Friday, 25 January 2008

TropT or Not To Be- That is the Question

Dear Bloggers

This case clearly demonstrates that one should always take the Troponin T level seriously even in the presence of renal failure.

The case is from an international hospital outside of Japan and it has been anonymised for patient confidentiality.

A female patient was admitted into another hospital with appetite loss.

She was a known heavy drinker and smoker with a history of poorly treated diabetes mellitus and hypertension.

She had become abruptly unwell one week before with appetite loss and apparently little other symptoms. She had refused to take food or water and four days prior to admission had stopped taking her medications.

She denied nausea, vomiting, jaundice, abdominal pain, constipation, diarrhoea, weight loss, cardiac and respiratory symptoms.

She was taking Acarbose and Perindopril and she had no drug allergies of note.

Family and social history were unknown.

Physical examination by the resident was apparently unremarkable including the vital signs.

However, chest Xray revealed evidence of an enlarged heart and signs of heart failure as evidenced by upper lobe diversion of blood.

Laboratory data revealed evidence of renal failure with a BUN 100 and creatinine of 3.2. Na & K were normal.
Liver function was abnormal consistent with an alcoholic hepaitis picture.
Blood sugar was 350.
Serum and urine ketones were negative.

CK was 1000, CK-MB was normal. Troponin T was 2.1

ABG revealed a compensated metabolic acidosis. Bicarbonate was 18 and BE -4. Lactate level had not been measured.

ECG revealed ST elevation on a background of a wide QRS complex

Senior doctors reviewed the patient and it was considered that the patient might have developed an acute coronary syndrome plus or minus diabetic ketoacidosis aside from the alcoholic hepatitis.

However, a junior resident had discussed the case with a cardiologist from another hospital by telephone, and had therefore not been able to see the patient, who considered the raised Troponin-T to be as a result of the renal impairment in the absence of an echocardiographic report.

The patient was re-examined and a pan-systolic murmur was heard near the apex of the heart with loss of splitting during respiration.

Nevertheless, it was still considered highly likely that an Acute Coronary Syndrome had occurred, as it had not been ruled out, and an echocardiogram was performed.

The echo clearly showed diffuse hypertrophy of the myocardium but with an infero-apical area of hypokinesis and rupture of the interventricular septum to a size of 5-6mm.

The renal ultrasound scan ruled out obstruction and showed the kidneys to be of normal size suggesting that the insult on the kidneys was acute rather than chronic.


1) Silent AMI due to severe, chronic diabetes mellitus
2) Rupture of myocardium due to 1 above
3) Pre-renal +/- intrinsic renal dysfunction
4) Metabolic acidosis due to AMI (lactic acidosis), renal failure, hepatic damage

Moral Of The Story

MI can present in atypical ways. In this case, the patient lost her appetite ! The diabetes contributed to the 'Silent' nature of the cardiac event. Despite renal failure being present and there being a raised Troponin-T, it does not rule out the presence of a new AMI. Certainly there have been many studies showing that renal failure increases the Troponin level correlated to the degree of renal impairment, but such patients are in fact, high risk for myocardial events in any case. Hence, a Troponin-T in renal failure has to be taken seriously and not overlooked as merely trivial.

Moreover, the idea of DKA is good because AMI can precipitate DKA in a diabetic although that is typically in Type 1 patients rather than type 2 patients, which the patient was not in this case.

The criteria for DKA are as follows:
pH < 7.3
HCO3 <15
BE > -10
Blood sugar > 200mg/dl (>11.1mmol/L)
Ketones +/++/+++ on the urine dipstick

This patient had none of the above except for the raised glucose and hence, DKA seems actually less likely in this patient.

However, renal failure with a myocardial infarction and hepatic damage seem more likely the causes of the metabolic acidosis and the fact that there was respiratory compensation goes somewhat against DKA. Most DKA patients are severely ill with Kussmaul respiration at presentation and they rarely attain a respiratory compensation. Moreover, the time scale is not compatible with DKA. This patient had a one week history of illness whereas most DKA patients (particularly type 1 patients) present within hours !

So, in summary, do not overlook the Troponin T in patients with renal failure especially when there are additional ECG changes consistent with Acute Coronary Syndrome. The raised CK and abnormal ECG were new problems, and every problem must have an assessment and a plan. You must exclude cardiac causes first. Do not let the opinions of other deter you from doing a thorough investigation of causes when the index of suspicion still remains high.

Have a great weekend !!!

Thursday, 24 January 2008

Should Medicine Become Protocol Driven??

Dear Bloggers

What are medical protocols and should we be using them?

Medical protocols are a step wise guide to treating a vast array of conditions based on current evidence and moreover, on the provision of local services. We have all seen medical textbooks with 'their way' of doing things, and then pick up a different textbook to find that it is done slightly differently in that. With so many doctors using so many different opinions, it is sometimes difficult to know which one to choose. Do we base our final decision on how many grey hairs the senior doctors has or do we base it on evidence derived from trials and case-reports??

In a medical world of constantly changing medical information, it is sometimes difficult to remain up-to-date. It is important to remain appraised of new information because patients benefit directly from it. However, if we are all doing things a little bit differently, we should consider adopting a single way of 'best practise' so that there is standardisation throughout departments and throughout hospitals to ensure a basic and sustained uniformity of basic treatment.

