MRCP Revision Notes Random Selection

Aortic Regurgitation

Patients with Marfan’s syndrome are at inceased risk of developing aortic regurgitation. Symptoms include dyspnoea on exertion, syncope, chest pain and congestive cardiac failure. On examination patients have displacement of the apex, prominent S3 sound over the apex, a low pitched apical diastolic rumble (Austin-Flint murmur) and an early systolic apical ejection murmur. CXR may reveal LVH and aortic dilatation. Ideally surgery should be considered before the ejection fraction falls to below 55%.

Complete Heart Block

A basal systolic murmur is consistent with the diagnosis. There is a slow, regular pulse that does not vary with exercise. Usually there is an increase in stroke volume with a large-volume pulse and systolic flow murmur. In an asymptomatic patient, a permanent pacemaker is indicated in second and third degree heart block at the distal conduction system. ‘Cannon waves’ in the JVP occur when the right atrium contracts against a closed tricuspid valve, these occur irregularly in complete heart block. CHB presents with bradycardia, relative hypotension and syncope. The patient needs to be referred for a permanent pacemaker. (Cannon waves are also seen in conjunction with VT)

African Tick Typhus

A man goes to Kruger National Park, saw animals being bitten by mosquitoes and tsetse flies. Returns to the UK and develops fever and a black spot on the thigh as well as a faint macular rash. The most likely diagnosis is African tick typhus. Malaria should be excluded. The organism is Rickettsia conorii. Treatment is with doxycycline which often leads to quick resolution.

Haemochromatosis:

Autosomal recessive disorder more commonly seen in middle aged men. Diabetes, hypogonadism, hepatomegaly and increased skin pigmentation are suggestive of the disorder. Serus iron and ferritin levels are raised. HFE gene, chromosome 6. High transferring saturation and a low total iron binding capacity.

Wallenberg Syndrome:

Left lateral medullary syndrome. Usually die to occlusion of the posterior inferior cerebellar artery or its parent, the vertebral artery. The syndrome leads to ipsilateral pain and numbness on the face, contralateral pain and temperature loss, nystagmus and an ipsilateral Horner syndrome. MRI imaging is the investigation of choice.

Henoch-Schonlein Purpura

A young man is seen in clinic with a rash over his buttocks and lower legs, pain and swelling in both knees. Two weeks previously he had an URTI. He has hypertension. Bloods show a raised IgA + raised ESR – urinalysis shows proteinuria. HSP is characterised by raised IgA levels causing IgA nephropathy. It is a small vessel vasculitis usually occurring in young adults and children.

Type II vs Type I Statistical Error

Type II error occurs when the null hypothesis is wrongly accepted ie. a false negative results – the risk of not detecting a significant difference when there is one. The Type I Error is most closely related to the p value. Standard deviation is the measure of the spread of a sample distribution.

Caffeinated Nation - The Damage Caused By Energy Drinks

This fantastic graphic relates to the problem of our over-use of caffeinated drinks and is provided by Allison Morris (onlinedegrees.org) and I think really highlights the issue well.

Please Include Attribution to OnlineDegrees.org With This Graphic

Post-Partum Hypertension

Working in obstetrics and gynaecology, a common job is to review women after delivery to ensure that they are fit for discharge from hospital to the community. It is not uncommon for patients to be found to be hypertensive following delivery. In the BMJ this week there is a clinical review article on post-partum hypertension which I'll aim to summarise here, mainly focusing on raised BP <6 p="" post-partum.="" weeks="">

The most common cause for hypertension after delivery is due to pregnancy induced hypertension or pre-eclampsia which occurred prior to delivery. Hypertension is common in pregnancy and affects 6-10% of pregnancies. There are certain anti-hypertensives which have been shown to be safe in women who are breast-feeding, including labetalol and enalapril. Women who continue to have raised BP and proteinuria 6 weeks after delivery need referral to a specialist for further investigation. It's important to remind women that if they have had PIH then they are at increased risk of high BP in future pregnancies, particularly if they have had pre-eclampsia. 

Pre-eclampsia, eclampsia or HELLP (haemolysis, elevated liver enzymes, low platelets) may present for the first time in the post-natal period. BP usually falls immediately after delivery but then steadily rises and peaks at day 3-6 post-partum as a physiological event. Transient hypertension may occur post-partum in normal pregnancies for reasons such as pain, fluid administration and change in vascular tone resulting in fluid shift into the intra-vascular space. Automated BP cuffs may underestimate BP and readings should be confirmed manually. New onset of pre-eclampsia would involve the patient complaining of symptoms such as headaches, epigastric pain, visual changes or possibly seizures.

