Examination of Witnesses (Questions 40-56)|
9 DECEMBER 2004
Q40 John Austin: On the question of clinicians'
preferences, Mr Warwick was saying earlier that some surgeons
may like to rely on aspirin and my understanding was that although
there are certain prophylactic benefits from aspirin it is not
particularly preventative in terms of DVT.
Mr Warwick: For orthopaedic thromboprophylaxis
it is second rate without a doubt. It is just not adequate. That
view is supported by, for example, the American College of Chest
Physicians which has looked at it all and it does not work well
enough. You may say it only costs two pence a tablet and that
is that; we are cheap on tariff and that is what we are going
Dr Keeling: I would like to raise
an issue about cost because, as was said earlier, thromboprophylaxis
is cost effective. This, if implemented properly, will save money;
it will not cost money. However, you then have a problem where
an individual is not allowed to prescribe the drug because he
is spending his money but saving money somewhere else. This is
a common thing in the Health Service which is a real problem.
A simple example: there is a blood test called a D-dimer when
you investigate these people for DVT which costs £2.50. My
department does hundreds of them and our budget has gone up; people
have got very cross about that. However, doing that test saves
a lot of money because you do not have to do different investigations;
you do not have to do tests in the radiology department. It costs
my department money but the radiology department is saving money.
No-one can look at the bigger picture; no-one can get round the
bureaucracy of people telling me off for doing D-dimer tests or
telling him off for trying to prescribe thromboprophylaxis. The
message should be clear: it may cost money to actually write the
drug prescription but overall proper implementation would save
money; it maybe somebody else's money, but it will save money.
Professor Kakkar: If one goes
back to this research in the United States that shows that implementation
of an appropriate protocol is the number one safety practice available
to hospitals, then I think it becomes a hospital-wide issue rather
than an individual patient group issue. I think that part of the
debate has to be to allow these important hospital-wide practices
to be implemented in trusts without the need maybe to provide
it by individual tariffs.
Q41 Mrs Calton: Can I just pick up on
consent? It seems to me from a certain amount of personal experience
but also listening to yourselves, when consent is done well and
it seems to go through all of the details and give the patients
the pros and the cons, and it is not just a matter of looking
at a form that has had thromboembolism written on it which the
patient may well feel they have put that on to cover themselves
legally but actually it is not going to happen to me. I am just
concerned that the consent form is not necessarily the best point
at which the patient can be educated and be fully informed about
the risks. Can you give me some idea yourselves as to whether
this is the right time? The consent form is widely viewed by patients,
I would have thought, as being the medical profession covering
itself rather than actually a point where they are going to give
the patient any real assistance.
Professor Kakkar: My own personal
view in terms of consent in general is that it is probably the
most important thing we do because patients undergoing surgical
intervention must understand the benefit and risk of what we are
going to do for them. You have to judge the individual risks of
what patients are going to be offered and I think a lot of us
now do our consent through a variety of procedures in the pre-admission
clinic and provide patients with an opportunity to discuss it
a few weeks before their operation and come back with any questions.
I think that is the best form of consent, to see patients in pre-admission,
discuss with them both the benefits of their procedure, the risks
of the complications of that procedure. I think thrombosis for
many procedures should be discussed as a risk. They should be
given a second opportunity when they are admitted to hospital
to discuss that again and as part of that providing written literature
for patients is important. One of the things trusts may do is
to provide simplified written information with regard to the thrombosis
problem for the individual procedures that patients may be experiencing
which would help them decide the benefits versus the risks of
Mrs de Cossart: Can I come back
to you on the comment about surgeons particularly protecting themselves.
I think that is an interesting and perceptive comment which is
worthy of some investigation because I think we have been made
to feel that we do it for that very reason. That actually is the
worse reason to do it. I think the consent form is a sham and
is a myth with respect to protecting the whole system about good
medical practice. Good medical practice requires the clinician
talking to the patient to develop a good relationship with them
and talk appropriately about what is going to happen to them.
Nothing and no paperwork can take awayI do not believe,
but correct me if I am wrong in your experiencethat rapport
and understanding that can be created between clinician and patient.
I think the paperwork we have introduced as a short-term measure
to cover these issues is clouding the need for clinicians to get
up to speed with it. If I may make an example of that, I have
already alluded to the fact that the lower, less experienced doctors
are being almost excluded or the understanding is prevalent now.
I had a conversation with a SHO who said that pre-registration
house officers cannot take consent; they are not allowed. My comment
was that that is not true; the actual requirement is that when
they take consent they have been taught to do it and they understand
how they do it, but the mindset that is coming through by this
paperwork is creating a different attitude to the process. The
educational mountain in front of us is huge. I think the consent
form can be very good or extremely bad and in a lot of cases it
is probably not worth the paper it is written on.
