Breathlessness in pregnancy ---respiratory resasons
1. Prof. M.C.Bansal
MBBS.,MS. FICOG. MICOG.
Founder Principal & Controller ,
Jhalawar Medical College And Hospital Jhalawar.
Ex Principal & controller MGMC and Hospital ,
Sitapura Jaipur.
2. Physiological causes of
Breathlessness in Pregnancy
Physiological breathlessness starts as early as 1st
or second trimester and increases in incidence as
gestation progress.
It occurs in 60 -70 % women and thus is the common
phenomenon , it is usually mild and seldom
incapacitate , the women to perform routine activity.
Breathlessness at rest is uncommon and tolerance to
light exercise and daily activity are usually not affected.
3. Physiological breathlessness----
Changes in lung function occur as result of
homeostasis owing to increasing demand of O 2 of
the growing fetus . , increased maternal BMR .
Minute ventilation is increased by 20-40 % ( tidal
volume x Respiratory rate ) Tidal volume is increased
but respiratory rate is not increased significantly.
4. Respiratory Causes.
Respiratory centre becomes more sensitive to CO2.
respiratory rate increases at rest even ,
Vertical diameter of thoracic cavity decreases due to up
pushing of diaphragm by enlarging uterus, Respiration
becomes more thoracic as abdominal movements with
respiration are restricted , In later period of pregnancy
there is flaring out of ribs there by anterio lateral diameter
of thoracic cage increase , vital capacity decrease more so
in lying down position , supine hypotension due to caval
compression by enlarged uterus also cause cardio
respiratory distress
.
5. Breathlessness due to Respiratory
Dysfunction
Dysfunctional breathing is common in young women hence while pregnant ,it
may continue.
Patient typically complains of breathlessness which is out of proportion to
clinical findings and able to perform daily activity . It may occur even at bed
rest . Pt describes it as “difficulty in taking full breath “ or “ felling a blockage in
the chesty “.
Pt may have psychological problem or psychiatric illness.
Vocal Cord Dysfunction---Presents as attacks of breathlessness similar to
asthma., with which it often co exist.10 % of acute asthma cases may infect be
due to vocal cord dysfunction. It can be diagnosed simply by clinical history
and spirometry., narrowed inspiratory flow volume loop
laryngoscopy will reveal adduction of voal cord on inspiration and some time
on expiration.
Frank strider / aspiratory wheeze on chest auscultation may be present., Which is
absent between attacks of breathlessness. .
6.
7. Breathlessness Causes, Reasons
and Solutions
www.normalbreathing.com/d/labored-breathlessness.php#.UPs2GSc73dk 3/5
The main causes of breathlessness and labored breathing (why it is hard
to breathe):
- constriction of airways due to hypocapnia in the airways
- reduced oxygen levels in the diaphragm and chest muscles due to
reduced oxygen transport
- tense states in the diaphragmatic and chest muscles due to arterial
hypocapnia.
Exacerbating reasons in the pathophysiology of labored breathing and
breathlessness are:
- mouth breathing (due to reduction in nitric oxide absorption and
alveolar CO2)
- chest breathing (due to reduction in arterial oxygenation)
- presence of inflammation and mucus in airways, causing further
narrowing or an obstruction of air flow (as in COPD).
Exertion, mouth breathing, physical exercise with mouth breathing, chest breathing, meals (eating
and
especially overeating), overheating, anxiety, stress, attempts to inhale deeply, deep breathing
exercises
with CO2 losses, poor posture, night sleep and many other factors are known causes of
hyperventilation. Hence, they worsen breathlessness and labored breathing.
9. Individual disorders--------
Upper Air Ways –
Nasal Obstruction-------
Due to rhinitis can occur in 30 % pregnant women .
As a result of mucosal edema , hyperaemia ,capillary
congestion and mucosal hyper secretion which is
caused by increased oestrogen level in pregnancy .
This occurs mostly in 3rd trimester and may lead to
breathlessness , particularly if severe.
