Final Cardiac Case Study

Cardiac Final Assignment

1. Mrs. Singh’s 12 Lead ECG is seen below.  Interpret this 12 Lead ECG using the systematic approach for ECG interpretation. Include the following:   i) Rhythm, ii) Axis, iii) Voltage, iv) Transition, v) BBB, vi) Hypertrophy, vii) MI location and viii) Stage of MI. (8 marks)

  i) Rhythm

The R-R intervals are regular.

 ii) Axis

Right axis deviation.

 iii) Voltage

250 volts.

iv) Transition

The electrical signals fibrillate.

 v) BBB

Present. The QRS complex is 0.24sec.

 vi) Hypertrophy

Right ventricular hyperthropy

vii) MI location

Ventricles

viii) Stage of MI.

ST elevation myocardial infarction (STEMI).

2. During initial assessment of Mrs. Singh you notice the following rhythm on the cardiac monitor. Interpret this rhythm and discuss nursing priorities (1 mark for interpretation; 2 marks for nursing priorities).

 Pulseless ventricular tachycardia.

Chest compression should be initiated immediately to ensure that adequate oxygenation to vital body organs due to the hearts inability to function normally.

Administer epinephrine after every three to 5 minutes while simultaneously looking for causes that resulted to the pulseless electrical activity.

Once a diagnosis has been the treatment is initiated immediately. In this case the cause is hypotension because the blood pressure is 98/60mmhg.  Intravenous Atropine 1mg should be administered every three to five minutes. The patient can be given up to three doses. Atropine is an anticholinergic agent that blocks the effects of acetylcholine by acting on the central nervous system.

Intubate and ventilate the patient with 100% oxygen.

3. What two priority interventions would be appropriate for Mrs. Singh post cardiac arrest. Note Mrs. Singh is intubated and ventilated. (Total 12 marks)?

Ensure that there is continuous of vital signs, cardiac and hemodynamic status.

Normalize the body temperature. 

Discuss the two interventions and include the following:

i. Rationale for the intervention (two marks each)

A 12 lead electrocardiogram and ultrasonography should be available on the bedside to assess the hearts electrical activity. This helps in the diagnosis of cardiac disorders such as cardiac ischemia, pericardial tamponade and structural heart abnormalities to allow for immediate interventions to be performed (Anderson et al., 2019). Vitals signs that are blood pressure, heart rate are assessed noting the rate, rhythm and presence to evaluate for the systemic, peripheral and altered cardiac output. 

Therapeutic hypothermia is the major cause of death post resuscitation. Isotonic intravenous fluids are used to hydrate the patient. These fluids are usually cold therefore it could cause a drop I the body temperature. The body should be actively rewarmed by using warm fluids and covering the patients although great care should be taken to avoid rapid rewarming that could lead to seizures, hyperkalemia and cerebral edema

ii. Nursing considerations for the interventions (four marks each)

The nurse should ensure that the equipment’s used in the 12 lead electrocardiogram are functioning appropriately to ensure that accuracy of the readings are maintained. The connections should be done correctly to avoid getting the wrong readings. Standard infection prevention measures should be adhered to because cardiac patients are susceptible due to their compromised immune status and use of invasive procedures to monitor the patient. 

Case Study (Phase 2) 

Two hours after admission, Mrs. Singh’s B/P drops to 78/50 and she has developed crackles in both lung bases. Her O2 saturation has also decreased to 88%. The intensivist/internist inserts a pulmonary artery catheter (PAC).

4. Interpret Mrs. Singh’s hemodynamic profile using the ‘grid approach’ (15 marks total) 

a. Analysis Mrs. Singh’s hemodynamic values (high, low or normal).      (1 mark)

Mrs. Singh’s Hemodynamic Profile 

HR 56; B/P 78/50; MAP 59;

PAP 39/22; Wedge 19; CVP 16;

SVR 2200; PVR 250; CO 3.8;

CI 2.1; LVSWI 30; RVSWI 6

 b. Examine preload, afterload, contractility and perfusion. Include the definition for each, and why each cardiac parameter would be high, low or normal in relations to Mrs. Singh’s clinical presentation and hemodynamic status. Consider how all parameters are inter-related.  (8 marks)

Preload is the amount of ventricular stretch at the end of a diastole (Tortora & Derrickson, 2018). Left ventricular preload is measured using the left atrial filling pressure or the pulmonary artery wedge pressure. Right ventricular preload is measured using right atrial pressure.

Afterload is the amount of pressure that the heart needs to exert to eject the blood during ventricular contraction(Tortora & Derrickson, 2018). Increased resistance during ventricular systolic ejection increases systemic vascular resistance (SVR) for the left ventricle and pulmonary vascular pressure (PVR) for the right ventricle.

Contractility is ability of the heart to eject a stroke volume (SV) at a given prevailing afterload (arterial pressure) and preload (end-diastolic volume; EDV)(Tortora & Derrickson, 2018).  Impaired contractility causes a decrease in the cardiac output.

Perfusion is the process whereby oxygen is transferred from the body tissues to the organs facilitated by the regular contraction and relaxation of heart whereby either deoxygenated or oxygenated blood is pumped in and out.

c. Briefly discuss potential causes. (2 marks)

Reduction in the blood pressure activates the baroreceptors in the carotid and sinus arch which causes nerve transmission to the central nervous system. This leads to decreased sympathetic impulses and hormones from the adrenal medulla that result in vasodilation which causes low blood pressure. The heart rate and stroke volume decreases leading to low cardiac output. Decrease in cardiac output causes low MAP.

d. Explore treatment (medications and interventions) appropriate for the Mrs. Singh’s clinical presentation, the above hemodynamic parameters and your determined causes. (4 marks)

Administer inotropic agents such as digoxin and dopamine (Anderson et al., 2019). Dopamine acts on beta 1 receptors located in the heart to increase the myocardial contractility and stroke volume which results in in a higher cardiac output.

Catecholamines are beta and alpha agonist receptors. Drugs that act on beta 1 receptors increase the force of attraction of cardiac muscles (Anderson et al., 2019). They increase the sympathetic nerve stimulation which causes an increase in heart rate, blood pressure and vasoconstriction of blood vessels. Examples of these drugs include epinephrine.

Case Study Phase 3

Later in the shift, Mrs. Singh’s cardiac rhythm has changed and a temporary venous pacemaker is inserted in an attempt to stabilize her cardiac rhythm (noted below) and her hemodynamic status. As the nurse, you identify some issues with this pacemaker.

5. First, interpret the following cardiac rhythm. As the nurse caring for this patient, what are the priorities for this rhythm? (1 mark for interpretation, 2 marks for nursing priorities).

Atrio ventricular block.

Monitor the vital signs and place the patient on a cardiac monitor.

6. Now, a transcutaneous pacemaker is applied and the mA (milliamperes) is increased to 60. Interpret the following strip. What priority nursing actions are required? (1 mark for interpretation, 2 marks for nursing priorities).

Ventricular ectopic beats.

Ask the patient about medications that can cause interference with the electrical activity. Lab investigations for urea and electrolytes should be carried out to establish potassium and sodium levels.

7. Your intervention is successful and Mrs. Singh is now in the following cardiac rhythm. Interpret this rhythm (1 mark).

Normal sinus rhythm.  

References

Andersen, L. W., Holmberg, M. J., Berg, K. M., Donnino, M. W., & Granfeldt, A. (2019). In-hospital cardiac arrest: a review. Jama, 321(12), 1200-1210.

Tortora, G. J., & Derrickson, B. H. (2018). Principles of anatomy and physiology. John Wiley & Sons.