Pulmonary Flashcards
1
Q
Lung and Airway Development
A
- Derived from Endoderm
- Lung forms from ventral bud of esophagus
- Lung development dependent on : Fetal lung fluid, fetal breathing, peristalsis of airway
2
Q
Lung Vascular Supply
A
- Arise from branches of 6 aortic a.
- Pre-acinar a.: adjacent to airways up to and including non resp bronchioles, developed by angiogenesis (from pre existing vessels); complete by 16 w
- Intra-acinar a: Adjacent to resp bronchioles and alveolar ducts; develop by vasculogenesis (de novo from mesoderm); growth continues until 8-10 y old
3
Q
Development of Small Pulm Arteries
A
- Fetus: Proximal a. have completely encircling sm. muscle layer that changes to incomplete muscularization until distally disappears completely (intra acinar a. lack muscle)
- Near - Term: Half of resp bronchiolar vessels are muscularized or partially muscularized; intra acinar a. continue to lack
- 4-6 w.: Involution of medial sm. muscle layer and reduction in muscular wall thickness
- Adult: Extension of muscularization to include acinar arteries as well - only a thin layer of sm muscle
4
Q
Alveolarization
A
- Continue development until 3-8 y.
- 50-150 million at term increasing to 200-600 million in adult
- Enhanced by: Vit A and thyroxine
- Delayed by: Postnatal Steroids, O2, nutritional deficiencies, Mechanical Vent, Insulin, Inflammation
5
Q
Lung Development Stages
A
- Embryonic (0-5 w): Lung forms from ventral bud of Esophagus; bronchi established; 5 lobes of lung; pulm vasculature develops
- Pseudoglandular (5-15w): Continued branching, all large airway up to term bronchiole, AF production begins, pneumocyte precursors develop, vasculature of a and v, separation of thorax and peritoneal cavity
- Canalicular (15-25w): Canaliculi branch out of terminal bronchioles, prelim gas exchange, T II pneumocytes →T I
- Saccular (25-35w): Multiple sacs form from terminal bronchioles, gas exchange via alveolar-capillary membrane
- Alveolar and Vasculature (36+w- 8 y): Alveoli form from terminal sacs, alveoli increase in diameter, microvascular growth and maturation
6
Q
Lung Stage Development-Specific Abnormalities
A
- Embryonic - BLTT: Bronchogenic Cysts, Laryngeal Cleft, Tracheal Stenosis, TEF
- Pseudoglandular - BCCCP: Branching Abnormalities, CDH, CLE, CPAM, Pulmonary lymphangiectasia,
- Canalicular - PSA: Pulm Hypoplasia, Surfactant Deficiency, Alveolar Capillary Dysplasia
- Saccular - PS: Pulm Hypoplasia, Surfactant Deficiency
- Alveolar - CPS: CLE, Pulm Hypertension, Surfactant Deficiency
7
Q
TI v TII Pneumocyte
A
- Fried Egg Shape, Tight Jxn, thin and cover 90% surface but fewer # cells, GAS EXCHANGE, derived from TII
- Cuboidal shape, cover 10% surface but greater # cells, SURFACTANT Metab and secretion, Progenitor to TI
8
Q
Fetal Lung Fluid
A
- During respiration, larynx opening allows minimal but steady FLF flow out that is swallowed or mixed with AF; larynx closure maintains distending pressure on lungs
- FLF maintains airway volume similar to FRC at birth 20-30 mL/kg
- Near term FLF production decreases to 4-5 mL/kg/h
- FLF production inhibited by Epinephrine and β agonists
- Prior to birth, resp epithelium changes from Cl secreting to Na absorbing membrane
9
Q
FLF Clearance
A
- PRENATAL: ↓ Formation FLF, ↓Cl secretion concurrently with ↑ Na transport, ↑Lymph oncotic pressure and ↓ fetal alveolar protein →fluid movement to lymphatics
