Asthma in pregnancy: Difference between revisions

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==Pathophysiology==
==Pathophysiology==
During pregnancy, due to high levels of progesterone, minute ventilatory rate is increased causing compensated [[respiratory alkalosis]].<ref name="pmid16443140">{{cite journal| author=Wise RA, Polito AJ, Krishnan V| title=Respiratory physiologic changes in pregnancy. | journal=Immunol Allergy Clin North Am | year= 2006 | volume= 26 | issue= 1 | pages= 1-12 | pmid=16443140 | doi=10.1016/j.iac.2005.10.004 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=16443140  }} </ref> Hence the [[arterial blood gases]] may reveal a higher PO<sub>2</sub> and lower PCO<sub>2</sub> with mild alkalotic PH. Normal PCO<sub>2</sub> during pregnancy is suggestive of impending [[respiratory failure]].
* During pregnancy, due to high levels of progesterone, minute ventilatory rate is increased causing compensated [[respiratory alkalosis]].<ref name="pmid16443140">{{cite journal| author=Wise RA, Polito AJ, Krishnan V| title=Respiratory physiologic changes in pregnancy. | journal=Immunol Allergy Clin North Am | year= 2006 | volume= 26 | issue= 1 | pages= 1-12 | pmid=16443140 | doi=10.1016/j.iac.2005.10.004 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=16443140  }} </ref>
 
* The [[arterial blood gases]] may reveal a higher PO<sub>2</sub> and lower PCO<sub>2</sub> with mild alkalotic PH. Normal PCO<sub>2</sub> during pregnancy is suggestive of impending [[respiratory failure]].
Asthma is characterized by broncho-constriction or inflammation of airways with production of thick mucoid secretions. In a small prospective study involving 16 asthmatic pregnant women, hyper-reactivity was seen to be lower as evidenced by a reduction in minimum medication requirements.<ref name="pmid2679270">{{cite journal| author=Juniper EF, Daniel EE, Roberts RS, Kline PA, Hargreave FE, Newhouse MT| title=Improvement in airway responsiveness and asthma severity during pregnancy. A prospective study. | journal=Am Rev Respir Dis | year= 1989 | volume= 140 | issue= 4 | pages= 924-31 | pmid=2679270 | doi= | pmc= | url= }} </ref>
* Asthma is characterized by broncho-constriction or inflammation of airways with production of thick mucoid secretions. In a small prospective study involving 16 asthmatic pregnant women, hyper-reactivity was seen to be lower as evidenced by a reduction in minimum medication requirements.<ref name="pmid2679270">{{cite journal| author=Juniper EF, Daniel EE, Roberts RS, Kline PA, Hargreave FE, Newhouse MT| title=Improvement in airway responsiveness and asthma severity during pregnancy. A prospective study. | journal=Am Rev Respir Dis | year= 1989 | volume= 140 | issue= 4 | pages= 924-31 | pmid=2679270 | doi= | pmc= | url= }} </ref>


