Surgical Tourniquets and Cerebral Emboli

Osteoarthritis Clinical Trial

Official title:

Surgical Tourniquets and Cerebral Emboli Pilot Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02240732
• Other study ID #: STCE2.0
• Status: Completed
• Phase: N/A
• First received: September 15, 2014
• Last updated: June 28, 2015
• Start date: September 2014
• Est. completion date: April 2015

Study information

• Verified date: June 2015
• Source: University Hospitals Coventry and Warwickshire NHS Trust
• Contact: n/a
• Is FDA regulated: No
• Health authority: United Kingdom: Department of Health
• Study type: Observational

Clinical Trial Summary

BACKGROUND In 2012 76,497 primary total knee (TKR) replacements were performed in England, Wales and Northern Ireland . Traditionally TKR surgery is undertaken with the aid of a surgical tourniquet. A surgical tourniquet is an occlusive device applied around a patient's leg. The tourniquet squeezes the leg (including blood vessels within the leg) and can therefore reduce the amount of bleeding that occurs while it is inflated. An intraoperative tourniquet can therefore help to improve the surgical field of view. Although the majority of surgeons prefer to undertake TKR surgery using a tourniquet a small but increasing number are now not pursuing these devices.

There is robust evidence that the risk of deep vein thrombosis is increased if a tourniquet is used for TKR surgery. In addition embolic material in the venous system have been observed following TKR surgery and have been noted to be present in the right atrium with transoesophageal (TOE) echo intra-operatively. , Significant and potentially life threatening emboli have been documented to enter the cerebral circulation via pulmonary arterio-venous shunts and patent foramen ovale (PFO) (27% of patients at autopsy) , . The clinical manifestations of cerebral emboli post tourniquet deflation in TKR are not fully understood. Fat embolism syndrome and post-operative confusion in TKR patients may be the result of emboli formed during a TKR. ,

AIM

• Is there evidence of emboli entering the cerebral circulation following tourniquet deflation in TKR surgery?

• Is there evidence of MRI detectable brain lesions and or any clinical change in cognition compared in patients undergoing TKR surgery with a tourniquet compared to those that do not have a tourniquet?

Recruitment information / eligibility

• Status: Completed
• Enrollment: 12
• Est. completion date: April 2015
• Est. primary completion date: April 2015
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• i.Aged >18

• ii.Undergoing elective TKR

• iii.Able to give written informed consent

• iv.No contraindications to MR imaging

Exclusion Criteria:

• i. Ages <16

• ii. Not able to give written informed consent

• iv. Contraindications to MR imaging

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• Osteoarthritis
• RA
• Trauma

Locations

Country	Name	City	State
United Kingdom	University Hospital Warwickshire and Coventry	Coventry

Sponsors (1)

Lead Sponsor	Collaborator
University Hospitals Coventry and Warwickshire NHS Trust

Country where clinical trial is conducted

United Kingdom, 

References & Publications (7)

Arroyo JS, Garvin KL, McGuire MH. Fatal marrow embolization following a porous-coated bipolar hip endoprosthesis. J Arthroplasty. 1994 Aug;9(4):449-52. — View Citation

Caillouette JT, Anzel SH. Fat embolism syndrome following the intramedullary alignment guide in total knee arthroplasty. Clin Orthop Relat Res. 1990 Feb;(251):198-9. — View Citation

Parmet JL, Berman AT, Horrow JC, Harding S, Rosenberg H. Thromboembolism coincident with tourniquet deflation during total knee arthroplasty. Lancet. 1993 Apr 24;341(8852):1057-8. — View Citation

Parmet JL, Horrow JC, Pharo G, Collins L, Berman AT, Rosenberg H. The incidence of venous emboli during extramedullary guided total knee arthroplasty. Anesth Analg. 1995 Oct;81(4):757-62. — View Citation

Pugsley W, Klinger L, Paschalis C, Treasure T, Harrison M, Newman S. The impact of microemboli during cardiopulmonary bypass on neuropsychological functioning. Stroke. 1994 Jul;25(7):1393-9. — View Citation

Riding G, Daly K, Hutchinson S, Rao S, Lovell M, McCollum C. Paradoxical cerebral embolisation. An explanation for fat embolism syndrome. J Bone Joint Surg Br. 2004 Jan;86(1):95-8. — View Citation

Tai TW, Lin CJ, Jou IM, Chang CW, Lai KA, Yang CY. Tourniquet use in total knee arthroplasty: a meta-analysis. Knee Surg Sports Traumatol Arthrosc. 2011 Jul;19(7):1121-30. doi: 10.1007/s00167-010-1342-7. Epub 2010 Dec 15. Review. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Number of Emboli on Transcranial Doppler	2 independent technicians will verify the number of emboli detected. Non-invasive	Intra-operative	No
Primary	MRI brain scan - presence of Emboli	Reviewed by Professor of radiology - presence, number and volume of diffusion weighted lesions	Post-operatively, prior to discharge	No
Secondary	Mini-mental state examination	Set of 30 questions which test cognitive function	Pre-operative vs Post-operative	No