- LABOR: Mechanical Forces, Catecholamine surge ↑ Na transport, ↑ Cortisol and Tyroid Hormones that ↑ Na transport
- POSTNATAL (35% to still be cleared): Lung distension ↑ transpulmonary pressures, ↑Lymph oncotic pressure and ↓ fetal alveolar protein →fluid movement to lymphatics
10
Q
Surfactant Composition
A
- 50% DPPC, 20% PC, 8% PG, 8% Surf Protein A, B, C,D, 8% Neutral Lipids
11
Q
Surfactant Protein Origin (Made in ER and glycosylated in Golgi Bodies)
A
A. TII, Clara Cells, Chr 10, expressed 3rd tri
B. TII, Clara Cells, Chr 2, expressed end of 1st tri
C. TII, Chr 8, expressed end of 1st tri
D. TII, Nonpulm Cells, Chr 10, expressed last - 3rd tri
12
Q
Surfactant Protein Characteristics
A
A. 28, 32 kDA, MOST ABUNDANT (~50%), induced by steroids, Hydrophilic, Collectin Member
B. 8 kDA, Hydrophobic, induced by steroids
C. 4 kDA, Hydrophobic, induced by steroids
D. 43 kDA, induced by steroids, Hydrophilic, Collectin Member
13
Q
SP-A
A
- Assists with tubular myelin formation (w/ SP-B and Ca)
- Enhances phospholipid uptake and inhibits phospholipid secretion
- Place role in host defense: role in opsonization, phagocytosis, agglutination, reduction of viral infectivity, modulation of inflammation
SP-A Null: ↑ inflammation, ineffective pulm clearance, no tubular myelin
SP-A Deficient: ↑ RDS severity and CLD development
14
Q
SP-B
A
- Critical for SURFACTANT Function
- Assists with tubular myelin formation (w/ SP-A and Ca)
- Promotes surface adsorption of phospholipids (w/ SP-C)
SP-B homozygote deficiency: Severe resp failure soon after birth, require lung transplant, AR inheritance
SP-B Partial Deficiency: CILD in childhood
15
Q
SP-C
A
- Critical for SURFACTANT Function
- Promotes surface adsorption of phospholipids (w/ SP-B)
SP-C Null: Minimal Effect
SP-C Deficient: ILD at a few mo of age ranging from mild symptoms to requiring lung transplant, AD or sporadic inheritance
16
Q
SP-D
A
- Place role in host defense: role in agglutination, reduction of viral infectivity, also involved in opsonization and modulation of inflammation
- Anti-oxidant
- Surfactant lipid homeostasis
SP-D null: altered surfactant homeostasis, susceptible to viral pathogens
SP-D Deficiency: No association
17
Q
ATP-Binding Cassette Member A3 Deficiency
A
- Most common genetic cause of surfactant deficiency
- AR Inheritance
- lack DPPC and PG, ↓ Lamellar bodies
- term infant with resp distress soon after birth, may present later with FTT, clubbing and ILD
18
Q
Surfactant Protein and Secretion
A
- TRANSPORT: SP-B & SP-C with surfactant lipids transported to multivesicular bodies
- LAMELLAR STORAGE
- SECRETION: SP-B & SP-C with surfactant lipids secreted into alveolar subphase and interact with SP-A to form tubular myelin reservoir
- ADSORPTION: Tubular myelin multi layers form a film and reduce surface tension at air-liquid interface
- TURNOVER: Endocytosis takes remnants by TII cells
- RECYCLING: Recycled into multivesicular and lamellar bodies; 95% secreted surfactant is recycled with 10 h turnover time
- CLEARANCE: Alveolar Macrophages clear and catabolize remnants
19
Q
Accelerate Lung Maturation
A
- Pregnancy: cHTN, CV Dz, Placental Infarct, IUGR, PIH, PROM, Incompetent Cervix, Hemoglobinopathy, Chorio (yet higher CLD incidence)
- Other: Steroids, TH, TSH, TRH, cAMP, Methylxanthines, β agonists, Prolactin, Estrogens, Epidermal GF, Transforming GF α
20
Q
Delayed Lung Maturation
