedial basal,posterior basal,lateral basal.basal,posterior basal,lateral basal.

Carina:Carina: Keel-shaped cartillage lying within the Keel-shaped cartillage lying within the

tracheal bifurcation.tracheal bifurcation. Carina trachealis is an important Carina trachealis is an important

landmark during endoscopy of the landmark during endoscopy of the broncheal tree.broncheal tree.

LungsLungs

Oblique fissure: Oblique fissure: Deep groove in the surface of the lung that Deep groove in the surface of the lung that

separates the upper lobe from the lower lobe separates the upper lobe from the lower lobe (both lungs)and the middle lobe from the lower (both lungs)and the middle lobe from the lower lobe (right lung).lobe (right lung).

Oblique fissure extends from the level of T3 Oblique fissure extends from the level of T3 vertebrae posteriorly to the 6vertebrae posteriorly to the 6thth costochondral costochondral junction anteriorly.junction anteriorly.

Horizental fissure:Horizental fissure: Deep groove in the surface of the lung that Deep groove in the surface of the lung that

separates the middle lobe from the upper lobe separates the middle lobe from the upper lobe (right lung only).(right lung only).

It extends from the 5It extends from the 5thth rib at the mid-axillary line rib at the mid-axillary line along the 4along the 4thth rib to the sternum anteriorly. rib to the sternum anteriorly.

Pleural cavitiesPleural cavities

The lungs are contained within the The lungs are contained within the thoracic cavity.thoracic cavity.

Each lung is surrounded by Each lung is surrounded by aseparate pleural cavity.aseparate pleural cavity.

Each pleural cavity is lined with Each pleural cavity is lined with aserous memberane called the aserous memberane called the pleura.pleura.

PLEURAPLEURA

Serous membrane lining the pleural cavity.Serous membrane lining the pleural cavity. There are two types of pleura:visceral pleura There are two types of pleura:visceral pleura

covers the lungs ,parietal pleura lines the covers the lungs ,parietal pleura lines the inner surfaces of the walls of pleural inner surfaces of the walls of pleural cavity,parietal pleura is sensitive to pain but cavity,parietal pleura is sensitive to pain but visceral pleura is not sensitive to pain.visceral pleura is not sensitive to pain.

1.1. Cervical parietal pleura (sibson,s fascia or Cervical parietal pleura (sibson,s fascia or suprapleural membrane)also called cupula or suprapleural membrane)also called cupula or cervical dome of pleura it extends above the cervical dome of pleura it extends above the level of the 1level of the 1stst rib into the root of the neck. rib into the root of the neck.

2.Costal parietal pleura:on the inner 2.Costal parietal pleura:on the inner surfaces of the ribs,costal surfaces of the ribs,costal cartilages,and intercostal mm.cartilages,and intercostal mm.

3.Mediastinal parietal pleura:on the 3.Mediastinal parietal pleura:on the lateral surface of the mediastinum.lateral surface of the mediastinum.

4.Pulmonary ligament:fold of pleura 4.Pulmonary ligament:fold of pleura located below the root of the lung located below the root of the lung where the visceral and the where the visceral and the medistinal parietal pleura are medistinal parietal pleura are continuous with each other.continuous with each other.

Blood supplyBlood supply

Pulmonary trunk from the right Pulmonary trunk from the right ventricle gives right and left ventricle gives right and left pulmonary arteries which supply the pulmonary arteries which supply the lungs with deoxygenated blood .lungs with deoxygenated blood .

Pulmonary artery:Pulmonary artery:Right: gives superior lobar artery to the Right: gives superior lobar artery to the

superior lobe and inferior lobar a.to superior lobe and inferior lobar a.to the middle and inferior lobe,the middle and inferior lobe,

Left:sup.lobar a.to the sup. Lobe and Left:sup.lobar a.to the sup. Lobe and inferior lobar a. to inferior lobe. inferior lobar a. to inferior lobe.

Pulmonary vein drains into left Pulmonary vein drains into left atrium usualy two pulmonary atrium usualy two pulmonary veins :superior and inferior.veins :superior and inferior.

Bronchial arteries:Bronchial arteries:

1.1. Left bronchial artery arise from Left bronchial artery arise from descending thoracic aorta there are descending thoracic aorta there are usualy two left bronchial arteries.usualy two left bronchial arteries.

2.2. Right bronchial a.from the 3Right bronchial a.from the 3rdrd right right posterior intercostal or may arise posterior intercostal or may arise from the left bronchial artery.from the left bronchial artery.

Ventilation and lung Ventilation and lung volumesvolumes

Changing thoracic volumesChanging thoracic volumes Inspiration occurs when the diaphragm Inspiration occurs when the diaphragm

contracts and the external intercostal contracts and the external intercostal mm lift the rib cage,thus increasing the mm lift the rib cage,thus increasing the volume of the thoracic cavity .volume of the thoracic cavity .

