PATHOPHYSIOLOGY AND PHARMACOLOGY

Running head: PATHOPHYSIOLOGY AND PHARMACOLOGY
PATHOPHYSIOLOGY AND PHARMACOLOGY
Name of the Student:
Name of the University:
Author Note:

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Pathophysiology and Pharmacology:
Asthma is an inflammatory disease condition that is associated with an inflammation
in the lower respiratory track. The inflammation mainly occurs in the smooth muscle walls
around the respiratory tubes and as a result, the airways become narrower and the individual
faces difficulty in breathing (Mims, 2015). Upon an encounter with antigens, the mast cells,
basophils and eosinophil cells are triggered. Those cells secrete various mediators that
prevent the smooth muscle cells from relaxing. As a result there is a pressure created on the
airways of an individual. There are two other layers also around the airways of an individual,
which are the epithelial cellular layer and the mucus. It has been observed in the asthma
patients that both of those layers are also thicker than the normal individual. Thus all three
layers creates an excessive pressure on the airways that delivers oxygen to the lungs and
carries the carbon di oxide out of the lungs. That is why an individual experiences difficulty
with breathing. The symptoms like breathlessness and wheezing are common in this disease
condition (Mims, 2015).
A bacterial infection in the upper respiratory tract also initiates an inflammatory
response in the respective area. The upper respiratory tract can also be described as the upper
airways. The nose, nasal passages, paranasal sinuses, pharynx and also some portion of the
larynx together can be described as the upper respiratory tract. The bacterial infection triggers
an increased mucosal secretion and thus there is a blockage results in the upper airways. The
symptom of frequent cough occurs in an attempt to clear the mucous constricting the airways.
The difficulty in breathing results additionally as the airways fail to provide a proper passage
for the oxygen to enter and the carbon di oxide to be excreted (Thomas & Bomar, 2019).
When an individual such as Benji have both the above mentioned conditions, the
severity of the symptoms increases. The individual experience the blockage in both upper and

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lower parts of their respiratory system at once. That is why they face an increased difficulty
with breathing and they cannot talk properly.
Primarily, Benji was prescribed with the salbutamol puffs as per his requirement to
keep his asthma condition in control. The salbutamol drug helps in the relaxation of the
smooth muscles, which creates pressure on the airways of the lower respiratory tract
(Billington, Penn & Hall, 2016). After he encountered a bacterial infection on his upper
respiratory tract, he was taking cough syrup. The case study does not mention, the exact name
of the drug. However, it can be assumed that he was taking an antitussive drug, which simply
reacts on the center at brain, from where the signal to cough is emitted. The drug does not
help to clear the airways of the respiratory system (Grewal & Huecker, 2019). Thus the
symptoms Benji was experiencing, did not get lowered and his asthma condition kept on
progressing.
Explanations of Three Symptoms:
The first sign that should have been addressed immediately in Benji was that the stage
of his asthma condition was progressing already, even before he encountered the bacterial
infection at his upper respiratory tract. He was wheezing and coughing as he attempted to
laugh. He was also avoiding sport activities as those activities were making his symptoms
more severe. The asthma condition in the children have also been known to be present in
three stages (Lizzo & Cortes, 2019). In the initial stage, a child does not display any
symptoms of asthma as he or she carries out their day to day activities. At the second stage
the child experience some of the symptoms during carrying out some specific activities such
as during sport. At the final stage, the child displays severe symptoms all the time (Lizzo &
Cortes, 2019). A child such as Benji required the immediate medical attention as his asthma
condition progressed to the second stage. That is why when he encountered an upper

