The arterial tourniquet: pathophysiological consequences and anaesthetic implications

Clinical Effects of Tourniquet Use for Nontraumatic Major Lower Limb Amputation: A Two-Center Retrospective Cohort Study

BACKGROUND

To investigate the effect of tourniquet use on outcomes after major lower limb amputation (MLLA) due to peripheral arterial disease or complications from diabetes mellitus.

METHODS

In this 2-center retrospective observational study, vascular patients who underwent MLLA between January 1, 2016 and December 31, 2020 at 2 UK hospitals were identified using operating theater databases. Hospital databases were used to access medical records, operation notes, and laboratory reports. The use of a tourniquet in each MLLA was noted. The primary outcome was postoperative hemoglobin (Hb) drop (g/L). Secondary outcomes were units of allogeneic blood transfused perioperatively, 90-day revision rates, 90-day wound breakdown rates, surgical site infection (SSI) rates (at 30 days), and 90-day mortality. A follow-up index (a measure of follow-up completeness) was calculated for all 30-day and 90-day outcomes.

RESULTS

Four hundred seventy two patients underwent MLLA, of which 124 had a tourniquet applied. The median postoperative Hb drop was significantly lower in the tourniquet group compared to the nontourniquet group (13 [interquartile range 5-22] g/L vs. 20 [interquartile range 11-28] g/L; P ≤ 0.001). Thirty three point one percent (41) of tourniquet patients received a blood transfusion perioperatively, compared to 35.6% (124) of nontourniquet patients (P = 0.82). Sixteen percent (76) of patients required surgical revision within 90 days, with no significant difference between the tourniquet and nontourniquet group (20.2% tourniquet vs. 14.7% no tourniquet; P = 0.15). SSI rates (12.0% tourniquet vs. 10.6% no tourniquet, P = 0.66) and 90-day mortality (6.5% tourniquet vs. 10.1% no tourniquet; P = 0.23) were similar. Multivariable regression demonstrated that tourniquet use was independently associated with a reduced hemoglobin drop (β = -4.671, 95% confidence interval -7.51 to -1.83, P ≤ 0.001) but was not associated with wound breakdown, revision surgery, or SSI. Hypertension, SSI, and below-knee amputation using the skew flap technique were all significant predictors of revision surgery. All follow-up indices were ≥ 0.97.

CONCLUSIONS

Tourniquet use in MLLA was associated with a significantly lower fall in postoperative Hb without evidence of harm in terms of SSI, wound breakdown/revision rates, or mortality.

Intraoperative tourniquet-induced hyperthermia in a pediatric patient: a forgotten association -a case report

BACKGROUND

The intraoperative use of tourniquets is associated with several complications, including hyperthermia. We present the first documented case of tourniquet-induced hyperthermia in a pediatric patient at our institution.

CASE

A 5-year-old female with no past medical history underwent tendon release surgery for congenital talipes equinovarus under general anesthesia. Following inflation of a pneumatic tourniquet to a pressure of 250 mmHg on her left thigh, the patient experienced a gradual increase in body temperature. Despite the implementation of cooling measures, the temperature continued to increase until it plateaued. The hyperthermia gradually resolved upon deflation of the tourniquet.

CONCLUSIONS

Tourniquet-induced hyperthermia should be considered as a potential cause of intraoperative hyperthermia, particularly in the absence of typical signs of malignant hyperthermia. Early recognition and appropriate management, including deflation of the tourniquet and implementation of cooling measures, are crucial for preventing potential complications associated with hyperthermia.

Implementing Tourniquet Conversion Guidelines for Civilian EMS and Prehospital Organizations : A Case Report and Review

Since the first documented use of a tourniquet in 1674, the popularity of tourniquets has waxed and waned. During recent wars and more recently in Emergency Medical Services systems, the tourniquet has been proven to be a valuable tool in the treatment of life-threatening hemorrhage. However, tourniquet use is not without risk, and several studies have demonstrated adverse events and morbidity associated with tourniquet use in the prehospital setting, particularly when left in place for more than 2 h. Consequently, the US military's Committee on Tactical Combat Casualty Care has recommended guidelines for prehospital tourniquet conversion to reduce the risk of adverse events associated with tourniquets once the initial hemorrhage has been controlled. Emergency Medical Services systems that operate in rural, frontier, and austere environments, especially those with transport times to definitive care that routinely exceed 2 h, may consider implementing similar tourniquet conversion guidelines.

Cardiovascular Effects of Tourniquet Application with Cardiac Cycle Efficiency: A Prospective Observational Study

Objectives: The impact of the tourniquet on cardiac efficiency remains unknown. This study aimed to assess the impact of the tourniquet on cardiac cycle efficiency (CCE) and to interpret how general anesthesia (GA) or combined spinal epidural anesthesia (CSEA) affects this during surgery using cardiac energy parameters. Methods: This prospective observational study included 43 patients undergoing elective unilateral total knee arthroplasty (TKA) with a tourniquet divided into GA (n = 22) and CSEA (n = 21) groups. Cardiac energy parameters were measured before anesthesia (T1), pre-tourniquet inflation (T2), during inflation (T3-T8), and post-deflation (T9). The estimated power of the study was 0.99 based on the differences and standard deviations in CCE at T2-T3 for all patients (effect size: 0.88, alpha error: 0.05). Results: CCE decreased significantly more at T3 in the GA group than in the CSEA group, whereas dP/dtmax and Ea increased more (p < 0.05, p < 0.001, and p < 0.01, respectively). At T9, CCE increased significantly in the GA group, whereas dP/dtmax and Ea decreased (p < 0.05, p < 0.001, and p < 0.001, respectively). Conclusions: The tourniquet reduces cardiac efficiency through compensatory responses, and CSEA may mitigate this effect.

Randomised controlled trial of tourniquet associated pain generated in lower limb after exsanguination by Esmarch bandage versus limb elevation

BACKGROUND

Tourniquets are common adjuncts in the operating theatre but can be associated with post-operative pain. This study was designed to compare what effect pre-tourniquet Esmarch bandage exsanguination has on pain, compared to pre-tourniquet exsanguination by elevation alone.

METHODS

52 volunteers (104 lower limbs) were included in this study with each volunteer acting as their own matched control. The primary outcome was patient reported pain, measured in both legs simultaneously using area under curve. Secondary outcomes were pain score during inflation and deflation, cumulative pain score, duration of recovery and blood pressure during testing.

RESULTS

Pain after Esmarch was superior to elevation as measured by area under pain curve (68.9 SD 26.1 vs 77.2 SD 27.3, p = 0.0010), independent of leg dominance. Cumulative pain scores demonstrated the same superiority after inflation (50.7 SD 17.1 vs 52.9 SD 17.0, p = 0.026) but not after deflation (p = 0.59). Blood pressure was not significantly different. Time to full recovery of the lower limb was the same for both groups-7.6 min (SD 2.1 min, p = 0.80).

CONCLUSION

Previous studies describe a positive effect on pain when Esmarch bandage was used prior to tourniquet inflation for upper limb. Our findings suggest the same benefit from Esmarch when it was used on lower limbs-particularly during inflation of tourniquet. In addition to pain profiles, surgeon preference and patient factors need to be considered when deciding between elevation and Esmarch bandage.

The past and future of peri-operative interventions to reduce arthrogenic quadriceps muscle inhibition after total knee arthroplasty: A narrative review

Total knee arthroplasty (TKA) improves patient-reported function by alleviating joint pain, however the surgical trauma exacerbates already impaired muscle function, which leads to further muscle weakness and disability after surgery. This early postoperative strength loss indicates a massive neural inhibition and is primarily driven by a deficit in quadriceps muscle activation, a process known as arthrogenic muscle inhibition (AMI). To enhance acute recovery of quadriceps muscle function and long-term rehabilitation of individuals after TKA, AMI must be significantly reduced in the early post-operative period. The aim of this narrative review is to review and discuss previous efforts to mitigate AMI after TKA and to suggest new approaches and interventions for future efficacy evaluation. Several strategies have been explored to reduce the degree of post-operative quadriceps AMI and improve strength recovery after TKA by targeting post-operative swelling and inflammation or changing neural discharge. A challenge of this work is the ability to directly measure AMI and relevant contributing factors. For this review we focused on interventions that aimed to reduce post-operative swelling or improve knee extension strength or quadriceps muscle activation measured by twitch interpolation. For individuals undergoing TKA, the use of anti-inflammatory medications, tranexamic acid, cryotherapy, intra-articular drains, torniquets, and minimally invasive surgical techniques for TKA have limited benefit in attenuating quadriceps AMI early after surgery. However, interventions such as inelastic compression garments, voluntary muscle contractions, and neuro-muscular electrical stimulation show promise in mitigating or circumventing AMI and should continue to be refined and explored.