Expiration can be passive or Expiration can be passive or active .Passive expiration during quiet active .Passive expiration during quiet breathing occures when the mm of breathing occures when the mm of inspiration relax inspiration relax

Pressure changes and Pressure changes and airflowairflow

Respiratory mm cause changes in Respiratory mm cause changes in thoracic volume,which cause changes thoracic volume,which cause changes in aleveolar volume and pressure.in aleveolar volume and pressure.

During inspiration ,air flows into the During inspiration ,air flows into the aleveoli bec.atmospheric presure is aleveoli bec.atmospheric presure is greater than aleveolar pressure.greater than aleveolar pressure.

During expiration,airflows out of the During expiration,airflows out of the aleveoli bec.aleveolar pressure is aleveoli bec.aleveolar pressure is greater than atmospheric pressure.greater than atmospheric pressure.

Lung RecoilLung Recoil

The lungs tend to collapse bec. Of The lungs tend to collapse bec. Of the elastic recoil of the connective the elastic recoil of the connective tissue and surface tension of the tissue and surface tension of the fluid lining the aleveoli.fluid lining the aleveoli.

The lungs normally do not collapse The lungs normally do not collapse bec. Surfactant reduces the surface bec. Surfactant reduces the surface tension of the fluid lining the aleveoli tension of the fluid lining the aleveoli and pleural pressure is less than and pleural pressure is less than aleveolar pressur.aleveolar pressur.

Changing Aleveolar Changing Aleveolar VolumeVolume

Increasing thoracic volume results in Increasing thoracic volume results in decreased pleural pressure,increased decreased pleural pressure,increased aleveolar volume,decreased aleveolar aleveolar volume,decreased aleveolar pressure,and air movement into the pressure,and air movement into the lungs.lungs.

Decreasing thoracic volume results in Decreasing thoracic volume results in increased pleural pressure,decreased increased pleural pressure,decreased aleveolar volume,increased aleveolar aleveolar volume,increased aleveolar pressure,and air movement out of the pressure,and air movement out of the lungs.lungs.

Pulmonary Volume and Pulmonary Volume and CapacitiesCapacities

There are four pulmonary volumes:tidal There are four pulmonary volumes:tidal v.,inspiratory reserve,expiratory v.,inspiratory reserve,expiratory reserve,and residual volume.reserve,and residual volume.

Pulmonary capacities are the sum of Pulmonary capacities are the sum of two or more pulmonary volumes and two or more pulmonary volumes and include vital capacity and total lung include vital capacity and total lung capacity.capacity.

The forced expiratory vital capacity The forced expiratory vital capacity measures the rate at which air can be measures the rate at which air can be expelled from the lungs. expelled from the lungs.

Pulmonary Pulmonary physiology physiology

. . Preoperative evaluation and perioperative care of a Preoperative evaluation and perioperative care of a

patient includespatient includes AA.. Tissue diagnosis of primary disease and decision if an Tissue diagnosis of primary disease and decision if an operative procedure is indicatedoperative procedure is indicated

BB.. Assessment of patient’s general conditionAssessment of patient’s general condition

CC.. Preoperative preparation and postoperative carePreoperative preparation and postoperative care

The Evaluation of pulmonary function includes assessment of The Evaluation of pulmonary function includes assessment of cardiac function, the oxygen carrying red cells, the lungs, cardiac function, the oxygen carrying red cells, the lungs,

chest wall and ventilatory muscular functionchest wall and ventilatory muscular function

The surgeon must make acareful The surgeon must make acareful assesment of the patient,s ability to assesment of the patient,s ability to withstand the contemplated procedure.withstand the contemplated procedure.

Major predictors of the postoperative Major predictors of the postoperative procedure include the extent of procedure include the extent of resection,pre-existing cardiopulmonary resection,pre-existing cardiopulmonary disease,age,and other co-morbid disease,age,and other co-morbid condition.condition.

Complete pulmonary function tests Complete pulmonary function tests including lung including lung volumes,spirometry,diffusion volumes,spirometry,diffusion capacity,and arterial blood gases. capacity,and arterial blood gases.

Pulmonary mechanicsPulmonary mechanics Vital capacity(VC),the amount of air that Vital capacity(VC),the amount of air that

can be forcefully expelled from can be forcefully expelled from amaximally inflated lung position.amaximally inflated lung position.

The forced expiratory volume in The forced expiratory volume in 1s(FEV1)is adynamic measurement of 1s(FEV1)is adynamic measurement of apatient ability to move volumes of air apatient ability to move volumes of air during units of time.during units of time.

The FEV1 usually is reported as The FEV1 usually is reported as apercentage of VC(FEV1/VC)as well as apercentage of VC(FEV1/VC)as well as actual volume,the FEV1 is reduced in actual volume,the FEV1 is reduced in obstructive airway disease.obstructive airway disease.

