Friday, 4 May 2007

Abuse Of My Blog

Dear Readers

I am occassionally getting anonymous comments that are an abuse of this blog and as moderator, I must choose whether such comments should be published.

In the main, most polite and reasonable comments are published.

I should stipulate that only clinically related comments in respect of this site will be published and not advertisements for peoples books!!

However, I feel it is now necessary to restrict all comments by asking all those who wish to leave a comment to do so by signing into Gmail.

I trust that you will understand reasons for this decision as I hope it will ensure that the quality of legitimate comments is maintained.

Wednesday, 2 May 2007

WOW!!! What A Case For Differential Diagnosis !!!!

I have another GREAT CASE here which comes from a distant hospital.

The case is anonymised as always.

The patient was an elderly female who was referred to the hospital after an emergency call out for Chest Pain.

The patient had awoken at 10:30pm when she got up to visit the toilet. She developed sudden onset of chest pain that was severe and continuous and sharp in nature. The pain was also described as radiating to the patient's back. After 1.5 hours the patient arrived at the hospital and quickly underwent emergency examination.

Further history was taken and it became apparent that the pain was situated to the left of the epigastrium (so called the left hypochondrium). It was unrelated to movement or respiration. The patient denied being breathless, and it was apparent that this was the first time this pain had occurred. There was no associated cough, sputum, haemoptysis, radiation to the neck/jaw/arms, no nausea, no vomiting, no report of recent tarry stools (malaena). There was no history of GERD and no history of flatulence. The patient denied weight loss, constipation or diarrhoea. There was no description that the radiating pain was tearing or not.

The only previous medical history was of hypertension which the patient had for 10 years. She had decided to stop her anti-hypertensive medications 3 months previously without medical advice.

The patient smoked 60 cigarettes per day and liked to drink sake.

On examination, the patient was afebrile, BP 200/120, heart rate of 68/min, respiration rate was 16/min with an Sp2 of 96% on room air.

Physical examination was unrevealing except for signs of liver disease (palmar erythema and spider naevae on the upper chest).

Chest and abdomen revealed no localising signs for the cause of the pain and the abdomen was not distended and apparently non-tender.

However, the ECG revealed ST depression and T wave inversion in V5 and V6 suggestive of ischaemia.

Blood results revealed a normal initial CPK 86 (61-265) but the CK-MB was raised 17 (4-16) but Troponin T was <0.05.>3.3, AST 75 (13-37), gamma GT 467 (12-49), CRP 1.13 (<0.30) style="font-weight: bold;">pH 7.485, pCO2 38.5, PO2 64.9 (74-108), HCO3 29 (21-29), BE 6.2.

The top differential diagnoses included:
  • Acute MI
  • Pulmonary embolism
  • Unstable Angina
  • Aortic Dissection
The chest roentogen looked normal.

The CT abdomen was revealing as it showed a very abnormal aorta. See below:

On seeing the patient by a senior doctor, it became apparent that the history was slightly different. In fact, the patient had described ABDOMINAL PAIN, rather than chest pain as relayed by the paramedics to the hospital staff, and it was described as 'PULSATILE', not sharp, meaning for every heart beat the pain recurred i.e. pulses of pain. It was also asked whether the patient had been experiencing back pains in the SAME LOCATION sometime before the severe pain to which the answer was YES.

The patient denied symptoms of intermittent claudication (ASO).

The patient had undergone emergency surgery and the diagnosis was described as a pre-rupture of an Abdominal Aortic Aneurysm (AAA). The surgeon described it as pre-rupture as there was no bleeding into the retroperitoneal space. The location was infrarenal and involved the iliac arteries as well. The patient had a graft placed and achieved good haemostasis and pulses to both limbs.

However, it was also of concern about the aorta higher up in the patient's chest as on initial inspection of the Contrast CT, it looked like there was a proximal dissection that had migrated to the lower abdominal aorta. On more detailed inspection it appeared that there were two separate vascular luminal dissections, one in the thorax and one in the abdomen, the latter being the bigger of the two.

It was of concern that the more proximal dissection had been overlooked in the emergency situation because of the large possible impending rupture of the large abdominal aortic aneurysm.