A
- Pregnancy: DM, Rh Isoimmun w/ hydrops, 2nd born twin, Male, C/s, Prematurity
- Other: Insulin, Androgens, Transforming GF β
21
Q
Immature V Mature Lung Surfactant Changes
A
- Immature: Large # glycogen lakes & Few Lamellar Bodies, Saturated PC/Total PD = 0.6, Low PG, 10% PI, Low SP-A
- Mature: No glycogen lakes & Many Lamellar Bodies, Saturated PC/Total PD = 0.7, 10% PG, 2% PI, 5% SP-A
22
Q
Surfactant Component Changes during Development
A
- PI present before PG, increases until ~35 w then falls
- L/S increases with GA, sharply at ~ 35 w ; sphingomyelin decreases after 32 w; L/S = 2 at 35 w
- PG increases at 34-35w, not present in infants with RDS; certain bacteria produce PG leading to False +, not necessary for surfactant function
23
Q
Fetal Lung Maturity Testing
A
L/S >2.0 = RDS <0.5%
L/S<1.0 = RDS 100%
PG present = RDS <0.5%
L/S >2.0, no PG = RDS >80 %
L/S >2.0, + PG = RDS 0 %
L/S >2.0, +DM or Rh Iso = RDS 13 %
Foam Test : AF+ethanol→Foam = Mature lung
Lamellar Body Solubilization Test: Unraveling or solubilization of lamellar bodies in mature lung
AF Appearance: Measure OD 650 nm of AF
24
Q
Natural Surfactant - all contain DPPC and SP-B & C
A
Survanta/Beractant: Minced Bovine lung
Infasurf/Calfactant: Bovine lung lavage, most SP-B
Curosurf/Porctant Alpha :Minced Porcine lung
Alveofact/Bovactant: Bovine lung lavage
25
Synthetic Surfactant - all DPPC
Exosurf: Synthetic lipids mixture, Hexadecanol, tyloxapol, no SP
ALEC: PG, no SP
Surfaxin: DOPG, SP-B
26
LAPLACE's Law
P=2T/r
1. ↓ alveolus size = ↑ surf conc → ↓ Surface Tension further preventing air from leaving
2. ↑ alveolus size = thinly spread surf and less conc → ↑ Surface Tension and lung recoil pressure
3. As lung INflates, Surface Tension INcreases and as it DEflates, Surface Tension DEcreases
4. Decreased Tension INCREASES Compliance
5. Decreases Tension prevents transudation of fluid from capillaries into alveoli
27
↓ PVR during extrauterine Pulm Transition
1. Lung inflation activating stretch receptors leading to Pulmonary Vasodilation
2. Gas Exchange leading to ↑O2 resulting in Pulmonary Vasodilation
3. Vasoactive mediators (NO, endothelin-1)
28
Factors leading to Delayed Fluid Resorption
1. Maternal: Excessive analgesia, excessive maternal IV fluids
2. Delivery: C/s, breech, DCC
3. Fetal/Infant: perinatal depression, polycythemia, Inadequate Epi surge
29
Factors leading to Failure of ↓ PVR
1. Airway obstruction and atelectasis → lack of oxygenation, minimal alveolar ventilation
2. Inflammatory Conditions (PNA, Sepsis) → ↑ leukotrienes, thromboxane, PAF
3. Pulm Hypoplasia (CDH) → abnormal pulm vasculature
4. Defects of PG or NO synthesis
5. Maternal Meds (Indomethacin, Aspirin)
30
Boyle's Law
P1V1=P2V2
31
Control of Breathing
Inspiration: Insp muscles of Chest and diaphragm contract causing thorax expansion and greater neg intrapleural pressure that causes intra alveolar pressure to ↓ with corresponding ↑ in alveolar volume. As barometric pressure > alveolar pressure, air moves into lungs.
Expiration: Resp muscles relax. Lung recoil pressure results in positive alveolar pressure (intra pleural pressure approaches baseline) resulting in gas leaving lungs
32
Hering-Breuer Inflationary Reflex
Prevents overinflation
Pulm stretch receptors send afferent neural input to medulla causing vagal nerve to inhibit further inspiration and/or promote expiration limiting i time.