==Natural History, Complications and Prognosis==
==Natural History, Complications and Prognosis==
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==Diagnosis==
==Diagnosis==
===History and Symptoms===
===History and Symptoms===
Majority of patients have personal or family history of other [[atopic diseases]]. The clinical presentation of asthma in pregnancy varies with individuals both spontaneously and with therapy. In some, asthma is characterized by '''chronic respiratory impairment''' and others experience '''episodic attacks''' secondary to a number of triggering events including [[upper respiratory tract infection]], [[stress]], cold air, [[Exercise induced asthma|exercise]], exposure to [[allergen]]  (such as pets, dust, mites, pollen) or air pollutants (such as smoke or traffic fumes).  
* The majority of patients have personal or family history of other [[atopic diseases]].
The '''cardinal symptoms''' of asthma include:
* The clinical presentation of asthma in pregnancy varies with individuals both spontaneously and with therapy.
*[[wheeze|Loud expiratory wheeze]]
* In some cases, asthma is characterized by '''chronic respiratory impairment''' and others experience '''episodic attacks''' secondary to a number of triggering events including [[upper respiratory tract infection]], [[stress]], cold air, [[Exercise induced asthma|exercise]], exposure to [[allergen]]  (such as pets, dust, mites, pollen) or air pollutants (such as smoke or traffic fumes).  
*[[cough|Nocturnal cough]]
* The '''cardinal symptoms''' of asthma include:
*[[Dyspnea]]
:*[[wheeze|Loud expiratory wheeze]]
*[[Chest tightness]]
:*[[cough|Nocturnal cough]]
*[[Stridor]] in the absence of a [[wheeze]] may be confused with a [[COPD|COPD-type]] of disease and hence it is difficult to diagnose asthma based upon the history alone.<ref name="pmid6861547">Pratter MR, Hingston DM, Irwin RS (1983) [http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=6861547 Diagnosis of bronchial asthma by clinical evaluation. An unreliable method.] ''Chest'' 84 (1):42-7. PMID: [http://pubmed.gov/6861547 6861547]</ref><ref name="pmid2178528">Irwin RS, Curley FJ, French CL (1990) [http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=2178528 Chronic cough. The spectrum and frequency of causes, key components of the diagnostic evaluation, and outcome of specific therapy.] ''Am Rev Respir Dis'' 141 (3):640-7. PMID: [http://pubmed.gov/2178528 2178528]</ref><ref name="pmid2802893">Pratter MR, Curley FJ, Dubois J, Irwin RS (1989) [http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=2802893 Cause and evaluation of chronic dyspnea in a pulmonary disease clinic.] ''Arch Intern Med'' 149 (10):2277-82. PMID: [http://pubmed.gov/2802893 2802893]</ref>
:*[[Dyspnea]]
:*[[Chest tightness]]
:*[[Stridor]] in the absence of a [[wheeze]] may be confused with a [[COPD|COPD-type]] of disease and hence it is difficult to diagnose asthma based upon the history alone.<ref name="pmid6861547">Pratter MR, Hingston DM, Irwin RS (1983) [http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=6861547 Diagnosis of bronchial asthma by clinical evaluation. An unreliable method.] ''Chest'' 84 (1):42-7. PMID: [http://pubmed.gov/6861547 6861547]</ref><ref name="pmid2178528">Irwin RS, Curley FJ, French CL (1990) [http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=2178528 Chronic cough. The spectrum and frequency of causes, key components of the diagnostic evaluation, and outcome of specific therapy.] ''Am Rev Respir Dis'' 141 (3):640-7. PMID: [http://pubmed.gov/2178528 2178528]</ref><ref name="pmid2802893">Pratter MR, Curley FJ, Dubois J, Irwin RS (1989) [http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&retmode=ref&cmd=prlinks&id=2802893 Cause and evaluation of chronic dyspnea in a pulmonary disease clinic.] ''Arch Intern Med'' 149 (10):2277-82. PMID: [http://pubmed.gov/2802893 2802893]</ref>


===Physical Examination===
===Physical Examination===
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====Respiratory Examination====
====Respiratory Examination====
=====Inspection=====
=====Inspection=====
Retraction of accessory muscles of respiration such as [[sternocleidomastoid]], abdominal and [[pectoralis]] muscles with each breath
*Retraction of accessory muscles of respiration such as [[sternocleidomastoid]], abdominal and [[pectoralis]] muscles with each breath
=====Percussion=====
=====Percussion=====
Hyper-resonant in all lung feilds.
*Hyper-resonant in all lung fields.
=====Auscultation=====
=====Auscultation=====
*Long, high-pitched expiratory [[wheeze]]
*Long, high-pitched expiratory [[wheeze]]
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===Pulmonary Function Testing===
===Pulmonary Function Testing===
In normal pregnancy, [[FEV1]], [[vital capacity]], [[total lung capacity]], [[FEV1]]/[[FVC]] remains unchanged while [[functional residual capacity]], [[residual volume]] decreases with increase in [[tidal volume]]. [[FEV1]] may decrease when pregnant women lie in supine position. Hence pregnant women with acute asthma should rest in seated position rather than lying down<ref name="pmid2623214">{{cite journal| author=Nørregaard O, Schultz P, Ostergaard A, Dahl R| title=Lung function and postural changes during pregnancy. | journal=Respir Med | year= 1989 | volume= 83 | issue= 6 | pages= 467-70 | pmid=2623214 | doi= | pmc= | url= }} </ref>.
* In normal pregnancy, [[FEV1]], [[vital capacity]], [[total lung capacity]], [[FEV1]]/[[FVC]] remains unchanged while [[functional residual capacity]], [[residual volume]] decreases with increase in [[tidal volume]]. [[FEV1]] may decrease when pregnant women lie in supine position.
 