Hence, it was requested that the doctors have the radiological films formally reviewed by a Radiologist and the result is below:

Thoracic lesion: dissecting aortic aneurysm (thrombus closing type) is seen from the bifurcation of the left subclavian artery to the upper surface of the diaphragm .
Lower abdominal dissecting aortic aneurysm (New pathologic lesion) is seen. At least TWO dissected cavities are overlapped. They are not enhanced, but the density is comparatively high.

Upper abdominal lesion, there is no dissected area but some enlarged lesion can be seen.

Radiology confirmed a total of THREE dissecting aneurysms in this patient.

This is an extremely interesting case, and it is rare to see three dissections in a single patient.

Obviously, the surgeons were concerned about impending aortic rupture as a result of continuing oozing of blood into the aortic wall, and hence, the patient underwent emergency surgery, but in the main, uncomplicated distal dissecting aortic aneurysms are treated conservatively with blood pressure control.

The more proximal dissections involving the aortic root and arch DO require surgical intervention on an emergency basis as complications such as stroke, aortic insufficiency, coronary ischaemia, tamponade and haemothorax (left sided) can occur, all of which may be fatal.

However, by far the commonest cause of dissections is vascular injury by high blood pressure and in the main, hypertension is associated with distal dissections rather than proximal ones, as in this case.

Other causes include:

  • Trauma/iatrogenic- cardiological investigations / procedures e.g. coronary angiography, CABG, Previous aortic valve replacement
  • Inflammatory disease causing vasculitis e.g. syphilitic aortitis, Takayasu's arteritis, RA etc
  • Collagen Disease: Marfan's Syndrome (approx 50% cases of dissection aged <40 style="font-weight: bold;">Ehlers-Danlos syndrome, annuloaortic ectasia
  • Congenital: Biscupid aortic valve- dissection always involves the ascending aorta, Coarctation of the Aorta, Turner's Syndrome (associated with coarctation)
  • Drugs: Cocaine; transient rise in blood pressure from surge in catecholamines
Finally, to recap, most dissections occur in the 60-80 age group and more in males than females.

The pain of dissection is SEVERE and can be Sharp or classically 'tearing' in nature in the rear of the chest or produce back pain. Pain can also be in the anterior chest. The pain can radiate to the chest or abdomen.

Proximal dissections are more associated with chest pain and distal dissections with abdominal and back pain respectively as a general rule.

Examination should include examining all the peripheral pulses. Typically, if dissection is present one may see a 20mmHg difference in blood pressure in the upper limbs.

Examine the JVP, as may be elevated in Tamponade.

Examine for Pulsus Paradoxus-- drop of >10mmHg BP during inspiration; associated with Tamponade.

Listen for reduced heart sounds and listen for the diastolic murmur of Aortic Regurgitation (proximal dissection).

Percuss the chest for effusion (might be a haemothorax)-- however, patients typically will have internally exsanguinated if this is present.

Listen for bruits or absence of bowel sounds-- suggestive of vascular compromise.

Check neurological examination if evidence of weakness as it implies vascular occlusion by the migrating dissection (proximal dissections).

ECG can be normal, especially in Distal dissections, but in proximal type, it may cause coronary ischaemia.

Chest Xray can be normal in dissection and does not exclude the diagnosis.

Once dissection has been considered, it must be excluded, and scanning modalities such as CT are quick and provide a degree of accuracy to reach the diagnosis.

Finally, well done to the doctors who got the diagnosis and treated the patient quickly !!!

Have a Great Golden Week!!!!!!!!!

Tuesday, 1 May 2007

UpToDate Keeping Me UpToDate

Dear Readers

It would seem that although I am reading UpToDate for some of the best EMB and references around, UpToDate USA and Japan are reading this blog too!!

I recently had contact from their Japanese Office Director, and I very much welcome the review of this blogsite as they will only find complimentary words for such a great product.

I have been kindly advised that the UpToDate software should work on Japanese Windows Pocket PCs, for example, the Willcom PPC made by Sharp.

If any of you have UTD which has been having any problems on your Japanese PPC then please contact the UTD Japan Office and I would hope that they will be able to sort them out as soon as possible :)

UpToDate, Inc. Japan Office
Sumitomo Shinbashi Bldg.7F
1-8-3 Shinbashi Minato-ku
Tokyo 105-0004
Tel 81-3-3572-5002
Fax 81-3-3572-5003

Best wishes.............