10. Respiratory causes-------
Obstructive Air Ways Disease
Asthma is by far most obstructive air ways disease likely to encounter
in pregnancy. , occurring in 0.4 -7 % cases and patient are already
known to have it.
Patient develops intermittent breathlessness with wide spread
Expiratory wheeze , bronchial secretion and precipitated by exertion
and change in weather / temperature . Peak flow monitoring
willreve3al reduced peak flow with variability. Symptoms worse at late
night and early morning. Patient respond well to inhaled Beta –
agonist( broncho dilators )
Uncontrolled asthma----persistent troublesome symptoms , nocturnal
symptoms , frequent use of Beta –agonist inhalation with little relief ,
limitation of physical activity. They need hospitalization.
Asthma in pregnancy worsen in 1/2rd cases , remain unchanged in 1/3rd
and rest have improvement in their symptoms there by requiring less
dose of corticosteroids. NSAIDS use may trigger or worsen asthma.
11. Respiratory Causes-----
2. Cystic Fibrosis and Bronchiectasis
Usually pre existing and characterized by frequent
chest infection , increased cough with viscous
discolored expectoration. Breathlessness develops in
moderate to severe forms. Haemoptysis and chest pain
develop in the phase of exacerbations. Sinusitis is
common in both conditions while pneumothorax and
steatorrhoea----malabsorption are common in cystic
fibrosis . pregnancy carries risk of exacerbations and
fetal IUGR / prematurity.
12. Cystic Fibrosis And Bronchectasis---
Auscultation reveals crackles over affected area.
Diagnosis confirmed by X ray chest . High resolution
CT scanning will confirm . , but this investigation is
deferred in pregnancy.
13. Chronic Obstructive pulmonary
disease (COPD )
It is seen in pregnant women > 35 years of age with
H/O smoking minimum 20 packs per year For 20
years.
main symptom is breathlessness on exertion and
reduced exercise tolerance. , may be accompanied by
morning cough and expectoration . Reduced breath
sounds in all fields with wheeze during exacerbations.
14. Obliterative Bronchiolitis ----
Relatively uncommon and difficult to diagnose.
Clinical and X ray findings are indistinguishable with
those of Asthma. , with small air ways obstruction ,
There may be H/O childhood respiratory illness.
15. Parenchymal and Interstitial lung
diseases
1, Pneumonia---Pneumococcal--- An acute febrile illness
with Chills and rigors ,a short history of breathlessness ,
cough , sticky blood stained sputum , chest pain preceding
common cold .Respond well to high dose penicillin
therapy.
Clinical examination---- Increased respiratory rate
,Bronchial breathing, crepitations , and consolidation
Confirmed by X ray . Mycoplasm pneumonia complicates
HIV disease and its course run for several weeks, x Ray
reveals bilateral interstitial infiltration. Bronchoscopy for
Cytological analysis is some time necessary.
16. Acute Lung Injury Or ARDS -----
Occurs in 0.2-0.3 % cases in pregnancy and may be
secondary to pneumonia , aspiration pneumonitis,
eclampsia ,amniotic fluid embolism . Its diagnosed by
deteriorating condition of patient and worsening X ray
consolidation findings through out both the lung
17. Tuberculosis (TB)-----
TB can cause breathlessness when extensive bilateral
involvement of lung paranchyma is present. H/O
cough , low grade evening rise fever , night sweats,
weight loss, loss of appetite , haemoptysis. Three
samples on consecutive days for AFB , Xray chest
showing consolidation often with cavitations. ATT is to
be continued as in case of non pregnant women.
Breast feeding is allowed if pt is not an open case /
newborn is immunized with Isonex resistance BCG
and prophylactic isonex therapy to child.
18. Pulmonary Metastases
Are rare , can easily be diagnosed by X ray chest ----cannon
ball metastatic infiltration
Symptoms usually develop when multiple lesions are
present .
Breathlessness ,cough , haemoptysis .
Chest auscultation may be normal .
