Letter 2: Use of enoxaparin results in more haemorrhagic complications after breast surgery than...
1
Correspondence The Editors welcome topical correspon- dence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Letter 1: Use of enoxaparin results in more haemorrhagic complications after breast surgery than unfractionated heparin (Br J Surg 2008; 95: 834–836) Sir I read with interest the article by Hardy and colleagues. The authors do not mention how many patients undergoing breast surgery were given 40 mg of enoxaparin. A high body mass index and other high risk factors for deep vein thrombosis 1,2 are also risk factors for breast cancer 3 . If a number of patients received 40 mg, rather than 20 mg, of enoxaparin, this might lead to more incidences of haematoma. Perhaps this is the reason why the results in such surgery differ from others whose patients received 20 mg of enoxaparin instead. W. Kittisupamongkol Hua Chiew Hospital, 665 Bamrungmuang Road, Pomprap, Bangkok 10100, Thailand DOI: 10.1002/bjs.6419 1 Kyrle PA, Eichinger S. Deep vein thrombosis. Lancet 2005; 365: 1163–1174. 2 Blann AD, Lip GY. Venous thromboembolism. BMJ 2006; 332: 215–219. 3 McPherson K, Steel CM, Dixon JM. ABC of breast diseases. Breast cancer – epidemiology, risk factors, and genetics. BMJ 2000; 321: 624–628. Letter 2: Use of enoxaparin results in more haemorrhagic complications after breast surgery than unfractionated heparin (Br J Surg 2008; 95: 834–836) Sir We read with great interest this arti- cle. We congratulate the authors for the well-designed and easily read article. The authors concluded that low molec- ular weight heparin (LMWH) throm- boprophylaxis was associated with a sig- nificant increase in haemorrhagic com- plications after breast surgery compared with unfractionated heparin (UFH). The authors tried to avoid selection bias, but selection of a specific year (because of complete data) cannot guar- antee that there are no significant bleeding complications related to UFH or significant haemorrhagic compli- cations related to LMWH in other years. The authors mentioned that a meta- analysis published in 2001 suggested no significant differences in bleeding complications between the two drugs 1 . Moreover, even in vascular surgery, a comparative study found no difference between enoxaparin and UFH during carotid endarterectomy in periopera- tive bleeding 2 . The authors said that no study comparing haemorrhagic com- plication rates between enoxaparin and UFH has included patients undergo- ing breast surgery, and breast surgery has a relatively high rate of post- operative haemorrhage. The authors did not explain why breast surgery is different from other general sur- gical fields such as hernia or vas- cular surgery as far as thrombopro- phylaxis is concerned. The authors mentioned that only haematomas that required surgical intervention were included in this analysis. However, they did not describe their haemo- static technique and the characteristics of these haematomas in each group (i.e. the size, site, time after surgery, etc.). A. Hussain and H. Mahmood General Surgery Department, Princess Royal University Hospital, Farnborough Common, Orpington, BR6 8ND, UK DOI: 10.1002/bjs.6420 1 Mismetti P, Laporte S, Darmon JY, Buchmuller A, Decousus H. Meta-analysis of low molecular weight heparin in the prevention of venous thromboembolism in general surgery. Br J Surg 2001; 88: 913–930. 2 Assadian A, Kn ¨ obl P, H ¨ ubl W, Senekowitsch C, Klingler A, Pfaffelmeyer N et al. Safety and efficacy of intravenous enoxaparin for carotid endarterectomy: a prospective randomized pilot trial. J Vasc Surg 2008; 47: 537–542. Letter 3: Use of enoxaparin results in more haemorrhagic complications after breast surgery than unfractionated heparin (Br J Surg 2008; 95: 834–836) Sir I read with interest the article by Hardy et al. presenting their retrospective data comparing low molecular weight hep- arin (LMWH) to unfractionated hep- arin (UFH) in breast surgery patients. This is a timely paper that addresses a topical issue in surgical oncology. How- ever, this article also raises a number of issues and I would be very interested in the authors’ opinions regarding the following matters. Firstly, the number (10 of 186 (5·4 per cent)) of postoperative mastec- tomy patients on LMWH requiring an additional surgical intervention for haemorrhage is concerning. A review paper of 33 randomized controlled tri- als involving 33 813 patients undergo- ing general surgical procedures with DVT prophylaxis demonstrated that less than 1 per cent of postoperative patients required a subsequent sur- gical intervention for haemorrhage 1 . Secondly, the conclusion that the rel- ative risk of haematoma was signifi- cantly higher with LMWH than with UFH after breast surgery is in con- trast to a study by Akl and col- leagues who conducted a meta-analysis of 14 randomized clinical trials com- paring LMWH and UFH. This study showed no differences in mortality in patients receiving LMWH com- pared with UFH (relative risk (RR) 0·89; 95 per cent confidence inter- val (c.i.) 0·61–1·28) and there were no differences in rates of pulmonary Copyright 2008 British Journal of Surgery Society Ltd British Journal of Surgery 2008; 95: 1426–1430 Published by John Wiley & Sons Ltd
Transcript of Letter 2: Use of enoxaparin results in more haemorrhagic complications after breast surgery than...