* Pregnant women with acute asthma should rest in seated position rather than lying down.<ref name="pmid2623214">{{cite journal| author=Nørregaard O, Schultz P, Ostergaard A, Dahl R| title=Lung function and postural changes during pregnancy. | journal=Respir Med | year= 1989 | volume= 83 | issue= 6 | pages= 467-70 | pmid=2623214 | doi= | pmc= | url= }} </ref>
As with non-pregnant asthmatics, pregnant asthmatics have reduced [[FEV1]] and increased [[residual volume]], [[functional residual capacity]], and [[total lung capacity]] which can be reversed with [[bronchodilator]]s.
* As with non-pregnant asthmatics, pregnant asthmatics have reduced [[FEV1]] and increased [[residual volume]], [[functional residual capacity]], and [[total lung capacity]] which can be reversed with [[bronchodilator|bronchodilators]].


===Methacholine Challenge Test===
===Methacholine Challenge Test===
Methacholine challenge test is usually not recommended in pregnancy as it can have teratogenic effects<ref>[http://www.fda.gov/ohrms/dockets/dailys/04/aug04/080904/04p-0359-cp00001-03-Attachment-02-vol1.pdf FDA]</ref> (Pregnancy Category C).
*Methacholine challenge test is usually not recommended in pregnancy as it can have teratogenic effects<ref>[http://www.fda.gov/ohrms/dockets/dailys/04/aug04/080904/04p-0359-cp00001-03-Attachment-02-vol1.pdf FDA]</ref> (Pregnancy Category C).


