Pocket ObGyn – Influenza / Asthma in Pregnancy
See Abbreviations
Vaccination and Prevention
- Pregnant women are at risk for sev infxn & death than the general pop (Obstet Gynecol
2010;116:1006)
- ACOG & the CDC’s Advisory Committee on Immunization Practices recommend that all pregnant women be vaccinated against influenza, regardless of trimester (MMWR 2010;59(rr08)) mat/fetal safety of influenza vaccination in Preg is well established (Am J Obstet Gynecol 2012;207(3 Suppl)). Antepartum vaccination ® decreased stillbirth, neonat death & premature deliv, w/ no in congen anomalies (Obstet Gynecol 2012;120:532).
- Mat vaccination provides passive immunity to the neonate through 6 mo of age (N Engl J Med 2008;359(15):1555). Pregnant women should receive the trivalent inactivated (killed) injection vaccine only, & not the LAIV;
- Pregnant/postpartum women do not need to avoid contact w/ those who have received Postpartum/breastfeeding women can receive LAIV.
- Data do not support adverse effects attributable to preservative thimerosal (MMWR 2010;59(rr08)). Preservative eliminated or reduced in most Proven protection against serious dz outweighs theoretical concerns regarding preservative.
Prophylaxis and Treatment (MMWR 2011;60(1):1)
- Clinical dx is preferred (abrupt onset fever, cough, myalgia) to lab dx for rapid rx
- Oseltamivir & zanamivir are both Preg Category Zanamivir may be preferable in Preg b/c of limited systemic Absorp, but avoid in pts w/ comorbid respiratory dz. Most effective if £48 h of sx (Obstet Gynecol 2010;115(4):717).
- For ppx after exposure during Preg or up to 2 w postpartum: Zanamivir 10 mg (2 puffs inhaled) daily
Oseltamivir 75 mg PO daily
Duration: 10 d (household exposure), 14 d (hospital exposure), 7 d (other)
- For rx w/ onset of sx
Zanamivir 10 mg (2 puffs inhaled) daily ´ 5 d Oseltamivir 75 mg PO twice daily ´ 5 d
Can consider longer rx for severely ill pts
Additional Considerations
- Women w/ influenza hospitalized on labor & deliv wards should have respiratory precautions per hospital std for influenza
- Discuss the need for neonat antivirals or mat–neonat separation w/ pediatricians
- Postpartum, women w/ influenza should express breast milk, rather than Milk may still go to the infant, as oseltamivir is poorly excreted (Int J Infect Dis 2008;12:451).
Asthma and Pregnancy
(Obstet Gynecol 2008;111:457; NIH pub no. 08-4051)
Definitions/Pathophysiology
- Chronic airway inflammation w/ hyperresponsiveness to various stimuli & partially reversible airway obst
- Sev cases a/w increased prematurity, cesarean deliv, preeclampsia, growth restriction, & mat morbidity/mortality
- Mat–fetal pathology caused by mat Decreased FEV1 ® low birth weight/ prematurity.
Diagnosis
- Wheeze, cough, SOB, chest tightness; fluctuating; often worse at night; worse w/ known triggers (allergens, exercise, infections). Consider GERD, postnasal drip w/ cough, bronchitis in diff
- Airway obst on spirometry, reversible w/ bronchodilator therapy
- Document h/o hospitalization, ICU stay, intubation, & steroid Preg may improve,
worsen or have no effect on asthma severity (rule of 1⁄³’s). Past pregnancies may better predict course of subseq pregnancies.
Asthma severity classification | ||||
Severity |
Symptom
freq |
Nighttime
awakening |
Interference
w/ activity |
FEV1 or peak
flow (% of best) |
Mild
intermittent |
<2 d/w | <2´/mo | None | >80 |
Mild persistent | 2–6 d/w | >2´/mo | Minor | >80 |
Mod persistent | Daily | >1´/w | Some | 60–80 |
Sev persistent | All day | >4´/w | Extreme | <60 |
From Dombrowski MP, Schatz M, ACOG Committee on Practice Bulletins-Obstetrics. ACOG practice bulletin: Clinical management guidelines for obstetrician-gynecologists number 90, February 2008: Asthma in pregnancy. Obstet Gynecol. 2008;111(2 Pt 1):457–464. doi:10.1097/AOG.0b013e3181665ff4. |
Treatment
Asthma management, outpatient therapies | |
Severity | Mgmt |
Mild intermittent | Short-acting b-agonist (albuterol) as needed |
Mild persistent | ADD: Low-dose inhaled Cort. Alternative: Cromolyn, leukotriene receptor antag (montelukast), or theophylline. |
Mod persistent | ADD: Long-acting b-agonist (salmeterol), OR change to mediumdose inhaled Cort ± salmeterol. Alternative: Low-dose or medium-dose inhaled Cort + leukotriene receptor antag or theophylline. |
Sev persistent | CHANGE to high-dose inhaled Cort + salmeterol ± oral Cort (prednisone). Alternative: High-dose inhaled Cort w/ theophylline ± oral Cort. |
From Dombrowski MP, Schatz M, ACOG Committee on Practice Bulletins-Obstetrics. ACOG practice bulletin: Clinical management guidelines for obstetrician-gynecologists number 90, February 2008: Asthma in pregnancy. Obstet Gynecol. 2008;111 (2 Pt 1):457–464. doi:10.1097/AOG.0b013e3181665ff4. |
- Rx for acute asthma exacerbation
Supplemental O2 to maintain sat >95% (important for fetal oxygenation) Albuterol nebulizer q20min ´ 3, then q4h
Consider inhaled ipratropium on presentation (0.5 mg neb/8 puffs MDI) Systemic corticosteroids; prednisone 40–80 mg PO ´ 5–10 d (until PEFR >70%)
• Triage for acute presentation of asthma in Preg
FEV1 or PEFR >70% after rx, no distress, reassuring fetal status ® discharge FEV1 or PEFR 50–70% after rx ® individualize disposition
FEV1 or PEFR <50% after rx ® hospitalize
If poor resp/sev sx, drowsiness, confusion, pCO2 >40 mmHg consider ICU admission ± intubation
Arrange follow-up w/i 5 d postdischarge
Surveillance During Pregnancy
- Assess asthma status w/ PEFR at each prenatal visit; adjust maint regimen
- Prepare Asthma Action Plan & instruct on Eg, www.nhlbi.nih.gov/health/public/ lung/asthma/asthma_actplan.pdf.
- Focus on avoidance of allergens/irritants (eg, tobacco smoke, GERD, mold, dust mites, dander, cockroaches)
- Albuterol & budesonide are preferred short-acting b-agonist/inhaled steroid in Preg. Consider weekly fetal testing (NST, AFI, or BPP) from 32–34 w if mod–sev asthma or poor
Intrapartum Considerations
- Maintain hydration, continue asthma meds, including systemic steroids
- Consider cesarean deliv if unstable asthma & mature fetus
- Avoid carboprost tromethamine (Hemabate)
- ASA, indocin, other NSAIDs can cause asthmatic bronchospasm
- No contraindication to breastfeeding postpartum for asthma meds above