Blood Loss in Total Knee Arthroplasty: A Meta-analysis of 4 Different Tourniquet Protocols

Special Article - Knee Arthroplasty

Austin J Musculoskelet Disord. 2017; 4(1): 1041.

# Blood Loss in Total Knee Arthroplasty: A Meta-analysis of 4 Different Tourniquet Protocols

Boddu C1*, Nett MP2, Cushner FD3 and Scuderi GR4

1Clinical Fellow, NSLIJ Adult Reconstruction/Knee, Lenox Hill Hospital, USA

2Orthopedic Service Line, Northshore Long Island Jewish Health System, USA

3Chief of Orthopedics-Southside Hospital, USA

4Program Director, Orthopedic Service Line, USA

*Corresponding author: Chandrakanth Boddu, Clinical Fellow, NSLIJ Adult Reconstruction/Knee, Lenox Hill Hospital, USA

Received: November 11, 2016; Accepted: February 03, 2017; Published: February 06, 2017

## Abstract

Context: Decreasing perioperative blood loss using a tourniquet during primary total knee arthroplasty (TKA) is a standard practice but there is still no consensus on ideal technique.

Objective: We classified and compared the effect of 4 different tourniquet protocols used in primary TKA.

Data Sources: Pub Med and Embase search was performed the term ‘Tourniquet Blood loss Knee replacement’ to identify original articles.

Study Selection: All the original articles that compared two or more different protocols of tourniquet usage during primary TKA were included. All studies which had an additional variable that would affect perioperative hemoglobin level were excluded.

Data Extraction: Change in the mean hemoglobin level perioperatively when using a specific type of tourniquet was calculated in each study. By combining the results of all studies on each particular type of tourniquet usage, the weighted mean and its variance, standard error, standard deviation and 95% CI were calculated.

Results: 16 studies with a total of 1126 patients were included in metaanalysis. The results of type 2a, type 2b and type 3 techniques of tourniquet usage during primary TKA were essentially comparable. Type 2a, type 2b and type 3 techniques of tourniquet usage were found to have the lowest mean change in the perioperative hemoglobin level and a non overlapping 95% confidence interval of the mean change in the perioperative hemoglobin level compared to type 0 technique of tourniquet usage. Type 1 technique of tourniquet usage had the broadest 95% confidence interval indicating significant individual outliers compared to the rest of the techniques of tourniquet usage during primary TKA.

Conclusion: Type 2a, type 2b and type 3 techniques of tourniquet usage are superior to type 0 and type 1 techniques of tourniquet usage in patients undergoing primary TKA.

Keywords: Knee arthroplasty; Blood Loss; Meta-analysis; Tourniquet protocols

## Introduction

Minimizing perioperative blood loss during total knee arthroplasty (TKA) remains a major concern and the specific tourniquet protocol employed during TKA can affect both intraoperative and total perioperative blood loss. The use of tourniquet remains popular during TKA for the benefits of decreasing immediate intraoperative blood loss and providing a clearer surgical field. However, after deflation of tourniquet, the dual effect of previous ischemia and surgically induced inflammation results in a reflex increase in blood flow and subsequent bleeding. The limb hypothermia caused by tourniquet use may also result in increased bleeding due to dysfunction of coagulatory enzymes. With these adverse effects on hemostasis, the net clinical effect of tourniquet use on perioperative hemoglobin remains undetermined.

Most of the current studies available directly compare only two tourniquet protocols on perioperative blood loss and/or change in perioperative hemoglobin level. The objective of this meta-analysis is to compile and compare the effects of all the currently used tourniquet protocols on perioperative change in hemoglobin level during primary TKA to determine if one protocol is superior.

## Techniques of tourniquet usage

For the purpose of this study we grouped the currently utilized techniques of tourniquet usage during total knee arthroplasty in to 4 types (Table 1). No application or application and but no inflation of tourniquet throughout the procedure was considered type 0. Type 1 technique is inflation of the tourniquet only during fixation of implants using cement and deflation immediately after setting of the cement. Inflation of the tourniquet just before the start of surgery and deflation to achieve hemostasis after fixation of implants and prior to closure of the arthrotomy was considered type 2. Type 2 technique is again subdivided in to two based on whether surgical wound closure was performed without reinflation of tourniquet (type 2a) or with reinflation of tourniquet until completion of the procedure and application of the final dressing (type 2b). Finally, type 3 technique was defined as inflation of the tourniquet just before the start of surgery and deflation after closure of arthrotomy or complete closure of the surgical wound.