Tourniquet Use in Extremity-Based Microsurgery

BACKGROUND

 The use of tourniquets and their role in extremity-based microsurgery has not been thoroughly investigated. The purpose of this study was to investigate tourniquet use and its associated outcomes and complications. The authors hypothesize that tourniquets enhance visualization, bloodless approaches to vessel harvest, flap elevation, and anastomosis without added complications.

METHODS

 A retrospective chart review was completed for patients who had undergone extremity-based microsurgery with the use of a tourniquet between January 2018 and February 2022 at two large academic institutions. Demographic characteristics, initial reasons for surgery, complications, and outcomes were recorded. Patients were separated into groups based on tourniquet use during three operative segments: (1) flap elevation, (2) vessel harvest, and (3) microvascular anastomosis. An internal comparison of complication rate was performed between cases for which a tourniquet was used for one operative segment to all cases in which it was not used for the same operative segment. Univariate and multivariate statistical analyses were performed to identify statistically significant results.

RESULTS

 A total of 99 patients (106 surgeries) were included in this study across sites. The mean age was 41.2 years and 67.7% of the patients were male. The most common reason for microsurgical reconstruction was trauma (50.5%). The need for an additional unplanned surgery was the most common surgical complication (16%). A total of 70, 61, and 32% of procedures used a tourniquet for flap elevation, vessel harvest, and for anastomosis, respectively. Statistical analyses identified no difference in complication rates for procedures for which a tourniquet was or was not used for interventions.

CONCLUSION

 Based on these results, the authors state that tourniquets can be utilized for extremity-based microsurgery to enable bloodless dissection without the concern of increased complication rates.

The effect of tourniquet use on postoperative opioid consumption after ankle fracture surgery - a retrospective cohort study

OBJECTIVES

A pneumatic tourniquet is often used during ankle fracture surgery to reduce bleeding and enhance the visibility of the surgical field. Tourniquet use causes both mechanical and ischemic pain. The main purpose of this study was to evaluate the effect of tourniquet time on postoperative opioid consumption after ankle fracture surgery.

METHODS

We retrospectively reviewed the files of 586 adult patients with surgically treated ankle fractures during the years 2014-2016. We evaluated post hoc the effect of tourniquet time on postoperative opioid consumption during the first 24 h after surgery. The patients were divided into quartiles by the tourniquet time (4-43 min; 44-58 min; 59-82 min; and ≥83 min). Multivariable linear regression analysis was used to evaluate the results.

RESULTS

Tourniquets were used in 486 patients. The use of a tourniquet was associated with an increase in the total postoperative opioid consumption by 5.1 mg (95 % CI 1.6-8.5; p=0.004) during the first 24 postoperative hours. The tourniquet time over 83 min was associated with an increase in the mean postoperative oxycodone consumption by 5.4 mg (95 % CI 1.2 to 9.7; p=0.012) compared to patients with tourniquet time of 4-43 min.

CONCLUSIONS

The use of a tourniquet and prolonged tourniquet time were associated with higher postoperative opioid consumption during the 24 h postoperative follow-up after surgical ankle fracture fixation. The need for ethical approval and informed consent was waived by the Institutional Review Board of Northern Ostrobothnia Health District because of the retrospective nature of the study.

Tourniquet use in ankle arthroscopy: A systematic review

BACKGROUND

Ankle arthroscopy is commonly performed using a thigh tourniquet and is thought to improve visibility and reduce operative time. However, the current evidence is unclear as to whether the use of a tourniquet provides these benefits. The aim of this study was to investigate whether there is any clinical benefit of using a tourniquet in ankle arthroscopy.

METHODS

A systematic review following PRISMA guidelines was undertaken. All clinical studies published in Medline, Embase, PubMed and the Cochrane Library Database from inception until January 2023 reporting on the use of a tourniquet in ankle arthroscopy were included.

RESULTS

180 studies were identified of which 3 (164 patients) met the inclusion criteria. All studies showed no statistically significant difference in mean surgical time and complication rate between the tourniquet and non-tourniquet groups. Overall, the quality of the evidence was moderate to poor without data in favour or against the routine use of tourniquets in ankle arthroscopy.

CONCLUSION

The current literature suggests that there are no significant differences in mean surgical time and complication rate between the tourniquet and non-tourniquet groups.

Vascular imaging immediately after tourniquet removal does not increase vasospasm risk

BACKGROUND

Prehospital tourniquet use is now standard in trauma patients with diagnosed or suspected extremity vascular injuries. Tourniquet-related vasospasm is an understudied phenomenon that may confound management by causing erroneous arterial pressure indices (APIs) and abnormalities on computed tomography angiography (CTA) that do not reflect true arterial injuries. We hypothesized that shorter intervals between tourniquet removal and CTA imaging and longer total tourniquet times would be correlated with a higher likelihood of false positive CTA.

MATERIALS AND METHODS

We performed a single-institution retrospective cohort study of patients presenting to a busy, urban Level 1 Trauma Center with prehospital tourniquets from 2019 to 2021. Patients who presented with a tourniquet disengaged upon arrival or who died prior to admission to the Trauma Unit were excluded. Tourniquet duration, time between tourniquet removal and CTA imaging (CTA interval), CTA findings, and management of extremity arterial injuries were extracted. The proportion of false positive injuries on CTA was assessed for correlation with increasing time interval from tourniquet removal to CTA imaging and correlation with increasing total tourniquet time using multivariable logistic regression.

RESULTS

251 patients were identified with prehospital tourniquets. 127 underwent CTA of the affected extremity, 96 patients had an abnormal CTA finding, and 57 (45% of total CTA patients) had false positive arterial injuries on imaging. Using multivariable logistic regression, neither the CTA interval nor the tourniquet duration was associated with false positive CTA injuries. Female sex was associated with false positive injuries on CTA (OR 2.91, 95% CI: 1.01 - 8.39). Vasospasm was cited as a possible explanation by radiologists in 40% of false positive CTA reports.

CONCLUSIONS

Arterial vasospasm is a frequent finding on CTA after tourniquet use for extremity trauma, but concerns regarding tourniquet-related vasospasm should not alter trauma patient management. Neither the duration of tourniquet application nor the time interval since removal is associated with decreased CTA accuracy, and any delay in imaging does not appear to reduce the likelihood of vasospasm. These findings are important for supporting expedited care of trauma patients with severe extremity injuries.

Development of a pain self-management intervention framework for people with spinal cord injury

BACKGROUND

 Pain is the most common reason for medical visits to primary health care practitioners. Pain self-management interventions are encouraged and there is no known self-management intervention framework available that clinicians and people with spinal cord injury (PWSCI) can use to guide treatment selection.

AIM

 This study aimed to develop a pain self-management intervention framework for PWSCI.

SETTING

 Online and facilitated in Gauteng, South Africa.

METHODS

 A three-round modified e-Delphi method was used to reach an 80% consensus among a 21-expert panel. Fifty-nine interventions were distributed via REDCap and a final online audio meeting was held to either include or exclude interventions in the final framework. SPSS v27 was used to analyse descriptive data and content analysis was used for qualitative responses.

RESULTS

 The final developed pain self-management framework consists of 56 interventions and includes interventions from multiple health professions to encompass medical, psychological, therapeutic and social interventions. Interventions are also specified for nociceptive and/or neuropathic pain and grouped according to the biopsychosocial model.

CONCLUSION

 The interprofessional framework may be used as a guideline for PWSCI to alleviate pain, as well as assist health professionals in clinical decision-making, by providing them with the freedom to choose acceptable and adequate interventions that may be appropriate to treat the affected individual's pain.Contribution: Pain management is a basic need at the primary healthcare level and PWSCI need access to the broad range of interventions available to manage their pain. The framework highlights the variety of appropriate interventions to guide both health professionals and PWSCI with pain relief options.

