Lecture 11 Oct 25th-respiratory

October 25th, 2006 Respiratory conditions Conditions of the respiratory system Insidious onset=How a condition started is unknown NAD=No Acute Distress (circulatory, systemic, respiratory) PND= Paroxismal Nocturnal Dyspnea Chronic Bronchitis/lung cancer not about how long patient has smoked (ie. 1/2 pack/day for 20 years) but how much they smoke (50 packs/year for 3 years) 3 pillow orthopnea: sleeps with 3 pillows in order to be able to breathe Case 2: 58-year old woman with insidious onset chronic cough of 3 month duration. Cough keeps waking her up at night. She is currently unemployed, lives in cooperative housing (subsidized) with boyfriend. She is reliable, interacts well, NAD, W/N Px denies SOB on exertion, weight loss, fever, diarrhea, anorexia, bouts of confusion or memory loss. Smoker, 20 pks/year, PND and 3 pillow orthopnea. Physical exam: Height: 163 cm Weight: 142 lbs BP: 151/98 68 bpm 37.3 C 14 rpm No central/peripheral cyanosis, no clubbing, no delayed capillary refill. No rales bilaterally, + rhonchi, + expiratory wheeze, clear to percussion. What is going on? Do you need to ask more questions? Why? Are there any red flags in this case? How would you manage this case in your office? Ddx. Lung cancer (no fever, chronic cough) • •

Chronic bronchitis (more gradual onset) history says, no probably not 3m, probably 5-10 years. Also, CB lets you sleep at night. Takes >3 months to develop. Emphysema (takes >3 months to develop), not disturbing because it has a gradual onset.

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Remember that there can be many things happening at the same time (eg. Chronic bronchitis, lung cancer) How long has the patient been living in a co-op? Might be mold. NOTE: Pathology is not on exam LARYNGOTRACHEOBRONCHITIS (CROUP) • Abnormal malformation of glottis ACUTE EPIGLOTTITIS • Can be fatal: must go to hospital • Not good if not intubated PERTUSSIS (WHOPPING COUGH) • Happens to children and adults • Typically builds up and may end with vomiting • Scary to see: the patient can’t get enough air. • www.whoopingcough.net/symptoms.htm Can listen to sounds. • After bout, patient is fine. • Respiratory distress always requires action. • Coughing can cause hemorrhage (eg. in conjunctiva) • If you are new to practice and haven’t seen this a lot, have someone else involved that HAS seen it a lot. • Antibiotics do not affect course of disease • Contagious • Note: afebrile for DDx ASTHMA • Inflammatory disorder characterized by: • Hyperactivity of immune system (to dust derivatives, smoke) • Air flow obstruction • If not addressed, inflammation will produce fibrosis of lung. • Most children with asthma improve during adolescence. • Hypochlorhydria (low stomach HCl) may be contributing problem (improper digestion?) • Pthophysiology is very important in asthma. • Exposure to allergen local mediator release inflammatory compound release local constriction of smooth muscle chemotaxic factor release epithelial and neural damage widespread effect. • (from list above: inflammatory compound release also causes increase capillary permeability)

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If the immune response is engaged with 1 thing, others may get through, leading to pneumonia (squawk that precedes crackle: sounds like a chicken) Chest X-ray for asthma: history is important (patient coughing?). o In a normal chest x-ray, rib markings are visible o In asthma attack, no rib markings can be seen o Lung is hyperinflated o Diaphragmatic margin pushed down due to inflated lung. In asthma, problem is with exhalation, during acute attack. Sputum is produced because the immune system thinks you have an infection Important to know red flags, to be comfortable managing an asthma case. Disappearance of wheeze: patient may not be breathing anymore Red flags are missed all the time because the doctor’s belief in the treatment blinds them to patient symptoms Good way to assess treatment is with a peak flow meter. Should be above 70%. Asthma causes serious damage, people die form untreated asthma. Take it very seriously. Usually, asthma attacks are not concerning. Red flags are very concering. Do no harm = death. Have epinephrine for auto-injection, emergency medications on hand. Many things look like asthma, it is very difficult to diagnose. Best to test breathing capacity, give patient a dose of universal irritant. Patient’s FEV will be reduced by more than 20% after challenge. Every time a provocation test isn’t done = misdiagnosis Children can compensate a lot, loss of symptoms may not mean 70% PFR, important to manage case properly, even if PFR is 80-90%

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Important to coach /encourage patient during use of spirometer for assessment.

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Normal lungs exhale most of the air in 1st second. Not measuring force, but amount of air.

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PFM: Peak flow meter: measure speed of air. Done with asthma.

Confirmatory evaluation: Do bronchial lavage when REALLY confused. TB cells, cancer cells, show up in bronchial lavage. ELISA can be done if looking for disease This type of evaluation: not really part of DDx. Need to understand DDx on its own. If the test won’t affect the management of the condition, it may not be worth it to do the test. Better to ask for opinions, not tests (invasive). (PFT is the same as spirometry. PFT is a better term.)

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Difference between obstructive and restrictive pulmonary disease is usually on NPLEX. ACUTE BRONCHITIS • Should go away in about 3 weeks. • Cold, cough • Rhonchi sounds bubbly or gurgly. • Crackles: alveoli that are closed, opening with a “snap!” • Obstruction due to infection BRONCHIECTASIS • Sputum, pus accumulates. Lung fills up when patient stands • Needs to be resolved/cured, not “managed”. • Causes irreversible destruction of bronchi/alveoli • Can lead to respiratory failure. COR PULMONALE • Capillaries are “narrow sieve” that blood goes through to lungs • Heart tries to help, increases BP • Pulmonary hypertension occurs • Right heart having trouble, left okay. Right ventricular problem. • Asthma can lead to bronciectasis death • Eventually get left ventricular failure because LV compensates by sucking harder • On CXR: see whiteness (should be clear), pus and fibrosis all over TUBERCULOSIS • On the rise in Canada • “creeps up” on patient: slow onset • Patient comes to doctor because they have a general feeling of ill health • Easy to miss: important to know risk factors • With alcoholism, cilia not beating properly • Look at history: tree planting is risk factor • Generally patient has a clue in their history (exposure) and has a weakened immune system • Can be associated with community health centres • • • •

TB incubates inside host cell. Multiplies. Immune system realizes, but the pathogen is now encapsulated. Immune system expends energy (calories) to get to TB inside capsule, but TB is safe, continues to multiply. Patient experiences weight loss Most of us have already been exposed to TB. Can be tested to make sure that we don’t have it. If well nourished, can fight it. Be competent in what your community tends to present with

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Cough for >2 months? Screen for TB. Mantoux test (indirect assessment) TB is Type IV hypersensitivity Can exist in eye in unexplained clear/light spot.

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