Correspondence
The Editors welcome topical correspon-dence from readers relating to articlespublished in the Journal. Responses shouldbe sent electronically via the BJS website(www.bjs.co.uk). All letters will be reviewedand, if approved, appear on the website. Aselection of these will be edited and publishedin the Journal. Letters must be no morethan 250 words in length.
Letter 1: Use of enoxaparin resultsin more haemorrhagiccomplications after breast surgerythan unfractionated heparin(Br J Surg 2008; 95: 834–836)
SirI read with interest the article by Hardyand colleagues. The authors do notmention how many patients undergoingbreast surgery were given 40 mg ofenoxaparin. A high body mass indexand other high risk factors for deepvein thrombosis1,2 are also risk factorsfor breast cancer3. If a number ofpatients received 40 mg, rather than20 mg, of enoxaparin, this might lead tomore incidences of haematoma. Perhapsthis is the reason why the results insuch surgery differ from others whosepatients received 20 mg of enoxaparininstead.
W. KittisupamongkolHua Chiew Hospital,
665 Bamrungmuang Road, Pomprap,Bangkok 10100, Thailand
DOI: 10.1002/bjs.6419
1 Kyrle PA, Eichinger S. Deep veinthrombosis. Lancet 2005; 365:1163–1174.
2 Blann AD, Lip GY. Venousthromboembolism. BMJ 2006; 332:215–219.
3 McPherson K, Steel CM, Dixon JM.ABC of breast diseases. Breastcancer – epidemiology, risk factors, andgenetics. BMJ 2000; 321: 624–628.
Letter 2: Use of enoxaparin resultsin more haemorrhagiccomplications after breast surgerythan unfractionated heparin(Br J Surg 2008; 95: 834–836)
SirWe read with great interest this arti-cle. We congratulate the authors forthe well-designed and easily read article.The authors concluded that low molec-ular weight heparin (LMWH) throm-boprophylaxis was associated with a sig-nificant increase in haemorrhagic com-plications after breast surgery comparedwith unfractionated heparin (UFH).The authors tried to avoid selectionbias, but selection of a specific year(because of complete data) cannot guar-antee that there are no significantbleeding complications related to UFHor significant haemorrhagic compli-cations related to LMWH in otheryears.
The authors mentioned that a meta-analysis published in 2001 suggestedno significant differences in bleedingcomplications between the two drugs1.Moreover, even in vascular surgery, acomparative study found no differencebetween enoxaparin and UFH duringcarotid endarterectomy in periopera-tive bleeding2. The authors said thatno study comparing haemorrhagic com-plication rates between enoxaparin andUFH has included patients undergo-ing breast surgery, and breast surgeryhas a relatively high rate of post-operative haemorrhage. The authorsdid not explain why breast surgeryis different from other general sur-gical fields such as hernia or vas-cular surgery as far as thrombopro-phylaxis is concerned. The authorsmentioned that only haematomas thatrequired surgical intervention wereincluded in this analysis. However,they did not describe their haemo-static technique and the characteristicsof these haematomas in each group(i.e. the size, site, time after surgery,etc.).
A. Hussain and H. MahmoodGeneral Surgery Department, Princess
Royal University Hospital, FarnboroughCommon, Orpington, BR6 8ND, UK
DOI: 10.1002/bjs.6420
1 Mismetti P, Laporte S, Darmon JY,Buchmuller A, Decousus H.Meta-analysis of low molecular weightheparin in the prevention of venous
thromboembolism in general surgery.Br J Surg 2001; 88: 913–930.
2 Assadian A, Knobl P, Hubl W,Senekowitsch C, Klingler A,Pfaffelmeyer N et al. Safety andefficacy of intravenous enoxaparin forcarotid endarterectomy: a prospectiverandomized pilot trial. J Vasc Surg2008; 47: 537–542.
Letter 3: Use of enoxaparin resultsin more haemorrhagiccomplications after breast surgerythan unfractionated heparin(Br J Surg 2008; 95: 834–836)
SirI read with interest the article by Hardyet al. presenting their retrospective datacomparing low molecular weight hep-arin (LMWH) to unfractionated hep-arin (UFH) in breast surgery patients.This is a timely paper that addresses atopical issue in surgical oncology. How-ever, this article also raises a numberof issues and I would be very interestedin the authors’ opinions regarding thefollowing matters.
Firstly, the number (10 of 186(5·4 per cent)) of postoperative mastec-tomy patients on LMWH requiringan additional surgical intervention forhaemorrhage is concerning. A reviewpaper of 33 randomized controlled tri-als involving 33 813 patients undergo-ing general surgical procedures withDVT prophylaxis demonstrated thatless than 1 per cent of postoperativepatients required a subsequent sur-gical intervention for haemorrhage1.Secondly, the conclusion that the rel-ative risk of haematoma was signifi-cantly higher with LMWH than withUFH after breast surgery is in con-trast to a study by Akl and col-leagues who conducted a meta-analysisof 14 randomized clinical trials com-paring LMWH and UFH. This studyshowed no differences in mortalityin patients receiving LMWH com-pared with UFH (relative risk (RR)0·89; 95 per cent confidence inter-val (c.i.) 0·61–1·28) and there wereno differences in rates of pulmonary
Copyright 2008 British Journal of Surgery Society Ltd British Journal of Surgery 2008; 95: 1426–1430Published by John Wiley & Sons Ltd
