Correlation between activated partial thromboplastin time and anti-Xa activity in patients who received low-molecular weight heparin as anticoagulation for haemodialysis

SummaryThe neutralisation by protamine sulphate (PS) of heparan sulphate (HS), a low molecular weight heparin (LMWH), and a reference preparation of unfractionated heparin (UH), was studied by activated partial thromboplastin time (APTT) and anti-Xa clotting assays. UH was most easily neutralised in the APTT assay by PS (on a weight for weight basis), followed by LMWH and HS. The neutralisation of APTT activity by PS closely followed the loss of activity in the anti-Xa clotting assay, when plasma was used as the source of At III. When the anti-Xa clotting assay was carried out using purified At III in place of plasma, HS and LMWH were neutralised by much lower amounts of PS and resembled UH neutralisation more closely. Resistance of HS anti-Xa activity to PS neutralisation decreased with increasing plasma dilution. The presence of bovine albumin with purified At III concentrate increased the resistance of HS to PS neutralisation. It is concluded that PS binding to UH, HS and LMWH is probably related more to their degree of sulphation than molecular weight and that non-specific interactions between PS and plasma proteins inhibit the binding of PS to HS and LMWH.

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Low- and Medium-molecular-weight Hydroxyethyl Starches

Anesthesiology ◽

10.1097/00000542-200011000-00016 ◽

2000 ◽

Vol 93 (5) ◽

pp. 1231-1237 ◽

Cited By ~ 70

Author(s):

Marina Jamnicki ◽

Thomas Bombeli ◽

Burkhardt Seifert ◽

Andreas Zollinger ◽

Vladimir Camenzind ◽

...

Keyword(s):

Molecular Weight ◽

Von Willebrand Factor ◽

Partial Thromboplastin Time ◽

Maximum Amplitude ◽

Activated Partial Thromboplastin Time ◽

Low Molecular Weight ◽

Angle Alpha ◽

Molar Substitution ◽

Von Willebrand ◽

Willebrand Factor

Background High-molecular-weight hydroxyethyl starch (HES) compromises blood coagulation more than medium-molecular-weight HES. The authors compared medium molecular weight HES (200 kd [HES200]) and low-molecular-weight HES (70 kd [HES70]). Methods In a prospective, double-blind, randomized-sequence crossover study, 22 male volunteers received 15 ml/kg HES200 and HES70. Blood samples were taken before and 5 min, 30 min, 1 h, 2 h, 4 h, 8 h, and 24 h after infusion. The following parameters were analyzed at all time points: prothrombin time, activated partial thromboplastin time, fibrinogen, factor VIII, antigenetic and functional von Willebrand factor, platelets, Thrombelastograph analysis parameters (reaction time, coagulation time, maximum amplitude, angle alpha, and clot lysis 30 and 60 min after maximum amplitude), ionized calcium, hematocrit, HES plasma concentration, molecular weight (weight average and number average), molar substitution, and polydispersity (weight average/number average). Repeated-measures analysis of variance (P < 0.05) was used to compare the response of the aforementioned parameters to the infusion of HES70 and HES200. Results Both HES solutions had a significant impact on all parameters. A slightly greater compromise with HES200 was found in activated partial thromboplastin time (P = 0.010), factor VIII (P = 0.009), antigenetic von Willebrand factor (P = 0.041), functional von Willebrand factor (P = 0.026), maximum amplitude (P = 0.008), and angle alpha (P = 0.003). No difference was established with the other parameters. HES concentration (P < 0.001), weight average (P < 0.001), number average (P < 0.001), and polydispersity (P < 0.001) were higher with HES200. There was no difference with molar substitution (P = 0.091). Conclusions Low-molecular-weight hydroxyethyl starch (70 kd) compromises blood coagulation slightly less than HES200, but it is unclear whether this is clinically relevant.

