Friday 23 February 2007

Bread and Butter


Today's case is a time to consider reviewing common murmurs and how to identify a pleural effusion in a patient with heart failure.

This is a real case but I have as always anonymised the case. All pictures are self drawn so please excuse my poor artistic skills!

This elderly patient presented to another hospital with symptoms of fatigue, appetite loss and dyspnoea occurring over 4 days.

She was normally quite well and had just been on a recent trip within Japan. However, the patient began to feel weak and had difficulty walking far, needing to frequently rest. She also began to lose her appetite and prior to admission the patient was noticed to have difficulty breathing although the patient denied being breathless.

When seen, the patient admitted to being only able to walk no more than 100 metres before needing to rest. She rested normally for up to 2 minutes but had no chest pains. The patient had recently needed to prop herself up in bed with pillows to feel comfortable. Again, the patient denied being breathless!

The patient denied having a fever, cough, sputum, haemoptysis. There was no recent history of a common cold. Although the patient's spouse had said the patient had lost her appetite, the patient said there was no problem!

There was no history of any abdominal problem. No Genitourinary problems.

The patient was known to have Sick Sinus Syndrome for which the patient had a biventricular pacemaker, some mild dementia, and type 2 diabetes mellitus for which she took insulin.

Drugs included warfarin, digoxin 125mcg, donezapil and insulin.

There was a history of heavy alcohol use in the past but the patient had stopped drinking several years before and she still smoked 12 cigarettes per day.

When examined, the following findings were seen:

On inspection the patient looked relatively well.

BP 159/95, pulse 76 regular, Afebrile, Sats 97% on room air, Resp rate 30/min.

Hands showed some fine tremor and there were red palms. There was some early clubbing and no Quinke's Sign. There was no liver/ CO2 flap [asterixis]. Sclerae looked yellow. The tongue was blue tinged consistent with central cyanosis.

JVP was pulsatile and raised above 4cm. The Carotid was evident at the neck and pulsatile (Corrigan's Sign). Precordial examination revealed a left parasternal heave consistent with RV hypertrophy. Aortic area revealed a grade 2/6 systolic murmur with no diatolic component audible radiating to the carotids in the neck (aortic systolic murmur; probable aortic stenosis). The Apex revealed a 3/6 mitral pansystolic murmur radiating to the left axilla. Both murmurs increased in loudness on expiration.

Interestingly, there was a murmur in the tricuspid area (right side of the xiphoid process) and with slight radiation over the liver area consistent with tricuspid regurgitation. There was no pulsatility of liver as can be sometimes seen in TR (please see diagram 2).

Respiratory examination revealed 'stony' dullness at the left base. Vocal Resonance was reduced compared to the right side [ask patient to say 'hitotsu' whilst listening over the area of dullness and compare to the normal side; in effusion the sound decreases; in consolidation the sound increases] and the breath sounds were decreased over the area of dullness. These findings were consistent with a pleural effusion. There were also crackles on the surface of the effusion and at the right base (see diagram 3)

Abdominal examination was normal.

Lower limb examination revealed no oedema or evidence of deep vein thrombosis.

Clinical Impression:

1) Congestive Heart Failure

2) Mixed Valvular Disease (Mixed AS and AR, TR and MR)

3) Right Ventricular Hypertrophy

4) Left sided Pleural Effusion

5) Possible thyrotoxicosis / liver disease (tremor and red palms)

6) Possible recent MI (decompensated Heart Failure and possible silent event due to diabetes)

7) Possible alcholic cardiomyopathy (history of heavy alcohol use)

Chest Xray (diagram 1) revealed severe cardiomegally and upper lobe diversion (bat's wings or Butterfly shadow) and fluid in the horizontal fissure on the right. The left costophrenic angle was obscured [please don't refer to it as 'dull'; dull is a sound not the description of an X-ray shadow!! Pictures don't make sounds]

The ventricular pacing leads did not reach the apex suggesting that either the heart was normal size and surrounded by a large pericardial effusion, or the heart has enlarged significantly in the 15 years since the pacemaker was put into the patient.

ECG showed a single pacing spike and a wide QRS complex consistent with being paced.

Bloods showed a normal Neutrophil Count, Normal Haemoglobin, Slightly raised BUN but normal creatinine. Liver Function was normal. INR was 1.29 and therefore subtherapeutic. CK was 66 and troponin T was Negative. CRP was raised at 2.1 and monocytes were mildly raised making me suspicious of a possible viral aetiology for his decompensated cardiovascular status.

