Intramuscular Near-Infrared Spectroscopy for Muscle Flap Monitoring in a Porcine Model
Research article published in Journal of reconstructive microsurgery (2021)
Abstract
BACKGROUND: Current near-infrared spectroscopy (NIRS)-based systems for continuous flap monitoring are limited to flaps which carry a cutaneous paddle. As such, this useful and reliable technology has not previously been applicable to muscle-only free flaps where other modalities with substantial limitations continue to be utilized. METHODS: We present the first NIRS probe which allows continuous monitoring of local tissue oxygen saturation (StO2) directly within the substance of muscle tissue. This probe is flexible, subcentimeter in scale, waterproof, biocompatible, and is fitted with resorbable barbs which facilitate temporary autostabilization followed by easy atraumatic removal. This novel device was compared with a ViOptix T.Ox monitor in a porcine rectus abdominus myocutaneous flap model of arterial and venous occlusions. During these experiments, the T.Ox device was affixed to the skin paddle, while the novel probe was within the muscle component of the same flap. RESULTS: The intramuscular NIRS device and skin-mounted ViOptix T.Ox devices produced very similar StO2 tracings throughout the vascular clamping events, with obvious and parallel changes occurring upon vascular clamping and release. The normalized cross-correlation at zero lag describing correspondence between the novel intramuscular NIRS and T.Ox devices was >0.99. CONCLUSION: This novel intramuscular NIRS probe offers continuous monitoring of oxygen saturation within muscle flaps. This experiment demonstrates the potential suitability of this intramuscular NIRS probe for the task of muscle-only free flap monitoring, where NIRS has not previously been applicable. Testing in the clinical environment is necessary to assess durability and reliability.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Current near-infrared spectroscopy (NIRS)-based systems for continuous flap monitoring are limited to flaps which carry a cutaneous paddle.
Why This Matters for Hirudotherapy
This study describes a novel intramuscular near-infrared spectroscopy (NIRS) probe for continuous monitoring of tissue oxygen saturation within muscle flaps, tested in a porcine rectus abdominus myocutaneous flap model involving arterial and venous occlusion. The probe demonstrated high cross-correlation with a commercially available skin-mounted NIRS device during vascular clamping events. The abstract makes no mention of leeches, hirudin, hirudotherapy, or any leech-derived products, and the study addresses surgical monitoring technology and flap physiology. There is no defensible leech-relevance link for this article within ASH's domain.
Citation
Intramuscular Near-Infrared Spectroscopy for Muscle Flap Monitoring in a Porcine Model
Bai W et al. · Journal of reconstructive microsurgery, 2021
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