Effect of Tourniquet Deflation on Intracranial Pressure Measured by Ultrasound of the Optic Nerve Sheath Diameter in Patients Undergoing Orthopedic Surgery Under Spinal Anesthesia: An Observational Study

Background Orthopedic surgeries of the lower extremities frequently require exsanguination and the use of pneumatic tourniquets. However, the deflation of the tourniquet is accompanied by predominant metabolic changes such as an increase in PaCO2. Prior studies have reported the existence of a correlation between tourniquet deflation and an increase in intracranial pressure in patients undergoing surgery under general anesthesia. However, there is a dearth of literature demonstrating such relationships among patients undergoing surgery under subarachnoid block in the Indian setting. The present research was conducted to study the variations in intracranial pressure after the deflation of the tourniquet by measuring the optic nerve sheath diameter (ONSD) using ultrasound among patients undergoing orthopedic surgery of the lower limb under spinal anesthesia at a tertiary care hospital in eastern India. Methodology After obtaining clearance from the Institutional Ethics Committee, this prospective observational study was conducted among 45 patients undergoing orthopedic surgeries of the lower limb using a pneumatic tourniquet. Changes in intracranial pressure following tourniquet deflation were recorded by measuring ONSD by ultrasound in these patients. Heart rate (HR), mean arterial pressure (MAP), SpO2, EtCO2, and ONSD were noted 15 minutes before administration of subarachnoid block (T0), just before tourniquet deflation (T1) and at 5, 10, and 15 minutes after tourniquet deflation (T5, T10, and T15, respectively). Results The ONSD varied significantly at each point of observation (p < 0.05). The ONSDs at 5 and 10 minutes after the deflation of the tourniquet were significantly greater than that at T0 (p = 0.002). EtCO2 showed a significant increase compared to baseline values at every point of observation intraoperatively whereas MAP showed a significant decrease (p < 0.05). For all parameters (ONSD, HR, systolic blood pressure, diastolic blood pressure, MAP, and EtCO2), the most significant change in observation was noted at T10, i.e., 10 minutes after the deflation of the tourniquet.   Conclusions The significant finding in this study was that the ONSD measurements recorded by ultrasound were increased after the deflation of the tourniquet and that this change can be attributed to an increase in EtCO2. However, the results obtained cannot be validated outside the present research owing to the observational nature of the study and limited sample size. Thus, it is difficult to arrive at a definitive conclusion. Further large-scale multicentric studies may be needed to substantiate the findings of this study.

Tourniquet Practice Among Orthopaedic Surgeons in Saudi Arabia

Introduction This study aimed to evaluate the knowledge of tourniquet use among orthopedic surgeons in Saudi Arabia and assess the practical aspects of their use of tourniquets and the complications they have experienced in their practices. Materials and methods This cross-sectional study was conducted from December 2022 to February 2023. An online questionnaire was distributed among orthopedic surgeons and trainees in Saudi Arabia, and the surgeons' knowledge of tourniquet use was assessed using 17 questions. To investigate tourniquet usage, the participants were divided into three groups: orthopedic residents, specialists, and consultants. An upper limb cuff pressure (CP) of 200 mmHg and a lower limb CP of 250 mmHg were chosen as the cut-off values, and the doctors' choices were compared against literature recommendations using these measures. Result A total of 205 participants filled out the questionnaires; 130 residents, 15 consultants, and 60 specialists, with more males (175/205) than females responding. One hundred and twenty-one surgeons placed the cuff on patients by themselves, while 50 (24.3%) surgeons asked nurses for aid; 135 (65.6%) of them work in teaching hospitals, while 50 (24.3%) work in community hospitals. The incidence of post-tourniquet syndrome was unrelated to expertise (p=0.12). Conclusion When applied properly, tourniquets prevent excessive bleeding and keep the operative field clean during limb surgeries. This study aims to inspire the orthopedic community to reconsider long-held practices, especially regarding tourniquet pressure. The addition of ligature safety education to orthopedics training and outlining the settings and procedures for applying pressure should also be considered. The orthopedic community should set CP and process criteria to avoid complications. This study showed the importance of modifying the training of orthopedic residents to raise awareness and prevent unpleasant events from occurring.

Reducing Tourniquet Pressures in Hand Surgery: Are Lower Pressures as Effective?

Background  Pneumatic tourniquets are widely used in hand surgery. Elevated pressures can be associated with complications, and thus, guidelines based on patient-specific tourniquet pressures have been recommended. The primary aim of this study was to determine whether lower tourniquet values based on systolic blood pressure (SBP) could be effectively applied in upper extremity surgery. Methods  A prospective case series of 107 consecutive patients undergoing upper extremity surgery with use of a pneumatic tourniquet was performed. Tourniquet pressure used was based on the patient's SBP. The tourniquet was inflated based on our predetermined guidelines: 60 mm Hg was added for SBP < 130 mm Hg, 80 mm Hg for SBP between 131 and 190 mm Hg, and 100 mm Hg for SBP > 191 mm Hg. The outcome measures included intraoperative tourniquet adjustment, surgeon-rated quality of bloodless operative field and complications. Results  The mean tourniquet pressure was 183 ± 26 mm Hg with a mean tourniquet time of 34 minutes (range: 2-120 minutes). There were no instances of intraoperative tourniquet adjustment. The surgeon-rated quality of bloodless operative field was excellent in all patients. No complications were associated with the use of a tourniquet. Conclusion  Tourniquet inflation pressure based on SBP is an effective method to provide a bloodless surgical field in upper extremity surgery at significantly lower inflation pressures than are the current standards.

Combined femoral artery block and femoral nerve block reduces thigh tourniquet-induced hypertension

STUDY OBJECTIVE

Tourniquet hypertension (TH) is thought to be caused by sympathetically mediated C-fibers in the femoral epicardium following prolonged intraoperative inflation of the tourniquet, and we hypothesized that blocking the femoral artery at the same time as a conventional femoral nerve block would reduce the incidence of TH.

DESIGN

A prospective, double-blind, randomized, controlled trial.

SETTING

Operating room and hospital ward in the Third Hospital of Hebei Medical University.

PATIENTS

A total of 72 patients receiving high tibial osteotomy under general anesthesia were recruited from June 2022 to September 2022.

INTERVENTIONS

Patients were randomly assigned to receive either a classical femoral nerve block (CFNB) or a modified femoral nerve block (MFNB). Patients in the CFNB group received a 30 mL of 0.5% ropivacaine femoral nerve block and patients in the MFNB group received a 20 mL of 0.5% ropivacaine femoral nerve block combined with a 10 mL of 0.5% ropivacaine femoral artery block.

MEASUREMENTS

The primary outcome assessed was the incidence of TH. Data on intraoperative esmolol dosage, analgesic effect, complications and hemodynamics during surgery were also recorded.

MAIN RESULTS

Incidence of TH was significantly higher in the CFNB group compared with the MFNB group (71.88% vs 31.25%, P = 0.002). The systolic blood pressure in the CFNB group was significantly higher than that in the MFNB group at 45, 60, 75 and 90 min after tourniquet inflation (P = 0.029, P = 0.020, P = 0.009, P = 0.007). There was also a significant increase in intraoperative esmolol dosage in the CFNB group (65.63 ± 44.15 vs 22.19 ± 33.74, P < 0.001). Postoperative pain scores and patient satisfaction were not statistically significant between the two groups.

CONCLUSIONS

The present study demonstrated that modified femoral nerve block reduced intraoperative esmolol dosage and the incidence of TH.

Systemic glucose-insulin-potassium reduces skeletal muscle injury, kidney injury, and pain in a murine ischaemia-reperfusion model

Glucose-insulin-potassium (GIK) is protective following cardiac myocyte ischaemia-reperfusion (IR) injury, however the role of GIK in protecting skeletal muscle from IR injury has not been evaluated. Given the similar mechanisms by which cardiac and skeletal muscle sustain an IR injury, we hypothesized that GIK would similarly protect skeletal muscle viability. A total of 20 C57BL/6 male mice (10 control, 10 GIK) sustained a hindlimb IR injury using a 2.5-hour rubber band tourniquet. Immediately prior to tourniquet placement, a subcutaneous osmotic pump was placed which infused control mice with saline (0.9% sodium chloride) and treated mice with GIK (40% glucose, 50 U/l insulin, 80 mEq/L KCl, pH 4.5) at a rate of 16 µl/hr for 26.5 hours. At 24 hours following tourniquet removal, bilateral (tourniqueted and non-tourniqueted) gastrocnemius muscles were triphenyltetrazolium chloride (TTC)-stained to quantify percentage muscle viability. Bilateral peroneal muscles were used for gene expression analysis, serum creatinine and creatine kinase activity were measured, and a validated murine ethogram was used to quantify pain before euthanasia. GIK treatment resulted in a significant protection of skeletal muscle with increased viability (GIK 22.07% (SD 15.48%)) compared to saline control (control 3.14% (SD 3.29%)) (p = 0.005). Additionally, GIK led to a statistically significant reduction in gene expression markers of cell death (CASP3, p < 0.001) and inflammation (NOS2, p < 0.001; IGF1, p = 0.007; IL-1β, p = 0.002; TNFα, p = 0.012), and a significant reduction in serum creatine kinase (p = 0.004) and creatinine (p < 0.001). GIK led to a significant reduction in IR-related pain (p = 0.030). Systemic GIK infusion during and after limb ischaemia protects murine skeletal muscle from cell death, kidneys from reperfusion metabolites, and reduces pain by reducing post-ischaemic inflammation.

The right turn around: Penrose tourniquet application in paediatrics

INTRODUCTION

Commercially available tourniquets are ill-suited for paediatric patients with limb circumferences smaller than the required mechanism, forcing surgeons to improvise. This study aimed to quantify pressures exerted by the Penrose tourniquet when applied on a phantom model and evaluate the intra-/inter-rater reproducibility of the technique previously proposed.

