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Treatment of Status asthmaticus
Propped up position.
Oxygen inhalation by mask
Injection Hydrocortisone 200-500mg I/V routes 6 hourly Or Sodium succinate.
Nebulizer – over 5 minute repeated in 15 minutes.
Injection adrenaline subcutaneously 0.5mg (1000 dilution) 1:1000ml.
Ipratropium bromide ( 0.5mg should be added in nebulizer)
Injection Aminophylline ( 5 mg/kg intravenously very slowly)
If improved this condition then oral prednisolone 30.-60mg daily with inhaler sulbutamol.
Antibiotics if necessary.
No sedative of any kind.
Chest X-ray to exclude pneumothorax
Treatment on discharge:
- Complete the course of antibiotic
- Short course of oral prednisolone
- Inhaled beta agonist + inhaled steroid
Treatment plan of chronic asthma
It is also called step care management of Asthma.
Step – I : Occasional use of inhaled short acting β2 agonist bronchodilator ( once daily)
Step – II: Regular inhaled anti-inflammatory agent ( Chromolin or low dose leukotrien antagonist)
Step – III: Regular inhaled corticosteroid + regular long acting inhaled β2 agonist
Step – IV: High dose of inhaled steroid & regular bronchodilator
Step – V: Best of step + oral prednisolone
Bronchodilators administered by inhalation\
- Salbutamol
- Sulmeterol
- Formeterol
- Albuterol
- Isoproterenol
- Metaproterenol
- Terbutaline
- Ipratropium bromide
- Dexamethasone
- Beclomethasone
- Budesonide
- Flunisolide
- Di – sodium chromoglycate
- Fluticasone
- Triamcinolone
Approaches of bronchial asthma treatment:
- Prevention of exposure to allergens
- Reduction of bronchial inflammation and hyper reactivity
- Dilatation of narrowed bronchi
Drugs used in Bronchial asthma
A. Bronchodilators:
1. Sympathomimetic drugs:
a. Selective β2 agonist.
Short acting (duration 4-6 hrs) –
- Salbutamol
- Terbutaline
- Metaproterenol
Long acting (duration 12 hrs or more) –
- Salmeterol
- Fenoterol
- Formeterol
- Rimeterol
- Bitolterol
b. Non selective (β1 & β2)
- Adrenaline
- Ephedrine
- Isoproterenol (Isoprenaline).
2. Methyl xanthene group:
Natural –
- Theophylline
- Theobromine
- Caffeine (also used in neonatal apnoea)
Synthetic –
- Aminophylline. (Na salt of Theiophylin)
3. Antimuscarinic bronchodilator:
B. Anti-inflammatory
1. Corticosteroids:
- Hydrocortisone. (Inj.)
- Prednisolone. (Oral)
- Beclomethasone
- Budesonide
- Triamcinolone
- Flunisolide
- Fluticasone
- Mometason
2 . Mast cell stabilizer:
- Nedocromil sodium
- Cromolyn sodium ( disodium chromoglycate) drugs
C. Others:
1. Leukotrine pathway inhibitor –
- Zileuton
- Zafirlukast
- Montelukast
2. Calcium channel blocker –
- Nifedipine
- Verapamil
- Amlodipine
3. Anti IgE monoclonal antibody:
4. Histamin (H1 ) receptor blocker:
Bronchial asthma:
Asthma may be defined as a disorder characterized by chronic airway inflammation and increase airway responsiveness resulting in
sign of wheeze, cough, chest tightness & dyspnoea.
Pathophysiology of bronchial asthma:
Occurs due to external stimulus, such agents are –
- Biological agents
- Environmental /chemical agent
- Virus
Immunopathogenesis of Bronchial Asthma:
- When a person exposed to antigen it stimulates production of antibody ( reaginic antibody – IgE) and bound to mast cell surface.
- When re-exposure to that antigen than antigen –antibody reaction occur and triggers release of some chemical mediators from stored granules of mast cell and also helps in the synthesis and release of other mediators.
Types of bronchial asthma:
There are various types of bronchial asthma.
1. Asthma associated with specific allergic reaction:
Criteria:
- Very early onset.
- Extrinsic type.
- Atopic individual.
Avoid of allergens – we prevent asthma. Here type I reaction occur involving IgE Antibody.
2. Asthma not associated with known allergy:
Criteria:
- Late onset.
- Intrinsic type.
- Non-atopic. (Not individual) occurs in a group.
3. Exercise induced asthma: Criteria: Within a few minutes asthma develops.
4. Asthma associated with chronic obstructive pulmonary disease.
- Chronic bronchitis
- Pulmonary emphysema
Asthma may also be classified into:
1. Intermittent
2. Persistent –
3. Acute
- Mild
- Moderate
- Severe ( Status asthmaticus)
4. Special variant –
- Seasonal
- Drug induced
- Exercise induced
- Cough variant and Pregnancy asthma
Drugs Used in Benign Enlargement of Prostate
Principle:
Capsular and stromal tissue of Prostate gland is rich in α1 adrenoceptors, and glandular tissue under the influence of androgens. Both these, the α receptors and androgens, and androgens, are targets for drug therapy. Because the bladder itself has a few α receptors, it is possible to use selective α1-blockade without affecting bladder contraction.
Drugs:
α –adrenoceptor blockers:
- Prazosin
- Alfuzosin
- Indoramin
- Terazosin
- Doxazosin
- Tamsulosin
All are selective for α1 receptor.
Others:
Mechanism of drugs used in BHP:
α1 receptor blockers cause significant increases (compared to placebo) in objective measures such as maximal urine flow rate and drugs also improve semi-objective symptom scores. In normotensive men, falls in blood pressure are generally negligible; in hypertensive patients, the decline in pressure can be regarded as an added bonus.
Tamsulosin is a competitive α1 receptor blocker with a structure quite different from that of most other α1 receptor blockers. Long half life of 9-15 hrs. it has higher affinity for α1A and α1D receptors than for the α1B subtype.
Advantages of tamsulosin over other alfa receptor blockers:
- Long half life
- Greater potency in inhibiting contraction in prostate smooth muscle versus vascular smooth muscle
- Drug efficacy in BHP suggests that the α1A subtype may the most important alfa subtype mediating prostate smooth muscle contraction.
- Less effect on standing blood pressure
Adverse effects:
- Dizziness
- Asthenia
- Nasal stuffiness
But Tamsulosin has fewer side effects.
Finasteride:
An alternative drug is the type II 5α-reductase inhibitor; it inhibits conversion of testosterone to its more potent metabolite, dihydrotestosterone. It doesn’t affect serum testosterone, or most non-prostatic responses to testosterone. It reduces prostatic volume by 20% and increases urinary flow rates by a similar degree.
Drug used in erectile dysfunction:
- Sildenafil
- Tadalafil
- Vardenafil
Sildenafil
Mechanism of action:
Erectile response mediated by release of nitric oxide (NO) from nerves supplying vessels in corpora cavernosa. This increases intracellular cGMP levels which cause vasodilatation. Effects terminated by phosphodiesterase type 5 enzymes. Which is inhibited selectively by sildenafil, which enhances vasodilatory action of NO.
Contra indications:
- Severe hepatic impairment
- BP<90/50 mmHg
- Recent stroke or MI
- Patient who are taking organic nitrates
Adverse effects:
- Headache
- Flushing
- Dyspepsia
- Nasal congestion
- Green / blue tingling of vision (3%)
Drugs used for osteoporosis:
- Alendronate
- EtidronateIbandronate
- Pamidronate
- Risedronate
Drugs for obesity:
- Orlistat
- Phentermine
- Sibutramine