Scandinavian Journal of Clinical and Laboratory Investigation
ISSN: 0036-5513 (Print) 1502-7686 (Online) Journal homepage: http://www.tandfonline.com/loi/iclb20
Thromboplastin activity of blood monocytes after total hip replacement Ø. P. Nygaard & Reikerås To cite this article: Ø. P. Nygaard & Reikerås (1990) Thromboplastin activity of blood monocytes after total hip replacement, Scandinavian Journal of Clinical and Laboratory Investigation, 50:2, 183-186, DOI: 10.1080/00365519009089151 To link to this article: http://dx.doi.org/10.1080/00365519009089151
Published online: 29 Mar 2011.
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Date: 02 April 2016, At: 09:28
Scand J Clin Lab Invest 1990: 50: 183-186
Thromboplastin activity of blood monocytes after total hip replacement
Downloaded by [University of California Santa Barbara] at 09:28 02 April 2016
0.p. N Y G A A R D , K. U N N E B E R G , 0 . REIKERAS & B. @STERUD* Department of Orthopaedic Surgery, Institute of Clinical Medicine and *Institute of Medical Biology, University of Tromso, Tromso, Norway
Nygaard (dP, Unneberg K, Reikerh 0, @sterud B. Thromboplastin activity of blood monocytes after total hip replacement. Scand J Clin Lab Invest 1990; 50: 183-186. Thromboplastin activity of monocytes from blood of seven patients with total hip replacement was investigated. At 24 h and 48 h after surgery, thromboplastin activity was significantly increased compared to the activity before surgery. Thromboplastin activity of endotoxin-stimulated monocytes was significantly increased at 24 h after surgery. There were no significant changes in Factor V after surgery, Factor VII was significantly lowered at 24 h after surgery, while Factor VIII and fibrinogen were significantly increased at 72 h after surgery. The results indicate that monocyte thromboplastin may be a thrombogenic factor after total hip replacement surgery. Key words: monocytes; surgery; thromboplastin activity; thrombosis; total hip replacement 0. Reikeris, MD,Tromsd Universiw Hospital, N-9012 Tromsd, Norway
Surgery is commonly complicated by deep vein thrombosis. The cause of activation of coagulation after surgery is not clear. Thromboplastin (tissue factor) is the initiating substance of the coagulation protease cascade and is the most potent inducer of blood coagulation [l]. Furthermore, it has been established that stimulated monocytes generate a substantial amount of thromboplastin [2]. We have examined thromboplastin activity of blood monocytes as well as some of the clotting factors after total hip replacement (THR) surgery.
MATERIALS AND METHODS Patients The study comprised four female and three male patients who underwent THR according to
the cemented technique. The age of the patients ranged from 60 to 78 years (mean 68 years). All patients had osteo-arthrosis of the hip, but were otherwise healthy and without a history of thrombo-embolic disorders or malignancies. The posterolateral approach to the hip, with the patients lying on their side was used. Dextran 70 (Macrodex 6% with NaCl; Kabi Vitrum, Stockholm, Sweden) was used as thromboprophylaxis according to the following regime: 500 ml during the operation and on the first and third postoperative day. The patients were mobilized on the second postoperative day. In the postoperative period daily clinical observations were made specifically for signs of wound infections and deep vein thrombosis. Venous blood samples were obtained from a cubital vein 5 days before surgery, the morning prior to surgery (but after anaesthesia), 2 h after surgery, and thereafter daily for 4 days. 183
184 0.P Nygaard et al.
Downloaded by [University of California Santa Barbara] at 09:28 02 April 2016
Isolation of mononuclear cells For isolation of mononuclear cells, 1 to 2 ml blood were diluted with equal volume of 0.15 mol/l NaCl and subjected to centrifugation on Lymphopaque (Nyegaard A/S Oslo, Norway) as described by Bpyum [3]. The bands with mononuclear cells were pipetted off, washed with 10 ml 0.15 mol/l NaCl, and cells collected by centrifugation. The cells were resuspended and counted, and the total number of monocytes differentiated as described by Yam [4]. The cellsuspensions were frozen at -70 "C until tested for thromboplastin activity. An assay based on the ability of thromboplastin to accelerate the activation of Factor X by Factor VII was used to measure the thromboplastin activity [l]. To quantify the amount of thromboplastin, different dilutions of crude human brain thromboplastin preparation were tested in the same system, and used as a standard [2]. The thromboplastin activity of the lysed monocytes was then expressed as a percent of our standard preparation. Endotoxin stimulation of blood monocytes Freshly drawn heparinized blood (2 ml) in 1.3 x 8 cm polycarbonate tubes was incubated with Escherichia coli 026: B6 endotoxin (2
mg/ml blood, obtained from Difco Laboratories, Detroit, MI) for 2 h at 37 "C. The mononuclear cells were then immediately isolated, lysed by freezing and thawing, and the thromboplastin activity measured. Clotting assays Factor V, VII and VIII were measured in onestage clotting assays as described by 0sterud et al. [5]. Fibrinogen was quantified according to the method described by Inanda et al. [6]. Statistics Data are expressed by mean k standard error of the mean (SEM). For statistical evaluations the Mann-Whitney U-test was used. A value of p
ISSN: 0036-5513 (Print) 1502-7686 (Online) Journal homepage: http://www.tandfonline.com/loi/iclb20
Thromboplastin activity of blood monocytes after total hip replacement Ø. P. Nygaard & Reikerås To cite this article: Ø. P. Nygaard & Reikerås (1990) Thromboplastin activity of blood monocytes after total hip replacement, Scandinavian Journal of Clinical and Laboratory Investigation, 50:2, 183-186, DOI: 10.1080/00365519009089151 To link to this article: http://dx.doi.org/10.1080/00365519009089151
Published online: 29 Mar 2011.