METHODS

Eight calibrated pressure sensors were distributed evenly along the inner and outer circumference of a silicon-based model. A 30cm-by-3.2 cm ARGYLE Penrose drain, 4-by-4 gauze, marker and ruler were used. The optimal interval for arterial occlusion was determined to be 70% of limb circumference. The tourniquet was secured using two half-knots formed by gauze.

RESULTS

Two-turns of the tourniquet about the model generated mean pressures (SD) of 209.43 (SD:35.98 mmHg) (95%CI: 195.85-224.00 mmHg) (outer-sensor) and 246.32 (SD:61.92 mmHg) (95%CI: 221.02-273.49 mmHg) (inner-sensor). Three-turns generated mean pressures of 302.07 (SD:23.98 mmHg) (95%CI: 292.29-312.53 mmHg) (outer-sensor) and 314.44 (SD:56.70 mmHg) (95%CI: 291.25-338.25 mmHg) (inner-sensor).

CONCLUSION

The Penrose tourniquet has clinical utility, particularly for patients where commercially available tourniquets are not suitable. Current application techniques generate inconsistent pressures. Using the existing model, further refinement can be done to improve the consistency and safety of the application. We recommend using intervals of slightly more than 70% of limb circumference and only two turns of the Penrose tourniquet during application.

LEVEL OF EVIDENCE

V.

Reducing blood loss during laparoscopic myomectomy using a tourniquet loop around the lower uterine segment

OBJECTIVE

To present a simple and effective hemostatic technique using a tourniquet loop during laparoscopic myomectomy.

DESIGN

Pericervical tourniquet has been proven to be a safe and effective measure to reduce blood loss during open myomectomy. However, the use of a tourniquet in laparoscopic myomectomy has been rarely reported probably because the application is difficult and troublesome. In our technique, a prefabricated tourniquet loop, adapted from a Foley catheter, is applied around the lower segment of the uterus. It is easy to apply a tourniquet loop around the lower uterine segment during laparoscopic myomectomy. There is no need to make a window in the broad ligament to apply a pericervical tourniquet or triple tourniquets. Meanwhile, complete blockage of blood supply from the uterine artery and utero-ovarian anastomoses may ensure better hemostasis.

SETTING

A tertiary hospital.

PATIENT(S)

The patient was a 34-year-old woman with uterine leiomyoma and a desire for future fertility. She had been suffering from urinary frequency and chronic bladder pressure for the past 6 months. Magnetic resonance imaging confirmed 2 intramural masses measuring 96 mm × 91 mm and 25 mm × 13 mm at the anterior uterine wall.

INTERVENTION(S)

Institutional review board and ethics committee approval was obtained. Laparoscopic myomectomy was performed with the application of a tourniquet loop around the lower segment of the uterus (step-by-step video demonstration): homemade tourniquet loop formation using a 14-Fr latex Foley catheter; trocar placement with 2 umbilical ports (10 mm and 5 mm) and a 5-mm port at the lower-left quadrant of the abdomen; application of a tourniquet loop around the lower uterine segment; tumor enucleation and myometrial closure; removal of the tourniquet loop and a check for bleeding; contained specimen extraction via the merged umbilical incision; and inspection of the abdominal cavity and closure of the merged umbilical incision.

MAIN OUTCOME MEASURE(S)

Feasibility of using a tourniquet loop as an effective hemostatic technique in laparoscopic myomectomy.

RESULT(S)

The surgery lasted for approximately 90 minutes, and the tourniquet time was approximately half an hour. The estimated blood loss was only 20 mL. Her hemoglobin value on day 1 after the surgery was 131 g/L, the same as the preoperative level. Pathology confirmed the diagnosis of leiomyoma. The patient was discharged 2 days after the surgery with no complications. During follow-up, the patient reported that there was no discomfort and that her menses were normal. Her fallopian tubes were patent in the hysterosalpingogram. Her ovarian function, which was assessed by serum follicle-stimulating hormone concentration (5.34 mIU/mL) on day 3 of her menstrual cycle and antimüllerian hormone level (2.01ng/mL), was in the normal range. She was suggested to conceive 1 year after the procedure.

CONCLUSION(S)

Application of a tourniquet loop around the lower uterine segment is a simple and effective hemostatic technique during laparoscopic myomectomy. Randomized prospective studies are needed to determine the hemostatic effect of the laparoscopic use of a tourniquet loop and its impact on fertility and ovarian function.

Impact of time and distance on outcomes following tourniquet use in civilian and military settings: A scoping review

BACKGROUND

The last two decades have seen the reintroduction of tourniquets into guidelines for the management of acute limb trauma requiring hemorrhage control. Evidence supporting tourniquet application has demonstrated low complication rates in modern military settings involving rapid evacuation timeframes. It is unclear how these findings translate to patients who have prolonged transport times from injury in rural settings. This scoping review investigates the relationship between time and distance on metabolic complications, limb salvage and mortality following tourniquet use in civilian and military settings.

METHODS

A systematic search strategy was conducted using PubMed, Embase, and SafetyLit databases. Study characteristics, setting, mechanism of injury, prehospital time, tourniquet time, distance, limb salvage, metabolic response, mortality, and tourniquet removal details were extracted from eligible studies. Descriptive statistics were recorded, and studies were grouped by ischemia time (< 2 h, 2-4 h, or > 4 h).

RESULTS

The search identified 3103 studies, from which 86 studies were included in this scoping review. Of the 86 studies, 55 studies were primarily in civilian environments and 32 were based in military settings. One study included both settings. Blast injury was the most common mechanism of injury sustained by patients in military settings (72.8% [5968/8200]) followed by penetrating injury (23.5% [1926/8200]). In contrast, in civilian settings penetrating injury was the most common mechanism (47.7% [1633/3426]) followed by blunt injury (36.4% [1246/3426]). Tourniquet time was reported in 66/86 studies. Tourniquet time over four hours was associated with reduced limb salvage rates (57.1%) and higher mortality rates (7.1%) compared with a tourniquet time of less than two hours. The overall limb salvage and mortality rates were 69.6% and 6.7% respectively. Metabolic outcomes were reported in 28/86 studies with smaller sample sizes and inconsistencies in which parameters were reported.

CONCLUSION

This scoping review presents literature describing comparatively safe tourniquet application when used for less than two hours duration. However, there is limited research describing prolonged tourniquet application or when used for protracted distances, such that the impact of tourniquet release time on metabolic outcomes and complications remains unclear. Prospective studies utilizing the development of an international database to provide this dataset is required.

Characterizing tourniquet induced hemodynamics during total knee arthroplasty using diffuse optical spectroscopy

Tourniquet use creates a reduced blood surgical field during total knee arthroplasty (TKA), however, prolonged ischemia may cause postoperative tourniquet complications. To understand the effects of tourniquet-induced ischemia, we performed a prospective observational study using quantitative broadband diffuse optical spectroscopy (DOS) to measure tissue hemodynamics and water and lipid concentrations before, during, and after tourniquet placement in subjects undergoing TKA. Data was collected for 6 months and, of the total subjects analyzed (n = 24), 22 were primary TKAs and 2 were revision TKA cases. We specifically investigated tourniquet-induced hemodynamics based upon subject-specific tissue composition and observed a significant relationship between the linear rate of deoxygenation after tourniquet inflation and water/lipid ratio (W/L, p < 0.0001) and baseline somatic tissue oxygen saturation, StO2 (p = 0.05). Subjects with a low W/L ratio exhibited a lower tissue metabolic rate of oxygen consumption, (tMRO2 ) (p = 0.008). Changes in deoxyhemoglobin [HbR] (p = 0.009) and lipid fraction (p = 0.001) were significantly different between high and low W/L subject groups during deoxygenation. No significant differences were observed for hemodynamics during reperfusion and total tourniquet time was neither significantly related to the hemodynamic hyperemic response (p = 0.73) nor the time to max StO2 after tourniquet release (p = 0.57). In conclusion, we demonstrate that DOS is capable of real-time monitoring of tissue hemodynamics distal to the tourniquet during TKA, and that tissue composition should be considered. DOS may help surgeons stratify hemodynamics based upon tissue composition and eventually aid the preoperative risk assessment of vascular occlusions from tourniquet use during TKA.

