Pharm Exam 2 Part 3.txt

is composed of mucus mixed with inflammatory cells, cellular debris, polymers of DNA and filamentous (F)-actin, and bacteria

Mucus is usually cleared by airflow and ciliary movement, and sputum is cleared by

Purulent, green phlegm is caused by the neutrophil-derived enzyme myeloperoxidase, indicating neutrophil activation; this sputum contains very little mucin and can be considered

is defined clinically as daily sputum expectoration for 3 months of the year for at least 2 consecutive years, usually in a tobacco smoker or ex-smoker.

there is hyperplasia of submucosal glands and goblet cells. The number of goblet cells increases, and there is hypertrophy of the submucosal glands, as measured by the Reid index of gland-to-airway wall thickness ratio

is considered the most important predisposing factor to airway irritation and mucus hypersecretion, but other factors can include viral infections, pollutants, and genetic predisposition.

Mucus hypersecretion can occur during an acute asthmatic episode or can be a chronic feature of asthma accompanying airway inflammation. Turner-Warwick and Openshaw51 reported that as many as 80% of patients with asthma report

In actue, severe, and fatal asthma patients have received large amounts of beta-agonist bronchodilators, sometimes even by the intravenous route, it is likely that beta receptors are fully saturated. beta agonists may induce the secretion of viscous mucus, so it is possible that under these circumstances the aggressive use of beta agonists may contribute to

is defined as the production of watery sputum of 100 mL or more per day. This occurs in about 9% of patients with chronic asthma.

These are considered mucoregulatory medications and are most effective when bronchorrhea is associated with airway inflammation

Patients with congenital fucosidosis also have a form of bronchorrhea caused by the inability of mucins to polymerize. This form of bronchorrhea does not respond to

is a rare disease characterized by the formation of large gelatinous or rigid branching airway casts.59 These casts are more cohesive than those seen in ordinary mucus plugging. The casts can be spontaneously expectorated, and occasionally patients cough up large impressions of their tracheobronchial tree

The prevalence of plastic bronchitis is unknown. This disease may also overlap with diseases such as asthma and with the severe mucus plugging sometimes seen in bronchopulmonary

Patients who die usually have respiratory failure related to

is a chronic hereditary disease characterized by impaired function of the CFTR protein. There is chronic airway infection, often with Pseudomonas and other gram-negative organisms. There is also chronic airway inflammation, and infection and inflammation together lead to bronchiectasis, progressive pulmonary function decline, and eventually death.

The decreased mucin in CF sputum may be related to chronic bacterial infection by

Airway epithelia in CF show excessive absorption of sodium (Na+) compared with normal epithelia. There is a limited ability for the epithelial cells to secrete chloride (Cl-) through the chloride CFTR channels (see Figure 9-6) stimulated by cAMP. The result of excessive Na+ absorption and limited Cl- secretion may lead to

Physical properties of mucus include:

In the airway, adhesive forces refer to the attractive forces between

Mucokinetic agents are either abhesives, such as surfactant, which reduces the adhesivity of secretions, or agents that increase the power of

is the resistance of a fluid to flow. More specifically, is the proportionality constant (ratio) of applied force to rate of flow

is the ability of a deformed material to return to its original shape. Ideal solids store energy during deformation, and this energy is available when the force is removed

The viscous properties of an ideal or Newtonian liquid can be described by

The properties of an ideal or Hookean solid can be described by

The complex modulus (G*) is

is a viscoelastic material and responds to an applied stress as a fluid and as a solid

As the tips of the cilia contact the gel during the forward power stroke, the gel is stretched, and its elastic recovery causes it to snap forward. At the same time, the mucus gel flows forward as a liquid under the forward beat of the

If such a rubber strip is loaded on one end with a weight and allowed to hang, it would initially stretch as an elastic solid. If the applied force remains, the strip would slowly elongate because of its viscosity (i.e., the rubber would �flow�). After removing the weight, the rubber recovers most of the elastic elongation because of stored energy, but it would not recover the entire length because of flow. This describes?

The ability of mucus to be drawn out into threads was initially identified for cervical mucus; it was termed

Spinnability was found to increase with increasing

Spinnability and mucus transport were also found to decrease as the purulence of sputum from CB patients

gives information about internal cohesion forces in mucus

is defined as the product of cohesivity, and adhesive work. is one of the strongest determinants of the ability of sputum to be cleared by cough

The greater the tenacity of sputum, the worse the

Evaluation of mucus properties is complicated by the fact that mucus exhibits

Some mucus exhibits a sudden collapse of viscous behavior at high applied stress; this is called

Mucus is often thixotropic�stable at rest but becoming more fluid with applied

Because of its non-Newtonian behavior, evaluation of the properties of mucus and of the effect of drugs on those properties is complicated and must be performed under standardized conditions of dynamic shear rate and across the linear portion of

Three drugs are currently approved by aerosol to modify airway secretions

Mucolytic agents decrease the elasticity and viscosity of mucus because the gel structure is

The therapeutic options for controlling mucus hypersecretion are outlined as follows:

Classic mucolytics reduce mucins by severing disulfide bonds or

Acetylcysteine does not improve mucus clearance when given as an aerosol and should not be used as a

As a mucolytic, NAC has been used in conditions associated with

A second use of NAC is as an ________ to reduce hepatic injury with actetaminophen overdose

Because there are no data that show NAC to be effective for lung disease and because of the high risk of side effects, we do not