Cardiology


Cardiology


Mark A Rodrigues and Emily R McCall-Smith


Outline





Initial Assessment








Initial Investigations



ent Bloods: FBC, U&Es, ESR, CRP. Look for evidence of inflammation. Troponin is used as a marker of myocardial damage (elevated in ≈50% with pericarditis) but may also help differentiate from acute coronary syndrome. U&Es will show elevated urea in uraemic pericarditis


ent ECG: Classical finding is widespread ‘saddle-shaped’ ST elevation with upwards concavity in I, II, aVF, aVL and V3–6. PR depression is virtually diagnostic of pericarditis. Helps distinguish from myocardial infarction


ent CXR: Can range from normal to the classic water-bottle-shaped heart seen with pericardial effusions. Helps exclude differential diagnoses such as pneumothorax and pneumonia


ent Echo: Will show pericardial effusions (present in 10% of cases of pericarditis) and tamponade if present–though tamponade should be diagnosed clinically. It will also demonstrate concomitant heart disease, such as left ventricular wall motion abnormalities seen post-myocardial infarction



‘Bloods show an elevated WCC (18×109/L), ESR (48 mm/h) and CRP (63 mg/L). Troponin and U&Es are normal. ECG shows widespread concave ST elevation and PR depression. CXR shows mild cardiomegaly, with clear lungs and no pneumothorax. The ECHO shows a small pericardial effusion.’



Initial Management [1]



ent This patient has acute pericarditis, most likely secondary to a viral infection


ent Airway support: Airway patent in this case, with no intervention required


ent Supplementary oxygen: If saturations<94%


ent NSAID: Ibuprofen is preferred due to its side-effect profile and large dose range (300–800 mg 6–8 hourly depending on severity)


ent Colchicine: Can be used in combination with NSAIDs or as a monotherapy as a second line treatment. Dose is 0.5 mg oral twice daily


ent Additional analgesia: Use the World Health Organization pain ladder, starting at the most appropriate level


ent Gastric protection: Should be considered in all patients starting NSAIDs particularly those at increased risk of gastrotoxicity such as the elderly


ent Thromboembolic risk assessment: This should be considered but, in a potential pericardial effusion, avoid blood thinning agents due to risk of haemorrhagic transformation of the effusion.




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Figure 2.1



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Figure 2.2



Corticosteroids are not routinely used in acute pericarditis. They are reserved for patients with connective tissue disease, autoimmune or uraemic pericariditis. Corticosteroids may also be helpful in recurrent pericarditis, and in patients refractory to NSAIDs and colchicine. image








Initial Assessment






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Figure 2.3



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Figure 2.4



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Figure 2.5





Initial Investigations



ent CXR: Look for the typical features of LVF, although the radiographic changes can lag behind the clinical picture. Features of pulmonary oedema on chest X-ray are bat’s wing shadowing, pleural effusions, Kerley-B lines, cardiomegaly and upper lobe diversion. Look for other causes of acute dyspnoea, such as consolidation or pneumothorax


ent ECG: Look for ischaemic changes indicating an MI which may have caused the LVF, or arrhythmias, such as fast AF, which can cause or be a consequence of LVF


ent ABG: This will likely show hypoxia. Initially the PaCO2 might be low due to hyperventilation, but may rise later due to reduced gas exchange. Look to see if the patient is acidotic, as this is important in determining whether CPAP (type 1 respiratory failure) or BiPAP (type 2 respiratory failure) is required. Remember patients with renal failure may already have a metabolic acidosis, and therefore could be acidotic with a normal PaCO2 as well as with type 2 respiratory failure. Indeed a metabolic and respiratory acidosis might exist together


ent Echo: An important investigation to be performed early. This may demonstrate the cause of heart failure, e.g. left ventricular systolic dysfunction or aortic stenosis, which guides decision about treatment later on, e.g. ACE inhibitor/beta-blocker for LVSD, surgery for AS


ent Bloods: FBC, U&Es, LFTs, TFTs, CRP. Look for evidence of infection by doing an FBC and CRP. Look for anaemia as this may exacerbate heart failure. Check U&Es as you will be treating the patient with diuretics and an ACE inhibitor, and look at the LFTs–which may be deranged if there is hepatic congestion in right heart failure. Check blood glucose for diabetes. Troponin may be high if an MI has precipitated the LVF; however, it may be difficult to interpret as it can be raised by LVF itself. Thyroid function tests should be done, as thyroid disease can aggravate or mimic heart failure