Several studies have reported that BP should be expected to normalise within 3-7 days after delivery although this will clearly increase if there has been pre-existing hypertension. NICE recommend checking BP 6 hours after delivery and again at day 5 to identify women with late presentation of pre-eclampsia. Measurement of proteinuria immediately post-partum is not recommended due to the presence of lochia. Any patients who have been discharged to the community and are found to have BP >160/>110 will need re-referred to hospital for assessment and treatment. NICE have created guidelines and a useful flowchart for the safe management of out-patients with hypertension during the first 6 weeks post-partum. After discharge from hospital, BP must be checked at least every other day by the community midwife until targets are met. Data on anti-hypertensives used post-partum is extremely limited and mostly based on expert consensus but treatments should be chosen carefully to reduce risk of transmission to the baby during breastfeeding.

Improving Patient Nutrition and Hydration in Hospital

Patient nutrition and hydration are often overlooked by doctors when patients are admitted acutely to hospital. This has been an established problem for many years despite evidence about the clinical and financial costs of neglecting this area. In a recent study, one in three patients admitted to a care home or hospital were either malnourished or at risk. Patients who are admitted to hospital may be malnourished for many reasons, including poor appetite, swallowing difficulties and reduced cognitive ability. When a patient is admitted to hospital, adequate fluid and nutrition should be addressed. There are many reasons why malnutrition is important. It is associated with increased morbidity and mortality, and a two to three-fold increased risk of post-op complications. It may delay wound healing and puts the patient at increased risk of pressure ulcers and wound infections. Malnutrition also leads to impairment of the body's immune system and will prolong hospital stay by three days on average with a 50% increased readmission rate amongst this group of patients. Dehydration and 'over' hydration are common in the hospital setting but the subsequent morbidity and mortality is rarely recognised. Patients in hospital are on one hand at risk of developing acute kidney injury, whilst on the other hand at risk of acute pulmonary oedema.

NICE recommend that screening for malnutrition is carried out on all hospital in-patients on admission, usually this is carried out in the form of the 'MUST' charts. According to NICE, nutritional support should be considered in the following groups:

• BMI <18 .5="" li="">
• Unintentional weight loss >10% within past 3-6 months
• BMI <20 3-6="" 5="" and="" greater="" in="" li="" loss="" months="" past="" than="" the="" unintentional="" weight="">
• People who have eaten little or nothing for more than 5 days or are likely to eat little or nothing for the next 5 days or longer
• People with poor absorptive capacity, high nutrient losses, or increased nutritional needs from causes such as catabolism

Admission to hospital provides a vital opportunity for intervention, but what can be done? The first step is to identify patients at risk. To achieve this, there needs to be increased recognition and awareness from all staff (medical and nursing). Maximising normal food intake needs to be encouraged. If appetite is reduced, oral nutritional supplement drinks can be used in the short term. Refer the patient to the hospital dietician for assessment. If oral nutrition is inadequate or impossible, enteral tube feeding or IV nutrition need to be considered (although these procedures carry risk - ie. misplaced NG tubes).

With regards to IV fluids, this is often inadequate and from my experience tends to be quite hap-hazard in hospitals. One problem is the lack of routine and careful fluid balance assessment by senior clinicians and the reliance on the most junior doctors with the least experience to carry out this task. Decisions on IV fluids are often left to out of hours, when the doctor on-call doesn't know the patient or their fluid requirements and is asked to 'write up more fluids' without much thought due to time pressure.

Ways in which we can improve our practice in order to benefit our patients include implementing the current NICE guidelines and auditing compliance with them. Senior clinicians and managers also need to share responsibility in this area. A simple measure, such as a ward round checklist could be used to improve fluids and nutrition. Staff should encourage patients to eat and drink, with assistance provided to those who need it. 'Protected meal-times' and red-trays to identify those patients with increased need for help are good ideas. Improving patient education is also an important consideration. So in summary, nutrition and hydration in hospital patients is an important, often neglected area and now is the time to address the problems which I've highlighted. 

Reducing Risk of Stillbirth, Beta Blockers and the Public Enquiry into Stafford Hospital

Last week, following an inquest lasting almost a year, the results of the enquiry into
Stafford Hospital were released and the findings are very serious. The report found that
patients died needlessly due to poor care. The report makes 290 recommendations for 
improvements. In 2007, higher than expected death rates were reported at the hospital,
leading to investigation, and some of the findings were target driven managers, poor 
standards of nursing care, a culture of bullying, complaints being ignored and doctors
continuing to work under these poor conditions without speaking out. It should be noted 
that mortality rates are only one way of looking at how a hospital is performing. Rates
can vary for many other reasons with poor quality healthcare being only one. Nonetheless
the results from the enquiry deserve the high level of publicity which they have received
and should lead to important lessons being learned for other health boards. 

