First observed during the Roman Empire (199 BCE-500 CE), devices made of metals and leather controlled hemorrhagic bleeding from extremity amputations during combat.1 Later coined the tourniquet, these devices were a first-line life-saving measure. It was not until 1864 that tourniquets became an adjunct for good surgical technique (i.e. creating a bloodless surgical field).1 Fast-forward to modern day and tourniquet usage during podiatric surgical procedures is a widespread practice to facilitate surgical ease and good technique.
Despite advancements over time, the fundamental function of a tourniquet remains the same; to occlude blood flow distal to the application site. There are inherent risks involved when modifying any physiologic process. When dealing with combat situations and a ‘life over limb’ mentality, the risks of tourniquet usage may be negligible compared to the potential benefits. However, when tourniquet use facilitates surgical technique, limb quality and preservation of distal structures are a greater consideration.
With an extensive history of use in surgical specialties, tourniquet complications are well-known and can include: tissue ischemia, nerve injury, implication on infection rates and venous complications including deep vein thrombosis (DVT) and pulmonary embolism (PE).2 To mitigate tourniquet-associated complications, understanding appropriate use and practicing safe application techniques established through evidence-based research is essential.
In the first part of this series of articles examining the literature on tourniquet use in surgery, we will address the relevant indications and contraindications.
How Do Tourniquets Contribute To The Surgical Process?
Primary indications for tourniquet use in the surgical setting include:2
- To limit blood loss/prevent hemorrhage;
- To create a nearly bloodless surgical field;
- Preparation for venipuncture; or
- To confine a bolus of anesthetic in an extremity for intravenous regional anesthesia (IVRA, also known as a Bier Block) of the distal lower extremity.
While the first indication is well-established, the second indication (bloodless surgical field) is dependent on surgeon preference as dictated by perceived surgical outcomes. Some surgeons prefer to operate in a ‘wet field’ (i.e. without tourniquet use) for a variety of reasons and, if trained properly, can have optimal outcomes while avoiding potential tourniquet complications. However, with an estimated 15,000 surgical procedures performed daily using a tourniquet in the U.S., the probability of complications increase.1 The widespread tourniquet use has many potential benefits stemming from a nearly bloodless surgical field such as; decreased operative time, minimized risk of iatrogenic injury/tissue damage and decreased risk of infection.2,3
Key Considerations Regarding Tourniquet Contraindications
Along with the adverse effects observed with improper application/use of a tourniquet, there are associated adverse effects innate to certain circumstances and patient populations with regards to tourniquet use. This makes careful patient selection a key factor in perioperative tourniquet outcome.
Current DVT in the ipsilateral surgical limb is an absolute contraindication for tourniquet use. Relative contraindications for using a tourniquet include: infection; sickle cell hemoglobinopathy; history of DVT/PE; documented hypercoagulability; open fracture; severe crush injuries; ipsilateral vascular graft application or recent revascularization; and peripheral vascular disease (PVD).2
Now let us take a closer look at the individual absolute and relative contraindications for tourniquet use.
What You Should Know About Contraindications Related To DVT, PE And Infection
Deep Vein Thrombosis (DVT). The only definite contraindication to tourniquet use and exsanguination found on literature review is the presence of a DVT, as tourniquet release may precipitate thrombus dislodgement and possible development of a pulmonary embolism (PE).4-6
Infection. The reluctance to use tourniquets in surgical cases with infection stems from the theoretical risk of dissemination of bacteria.6 However, this risk more closely associates with proximal spread of infection secondary to exsanguination rather than use of the tourniquet itself.7 Studies by Eyers and colleagues in 2000 and Wagner and team in 1983 displayed no increase in septic complications due to exsanguination or tourniquet use.4,5 Listed as a relative contraindication, surgeons can still use tourniquets proximal to the site of infection if desired.6
Previous DVT/PE/Hypercoagulability. A history of DVT or PE is a frequently-cited risk factor for subsequent recurrence of these conditions with future surgical procedures.8 The American College of Chest Physicians (ACCP) published a risk stratification to classify patients with regards to venous thromboembolism (VTE) recurrence:9
• High Risk: surgery within three months of the original DVT or PE;
• Moderate Risk: surgery between three and 12 months from the original DVT or PE; and
• Low Risk: surgery longer than 12 months from the original DVT or PE.9
Though foot and ankle procedures have been historically considered lower risk procedures with respect to VTE occurrence, there is still a high rate of VTE recurrence (22 to 29 percent) reported in literature.8 Application and duration of tourniquet use correlates to this development of DVT.10
Relevant Contraindications Related To Sickle Cell Pathology, Trauma And Vascular Disease
Sickle Cell Hemoglobinopathy (Sickle Cell Disease/Trait). In patients with sickle cell disease, circulatory stasis, hypoxia and acidosis beneath and distal to the tourniquet cuff create favorable conditions for the genesis of red cell sickling (precipitating a sickle cell crisis), increasing the risk of thrombosis, infarction and hemolysis.6,11 However, recent literature reviews suggest that, when strictly necessary and with appropriate perioperative measures in place, tourniquet use is relatively safe in most patients with sickle cell disease.12,13 These reviews also supports the notion that individuals with heterozygous gene mutation and sickle cell trait are less predisposed to adverse event risk with tourniquet use than those with sickle cell disease.12,13 It is important to note, though, that these reviews adamantly caution careful perioperative management in this patient group, paying extra attention to maintaining the correct patient temperature, acid-base status and oxygenation during the perioperative period.12,13
Indisputably, there exists some increased risk of provoking intravascular sickling of red blood cells with the use of an arterial tourniquet. Therefore, one should balance the risks of precipitating a sickle crisis from tourniquet use in patients with sickle cell disease against the benefit of operating in a bloodless field.
Open Fractures/Severe Crush Injuries. As one generally observes such injuries with higher energy mechanisms, tourniquet use in open fractures is a relatively contraindicated, as it may hinder the ability to adequately assess the extent and devascularization of the injury.9,14 The hypothesis also exists that, due to the precarious blood supply observed with crush injuries, tourniquet application may result in necrosis of potentially viable tissue.6
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