Chorio carcinoma is common tumor with lung metastases
during pregnancy or following evacuation of malignant
vesicular mole / invasive mole.
Pleural effusion is common . , when pulmonary metastases
are present.
The metastases disappear with Chemotherapy following
management of primary lesion.
19. Sarcoidosis--------
It is common in young women of Afro – caribbean origin
and is often severe.
Breathlessness is common when pulmonary infiltration is
wide / enlarged mediastinal lymph nodes press the
bronchus.
Patient also develops cough , weight loss and involvement
of other organs like skin and eyes.
Auscultation of chest may be normal or crackles along with
wheeze may be present.
X ray chest in conjunction with clinical picture , raised
serum angiotensin conversion enzyme .
Bronchial mucosa biopsy with bronchoscope will confirm
the diagnosis.
20. Drug induced Interstitial Lung
Disease
NFT used for long term treatment of resistant /
persistent UTI, can cause severe acute or chronic form
of interstitial lung disease with hypoxia .
Amioderone used in cardiac arrhythmia can cause
acute pneumonitis ( incidence 0.1-0.5 % with dose of
200mg / day ) and subsequent pulmonary fibrosis.
Patient develops breathlessness and cough .
Chest auscultation reveals bilateral basal fine crepts.
21. Lymphangio leiomyomatosis
Rare but occurs in young women of reproductive age.
Clinical manifestation includes interstitial lung
disease , recurrent pneumothoraces .
May be bilateral with tuberous sclerosis.
Chest auscultation may reveal bilateral crackles .
Once suspected , it can be confirmed by X ray and high
resonance CT .
22. Lymphangitis carcimatosa
Occurs in advance metastatic breast carcinoma.
Patient develops profound hypoxia.
Like drug induced interstitial lung disease patient
develops breathlessness and dry cough .
23. Extrinsic Allergic Alveolitis
Relatively uncommon .
Associated with an identifiable trigger antigen , such
as inhalation of Thermophylic Actinomycocetes spores
in mouldy hay ( farmers lung )
Progressive breathlessness , wheeze and cough occurs
with pulmonary infiltrates on X ray chest . , often the
upper lobes .
24. Fibrosing Alveolitis
Associated with auto immune diseases , which occur
frequently in young women .
Auto immune diseases like rheumatoid disease, SLE ,
scleroderma may be associates.
Progressive breathlessness and cough are typical with
fine , late aspiratory crackles on auscultation .
Finger clubbing may be present .
X ray shows bilateral , peripheral , basal interstitial
shadows . HR –CT helps in confirmation .
Lung function studies reveal reduced diffusion
capacity.
25. Cryptogenic Organizing Pneumonia
Also associated with auto immune disease.
Patient develops Acute breathlessness . Cough and
hypoxia.
Parenchyma shadowing is more patchy than fibro sing
alveoli is .
Note --- Chronic nature of some of these interstitial lung
disease may not be compatible with pregnancy .
26. Vascular diseases causing
Breathlessness in Pregnancy
Pulmonary embolism( PE ) is an important cause of
breathlessness, its risk increases as gravidity , maternal age , BMI
increases and LSCS , Family h/o thrombi embolism , DVT , PIH ,
Thrombophyllia , previous thromboembolism , prolong bed rest
, varicose veins, Valvular heart disease etc.
Pregnancy itself is also a major risk factor for Peas it is a state of
hyper coagulation. It is most common cause of maternal death in
developed countries where other causes of MMR are well
controlled.
Patient suddenly develops breathlessness and chest pain . There
may be tachycardia, hypotension , blood stained frothy sputum
and cyanosis in severe cases.
Auscultation may be normal exce3pt increased respiratory rate.
Ventilation /Perfusion (V/Q ) Scanning, X ray chest will help in
diagnosis. Computerized tomographic pulmonary angiography (
CTPA) may be needed when V/Q is in conclusive .
27. Vascular causes of Breathlessness--
-
Amniotic Fluid Embolism
Amniotic fluid embolism is rare occurring in 1in 100
-1000of deliveries.