‘CXR shows cardiomegaly, upper lobe venous diversion, pleural effusions, with fluid in the horizontal fissure, and Kerley-B lines. ECG shows sinus tachycardia. Bloods show a normal FBC, urea 6.8 mmol/L, creatinine 156 µmol/L, eGFR 58 mL/min, Na 140 mmol/L, K 4.2 mmol/L. TFTs are in progress. LFTs are normal. ABG on air shows type 1 respiratory failure, with a PaO28 kPa, PaCO24.9 kPa, pH 7.35, HCO324 mmol/L.’



Initial Management [2]


The acronym ‘L, M, N, O, P’ is a helpful way to remember the most important treatments:



ent Loop diuretic: Treat with furosemide. If the patient is diuretic naïve and has normal renal function, then 40 mg IV is adequate. If the patient is already on diuretics or has renal failure, then higher doses may be needed, e.g. 50–100 mg IV. Doses above 50mg must be given by IV infusion, and at a rate no faster than 4 mg/min. Elderly people, especially if they have a low body weight, will also require a dose reduction. Diuretics will cause immediate vasodilation as well as the delayed diuresis


ent Morphine Sulfate: Titrate 1–10 mg in 1 mg increments according to response. It will reduce anxiety and pain, as well as causing vasodilation which will reduce preload on the heart. Reduce the dose if the patient is elderly, frail or has a history of respiratory disease. Don’t forget to prescribe a prophylactic antiemetic with it, for example, metoclopramide 10 mg IV. Monitor respiratory rate while giving morphine


ent Nitrates: Give 800 micrograms (2 sprays) of sublingual glyceryl trinitrate immediately providing the systolic BP is>100 mmHg. Common side effects are headache and hypotension. For patients with severe LVF, or patients who haven’t responded to SL glyceryl trinatrate+morphine, consider a nitrate infusion (if BP still>100 mmHg). The starting dose depends on baseline BP, usual dose is 0.3 mg/h–1 mg/h. This will reduce the cardiac preload


ent Oxygen: Should be given to treat hypoxaemia when oxygen saturation is<90%, which is associated with an increased short-term mortality. Oxygen shouldn’t be given routinely, as it can cause vasoconstriction and reduced cardiac output. Consider CPAP for early refractory hypoxia


ent Posture: Simple but important–sit the patient up


ent Monitor urine output: Insert a catheter. This will demonstrate whether a good diuresis has occurred. Start a fluid balance chart


ent If the patient has evidence of bronchospasm, treat with salbutamol nebulizer, e.g. 5 mg, which will improve work of breathing and improve oxygen saturation


ent DVT prophylaxis: As per local protocol, to be given in patients not already on anticoagulation with no risk factors


ent Consider early HDU/ITU referral: The patient may need CVP monitoring, or ventilation support (CPAP for type 1 respiratory failure, or BiPAP for type 2 respiratory failure).




Reassessment



‘Mrs Jenkins does not appear to be much better. She is still producing secretions and is now requiring airway support with an NP tube. RR is now 36/min. Oxygen saturations are 93% on 15 L oxygen. There are still loud bibasal crackles. HR is 125 bpm and BP is 98/66 mmHg. Peripheries are clammy with a CRT of 3 seconds. Cardiac examination is unchanged. Mrs Jenkins has passed approximately 10 mL of urine over the last 45 minutes. The nurse is worried about managing her on the ward as they have other patients who require their attention.’


