Respiratory Flashcards
Asthma meds are aimed at
flattening the response to inflammatory mediators
Why is it that steroids that work in asthma have minimal response in COPD?
Because the inflammation in COPD is of a different pathway than that of asthma
Inhaled _________ can help reduce the frequency of COPD exacerbations
corticosteroids
This type of medication has only a modest ole in increasing air outflow in a patient with COPD with chronic breathlessness that is worsened by exercise
Bronchodilators
So basically in COPD, bronchodilators don’t really help and the steroids used in asthma don’t really work either. People with COPD are placed on corticosteroids.
R sided heart failure with COPD
Those with CB experience R HF and cor pulmonale as part of the disease process
Those with emphysema experience R heart problems during acute infections
Pink puffers refer to __1___
Blu bloaters refer to __2__
1= emphysema 2= CB
PaCO2 in COPD
High in CB
Normal in emphysema
Types of bronchodilators used
Beta agonists
Anti-cholinergics
Methyxanthines
Problem with using epi for treatment of bronchoconstriction
It has B1 and alpha effects as well, which can cause tachycardia, palpitations, and vasoconstriction
Selective B2 agonists
(Short and long acting)
Short acting: - Terbutaline - Albuterol - Levalbuterol (the most B2 selective!) - Salbumatol ^^ We go for the first three of these because we can repeat the dose multiple times
Long-acting
- Salmeterol (pts on this at home and use albuterol for acute attacks)
- Formoterol
All of these B2 selective agents have an affinity for B2 200-400 times stronger than that for B1.
What happens at high doses of B2 selective agents?
They become less selective and start affecting other receptors
Effect of B2 agonists on electrolytes
Hypokalemia**- increased uptake by skeletal muscle. Also there is release of glucose, causing an insulin spike, driving K+ into cells. Also, B2 stimulates the Na/K pump, further driving K+ into cells.
Hypomagnesemia
Hyperglycemia
3 beneficial effects of B2 on the bronchi
Smooth muscle relaxation / bronchodilation
Decreased release of histamine from mast cells
Increased ciliary clearance of mucus
Onset of action of B2 agonists
15-30 minutes
Levalbuterol may act as soon as 5 minutes
How are B2 agonists given?
Inhaled, nebulized, aerosolized, powder, orally, SQ
Only B2 agonist that can be given SQ
Terbutaline
Side effects of B2 agonists
Muscle tremor (B2) Increased HR (B1) Vasodilation (B2) Metabolic changes (B2)- hypokalemia, hyperglycemia, and mypomagnesemia
How can B2 side effects be minimalized?
Inhalation delivery (decreases systemic effects by keeping it in the lungs)
Albuterol dosing
100cmg/puff
2 puffs Q4-6 hours
Nebulizer dose: 2.5-5 mg in 5mL of saline
Albuterol DOA
4-8 hours
Albuterol has an additive effect with _______ on bronchomotor tone
Anesthetics
2 Isomers of albuterol
R- This is Levalbuterol and is more B2 selective
S- This type of albuterol has more affinity for B1
How to blunt airway hyperresponsiveness prior to anesthesia
4 puffs of albuterol
or
2 puff albuterol + 1mg/kg of lidocaine IV
Bitolterol
B2 selective agent that resembles albuterol but is longer lasting.
CV side effects are rare
Dose is 270mcg/puff
Max of 16-20 puffs/day
SQ use of terbutaline
SQ use resembles the effects of epinephrine.
Used for status asthmaticus or pre-term labor
Dose for adults in .25mg SQ Q 15 min
Dose for peds is .01mg/kg SQ
Terbutaline inhaler dose
200mcg/puff
Max of 16-20 puffs/day
How can terbutaline be administered?
Inhalation
SQ
Oral
How do long-acting B2 agonists work?
They have a lipophilic side chain that resists degradation. Results in a DOA of 12-24 hours. These are not used for acute attacks.
How can the amount of time between asthma flare-ups be avoided?
Combined therapy of a long-acting B2 agonist and a steroid
Methylxanthines are also called ______
Phosphodiesterase inhibitors
What is the MAJOR PREVENTATIVE treatment for patients with asthma?
Inhaled corticosteroids
This is the most important type of drug in the management of asthma
Inhaled corticosteroids
Do corticosteroids cure asthma?
No. They are used as a supportive therapy, not a cure.
The degree of bronchoconstriction and hyperresponsiveness in asthma paralleles _____
the degree of inflammation
Asthma is characterized by these two features
Inflammation and hyperresponsiveness
Effect of using corticosteroids with a B2 blocker
It increases the DOA of the B2 blocker
Effect of eosinophil degranulation
Interferes with the activity of M2 receptor, causing bronchoconstriction
Salmeterol is given as a combination of
Salmeterol and fluticasone
These are the most important drugs in asthma management
Corticosteroids
These are the most important drugs in COPD management
anticholinergics (tiotropium is best –> only FDA approved anticholinergic for COPD).
Tiotropium has minimal SE because it doesn’t cross the respiratory epithelium
Methylxanthines (phosphodiesterase inhibitors) interact with this anesthetic
Halothane
How long does it take for cromolyn to take effect? How does cromolyn work? What are the SEs?
It is a mast cell stabilizer (inhibits antigen-induced histamine release). It is for preventative therapy only!!! Takes 7 days for effect to kick in.
Montelukast (Singulair) can interact with ____ and cause ______
Warfarin
Prolonged PT
The Anti-IgE antibody we know if called
Omalizumab
Nerves that aren’t part of the ANS can release these substances to induce bronchiole dilation
NO and VIP