Blood gas revealed a respiratory alkalosis and hypoxaemia.

Hence, AMI had been ruled out here but not thyroid disease.

Echocardiogram revealed an ejection fraction of 29%, severely thinned LV wall, hypokinesis, 3rd degree TR and MR. There was 1st degree AR but no Aortic stenosis component. There was no pericardial effusion.

Sometimes the increased cardiac output associated with AR can cause a Flow Murmur that can be easily confused with AS as in this situation.

Hence the diagnosis here from history and physical was not altered significantly by other tests.

It was decided not to attempt removing the pleural effusion on the left as firstly it was relatively small, the patient had not had a long challenge with diuretic therapy, the patient was taking warfarin and the patient's heart was so large there was a risk of puncturing the ventricle.

The treatment suggested was 1) Furosemide 2) ACE inhibitor therapy

ACE-I therapy improves cardiac function by remodelling the myocardium and reduding hypertension, and it is also known to reduce hospital admissions. It is also protective of the patient's kidneys especially as she is diabetic. However, always be cautious with ACE-I / ARB / Aldactone therapy as it can worsen creatinine and cause hyperkalaemia. On starting an ACE-1 /ARB it is acceptable to see a rise in creatinine of up to 30%.

The funny thing was that I have NEVER done a CT scan for someone who presented with pure heart failure as history, examination and a simple chest Xray usually suffice. If an effusion is considered then an ultrasound is sought or even a diagnostic needle aspiration.

The CT showed all the features already found by other methods but two metallic objects were noted which were the pacing leads causing interference of the image on the CT scan!!

Thursday 22 February 2007

Lumbar Punctures-- Advice from B

If you already know how to do a perfect lumbar puncture (LP) procedure then great!! However, many first year doctors both here and in the UK have great difficulty in performing this procedure, in some cases because they have not had much experience and also tuition may not have been optimal.

The following is my way of performing an LP that should hopefully help junior doctors get it right in the end.

Firstly, does the patient actually need a lumbar puncture?? Is meningitis suspected or an SAH?? Does the patient have raised intracranial pressure. You should be checking for raised intracranial pressure in such circumstances by monitoring pulse and blood pressure looking for a Cushing's Reflex (low pulse, high blood pressure) and looking for papilloedema in the fundi and of course any NEW focal neurology.

If uncertain, then CT scanning should be performed to obtain images to try and rule out raised ICP.

If the patient does have raised ICP then you should not do an LP because by decompressing the pressure within the subarachnoid space from below with an LP needle can precipitate cerebellar-brainstem herniation and you then have a decerebrate patient!!

If you have a meninigitis case, then treating with antibiotics is the most important thing you can do, and if you want to get confirmation, then this can be done through obtaining blood cultures, throat and nasal swabs immediately, and PCR of CSF at a later date once signs of pressure have reduced.

So, if the patient does not have raised ICP it is safe to proceed with an LP unless the patient is on warfarin. An INR of less than 1.5 is usually safe for doing proecedures. If raised above this, and it is essential to do an LP, then the INR can be reduced by FFP in the acute setting.

I do not consider aspirin or other anti-platelet agents to be an absolute contra-indication as although they prolong the bleeding time, they do not affect the intrinsic and extrinsic coagulation pathways. More over the risk to benefit ratio tips towards doing the procedure in such scenarios.

When you have decided to do an LP please try and explain the procedure to the patient / family to obtain their permission -- this is called Informed Consent. It is necessary to explain that the procedure may feel uncomfortable although you should be using local anaesthetic in any case. You need to explain the side effects of the procedure including headache and the possibility of bleeding and introducing infection, although in my experience, this is rare. Also explain that the patient will need to usually lie flat for about 4 hours after the procedure.

Set up your tray with sterile drapes, iodine, 1% or 2% lidocaine (10ml), several LP needles, normal sized needles, a 10ml syringe, sterile gloves, a Manometer (for CSF pressure), three sterile tubes for CSF, a marker pen (not on the sterile tray), swabs and dressings.

1) Lie the patient in a Lateral position on either their Right or Left Side with their back parallel to the edge of the bed. Ask them to curl into a Foetus position-- hips and knees flexed with the knees as close to the abdominal wall as is possible. This will open the intervertebral spaces by flexing the spine.