==Treatment<ref name="pmid17983880">{{cite journal| author=National Asthma Education and Prevention Program| title=Expert Panel Report 3 (EPR-3): Guidelines for the Diagnosis and Management of Asthma-Summary Report 2007. | journal=J Allergy Clin Immunol | year= 2007 | volume= 120 | issue= 5 Suppl | pages= S94-138 | pmid=17983880 | doi=10.1016/j.jaci.2007.09.043 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17983880  }} </ref>==
==Treatment<ref name="pmid17983880">{{cite journal| author=National Asthma Education and Prevention Program| title=Expert Panel Report 3 (EPR-3): Guidelines for the Diagnosis and Management of Asthma-Summary Report 2007. | journal=J Allergy Clin Immunol | year= 2007 | volume= 120 | issue= 5 Suppl | pages= S94-138 | pmid=17983880 | doi=10.1016/j.jaci.2007.09.043 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=17983880  }} </ref>==
Line 88: Line 90:
===Treatment of acute exacerbation of asthma in pregnancy===
===Treatment of acute exacerbation of asthma in pregnancy===
*Oral or intravenous [[glucocorticoids]] is recommended for acute exacerbation of asthma similar to non-pregnant asthmatics<ref> Schatz, M, Wise, RA. Acute asthma in pregnancy. In: Acute Asthma: Assessment and Management, Corbridge T, et al (Eds), McGraw-Hill, New York 2000.</ref>.
*Oral or intravenous [[glucocorticoids]] is recommended for acute exacerbation of asthma similar to non-pregnant asthmatics<ref> Schatz, M, Wise, RA. Acute asthma in pregnancy. In: Acute Asthma: Assessment and Management, Corbridge T, et al (Eds), McGraw-Hill, New York 2000.</ref>.
*Use of [[methylxanthine]]s is not recommended in emergency setting as they do not provide additional benefit when compared to beta adrenergics and IV glucocorticoids<ref name="pmid8694041">{{cite journal| author=Wendel PJ, Ramin SM, Barnett-Hamm C, Rowe TF, Cunningham FG| title=Asthma treatment in pregnancy: a randomized controlled study. | journal=Am J Obstet Gynecol | year= 1996 | volume= 175 | issue= 1 | pages= 150-4 | pmid=8694041 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8694041  }} </ref>.
*Use of [[methylxanthine|methylxanthines]] is not recommended in emergency setting as they do not provide additional benefit when compared to beta adrenergics and IV glucocorticoids.<ref name="pmid8694041">{{cite journal| author=Wendel PJ, Ramin SM, Barnett-Hamm C, Rowe TF, Cunningham FG| title=Asthma treatment in pregnancy: a randomized controlled study. | journal=Am J Obstet Gynecol | year= 1996 | volume= 175 | issue= 1 | pages= 150-4 | pmid=8694041 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=8694041  }} </ref>
*[[Magnesium sulfate]] which is usually given during hypertensive conditions in pregnancy or [[preterm labor]] also have a beneficial effect on asthma by relaxing airway muscles<ref> Schatz, M, Wise, RA. Acute asthma in pregnancy. In: Acute Asthma: Assessment and Management, Corbridge T, et al (Eds), McGraw-Hill, New York 2000.</ref>.
*[[Magnesium sulfate]] which is usually given during hypertensive conditions in pregnancy or [[preterm labor]] also have a beneficial effect on asthma by relaxing airway muscles<ref> Schatz, M, Wise, RA. Acute asthma in pregnancy. In: Acute Asthma: Assessment and Management, Corbridge T, et al (Eds), McGraw-Hill, New York 2000.</ref>.
*Use of [[epinephrine]] should be avoided in pregnancy as it can lead to congenital malformations, fetal [[tachycardia]], and [[vasoconstriction]] of the uteroplacental circulation<ref name="pmid15637545">{{cite journal| author=National Heart, Lung, and Blood Institute. National Asthma Education and Prevention Program Asthma and Pregnancy Working Group| title=NAEPP expert panel report. Managing asthma during pregnancy: recommendations for pharmacologic treatment-2004 update. | journal=J Allergy Clin Immunol | year= 2005 | volume= 115 | issue= 1 | pages= 34-46 | pmid=15637545 | doi=10.1016/j.jaci.2004.10.023 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15637545  }} </ref>.
*Use of [[epinephrine]] should be avoided in pregnancy as it can lead to congenital malformations, fetal [[tachycardia]], and [[vasoconstriction]] of the uteroplacental circulation.<ref name="pmid15637545">{{cite journal| author=National Heart, Lung, and Blood Institute. National Asthma Education and Prevention Program Asthma and Pregnancy Working Group| title=NAEPP expert panel report. Managing asthma during pregnancy: recommendations for pharmacologic treatment-2004 update. | journal=J Allergy Clin Immunol | year= 2005 | volume= 115 | issue= 1 | pages= 34-46 | pmid=15637545 | doi=10.1016/j.jaci.2004.10.023 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15637545  }} </ref>


