PULMONARY DISEASE IN PREGNANCY. Aileen Mickey, MD, FCCP Medical Director, EvergreenHealth Pulmonary Service Line

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1 PULMONARY DISEASE IN PREGNANCY Aileen Mickey, MD, FCCP Medical Director, EvergreenHealth Pulmonary Service Line

2 TOPICS Physiologic Changes During Pregnancy Asthma GERD Smoking Sleep Apnea Infection VTE Pulmonary Hypertension Acute Events

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4 PHYSIOLOGIC CHANGES Upper Airway Thoracic Cage Lung Volumes / Function Ventilation Cardiac

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6 UPPER AIRWAY Estrogen increases mucosal congestion and histamine reactivity 30% develop rhinitis starting in the first trimester Voice change Nasal polyps can worsen and recur Nasal granuloma gravidum Upper airway edema and mucus hypersecretion Snoring, sleep apnea

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8 INTERVENTIONS Nasal saline and / or nasal steroids for rhinitis Second generation antihistamines are Class B, except for Allegra (fexofenadine) which is class C Elevate head of bed Sleep apnea awareness

9 THORACIC CAGE Relaxation of the ligamentous attachments of the ribs Increased circumference of the lower chest wall Elevation of the diaphragm 4-5 cm, but normal excursion Normal muscle strength

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11 LUNG VOLUMES / FUNCTION Lung volumes decrease due to elevation of the diaphragm Partially compensated for by increased chest wall diameter Functional residual capacity decreases by 10 20% Decreased oxygen reserve Airway function is normal (spirometry will be normal)

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13 VENTILATION Increased central respiratory drive by week 13 Progesterone stimulates respiratory center and increases sensitivity to CO2 TV increases by 30% resulting in increased minute ventilation RR increases in the 3 rd trimester Increased minute ventilation is the most important mechanism for physiologic dyspnea of pregnancy Anemia and nasal congestion contribute

14 ABG FINDINGS CO2 production increases aby 1/3 to ½ by third trimester Minute ventilation increase more than CO2 production resulting in respiratory alkalosis ph (normal ) pco (normal 40) pao2 remains normal

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16 DISTINGUISHING NORMAL SOB FROM DISEASE Respiratory rate > 20 pco2 < 28 or > 35 Hypoxia Abrupt onset of symptoms Abnormal spirometry, CXR, echo or other testing

17 CARDIAC Increase in maternal blood volume by 2L (40%) Increase RBC mass by 20 30% causing relative anemia Increase venous capacitance to accommodate increased volume Increased LV compliance and decreased SVR 30 40% increase in CO by 26 weeks Increased heart rate by 5 weeks 10 20% decrease in DBP by 28 weeks

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19 ASTHMA Rule of thirds Metanalysis (2006) showed 20% pregnant women with asthma required treatment for flare during pregnancy, 6% of those required hospital admission Most common triggers are medication noncompliance, viral URI & GERD Most exacerbation occur in the 2 nd trimester 10% have exacerbations during delivery Overall no increased risk of preterm delivery or preeclampsia with exacerbations, but severe exacerbations increases risk of LBW

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23 INHALED CORTICOSTEROIDS INHALER STRENGTH LOW MEDIUM HIGH Qvar beclomethasone Pulmicort Flex budesonide Flovent HFA fluticasone Flovent Disk fluticasone Asmanex Twist mometasone Alvesco ciclesonide 40, 80 mcg mcg BID mcg BID > 240 mcg BID 90, 180 mcg 90 mcg BID 180 mcg BID 360 mcg BID 110, 220 mcg 110 mcg BID 220 mcg BID 440 mcg BID 100, 250, 500 mcg 100 mcg BID 250 mcg BID 500 mcg BID 110, 220 mcg 110 mcg qd 220 mcg qd 440 mcg qd 80, 160 mcg 80 mcg BID 160 mcg BID 320 mcg BID

24 LONG ACTING BETA AGONISTS (LABA) INHALER Serevent Disk (salmeterol) Foradil (formoterol) Arcapta (indacaterol) DOSE 1 puff BID 1 puff BID 1 puff qd

