A study of the blood flow restriction pressure of a tourniquet system to facilitate development of a system that can prevent musculoskeletal complications

Authors

  • Hiroyuki Maeda, MD, PhD
  • Hideaki Iwase, PhD
  • Akio Kanda, MD, PhD
  • Itaru Morohashi, MD, PhD
  • Kazuo Kaneko, MD, PhD
  • Mutsuhiro Maeda
  • Yuki Kakinuma
  • Yusuke Takei
  • Shota Amemiya
  • Kazuyuki Mitsui, PhD

DOI:

https://doi.org/10.5055/ajdm.2017.0267

Keywords:

tourniquet, motor complication, electrohydrodynamics

Abstract

Background: After an emergency or disaster, subsequent trauma can cause severe bleeding and this can often prove fatal, so promptly stopping that bleeding is crucial to preventing avoidable trauma deaths. A tourniquet is often used to restrict blood flow to an extremity. In operation and hospital, the tourniquet systems currently in use are pneumatically actuated by an air compressor, so they must have a steady power supply. These devices have several drawbacks: they vibrate and are noisy since they are pneumatically actuated and they are far from portable since they are large and heavy.

Introduction: Presumably, the drawbacks of pneumatic tourniquets could be overcome by developing a small, lightweight, vibration-free, quiet, and battery- powered tourniquet system. The current study built a small, vibration-free electrohydrodynamic (EHD) pump and then used that pump to restrict blood flow to the leg of rats in an experiment. This study explored the optimal conditions for effective restriction of blood flow by assessing biochemical and musculoskeletal complications following the restriction of blood flow, and this study also examined whether or not an EHD pump could be used to actuate a tourniquet system.

Methods: A tourniquet cuff (width 12 mm × length 150 mm, material: polyolefin) was placed on the thigh of Wistar rats and pressure was applied for 2 hours by a device that uses EHD phenomena to generate pressure (an EHD pump). Animals were divided into four groups based on how much compressive pressure was applied with a tourniquet: 40 kPa (300 mm Hg, n = 13),  30 kPa (225 mm Hg, n = 12), 20 kPa (150 mm Hg, n = 15), or 0 kPa (controls, n = 25). Tissue oxygen saturation (regional oxygen saturation, denoted here as rSO2) was measured to assess the restriction of blood flow. To assess behavior once blood flow resumed, animal activity was monitored for third day and the amount of movement was counted with digital counters. Body weight was measured before and after the behavioral experiment, and changes in body weight were determined. Blood was sampled after a behavioral experiment and biochemically assessed and creatine kinase (CK) levels were measured.

Results: Tissue oxygen saturation decreased significantly in each group. When a tourniquet was applied at a pressure of 30 kPa or more, tissue oxygen saturation decreased significantly. The amount of movement (the count) over third day decreased more when a tourniquet was applied at a higher pressure. The control group resumed the same amount of movement per day second after blood flow resumed. Animals to which a tourniquet was applied at a pressure of 20 or 30 kPa resumed the same amount of movement third day after blood flow resumed. In contrast, animals to which a tourniquet was applied at a pressure of 40 kPa did not resume the same amount of movement third day after blood flow resumed. After the behavioral experiment, animals to which a tourniquet was applied at a pressure of 40 kPa had a significantly lower body weight in comparison to the control group. After the behavioral experiment, animals to which a tourniquet was applied at a pressure of 40 kPa had significantly elevated CK levels in comparison to the control group.

Discussion and Conclusion: A relationship between blood flow restriction pressure and tissue oxygen saturation was noted. rSO2 measurement can be used to assess the restriction of blood flow during surgery. On the basis of the decrease in rSO2, blood flow was effectively restricted at a pressure of 30 kPa or more. When, however, blood flow was restricted at a pressure of 40 kPa, weight loss and decreased movement were noted and CK levels increased after the behavioral experiment. Thus, complications had presumably developed due to damage to muscle tissue. These findings indicate that blood flow was effectively restricted in this experiment and they also indicate the existence of an optimal blood flow restriction pressure that does not cause musculoskeletal complications. The pressure in question was around 30 kPa. The tourniquet system that was developed here is actuated with an EHD pump that is still in the trial stages. That said, its pressure can readily be controlled and this pump could be used in a tourniquet system since it is quiet, vibration-free, and small. The pressure of this pump can be finely adjusted to prevent musculoskeletal complications.