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respiratory tract infection in addition to his mildly severe asthma condition, it became severe
within a short period of time.
The second sign was that even after taking four puffs of salbutamol and cough syrup
on a daily basis for the last week, his symptoms regarding the coughing and wheezing was
not improving. Due to a progression of the asthma condition in him, his lower respiratory
tract was experiencing a higher level of inflammatory response. This phenomenon not only
resulted in the swelling in the smooth muscle wall area around the lower respiratory airways,
it also increased the mucous production. The airways in the lower respiratory tract became
narrower and thus the free passage of oxygen and carbon di oxide into and out of the lungs
became interrupted (Lambrecht & Hammad, 2015). Any additional movement resulting from
laughing or sport activities were creating more pressure on the lungs, which were triggering
the symptoms like wheezing and coughing. Those symptoms are only the reflexive responses
of the body in order to clear the airways and provide a free passage for the lung’s activities.
Finally, when he was presented at the hospital, he was experiencing a considerable
difficulty with both breathing and talking. His respiratory rate and his pulse rate both were
higher than normal. The SpO2 level was lower than usual as well. The bacterial infection at
his upper respiratory tract, also initiated an inflammatory response involving the upper
airways of the respiratory system. As a result there was a blockage in the upper respiratory
airways as well along with the lower respiratory system. That is the reason for Benji
experiencing those severe symptoms of wheezing, difficulty in breathing and talking. His
lungs were working hard and thus his respiratory rate was higher than usual. All these
phenomenon resulted from the lower efficiency in the lungs’ activity lowered the oxygen
content in the blood (SIJU, 2016). That was the reason for the low SpO2 level in Benji.
Finally his heart was also working hard to deliver oxygenated blood all through the body.

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That is why his heart rate was also higher, which could be detected from his increased pulse
rate (Lutfi, 2015). Even after the presence of all these symptoms in Benji no immediate
actions were taken to stabilize him upon his admission in the hospital. Thus after thirty
minutes post admission his symptoms worsened. There were a higher pulse rate, higher
respiratory rest and a lower respiratory rate detected in Benji compared to the observations
that were taken thirty minutes ago.
Identification and Description of Three Medications:
The first drug that Benji was taking for his asthma condition, was salbutamol drug.
Salbutamol can be described as an adrenergic drug that acts by relaxing the smooth muscle
cells by a range of response (Hsu & Bajaj, 2019). The drug binds to a type of receptors
known as beta 2 adrenergic receptors, which are present in the smooth muscles of around the
respiratory airways. Upon binding of those drugs, the receptors are activated and as a result
the adenosine cyclase enzymes are also activated. Adenosine cyclase activation results into
an increased production of cyclic AMP (cAMP) molecules. The increased cAMP level
stimulates the activation of protein kinase A. As a result of that phenomenon the
phosphorylation in myosin gets inhibited and the intracellular Ca2+ concentration gets
lowered. A lower Ca2+ ion concentration in the muscle cells, stimulates the relaxation of the
muscles and thus the pressure on the airways are also lowered. The individuals with asthma
condition feel relief as their breathing gets easier (Hsu & Bajaj, 2019).
The drug has a half-life of around 2.7 to 5 hours. The drug is used as a bronchodilator
and the administration procedure involves both oral and parenteral methods. If the salbutamol
drug is taken as a mist, it takes about two to three hours before being available in the blood.
The volume of distribution of the drug is 156 +/- 38 L. The metabolism of the drug takes
place in the liver. Salbutamol is mainly excreted from the body via urine. About 58-78% of

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the initial dose of the drugs gets excreted from the body via urine. However, there is also a
small portion of the drug gets excreted via faeces (Welch, 2016).
The next drug that could be selected as the second most important treatment method
for Benji, was Ipratropium drug. This drug also helps in opening up the airways like
salbutamol. However, the use of a combination of both of these drugs is considered to be a
better intervention for the patients displaying severe exacerbations of asthma like Benji (Saab
& Aboeed, 2019). The ipratropium drug uses a different mechanism compared to the
salbutamol but assists the drug in relaxing the smooth muscle walls around the respiratory
airways and in opening up the airway. The ipratropium drug is an anticholinergic agent. It
acts as an antagonist to the muscarinic acetylcholine receptors. Acetylcholine is a
neurotransmitter, the level of which determines the diameter of airways. The acetylcholine
release is a signal for the smooth muscle contraction. Thus when an application of
ipratropium drug prevents the acetylcholine release the muscles remains relaxed. The
antagonistic behaviour of the drug on the muscarinic acetylcholine receptors also inhibits the
function of parasympathetic nervous system. The normal function of the parasympathetic
pathway is to initiate various bronchial secretions, which eventually leads to the smooth
muscle contraction. Thus by blocking this parasympathetic response, the ipratropium drug
also blocks the smooth muscle contraction. Thus when this drug is used as a combination
with the salbutamol drug, the smooth muscles around the respiratory walls remain opened
and the individual with severe asthma is able to breathe better (Saab & Aboeed, 2019).
The drug is mainly administer orally and it is intended for inhalation. The drug is not
easily absorbed by the human body. Only 1-2% of the initial dose gets absorbed and the
percentage also becomes available in the serum of an individual after about two hours. The
ipratropium drug has a very short half-life, which is about 1.6 hours. The volume of