Risk factors for dexmedetomidine-associated bradycardia during spinal anesthesia: A retrospective study

Sedation with dexmedetomidine is needed for patients undergoing spinal anesthesia. However, dexmedetomidine sedation increases the incidence of bradycardia. We aimed to identify and to evaluate risk factors for bradycardia in patients undergoing spinal anesthesia with dexmedetomidine sedation. The records of 91 patients who underwent spinal anesthesia with sedation using dexmedetomidine were reviewed retrospectively. For this study, we identified 15 characteristics of included patients from this group who underwent lower leg surgery and had an estimated blood loss of <300 mL. We collected details on potential risk factors for bradycardia from their clinical records. These factors included age, American Society of Anesthesiologists classification, height, weight, sensory level of spinal anesthesia, history of hypertension, diabetes mellitus, loading, and maintenance dose of dexmedetomidine, tourniquet time, initial diastolic and systolic blood pressure, initial heart rate (HR), and anesthesia and surgery duration. The primary endpoint of this study was the occurrence of bradycardia. We identified potential risk factors using logistic regression analysis. The incidence of bradycardia was obtained in 23 (25%) of 91 patients. Initial HR and tourniquet time were significant individual predictive factors for the occurrence of bradycardia. Logistic regression analysis showed that adjusted baseline HR and duration of tourniquet use were risk factors for bradycardia. Patients should be monitored when undergoing spinal anesthesia with sedation using dexmedetomidine for bradycardia when they have a long tourniquet time. A low initial HR could also be a predictive factor for bradycardia.

Field tourniquets in an austere military environment: A prospective case series

OBJECTIVE

Field tourniquets are often used for battlefield extremity injuries. Their effectiveness has been documented by a large combat theater trauma center. However, their use and effectiveness by an austere forward surgical team has not been reported. Aims of this study were to determine: Whether field tourniquets: (1) Were placed for appropriate indications; (2) significantly reduced hemorrhage as measured by transfusion requirements; (3) influenced vital signs and injury severity scores; and (4) did they cause limb amputation, changed amputation level, or other complications.

METHODS

Twenty-five patients with 30 involved extremities presenting to a forward surgical team in Iraq met the inclusion criteria. We prospectively collected data regarding the presence, indications for, and effectiveness of field tourniquets based on the need for blood transfusion. We recorded any complications associated with their use.

RESULTS

Tourniquets significantly reduced hemorrhage from penetrating injuries as measured by transfusion requirements. Those having major vascular injuries with effective tourniquets, a total of 12 units of blood were transfused (1.7 units/vascular injury; 2 units/patient). However, 19 units were transfused in patients (3.3 units/vascular injury; 3.8 units/patient) who had an ineffective or no tourniquet (p = 0.0006). Transfusion requirements were related the presence of an effective tourniquet regardless of concomitant injuries. The group with effective tourniquets and compressed hemorrhage presented with higher mean systolic (p = 0.003) and diastolic (p = 0.023) blood pressures than the group with no tourniquets or ineffective ones. Complications included one peroneal nerve palsy and no amputations resulted from tourniquet application.

CONCLUSION

Field tourniquets applied for penetrating injuries with severe bleeding can significantly reduce transfusion requirements and help maintain adequate blood pressure. Tourniquets were not the proximate cause of amputation and did not determine the choice of immediate amputation level.

Tourniquet Use During Open Reduction and Internal Fixation of Ankle Fractures - A Systematic Review and Meta-Analysis

The intra-operative use of tourniquet in open reduction and internal fixation (ORIF) of ankle fractures remains a topic of debate. The purpose of this study was to perform a systematic review and meta-analysis of randomized control trials (RCTs) comparing clinical outcomes of patients undergoing ankle ORIF with tourniquet use versus a control group where no tourniquet was used. A systematic review was performed with reference to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines of the Pubmed, Scopus, Embase, and Cochrane Library databases. Studies were included if they were an RCT comparing tourniquet and no-tourniquet in ankle ORIF. Meta-analysis was performed using RevMan, and p-value <.05 was considered to be statistically significant. On completion of the literature search, a total of 4 RCTs including 350 ankles (52.6% males), with a mean age of 47.1 ± 5.7 years were included. There were 173 patients in the tourniquet group (T), versus 177 patients in the no tourniquet control group (NT), with nonsignificant differences between the groups for age, gender and body mass index demographics (all p > .05). There were significantly shorter duration of surgery, with significantly higher patient-reported rates of pain levels at day 2 postoperatively (both p < .001) in the T group. Additionally, there were significantly greater ranges of ankle motion at 6 weeks postoperatively (p = .03), with nonsignificant differences reported incidence of wound infections and deep vein thrombosis (p = .056 and p = .130 respectively) between the groups. In conclusion, current evidence suggests that although intraoperative tourniquet usage in cases of ankle ORIF results in significant reductions in duration of surgery, this may be at the expense of higher patient-reported pain scores and reduced range of motion postoperatively.

Evaluation of the Influence of Short Tourniquet Ischemia on Tissue Oxygen Saturation and Skin Temperature Using Two Portable Imaging Modalities

BACKGROUND

The exact influence of tourniquet ischemia on a treated extremity remains unclear.

METHODS

Twenty patients received an operation on one hand under tourniquet ischemia. Twenty healthy volunteers received 10 min of tourniquet ischemia on one of their arms. Measurements of tissue oxygen saturation using near-infrared reflectance-based imaging and skin temperature of the dorsum of the hand were performed at five different timepoints (t0 was performed just before the application of the tourniquet ischemia, t1 directly after the application of the tourniquet ischemia, t2 before the release of the ischemia, t3 directly after the release of the ischemia, and t4 on the following day).

RESULTS

In both groups, tissue oxygen saturation dropped after the application of the tourniquet ischemia compared to t0 and increased after the release of the tourniquet ischemia. In the patient group, tissue oxygen saturation at t4 was higher compared to t0; in contrast, the level of tissue oxygen saturation in the participant group dropped slightly at t4 compared to t0. The measured skin temperature in the patient group showed an increase during the observation period, while it continuously decreased in the group of healthy participants.

CONCLUSIONS

Short-term ischemia did not appear to permanently restrict perfusion in this study design. The non-invasive imaging modalities used were easy to handle and allowed repetitive measurement.

Efficacy of arterial occlusion pressure estimation-based tourniquet pressure settings in upper limb surgery

BACKGROUND

The use of a minimal individualized effective pneumatic tourniquet pressure is recommended to avoid pressure related complications in extremity surgery. The aim of this study was to investigate the efficacy of arterial occlusion pressure estimation-based tourniquet pressure settings in upper limb surgery.

METHODS

Hundred and fifteen patients undergoing upper limb surgeries were enrolled in the present study. Arterial occlusion pressure estimation formula was used and a safety margin of 20 mmHg was added to arterial occlusion pressure in the tourniquet pressure setting. Primary and secondary endpoints were the amount of tourniquet pressure and its effectiveness respectively. Other outcome measures included the tourniquet pressure setting time and tourniquet related complications. Surgical team unaware of the tourniquet pressure assessed the bloodless surgical field.

RESULTS

The mean initial and maximal tourniquet pressures were 171.5 ± 13.7 and 175.5 ± 13.2 mmHg, respectively. The effectiveness of the tourniquet was rated as "excellent" and "good" in the initial and middle stages, and at the end of the surgery of the procedure in 97.3%, 99.1%, and 100% of cases respectively. The mean tourniquet pressure setting time was 29.0 ± 3.7 s. No tourniquet related complications were observed.

CONCLUSIONS

Arterial occlusion pressure estimation-based tourniquet pressure setting is a practical and effective method, which allows using lower tourniquet pressures than previously used in the literature for upper extremity surgery.

Hyperbaric oxygen therapy does not alleviate tourniquet-induced acute ischemia-reperfusion injury in mouse skeletal muscles

During tourniquet application, blood flow is restricted to a limb to stop excessive limb hemorrhage in a trauma setting and to create a bloodless operating field in the surgical setting. During tourniquet-related ischemia, aerobic respiration stops, and ATP is depleted, and during subsequent reperfusion, there is an increase in reactive oxygen species (ROS) production and other endogenous substances, which leads to acute ischemia-reperfusion (IR) injuries, including tissue necrosis and skeletal muscle contractile dysfunction. Hyperbaric oxygen (HBO) therapy can increase the arterial oxygen tension in the tissues of patients with general hypoxia/anoxia, including carbon monoxide poisoning, circulatory arrest, and cerebral and myocardial ischemia. Here, we studied the protective effects of HBO pretreatment with 100% oxygen at 2.5 ATA against tourniquet/IR injury in mice. After one hour of HBO therapy with 100% oxygen at 2.5 ATA was administered to C57/BL6 mice, a rubber band was placed at the hip joint of the unilateral hindlimb to induce 3 h of ischemia and then released for 48 h of reperfusion. We analyzed gastrocnemius muscle morphology and contractile function and measured the levels of ATP and ROS accumulation in the muscles. HBO pretreatment did not improve tourniquet/IR-injured gastrocnemius muscle morphology and muscle contraction. Tourniquet/IR mice with HBO pretreatment showed no increase in ATP levels in IR tissues, but they did have a decreased amount of ROS accumulation in the muscles, compared to IR mice with no HBO pretreatment. These data suggest that one hour of HBO pretreatment with 100% oxygen at 2.5 ATA increases the antioxidant response to lower ROS accumulation but does not increase ATP levels in IR muscles and improve tourniquet/IR-injured muscle morphology and contractile function.