Author Biographies

Hiroyuki Maeda, MD, PhD

Department of Orthopaedic Surgery, School of Medicine, Juntendo University, Tokyo, Japan

Hideaki Iwase, PhD

Department of Orthopaedic Surgery, Shizuoka Medical Research Center for Disaster School of Medicine, Juntendo University, Shizuoka, Japan

Akio Kanda, MD, PhD

Department of Orthopaedic Surgery, Shizuoka Medical Research Center for Disaster, School of Medicine, Juntendo University, Shizuoka, Japan

Itaru Morohashi, MD, PhD

Department of Orthopaedic Surgery, Shizuoka Medical Research Center for Disaster, School of Medicine, Juntendo University, Shizuoka, Japan

Kazuo Kaneko, MD, PhD

Department of Orthopaedic Surgery, School of Medicine, Juntendo University, Tokyo, Japan

Mutsuhiro Maeda

Yamamoto and Maeda Memorial Maeda Hospital, City of Higashikurume, Tokyo, Japan

Yuki Kakinuma

Department of Mechanical Engineering, School of Engineering, Tokyo Denki University, Tokyo, Japan

Yusuke Takei

Department of Mechanical Engineering, School of Engineering, Tokyo Denki University, Tokyo, Japan

Shota Amemiya

Department of Mechanical Engineering, School of Engineering, Tokyo Denki University, Tokyo, Japan

Kazuyuki Mitsui, PhD

Department of Mechanical Engineering, School of Engineering, Tokyo Denki University, Tokyo, Japan

References

Jean P, Joanna M, Philippe R: The pneumatic tourniquet: Mechanical, ischaemia-reperfusion and systemic effects. Eur J Anaesthesiol. 2011; 28.

Estebe JP, Le Naoures A, Chemaly L, et al: Tourniquet pain in a volunteer study: Effect of changes in cuff width and pressure. Anaesthesia. 2000; 55: 21-26.

Wakai A, Winter DC, Street JT, et al. Pneumatic tourniquet in extremity surgery. J Am Acad Orthop Surg. 2001; 9: 345-351.

Saied A, Ayatollahi Mousavi A, Arabnejad F, et al.: Tourniquet in surgery of the limbs: A review of history, types and complications. Iran Red Crescent Med J. 2015; Feb 18, 17(2): e9588.

Sakai N, Inoue T, Kunugiza Y, et al.: Continuous femoral versus epidural block for attainment of 120 ° knee flexion after total knee arthroplasty: a randomized controlled trial. J Arthroplasty. 2013 May; 28(5): 807-814.

Parmet JL, Horrow JC, Berman AT, et al.: The incidence of large venous emboli during total knee arthroplasty without pneumatic tourniquet use. Anesth Analg. 1998 Aug; 87(2): 439-444.

Kato N, Nakanishi K, Yoshino S, et al.: Abnormal echogenic findings detected by transesophageal echocardiography and cardiorespiratory impairment during total knee arthroplasty with tourniquet. Anesthesiology. 2002 Nov; 97(5): 1123-1128.

The Association of peri Operative Registered Nurses: Recommended practices for use of the pneumatic tourniquet. In: Perioperative Standards and Recommended Practices. 2009 ed. Denver, CO: AORN Inc, 2009; 249: 1-7.

Olivecrona C, Ponzer S, Hamberg P, et al.: Lower tourniquet cuff pressure reduces postoperative wound complications after total knee arthroplasty: A randomized controlled study of 164 patients. J Bone Joint Surg Am. 2012 Dec 19; 94(24): 2216-2221.

Yalcınkaya M, Sokucu S, Erdog˘an S, et al.: Tourniquet use in orthopedic surgery: A descriptive survey study among Turkish orthopedic surgeons and residents in Istanbul. Acta Orthop Traumatol Turc. 2014; 48(5): 483-490.

Published

07/01/2017

How to Cite

Maeda, MD, PhD, H., H. Iwase, PhD, A. Kanda, MD, PhD, I. Morohashi, MD, PhD, K. Kaneko, MD, PhD, M. Maeda, Y. Kakinuma, Y. Takei, S. Amemiya, and K. Mitsui, PhD. “A Study of the Blood Flow Restriction Pressure of a Tourniquet System to Facilitate Development of a System That Can Prevent Musculoskeletal Complications”. American Journal of Disaster Medicine, vol. 12, no. 3, July 2017, pp. 139-45, doi:10.5055/ajdm.2017.0267.

Issue

Section

Articles