Doencas Pulmonares Obstrutivas Flashcards
Doenças incluídas neste grupo
- DPOC
- Asma
- FQ
- Bronquiectasias
- Doenças bronquiolares (pequenas vias)
Sintomas que podem ser comuns
Sibilância, expectoração, inflamação crónica das vias aéreas, alterações estruturais e remodeling, exacerbações
asma e DPOC
- DPOC: inflamação e estrutura das vias aéreas anormais em resposta a um irritante inalado (tipicamente fumo de tabaco)->limitação fluxo ar irreversível ou incompletamente reversível. Tipicamente PROGRESSIVA.
- Asma: hiperreactividade do músculo liso com limitação do fluxo aéreo REVERSÍVEL, curso clínico variável e associação frequente com atopia
Sintomas típicos bronquiectasias (3)
Tosse crónica, expectoração purulenta, hemoptises
O fluxo de ar que passa nas vias aéreas é directamente proporcional à ‘driving pressure’ é inversamente proporcional à resistência. Que processos estão alterados na asma e DPOC?
DPOC: - elastic recoil in expiration .: - driving pressure
Asma: + resistência pela contração do ML, inflamação e fibrose, colapso pequenas vias (por perda do tecido pulmonar circundante)
Produção de muco (+resistência) em todas as doenças obstrutivas
Alterações espirométricas
RV e FRC aumentados
TLC =/aumentado
Capacidade vital reduzida
Capacidade inspiratoria reduzida
Exame Dx útil para # asma de DPOC
FEV1/FVC pós broncodilatador
Melhora na asma
DLCO na asma e na DPOC
Asma: normal ou aumentado
DPOC: diminuído
Sintomas FQ
Sinusite, bronquiectasias, ileus meconial, má absorção, infertilidade (em homens, ausência congénita do canal deferente)
Hx possível de outras doenças associadas a doenças bronquiolares
Doenças do tecido conjuntivo, DII, tx pulmonar ou de células estaminais hematopoiéticas
Alterações Rx doenças bronquiolares
HRCT: Padrão mosaico, nódulos centrilobulares, ‘tree in bus’ opacities
Microorganismos frequentes em doentes com FQ
Haemophilus Inf.
Pseudomonas
Micobactérias atípicas
Exames Dx FQ
Conc. Cl aumentada no suor
Mutação gene CFTR (canal cloro)
potencial da mucosa nasal anormal
Gordura fecal aumentada
Definition of COPD
Persistent airflow limitation that is usually progressive and ~ with enganches inflammatory response.
Note: emphysema and chronic bronchitis are not synonyms with COPD (they can occur with or without expiratory airflow limitation)
Pp 208, C16
Definition of chronic bronchitis
Cough and sputum for at least 3 months in at least 2 consecutive years
Factors associated with increasing prevalence of COPD
Age, lower sociodemographic status, smoking, men
Pp 208, C16
Which position does COPD hold as a cause of death worldwide
4th
Pp 209, C16
Only genetic disorder ~ COPD
Alfa1-antitrypsin deficiency (1-2% of COPD cases)
Note: there are familial clusters
Average lung function decline in:
a) non-smoking men
b) smoking
c) susceptible smoker
(Decline in FEV1)
a) 35-40 ml
b) 45-60
c) 70-120
Definition of emphysema
Permanent enlargement of the air spaces distal to the terminal bronchioles
Pp209, C16
Classification of emphysema
Centrilobular (most common in emphysema related to smoking) and Panlobular (Alfa1-antitrypsin deficiency)
main target for inactivation by antitrypsin
Neutrophil elastase
Cigarette smoke contains a lot of oxidant molecules capable of oxidative stress. What are the effects of this?
Inactivation of antiproteases, acetylation of specific histones in the chromatin of lung cells (with the expression of pro-inflammatory genes)
Where is antitrypsin produced?
Liver
Therapies targeted at molecular pathways involved in emphysema pathogenesis have not been successful in disease progression except…
Antitrypsin replacement in patients with its deficiency (decreased loss of lung density)
Predominant symptom in chronic bronchitis
Sputum production
Symptoms and signs of COPD (clinical presentation)
Symptoms: Slowly progressive dyspnea, exercise intolerance, fatigue, weight loss, depression, anxiety, chronic cough (productive or dry).
Physical examination: may be normal initially. Hyperresonance, diminished breath sounds, ronchi or wheezes, barrel chest.
Later stages: increased work of breathing and weight loss.
Pink buffer vs blue bloater phenotype
Pink buffer: able to retain normal O2 levels until very late.
Blue bloater: retain CO2 and diminish work of breathing resulting in chronic respiratory acidosis.
Most important triggers of exacerbation sim COPD
Infections, air pollution, pulmonary embolism, cardiac failure
Pp 211, chap 16
Comorbid conditions associated with COPD (4)
Atherosclerotic heart disease, lung cancer, osteoporosis, depression
Pp 211, chap 16
Signs of cor pulmonale
S3, distended neck veins, hepatojugular reflux, leg edema
Pp211, chap16
The severity of COPD depends on the FEV1. What are the 4 stages ?
GOLD 1: FEV1 >=80% predicted
GOLD 2: >=50% but less than 80%
GOLD 3: >=30% but less than 50%
GOLD 4: <30% predicted
What scale is used for a better prediction of mortality in COPD?
BODE index
(BMI, FEV1, dyspnea score, exercise capacity in 6-minute walk)
Pp 212, chap 16
Apart from FEV1, what other tests can be used in COPD?
Lung volume (increased RV, FRC and TLC), DLCO (decreases), Chest x ray (hyperinflation, hyperlucency, flattening of diaphragm, bullous changes in parenchyma), CT (Dx of emphysema in patients considered to operative interventions) HRCT (more sensitive for occult emphysema and emphysematous changes), ECG (RV strain), echocardiography (RV hypertrophy or dilation, pulmonary arterial pressure), high blood hemoglobin level