Submit your article to this journal
Article views: 3
View related articles
Citing articles: 3 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=iclb20 Download by: [University of California Santa Barbara]
Date: 02 April 2016, At: 09:28
Scand J Clin Lab Invest 1990: 50: 183-186
Thromboplastin activity of blood monocytes after total hip replacement
Downloaded by [University of California Santa Barbara] at 09:28 02 April 2016
0.p. N Y G A A R D , K. U N N E B E R G , 0 . REIKERAS & B. @STERUD* Department of Orthopaedic Surgery, Institute of Clinical Medicine and *Institute of Medical Biology, University of Tromso, Tromso, Norway
Nygaard (dP, Unneberg K, Reikerh 0, @sterud B. Thromboplastin activity of blood monocytes after total hip replacement. Scand J Clin Lab Invest 1990; 50: 183-186. Thromboplastin activity of monocytes from blood of seven patients with total hip replacement was investigated. At 24 h and 48 h after surgery, thromboplastin activity was significantly increased compared to the activity before surgery. Thromboplastin activity of endotoxin-stimulated monocytes was significantly increased at 24 h after surgery. There were no significant changes in Factor V after surgery, Factor VII was significantly lowered at 24 h after surgery, while Factor VIII and fibrinogen were significantly increased at 72 h after surgery. The results indicate that monocyte thromboplastin may be a thrombogenic factor after total hip replacement surgery. Key words: monocytes; surgery; thromboplastin activity; thrombosis; total hip replacement 0. Reikeris, MD,Tromsd Universiw Hospital, N-9012 Tromsd, Norway
Surgery is commonly complicated by deep vein thrombosis. The cause of activation of coagulation after surgery is not clear. Thromboplastin (tissue factor) is the initiating substance of the coagulation protease cascade and is the most potent inducer of blood coagulation [l]. Furthermore, it has been established that stimulated monocytes generate a substantial amount of thromboplastin [2]. We have examined thromboplastin activity of blood monocytes as well as some of the clotting factors after total hip replacement (THR) surgery.
MATERIALS AND METHODS Patients The study comprised four female and three male patients who underwent THR according to
the cemented technique. The age of the patients ranged from 60 to 78 years (mean 68 years). All patients had osteo-arthrosis of the hip, but were otherwise healthy and without a history of thrombo-embolic disorders or malignancies. The posterolateral approach to the hip, with the patients lying on their side was used. Dextran 70 (Macrodex 6% with NaCl; Kabi Vitrum, Stockholm, Sweden) was used as thromboprophylaxis according to the following regime: 500 ml during the operation and on the first and third postoperative day. The patients were mobilized on the second postoperative day. In the postoperative period daily clinical observations were made specifically for signs of wound infections and deep vein thrombosis. Venous blood samples were obtained from a cubital vein 5 days before surgery, the morning prior to surgery (but after anaesthesia), 2 h after surgery, and thereafter daily for 4 days. 183
184 0.P Nygaard et al.
Downloaded by [University of California Santa Barbara] at 09:28 02 April 2016
Isolation of mononuclear cells For isolation of mononuclear cells, 1 to 2 ml blood were diluted with equal volume of 0.15 mol/l NaCl and subjected to centrifugation on Lymphopaque (Nyegaard A/S Oslo, Norway) as described by Bpyum [3]. The bands with mononuclear cells were pipetted off, washed with 10 ml 0.15 mol/l NaCl, and cells collected by centrifugation. The cells were resuspended and counted, and the total number of monocytes differentiated as described by Yam [4]. The cellsuspensions were frozen at -70 "C until tested for thromboplastin activity. An assay based on the ability of thromboplastin to accelerate the activation of Factor X by Factor VII was used to measure the thromboplastin activity [l]. To quantify the amount of thromboplastin, different dilutions of crude human brain thromboplastin preparation were tested in the same system, and used as a standard [2]. The thromboplastin activity of the lysed monocytes was then expressed as a percent of our standard preparation. Endotoxin stimulation of blood monocytes Freshly drawn heparinized blood (2 ml) in 1.3 x 8 cm polycarbonate tubes was incubated with Escherichia coli 026: B6 endotoxin (2
mg/ml blood, obtained from Difco Laboratories, Detroit, MI) for 2 h at 37 "C. The mononuclear cells were then immediately isolated, lysed by freezing and thawing, and the thromboplastin activity measured. Clotting assays Factor V, VII and VIII were measured in onestage clotting assays as described by 0sterud et al. [5]. Fibrinogen was quantified according to the method described by Inanda et al. [6]. Statistics Data are expressed by mean k standard error of the mean (SEM). For statistical evaluations the Mann-Whitney U-test was used. A value of p