Presents with sudden onset of breathlessness
during labor or with in 30 minutes of delivery .
There is cardiovascular shock and DIC.
Mortality is 60 -90% . , a major cause of maternal
death during labor.
28. Vascular Causes---
Primary Pulmonary Hypertension
A rare condition usually occurring in young women .
Presenting With breathlessness on exertion.
There may be ankle edema and other signs
of right sided heart failure.
Onset and progression is often insidious and
diagnosis is frequently missed early in course of early
disease.
Ecocardiography will help in diagnostic confirmation
.
29. Vascular causes-----
Secondary Pulmonary Hypertension
Occurs as a consequent of chronic lung diseases or
pulmonary embolism.
Present with similar symptoms and signs.
There can be significant hypoxia with both types of
pulmonary hypertension.
30. Pleural Causes----
Pleural Effusion
Secondary to pneumonia or tuberculosis may cause
breathlessness.
Rare cause of pleural effusion in pregnancy is
chylothorax ( Lymphangomyomatosis ), chorio -
carcinoma , breast carcinoma and other metastatic
malignancies and rupture of diaphragm in labor.
Chest examination will reveal shifting of trachea to
opposite side , dull on percussion, absent breath
sounds . X ray chest will show collapsed lung and
pleural effusion on affected side.
31. Pleural Causes------
Empyema
Findings are same as that of pleural effusion , but
patient will be toxic.
Fluid drained will be frank pus instead of ecxudate.
Pneumothorax
Rupture of Emphysematous bullae is the common
cause .
Often acute in onset , leading to progressive
breathlessness as more and more air is trapped in
pleural cavity more and more lung is compressed. On
chest examination affected side is resonant ., X ray
shows collapsed lung an d air in pleural cavity.
32. Chest wall causes of Breathlessness
Obesity (Body Mass Index > 30 ) frequently leads to
breathlessness and reduced exercise tolerance.
Examination otherwise will be normal.
Kyphoscoliosis, Ankylosing spondilitis and
neuromuscular disorders may cause breathlessness
due to abnormal lung mechanism or paralysis of
diaphragm . Such patients should be investigated for
Partial pressure of arterial blood for evidence of
hypoxia and hypercapnoea
Splinting of diaphragm may occur in pregnancy
complicated by OHSS, Massive acute Polyhydramnios
or plural pregnancy leading to too much distension of
uterus leading to Breathlessness.
33. Metabolic causes---
Anaemia Moderate to severe in pregnancy usually
cause tiredness and decreased exercise tolerance ,
Breathlessness is less common.
Thyrotoxicosis may be present with breathlessness
in pregnancy . Typical features include tachycardia,
weight loss inspite of good diet and appetite, diarrhea,
tremors, insomnia and eye signs .There may be goiter
in neck. Thyroid function test will confirm the
diagnosis.
Acute / chronic renal failure / acidosis and systemic
sepsis can develop breathlessness.
34. Clinical Approach--------
History of Present Illness
1. Onset of symptoms in relation in to timing of pregnancy
2. Duration, chronicity , nature and severity of breathlessness.
3. Exercise tolerance specially in relation to day to day activity .
4. Presence / absence of cough , sputum , haemoptysis .
5 . Relief with inhaler.
6. Palpitation.
7. Chest pain.
8. Weight loss, fever, anorexia , malaise .
9. Leg pain.
1o. Nasal and sinus problem .
11. Sore throat , arthrelgia and myelgia.
35. Past Medical history
Asthma, allergy , hay fever , eczema. Nasal block.
TB, previous BCG vaccination , Cystic Fibrosis ,
Brochiectasis , other lung disease.
Sarcoidosis , Kyphoscoliosis ,Neuromuscular disease,
Ankylosing Spondolitis , Herat Disease , Recurrent
UTI.
Malignancy ( breast ), immunosuppresion (HIV +ve.)
Psychiatric illness.
Previous history of Pulmonary embolism , DVT ,
Thrombophillia . Thyrotoxicosis.