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Low-molecular-weight heparin and partial thromboplastin time-adjusted unfractionated heparin in thromboprophylaxis after total knee and total hip arthroplasty

The Journal of Arthroplasty ◽

10.1016/s0883-5403(98)90096-1 ◽

1998 ◽

Vol 13 (2) ◽

pp. 180-185 ◽

Cited By ~ 9

Author(s):

Christof Paul Rader ◽

Christian Kramer ◽

Achim König ◽

Christian Hendrich ◽

Jochen Eulert

Keyword(s):

Molecular Weight ◽

Total Hip Arthroplasty ◽

Unfractionated Heparin ◽

Hip Arthroplasty ◽

Partial Thromboplastin Time ◽

Low Molecular Weight Heparin ◽

Low Molecular Weight ◽

Total Hip ◽

Total Knee

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Audit of Anticoagulation After Embolectomy for Acute Ischaemia

Annals of The Royal College of Surgeons of England ◽

10.1308/003588409x432329 ◽

2009 ◽

Vol 91 (6) ◽

pp. 470-472 ◽

Cited By ~ 1

Author(s):

T Robinson ◽

I Hunter ◽

R Wathes ◽

D Keeling ◽

L Hands

Keyword(s):

Molecular Weight ◽

Surgical Procedures ◽

Medical Records ◽

Low Molecular Weight Heparin ◽

Activated Partial Thromboplastin Time ◽

Current Evidence ◽

Low Molecular Weight ◽

Junior Doctors ◽

Acute Ischaemia ◽

User Friendly

INTRODUCTION Intravenous unfractionated heparin (UFH) is routinely used in patients after arterial embolectomy. Achieving and maintaining therapeutic levels requires a co-ordinated approach which may be difficult for busy junior doctors and laboratories. There is no current evidence regarding the use of subcutaneous low molecular weight heparin (LMWH) as an alternative. PATIENTS AND METHODS The study retrospectively examined all patients who had undergone any form of embolectomy during 2006 and 2007 by review of their medical records, an electronic laboratory database, and the patients' drug charts. RESULTS Overall, 45 patients were studied. A total of 389 activated partial thromboplastin time (APTT) tests were performed of which 146 (37.6%) were in the therapeutic range (50–90 s), 40.4% were < 50 s and 22.1% were > 90 s. Five patients (11.1%) had further surgical procedures. Significant bleeding occurred in two patients. CONCLUSIONS The results indicate that many patients are not appropriately anticoagulated. Whilst a new UFH protocol is being developed by our hospital trust, the authors believe the use of LMWH could provide a more effective and user-friendly alternative to UFH.

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Iliopsoas hematoma associated with low-molecular-weight heparin use: A case report

SAGE Open Medical Case Reports ◽

10.1177/2050313x20931680 ◽

2020 ◽

Vol 8 ◽

pp. 2050313X2093168

Author(s):

Shangxiang Liu ◽

Chengqing Mei ◽

Hui Zou ◽

Xiaoliang Chang ◽

Zhenglong Ye

Keyword(s):

Computed Tomography ◽

Molecular Weight ◽

Low Molecular Weight Heparin ◽

Anticoagulation Therapy ◽

Activated Partial Thromboplastin Time ◽

Low Molecular Weight ◽

Close Monitoring ◽

Productive Cough ◽

Computed Tomography Scan ◽

Tomography Scan

Iliopsoas hematoma is an uncommon clinical entity that may develop in association with anticoagulation states, coagulopathies and hemodialysis, or anticoagulant therapy. Here, we report a case of unilateral iliopsoas hematoma in a 60-year-old man who received low-molecular-weight heparin for anticoagulation due to continuous veno-venous hemofiltration. The patient presented with fever and productive cough for 2 days. He received continuous veno-venous hemofiltration due to rising blood urea nitrogen (22.7 mmol/L; normal references: 3.2–7.1 mmol) and creatinine (1345 µmol/L; normal references: 53–106 µmol/L). Low-molecular-weight heparin (enoxaparin, 3500–5500 Da, 5–10 IU/kg/h) was delivered continuously by pumps for anticoagulation therapy. At day 12 post heparin treatment, the patient complained left back pain. Platelet count (243 × 109/L) was normal, but both activated partial thromboplastin time (67.5 s) and prothrombin time (17.3 s) were prolonged. Abdominal computed tomography scan revealed left iliopsoas swelling with an indistinct border. Low-molecular-weight heparin was discontinued. Anti-Xa was not monitored throughout the treatment. No improvement was seen, and 3 days later, the patient died after his family decided to terminate therapy. This case highlights the needs for careful anticoagulation as well as close monitoring, and particularly the use of anti-Xa to guide the treatment.

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