25 ICS / LABA COMBINATIONS INHALER MEDIUM DOSE HIGH DOSE Advair HFA (115/21, 230/21 mcg) Fluticasone/salmeterol Advair Disk (250/50, 500/50 mcg Fluticasone/salmeterol Symbicort (80/4.5, 160/4.5 mcg) Budesonide/formoterol Dulera (100/5, 200/5 mcg) Mometasone/formoterol) Breo Ellipta (100/25, 200/25 mcg) Fluticasone/vilanterol 2 puffs BID (115/21 mcg) 1 puff BID (250/50 mcg) 2 puffs BID (80/4.5 mcg) 2 puffs BID (100/5 mcg) 1 puff qd (100/25 mcg) 2 puffs BID (230/21 mcg) 1 puff BID (500/50 mcg) 2 puffs BID (160/4.5 mcg) 2 puffs BID (200/5 mcg) 1 puff qd (200/25 mcg)

26 RISK OF ASTHMA MEDICATIONS SABAs (albuterol) are safe LABAs have limited data but deemed safe LAMAs have no data, avoid ICS reduce asthma exacerbations, improve lung function and have NO association with congenital malformations Oral steroids deemed safe LTRAs (singulair) have no data Theophylline generally not used secondary to side effects

27 ASTHMA MANAGEMENT TAKE HOME Inhaled steroids reduce the risk of adverse outcomes in pregnant asthmatics Most important point is to continue treatment for asthma: benefits of inhalers far outweigh any risks Aggressive treatment of exacerbations Control GERD Smoking cessation

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29 GERD 30-50% of pregnant women complain of reflux symptoms Common cause of cough Common trigger for asthma exacerbations Source of aspiration pneumonia Risk factors include weight gain, older age, h/o GERD

30 GERD TREATMENT Dietary changes Elevate head of bed Antacids H2 blockers Proton pump inhibitors

31 SAFETY OF PPI All are category B except omeprazole which is category C Data for categorization is old Large study in Denmark 840,000 births No association between use of PPI in 1 st trimester and birth defects Omeprazole was the most commone PPI used

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33 SMOKING Worsens underlying asthma Associated clearly with LBW in proportion to amount smoked May be associated with cognitive and neurobehavioral defects Nicotine easily crosses the placental barrier causing direct fetal exposure Infant exposure may increase risk of SIDS Infant exposure increases risk of viral infections and rate of childhood asthma

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35 SLEEP APNEA Not well studied in pregnant patients Prevalence in women of childbearing age is 5%, unclear prevalence in pregnancy Traditional screening questionnarres don t apply Snoring alone is not associated with increased fetal risk Hypoxia is the concern Presence may increase risk of gestational DM Presence may be associated with pregnancy induced HTN and preeclampsia

36 OSA EVALUATION Patients with preexisting OSA should have their CPAP adjusted to auto settings Patients with symptoms, preexisting obesity, hypertension should be screened Overnight oximetry is simple and helpful to exclude hypoxia Home sleep test Treatment guidelines are the same as for nonpregnant patients with the emphasis on use of auto pressure settings.

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38 IMMUNITY IN PREGNANCY Maternal immunity is modulated rather than simply suppressed Respond to pathogens based on the pathogen and stage of pregnancy Fetal-placental system has it s own immune response Modulation results in increased susceptibility to viral infections in particular Mother is also more sensitive to proinflammatory stimuli

39 PNEUMONIA Prevalence is not increased, but complications are increased in pregnant patients Most frequent non-obstetrical infection Third leading cause of indirect obstetrical death Increased risk of preterm labor if occurs in 3 rd trimester In hospitalized pregnant women with pneumonia there is increased risk of LBW, preterm labor, low apgars, C-section, preeclampsia and eclampsia

40 BACTERIAL PNEUMONIA Strep pneumococcus most common, followed by mycoplasma, H. Flu and legionella Penicillin, cephalosporins and macrolides deemed safe to use Clindamycin probably safe for penicillin allergic patients

