A 56-year-old female presented to surgical clinic with pain and swelling in left great toe associated with progressive deformity of the toenail for past 6 months. On examination, she had a thick, brittle, deformed nail that was in-growing, and was diagnosed with onychogryphosis. The patient underwent ablation of the nail left great toe and wedge excision of the germinal layer of the nail edges on the medial and lateral sides under local anesthesia. The procedure was performed using a digital tourniquet made from the finger of a sterile surgical glove placed around the great toe base and clamped with an artery forceps. After the procedure, a dressing was applied, and the patient was discharged after 4 hours with instructions to follow up in clinic in 2 days.
Upon presentation to clinic two-days post-discharge, the dressing was removed and revealed that the glove tourniquet was still in place, causing a tight constriction ring at the base of the toe. The toe appeared dusky and swollen and was warm. The tourniquet was immediately removed, and gentle massage of the toe was performed at the constriction site. The patient reported mild hypoesthesia and was able to move the toe. She was prescribed Aspirin 100mg daily and Pentoxifylline 400mg three times per day for 15 days. The dressings were changed daily and frequent follow up was performed. The bluish discoloration of the toe increased progressively followed by skin necrosis. The patient ultimately developed gangrene of the left great toe distal to the site of compression. The care team decided to proceed with amputation at the base of the left great toe.
by Claire Manske, MD
Digital tourniquets are commonplace in surgeries involving fingers and toes. Because digits are highly vascularized structures, digital tourniquets are used to provide hemostasis and a bloodless surgical field during invasive procedures. Although tourniquets placed more proximally around the arm or leg can be used for digital surgery, digital tourniquets are preferred because they can be used in conjunction with local, rather than general, anesthesia and are often better tolerated than a limb tourniquet for long periods. Procedures requiring the use of digital tourniquets are performed in a variety of settings including operating suites, emergency departments, urgent care facilities, and outpatient clinics.
Many different digital tourniquets are in use. Commercially available tourniquets are typically brightly colored silicon rings with attached labels, available sterilely in a variety of sizes, and calibrated to provide a certain applied pressure for different digit sizes. In addition, there are numerous types of self-made tourniquets devised from surgical gloves, elastic catheters (e.g. Penrose drains), and vascular loops, which are often held in place with a surgical clamp.1–4 These self-made tourniquets are often easily available, inexpensive, and effective in achieving hemostasis.
Although the incidence of complications from digital tourniquets is not known, there are abundant case reports in the literature, indicating this is a substantial problem.5–10 Reported complications of digital tourniquets include direct pressure injury to the skin and soft tissues, and ischemic injury resulting in digital necrosis. Arguably the most severe complication of digital tourniquets, ischemic injuries, have two principal causes: 1) excessively high pressure applied by the digital tourniquet or 2) prolonged tourniquet time from inadvertent tourniquet retention.
Regarding tourniquet pressure, a commonly accepted guideline is that extremity tourniquet pressure should not exceed 250 mmHg in the upper extremity and 350 mmHg in the lower extremity;11–15 the pressure required to prevent blood flow in the digits is often even lower because digital artery pressures are lower than arterial pressures in the extremities. Excessive tourniquet pressures cause ischemic injury by vascular compression, which can lead to intimal damage and vascular thrombosis.9,16 Additionally, excessive tourniquet pressure causes direct nerve compression, which can exacerbate the effect of the vascular injury, because the digit becomes insensate and the patient is unable to feel the ischemic pain, even after the local anesthesia has work off, resulting in a “painless ischemia.” Furthermore, as in this case, tourniquets cause ischemic injury when the duration of time they are in place exceeds the permissible ischemia time for the tissue under tourniquet control, as may happen with an inadvertently retained tourniquet. The permissible duration of tourniquet application in the extremities is commonly reported at 1.5 – to 2 hours; however, this limitation is stems largely from the large muscle content in the extremities, as the muscles are highly metabolically active and sensitive to ischemia. Ischemia time in the digits is much typically much longer (12-24 hours) but may be influenced by patient comorbidities; persistent digital ischemia has been reported after as few as 20 minutes of tourniquet time. Moreover, there is likely an interaction between tourniquet pressure and tourniquet time.9 At present, there are no clear guidelines for the permissible ischemia time for a digit.