With associated ↑ e time, resp frequency ↓ = apnea potential
Progressive ↑ in reflex as lung volume ↑ above FRC
Reflex ↑ with GA, strongest in first few mo after birth and weak in adults
33
Hering-Breuer Deflation Reflex
Reacts to abrupt deflation
↑ RR with abrupt delation, assoc with periodic deep breaths ('sighs') to prevent atelectasis
Important to maintain FRC in setting of compliant chest wall and large lung recoil
34
Paradoxical Reflex of Head
Inhibits Hering-Breuer reflex and extends inspiration
Important in first few breaths after delivery to inflate fluid filled lungs
Causes 'sigh" breaths that reverse lung preference to collapse during quiet breathing
35
Control of Respiration
1. CSF: ↑ in H+ (most sens!), ↑ in paCO2 act on central chemoreceptors in medulla
2. Blood: ↓ in paO2 (most sens!), ↑ in paCO2, H+ acting on peripheral chemoreceptos on carotid and aortic bodies
36
Response to CO2 Δ
1. CO2 Δ dependent on CHEMORECEPTORS on ventrolateral surface of MEDULLA that sense H+ ion conc of ECF
2. ↑ in paCO2 leads to ↑ in H+ ion conc and ↑ in RR
3. Sensitivity to chemoreceptors is reduced in preterm infants and increases with GA
Minute Ventilation x Alveolar PCO2 graph
37
Response of Ventilation to O2 Δ
1. Response to O2 is mediated by PERIPHERAL CHEMORECEPTORS in CAROTID AND AORTIC BODIES
2. Response to hypoxemia includes hyperpnea and initial ↑ in ventilation followed by ↓ in ventilation; in preterm infant response is not hyperpnea but rather resp depression attributable to poor peripheral chemoreceptors
Minute Ventilation x Alveolar pCO2 graph
38
Lung Perfusion Zones
I. PA>Pa>Pv; uppermost part of lung, PaPA>Pv: Blood flow dependent on arterial-alveolar pressure difference
III. Pa>Pv>PA; Blood flow dependent on arterial-venous pressure differences; NEONATAL LUNG FXN AS ZONE III
IV. Pa>Pv; blood flow decreased may be due to excessive intravascular pressure leading to interstitial edema and alveolar capillary collapse; ↑ ECF (PDA, fluid overload, leaky capillaries) = shift to Zone IV with ↑ PVR and ↓ blood flow
39
Resistance = ∆ Pressure/∆ Flow
Total R = Chest Wall R (25%) + Airway R (55%) + Lung Tissue R (20%)
Total R = 40-55 cm H20/L/Sec
40
Airway Resistance
1. 50% due to nasal resistance
2. Airways dilate during inspiration, ↓ R; less tethering during expiration ↑ R
3. Laminar Flow (small airways): Air travels in straight lines with faster molecules in center; Flow =(∆Pressure x π x radius^4) /(8 length x viscosity)
4. Turbulent Flow (large airways and at branching): R∞ (Length x density)/(radius^5); affected by density
41
Lung Tissue Resistance
1. Due to friction between tissues of lung and CW
2. ↑ in neonates due to ↑ tissues density
42
TLC
TLC (50-60 mL/kg) = VC + RV
TLC = IC + FRC (20-30 mL/kg)
IC = IRV +TV (5-7 mL/kg)
FRC = ERV + RV
43
Compliance
∆ Volume/∆ Pressure
44
Elastance
∆ Pressure/∆Volume
45
Power
Work (kg cm) x Frequency (per min)
46
Volume Pressure Curves
1. Loop A: disease with low FRC like RDS or atelectasis; ↓ Compliance
2. Normal Lung, Normal FRC
3. Loop C: disease with high FRC like MAS, CLD, excessive vent pressures, ↓Compliance but at higher volumes
47
Flow Volume Loops
Volume on X axis with Expiration over Inspiration and Flow on Y axis
1. Normal: Shark Fin
2. Restrictive: Cut fin
3. Obstructive (CLD): Scalloped and widened
4. Extrathoracic upper airway obstruction (vocal cord paralysis, laryngomalacia) = Expiration ok: Flattened Inspiratory phase
5. Intrathoracic upper airway obstruction (tracheomalacia, vascular rings) = Inspiration ok: Flattened expiratory phase
6. Fixed upper airway obstruction (tracheal stenosis): Flattened inspiratory and expiratory phases
48
Time Constant
