Effects of prolonged ischemia on human skeletal muscle microcirculation as assessed by near-infrared spectroscopy

Abstract

Near-infrared spectroscopy (NIRS) has been used to detect in vivo microvascular alterations by means of a vascular occlusion test. We sought to analyse by NIRS the microcirculatory profile of patients undergoing prolonged tourniquet-induced bloodless condition for extremity surgery, and compare the results with time of ischemia and comorbidities. We conducted a prospective observational study on 42 patients undergoing upper limb surgery. Regional anaesthesia was achieved and ischemia was induced by a tourniquet cuffed at 250 mmHg. The probe of a NIRS monitor (InSpectra 325, Hutchiston, USA) was placed on the brachial muscle, and muscle oxygen saturation (StO 2 ) was recorded continuously before anaesthesia, during and after surgery. The following variables were recorded: baseline StO 2 , StO 2 desaturation slope during occlusion (dSlope, units/s), resaturation rate following ischemia (RR, units/s), hyperaemic peak (peak, units), and duration of the hyperaemic period following ischemia (hyperaemic time, s). Values of dSlope were similar among all patients. RR and hyperaemic time were significantly correlated with the duration of ischemia, but not with comorbidities [p = 0.007 CI (-35.64 to -13.1), and p \ 0.001 CI (0.049-0.159), respectively]. Grouping patients by duration of ischemia (30, 60, or 90 min), we found a significant decrease in RR after 60 and 90 min (p \ 0.001 and p = 0.03, respectively). Hyperaemic peak was lower in the 90 min group (83.9 ± 6.8 vs.91.2 ± 5.7 %, p = 0.02) whereas the hyperaemic time was significantly increased (595 ± 136 vs. 429 ± 107 min, p \ 0.001). Alterations of skeletal muscle microcirculation were correlated with the duration of ischemia, but not with comorbidities. We observed an initial impairment of the microcirculatory recovery at 90 min of ischemia.

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

“…These results indicate that the duration of ischemia has an influence on a possible hyperemic response. Tujjar et al showed that the hyperemic peak of the treated upper extremity measured using NIRI was also lower in patients with a longer duration of ischemia [ 26 ]. Reactive hyperemia in healthy volunteers was shown as a significant increase in the regional oxygen saturation above the initial values after release of an upper arm tourniquet ischemia [ 27 ].…”

“…In contrast to others [ 26 ], we evaluated the influence of the tourniquet ischemia under local anesthesia to avoid the possible influence of plexus anesthesia on tissue oxygen saturation. As already described, the use of plexus anesthesia or the perioperative placement of a plexus catheter leads to an increase in local blood flow to the ipsilateral upper extremity and to vasodilatation [ 37 , 38 , 39 ].…”

Comparison of the Effects of Inhalation and Spinal Anesthesia on Microcirculation in Transverse Rectus Abdominis and Gluteus Maximus Muscle-Skin Flap Applications in Experimental Rat Models

“…General anesthesia offers certain advantages, such as airway integrity, maintenance of ventilation in accordance with physiological conditions, sensitive control of anesthetic agent concentration through monitorization, the opportunity to make rapid changes to anesthetic levels, and rapid awakening (Corcoran et al, 2006). That said, the technique also comes with certain disadvantages, including postoperative symptoms such as nausea-vomiting, while in cases receiving inhalation anesthesia, blood flow can be reduced in the flap, negatively affecting flap viability (Ederer et al, 2020;Seal et al, 2011;Tujjar et al, 2017;Lee at al., 2020), and postoperative pain can lead to vasospasm (Lanz et al, 2001;Banic et al, 1997). For such reasons, flap perfusion may be adversely affected (Adolphs et al, 2004).…”

Journal of Clinical Monitoring and Computing 2017/2018 end of year summary: monitoring—and provocation—of the microcirculation and tissue oxygenation

“…In another study by Tujjar in the June 2017 issue of this journal [10], the evolution of StO 2 following a rather extensive “VOT” was analyzed. First, for patients who underwent extremity surgery, regional anesthesia was provided, which was associated with a rise in StO 2 .…”