  |
|
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Journal of the New Zealand Medical Association,
12-September-2003, Vol 116 No 1181
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Current practice for anticoagulation prophylaxis in inguinal
hernia surgery: a questionnaire survey
Suhail Anwar and Patrick Scott
Thromboembolic disease has long been recognised as a major
cause of post-operative mortality and morbidity. The incidence of deep vein
thrombosis (DVT) in patients having general surgical procedures is quoted to be
about 25%;1 these figures, however, have been
confounded by the different selection criteria used by various large studies in
this field. The THRiFT II consensus group, for instance, quoted a DVT incidence
of 10–80% in general, urological and gynaecological
patients.2,3 Despite the fact that many risk
factors for DVT are known and the efficacy of prophylaxis is well
established,4,5 there are no fixed guidelines
for the use of DVT prophylaxis in various general surgical operations, and
practice varies from surgeon to surgeon. The inconsistent use of DVT prophylaxis
can lead to under or over treatment; the former putting the patient at risk of
post-operative thromboembolic disease,1 and the
latter resulting in undesirable side effects,6
not to mention cost implications.7
MethodsThe majority of the surgeons
practising laparoscopic hernia repairs in the UK are also involved in open
hernia surgery (100% in our study). We therefore used the members of the
Association of Endoscopic Surgeons of Great Britain and Ireland (AESGBI) as a
representative sample for our questionnaire survey. This would give us the
additional benefit of highlighting any difference in practice of anticoagulation
prophylaxis between open and laparoscopic hernia repairs. Figure 1 is the
questionnaire that was posted subsequently to 250 consultant surgeons.
Figure 1. Questionnaire survey sent to surgeons of the
Association of Endoscopic Surgeons of Great Britain and Ireland
(AESGBI)
ResultsIn total, 250 questionnaires were
posted. We received 185 replies out of which three surgeons were already retired
and two could not be located at their particular address. We have therefore
worked out our calculations from a figure of 180 completed replies (72% response
rate).
Ninety nine surgeons (55%) perform laparoscopic repairs for
inguinal hernias and all of them do open hernia repairs as well, whereas 81
surgeons (45%) repair hernias by an open technique only. Out of the 99 that do
laparoscopic hernias, 75 take identical measures for DVT prophylaxis for
laparoscopic and open hernias, whereas 24 differ between prophylaxis for open
and laparoscopic surgery. There is no consistent pattern, but out of these 24,
17 surgeons take slightly more measures for their laparoscopic hernias and 7,
for their open hernias.
Tables 1 and 2 show the methods used for prophylaxis in
laparoscopic and open hernia repairs respectively. As clearly demonstrated by
these figures, there is no predominant method used for prophylaxis, instead the
distribution is random and seems rather empirical. Ten per cent in the
laparoscopic group and 14% in the open group said that the only time they use
pharmacological prophylaxis, with or without any additional measures, is when
the patient is at a high risk of thromboembolic disease post-operatively.
High-risk factors were defined as age over 40 years, previous DVT and
obesity.
Table 1. Prophylactic anticoagulation measures for
laparoscopic repair of inguinal hernia
IPC = intermittent pneumatic compression
*these patients received heparin, with or without
mechanical prophylaxis, only if stratified in high-risk group (heparin could be
unfractionated heparin or low-molecular-weight heparin)
Table 2. Prophylactic anticoagulation measures for open
repair of inguinal hernia
IPC = intermittent pneumatic compression
*these patients received heparin, with or without
mechanical prophylaxis, only if stratified in high-risk group (heparin could be
unfractionated heparin or low-molecular-weight heparin)
We also included a question about the use of DVT prophylaxis
in hernia repairs under local anaesthetic. The results (Table 3) yet again
showed no consistent pattern, with different groups practising various
techniques. Twelve surgeons do not perform hernia surgery under local
anaesthetic. Again 10 (5.6%) use pharmacological prophylaxis only if the patient
is in a high-risk group.
As far as the use of heparins was concerned, in the open
group a total of 100 surgeons use heparins with or without additional measures,
out of which 44 use low-dose unfractionated heparins (UFH) and 56 use
low-molecular-weight heparins (LMWH). These figures were nearly the same for the
laparoscopic hernia repairs.
Table 3. Prophylactic anticoagulation measures for open
repair of inguinal hernia performed under local anaesthetic
IPC = intermittent pneumatic compression
*these patients received heparin, with or without
mechanical prophylaxis, only if stratified in high-risk group (heparin could be
unfractionated heparin or low-molecular-weight heparin)
DiscussionSurveys conducted in the United
States8 and
England9 have shown wide practice variation in
the use of DVT prophylaxis. In 1993 the estimated cost to the National Health
Service of DVT and PE was over £200 million. If all the patients at high
risk of developing post-surgical DVT had received prophylaxis, the NHS would
have saved between £30 million and £80
million.10 On the other hand, use of heparin
(UFH and LMWH) has been reported to be associated with wound complications and
haematomas,6,11,12 resulting in morbidity with
its accompanying financial implications. The rational application of DVT
prophylaxis demands knowledge of risk factors. All surgical patients admitted to
the hospital should be assessed for their risk of DVT with respect to their
medical history, clinical signs, existing conditions and the result of blood
tests. They should than be categorised according to their level of risk and
appropriate prophylaxis given.
The incidence of DVT and PE after inguinal hernia repair is
very low. Dudda and Schunk have quoted a rate of 0.9% for PE and 0.7% for DVT in
their series of 1202 inguinal hernia
operations.13 Kark et al reported one case of
DVT in a review of 1098 hernia repairs under local anaesthetic without any
prophylaxis.14 Begin has reported one case of
DVT from a series of 200 laparoscopic, extraperitoneal inguinal hernia repairs
in France.15 Kopanski et al have shown a
statistically significant difference in the incidence of thrombotic
complications after laparoscopic and open operations with the former being much
lower than the latter.16 Finally, there is
evidence to support the preferred use of LMWH over UFH in general surgery with
respect to better prophylactic efficacy, once-daily injections and cost-saving
implications,17,18 but even this topic is
subject to debate and controversy.
Our study is a very simple one, highlighting the variance
and inconsistency in the use of anticoagulation measures amongst British
surgeons. Although most surgeons are aware of the associated risks and are using
some form of prophylaxis, the pattern is random and inconsistent.
The wide variation shown in our survey reflects the lack of
research on which to base good practice. Some might argue that, due to the very
low rate of DVT in inguinal hernia repair, ‘type’ of prophylactic
measure is not important. We, however, point out that this is a very commonly
performed procedure and lack of risk stratification before instituting
prophylaxis can potentially cause over or under treatment of patients with its
associated cost implications.
Author information:
Suhail Anwar, Specialist Registrar, Department of Surgery, Blackburn Royal
Infirmary, Blackburn, UK; Patrick D Scott, Consultant General Surgeon,
Department of Surgery, Burnley General Hospital, Burnley, UK
Correspondence: Mr S
Anwar, 52 Clockhouse Avenue, Burnley, BB10 2SU, Lancashire, UK. Email: suhail@anwar99.freeserve.co.uk
References:
|
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| | Current
issue | Search journal |
Archived issues | Classifieds
| Hotline (free ads) Subscribe | Contribute | Advertise | Contact Us | Copyright | Other Journals |
|