Q42 Mrs Calton: Particularly given this
condition where it seems to appear very often after the patient
has left hospital and so if the patient has not had a full discussion
presumably they have no idea about what might happen and what
the symptoms might be.
Mrs de Cossart: That is right.
Q43 Dr Naysmith: Should the paperwork
not be filled in by the physician? It should be a means of eliciting
the discussion that you think should happen.
Mrs de Cossart: Absolutely and
I think done well it does go very well but I think the issue is
that sometimes people do not pay attention to detail and there
is still a problem for people filling in that first part of the
consent form to a standard which most of us would aspire to.
Q44 Mrs Calton: Could I just a little
bit more about the increased incidents of bleeding? I think Professor
Kakkar mentioned that it was 1 to 2% or something like that and
clearly will be of more consequence in some patient groups than
in others. We have had the guidelines that exist described as
excellent. Do the guidelines actually go into all the different
patient groups and the information that is available there?
Professor Kakkar: They do, yes.
The American College of Chest Physicians' latest version published
in September of this year has a chapter on prevention of thrombosis
which has reviewed about 800 articles on prophylaxis, its efficacy
and the risks of bleeding. It breaks down its recommendations
by individual groups: general surgical patients, orthopaedic surgical
patients, medical patients, vascular patients, neurosurgical patients
and so on. In the discussion where they reach their final recommendations
for each of those patient groups they review both pharmacological
methods of prophylaxis, mechanical methods of prophylaxis, the
evidence or the efficacy of those individual methods of prophylaxis,
the bleeding risks associated with those, the balance for the
individual patient group and then they reach a recommendation
which is graded on the basis of the quality of the published literature.
That grading is determined by the methodology that has been used
for the individual clinical trials so: was there an appropriate
end point? Was there independent blinded adjudication of the results
for efficacy and blinded adjudication of the results with regard
to bleeding? Was the study appropriately statistically sample
size adopted? I think there is information for individual groups,
but there are some groups of hospitalised patients where the data
still does not exist to the extent that it does for other groups.
Dr Keeling: I would like bleeding
to be kept into perspective. Let me give you a very short quote
from the ACCP guidelines when it is talking about why prophylaxis
is not widely used. It says, "Abundant data from meta-analysis
and placebo controlled blinded randomised clinical trials have
demonstrated little or no increase in the rates of clinically
important bleeding with a low dose heparin or low molecular weight
heparin". That is the statement and I think the problem is
that if someone is using prophylaxis and the patient bleeds, they
will automatically say, "Oh this patient is bleeding because
they are on heparin, I wish I hadn't used it" but in fact
they may well have bled anyway. We go right back to the beginning
when Mr Warwick said that they see that but what they do not see
a reduction if fatal pulmonary embolism from 0.7% to 0.2% on a
day to day basis.
Mr Warwick: Orthopaedic surgeons
believe it is an issue and there is a substantial body of UK orthopaedic
surgeons who do value the problem of bleeding more than the value
the problem of thrombosis and I think a lot of that is due to
a perception bias, in fact they attribute bleeding to a drug if
you can because it is easier than blaming yourself. It is also
an issue of how much they understand the literature; they may
not have realised that the literature has been assimilated, for
example, in the American College of Chest Physicians work. I think
that any sort of guideline that is imposed on surgeons without
taking account of that fear would be so fiercely resisted it would
not be taken on board, hence our local guidelines, for example
in Southampton where we have a mechanical bias earlier on but
very much recognise the strengths of chemicals in the longer term.
I think that has to be recognised to be appreciated and taken
Q45 Mrs Calton: Can we go on to infection
risk. Is there any evidence of an association between thromboprophylaxis
and increased post-operative infection rates?
Professor Kakkar: I think in general
surgical patients one or two very large trials have looked at
whether prophylaxis or different methods of prophylaxis actually
have an impact on the overall outcome of surgery in terms of bleeding
and potentially wound dehiscence or wound infection and so on.
As far as I am aware it is not clear to me that there has been
any evidence of a substantial increase in infection associated
with pharmacological prophylaxis.
Mrs de Cossart: I would agree
with that. There is no evidence of it but we all know from clinical
experience that if you get a haematoma in a wound then your risks
of getting it secondarily infected are higher than if you do not
get a haematoma. If you do have a wound haematoma which is known
to occur and is the most common complication of subcutaneous heparin
therapy then you do increase the potential. Whether that potential
is a real risk is another matter.
Q46 Mrs Calton: We now hear that venous
thrombosis is commonor at least some of us now hearin
patients with cancer. What special considerations need to be made
for the care of patients suffering from cancer to prevent venous
thromboembolism and does having venous thromboembolism when already
suffering from cancer adversely affect outcome? Why are we not
prophylaxing everybody with cancer?