There are few reported treatments once digital ischemia is established. Most case reports of ischemic injury from retained digital tourniquets describe using medicinal leeches (Hirudo medicinalis) to decrease venous congestion and promote arterial inflow.8 Various vasodilatory and vasoprotective agents have been described for the treatment of digital ischemis resulting from vascular disorders, such as Raynaud’s phenomenon and scleroderma, but it is not clear if these have been used or are effective in tourniquet trauma.17 Because there are no guaranteed interventions once ischemic injury has occurred, prevention is the best intervention.
Approach to Improving Safety
Strategies to minimize the risk of ischemic complications of digital tourniquet focus on addressing the causes described above. There are three main strategies: 1) deciding if a digital tourniquet is needed, 2) avoiding digital tourniquets that apply excessive pressure and 3) instituting systems strategies to prevent tourniquet retention.
Deciding if a Tourniquet is Needed
A digital nerve block using lidocaine with epinephrine is an alternative to the digital tourniquet for maintaining a bloodless surgical field.18 These blocks decrease digital perfusion for 10 to 60 minutes, and normal perfusion is restored in 1-3 hours.19 The anesthesia effect of these blocks is reported to last approximately 5 hours (range 3.8 to 7.7 hours).20 Numerous studies have demonstrated their safety and efficacy in upper and lower extremity digital procedures. 21–27 However, these studies have been conducted in carefully selected patients by experienced extremity surgeons in the controlled setting of the operating room and may not be generalizable to patients with medical comorbidities or other providers in less controlled settings. Some practitioners have advocated against the use of these digital blocks in the emergency room setting and by inexperienced providers.28 Nevertheless, this may be a good alternative to a tourniquet in highly selective situations.
Avoiding Excessive Tourniquet Pressure
The ideal tourniquet would apply the least amount of pressure necessary to provide hemostasis. There is great variation in the amount of pressure applied by different digital tourniquets. Several studies have evaluated the pressure applied by different digital tourniquets, and found that the Penrose drain applied the greatest pressure.15,29,30 Lahham et al investigated the pressure applied from a Penrose drain, clamped rolled glove, unclamped rolled glove and two commercially available tourniquets, the Tourni-cot and the T-ring.15 They found that all methods reliable provided reliable hemostasis, but the Penrose drain and the clamped rolled glove resulted in pressure exceeding the recommended limits for extremity tourniquets, at 727 mmHg and 439 mmHg, respectively. Only the commercially available products produced pressures less than the 250 mmHg recommendation for upper extremity tourniquets. The authors recommend using commercial tourniquets to apply a reliable and safe pressure, and to follow the manufactures’ guidelines for use, especially choosing the correct tourniquet size for different digit sizes to ensure safe tourniquet pressures.
Systems Approaches to Preventing Tourniquet Retention
Several strategies have been proposed to prevent inadvertent retention of digital tourniquets, including the use of brightly colored or labelled tourniquets to promote visibility. Many of the commercially available tourniquets are available in easy-to-see colors, while surgical gloves and Penrose drains are often neutral or flesh colored and therefore less conspicuous.31 Because they may be less noticeable and more likely to be retained, some studies have advised against using a sterile glove as a tourniquet.7 Moreover, the National Patient Safety Agency in the United Kingdom issued guidelines recommending against the use of surgical gloves as tourniquets, following a report of 15 incidents of forgotten digital tourniquets.32
Ultimately, however, systemic processes need to be implemented to prevent adverse event occurrence, rather than relying on a single visual cue or person. Many processes and procedures to promote patient safety in the operating room setting may be applied to other settings to decrease the risk of tourniquet retention. One such process is the surgical count, the manual process of counting the materials used in the surgical field, including objects that were used on or in the patient but should not be retained. This typically this includes surgical sponges and needles but can include tourniquets. After the count is performed, the result is announced so the entire team involved in the procedure is aware. The surgical procedure cannot be concluded until all foreign objects are accounted for and the surgical count is correct. Second, announcing the tourniquet start and end time is standard practice when extremity tourniquets are used in surgical procedures. The duration of tourniquet time is then calculated. This is another check against a retained tourniquet, because once the tourniquet time is started, the procedure cannot end until tourniquet time has ended. Third, a sign out procedure is performed at the conclusion of the case by the surgeon and the operating room team; the process reviews the procedure performed and the implants retained with the patient, and is intended to ensure all necessary components of the procedure were performed at that all objects remaining with the patient are intentional. It also provides an opportunity for all members of the team to communicate regarding the procedure and patient safety.
