Analysis of Acute STEMI Case Study: Pathogenesis, Strategy, and ABGs

This assignment analyzes a case study of a patient diagnosed with acute STEMI (ST-Elevation Myocardial Infarction). The analysis begins with an examination of the pathogenesis, detailing the occlusion of coronary arteries due to atherosclerosis, leading to chest pain and potential complications like ventricular free wall rupture. The document then explores a suitable nursing strategy, recommending reperfusion strategies like PCI or fibrinolytic therapy, emphasizing the importance of timely intervention. Furthermore, the assignment provides a critical analysis of the patient's Arterial Blood Gas (ABG) results, interpreting pH, PaO2, PaCO2, HCO3, and BE levels to assess the patient's acid-base balance, oxygenation status, and ventilatory control, highlighting potential hypoxemia and metabolic disorders. The analysis emphasizes the importance of prompt diagnosis and treatment to mitigate the risks associated with acute STEMI, referencing relevant medical literature to support the findings.

THE PURPOSE OF THE ASSESSMENT
IS TO ENABLE STUDENTS TO
DEMONSTRATE KNOWLEDGE BY
ACCURATELY ANALYSING
INFORMATION IN A CASE STUDY OF
COMPLEX CRITICAL CARE

Table of Contents
MAIN BODY...................................................................................................................................3
Pathogenesis related to acute STEMI..........................................................................................3
Nursing Strategy..........................................................................................................................4
Arterial Blood Gas results............................................................................................................5
REFERENCES................................................................................................................................1

MAIN BODY
Pathogenesis related to acute STEMI
The diagnosis of Mr. White shows that the chest pain that he suffered which reverberated
to his jaw and left arm was not simple indigestion but the development of acute STEMI where he
needs to be diagnosed with the treatment of such STEMI.
Acute anterior STEMI i.e. ST Elevation Myocardial Infraction occurs when the coronary
arteries that supply blood to the heart gets occluded. Atherosclerosis is that disease which is
majorly responsible for the development of Acute Coronary Syndrome Cases (Fitzgerald and
et.al., 2018). When the thrombus gets obstructed in a person due to some common causes such as
erosion, plaque rupture, fissuring or even dissection then this can lead to an abrupt disruption or
a barrier in the normal blood flow. A person can feel chest pain, discomfort or constriction in
breathing which might be taken outrightly as sings of fatigue or of indigestion.
A person who has family history of heart problems or more specifically coronary artery
diseases, has diabetes mellitus, taken hypertensions, indulged in smoking or has dyslipidemia
have a higher chances of developing Myocardial Infraction. When a person contracts acute
coronary syndrome than the chances of that person developing myocardial infraction is much
higher with an approximate figure of 42% people with acute coronary syndrome. When there is a
complete and regular occlusion of blood flow in a person, it leads to an elevated STEMI being
developed (Dai and et.al., 2017). It can be inferred that timely action is the key aspect in
avoiding damage to the Myocardial because immediate action can help in avoiding development
of serious problems as opposed to the delay in the action or taking the symptoms lightly.
An acute STEMI is a very risky and serious heart attack which can lead to the increased
exposure towards some life threatening diseases such as sudden cardiac arrest, ventricular
fibrillation etc. When a person develops chest pain which was acute in the case of Mr. White, it
can be stated that an immediate electrocardiogram i.e. ECG should be performed and the
troponin level should also be tested. After the diagnosis of acute STEMI in the patient,
intravenous access must be obtained and the cardiac monitoring needs to be started immediately
(Tadic and et.al., 2020). There is an increased risk of patients developing hypoxemia and
therefore, it is necessary that they should undergo Percutaneous coronary intervention (PCS)
within preferable 60 minutes or otherwise within 120 minutes as a maximum limit. If PCS can't