2) Feel the top of the pelvis and then feel down to the lumbar spine. The vertical imaginary line will dissect the L4 vertebra-- this is the Intercristal Plane. Below this is the L4 intervertebral space and above is the L3 space.

3) Wherever is the most easiest place to enter use a marker pen to identify the site you wish to enter.

4) Now WASH YOUR HANDS and then put your sterile gloves on

5) Then put a sterile drape underneath the patient

6) Now, sterilise the skin with iodine in the area you want to put the needle into. Remember to also sterilise a wide field as you may have to go up higher if the space you have chosen does not work. Also, I sterilise the top of the hip and loin area so that I can find the Intercristal Plane and re-establish my land marks during the procedure. However, you may have drapes to allow just access to the designated area so you can re-establish your markings in any case.

7) You must use Local Anaesthetic during the procedure. Use 1% or 2% Lignocaine (lidocaine) and infiltrate the skin and deep muscle with a normal needle. Usually instill about 5 ml and wait until the patient cannot feel the prick of the needle on the skin. REMEMBER to ALWAYS draw back on the syringe before injecting local anaesthetic to look for blood or even CSF, because inappropriate entry into a vein or subarachnoid space can cause patients to have a seizure or cardiac dysrrhythmias.

8) Then, take your LP needle and angle the needle in the head direction and towards the umbilicus NOT perpendicular to the skin, otherwise you will hit bone. If you hit bone, then pull back and re-angle the needle upwards and advance again. If you keep hitting bone then STOP and try at a higher interspace, again have instilled local anaesthetic.

9) Once you advance the needle into the correct space, you will notice that it can go in quite deeply. You should feel some resistance to the needle and then a sudden loss of resistance that is called 'the Give'. You should now be in the subarachnoid space.

10) Now, withdraw the middle stylet of the needle and wait for the CSF. It may not come out immediately but with respiration the increased in CSF pressure should cause CSF drops to come.

11) You should now put on a MANOMETER to check the pressure in cm/mm of Water. A normal pressure is between 10-20cm of water.

12) Now take your samples of CSF, usually 10 drops, into three bottles. Label them up as 1,2 and 3 with number 1 being the first sample and number 3 being the final sample.

13) Normally 1 and 3 are sent for microscopic examination to compare white and red cell components. It is also examined for bacteria.

14) The 2nd bottle is sent for protein and glucose examination.

15) The stylet should then be reintroduced down the barrel of the LP needle and then the whole needle is removed. This is supposed to reduce post-LP headache by aiding sealing off of the dural hole created by the needle.

16) Press firmly over the entry site with a swab until any bleeding / swelling subsides and then apply a sterile dressing.

17) In my experience, the patient should lie flat for several hours although a recent JAMA 2006 article suggests that patients can ambulate soon after such a procedure. If the LP fails to produce CSF then a higher interspace level can be chosen such as the L3/L4 interspace or the L5/S1 space can also be chosen instead.

Sometimes it is necessary to do a Sitting LP. In this case the patient is sat on the edge of the bed and the doctor performs the LP from behind. The same interspace areas can be entered. This can sometimes be the only way to obtain the CSF.

Of course, if you have difficulty with a lying LP you MUST ask your Senior doctor to help you rather than repeatedly attempting the procedure.

I hope this helps and please let me know your experiences with LP procedures. I may not have covered every single problem with LP procedures here as it is a basic guide, and if you want to ask me a specific questions then please leave an anonymous entry on the blog and I will answer as soon as possible.

Monday 19 February 2007

Kwashiorkor--no way!!

The following case has been anonymised for patient confidentiality.

A few months ago a female patient was seen at a peripheral hospital in her 30s who was admitted with weight loss over several years. She denied all symptoms including loss of appetite, fevers, night sweats, cough, sputum, abdominal pain and diarrhoea.

However, on direct questioning she admitted to having some recent constipation, easy satiety with little food and leg swelling.

During her admission she was noted to have recurrent hypoglycaemia which occurred when she was taken off of the intravenous glucose infusion. During hypoglycaemia she developed dizziness and pre-syncopal symptoms but no sweating, shaking or hunger.

She was noted to have abnormal liver function but she denied drinking alcohol and had no history of risks for hepatitis B or C infection.