Blood-Gas DeterminationBlood-Gas Determination

Measurement of the arterial blood gases Measurement of the arterial blood gases and pH is routine in the preoperative and pH is routine in the preoperative evaluation.evaluation.

Ameasurement of arterial CO2 Ameasurement of arterial CO2 pressure(PaCO2)provides an immediate pressure(PaCO2)provides an immediate indication of the patient aleveolar indication of the patient aleveolar ventilation,any value >46 torr means that ventilation,any value >46 torr means that there is hypoventilation .there is hypoventilation .

PaO2 arterial O2 pressure is also PaO2 arterial O2 pressure is also important,normaly it greater than 85 torr.important,normaly it greater than 85 torr.

Lung physiologyLung physiology AA.. Well suited for efficient exchange of O2 andWell suited for efficient exchange of O2 and CO2CO2 with a large with a large

surface area and low perfusion pressure surface area and low perfusion pressure ((300 million alveoli)300 million alveoli)BB.. Gas exchange controlled by two pumpsGas exchange controlled by two pumps- - the right ventricle and the the right ventricle and the

chest cagechest cage--diaphragmdiaphragm CC.. Elastic recoil of lungs ejects gas and fibrous skeleton maintains Elastic recoil of lungs ejects gas and fibrous skeleton maintains

airway patencyairway patency DD.. Clinical evaluation of pulmonary functionClinical evaluation of pulmonary function 11history and physicalhistory and physical- - exercise toleranceexercise tolerance 2 2 CXR, ABGCXR, ABG 3 3 simple spirometrysimple spirometry 4 4 vital capacity vital capacity ((FVCFVC)- )- total exhaled volumetotal exhaled volume EE.. FEV1FEV1- - forced expiratory volume at one secondforced expiratory volume at one second- - indication of flowindication of flow1.1. FEV1FEV1 1000-2000 1000-2000 ml adequate for surgeryml adequate for surgery 2.FEV12.FEV1 800 800 ml or less preclude surgical resectionml or less preclude surgical resection DD.. Restrictive diseaseRestrictive disease- - vital capacity, inspiratory and expiratory vital capacity, inspiratory and expiratory

reserves are diminishedreserves are diminished- - can result from diseases of the lung, can result from diseases of the lung, pleura, chest cage and muscles pleura, chest cage and muscles --kyphoscoliosis, ARDS, pleural kyphoscoliosis, ARDS, pleural effusions or fibrosis Funcitonal residual volume is decreased effusions or fibrosis Funcitonal residual volume is decreased limited capacity to expand lungs but no difficulty emptying lungslimited capacity to expand lungs but no difficulty emptying lungs

EE.. Obstructive DiseaseObstructive Disease- - lung elastic recoil decreases, compromising lung elastic recoil decreases, compromising the forcethe force

of exhalation of exhalation - - most common form in clinical practice usually due to most common form in clinical practice usually due to smoking, damaged alveoli can lead to pulmonary HTN unsupported smoking, damaged alveoli can lead to pulmonary HTN unsupported airways leads to airway trapping and atelectasisairways leads to airway trapping and atelectasis

Ventilatory Pump and Work of BreathingVentilatory Pump and Work of BreathingAA.. Ventilatory pump consist of the thoracic cage and ventilatory Ventilatory pump consist of the thoracic cage and ventilatory

musclesmuscles BB.. The ventilatory pump is a suction pump which expands the The ventilatory pump is a suction pump which expands the

chest cage to pull air into the lungschest cage to pull air into the lungs CC.. Dyspnea signals that the work required of the ventilatory Dyspnea signals that the work required of the ventilatory

muscles has reachedmuscles has reached a level that exceeds the comfortable capacity of the patienta level that exceeds the comfortable capacity of the patient DD.. Thoracotomy creates a region of nonThoracotomy creates a region of non--contractile muscles which contractile muscles which

lowers tidallowers tidal volume and increases respiratory ratevolume and increases respiratory rate EE.. Several disease processes can cause ventilatory pump failureSeveral disease processes can cause ventilatory pump failure 1 1 central depressioncentral depression 2 2 muscle paralysismuscle paralysis 3 3 fatiguefatigue 4 4 mechanical defects in the thoracic cagemechanical defects in the thoracic cage--trauma, posttrauma, post--surgicalsurgical aa) )

failure of ventilatory pump leads to atelectasis and decreased failure of ventilatory pump leads to atelectasis and decreased lung compliancelung compliance

bb) ) functional residual volume decreases with loss of functional functional residual volume decreases with loss of functional alveolialveoli

cc) ) postpost--operative pain controloperative pain control- - epidural can help prevent splinting epidural can help prevent splinting and therefore atelectasisand therefore atelectasis