be given within the specified range, then the patient should be given fibrinolytic therapy i.e. it
should be initiated within the 30 minutes of arrival of the patient at hospital.
The ECG treatment or findings of the acute STEMI often shows an elevation in the ST
segment in the interior leads i.e. V3 and V4 at J point. Sometimes, it can also occur in septal or
lateral leads and depends entirely on the extent of Myocardial Infraction. When the elevation of
the ST segment is concavely downward then it quite frequently overwhelms what is called as T
wave. This description is often referred as tomb stoning because of the familiar shape to
tombstone. It can also cause, in the inferior leads, a Reciprocal ST Segment depression.
If a person develop myocardial infraction then there are chances that they can develop
three major life threatening complications which is ventricular free wall rupture, acute mitral
regurgitation or inter ventricular septum rupture (Fitzgerald and et.al., 2018). The chances of a
person developing ventricular free wall rupture is very high where 90% of the cases contract this
followed by rupture of the inter ventricular septum in 50% patient cases and the chances of acute
mitral regurgitation is even lower. Collectively, if treated immediately the mortality rate within
the patients can reduce.
Nursing Strategy
After the onset of STEMI, patients who have been treated with fibrinolytic therapy or
with PCI can be recommended with reperfusion strategy as the best nursing care strategy that can
be also be suggested for Mr. White in current scenario. Repurfusion strategy will help in quicker
recovery of the patient but then this will assist only if the criticality of time factor is kept in
mind. The door to balloon strategy i.e. D2B is the most effective strategy which should be used
within the 90 minutes and helps in opening up the blocked arteries by pumping in the air whereas
door to needle strategy should be executed within 30 minutes (Berry and et.al., 2017). Amongst
the reperfusion strategies that are available under STEMI, there are two major strategies that can
be adopted which are PCI i.e. Percutaneous Coronary Intervention and fibrinolysis. Both of these
strategies are effective in reducing the mortality rate but primary PCI is a much effective strategy
than other reperfusion strategies that are available.
However, if the nurse implement PCI, its implication is a complex procedure and if
Fibrinolysis is done, than despite its limited effectiveness, it is relatively easier to perform and
can be quickly administered as well. There is however a risk of blood loss in fibrinolysis. In

some cases CABGs can also be recommended but the most crucial thing is that the CODE
STEMI must be activated as quickly as possible.
The nursing strategy must be devised as quickly as possible and it should be implemented
quickly because time is the muscle in cases such as Acute STEMI and therefore this can assist in
restoring the health of the patient with minimum effects (Shuman And et.al., 2019).
Arterial Blood Gas results
The analysis of Arterial blood gas helps in the measurement of pressure of the oxygen and
carbon dioxide and the pH levels in an individual. This normally indicates the acid balance of the
patient, the state or effectiveness of the ventilatory control and the state of gas exchange. For Mr.
White the analysis can be made in following way:
pH: The pH indicates the presence of alkalaemia and since pH of Bill is within the range at 7.32,
it depicts stable pH level.
PaO2 and PaCO2: Since PaO2 is less than the normal level of 80 to 100 mmHg, i.e. it is 70, this
indicates that there are increased chances of hypoxemia in Mr. White. Since it can be further
analysed that the PaCO2 level in Mr. White is normal at 33 mmHg, this collectively shows that
the alveolar ventilation level is adequate in Mr. White and therefore the cause of hypoxaemia in
him is due to occlusion or the disturbance in the ventilation perfusion.
HCO3: This is referred as bicarbonate and is treated as a weak base where the metabolic
component in the arterial blood is measured (Harhash And et.al., 2019). This acts together with
carbon dioxide and therefore it can be interpreted that the range of is close to normal in Mr.
White. It can be stated that the respiratory system of the patient is at normal level i.e. the rate at
which blood is pumped to and fro form the heart is at normal level.
BE: Base excess is derived collectively from pH and PaCO2 and signifies the acid requirement in
order to restore the blood levels. In the patient, the BE is negative 3 and falls out of the normal
range of -2 to +2 mmol/L. It can be said that there is metabolite disorder in the patient but it
cannot be used to give any conclusive evidence.
Therefore, the interpretation of the ABG's shows that the patient shows the indications of
developing Acute STEMI yet the acid levels and metabolism of the patient is strong showing that
patient might contract ventricular free wall rupture but yet the mortality rate can be controlled
because of the quick control and admission in ECG within an hour allowing the treatment to
begin before the completion of the critical time of the patient.

REFERENCES
Books and journals
Berry, C. and et.al., 2017. Meta-Analysis of the Index of Microvascular Resistance in Acute
STEMI Using Incomplete Data. JACC: Cardiovascular Interventions. 10(4). pp.421-422.
Dai, M. and et.al., 2017. Recent prognosis of acute STEMI patients treated by primary PCI and
related factor analysis. Chinese Journal of cardiovascular Rehabilitation Medicine. 26(3).
pp.273-276.
Fitzgerald, G. and et.al., 2018. 42 Factors influencing total ischaemic time in stemi.
Harhash, A.A. And et.al., 2019. aVR ST segment elevation: acute STEMI or not? Incidence of
an acute coronary occlusion. The American journal of medicine.132(5). pp.622-630.
Shuman, M.E. And et.al., 2019. Short Term Follow up for Diabetic Patients Presented with
Acute STEMI Undergoing Preventive Versus Culprit Lesion in Primary Percutaneous
Coronary Intervention. Cardiology and Cardiovascular Research. 3(4). p.99.
Tadic, S. and et.al., 2020. P929 Routine Left Atrium Strain in acute STEMI: to do or not to
do. European Heart Journal-Cardiovascular Imaging, 21(Supplement_1), pp.jez319-562.
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