Real time measurement of intramuscular pH during routine knee arthroscopy using a tourniquet

Abstract

Aims Tourniquets have potential adverse effects including postoperative thigh pain, likely caused by their ischaemic and possible compressive effects. The aims of this preliminary study were to determine if it is possible to directly measure intramuscular pH in human subjects over time, and to measure the intramuscular pH changes resulting from tourniquet ischaemia in patients undergoing knee arthroscopy. Methods For patients undergoing short knee arthroscopic procedures, a sterile calibrated pH probe was inserted into the anterior fascial compartment of the leg after skin preparation, but before tourniquet inflation. The limb was elevated for three minutes prior to tourniquet inflation to 250 mmHg or 300 mmHg. Intramuscular pH was recorded at one-second intervals throughout the procedure and for 20 minutes following tourniquet deflation. Probe-related adverse events were recorded. Results A total of 27 patients were recruited to the study. Mean tourniquet time was 21 minutes (10 to 56). Tourniquet pressure was 300 mmHg for 21 patients and 250 mmHg for six patients. Mean muscle pH prior to tourniquet inflation was 6.80. Muscle pH decreased upon tourniquet inflation, with a steeper fall in the first ten minutes than for the rest of the procedure. Change in muscle pH was significant after five minutes of tourniquet ischaemia (p < 0.001). Mean muscle pH prior to tourniquet release was 6.58 and recovered to 6.75 within 20 minutes following release. No probe related adverse events were recorded. Conclusion It is possible to directly measure skeletal muscle pH in human subjects over time. Tourniquet ischaemia results in a decrease in human skeletal muscle pH over time during short procedures. Cite this article: Bone Joint Res 2021;10(6):363–369.

The Donnan-dominated resting state of skeletal muscle fibers contributes to resilience and longevity in dystrophic fibers

“…Fig. 6 could mimic application of tourniquets ( MacDonald et al, 2021 ) and compartment syndrome ( Tatman et al, 2020 ). Depending on the severity of vascular constriction in compartment syndrome, ischemic and anoxic fibers’ rundown to firing threshold would vary enormously, consistent with reports, in compartment syndrome, of the unpredictable timing of lethal threshold events ( Johnstone and Ball, 2019 ).…”

Is Tourniquet Pain the Result of Increased Compartment Pressure in the Forearm?

“…The mechanisms of tourniquet pain are not understood, and therefore, the treatment is nonspecific. 11,12 Some of the complications of the pneumatic tourniquet used during upper limb surgery result from excessive direct pressure placed upon the vital structures of the limb. Most surgeons choose a tourniquet pressure approximately 100 mm Hg above the systolic pressure of the patient.…”

“…Tourniquet pain frequently complicates the use of pneumatic tourniquets during surgical procedures involving the extremities. The mechanisms of tourniquet pain are not understood, and therefore, the treatment is nonspecific 11,12 …”

The use of tourniquet is useful in terms of blood loss and soft tissue damage in arthroscopic anterior cruciate ligament reconstruction: a retrospective study

“…The tourniquet is widely used and useful for securing the surgical field during arthroscopic anterior cruciate ligament reconstruction (ACLR) 1 . Since the tourniquet is applied to the proximal thigh and tightened to obstruct blood flow to the affected leg, concerns have been raised regarding the potential for muscle damage at the site of direct pressure and the effects of blood stagnation and ischemia in the entire lower extremity 2 , 3 . In fact, perioperative complications have been reported with the use of tourniquet, including an increased incidence of postoperative deep venous thrombosis (DVT) 4 – 6 , quadriceps muscle weakness 7 , increased pain 8 , and nerve damage 9 , 10 .…”