- Measures how quickly lung empties
= Resistance (P/flow) X Compliance (V/P)
- flow = V/time
1TC=63%
2TC=86%
3TC=95%
3-5 TC necessary for adequate insp and exp
Healthy Newborn Resistance = 30 cm H2O/L/sec and compliance = 0.003-0.005 L/cm H20
49
Time Constant with Disease
Lung Compliance (mL/cm H20): Healthy Term (3-5), RDS (0.5-1), CLD (<1)
Resistance (cm H20/L/sec): Healthy Term (20-40), RDS (>40), CLD (>150)
TC: Healthy Term (0.09-0.15 s), RDS (0.05 s), CLD (0.15 s)
50
Resp Mechanics: Neonate v Adult
↑ Neonates: RR, RV, MV (TV x RR), Alveolar Vent [(TV - dead space) x RR], CW compliance, Lung tissue resistance, O2 consumption
↓ Neonates: TV, TLC, IC, VC, TC, Lung Compliance, Muscle strength and endurance
Similar: Dead space, FRC
51
paO2
- partial pressure of O2 in plasma of arterial blood
- Measures randomly dissolved O2 (free O2)
- determined by alveolar pO2 and is INDEPENDENT of Hgb available to bind to dissolved O2
- Reduced in the following: V/Q mismatch, reduced alveolar vent, diffusion block, R--> L shunt
52
O2 sat
- Heme sites bound to O2 molecules
- Affected by conditions that shift the oxygen dissociation curve
53
O2 Content
- measured in mL O2/dL
= O2 bound to Hb [(1.34 mL O2/g Hb) x Hb (g/dL) x O2 sat] + dissolved O2 [(0.003 x pa O2)]
54
Effect on paO2, O2 sat and O2 content in diff states
1. Severe Anemia ( -, -, ↓)
2. Severe V/Q mismatch (↓, ↓, ↓)
3. CO poisoning ( -, ↓, ↓)
4. High Altitude (↓, ↓, ↓)
55
A-a Gradient
- transferrence of Oxygen from atmosphere to pulm circulation; larger the gradient the poorer the O2 transfer
- ↑ with higher FiO2; 10-15 in RA & 80-100 if FiO2 1.0
- If >600 with FiO2 1.0 for 8-12 h consider ECMO
pAO2 - paO2 = [FiO2 x (pB-pH20)] - paCO2/R - paO2
55
Altitude effect on paO2
(pB#1 - pH20) x FiO2#1 = (pB#2 - pH20) x FiO2#2
55
Impact of Disease on A-a Gradient
- Gradient in RA ↑ with V/Q minsmatch
- Gradient in 1.0 ↑ with shunting
- Oxygen is perfusion limited while CO2 is diffusion limited
55
O2 Delivery
= CO x O2 content
= CO x {[1.34 x Hb x O2 sat] + [0.003 x paO2]}
- CO in dL/min, O2 content in O2/dL
- If there is a low CO, low Hb or low O2 sat, O2 delivery will be inadequate
56
Oxygen Consumption
- difference in O2 delivered to tissues and O2 returning from tissues
VO2= [CO (dL/min) x 1.34 (mL/g Hb) x Hb (g/dL)] x [arterial O2 sat- venous O2 sat}
- If VO2 is ↓ (lung dz, ↓O2, ↓ tissue perfusion) tissues try to maintain O2 levels by
1. ↑ O2 extraction which is limited because gradient necessary for diffusion
2. Recruiting more capillaries for ↑ O2 delivery; however if amount of O2 delivered reaches critical level, cells can become anoxic and change from aerobic to anaerobic metab
56
Oxyhemoglobin Dissociation Curve
1. Shift Right (↑ CO2, acidosis, DPG, exercise, temp) = ↑ release of O2 to tissues
2. Shift Left = Higher affinity for O2 (fetal Hb - similar to adult at 4-6 mo of age & CO)
Sat = y axis, paO2 = x axis
56
States of Increased O2 consumption
1. ↑ Caloric intake
2. ↓ Body temperature
3. Neonate >> adult (6-8 vs 3.2 mL/kg/min)
4. Term>Preterm
5. AGA>SGA
57
CO2 Transport
1. Total CO2 = dissolved CO2 +HCO3- + carbamino compounds
Dissolved CO2 = 10% CO2 & ↑ linearly with ↑ in pCO2; 20 x more soluble that O2
Bicarb = 70% CO2; RBC contain carbonic anhydrase and contribute to HCO3 production
Carbamino: 20% total CO2; CO2 can reversibly bind to non-ionized amino groups - majority in Hb
Dissociation Curve
58
Bohr Effect
= ∆ in O2 bound to Hb based on response to pCO2
At tissues: CO2 produced by tissues enters adjacent circulation leading to ↑ pCO2 causing O2 to have decreased affinity
59
Haldane Effect
= ∆ in CO2 bound to Hb based on response to O2
60
Henderson Hasselbach