Change in the optic nerve sheath diameter after deflation of a pneumatic tourniquet: a prospective observational study

Applying a pneumatic tourniquet provides surgeons with a bloodless surgical field. However, application of the tourniquet induces various physiological changes. We evaluated the effect of tourniquet deflation on the intracranial pressure by using ultrasonography to measure the optic nerve sheath diameter (ONSD) in patients undergoing lower limb surgery. The ONSD was measured in 20 patients at five time points: after anesthetic induction (T0) and immediately before (T1), immediately after (T2), 5 min after (T3), and 10 min after tourniquet deflation (T4). Hemodynamic and respiratory variables were recorded. The ONSD showed significant differences at each point (P < 0.001). The ONSDs at T2 and T3 were significantly greater than that at T1 (P = 0.0007 and < 0.0001, respectively). The change in the end-tidal carbon dioxide partial pressure (EtCO2) was similar to the change in the ONSD. The change in the ONSD was significantly correlated with the change in the EtCO2 after tourniquet deflation (r = 0.484, P = 0.030). In conclusion, the ONSD, as an indicator of intracranial pressure, increased after tourniquet deflation in patients undergoing lower limb surgery. This was correlated with an increased EtCO2 and arterial carbon dioxide partial pressure.

Trial registration: ClinicalTrials.gov (NCT03782077).

Treatment of hand infections using WALANT -when the anesthesiologist is not available: A retrospective cohort study

Backround

The aim of this study was to determine, if Wide Awake Local Anesthesia No Tourniquet (WALANT) can be used as an alternative method of providing anesthesia in management of deep infections of the hand. Since the advent of WALANT in 2003, infections of the hand have been regarded as a contraindication to its use. Occasional shortage of anesthesiologic manpower, especially during busy call hours and the current COVID-19 pandemic can lead to delay of treatment where urgent surgery is needed, to prevent progress of an infection, that can result in severe morbidity.

Methods

In the period from 2015 to 2020, 16 patients with various infections of the hand underwent 17 operations using WALANT in a Hand Trauma and Replantation Center (HTRC) in Germany. Retrospective cohort analysis of their operation reports, with emphasis on location of infection, time and duration of the operation, intraoperative incidents and complications were carried out. We also evaluated the need for revision surgery or necessity to convert to general anesthesia and factors causing delay till the time of surgery.

Results

No case of inadequate analgesia, the need to convert to general anesthesia, ischemic events or cardiovascular complications with the use of the WALANT solution containing adrenaline and lidocaine in the treatment of deep tissue infections.

The highest priority of limb preservation was ensured as no patient progressed to amputation of a digit or the hand. There was a statistically significant difference (p≤0.01) in delay from the time of admission until surgery of up to 9h24 m (SD±3h34 m) during the week and 4h10 m (SD±2h28 m) during the weekend.

Conclusion

The status of infection as an absolute contraindication to the use of WALANT should be revised. Especially when human resources are limited, WALANT is an adequate technique to enable quick anesthesia for urgent treatment to prevent progression of hand infections.

•

Wide Awake Local Anesthesia No Tourniquet can be used to treat deep hand infections.

•

In the COVID-19 pandemic alternative ways of providing anesthesia are needed.

•

Absolute contraindication to the use of WALANT should be reevaluated.

•

“time is function”, urgent treatment remains key in management of hand infections.

A comparison of acute mouse hindlimb injuries between tourniquet- and femoral artery ligation-induced ischemia-reperfusion

The tourniquet or femoral artery ligation is widely used to stop extremity hemorrhage or create a bloodless operating field in the combat scenario and civilian setting. However, these procedures with subsequent reperfusion also induce ischemia-reperfusion (IR) injuries. To fully evaluate animal models of limb IR injuries, we compared tourniquet- and femoral artery ligation-induced IR injuries in the hindlimb of mice. In C57/BL6 mice, 3 h of unilateral hindlimb ischemia was induced by placement of a rubber band at the hip joint or a surgical ligation of the femoral artery. The tourniquet or femoral artery ligation was then released, allowing for 24 h of reperfusion. Compared to the femoral artery ligation/IR, the tourniquet/IR induced more severe skeletal muscle damage, including muscle necrosis and interruption of muscle fibers. There was no gastrocnemius muscle contraction in tourniquet/IR, while femoral artery ligation/IR markedly weakened gastrocnemius muscle contraction. Motor nerve terminals disappeared, and endplate potentials (EPPs) were undetectable in tourniquet/IR, whereas femoral artery ligation/IR only induced mild impairment of motor nerve terminals and decreased the amplitude of EPPs. Additionally, western blot data showed that proinflammatory cytokine levels (IL-1β and TNF-α) were higher in the tourniquet/IR than that in femoral artery ligation/IR. Moreover, tourniquet/IR caused significant tissue edema and dilation of lymphatic vessels in the hindlimb, compared to femoral artery ligation/IR. The above data demonstrated that tourniquet/IR-induced acute hindlimb injuries are more severe than those induced by femoral artery ligation/IR. This suggests that future investigators should determine which hindlimb IR model (tourniquet/IR or femoral artery ligation/IR) is optimal depending on the purpose of their study.

Comparison of bolus administration effects of lidocaine on preventing tourniquet-induced hypertension in patients undergoing general anesthesia: a randomized controlled trial

Background

This study assessed the effect of a single bolus administration of lidocaine on the prevention of tourniquet-induced hypertension (TIH) and compared the effect of lidocaine to that of ketamine in patients undergoing general anesthesia.

Methods

This randomized, controlled, double-blind study included 75 patients who underwent lower limb surgery using a tourniquet. The patients were administered lidocaine (1.5 mg/kg, n = 25), ketamine (0.2 mg/kg, n = 25) or placebo (n = 25). The study drugs were administered intravenously 10 min before tourniquet inflation. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured before tourniquet inflation, after tourniquet inflation for 60 min at 10 min intervals, and immediately after tourniquet deflation. The incidence of TIH, defined as an increase of 30% or more in SBP or DBP during tourniquet inflation, was also recorded.

Results

SBP, DBP, and HR increased significantly over time in the control group compared to those in the lidocaine and ketamine groups for 60 min after tourniquet inflation (P < 0.001, P < 0.001, and P = 0.007, respectively). The incidence of TIH was significantly lower in the lidocaine (n = 4, 16%) and ketamine (n = 3, 12%) group than in the control group (n = 14, 56%) (P = 0.001).

Conclusion

Single-bolus lidocaine effectively attenuated blood pressure increase due to tourniquet inflation, with an effect comparable to that of bolus ketamine.

Transient Neurological Dysfunction and Intracranial Hypertension After Tourniquet Deflation in a Patient With a Head Injury: A Case Report

A tourniquet is used during surgery to produce a bloodless surgical field and decrease intraoperative blood loss. Although useful, tourniquets are associated with various physiological alterations both during inflation and deflation phases which may be poorly tolerated in compromised patients. We report a case of transient neurological dysfunction and intracranial hypertension after tourniquet deflation in a 15-year-old patient with a head injury. Intracranial hypertension under general anesthesia was diagnosed based on bradyarrhythmia and elevated ultrasonographic optic nerve sheath diameter as compared to preoperative values.

Effect of Tourniquet Use During Surgical Treatment of Open Fractures

BACKGROUND

We sought to evaluate whether tourniquet use, with the resultant ischemia and reperfusion, during surgical treatment of an open lower-extremity fracture was associated with an increased risk of complications.

METHODS

This is a retrospective cohort study of 1,351 patients who had an open lower-extremity fracture at or distal to the proximal aspect of the tibia and who participated in the FLOW (Fluid Lavage of Open Wounds) trial. The independent variable was intraoperative tourniquet use, and the primary outcome measures were adjudicated unplanned reoperation within 1 year of the injury and adjudicated nonoperative wound complications.

RESULTS

Unplanned reoperation and nonoperative wound complications were roughly even between the no-tourniquet (18.7% and 19.1%, respectively) and tourniquet groups (17.8% and 20.8%) (p = 0.78 and p = 0.52). Following matching, as determined by model interactions, tourniquet use was a significant predictor of unplanned reoperation in Gustilo Type-IIIA (odds ratio, 3.60; 95% confidence interval, 1.16 to 11.78) and IIIB fractures (odds ratio, 16.61; 95% confidence interval, 2.15 to 355.40).