Work capacity of ventilatory muscles are Work capacity of ventilatory muscles are trainabletrainable- - sedentary patients will poor muscle sedentary patients will poor muscle function as compared to active patientsfunction as compared to active patients

AA..Fluid Exchange and Lung Water blood circulating Fluid Exchange and Lung Water blood circulating through normal lung capillaries at normal rates through normal lung capillaries at normal rates and pressure causes a net fluid movement from the and pressure causes a net fluid movement from the capillaries into the lung interstitiumcapillaries into the lung interstitium..The filtered The filtered fluid is picked up by the lymphatics and returned to fluid is picked up by the lymphatics and returned to the circulation Management of fluid therapy is the circulation Management of fluid therapy is critical in postcritical in post--operative pulmonary resection operative pulmonary resection patients since this fluid balance is disruptedpatients since this fluid balance is disrupted

1.1. increased filtration postincreased filtration post--operativelyoperatively 2.2. decreased capillary bed and lymphatic massdecreased capillary bed and lymphatic mass 3.3. increased cardiac outputincreased cardiac output 4.4. must carefully titrate fluid balance especially in must carefully titrate fluid balance especially in

pneumonectomy patientspneumonectomy patients

Ventilation Ventilation --Perfusion Perfusion Incoordination effective gas Incoordination effective gas transfer relies on the transfer relies on the coordination of ventilation and coordination of ventilation and perfusionperfusion

AA.. VentilationVentilation--perfusion mismatch occurs postperfusion mismatch occurs post--operativelyoperatively

BB.. VV//Q mismatch is the most common form of postQ mismatch is the most common form of post--operative hypoxemiaoperative hypoxemia

CC.. Usually secondary to the development of Usually secondary to the development of atelectasisatelectasis

Shunt FractionShunt Fraction

Determines the fraction of blood Determines the fraction of blood ejected by the left ventricle that ejected by the left ventricle that has no gas exchange in the lungshas no gas exchange in the lungs

1.1. Patients with a shunt fraction > Patients with a shunt fraction > 0.15 to 0.20 are vulnerable to a low 0.15 to 0.20 are vulnerable to a low CC ..OO. .

2.2. Tissue oxygen delivery fallsTissue oxygen delivery falls

3.3. Pulmonary artery catheter should Pulmonary artery catheter should be placed to optimize Cbe placed to optimize C..OO. .

One Lung AnesthesiaOne Lung Anesthesia

AA.. Procedure of choice for pulmonary Procedure of choice for pulmonary resectionresection

BB.. Videothoracoscopy has increased Videothoracoscopy has increased demanddemand

CC.. Unventilated lung is perfused and is Unventilated lung is perfused and is a source of an intrapulmonary shunt a source of an intrapulmonary shunt that can lead to hypoxemiathat can lead to hypoxemia

DD.. Usually ventilated on 100 Usually ventilated on 100 % % oxygenoxygen

Pneumonectomy lung reduction Pneumonectomy lung reduction surgerysurgery

AA.. Derived from the observation of Derived from the observation of chest wall adaptation in lung chest wall adaptation in lung transplant patientstransplant patients

BB.. Bilateral stapling of peripheral lung Bilateral stapling of peripheral lung tissue to diminish lung volumestissue to diminish lung volumes

CC.. Reinforced with bovine pericardial Reinforced with bovine pericardial strips to prevent leaksstrips to prevent leaks

DD.. Improvement in symptoms andImprovement in symptoms and FEV1FEV1

EE.. Improves diaphragmatic motionImproves diaphragmatic motion

Summary of Evaluation of Gas Exchange Summary of Evaluation of Gas Exchange FunctionFunction- - background facts for assessing background facts for assessing pulmonary function are as followspulmonary function are as follows::

AA.. There is a large reserve in normal individualsThere is a large reserve in normal individuals BB.. Condition of the ventilatory muscles depends on Condition of the ventilatory muscles depends on

the physical state of the patientthe physical state of the patient CC.. As lung volume falls, airways in dependent As lung volume falls, airways in dependent

areas of the lung closeareas of the lung close DD.. With aging and smoking, airways close at With aging and smoking, airways close at

higher lung volumeshigher lung volumes EE.. VV//Q mismatch occurs with airway closureQ mismatch occurs with airway closure FF.. VV//Q mismatch requires increased alveolar Q mismatch requires increased alveolar

ventilation to maintain the same amount of gas ventilation to maintain the same amount of gas exchangeexchange

GG.. Spirometry measures the volumes o flung and Spirometry measures the volumes o flung and the ability to move airthe ability to move air

HH.. PaCO2PaCO2 is an indicator of adequacy of ventilationis an indicator of adequacy of ventilation II .. PaO2PaO2 is an indicator of adequacy of oxygenationis an indicator of adequacy of oxygenation

THANKS FOR ALL