Professor Kakkar: That is my own
particular area of research interest. It is a difficult area for
patients undergoing surgical intervention for their cancerslaparotomies
for abdominal or pelvic cancerand it very clear that post-operative
thrombosis is an important problem. All the guidelines do in fact
indicate that for abdominal and pelvic cancer surgery that prophylaxis
should be provided at least for the duration of hospital stay.
For hospitalised non-surgical cancer patientsthose who
come in because of complications of their chemotherapy or because
they have an infection or they are dehydratedthey are then
confined to a hospital bed and immobile and those too should receive
thromboprophylaxis. I think the big problem is in advocating routine
thromboprophylaxis to the large numbers of cancer patients who
are treated outside hospital with chemotherapy or radiotherapy
where there are only very few trials at the moment in limited
numbers of cancer patients and only really investigated in breast
cancer patients. It is difficult to make recommendations about
routine thromboprophylaxis for that large group of ambulant patients
but there are a large number of trials looking at those patient
groups at the moment. The problem is, of course, once a cancer
patient develops a thrombosis they are at a much greater riskthree
times greater riskthan a non-cancer patient of getting
a recurrent thrombosis and they are twice as likely to get significant
bleeding complications while receiving treatment for their thrombosis
than a non-cancer patient. It has a devastating impact on their
quality of life. There are some very early suggestions which I
think need to be taken with caution to suggest that developing
a thrombosis in cancer has an important potential impact on the
outcome of that cancer. That is a very complex molecular question
at the moment about how the activated blood clotting system changes
the behaviour of the tumour and that again is an area of active
Q47 Dr Taylor: The crucial thing to me
is implementation. We have talked a little bit about it; we have
gathered there are a lot guidelines, there are a lot of protocols
and they are not being implemented. Dr Hunt, how have the obstetricians
implemented the guidelines which you obviously imply they have?
Dr Hunt: They have worked very
clearly on a set of data. They have an internal confidential inquiry.
There is quite a strong cohort of research people in venous thrombosis
in the obstetric community in this country, particularly in Scotland;
we probably lead the field. They have been very influential in
the Royal College of Obstetricians in highlighting the problem
and the Royal College of Obstetricians have numerous guidelines
for the different types of thromboprophylaxis we can apply and
also for the treatment of venous thromboembolism. If you go to
an obstetric meeting quite often there is a discussion about the
management of venous thromboprophylaxis or venous thromboembolism.
It is high up in their agenda; they are very, very aware of it.
I think because of the maternal inquiries they have a very strong
Chairman: That is a very important point
you are making. We were discussing privately about the fact that
here we have some definite evidence whereas in other areas the
information is much vaguer. This is a very key element of the
evidence, I think.
Q48 Dr Taylor: I was going to ask how
we can translate this from the College of Obstetricians to the
Dr Hunt: There is evidence it
is occurring but in obstetrics there are not actually very good
trials looking at the efficacy of thromboprophylaxis but everyone
is doing it because they think it is a good thing, whereas if
you look at the medical and surgical areas there are superb trials
that show that thromboprophylaxis works. There are six in medical
thromboprophylaxis which are of outstanding quality, and it is
not happening. It is a bit of a paradox really.
Mrs de Cossart: We have to remember
that every group of patients is different. The obstetric patients
are young women with a lot of children involved and carries a
huge emotional and important impact with respect to the group
of people who may die from pulmonary embolism. Of course, until
recently pulmonary embolism was the highest cause of perinatal
mortality in women. That is improving; whether it is improving
through prophylaxis we do not know, but it is a big issue. I think
the drive to actually make it happen there is because of the young
group of people and the attitudes around that. The rest of it,
the patients are elderly, there is a more heterogeneous group
and a more heterogeneous group of doctors as well.
Q49 Chairman: You are implying basically
that the change in obstetrics has not been through the fact that
there is clear factual evidence, more the client group.
Mrs de Cossart: The client group
in combination with their clinicians, to be fair. The medical
groupthe haematologists and obstetricianshave taken
very seriously the problem they have and it has driven them because
it is in the public domain. The perinatal mortality figures have
been available for a long time now; we stare them in the face.
This is what is happening in your practice and that staring them
in the face has actually driven them to do something about it.
I do not think the evidence for death and complications of thromboembolic
disease in the wider surgical and medical community stares us
in the face.
Q50 Dr Taylor: The ACCP guidelines divide
patients up into moderate risk, high risk and low risk. Are there
well-known guidelines for assessing risks and are those implemented?
If there was an absolute rule that every patient, when they went
in, had to have their risk assessed, would that be one way forward?
Professor Kakkar: If you look
at it for surgical patients where that ACCP analysis is made it
does it on the broad group of patients so, for instance, low risk
surgical patients are those under the age of 40, having a procedure
lasting less than 30 minutes with no other risk factor for thrombosis.