===Peripartum Management===
===Peripartum Management===
*Peripartum pain control can be managed with [[butorphanol]] or [[fentanyl]]. [[Morphine]] and [[meperidine]] should be avoided as they can induce release of [[histamine]] and possibly cause bronchoconstriction.
*Peripartum pain control can be managed with [[butorphanol]] or [[fentanyl]]. [[Morphine]] and [[meperidine]] should be avoided as they can induce release of [[histamine]] and possibly cause bronchoconstriction.
*[[Epidural anesthesia]] is preferred for pain control during labor in the gestational asthmatics. In case general anesthesia is required, [[ketamine]] and halogenated anesthetics are preferred as they have bronchodilatory effects.
*[[Epidural anesthesia]] is preferred for pain control during labor in the gestational asthmatics. In case general anesthesia is required, [[ketamine]] and halogenated anesthetics are preferred as they have bronchodilatory effects.
*Use of [[oxytocin]] is recommended in induction of [[labor]] and control of [[postpartum hemorrhage]]<ref name="pmid9580925">{{cite journal| author=Minerbi-Codish I, Fraser D, Avnun L, Glezerman M, Heimer D| title=Influence of asthma in pregnancy on labor and the newborn. | journal=Respiration | year= 1998 | volume= 65 | issue= 2 | pages= 130-5 | pmid=9580925 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=9580925  }} </ref>
*Use of [[oxytocin]] is recommended in induction of [[labor]] and control of [[postpartum hemorrhage]].<ref name="pmid9580925">{{cite journal| author=Minerbi-Codish I, Fraser D, Avnun L, Glezerman M, Heimer D| title=Influence of asthma in pregnancy on labor and the newborn. | journal=Respiration | year= 1998 | volume= 65 | issue= 2 | pages= 130-5 | pmid=9580925 | doi= | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=9580925  }} </ref>
*Use of [[prostaglandin]] E1 and E2 analogs are shown to be safe in pregnancy<ref name="pmid15284797">{{cite journal| author=Towers CV, Briggs GG, Rojas JA| title=The use of prostaglandin E2 in pregnant patients with asthma. | journal=Am J Obstet Gynecol | year= 2004 | volume= 190 | issue= 6 | pages= 1777-80; discussion 1780 | pmid=15284797 | doi=10.1016/j.ajog.2004.02.056 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15284797  }} </ref>. However, [[prostaglandin]] F2 alpha analogs should be avoided as they can induce [[bronchospasm]]<ref name="pmid8220872">{{cite journal| author=Arakawa H, Lötvall J, Kawikova I, Löfdahl CG, Skoogh BE| title=Leukotriene D4- and prostaglandin F2 alpha-induced airflow obstruction and airway plasma exudation in guinea-pig: role of thromboxane and its receptor. | journal=Br J Pharmacol | year= 1993 | volume= 110 | issue= 1 | pages= 127-32 | pmid=8220872 | doi= | pmc=PMC2176029 | url= }} </ref>. Ergot derivatives have similar property abd hence, should also be avoided.
*Use of [[prostaglandin]] E1 and E2 analogs are shown to be safe in pregnancy<ref name="pmid15284797">{{cite journal| author=Towers CV, Briggs GG, Rojas JA| title=The use of prostaglandin E2 in pregnant patients with asthma. | journal=Am J Obstet Gynecol | year= 2004 | volume= 190 | issue= 6 | pages= 1777-80; discussion 1780 | pmid=15284797 | doi=10.1016/j.ajog.2004.02.056 | pmc= | url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=15284797  }} </ref> However, [[prostaglandin]] F2 alpha analogs should be avoided as they can induce [[bronchospasm]].<ref name="pmid8220872">{{cite journal| author=Arakawa H, Lötvall J, Kawikova I, Löfdahl CG, Skoogh BE| title=Leukotriene D4- and prostaglandin F2 alpha-induced airflow obstruction and airway plasma exudation in guinea-pig: role of thromboxane and its receptor. | journal=Br J Pharmacol | year= 1993 | volume= 110 | issue= 1 | pages= 127-32 | pmid=8220872 | doi= | pmc=PMC2176029 | url= }} </ref> Ergot derivatives have similar property abd hence, should also be avoided.


==References==
==References==
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[[Category:Asthma]]
[[Category:Asthma]]
[[Category:Disease]]
[[Category:Disease]]
[[Category:Pulmonology]]  
[[Category:Pulmonology]]  

Revision as of 19:54, 3 October 2011

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-In-Chief: Varun Kumar, M.B.B.S. [2]; Lakshmi Gopalakrishnan, M.B.B.S. [3]

Overview

Asthma is one of the most common pulmonary conditions occurring during pregnancy[1] with a prevalence rate of 3.7% to 8.4% in United States during the period 1997-2001[2].

Pathophysiology

  • During pregnancy, due to high levels of progesterone, minute ventilatory rate is increased causing compensated respiratory alkalosis.[3]
  • The arterial blood gases may reveal a higher PO2 and lower PCO2 with mild alkalotic PH. Normal PCO2 during pregnancy is suggestive of impending respiratory failure.
  • Asthma is characterized by broncho-constriction or inflammation of airways with production of thick mucoid secretions. In a small prospective study involving 16 asthmatic pregnant women, hyper-reactivity was seen to be lower as evidenced by a reduction in minimum medication requirements.[4]

Natural History, Complications and Prognosis

Severe or poorly controlled asthma cause maternal hypoxia, hypercapnia and respiratory alkalosis which may impair fetal oxygenation and uteroplacental blood flow. Asthma during pregnancy may have negative impact on both mother and the child especially in severe or poorly controlled cases. Complications include:

