Limb surgery requires a bloodless field; blood needs to be shifted from the limb (exsanguination) and an arterial block created by using a pneumatic tourniquet. However, this procedure is not without complications; incomplete exsanguination can lead to pulmonary or cerebral emboli and ineffective cleansing of contaminated equipment can lead to surgical site infection (SSI).

Emboli
Pneumatic tourniquets are thought to cause emboli in two ways¹:

• the increase in compartment pressure as the tourniquet is inflated may dislodge a pre-existing thrombosis
• venous stasis results in local thrombosis which move after deflation of the tourniquet

Zhang et al² undertook a meta-analysis of 13 randomised controlled trials in order to demonstrate the effects of a tourniquet in total knee arthroplasty (TKA). The studies were divided into 2 groups; the tourniquet group (351 knees) and the non-tourniquet group (338 knees). Results showed that the use of a tourniquet increased the risk of thrombotic events (risk ratio (RR), 5.00; 95% CI, 1.31 to 19.10; P = 0.02).

Gavriely’s³ literature review of haemodynamic events around limb exsanguination, tourniquet placement and release during TKA showed; only 70% of the limb’s blood was exsanguinated; that blood remaining inside the vessels of an occluded limb coagulates; that echogenic material, consisting of fresh thrombi, was present in all patients approximately 30 seconds after tourniquet release.

Infection
Despite a plethora of evidence, non-sterile surgical tourniquets and exsanguinators continue to be used. In practice, the tourniquet is usually placed away from the incision site – for example, on the thigh for foot surgery – and covered by a sterile drape which creates a bacterial barrier when intact. However, Blom et al⁴ suggest that organisms such as Staphylococcus epidermidis and Streptococcus sanguis can strike-through dry polyester/cotton drapes within 30 minutes, less if the drapes are soaked with normal saline or blood. Potentially, organisms can contaminate the tourniquet.

Several studies have demonstrated bacterial growth on tourniquets even after disinfection. Brennan et al⁵ (2009) assessed tourniquets and exsanguinators for the presence of bacterial pathogens in 3 orthopaedic hospitals after usual decontamination, which included alcohol-free wipes, 70% isopropyl alcohol-based wipe and Hydrex Surgical Scrub (with tap water and unsterile paper towels). The devices were dried for 15 minutes – exsanguinator inner and outer surfaces were exposed to air approximately every 7 min and then the 4 locations were re-swabbed prior to decontamination. No colony forming units were following decontamination with the non-alcohol based wipes, 1 swab (1/28) produced a positive culture following decontamination with alcohol-based wipes, and 8 of 28 swabs were positive following decontamination with soap and water.
In Thompson et al’s study⁶ of elective orthopaedic lower limb surgery, patients were randomised prospectively to a non-sterile pneumatic tourniquet or sterile elastic exsanguination tourniquet group. Samples were taken from the ties of the non-sterile tourniquet prior to surgery and from the sterile exsanguination tourniquets at the end of the opera¬tion in a sterile fashion. Results showed that of the 34 non-sterile tourniquets sampled prior to surgical application, twenty-three (68%) were contami¬nated with organisms including coagulase-negative Staphylococcus spp, Staphylococcus aureus, Sphin-gomonas paucimobilis, Bacillus spp, and coliforms. In the 36 sterile exsanguination tourniquets used, no contamination was seen.

Gottlieb et al⁷ collected, incubated and sub-cultured 100 reusable tourniquets from a Sydney teaching hospital. Tourniquet colonisation rate was 78%, including non-multi-resistant Gram- positives, Enterococcus species and MRSA amongst those found.

Gavriely and Murdoch’s⁸ position paper included a review of the literature pertaining to contamination of non-sterile reusable pneumatic tourniquet cuffs, which showed that of the studies included, nearly all non-sterile tourniquets were contaminated with pathogens. Another study of the use of tourniquets in total knee arthroscopy⁹ demonstrated that when a non-sterile pneumatic tourniquet was replaced by a sterile elastic exsanguination tourniquet:

• the incidence of surgical site infection reduced from 1.3% to 0.4% (p=0.11)
• the incidence of deep infection was lower in the study group (sterile tourniquet) (0.78%, n=2 vs 2.6%, n=6, p=0.111)
• the incidence of superficial infection was also lower in the study group (0.96%, n=5 vs 4.85%, n=11, p=0.076)