The risk factors are well recognised: obesity, previous history
of thrombosis et cetera. Then you have moderate risk patients:
those over the age of 40, having a procedure lasting greater than
30 minutes, an abdominal operation, or those with a single risk
factor for thrombosis. You have the highest risk patients: those
undergoing major orthopaedic surgery, cancer surgery, over the
age of 40 or anyone with multiple risk factors for the development
of thrombosis. Those are very simple categories which are well
validated that a clinician can quickly apply to determine whether
a patient falls into a certain risk group and based upon which
risk group the patient falls intolow, intermediate or highhe
or she can then turn round and say, "Well, this patient requires
no prophylaxis; this patient requires medium risk prophylaxis
and this person requires high risk". If one tries to go into
very complex risk assessment models the problem is selecting patients
on the basis of those risk assessment models has not been validated
in terms of appropriately defining which patients require prophylaxis
and often they are very complex. If they are very complex, clinicians
will not do them and so it is far better to look at the individual
populations of patients rather than the individual risk for a
patient. We do not know how the individual risk factors for the
single patient interact to give you a numerical risk for DVT.
Q51 Dr Taylor: Should junior doctors
be taught to include in their checking an assessment of this risk?
Or do they?
Mrs de Cossart: They are taught
about it. They will have a lecture on it in medical school. The
question is whether it is forefront in their mind when they are
talking to patients. I think forefront in their mind very often
is what is the percentage risk of wound infection, of failure
of the graft put in or some other thing rather than DVT risk.
You asked about implementation of these things and Ajay has pointed
out the three category risk formula which I think is what most
people would adopt as the most sensible way forward, but in even
broader terms than that there is the question of whether one should
have a blanket position for an anti-DVT process or a selective
one. My experience is that when you do it selectively patients
get missed. If you have it on an elect-out basis rather than an
elect-in basis you do actually catch more patients who require
the prophylaxis so in broad terms I would suggest that we should
perhaps be advising that an anti-DVT prophylaxis is given to all
patients in this category unless the doctor decides it is too
Q52 Dr Taylor: To all patients in which
Mrs de Cossart: Certainly in the
moderate and high risk categories in the concensus documents that
Q53 Chairman: I notice one or two nodding
and one or two shaking their heads. Do you disagree with that,
Mr Warwick: I agree with it to
some extent. If you said that all hip replacements and all knee
replacements should have something then I think that is fine.
However, the problem is that moderate and low riskas Ajay
saidis defined by the risk factors so you have got yourself
into a circular argument there because you only know if you are
at moderate risk or high risk if you have already assessed a list
of risk factors. If you gave a prophylaxis to every single person
who came into hospital and every toe nail avulsion was given five
weeks of prophylaxis you have strayed way beyond cost effectiveness
and you have probably strayed beyond the risk benefit thing as
well and you will have more problems.
Mrs de Cossart: To be fair I did
leave out the low risk one and I said that that is the one where
maybe you would have a problem.
Mr Warwick: We only know they
are low risk if we look at the list of risk factors. Every patient
must have his risk factors ticked off on a box as they come in
because only at that point can you judge if this is low risk,
medium risk or high risk.
Mrs de Cossart: But there would
still be some who would fall out of that category; you will not
have all the factors and you will have to make a clinical judgment
about whether you use it or you do not use it.
Q54 Dr Taylor: Should we go so far as
to recommend that all people on the highest risk level should
have prophylaxis regardless?
Mrs de Cossart: Or should have
a conversation with somebody who says: "Because of your particular
problem I think that is unwise"?
Dr Taylor: One of the most frequent complaints
about the Health Service I getand I get an awful lot of
themis because of poor communication between doctors and
patients. I very much welcome your comments on that.
Q55 Chairman: We hear a lot about MRSA;
how does the problem we have been talking about this morning rank
alongside MRSA in terms of seriousness?
Mrs de Cossart: It is much more
Professor Kakkar: I agree with
that. I saw a report that maybe 5,000 deaths were associated with
MRSA. If you look at the epidemiological calculationsbearing
in mind we no longer do an autopsy on patients who die in hospitalthere
is a suggestion that something between 20,000 and 30,000 patients
a year may be dying of pulmonary embolism. One must be cautious
because we do not have the autopsy driven evidence for that statement
but it appears to be in a much greater ball park and therefore
I think that a lot of these reports still put pulmonary embolism
as the mostor one of the mostimportant avoidable
causes of hospitality mortality.
Q56 Chairman: Asking as a lay personand
forgive the question if it is extremely naíve, which it
probably ispresumably it is much easier to determine a
MRSA cause of death. Am I right in assuming that?
Mrs de Cossart: Yes. There is
a trail of infection analysis which will lead up to that death.
Chairman: Thank you for that. Can I express
on behalf of the Committee our gratitude to you all for an excellent
session. We really are very grateful for the evidence that you
have given. Thank you very much. If you wish to remain for the
remainder of the session you would be very welcome.