CONCLUSIONS

The present study showed that tourniquet use did not influence the likelihood of complications following surgical treatment of an open lower-extremity fracture. However, in cases of severe open fractures, tourniquet use was associated with increased odds of unplanned reoperation; surgeons should be cautious with regard to tourniquet use in this setting.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

[Implementation of the wide awake local anesthesia no tourniquet (WALANT) type of anesthesia in hand surgery]

Wide awake local anesthesia no tourniquet (WALANT) refers to an anesthesia technique with low bleeding and complication rates, which enables interventions on the hand in an awake patient without the use of a tourniquet. Bleeding control is achieved through addition of vasoconstrictors to the infiltration solution. Since the motor function of the extremity is not affected, it offers the additional possibility of intraoperative active function testing. The WALANT procedure constitutes an established, effective, easily learnt and resource-sparing technique. The spectrum of surgical possibilities with WALANT is wide and covers nearly all elective and many emergency procedures. Due to multiple advantages in contrast to other regional and general anesthesia procedures, WALANT features an increasing spectrum of surgical applications and practitioners. It is therefore of interest for hand surgeons working both in hospitals and private practices.

Femoral artery block (FAB) attenuates thigh tourniquet-induced hypertension: a prospective randomized, double-blind, placebo-controlled trial

INTRODUCTION

Prolonged tourniquet inflation during surgery frequently leads to tourniquet hypertension (TH), which is thought to arise from compression of A-δ fibers leading to sympathetically mediated C fiber activation. In the lower extremity, C fibers and other sympathetic nerve fibers are carried along the femoral artery. We hypothesized that blockade of these fibers at the femoral artery would decrease the incidence of TH.

METHODS

Thirty American Society of Anesthesia 1-3 patients aged 18-75 undergoing total ankle arthroplasty were randomized to receive 15 mL of injectate (mepivacaine 1.5% or saline placebo) at the anteromedial aspect of the common femoral artery at the level of the inguinal crease under ultrasound guidance. Both groups received preoperative popliteal sciatic and saphenous nerve blocks for analgesia and a standardized general anesthetic. Esmolol was administered if systolic blood pressure rose >30% above baseline. Incidence of TH was the primary outcome.

RESULTS

TH was present in 93.3% of sham patients versus 33.3% of block patients. Mean systolic pressure at 120 min and 150 min of tourniquet time was significantly higher in the sham group compared with the block group. Esmolol requirement (95.3+107.6 v 8.0+14.2, p=<0.001) was also significantly higher in the sham group. No differences were noted in pain scores or opioid consumption, and no patient experienced sensory or motor block of the femoral nerve.

DISCUSSION

Under these experimental conditions, injection of local anesthetic around the femoral artery reduced the incidence of TH and intraoperative esmolol requirement.

TRIAL REGISTRATION NUMBER

www.clinicaltrials.gov (NCT03390426; December 28, 2017).

Impact of Dexmedetomidine on Tourniquet-Induced Systemic Effects in Total Knee Arthroplasty under Spinal Anesthesia: a Prospective Randomized, Double-Blinded Study

Background

Clinical studies on the impact of dexmedetomidine on tourniquet-induced systemic effects have been inconsistent. We investigated the impact of dexmedetomidine on tourniquet-induced systemic effects in total knee arthroplasty.

Methods

Eighty patients were randomly assigned to either control (CON) or dexmedetomidine (DEX) group. The DEX group received an intravenous loading dose of 0.5 μg/kg DEX over 10 minutes, followed by a continuous infusion of 0.5 μg/kg/h from 10 minutes before the start of surgery until completion. The CON group received the same calculated volume of normal saline. Pain outcomes and metabolic and coagulative changes after tourniquet application and after tourniquet release were investigated.

Results

The frequency of fentanyl administration postoperatively, patient-controlled analgesia (PCA) volume at 24 hours postoperatively, total PCA volume consumed in 48 hours postoperatively, and VAS score for pain at 24 and 48 hours postoperatively were significantly lower in the DEX group than in the CON group. Ten minutes after the tourniquet release, the DEX group showed significantly higher pH and lower lactate level than those in the CON group. Antithrombin III activity and body temperature 10 minutes after tourniquet release were significantly lower in the DEX group than in the CON group. Ca²⁺, K⁺, HCO₃ ^-, base excess, and PCO₂ levels 10 minutes after tourniquet release were not significantly different between the two groups.

Conclusion

We showed that DEX attenuated pain and hemodynamic, metabolic, and coagulative effects induced by the tourniquet. However, these metabolic and coagulative changes were within normal limits. Therefore, DEX could be used as an analgesic adjuvant, but should not be considered for routine use to prevent the systemic effects induced by tourniquet use.

AAAPT Diagnostic Criteria for Acute Knee Arthroplasty Pain

OBJECTIVE

The relationship between preexisting osteoarthritic pain and subsequent post-total knee arthroplasty (TKA) pain is not well defined. This knowledge gap makes diagnosis of post-TKA pain and development of management plans difficult and may impair future investigations on personalized care. Therefore, a set of diagnostic criteria for identification of acute post-TKA pain would inform standardized management and facilitate future research.

METHODS

The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership with the US Food and Drug Administration (FDA), the American Pain Society (APS), and the American Academy of Pain Medicine (AAPM) formed the ACTTION-APS-AAPM Pain Taxonomy (AAAPT) initiative to address this goal. A multidisciplinary work group of pain experts was invited to conceive diagnostic criteria and dimensions of acute post-TKA pain.

RESULTS

The working group used contemporary literature combined with expert opinion to generate a five-dimensional taxonomical structure based upon the AAAPT framework (i.e., core diagnostic criteria, common features, modulating factors, impact/functional consequences, and putative mechanisms) that characterizes acute post-TKA pain.

CONCLUSIONS

The diagnostic criteria created are proposed to define the nature of acute pain observed in patients following TKA.

Effects of Tourniquets in the Development of Pain States: a Novel Clinical Pilot Study and Review of Utilization of Tissue Oximetry to Measure Neural Ischemia

PURPOSE OF REVIEW

Approximately 20% of patients undergoing surgery develop persistent lower extremity pain following total knee arthroplasty. Animal studies have confirmed that prolonged tourniquet time increases the risk of endoneural ischemia and can mediate or modulate the development of chronic pain. The use of Near InfraRed Spectroscopy (NIRS) adjacent to nerve tissue, previously described as ONG has been shown to detect early neural compromise and has demonstrated clinical utility in carpal tunnel diagnosis.

RECENT FINDINGS

In this pilot study, we recruited 10 healthy adult volunteers to undergo oxyneurography (ONG) and sensory nerve conduction testing (sNCT). We performed testing on the upper and lower extremities in each individual. The tourniquet was applied followed by measurements of sNCT and ONG as described. We observed a significant drop in the mean ONG index at 3 and 5 min following tourniquet inflation in upper and lower extremities. Similar to raw ONG values, there was significant variability in sNCT measurements, which in general increased from baseline with tourniquet inflation. In the upper extremity, there was a significant increase in sNCT with tourniquet inflation, while in the lower extremity, there was a trend towards significance. The use of ONG can be supported as a diagnostic tool to detect nerve ischemia and to potentially reduce the incidence of tourniquet-mediated or -modulated neural ischemia and reduce the development of chronic post-tourniquet pain.

A randomized controlled trial of trigger finger release under digital anesthesia with (WALANT) and without adrenaline

BACKGROUND

Trigger finger release utilizing wide-awake local anesthesia no tourniquet (WALANT) usage in extremity surgery is not widely used in our setting due to the possibility of necrosis. Usage of a tourniquet is generally acceptable for providing surgical field hemostasis. We evaluate hemostasis score, surgical field visibility, onset and duration of anesthesia, pain score, and the duration of surgery and potential side effects of WALANT.

METHODS

Eighty-six patients scheduled for trigger finger release between July 2016 and December 2017 were randomized into a control group (1% lignocaine and 8.4% sodium bicarbonate with arm tourniquet; given 10 min prior to procedure) and an intervention group (1% lignocaine, 1:100,000 of adrenaline and 8.4% sodium bicarbonate; given 30 min prior to procedure), with a total of 4 ml of solution injected around the A1 pulley. The onset of anesthesia and pain score upon injection of the first 1 ml were recorded. After the procedure, the surgeon rated for the hemostasis score (1-10: 1 as no bleeding and 10 being profuse bleeding). Duration of surgery and return of sensation were recorded.

RESULTS

Hemostasis score was grouped into visibility score as 1-3: good, 4-6: moderate, and 7-10: poor. The intervention group (with adrenaline) had a 74% of good surgical field visibility compared to 44% from the controlled group (without adrenaline; p < 0.05). Duration of anesthesia was longer in the intervention group (with adrenaline), with a 2.77-h difference.

CONCLUSION

WALANT provides excellent surgical field visibility and is safe and on par with conventional methods but without the usage of a tourniquet and its associated discomfort.