Her periods had stopped suddenly several years before, but before the weight loss, she admitted to only ever having 3 periods a year.

She had been investigated previously with a gastroscopy and colonoscopy to rule out malignancy and all had been normal.

Previous medical history was otherwise unremarkable.

When I reviewed this patient she was extremely low in body weight being only 30kg. She had diffuse muscle wasting and temporalis muscles were wasted.

She had cool hands and her nails showed Koilonychia (spoon nails) consistent with Iron Deficiency Anaemia. Her pulse was regular and approx 60 per minute. Her skin was thin and flakey and there were signs of multiple bruising all over her body. The knuckles of her hands showed callosities and her teeth showed some mild dissolution.

JVP was not raised. There was a normal thyroid on palpation and no evidence of lymph nodes.
Heart sounds were loud but no murmur was evident.

Chest examination revealed intercostal recession and percussion was difficult due to the patient's frailty. Chest sounds were normal with no signs of crackles or wheeze.

Abdominal examination showed a thin abdomen and on percussion the liver edge was below the costal margin by approximately two fingers. The liver was non-tender. There were no signs of chronic liver disease and bowel sounds were increased.

Legs were extremely oedematous and leaking. She had sores on her knees.

Clinical Impression

1) Anorexia nervosa (extremely emaciated, callosities on he hands, dissolving teeth, cool peripheries, oedema, secondary amenorrhoea, hypoglycaemia)

2) Likely multivitamin deficiency including signs of Scurvy (fragility of capillaries leading to multiple bruising)

3) Hypoproteinaemic state

4) Possible early liver cirrhosis due to malnutrition resulting in abnormal liver function and recurrent hypoglycaemia ( impaired gluconeogenesis, glycogenolysis and impaired glucogenesis)

5) Possible Iron Deficiency Anemia as a result of decreased nutritional intake.


Blood results revealed a low insulin and C-peptide level, borderline hypothyroidism, an albumin of 3.1, negative anti-insulin antibodies. Cortisol collection result was above normal with a high ACTH level. FSH and LH levels were decreased. GH level was normal.

Abdominal Echo showed some ascites but a normal pancreas. CT showed no evidence of malignancy. Cardiac echo revealed some mild pericardial effusion.

Suggestions

It was suggested that the insulin and C-peptide be repeated during an episode of hypoglycaemia and for a glucagon level to also be drawn. Moreover, I also suggested that urine sulphonylurea levels be checked to rule out self-administration.

The patient might have been developing cirrhosis due to severe malnutrition and hence, a liver biopsy would be an approprite next step.

In view of the severe low body weight and hypoglycaemia It was also suggested that the patient should have NG or PEG feeding as it might be the only way to ensure that the patient had sufficient and guaranteed calorie intake especially as the patient had shown signs of self-induced vomiting.

In view of the probable multi-vitamin deficiency, the patient would need replacement including ascorbic acid (Vitamin C).

This patient saw nothing wrong with being so under weight and often patients consider that they are over weight when they are fact severely under weight and hence, she might have an abnormal recognition of self-image. A psychiatric opinion would also be helpful although congnitive retraining can be difficult especially in older patients, and from the history of infrequent periods, I suspect that she has had an eating disorder most of her life.

Unfortunately, the secondary amenorrhoea, hypothyroidism and other features of this illness only abate when sufficient weight has been put on.

The patient clearly had anorexia nervosa and from the severe features of the disorder including hypoglycaemia, oedema, ascites and moderate liver dysfunction It was considered that she might have Kwashiorkor.

This disorder is seen in states of severe protein malnutrition and the features are the same as described in this patient. Anorexia nervosa is a recognised cause of Kwashiorkor.

With restoration of proper nutrition the features are reversible except those of liver disease if cirrhosis has developed.

This was an extremely interesting case for me and the history, physical and blood tests gave me the answer!

For thinking of causes of Hypoglycaemia, remember EXPLAIN.

EX- Exogenous e.g. alcohol, insulinl, sulphonylureas
P- Pituitary failure
L- Liver failure
A- Adrenal Failure
I- Immune e.g. insulin receptor antibodies
N- Neoplasia (rare e.g. insulinoma, haemangiopericytoma, retroperitoneal fibrosarcoma)

Always rule out drugs by taking urine screens, insulin levels with C-peptide.

For a more indepth explanation of hypoglycaemia and its investigation, please see a more detailed text.