bpd

Bronchopulmonary DysplasiaBronchopulmonary Dysplasia

Dr Varsha Atul ShahDr Varsha Atul Shah

DefinitionDefinition

Initially described in Initially described in 1967 by Northway 1967 by Northway using clinical, using clinical, radiographic, and radiographic, and histologic lung histologic lung changes in the changes in the preterm infant who preterm infant who had been treated with had been treated with oxygen and ventilator oxygen and ventilator therapy. (Average age therapy. (Average age 34 wks, wt 2.2 kg.)34 wks, wt 2.2 kg.)

DefinitionDefinition

Definition initially required an oxygen Definition initially required an oxygen requirement at 28 days and an requirement at 28 days and an abnormal chest radiograph. abnormal chest radiograph. Currently, most authors define BPD Currently, most authors define BPD as an oxygen requirement at 36 wks as an oxygen requirement at 36 wks CGA because of the increasing CGA because of the increasing survival of the ELBW infant.survival of the ELBW infant.

Definition Old vs. New BPDDefinition Old vs. New BPD

IncidenceIncidence

A review of A review of Surfactant trials Surfactant trials demonstrated a demonstrated a significant significant differences in differences in incidence incidence depending on the depending on the institution and institution and definition used (17-definition used (17-57%).57%).

IncidenceIncidence

The incidence however changes The incidence however changes dramatically with BW/GA increasing dramatically with BW/GA increasing from @7% in the 1001-1250 gm BW from @7% in the 1001-1250 gm BW infant to @64% in the 501-750 gm infant to @64% in the 501-750 gm BW infant.BW infant.

Risk FactorsRisk Factors

Major risk factorsMajor risk factors PrematurityPrematurity Genetic predisposition Genetic predisposition

(male, white, family history of (male, white, family history of atopy and asthma, HLA-A2)atopy and asthma, HLA-A2)

Fluid overloadFluid overload Patent ductus Patent ductus

arteriosusarteriosus InfectionInfection InflammationInflammation Air leakAir leak Mechanical ventilationMechanical ventilation OxygenOxygen Malnutrition Malnutrition

PathophysiologyPathophysiology

BPD is a BPD is a mutifactorial mutifactorial disorder beginning disorder beginning with an acute lung with an acute lung injury in a injury in a susceptible host susceptible host followed by followed by continued injury continued injury and abnormal and abnormal repair.repair.


Lung injury can occur as a result of Lung injury can occur as a result of any of the following.any of the following.


Surfactant deficiencySurfactant deficiencyResults in collapse of sacculesResults in collapse of sacculesDistention of distal alveolar ductsDistention of distal alveolar ductsMaldistribution of ventilationMaldistribution of ventilation


Pulmonary EdemaPulmonary EdemaAlmost always present in RDSAlmost always present in RDSWorsened by hypoproteinemia and Worsened by hypoproteinemia and

increased pulmonary blood flow (think increased pulmonary blood flow (think PDA)PDA)


Oxygen ExposureOxygen ExposureProlonged exposure to high [ ] can lead Prolonged exposure to high [ ] can lead

to epithelial and endothelial cell to epithelial and endothelial cell damage, cilliary dysfunction, decreased damage, cilliary dysfunction, decreased lung lymph flow, altered surfactant lung lymph flow, altered surfactant synthesis, and inhibition of lung growthsynthesis, and inhibition of lung growth


Oxygen Free RadicalsOxygen Free RadicalsInadequate concentrations of Inadequate concentrations of

antioxidants may predispose the antioxidants may predispose the premature infant to cell membrane premature infant to cell membrane destruction and the unraveling of destruction and the unraveling of nucleic acidsnucleic acids


Mechanical VentilationMechanical VentilationVolutrauma (Thought to provoke a Volutrauma (Thought to provoke a

complex inflammatory cascade that complex inflammatory cascade that ultimately leads to BPD)ultimately leads to BPD)

Barotrauma (Increased pressure is Barotrauma (Increased pressure is transmitted to terminal bronchioles and transmitted to terminal bronchioles and alveolar ducts, dissects into the alveolar ducts, dissects into the interstitium where it is trapped, interstitium where it is trapped, resulting in PIE)resulting in PIE)