Hydrogen conc = (24 x pCO2)/Bicarb
61
CO2 Elimination
Dependent on:
1. Alveolar minute ventilation (dependent on lung resistance, compliance and Tc)
2. Diffusion across alveolar capillary membrane
3. Matching of alveolar ventilation with pulmonary blood flow
62
Abnormal Hb Binding
1. Carboxyhemoglobinemia: CO binds better to heme than O2 and increases bound O2 affinity affecting delivery to tissues
- falsely elevates O2 saturation
- crosses placenta
2. Methemoglobinemia: Ferrous (reduced) changes to ferric (oxidized) state decreasing ability to bind to O2
- normal paO2 but ↓ O2 sat
- arterial brown blood
- Tx:methylene blue
63
↑ MAP
↑ PEEP > ↑ PIP > ↑ I time
MAP = k (PIP - PEEP) x { I time/(I time - E time)} + PEEP
64
OI
OI = (MAP x FiO2)/postductal paO2 x 100
65
HJV v HFOV
1. high velocity gas source with interrupter for inspiration and expiration V delivery by vibrating pistons connected to continuous flow
2. PASSIVE expiration v ACTIVE expiration
3. Requires more time to get gas out of lungs v more time to get air into lungs
4. Frequency is 4-11 Hz v 3-15 Hz
5. Adjustable iTime v fixed
6. Sigh breaths v No sigh
7. TV independent of frequency v indirectly proportional to frequency
66
ECMO (VV v VA)
1. Catheter R jugular into RA & catheter angled across tricuspid v Catheter R jugular into RA & R carotid to aortic arch
2. achievable paO2: lower v higher
3. Perfusion Rates: Requires higher v requires lower
4. Pulmonary circulation: Maintains v bypasses
5. Cardiac support: Not provided v provided
6. Benefits: spares carotid, ↓ arterial emboli v resp & cardiac support
67
ECMO Criteria
1. Failing vent support with FiO2 1.0, PIP > 35, paO2<40
2. A-a gradient>600 while receiving 100% FiO2 for 8-12 h
3. OI>40
4. PaO2 < 30 -40
68
ECMO Contraindications
1. GA <34 w (↑IVH risk)
2. Severe IVH
3. Sig Coaguloapathy
4. Irreversible lung dz
5. Irreversible neuro
6. Congenital Anomalies
69
Resp Disease Clinical findings
1. Bell Shaped Thorax: Pulm hypoplasia or NM Disorders
2. Barrel Shaped Chest: PTX, CDH, cystic lung dz
3. Scaphoid Abdomen: CDH
4. Umbilicus shift: towards affected side of unilateral diaphragmatic paralysis
70
RDS
- ↓ lung compliance
- unstable alveoli
- ↓FRC with atelectatic alveoli and low lung volumes
- Shunting of blood past atelectatic areas leading to hypoxemia and hypercapnia
- Alveoli filled with transudate
RF: low GA, MDM, male, perinatal depression
71
TTN
- 48 - 72 h
- RF: c/s, MDM, Maternal sedation, precip delivery, perinatal depression
- tachypnea with normal MV as lower TV from shallow breathing
72
PNA
Early: GBS, E Coli, Klebsiella, Listeria
Late: Above + S Aureus, Pseudomonas, Fungal, Chlamydia
Other: CMV, Viral, Syphilis
RF: PROM>24 h, gasping due to asphyxia
73
BPD Prevention
1. Vitamin A
2. Caffeine
- Corticosteroids? Early CPAP? SOD?
74
Pulm Hemorrhage
- resulting from acute increase in cap hydrostatic pressure (L-->R shunt from PDA or vasoconstriction following perinatal depression)
- RF: PDA, sepsis, LV failure
- TX: Increase PEEP, assess clotting factors and admin blood products, Tx PDA, Consider echo
75
CF
- thick mucous and airway obstruction, excessive neutrophil inflammatory response
- Postnatal testing: ↑IRT ( can be ↑ due to GI abnormality); Repeat IRT or CFTR panels, gold standard is sweat Cl test (>60);↓ fecal elastase - 1 = early pancreatic insufficiency marker
- Clinical: 1. Pancreatic insufficiency 2. Chronic obstructive Airway Dz (Pseudomonas, S Aureus) 3. bilateral agenesis of vas deferens 4. Other: Meconium Ileus, nasal polyposis, mucocele, sinusitis, GI CA, Liver Dz,
- Tx: Airway clearance, Pancreatic enzymes, lipid soluble vitamins, anti inflamm agents, Infection control, CFTR modulators
