Bronchial asthma

Bronchial asthma is a syndrome characterised by increased responsiveness of trachea and bronchi to various stimuli and manifested by acute, recurrent or chronic attscks of widespread bronchial-bronchiolar narrowing, variable in severity and usually of brief duration. It is believed that airway reacitivity is the major feature of asthma and this is induced by inflammation and that inflammation is the basic abnormality present in asthma.

Classification:

1. Extrinsic asthma -- applies to those who produce excessive lgE in response to allergens (atopic).

2. Intrinsic asthma -- refers to those cases in whom excessive lgE production cannot be demonstrated (non-atopic).

Inducers and triggers of asthma

Inducers of asthma -- After birth, several factors interact to result in the clinical manifestations of asthma. Factors called inducers actually switch on the asthma following which symptoms may be present for weeks, months or years. These factors are:

1. Viruses -- Childhood virus infections are important inducers of asthma. 5-50% of children wheeze following respiratory syncitial virus (RSV) bronchiolitis. Also parainfluenza and influenza virus infections. Bacteria that can induce wheezing are pertussis and mycoplasma.

2. Cigarette smoke -- It is known that if parents smoke during the first two years of their child s life, the child is likely to develop asthma.

3. Allergens -- The influence of both genetic and environmental factors is important and asthma is a complex response to a variety of stimuli, making it difficult to identify specific factors. (a) Aero-allergens (inhalants) -- Exposure to aero-allergens such as house dust, mite allergens, tree pollens, feathers, paint, smoke, animal dander, moulds. (b) Ingestants -- Milk, eggs, nuts, chocolates, fish, shell-fish, strawberries, etc.

Triggers of asthma -- cause an attack of asthma which usually lasts only for minutes or hours. They trigger symptoms once the tendency is already there: a)Exercise especially running. (b) Laughing, coughing. (c)Emotional factors ranging from pleasurable excitement in children to stress or worry in adults. (d) Change of weather such as sudden changes in temperature, fog, wind. (e) Drugs -- Beta-blockers such as propranolol or alpha-blockers e.g. phenxybenzamine.

Asthmatic attack:

(1) Premonitory symptoms "asthmatic aura" -- Sometimes sneezing, flatulence and drowsiness, or restlessness and irritability. Dry irritant cough may precede or accompany attacks of wheezy breathlessness.

(2) Paroxysm -- Usually sudden in middle of night. Sense of oppression in chest going into respiratory distress. Patient sits up and leans forward fighting for breath, or runs to window to relieve sense of suffocation. Anxiety, cyanosis, perspiration and cold extremities. Wheezing may be heard at a distance. On auscultation -- inspiration short and high pitched, expiration prolonged, plenty of rhonchi. Rales may be heard at the bases towards the end of an attack. However, in very severe airways obstruction airflow may be so reduced that the chest is almost silent. Tachycardia especially in children.

(3) Termination -- Spontaneously or as a result of therapy. As bronchial spasm gets less, patient is able to cough a little and may bring out viscid muco-fibrin.

(4) Duration of attack -- Varies from few minutes to several hours. Sometimes paroxysms are continuous -- status asthma .


In traditional Chinese medical studies, clinically, this disease belongs to the category of xiao (wheezing) and chuan (dyspnea- difficultness in breathing). Our motherland medicine consider that weakness of sleen and its Qi (energy) insufficiency, causing hypofunction and decreased of nutrition absorption, reversely, it will yield phlegm thus the phlegm will cause lung and Qi blockade which resulted in lots of phlegm and dyspnea , struggle between phlegm and Qi, wheezing sound in throat and insufficiency of kidney Yang that will cause abnormal sweating; the lungs regulates Qi, accumulation of irregular solid Qi, decreased movements of diaphragm, as a result, it yields dyspnea in lying position and even in sitting position. The lungs regulate or host Qi while the kidneys as the root of Qi, therefore, kidney weakness will cause the Qi cannot conclude at the kidney, so one will has expiration more than inspiration and breathing difficulties; Qi as the main element of blood, if Qi is enough it is able to regulate blood but in contrary if Qi is weak it will cause stagnant of blood, lack of Yang Qi causing bruise immediately, cyanosis of lip and fingernails, dilatation of neck veins (jugular veins); improper Qi affect the normal blood, lose of positive Qi, internal injury of essence of blood, therefore there are possibility to cause respiratory acidosis, regenerative failure and insufficiency of Yang Qi.