Mechanical VentilationMechanical VentilationHow many breaths do you deliver to a How many breaths do you deliver to a

newborn infant at a rate of 30 bpm? newborn infant at a rate of 30 bpm? (commonly seen in the NICU…)(commonly seen in the NICU…)


Mechanical VentilationMechanical Ventilation43,20043,200


Mechanical VentilationMechanical VentilationImportant to note that there is ample Important to note that there is ample

evidence demonstrating that excessive evidence demonstrating that excessive airway pressures associated with large airway pressures associated with large tidal volumes can trigger the tidal volumes can trigger the inflammatory cascade in the lungs – the inflammatory cascade in the lungs – the overdistention of the lungs induces overdistention of the lungs induces increased pulmonary vascular resistance increased pulmonary vascular resistance with retention of neutrophils and release with retention of neutrophils and release of inflammatory mediatorsof inflammatory mediators


InfectionInfectionOften seen following the “honeymoon” Often seen following the “honeymoon”

period (the several days after period (the several days after exogenous surfactant treatment when exogenous surfactant treatment when often minimal or no oxygen often minimal or no oxygen supplementation is neededsupplementation is needed

Increased risk of BPD seen in babies of Increased risk of BPD seen in babies of mothers who have chorioamnionitismothers who have chorioamnionitis


InfectionInfectionNeutrophils, macrophages, leukotrienes, Neutrophils, macrophages, leukotrienes,

platelet-activating factor, interleukin-6, platelet-activating factor, interleukin-6, interleukin-8, and tumor necrosis factor interleukin-8, and tumor necrosis factor have all been found in high have all been found in high concentrations in infant who developed concentrations in infant who developed BPDBPD


InfectionInfectionInconsistent reports that colonization Inconsistent reports that colonization

with Ureaplasma urealyticum may with Ureaplasma urealyticum may predispose and infant to BPDpredispose and infant to BPD


InflammationInflammationThe inflammatory process begins with The inflammatory process begins with

an initial stimulus, (oxygen free radicals, an initial stimulus, (oxygen free radicals, pulmonary barotrauma, infectious pulmonary barotrauma, infectious agents, etc…) and progresses with agents, etc…) and progresses with leukocyte infiltration and a cascade of leukocyte infiltration and a cascade of destruction and abnormal repair – destruction and abnormal repair – leading to the development of chronic leading to the development of chronic lung disease lung disease


NutritionNutritionThe sick premature infant has an The sick premature infant has an

increased nutritional requirement increased nutritional requirement because of increased metabolic needs because of increased metabolic needs and rapid growth requirements – if the and rapid growth requirements – if the needs are not met the infant will needs are not met the infant will develop a catabolic state, probably a develop a catabolic state, probably a major contributing factor in the major contributing factor in the pathogenesis of BPDpathogenesis of BPD

Pathologic ChangesPathologic Changes

Early changes Early changes include areas of include areas of altelectasis filled altelectasis filled with proteinacious with proteinacious fluid alternating fluid alternating with areas of with areas of overexpansionoverexpansion


Continued airway Continued airway injury is seen as a injury is seen as a loss of epithelium loss of epithelium and ciliaand cilia


Late findings Late findings include interstitial include interstitial fibrosis, cystic fibrosis, cystic dilatation, dilatation, atelectasis, atelectasis, intersitial edema, intersitial edema, and lymphatic and lymphatic distentiondistention

DiagnosisDiagnosis

BPD is BPD is predominately a predominately a disorder of the disorder of the surviving surviving extremely extremely premature infant, premature infant, although it can be although it can be seen in the term seen in the term infant with infant with respiratory failure.respiratory failure.

DiagnosisDiagnosis

Often preceded by significant oxygen Often preceded by significant oxygen requirements and need for requirements and need for mechanical ventilation beyond the mechanical ventilation beyond the first week of life.first week of life.