The Solution
A novel product, the HemaClear® sterile, single use only surgical tourniquet has been shown to both reduce the incidence of tourniquet-associated deep vein thrombosis and the incidence of contamination. It is comprised of a silicon ring wrapped in a stockinet sleeve with pull straps and is available in limb circumferences ranging from 14cm – 90cm and a maximum systolic blood pressure under 190mmHg. The size required is determined after measuring the limb circumference at the required occlusion site. After surgical sterile draping, the ring is simply placed on the patient’s fingers or toes and the straps proximally pulled, displacing over 95% of blood from the limb¹⁰. The stockinet sleeve unrolls onto the limb at the same time. The ring acts as the tourniquet, exerting supra-systolic pressure on the limb and blocking arterial blood flow. This process takes less than 12 seconds.

The main practical advantages of this device are:

• Superior exsanguination: The rolling action of the occlusive silicone ring forces 95% of the standing blood out of the surgical field; Esmarch bandages only clear up to 70%
• Creates a sterile field: This sterile, single use tourniquet reduces post-operative infection rates as it eliminates the need for reusable cuffs, which have been shown to be contaminated
• Increases the surgical field: The 1” wide, narrow profile enables a wider and sterile field
• Simple and cost- effective: Easy application reduces preparation time and eliminates the need for tourniquet machines, contaminated reusable cuffs and Esmarch bandages
• Produces axial and radial pressure gradients that result in less force on inner tissue than traditional wide-cuff products

In addition, because of the superior level of exsanguinations, ischaemic by-products stay in the tissue and do not accumulate in the blood. Therefore, when the ring is cut and new blood enters the leg, the ischaemia products are gradually washed, rather than causing sudden flooding of the central circulation and the heart, which can contribute to emboli.

Conclusion
Surgical site infection and post-limb surgery embolus are unwanted. The traditional methods of exsanguinations and arterial block has been shown to be a source of infection and largely ineffective in exsanguination, leading to emboli.

The HemaClear is single-use, easy to use and provides more effective exsanguinations, thereby eliminating side-effects.

For ordering information about the HemaClear – All-in-One Exsanguination Device contact Pentland Medical Ltd.

If you would like to comment on any of the issues raised by this article, particularly from your own experience or insight, Healthcare-Arena would welcome your views.

References

1. Desai S, Prashantha PG, Torgal SV, Rao R. Fatal pulmonary embolism subsequent to the use of Esmarch bandage and tourniquet: A case report and review of literature. Saudi J Anaesth. 2013 Jul-Sep;7(3): 331–335
2. Zhang W, Ning Li N, Chen S, Tan Y. The effects of a tourniquet used in total knee arthroplasty: a meta-analysis. J Orthop Surg Res. 2014; 9:13
3. Gavriely N. Incomplete Leg Exsanguination: A Hemodynamic Cause of Post Total Knee Arthroplasty (TKA) Cognitive Deficit (CD). The Bone and Joint Journal. Volume 95-B, Issue SUPP 15 / March 2013
4. Blom AW, Gozzard C, Heal J, Bowker K, Estela CM. Bacterial strike-through of re-usable surgical drapes: the effect of different wetting agents. J Hosp Infection 2002; 52: 52–5
5. Brennan SA, Walls RJ, Smyth E, et al. Tourniquets and exsanguinators: a potential source of infection in the orthopedic operating theatre? Acta Orthop. 2009 Apr 29; 80(2): 251–255
6. Thompson SM, Middleton M, Forrok M, et al. The effect of sterile versus non-sterile tourniquets on microbiological colonisation in lower limb surgery. 2011. Ann R Coll Surg Engl. 93: 589–590
7. Gottlieb T, Phan T, Cheong EYL, Sala G. Reusable tourniquets. An underestimated means for patient transfer of multi-resistant bacteria. BMC Proc. 2011; 5(Suppl 6): P38
8. Gavriely N, Murdoch L. The Use of Non-Sterile Pneumatic Tourniquets in Limb Operations: A Position Paper. Data on file.
9. Demirkale I, Tecimel O, Hakkan S, et al. Nondrainage Decreases Blood Transfusion Need and Infection Rate in Bilateral Total Knee Arthroplasty. Arthroplasty. 2014. 29(5):993–997
10. Bourquelot P, Levy BI. Narrow elastic disposable tourniquet (Hemaclear®) vs. traditional wide pneumatic tourniquet for creation or revision of hemodialysis angioaccesses. J Vasc Access. 2016 May 7;17(3):205-9