Such methodologies do exist. Many UK hospitals have protocols for DVT, PE, Cellulitis, AMI, Stroke, Community Acquired Pneumonia etc... which are rigorously followed to be compliant with the modern evidence based practises. Hence, nevertheless who is on duty and nevertheless to the time of day or night, the basic standard of best practise can be applied.

I for one, having worked night duties, it was sometimes difficult to remain thinking clearly, quickly and precisely at 3 o'clock in the morning, and hence, following protocols for common medical conditions ensured that the work-up and treatment were followed appropriately and accurately. This can be especially useful for junior doctors who may not be accustomed to all the medical processes for safe patient care.

These types of protocols are especially good for the management of antibiotic use in the hospital inpatients and in the outpatient clinic. A protocol based on local resistance rates, severity of illness, and of course, cost to benefit, are used in many hospitals to guide the physicians on what they may be allowed to prescribe. Hence, most hospitals will not allow drugs such as the carbapenems to be utilised unless specified by a Consultant. More traditional antibiotics are used in combinations to provide effective broad spectrum cover and this cuts down on the abuse of antibiotics plus gives definite rules to the doctors on prescribing. In a World of ever expensive treatments, being cost effective is now very important. Protocols can help with this process.

Some may say that they do not want their autonomy taken away from them and they should have the ability to make changes and do things the way that they see fit. Indeed, for a seasoned senior doctor, the use of a protocol may not be necessary because they may have the knowledge to know what treatments should be administered and why. This is not the case for junior doctors who are simply trying to survive the long nights of sleeplessness and barrage of the daytime problems. The use of a protocol to guide them exactly how it should be done is both helpful and safe.

If a problem was to occur, then the junior doctor would also have the legal protection that they had followed the pre-specified hospital protocol.

Of course, not all things in medicine can be fastened down to a rigid protocol as there needs to be leeway and flexibility. However, for common medical problems as I have laid out above, the use of hospital adopted protocols that are available on every ward or outpatient in paper or electronic format can ensure that any doctor can appropriately investigate and administer the correct treatments at any time of day or night.

I for one have trained in a system that began to adopt the protocols for medicine several years ago and I found it extremely helpful.

Please consider... :-)

Monday, 21 January 2008

An example of Good Practise

Dear Bloggers

Having travelled to Hokkaido recently, I was able to see an example of good practise at the hospital to which I went.

The medical team who is headed by Dr Kaneko, run a Ward Round based system whereby all medical patients are reviewed daily by the senior physicians along with other staff doctors, junior residents, nursing staff and ancillary staff such as the speech & language therapist. This multi-disciplinary approach is excellent, as it is possible for all members of the team to understand the current clinical problems and of course, the social problems of patients to thereby be able to comprehend the full picture of the patient's current state.

This is an excellent example for learning at the bedside and making decisions based on history, physical and review of laboratory and radiological tests.

The fact that the patients are seen daily by senior doctors is a safe-guard for the patients in case errors are made by less experienced physicians or difficult-to-make decisions are required.

This is a very similar system to that of most UK hospitals whereby all medical patients are seen daily and where the Consultant will see the patients several times per week.

However, some hospitals in Japan do not have such a Ward Round based system whereby junior residents have to muddle through due to a lack of senior support. Moreover, medical meetings are held away from the bedside so that only history and physical, derived from perhaps an inexperienced junior resident, is heard, and decisions are then based on that plus the usual laboratory and radiological tests. There is of course no way to know if the resident has interpreted the history or physical findings correctly which thereby allows potential inaccuracies to become propagated through the inpatient stay unless the errors are identified early by a senior physician.

Such a no-hands-on approach can lead to errors which an experienced eye may pick up and soon avert.

In view that history taking and physical examination are not emphasized heavily in most Japanese medical schools, how can one expect junior residents to realistically pick up all the problems effectively?

Unless the emphasis of medical student training can be changed to reflect the changing needs of medicine, then the emphasis needs to be focused heavily on junior resident training.

Hence, a hands-on review by the senior doctors is essential to prevent mistakes being carried through into an admission and to teach the junior doctors appropriately to prevent the same problems occurring again in the future. A ward based approach is extremely important for the patient and for the resident training, rather than looking at numbers and pictures in a closed room. Some things cannot always be explained and it therefore requires a visit to the bedside to understand the problems.

Such senior doctor-led ward rounds of all the medical patients, a so-called 'business round' in the UK, is great for passing on 'gems' of information to the junior doctors with respect to history, physical, natural history of the disease and treatment plus how to understand the management of multiple clinical problems. Unfortunately, most books of clinical medicine deal only with distinct diseases rather than diseases in combination which a great number of patients have. That is the downfall of clinical books. However, the best teacher for this type of medicine comes from the Ward Round based teaching and discussion of evidence and experience of previous patient examples.

I, as a junior doctor, found it very helpful to also see the approach of the Consultants and how they dealt with difficult situations, such as telling bad news. To see how the different approaches worked allowed me to learn a great deal and to emulate the good examples. To see how the patients were treated with dignity and respect was also a good learning experience.

We do not start our lives as doctors and we are all human beings at the end of the day. Just because we become a doctor with a license does not mean we have all the necessary knowledge to manage patients at the start; far from it. We all need good role models to learn those things which are in no book, cannot be written down and can only be gained by approaching with a senior doctor to the bedside of the patient and seeing together. This is the basis of a medical vocation.

I think the experience in Hokkaido reminded me that there are many different ways to practise Medicine in Japan in addition to other good ways to learn medicine too.

Keep up the good job!

Have a great day....!