DiagnosisDiagnosis

Physical ExaminationPhysical ExaminationWorsening respiratory status manifested Worsening respiratory status manifested

by increased WOB, increased Oby increased WOB, increased O22 requirement, increased incidence of requirement, increased incidence of apnea-bradycardiaapnea-bradycardia

Retractions, diffuse rales, prolonged Retractions, diffuse rales, prolonged expirationsexpirations

Possible RV heave, single SPossible RV heave, single S22, or , or prominent Pprominent P22, signifying cor pulmonale, signifying cor pulmonale

DiagnosisDiagnosis

Physical ExaminationPhysical ExaminationEnlarged liver secondary to right heart Enlarged liver secondary to right heart

failure, or displacement secondary to failure, or displacement secondary to hyperinflationhyperinflation

DiagnosisDiagnosis

Laboratory and Radiographic StudiesLaboratory and Radiographic StudiesABG may reveal CO2 retention (although ABG may reveal CO2 retention (although

pH is often normal with chronic lung pH is often normal with chronic lung disease - disease - ))

Abnormalities in the electrolytes may be Abnormalities in the electrolytes may be the result of the retained CO2 (elevated the result of the retained CO2 (elevated bicarbonate), diuretic therapy (hypo-Na, bicarbonate), diuretic therapy (hypo-Na, hypo-K, and hypo-Cl), and fluid hypo-K, and hypo-Cl), and fluid restriction (elevated BUN & Cr) restriction (elevated BUN & Cr)

DiagnosisDiagnosis

Laboratory and Radiographic StudiesLaboratory and Radiographic StudiesChest X-ray can be quite variable from Chest X-ray can be quite variable from

diffuse haziness and hypoinflation to diffuse haziness and hypoinflation to streaky interstitial markings, streaky interstitial markings, altelectasis, cysts, and hyperinflationaltelectasis, cysts, and hyperinflation

ManagementManagement

The management The management of BPD includes the of BPD includes the preventive preventive measures to measures to decrease the decrease the incidence of the incidence of the disease and disease and treatment treatment modalities once it modalities once it is presentis present


PreventionPreventionDecrease the risk of prematurityDecrease the risk of prematurityDecrease risk factorsDecrease risk factors

PrematurityPrematurity Genetic predispositionGenetic predisposition Fluid overloadFluid overload Patent ductus arteriosusPatent ductus arteriosus InfectionInfection InflammationInflammation Air leakAir leak Mechanical ventilationMechanical ventilation OxygenOxygen Malnutrition Malnutrition


PreventionPreventionVitamin A supplementation?Vitamin A supplementation?


TreatmentTreatmentPrudent oxygen supplementation Prudent oxygen supplementation

(premature infants <36wks O(premature infants <36wks O22 Sat 88- Sat 88-94% & >36wks O94% & >36wks O22 sat >95%) sat >95%)

Softer mechanical ventilation strategies Softer mechanical ventilation strategies (NCPAP vs. NSIMV)(NCPAP vs. NSIMV)

Fluid restriction +/- diureticsFluid restriction +/- diuretics


TreatmentTreatmentBeta-2 agonist for acute exacerbations Beta-2 agonist for acute exacerbations

of CLDof CLDNutritionNutrition

PrognosisPrognosis

Depends on the Depends on the degree of degree of pulmonary disease pulmonary disease and the presence and the presence of other medical of other medical conditionsconditions

PrognosisPrognosis

Pulmonary outcomePulmonary outcomeAlthough there is a significant risk of Although there is a significant risk of

needing rehospitalization within the first needing rehospitalization within the first year (@30%) and many infant with BPD year (@30%) and many infant with BPD have increased airway resistance and have increased airway resistance and reactivity, the pulmonary outcome is reactivity, the pulmonary outcome is goodgood

PrognosisPrognosis

Neurodevelopmental outcomeNeurodevelopmental outcomeChildren with BPD increased risk for Children with BPD increased risk for

adverse outcome compared to infants adverse outcome compared to infants without BPDwithout BPDIncreased hearing impairmentIncreased hearing impairmentIncreased ROPIncreased ROPIncreased incidence of learning disabilities, Increased incidence of learning disabilities,

ADHD, and behavioral problemsADHD, and behavioral problems

What’s the Evidence for What’s the Evidence for how we Treat BPD?how we Treat BPD?