Working in obstetrics and gynaecology at the moment, naturally I've taken more interest
in related articles. There was an interesting one in the BMJ this week about identifying risk
factors for stillbirth. One of the common reasons for patients presenting to the maternity
outpatients department seems to be for ? reduced fetal movements. Fortunately most of the time a CTG 
(cardiotocograph) is reassuring, showing good fetal movements and fetal heart rate, meaning that the patient can be
safely discharged. Fetal stillbirth remains to be one of the few potentially avoidable maternal and child health
complications which hasn't declined in recent years. Patients who present to the out-patients are assessed for their
risk of stillbirth, but perhaps we should be doing more in the community to reduce the risk of stillbirth. Fetal growth
restriction, smoking and obesity are three important risk factors. Smoking in particular is easily modifiable (patients
must be encouraged to stop smoking), and fetal growth restriction should not go unrecognised. Despite this, a recent
population based study has found that in pregnancies ending in stillbirth, unrecognised fetal growth restriction was 
associated with 32% of all deaths. Identifying fetal growth restriction and smoking cessation are therefore important 
goals for antenatal care and could be the key to reducing the rates of stillbirths in Scotland.

Beta blockers have long been know to result in favourable outcomes in heart failure, and a recent study published in 
the BMJ this month has shown that beta blockers exert a class effect with no one particular drug showing favourable 
outcomes. The 'big three' beta blockers investigated were carvedilol, metoprolol and bisoprolol (these ones have the 
strongest evidence base). Recommendations are that unless there are obvious contra-indicationns (eg. asthma), 
stable patients with an ejection fraction of 40% or less should receive one of the drugs, but there is no one drug which
is preferable. Areas which require further study in the future include the global population variations in penetrance of 
beta blockers, and the use of beta blockers in patients with COPD as a co-morbidity (cardioselective vs. 
non-cardioselective agents).

Investigating the Link Between Sugar and Obesity

Is there a link between high sugar consumption and heart disease? Increased sugar intake has been linked to obesity but this link has remained a contentious debate over the past 40 years. Recently there has been a systematic review of the literature on the association between sugar consumption and body weight. The review found that an increase or decrease in sugar intake results in parallel changes in body weight over a period of time. A similar systematic review recently published looked at total body fat intake and led to similar conclusions.

Consumption of sugar leads to an increase in postprandial plasma glucose, increases insulin concentration and reduces the concentration of HDL cholesterol. It has been suggested that sugar increases body weight by overconsumption of energy, leading to recommendations that sugar intake should be limited. In 2003 the WHO recommended that sugar intake should be limited to 10% of energy intake.  Currently in the UK it is thought that this is approximately 15%.

Sugary drinks are thought to be a major culprit because they do not result in satiety in the same way which solid sugary food does, making overconsumption easier. Glucose and fructose are also perceived to be dangerous however their composition is almost identical to sucrose. Many strchy products with high levels of carbohydrates have metabolic effects comparable to sugar. The actions needed which have been put forward include not only reduction in sugar intake but also improving the quality of carbohydrates (reducing intake of refined grain and potato products).  Sugary drinks are probably the most significant and recent measures have been employed in an attempt to reduce the volume of sugary drinks sold (eg. the ban of ‘super-sized’ fizzy drinks in New York). In my experience patient diet is often not asked about routinely during medical admissions but we could be missing out on a valuable opportunity to offer significant lifestyle advice next time a patient presents with ischaemic heart disease or complications of diabetes.

Myaesthenia Gravis – A diagnosis easily missed?

A 78 year old man who has been previously well presents with a 6 month history of double vision and drooping of his eyelids towards the end of the day. On examination he has restricted eye movements and fatiguable ptosis. CT scan of the thorax is normal. EEG confirms the diagnosis of myasthenia gravis (MG) and he is commenced on treatment with pyridostigmine.

MG is an autoimmune disorder and it is characterised by fatiguable weakness. It is mediated by antibodies against postsynaptic acetylcholine receptors and approximately 10% of patients present with a thymoma. Symptoms may worsen in heat, times of stress, pregnancy and post-partum and it is typically proximal, with the upper limbs more affected than the lower limbs. Weakness becomes generalised in aproximarely 80% of patients. Bulbar weakness can manifest as difficulty in chewing or slurred speech. The most serious complication is a myaesthenic crisis where the patient develops respiratory failure and requires mechanical ventilation. Red flags for an impending crisis include worsening of symptoms, tachypnoea, tachycardia and respiratory infection.

Symptoms of MG can be fluctuating in the initial stages, leading to this diagnosis being easily missed. The incidence in older people in particular is thought to be greater than previously perceived but it is important to diagnose the condition because it is treatable. Management of the condition involves acetylcholinesterase inhibitors for short term symptomatic relief, and oral steroids (which may initially exacerbate symptoms). Second line immunosuppressive therapies such as methotrexate or rituximab may be used and IV immunoglobulin or plasma exchange are reserved for treatment of myaesthenic crisis. Thymectomy should always be performed if a thymoma is suspected.  Patients should be councelled not to abpruptly discontinue their medication and in those undergoing surgery a dose increase  may be required.  Aminoglycosides, quinine antibiotics and IV magnesium are contraindicated in patients with MG as these drugs may impair neuromuscular transmission.