In this case, several factors likely contributed to this patient’s digital ischemic injury. First, the use of a self-made tourniquet likely applied excessive pressure, which caused vascular injury and resultant ischemia. Moreover, using a self-made tourniquet likely increased the risk of accidental retention leading to prolonged ischemia time. Secondly, systemic processes and procedural checks, used to minimize the risk of adverse events and promote team communication, were not in place. Because there are no known reliable interventions to reverse digital ischemia once it occurs, these processes are essential to prevent this catastrophic complication.
- Appropriately sized, brightly colored digital tourniquets that are calibrated to provide a safe pressure are recommended to minimize the risk of accidental retention.
- Avoid use of self-made tourniquets from gloves and elastic catheters, which may apply excessive pressure and be more easily retained.
- Institute a surgical count process at the conclusion for each procedure for all that should not be retained with the patient, including tourniquets.
- Document tourniquet start time, end time, and duration of tourniquet application to ensure tourniquets are removed in timely manner.
- There are no guaranteed interventions to reverse ischemic injury once it has occurred, so prevention is paramount.
Claire Manske, MD
Department of Orthopedic Surgery
UC Davis Health
Shriners Hospital for Children – Northern California
- Harrington AC, Cheyney JM, Kinsley-Scott T, Willard RJ. A novel digital tourniquet using a sterile glove and hemostat. Dermatol Surg Off Publ Am Soc Dermatol Surg Al. 2004 Jul;30(7):1065–7.
- Osanai T, Ogino T. Modified digital tourniquet designed to prevent the tourniquet from inadvertently being left in place after the end of surgery. J Orthop Trauma. 2010 Jun;24(6):387–8.
- Smith IM, Austin OMB, Knight SL. A simple and fail safe method for digital tourniquet. J Hand Surg Edinb Scotl. 2002 Aug;27(4):363–4.
- Tang WYM. A latex finger strip and nylon zip-tie combo as a tunable digital tourniquet. Dermatol Surg Off Publ Am Soc Dermatol Surg Al. 2007 Jun;33(6):713–5.
- de Boer HL, Houpt P. Rubber glove tourniquet: perhaps not so simple or safe? Eur J Plast Surg. 2007 Sep 1;30(2):91–2.
- Haas F, Moshammer H, Schwarzl F. [Iatrogenic necrosis of the large toe after tourniquet placement--clinical course and reconstruction]. Chir Z Alle Geb Oper Medizen. 1999 May;70(5):608–10.
- Selvan D, Harle D, Fischer J. Beware of finger tourniquets: a case report and update by the National Patient Safety Agency. Acta Orthop Belg. 2011 Feb;77(1):15–7.
- Durrant C, Townley W, Ramkumar S, Khoo C. Forgotten Digital Tourniquet: Salvage of an Ischaemic Finger by Application of Medicinal Leeches. Ann R Coll Surg Engl. 2006 Sep;88(5):462–4.
- Dove AF, Clifford RP. Ischaemia after use of finger tourniquet. Br Med J Clin Res Ed. 1982 Apr 17;284(6323):1162–3.
- Avci G, Akan M, Yildirim S, Aköz T. Digital neurovascular compression due to a forgotten tourniquet. Hand Surg Int J Devoted Hand Up Limb Surg Relat Res J Asia-Pac Fed Soc Surg Hand. 2003 Jul;8(1):133–6.
- Wheeless’ Textbook of Orthopaedics [Internet]. Wheeless Online. [cited 2020 Jul 19]. Available from: http://www.wheelessonline.com/
- Sharma JP, Salhotra R. Tourniquets in orthopedic surgery. Indian J Orthop. 2012;46(4):377–83.