Effect of remote ischaemic conditioning on coagulation function as measured by whole blood impedance aggregometry and rotational thromboelastometry in off-pump coronary artery bypass surgery: A randomised controlled trial

INTRODUCTION

Remote ischaemic conditioning (RIC) has been shown to prevent platelet activation during ablation for atrial fibrillation. RIC has also been associated with more postoperative transfusion in the off-pump coronary artery bypass graft surgery (OPCAB) patients. We evaluated the effects of RIC on coagulation function in OPCAB patients.

METHODS

A total of 58 patients undergoing OPCAB were randomised to the RIC or control group. In the RIC group, four cycles of 5 min of ischaemia and 5 min of reperfusion were applied twice to the upper arm after the induction of anaesthesia (preconditioning), and after the completion of coronary anastomoses (postconditioning). Whole blood impedance aggregometry (Multiplate®) and rotational thromboelastometry (ROTEM®) were performed before the induction of anaesthesia, at the end of surgery, and at postoperative day 1.

RESULTS

The trend towards a decrease in adenosine diphosphate-induced whole blood aggregation at the end of surgery was greater in the RIC group than in the control group, but this effect was not statistically significant (-10.4 [18.1] vs. -5.7 [24.8] U, P = 0.424). In ROTEM® analysis, the EXTEM area under the velocity curve was lower in the RIC group than in the control group at the end of surgery (3567 [1399-5794] vs. 5693 [4718-6179] mm∗100, respectively; P = 0.030). A tendency of larger perioperative blood loss was identified in the RIC group.

CONCLUSIONS

Although some parameters indicated a tendency for hypocoagulation in the RIC group at the end of surgery, most effects were not statistically significant. RIC does not significantly affect perioperative platelet aggregability and coagulation in patients undergoing OPCAB.

Tourniquet Use in Wide-Awake Carpal Tunnel Release

Background: Carpal tunnel syndrome is a common cause of upper extremity discomfort. Surgical release of the median nerve can be performed under general or local anesthetic, with or without a tourniquet. Wide-awake carpal tunnel release (CTR) (local anesthesia, no sedation) is gaining popularity. Tourniquet discomfort is a reported downside. This study reviews outcomes in wide-awake CTR and compares tourniquet versus no tourniquet use. Methods: Wide-awake, open CTRs performed from February 2013 to April 2016 were retrospectively reviewed. Patients were divided into 2 cohorts: with and without tourniquet. Demographics, comorbidities, tobacco use, operative time, estimated blood loss, complications and outcomes were compared. Results: A total of 304 CTRs were performed on 246 patients. The majority of patients were male (88.5%), and the mean age was 59.9 years. One hundred patients (32.9%) were diabetic, and 92 patients (30.2%) were taking antithrombotics. Seventy-five patients (24.7%) were smokers. A forearm tourniquet was used for 90 CTRs (29.6%). Mean operative time was 24.97 minutes with a tourniquet and 21.69 minutes without. Estimated blood loss was 3.16 mL with a tourniquet and 4.25 mL without. All other analyzed outcomes were not statistically significant. Conclusion: Operative time was statistically longer and estimated blood loss was statistically less with tourniquet use, but these findings are not clinically significant. This suggests that local anesthetic with epinephrine is a safe and effective alternative to tourniquet use in CTR. The overall rate of complications was low, and there were no major differences in postoperative outcomes between groups.

The effect of pregabalin on tourniquet-induced ischemia-reperfusion injury: a prospective randomized study

Background/aim

The aim of this study was to investigate the efficacy of pregabalin on ischemia-reperfusion injuries.

Materials and methods

Fifty-four patients were randomly assigned into 2 groups. A 150-mg tablet of pregabalin was given the night before and then 1 h before the operation for patients in Group P (pregabalin group, n = 27). A placebo was given to patients in Group C (control group, n = 27) at the same times. After combined spinal-epidural anesthesia was performed, venous blood samples were taken before tourniquet inflation (t₁), just before tourniquet deflation (t₂), and 20 min after tourniquet deflation (t₃) for the analysis of total antioxidant status (TAS), total oxidant status (TOS), catalase (CAT), and ischemia-modified albumin (IMA).

Results

There was no significant difference in TAS levels between the groups for the t₃ period. However, the TAS in Group P was significantly higher in the t₃ period than the t₂ period (mean ± SD, 0.46 ± 0.1 vs. 0.38 ± 0.2 mmol of Trolox equivalent/L, respectively; P < 0.05). The CAT level in the t₃ period was significantly higher in Group P than Group C (mean ± SD, 53.04 ± 32.1 vs. 35.46 ± 17.2 µmol/formaldehyde, respectively; P < 0.05). In the t₃ period, the TOS was significantly lower in Group P than Group C (mean ± SD, 11.97 ± 5 vs. 18.29 ± 9.9 pg/mL, respectively; P < 0.05). The TOS in Group P was significantly lower in the t₃ period than the t₂ period (mean ± SD, 11.97 ± 5 vs. 18.98 ± 10.7 pg/mL, respectively; P < 0.0001).

Conclusion

Pregabalin has no marked antioxidant activity, but it contributes to the antioxidant defense system of an organism.

Successful Treatment of Digital Ischemia Following a Carbon Dioxide Laser and Tourniquet for a Digital Procedure With Adjuvant Low-Level Laser Therapy

A digital tourniquet with/without epinephrine is commonly used in local anesthetics when operating on digits. However, such a complication as digital ischemia could occur following tourniquet application. We reported an elderly patient with atherosclerotic risk factors and she subsequently underwent a digital tourniquet, partial nail plate removal, and a carbon dioxide laser treatment for subungual wart with digital gangrene development. The successful treatment consisted of wound-dressing, medication, and adjuvant low-level light therapy (LLLT) to enhance the wound healing process, thereby resulting in almost complete recovery of skin color and function of the digit in 3 months. In conclusion, the digital tourniquet should be cautiously applied, especially in elderly patients with atherothrombosis, under minimal pressure and appropriate length of time. Moreover, LLLT could be an effective adjuvant treatment to prevent the vascular complications of the digit.

Reducing the Hypertensive Effects of the Prolonged Surgical Tourniquet Using a Dual-Cuff Strategy: A Prospective Randomized Controlled Trial

We evaluated whether moving the "line of crush" from thigh to the calf before onset of tourniquet-mediated hypertension would prevent or diminish it. We also evaluated any change in pain or functional outcome. Twenty adult patients were recruited and randomly assigned to either control or intervention groups. Inclusion criteria: any willing participant >18 years old with foot and/or ankle pathology requiring an operation lasting >90 minutes. Exclusion criteria included contraindication to general anesthesia, peripheral neuropathy affecting lower limbs of any etiology, or chronic pain requiring regular opiate analgesia. The intervention group received a thigh tourniquet for 60 minutes, after which a calf tourniquet was inflated and the thigh tourniquet was deflated. The control group received only a thigh tourniquet throughout surgery. At 90 minutes, the control group had mean arterial pressure of 86.8 mmHg, compared with the intervention group at 76.3 mmHg (p ≤ .014). At end of surgery, the difference had increased further (control 98.1 mmHg, intervention 78.3 mmHg (p ≤ .001). Moving the line of crush during limb tourniquet application prevents development of the hypertensive response. For cases in which a prolonged tourniquet application is required, a dual-tourniquet technique will prevent intraoperative hypertension and may influence long-term pain and function.

Minimising Tourniquet Time and Post-operative Pain During Carpal Tunnel Decompression

Background

Pain and discomfort at the tourniquet and wound site are recognised complications of carpal tunnel surgery. Studies have shown that longer tourniquet times lead to increased pain, local and systematic complications. We hypothesise that minimising the intraoperative tourniquet time will reduce post-operative pain and complications.

Objective

Our aim is to present the results of our novel operative technique for carpal tunnel decompression which minimises tourniquet time.

Method

The study represented a prospective case series in which 55 consecutive and unselected patients with positive nerve conduction study results were operated on by a single surgeon at a single hospital site over a period of 12 months. The patients filled in a questionnaire based on a visual analogue score (VAS) (1-10) for pain at (1) first presentation at the clinic, (2) recovery in theatre post-operatively and (3) on discharge from care at 12 weeks post-operatively. Questions included the perception of pain at the tourniquet site and at the wound site.

Results 

A total of 55 (female 39 and male 16) patients participated in the study. The average tourniquet time was 5 minutes 50 seconds. 98% of patients had a VAS of 1 at both the wound and tourniquet site post-operatively. One patent had a score of 3 at the tourniquet site. Eleven patients had undergone contralateral carpal tunnel decompression surgery. Of the remaining 43 patients, all said they would have the other side operated on in the same way.

Conclusion 

We have demonstrated a safe and efficient technique to reduce post-operative pain by minimising tourniquet inflation time. Our patient cohort experienced no significant complications and minimal pain post-operatively.