Diagnosis

History and Symptoms

  • The majority of patients have personal or family history of other atopic diseases.
  • The clinical presentation of asthma in pregnancy varies with individuals both spontaneously and with therapy.
  • In some cases, asthma is characterized by chronic respiratory impairment and others experience episodic attacks secondary to a number of triggering events including upper respiratory tract infection, stress, cold air, exercise, exposure to allergen (such as pets, dust, mites, pollen) or air pollutants (such as smoke or traffic fumes).
  • The cardinal symptoms of asthma include:

Physical Examination

General appearance

Vitals

Respiratory Examination

Inspection
Percussion
  • Hyper-resonant in all lung fields.
Auscultation
  • Long, high-pitched expiratory wheeze
  • Ronchi
  • Bronchovesicular breath sounds
  • Silent chest among patients in distress is a sign of severe and complicated asthma

Cardiology Examination

Extremities

Clubbing

Lab Tests

Compensated respiratory alkalosis is the physiologic change noted in pregnancy secondary to hyperventilation due to high levels of progesterone. Asthma causes overlapping of respiratory acidosis over physiologic respiratory alkalosis and hence a modest elevation in PCO2 may be noted.

Pulmonary Function Testing

Methacholine Challenge Test

  • Methacholine challenge test is usually not recommended in pregnancy as it can have teratogenic effects[14] (Pregnancy Category C).

Treatment[15]

  • Monitor asthma control during all prenatal visits.
  • Asthmatic symptoms worsen in about a third during pregnancy and improve in a third; hence, medications should be adjusted accordingly.
  • Patients should rest in seated position rather than lying down[13]
  • Oxygen supplementation should be provided to maintain PO2 over 70mm Hg[16]
  • Regular monitoring and maintenance of lung function to ensure adequate oxygen supply to the fetus.
  • It is safer to treat asthma with medications than to have poorly-controlled asthma.

Treatment of chronic asthma in pregnancy

Treatment of acute exacerbation of asthma in pregnancy

  • Oral or intravenous glucocorticoids is recommended for acute exacerbation of asthma similar to non-pregnant asthmatics[17].
  • Use of methylxanthines is not recommended in emergency setting as they do not provide additional benefit when compared to beta adrenergics and IV glucocorticoids.[18]
  • Magnesium sulfate which is usually given during hypertensive conditions in pregnancy or preterm labor also have a beneficial effect on asthma by relaxing airway muscles[19].
  • Use of epinephrine should be avoided in pregnancy as it can lead to congenital malformations, fetal tachycardia, and vasoconstriction of the uteroplacental circulation.[20]

