Posted: May 9th, 2015

rationale development exercise

Rationale development exercise 1

In approximately 300 words critique information provided for reasons for the prescription of medications for Mr Diuresis and any possible side effects mentioned. Provide reasons (rationale) for all elements of your discussion.

Mr Diuresis, diagnosed with Heart Failure NYHA III, was prescribed oral frusemide 40 mg at 0800 and 1400hrs, Captopril BD, atenolol BD and Spironalactone mane.

Frusemide was prescribed to inhibit the reabsorption of K+ and therefore of H2O in the loop of Henle. Side effects can include hypovolaemia, hyperkalaemia and hypomagnaesia. Oral frusemide works within 30 minutes and the therapeutic effect lasts for 3 hours.

Captopril was prescribed to decrease the body’s compensatory RAAS mechanism which is maladaptive in HF. ACEI also results in vasodilatation. Side effects include risk for postural hypotension, dehydration and hypokalaemia. As captopril possesses a diuretic action the patient should be advised to increase dietary potassium. Captopril should be administered with food.

Atenolol prescribed to cause vasodilatation as it inhibits SNS system effect on β1 receptors and its sympatholytic activity reduces heart rate increasing the ejection fraction of the heart. Also prescribed to decreased cardiac remodelling.

Spironalactone is a specialised antagonist of aldosterone. It works in distal convoluted renal tubules and causes increased amounts of water and sodium to be reabsorbed and  potassium excreted.

Rationale development exercise 2

In approximately 300 words discuss what the clinical data in the case below indicates about the diagnosis and presenting condition of MrNaturesis. Provide reasons (rationale) for all elements of your discussion.

MrNaturesis, 63-years, presents to ED complaining of breathlessness for the past three days. Cardiac history is positive for a myocardial infarction three years ago followed by three-vessel coronary artery bypass surgery. Diagnosed with LVF 2 years ago.

Over the last three months MrNaturesis noted onset of shortness of breath while unloading groceries and walking up stairs. Two weeks ago, he was unable to complete his daily two-kilometre walk. He noted swelling in his feet and ankles. Four days ago he woke at 0200hrs short of breath and had to sleep in his recliner the rest of the night. He has been unable to lay flat in bed at night since then and has slept on 5 pillows.

T 36.8, P 140, irreg, R 30 and labored, BP 176/52, SaO2 90%, weight 78 kg (usual weight 75 kg). JVP increased; bilateral creps to mid zone. Cough is productive with frothy pink tinged sputum. Extremities: 4+ pitting edema of lower extremities to the knees.

Results of investigations: Na 120, K 2.3, Hb 98, HCT 33%. CXR: Cardiomegaly with diffuse pulmonary infiltrate. BNP 500 pg/mL.

Rationale development exercise 3

In approximately 300 words critique the care provided for the following patient. Provide reasons (rationale) for all elements of your discussion.

Mr Popliteal Femoralie was admitted to the cardiac ward following a failed radial angiogram and then a femoral angiogram with angioplasty and the placement of a stent in the left anterior descending artery. On return to the ward the patient is placed in semi-fowlers position to promote breathing, cardiac telemetry commenced as arrhythmias can occur post angiogram. Can ambulate after 2 hrs. Vital signs, examination of the site over the femoral vein for degree of softness and bleeding and neurovascular obs on both legs (for comparison purposes) are carried out every hour. IV fluids are continued at 100 mL/hr because the patient would have been fasting for the general anaesthetic and oral fluids not advised post general anaesthetic. Hourly observation of CWMS are also continued on the radial site and the TRB would be removed an hour after returning to the ward as there is a risk that this would decreases blood flow through the radial and the ulnar arteries. Once TRB is removed a compression bandage (e.g. Elastoplast) should be applied.

Example rationale development exercise

Mrs Russell is admitted with a suspected small bowel obstruction and paralytic ileus. Insertion of a large bore nasogastric tube, IVT at 125mL/hr and IV morphine infusion 0- 5 mg/hr was ordered. There has been no naso-gastric tube drainage for 2 hrs and Mrs Russell complains of nausea. She is ordered 3 IV anti-emetics namely Maxolon, Stemetil and tropisetron.

Administer a dose of Maxolon which will increase Gastric peristalsis allowing the gastric juices in the stomach to progress through the Lower GIT therefore decreasing nausea. It also has an effect on the vomiting centre in the brain so it the most appropriate and commonly administered anti-emetic in this situation.

Do not administer any of the antiemetics. The first action is to assess patency of the NGT and to assess for bowel sound as would expect at least >60mL drainage if a paralytic ileus was present therefore highly suspicion that NGT either blocked or not in the correct position.

Rationale

The administration of Maxolon is incorrect as it has a primary action of increasing peristalses and a secondary action on the vomiting center) and is according to most pharmacology texts contraindicated in SBO (Smith et al 2009; Toomey 2001; Harrison et al 2011). In a complete bowel obstruction gastric fluid (made up of at least 20mL of saliva and 30mL gastric juice per hour cannot pass into the bowel and builds up in the stomach. The NGT is required to rest the bowel and decompress the stomach. It is therefore essential prior to the administration of any antiemetic that the patency of the NGT and the activity of the bowel are first assessed (Crisp & Taylor 2012). If the NGT was patent bowel sounds absent and the patient was still nauseated assess for other causes of this nausea. If the cause was related to the effect of a narcotic then either Stemetil or Tropisetron are considered more appropriate in this case (Harrison et al 2011) as they have a primary effect on the vomiting centre.

Recommended References to use in this three rationales :

Porth, C 2011, Essentials of pathophysiology, 3rd edn, Lippincott, Williams & Wilkins, Philadelphia, USA, pp. 377-512.