BronchodialatorsBronchodialators

Cromolyn SodiumCromolyn Sodium

Early Inhaled SteroidsEarly Inhaled Steroids

Early Inhaled SteroidsEarly Inhaled Steroids

No increased No increased incidence of:incidence of: InfectionInfection HyperglycemiaHyperglycemia HypertensionHypertension GI bleedingGI bleeding CataractsCataracts

IVHIVH PVLPVL NECNEC ROPROP PDAPDA

Early Post-natal (<96hrs) SteroidsEarly Post-natal (<96hrs) Steroids

Early Post-natal (<96hrs) SteroidsEarly Post-natal (<96hrs) Steroids

IncreasedIncreased HyperglycemiaHyperglycemia HypertensionHypertension Growth FailureGrowth Failure GI BleedingGI Bleeding Intestinal PerforationIntestinal Perforation Baley PDI <70 in tested Baley PDI <70 in tested

survivorssurvivors Abnormal Neuro examAbnormal Neuro exam Developmental DelayDevelopmental Delay Cerebral PalsyCerebral Palsy

No changeNo change InfectionInfection Severe IVHSevere IVH NECNEC Pulmonary HemorrhagePulmonary Hemorrhage PVLPVL ROPROP EEGEEG Blindness & DeafnessBlindness & Deafness

DecreasedDecreased Pulmonary Air LeakPulmonary Air Leak PDAPDA

SurfactantSurfactant

Vitamin AVitamin A

Which of the following CXR findings are consistent Which of the following CXR findings are consistent with stage 4 of BPD?with stage 4 of BPD?

A)A) lung appears cystic with areas of hyperinflation lung appears cystic with areas of hyperinflation & areas of atelectasis& areas of atelectasis

B)B) fibrosis and edema with areas of consolidation fibrosis and edema with areas of consolidation & areas of overinflation& areas of overinflation

C)C) low volumes with diffuse fine granular opacitieslow volumes with diffuse fine granular opacities

D)D) opaque lung fields with air bronchograms & opaque lung fields with air bronchograms & possibly interstitial airpossibly interstitial air

E)E) normalnormal

Which of the following organisms have been Which of the following organisms have been implicated in the pathogenesis of BPD?implicated in the pathogenesis of BPD?

A)A) MycoplasmaMycoplasma

B)B) UreaplasmaUreaplasma

C)C) Group B strepGroup B strep

D)D) Borrelia burgdorferiBorrelia burgdorferi

E)E) Moraxella catarrhalisMoraxella catarrhalis

Which statement about long term survivors with Which statement about long term survivors with BPD (school-age) is true?BPD (school-age) is true?

A)A) They have an increased incidence of asthma.They have an increased incidence of asthma.

B)B) They have airway hyper-responsiveness.They have airway hyper-responsiveness.

C)C) They have an increased incidence of atopy.They have an increased incidence of atopy.

D)D) They have an increased incidence of hospital They have an increased incidence of hospital admissions.admissions.

Which of the following treatments for Chronic Which of the following treatments for Chronic Lung Disease has been shown to improve the Lung Disease has been shown to improve the long term outcome of this population (Need long term outcome of this population (Need for ventilatory support, length of hospital for ventilatory support, length of hospital stay, long term neurodevelopmental stay, long term neurodevelopmental outcome)? outcome)?

A)A) BronchodilatorsBronchodilators

B)B) Thiazide DiureticsThiazide Diuretics

C)C) Loop DiureticsLoop Diuretics

D)D) Inhaled CorticosteroidsInhaled Corticosteroids

E)E) None of the aboveNone of the above

Which of the following is NOT a risk factor for Which of the following is NOT a risk factor for bronchopulmonary dysplasia?bronchopulmonary dysplasia?

A.A. PrematurityPrematurity

B.B. Female sexFemale sex

C.C. Patent ductus arteriosusPatent ductus arteriosus

D.D. Air leakAir leak

E.E. Mechanical ventilationMechanical ventilation

How many breaths are delivered via positive How many breaths are delivered via positive pressure to an infant on SIMV at a rate of 30 per pressure to an infant on SIMV at a rate of 30 per day?day?

A)A) 432432

B)B) 4,3204,320

C)C) 43,20043,200

D)D) 432,000432,000

E)E) 4,320,0004,320,000

F)F) 4.32 x 104.32 x 1077

G)G) 4.32 x 104.32 x 1088

H)H) 4.32 x 104.32 x 1099

bpd

Health & Medicine

pathophysiology bpd

pathophysiology lung

diagnosis bpd

increased risk of bpd

anewborn infant

elbw infant

thepathogenesis of bpd

new bpd