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distribution for the drug is about 4.6 L/kg. The metabolism of the drug involves the activity
of cytochrome P-450 isoenzymes and the metabolism event takes place in the gastrointestinal
tract. About 90% of the initially administered dose of the medication gets excreted by the
urine in an unchanged from and the rest of the drug is excreted with the faeces. However, in
case of oral administration, the most of the excretion event occurs via faecal pathway (Quinn
et al., 2018).
The third most important medical intervention for Benji’s condition was the
administration of oxygen for his low SpO2 condition. A 95 to 100% SpO2 level in room air, is
considered to be a normal SpO2 level in an individual. A low level of oxygen in the blood
presents with the risk of low oxygen supply in the brain, which can lead to brain stroke if the
severity of the symptoms are not managed in a timely fashion. The oxygen gas administered
by either the use of the face masks or nasal tubes mainly (Pilcher & Beasley, 2015).
There was another medication that was prescribed for treating Benji, which was also
an important intervention to lower the severity of his symptoms. The medication
prednisolone is an anti-inflammatory agent, which is used for lowering the vasoconstrictive
effects in an individual. The prednisolone drug binds to the glucocorticoid receptors and as a
result to that event, various inflammation events are inhibited. There is a decreased leucocyte
migration along with a decreased vasodilation event and decreased permeability of the
capillaries. As a result of the decreased inflammation, the adverse effects of the wall of the
respiratory airways are also lowered (Puckett, Sharma & Kasi, 2019).
The drug is corticosteroid in nature and has a short half-life, which is about 2 to 3.5
hours. About 70% of the drug is available in the serum. The volume of distribution of the
drug is 29.3L for a dose of 0.15 mg/kg. The metabolism of the drug takes place in the liver.

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The 98% of the initial dose of the drug is excreted via urine (Schijvens, Heine, De Wildt &
Schreuder, 2019).

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References:
Billington, C. K., Penn, R. B., & Hall, I. P. (2016). β 2 Agonists. In Pharmacology and
Therapeutics of Asthma and COPD (pp. 23-40). Springer, Cham.
Grewal, N., & Huecker, M. R. (2019). Opioid. In StatPearls [Internet]. StatPearls Publishing.
Hsu, E., & Bajaj, T. (2019). Beta 2 Agonists. In StatPearls [Internet]. StatPearls Publishing.
Lambrecht, B. N., & Hammad, H. (2015). The immunology of asthma. Nature
immunology, 16(1), 45.
Lizzo, J. M., & Cortes, S. (2019). Pediatric Asthma. In StatPearls [Internet]. StatPearls
Publishing.
Lutfi, M. F. (2015). Patterns of heart rate variability and cardiac autonomic modulations in
controlled and uncontrolled asthmatic patients. BMC pulmonary medicine, 15(1), 119.
Mims, J. W. (2015, September). Asthma: definitions and pathophysiology. In International
forum of allergy & rhinology (Vol. 5, No. S1, pp. S2-S6).
Pilcher, J., & Beasley, R. (2015). Acute use of oxygen therapy. Australian prescriber, 38(3),
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Puckett, Y., Sharma, B., & Kasi, A. (2019). Cancer, Intraductal Papillary Mucinous Cancer
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studies. Pulmonary pharmacology & therapeutics, 48, 71-79.

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Saab, H., & Aboeed, A. (2019). Ipratropium. In StatPearls [Internet]. StatPearls Publishing.
Schijvens, A. M., ter Heine, R., De Wildt, S. N., & Schreuder, M. F. (2019). Pharmacology
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syndrome. Pediatric Nephrology, 34(3), 389-403.
SIJU, V. (2016). Childhood asthma.
Thomas, M., & Bomar, P. A. (2019). Upper respiratory tract infection. In StatPearls
[Internet]. StatPearls Publishing.
Welch, M. J. (2016). Pharmacokinetics, pharmacodynamics, and clinical efficacy of albuterol
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