Health Care - Pathogenesis in Relation to the Case study

Running head: HEALTH CARE
Health care
Name of the student:
Name of the University:
Author’s note

1HEALTH CARE
Pathogenesis in relation to the case study:
The case study is about Mr. Bill White, a 60 year old business executive who was
admitted to the emergency department following an episode of chest pain that radiated to the left
arm and jaws. He was given a diagnosis of ST-elevated Myocardial infarction (STEMI). STEMI
is a very serious form of heart attack which occurs when a major artery of the heart are blocked.
It is an even leading to myocardial injury or necrosis (Prasad & Raphael, 2019). According to
Foth & Mountfort (2019), the disruption of the blood flow occurs due to sudden rupture of an
atherosclerotic plaque with the coronary artery walls. The plaque contains cholesterol rich
material and contact of this material with the circulatory blood results in blood clothing. This
explains the mechanism behind the obstructed blood flow in the damaged artery. Thus, with the
increase in duration of blood occlusion, the blood flow and oxygen supply to the myocardium
decreases. Thus, due to reduced oxygen supply to the heart muscles, the cardiomyocytes send
signals to the brain which manifest as chest pain in patients (Boyette & Manna, 2019). Thus, Mr.
White also suffered radiating chest pain on his arm which was initially 6/10. Other clinical
manifestation of STEMI includes shortness of breath and diaphoresis. Mr. White experienced
shortness of breath too evidenced by respiratory rate of 28 breaths/min which is greater than the
normal value of 12-20 bpm. Shortness of breath occurs because of low oxygen demand and
initiation of compensatory mechanism in response to hypoxia (Prasad & Raphael, 2019). The
above process shows why Mr. White was tachycardic.
The analysis of laboratory test and other test results of Mr. White displayed other changes
that occurs during STEMI. His arterial blood gas results (ABG) was abnormal as all the five
elements in the ABG test (pH, PaO2, PaCo2, HCO3, BE and lactate was below normal limit. The
significance of ABG analyses is that it helps to monitor the acid-base balance and electrolyte

2HEALTH CARE
values of patient and identify any electrolyte disturbances that can cause complications in
patient. Mr. White’s lactate value was 2.0 mmol/L, which is much greater than normal range.
High lactate level is seen because impaired tissue perfusion and decreased oxygen delivery
during myocardial infarction induce heart muscles to initiate glycolysis and produce lactate from
pyruvate (Vermeulen et al., 2010; Gjesdal et al. 2018). Similar mechanism is seen in Mr. White
evidenced by lactate value of 2.0 mmol/L. The PaO2 value of patient was 70mmHg and this is
seen of progressive coronary occlusion during STEMI. As arterial blood flow is disrupted due to
occlusion, the gas-exchange process is hampered and oxygen deficiency decrease PaO2 level.
Low PaCo2 value occurs in the patient was 33 mmHg and it is an indication of hypocapnia in
response to beginning of hyperventilation following impaired gas exchange. The bicarbonate
value of Mr. White was 20 mmol/L and it is an indication of process to maintain acid-base
equilibrium manifested by neutralization of pH level (Hajar, 2016). For this reason, Mr. White’s
pH value was found to be 7.32.
The review of vital signs of Mr. White revealed RR value of 28 bpm, HR 120 bpm, BP
80/40 bpm and GCS value of 15/15. The blood pressure results of patient suggest that he is
hypotensive and this occurs due to severely impaired myocardial performance result in low
cardiac output, left ventricular systolic dysfunction and consequently hypotension. Patients often
become tachycardic because the heart attempts to increase cardiac output resulting in stimulation
of sympathetic nervous system and eventually and increase in heart rate (Li et al., 2017). In case
of Mr. White, electrolytes check was done. His troponin level was found to be significantly high
(88ng/L) and potassium value was lower than the normal limit (3.0 mmol/L). It is an important
biomarker of acute myocardial infarction and the value of this increase in patients with STEMI
in response to myocardial injury and cellular death (Prasad & Raphael, 2019). The potassium