- Giannestras NJ, Cranley JJ, Lentz M. Occlusion of the tibial artery after a foot operation under tourniquet: a case report. J Bone Joint Surg Am. 1977 Jul;59(5):682–3.
- Tejwani NC, Immerman I, Achan P, Egol KA, McLaurin T. Tourniquet cuff pressure: The gulf between science and practice. J Trauma. 2006 Dec;61(6):1415–8.
- Lahham S, Tu K, Ni M, Tran V, Lotfipour S, Anderson CL, et al. Comparison of pressures applied by digital tourniquets in the emergency department. West J Emerg Med. 2011 May;12(2):242–9.
- Naim S, Srinivasan MS. Digital tourniquets: a comparative analysis of pressures and pain perception. Acta Orthop Belg. 2008 Apr;74(2):195–9.
- McMahan ZH, Wigley FM. Raynaud’s phenomenon and digital ischemia: a practical approach to risk stratification, diagnosis and management. Int J Clin Rheumatol. 2010;5(3):355–70.
- Lalonde DH, Wong A. Dosage of local anesthesia in wide awake hand surgery. J Hand Surg. 2013 Oct;38(10):2025–8.
- Ilicki J. Safety of Epinephrine in Digital Nerve Blocks: A Literature Review. J Emerg Med. 2015 Nov;49(5):799–809.
- Alhelail M, Al-Salamah M, Al-Mulhim M, Al-Hamid S. Comparison of bupivacaine and lidocaine with epinephrine for digital nerve blocks. Emerg Med J EMJ. 2009 May;26(5):347–50.
- Lalonde D. Minimally invasive anesthesia in wide awake hand surgery. Hand Clin. 2014 Feb;30(1):1–6.
- Lalonde D, Martin A. Epinephrine in local anesthesia in finger and hand surgery: the case for wide-awake anesthesia. J Am Acad Orthop Surg. 2013 Aug;21(8):443–7.
- Lalonde D, Bell M, Benoit P, Sparkes G, Denkler K, Chang P. A multicenter prospective study of 3,110 consecutive cases of elective epinephrine use in the fingers and hand: the Dalhousie Project clinical phase. J Hand Surg. 2005 Sep;30(5):1061–7.
- Denkler K. A comprehensive review of epinephrine in the finger: to do or not to do. Plast Reconstr Surg. 2001 Jul;108(1):114–24.
- Krunic AL, Wang LC, Soltani K, Weitzul S, Taylor RS. Digital anesthesia with epinephrine: an old myth revisited. J Am Acad Dermatol. 2004 Nov;51(5):755–9.
- Wilhelmi BJ, Blackwell SJ, Miller JH, Mancoll JS, Dardano T, Tran A, et al. Do not use epinephrine in digital blocks: myth or truth? Plast Reconstr Surg. 2001 Feb;107(2):393–7.
- Altinyazar HC, Ozdemir H, Koca R, Hoşnuter M, Demirel CB, Gündoğdu S. Epinephrine in digital block: color Doppler flow imaging. Dermatol Surg Off Publ Am Soc Dermatol Surg Al. 2004 Apr;30(4 Pt 1):508–11.
- Lee J, Crane S. Lidocaine with epinephrine for digital nerve blocks: a note of caution. Emerg Med J EMJ. 2010 Apr;27(4):335.
- Hixson FP, Shafiroff BB, Werner FW, Palmer AK. Digital tourniquets: A pressure study with clinical relevance. J Hand Surg. 1986 Nov;11(6):865–8.
- Middleton SD, Jenkins PJ, Muir AY, Anakwe RE, McEachan JE. Variability in local pressures under digital tourniquets. J Hand Surg Eur Vol. 2014 Jul;39(6):637–41.
- Lamont T, Watts F, Stanley J, Scarpello J, Panesar S. Reducing risks of tourniquets left on after finger and toe surgery: summary of a safety report from the National Patient Safety Agency. BMJ. 2010 Apr 21;340:c1981.
- National Patient Safety Agency rapid response report: reducing the risk of tourniquets left on after finger and toe surgery. National Patient Safety Agency, 2009a. https://marmed.com/wp-content/uploads/2019/08/NRLS-1153A-RRR-Tourniquet-mation-2009.12.09-v1.pdf