Peripartum Management

References

  1. ↑ Rey E, Boulet LP (2007). "Asthma in pregnancy". BMJ. 334 (7593): 582–5. doi:10.1136/bmj.39112.717674.BE. PMC 1828355. PMID 17363831.
  2. ↑ Kwon HL, Belanger K, Bracken MB (2003). "Asthma prevalence among pregnant and childbearing-aged women in the United States: estimates from national health surveys". Ann Epidemiol. 13 (5): 317–24. PMID 12821270.
  3. ↑ Wise RA, Polito AJ, Krishnan V (2006). "Respiratory physiologic changes in pregnancy". Immunol Allergy Clin North Am. 26 (1): 1–12. doi:10.1016/j.iac.2005.10.004. PMID 16443140.
  4. ↑ Juniper EF, Daniel EE, Roberts RS, Kline PA, Hargreave FE, Newhouse MT (1989). "Improvement in airway responsiveness and asthma severity during pregnancy. A prospective study". Am Rev Respir Dis. 140 (4): 924–31. PMID 2679270.
  5. ↑ 5.0 5.1 5.2 5.3 5.4 Liu S, Wen SW, Demissie K, Marcoux S, Kramer MS (2001). "Maternal asthma and pregnancy outcomes: a retrospective cohort study". Am J Obstet Gynecol. 184 (2): 90–6. doi:10.1067/mob.2001.108073. PMID 11174486.
  6. ↑ Perlow JH, Montgomery D, Morgan MA, Towers CV, Porto M (1992). "Severity of asthma and perinatal outcome". Am J Obstet Gynecol. 167 (4 Pt 1): 963–7. PMID 1415433.
  7. ↑ Lehrer S, Stone J, Lapinski R, Lockwood CJ, Schachter BS, Berkowitz R; et al. (1993). "Association between pregnancy-induced hypertension and asthma during pregnancy". Am J Obstet Gynecol. 168 (5): 1463–6. PMID 8498428.
  8. ↑ 8.0 8.1 Breton MC, Beauchesne MF, Lemière C, Rey E, Forget A, Blais L (2009). "Risk of perinatal mortality associated with asthma during pregnancy". Thorax. 64 (2): 101–6. doi:10.1136/thx.2008.102970. PMID 19008298.
  9. ↑ Triche EW, Saftlas AF, Belanger K, Leaderer BP, Bracken MB (2004). "Association of asthma diagnosis, severity, symptoms, and treatment with risk of preeclampsia". Obstet Gynecol. 104 (3): 585–93. doi:10.1097/01.AOG.0000136481.05983.91. PMID 15339773.
  10. ↑ Pratter MR, Hingston DM, Irwin RS (1983) Diagnosis of bronchial asthma by clinical evaluation. An unreliable method. Chest 84 (1):42-7. PMID: 6861547
  11. ↑ Irwin RS, Curley FJ, French CL (1990) Chronic cough. The spectrum and frequency of causes, key components of the diagnostic evaluation, and outcome of specific therapy. Am Rev Respir Dis 141 (3):640-7. PMID: 2178528
  12. ↑ Pratter MR, Curley FJ, Dubois J, Irwin RS (1989) Cause and evaluation of chronic dyspnea in a pulmonary disease clinic. Arch Intern Med 149 (10):2277-82. PMID: 2802893
  13. ↑ 13.0 13.1 Nørregaard O, Schultz P, Ostergaard A, Dahl R (1989). "Lung function and postural changes during pregnancy". Respir Med. 83 (6): 467–70. PMID 2623214.
  14. ↑ FDA
  15. ↑ National Asthma Education and Prevention Program (2007). "Expert Panel Report 3 (EPR-3): Guidelines for the Diagnosis and Management of Asthma-Summary Report 2007". J Allergy Clin Immunol. 120 (5 Suppl): S94–138. doi:10.1016/j.jaci.2007.09.043. PMID 17983880.
  16. ↑ http://www.nhlbi.nih.gov/health/prof/lung/asthma/astpreg.txt
  17. ↑ Schatz, M, Wise, RA. Acute asthma in pregnancy. In: Acute Asthma: Assessment and Management, Corbridge T, et al (Eds), McGraw-Hill, New York 2000.
  18. ↑ Wendel PJ, Ramin SM, Barnett-Hamm C, Rowe TF, Cunningham FG (1996). "Asthma treatment in pregnancy: a randomized controlled study". Am J Obstet Gynecol. 175 (1): 150–4. PMID 8694041.
  19. ↑ Schatz, M, Wise, RA. Acute asthma in pregnancy. In: Acute Asthma: Assessment and Management, Corbridge T, et al (Eds), McGraw-Hill, New York 2000.
  20. ↑ National Heart, Lung, and Blood Institute. National Asthma Education and Prevention Program Asthma and Pregnancy Working Group (2005). "NAEPP expert panel report. Managing asthma during pregnancy: recommendations for pharmacologic treatment-2004 update". J Allergy Clin Immunol. 115 (1): 34–46. doi:10.1016/j.jaci.2004.10.023. PMID 15637545.
  21. ↑ Minerbi-Codish I, Fraser D, Avnun L, Glezerman M, Heimer D (1998). "Influence of asthma in pregnancy on labor and the newborn". Respiration. 65 (2): 130–5. PMID 9580925.
  22. ↑ Towers CV, Briggs GG, Rojas JA (2004). "The use of prostaglandin E2 in pregnant patients with asthma". Am J Obstet Gynecol. 190 (6): 1777–80, discussion 1780. doi:10.1016/j.ajog.2004.02.056. PMID 15284797.
  23. ↑ Arakawa H, Lötvall J, Kawikova I, Löfdahl CG, Skoogh BE (1993). "Leukotriene D4- and prostaglandin F2 alpha-induced airflow obstruction and airway plasma exudation in guinea-pig: role of thromboxane and its receptor". Br J Pharmacol. 110 (1): 127–32. PMC 2176029. PMID 8220872.

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