36. Other contributory history------
Drug History NFT , Amioderone , NSAIDs and
inhalers.
Psychology Anxiety or depression . Rx continuing or
stopped ?
Family History Clotting disorder , Asthma , Atopy ,
Lung cancer , TB , sarcoidosis.
Social History Ability to lead normal routine life ,
specially going to work , climbing stairs , doing house
hold work and shopping.
Living in travel to high prevalence and contact TB.
38. Physical Examination-----
Breast any lump / mammography is better.
Neurological muscle wasting , fasciculation's , limb
weakness, sensory loss ,cerebral signs if any .
39. Investigations
RadiologyThe accepted cumulative dose of X ray
radiation to which fetus can be exposed safely is
estimated, ---5 rads.
This is equivalent to n71 thousand X rays , 50 CTPAs , or
3o V/Q scan. It can be concluded that , for most of the
common tests , exposure to radiation is minimal and
lease likely to effect the fetus. In the first instance Xray
chest is crucial to reach the diagnosis like pneumonia ,
pleural effusion , hydro /pneumothorax, tuberculosis
and sarcoidosis .
40. Radiological Investigations----
V/Q scanning is essential to diagnose pulmonary
embolism , an acute life threatening condition.
CTPA is still more important in PE when V/Q is
showing only an intermediate probability of PE , and
the clinical findings are in favor of PE.
HR CT is needed to diagnose bronchiectasis and
interstitial lung diseases., could be avoided till
puerperium , if the clinical outcome is not affected. .
Although ct – is l-safe for fetus but mother also carry
an increased risk of carcinoma breast in pregnancy. A
radiation of 1 red can increase life time risk of breast
cancer as high as 14 % in exposed women at 35 years of
age.
CPTA Delivers 2-3.5 reds to each breast .
41. Investigations----
Lung Function Tests
Forced Expiratory Volume in one Second (FEV1-
)---egg, volume of air blown out in one second .
Forced Vital Capacity ( FVC ),e.g. Total volume air the
subject is able to blow out in one effort ( man oeuvre)
FEV1 / FVC ratio remain unchanged in pregnancy.
Normal Spirometry
FEV1, FVCand FVC1 / FVC ratio performed with simple
hand held spirometry, if normal will exclude any
obstructive lung disease like asthma , cystic fibrosis ,
bronchiectasis and COPD .
42. Lung Function Tests ------
Low FEV1 /FVC ratio < 70% low FEV1 <80% and a
characteristic ‘ scooped out flow curve “ indicates
obstruction to the small air ways .
Significantly narrowed ‘ aspiratory flow volume Loop”
indicates dysfunction vocal cords.
Most extensive lung functions like Diffusion capacity (
transfer factor ) and static lung volumes are important
to diagnose interstitial lung diseases.
Finger attached Asymmetry (on 6minutes walking)
helps in diagnosis of unexplained breathlessness
indicating how far the patient can walk , and whether
or not there is any significant respiratory disorder if
there is no fall in O 2 saturation.
43. Investigations---
Blood Tests-
Hob , WBC , Urea ,Electrolytes , Thyroid function tests
, D-dimmers ( negative D-Dimmers effectively exclude
PE.) Positive D-dimmers increase in pregnancy and are
not significant and may be raised in infections also.
Significant low PaO2 occurs in these conditions .
44. WHEN TO CALL Respiratory
Specialist?
1, Unduly troublesome breathlessness.
2, Worsening breathlessness.
3, Acute breathlessness.
4, Abnormal Chest X ray / spirometry.
5, Uncertainty regarding diagnosis.
6, When CT of thorax is indicated.
7, When detailed lung function tests , such as diffusion
capacity , static lung volume , or walking oxymetry is
needed.
8, Uncertain about performing / interpreting spirometry.
45. Summary
Breathlessness in pregnancy is more due to
physiological changes, but can be differentiated from
pathological condition by detailed history clinical
examination and X ray chest.
Simple lung function can be done if necessary, to
exclude important respiratory conditions .