You need to speak with ITU urgently. The patient has had a poor response to the initial treatment. In severe or resistant cases, patients may require support with an intra-aortic balloon pump. Invasive monitoring and inotropes may be required, particularly as she is now hypotensive. Obviously this is something that a junior doctor will not be required to deal with, but it is useful to know what further treatment may be available.



When you’re working night shifts you will often be given a pile of fluid charts for patients who are on IV fluids. While it can be time consuming to assess every individual patient, this scenario highlights the importance of regular fluid reviews. image




Handing over the Patient to ITU


‘My name is Emma Smith and I’m the FY1 covering the wards tonight. I’d like to discuss a patient with you, whom I’d like you to review please.


The patient is Mrs Jenkins, an 84-year-old lady, who has developed acute pulmonary oedema this evening, after treatment with IV fluids for the last 2 days. She is known to have a history of moderate LVSD, but has no other significant medical history.


She has failed to improve significantly despite high-flow oxygen, morphine, furosemide and glyceryl trinitrate spray. Her current observations are oxygen sats 93% on 15 L oxygen, RR is 36/min, HR 125 bpm, BP 98/66 mmHg. She has a markedly elevated JVP, coarse bibasal crackles and bilateral pitting oedema. She has only passed 10 mL of urine in the last 45 minutes.


She was previously independent and had a good quality of life, and we feel that she would be a candidate for escalation of her care. I’m just about to repeat her ABG, but please could you review her urgently.’



When referring a patient to ITU you should be able to give a bit of background about their co-morbidities and pre-morbid functioning. Was Mrs Jenkins living independently prior to admission or was she in a nursing home? Did she get out to socialize or do her shopping or was she housebound with a package of care? Does she have any other chronic illnesses for example chronic respiratory disease or end-stage cancer? These are all important factors in considering whether a patient is an appropriate candidate for intensive care treatment. image



Definitive Management


‘After 24 hours in ITU, Mrs Jenkins has improved, and she is transferred to the ward for ongoing care.’



ent Closely monitor the patient’s symptoms, signs and observations


ent Measure the fluid intake and output on daily fluid balance charts


ent Tailor ongoing treatment according to clinical response


ent Weigh the patient daily


ent Monitor U&Es daily. Diuretics, for example, can impair renal function and cause hypokalaemia, ACE inhibitors can impair renal function and cause hyperkalaemia


ent Medications used after the acute phase:


ent Diuretics–to relieve symptoms of fluid overload, tailor the dose to the patient’s clinical need


ent ACE inhibitors–(or ARB if ACE inhibitor not tolerated) recommended in all patients with an ejection fraction≤40%. This reduces the risk of future heart failure-related hospitalizations and premature death. Start at a low dose and titrate up, monitoring U&Es after each increment


ent Beta-blockers–once the episode of acute left ventricular failure has been stabilized. They are recommended for all patients with an ejection fraction≤40% to reduce the risk of future heart failure-related hospitalizations and premature death. Titrate dose up, monitoring HR and BP after each increment


ent Mineralocorticoid (aldosterone) receptor antagonists, e.g. spironolactone or eplerenone–recommended for patients in class II–IV heart failure and an ejection fraction of≤35% despite the above treatment, as it again, reduces the risk of future heart failure-related hospitalizations and premature death


ent Digoxin–used in patients with reduced ejection fraction and coexisting AF. Can also be used in patients with severe and resistant LVSD to reduce symptoms and reduce heart failure-related hospitalization


ent Aspirin–for patients with atherosclerotic disease


ent Look for a cause of heart failure: this may involve an angiogram, measuring blood pressure, or further blood tests looking for a potential cardiomyopathy, e.g. TFTs, Ferritin, B12


ent Patient education is important–diagnosis and treatment should be discussed, as well as risk factor modification, diet, and general lifestyle advice


ent Consider involving a specialist heart failure nurse for ongoing patient education and review in the community.



Nov 18, 2017 | Posted by in PHARMACY | Comments Off on Cardiology

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