Asthma Chapter 3

Asthma

diffuse airway inflammation, narrowing in response to various stimuli..ENTIRELY OR PARTIALLY REVERSIBLE

status asthmaticus

asthma attack that does not respond to conventional tx

occupational asthma

bronchospasm, in response to provoking agent in the work place

stable asthma

4 weeks, no increase in symptoms or need for an increase in meds

unstable asthma

pt experiences increasing symptoms

Most common trigger of asthma attack

infections

triggers of asthma

Allergy(Mold, dander), Irritants(smoke, perfume pollution, chlorine), Resp. infection, cold air, reflux and medications

lack of uniform ventilation caused by??

combination of bronchospasm, mucus plugging, and mucosal edema>>>INCREASED AIRWAY RESISTANCE

V/Q

the result of vascular resistance...V/Q mismatch results in hypoxemial

pulmonary vascular resistance increases as a result of

hypoxemia

initially ariway obstruction primarily effects??

exhalation..results in air trapping and progressive hyperinflation of the lungs

increases the work of breathing??

combination of increased airway resistance and lung hyperinflation

acute asthma attack complaints??

chest tightness, dyspnea, wheezing and coughing

confirm the dx from

pt's age, medical hx, physical findings, xray, lab tests

Common findings with asthma

tachypnea, use of accessory muscles of breathing, prolonged exhalation, increased A/P diameter, expiratory polyphonic wheezing, diaphoresis and intercostal retractions.

Severe asthma suggested by??

pronounced use of accessory muscles, abnormal sensorioum paradoxical pulse, tachypnea, inablilty to speak and wheezing on inhalation and exhalation

Signs of fatique

decreaseing peak flow, diaphoresis and abdominal paradox(inward movement of ab walls during inpiration from fatigue of diaphragm.

peak flow suggesting severe obstruction

less than 100 liters/minute or an FEV1 of less than 1.0 L in an adult

Methacholine provocation

used to provoke bronchspasm...for testing..Asthmatics will have greater than 20%decrease in FEV1 in response to methacholine, normal pt.s have little or no response

Mild asthma

Normal PO2, decrease CO2, increase in pH..Increased Respiratory rate, blowing off CO2(acid) increasing pH towards alkaline

Severe asthma(status asmaticus)

decrease in PO2, normal or increasd CO2(retaining, because narrowing of airway, can't get CO2 out), making pH normal or decreased, towards 0 (ACID)

Immunoglobulin E (IgE)

plays role in pathogenesis of allergic diseases, such as asthma

Anatomical alterations

smooth muscles, small airways constrict, increases 3X's it's normal size, airways filled with mucus, plugging

CC of asthma

chest tightness, difficult breathing, wheezing, coughing

Can be seen in a physical exam

tachypnea, accessory muscle use, PROLONGED exhalation, Increased AP Diamater, Expiratory polyphonic wheezing, diaphoresis, intercostal retractions

Status asthmaticus physical exam

pronounced use of accessory muscles, paradoxial pule, inability to speak, I and E wheezing, decreased peak flows, diaphoresis, abdominal parox and abnormal sensorium

CHEST XRAY

Often normal, but can see hyperinflation...and Pneumonia, Atelectasis, and Pneumothorax

refractory

whatever tx you do, conventional, it doesn't work

Treatment

educate pt, determine severity, use a bronchodialator and control meds

sputum with asthma

white, tenancious(sticky), thick

Peak Flow readings

Green zone 80% or higher..Yellow zone 50-80%, Red zone less than 50%..based on pt's age, height, and sex

PEFR

peak expiratoyr flow rate

Extrinsic asthma

allergic asthma, excessive IgE in body, mast cell degranulation..causes constriction..exploding release of histamines

Meds for extrinsic astma

Xolair and singulair

IgE

natural, found in body, excessive in pt's with allergic asthma

Omalizumab(Xolair)

anti IgE medication

Leukotriene

released from mast cells, eosinophils and basophils, lead to increased inflammation

Leukotriene modifier

singulair.,.usually added with a bronchodialator

Nocturnal asthma

12pm-4Am, GERD(micro aspiration of stomach contents, reflux), Allergin exposure(dust mites), temp change in body, delayed exposure to allergins from the day, low cirulation of adrenal gland hormones

occupational asthma

animal substances, chemicals enxymes, metals plant substances, resp. irritants

intermittent

<2 x's week, normal PEFR between..No meds

mild persistent

>2x's week but , 1/day...inhaled antiinflammatory

moderate persistent

Daily symptoms, inhaled steroids and long acting bronchodialator

severe persistent

limited physical activity, frequent exacerbations, oral and Inhaled steroids +everything else

5 Classifications of Asthma

Extrinsic(allergic), Intrinsic(non-allergic), Exercise-induced, Nocturnal and Occupational

Immediate attack

usually resolves within 1 hr of exposure

Late attack

happens within hours of exposure, lasts longer

biphasic attack

combo of Immediate and Late attack

Intrinsic Asthma

nonspecific stimuli..rhinovirus and URI, are triggers.

nonspecific causes of intrinsic asthma

exercise in cold dry air, drugs, foods, relux, Stree, premenstral, smoke, heriditary, obesity

Exericse induced asthma

poor athletic performance, long recovery time after exercise, fatigue furing exercise, coughing, wheezing, chest tightness or pain, SOB,

Bronchospasm,<mucusplugging,mucosal edema

increased airway resistance leads to V/Q mismatching leads to hypoxemia leads to Increased pulmonary vascular resistance