76
Inspiratory Stridor
1. Supraglottic obstruction: Nose, nasopharynx, oropharynx, hypopharynx - narrows during insp.
2. Less with crying but worse in supine position because gravity moves tongue posterior
3. DD: Pierre Robin & Treacher Collins; Macroglossia (BW, hypothyroidism, glycogen storage dz, T 21); Choanal atresia; thyroglossal duct cyst
77
Biphasic Stridor
1. Laryngeal obstruction (vocal cords, subglottis, extrathoracic trachea) - fixed size during insp and exp
2. Worse with agitation, Most common stridor as this is narrowest part of airway
3. DD: Laryngomalacia, Vocal cord paralysis, Congenital subglottic stenosis, laryngeal web, cyst
78
Expiratory Stridor
1. Intrathoracic trachea and bronchi - narrows during exp
2. Less common than laryngeal stridor but often more serious
3. DD: tracheomalacia, tracheal stenosis, external compression
79
Vascular Rings
- Complete circle around trachea and esophagus presenting with feeding and respiratory
1. Double aortic arch (40%): prevailing R and L 4th branchial arches
2. R Aortic arch with ligamentum arteriosum/PDA (30%): persistence of R 4th branchial arch
- Incomplete circle
1. Aberrant R Subclavian (20%): SA arises from descending Ao; mild feeding symptoms, most often SA is post to esophagus
2. Anomalous origin of innominate artery (10%); often with stridor or cough
3. Aberrant L PA - "PA sling"; resp and feeding difficulties
Barium Swallow is diagnostic
Echo and/or angio to confirm
80
CDH
- most are nonsyndromic (Fryns syndrome, Denys Drash, CDL, Marfan, spondylocostal dysostosis, craniofrontonasal syndrome)
- L (85%) > R > bilateral (1%)
- associated anomalies in 40%:CHD, undescended testes, Meckel diverticulum, unilateral kidney
- Most often occurs at foramen of bochdalek (70-90%), less commonly at ant midline through Mogagni hernia (10-30%, most on R side)
- polyhydramnios, absent gastric bubble, SCAPHOID Abdomen, L sided (intestines, spleen, stomach and/or liver in chest) R sided (almost all have liver)
- R sided associated with GBS PNA
- Hernia sac (21-47%) most often contains intestine and spleen and severe if liver and stomach
- assoc pulm HTN
81
CDH Outcomes
1. Herniated Contents:
- L Sided CDH ( Intestines only - typically good lung development; Above & Stomach &/or spleen: Intermediate risk; Above and liver: high risk for M&M and need for ECMO
- R sided CDH: worse outcome if >50% liver in chest
2. Sac = BETTER
3. Prenatal Lung Size (LHR)
<1.0: poor
>1.4: good
Liver involvement and LHR <0.8; high mortality
4. Postnatal Course
82
Diaphragmatic Paralysis
R>L, 9:1 unilat:bilat
Assoc with phrenic n injury with birth or CT surg
Bilat also assoc with NM disorders
Unilat: unequal chest movement, belly dancer sign
Bilat: Immediate RF, paradoxical movement of abdomen during insp
Diagnosis: Fluoroscopy or US; CXR if unilat
Tx: CPAP & surgical plication
83
Transudate v Exudate
1. pH: > 7.4 v < 7.4
2. WBC < 1000 v >1000
3. Protein <3 g/dL. v >3
4. Glucose = serum v < Serum
5. SG <1.016 v > 1.016
6. LDH < 200 v. >200
7. Pleural:Serum LDH <0.6. v. >0.6
8. Etiology CHF, nephrotic, NIHF, Iatrogenic v Inflamm & Infection
9. Path. Hydrostatic & Oncotic Forces v Leaky capillaries
84
Chylothorax
1. Common in fetus with chromosomal or major malformations
2. Thoracic duct obstruction --> may lead to pulm hypoplasia
3. R lung> L Lung > bilat
4. Similar to exudative hydrothorax, xanthochromic, Lymphocytic predom (>70%), high protein, high TG
5. fetal thoracocentesis? octreotide? thoracic duct ligation?
6. Milky fluid if being fed
7. TPN or formula with MCT to bypass Lymph system
85
Congenital Lobar Emphysema
1. LUL (45%) >RML (30%) >RUL (20%)
2. M>F
3. ↑ risk of CHD
4. Disruption of bronchopulmonary development leading to ball valve effect with air trapping
5. May need lobectomy
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