41 INFLUENZA PNEUMONIA Increased risk of pneumonia in pregnant patients who contract influenza Tamiflu and Relenza are category C, however given increased risk of complications including hypoxia and ARDS, CDC recommends treatment for influenza with either drug in the first 48 hours of symptoms Flu vaccine can and should be administered at in any trimester

42 VARICELLA PNEUMONIA Pneumonia occurs in 16% of primary varicella infections More common in the 2 nd and 3 rd trimesters In maternal primary infection, 24% of fetuses will become infected In 1 st trimester about 2% will develop fetal congenital varicella syndrome Post partum maternal infection results in infant infection in 17 30% of cases Increases risk of preterm birth VZIG should be given within 96 hours of maternal exposure for prevention Treated with acyclovir if rash appears

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44 VENOUS THROMBOEMBOLISM Leading cause of morbidity and mortality in pregnancy and peripartum period 5 times more common in pregnant vs. nonpregnant age matched controls Highest risk is in the post partum period Increased risk due to venous stasis and increased clotting factors (II, VII, X) Maternal risk factors include older age, C-section, bed rest, hemorrhage, multiparity, preexisting obesity and sepsis Preexisting APC resistance increases risk fold in heterozygotes and 100 fold in homozygotes

45 DIAGNOSIS ATS STATEMENT

46 DIAGNOSIS - SOGC

47 ACR APPROPRIATENESS CRITERIA

48 RADIATION AND DYE RISK Fetal exposure >= 0.01 Gy increases cancer risk in 1 st two decades of life from % Fetal exposure >= 0.1 Gy considered threshold for tetratogenecity CTPA fetal dose mgy, indirect exposure Contrast dye does not have teratogenic effects CTPA maternal breast dose 10 mgy (mammogram is 3mGy) VQ fetal dose mgy Fetus directly exposed to radiotracer in VQ

49 REAL WORLD DIAGNOSIS D-dimer not useful Ultrasound legs as first step, if positive then treat If ultrasound negative, proceed to CTPA

50 TREATMENT OF DVT/PE LMWH acutely DC LMWH 24 hours prior to delivery (switch to unfractionated heparin) Minimum total treatment 3 months Continue LMWH or warfarin at least 6 weeks post partum

51 PULMONARY HYPERTENSION Patients with preexisting PAH should avoid pregnancy When PAH present, PVR can not decrease to accommodate increased blood volume and cardiac output resulting in RV failure Pre-prostacyclin era, mortality was 30 56% If no h/o PAH but suspect, get echo and exclude PE Patients should be referred ASAP to a tertiary care center for PAH for management

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53 ACUTE ISSUES Peripartum cardiomyopathy Tocolytic pulmonary edema Aminiotic fluid embolism ARDS

54 PERIPARTUM CARDIOMYOPATHY Usually occurs during the final month of pregnancy through 5 months post partum Occurs in < 0.1% of pregnancies, but morbidity and mortality is up to 32% Diagnosis by echo and exclusion of other causes Outcome variable Treatment similar to nonischemic CM Unclear eitiology

55 TOCOLYTIC PULMONARY EDEMA Occurs during use of Beta agonists for labor induction Prevalence 0.3 9% cases when these are used Prolonged catecholamines can cause myocardial dysfunction and increased capillary permeability Worsened by administration of IVF and glucocorticoids Treatment is drug cessation, diursesis and correction of hypoxia

56 AMNIOTIC FLUID EMBOLISM Rare (1 case per 80,000 births) Mortality between 10 80% (poor data) Usually occurs during L&D but can occur with any uterine manipulation Amniotic fluid enters maternal circulation via endocervical veins or uterine tears Causes obstruction of pulmonary vessels, pulmonary hypertension and RV failure Supportive care

57 ARDS Aspiration pneumonia Post partum pyelonephritis with sepsis Preeclampsia Amniotic fluid embolism Tocolytic pulmonary edema Chorioamnionitis Bacterial or viral pneumonia

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