Objectives: The pedicled intercostal muscle flap (IMF) is a high quality vascularized tissue commonly used to buttress the bronchial stump after pneumonectomy or bronchial anastomosis after sleeve lobectomy in order to prevent bronchopleural fistula formation. The evaluation of the viability of the muscle flap is difficult. The aim of this study was the assessment of the application of indicyanine green fluorescence for the evaluation of IMF perfusion.
Methods: The study included 27 patients (10 males and 17 females), mean age 62.6 years (47-77 years). Indocyanine green fluorescence (ICG) was used for objective assessment of the IMF quality by a near-infrared camera system (Photodynamic Eye(®), Hamamatsu Photonics, Japan). The following factors that may have an impact on the quality of the IMF were assessed: age, gender, body mass index, comorbidities, IMF length and thickness and timing of the harvesting during the procedure.
Results: The following surgical pulmonary resections with IMF harvesting were performed: 12 pneumonectomies, 2 sleeve lobectomies and 13 lobectomies. Intercostal muscle flap (IMF) was harvested before rib spreader insertion in 23 patients (85%) and at the end of the surgery in 4 patients (15%). The mean length and thickness of the harvested intercostal muscle were 19.9 ± 2.9 cm (range 13-24 cm) and 2.4 cm ± 0.7 cm (range 1.0-3.5 cm), respectively. Indocyanine green angiography showed ischaemia in the distal part of the muscle in all cases, despite the lack of obvious macroscopic signs. Median length of the ischaemic part was 4 cm (range 0.5-20 cm). The IMF length and thickness had a significant impact on the length of the ischaemic segment. In 24 patients, the ischaemic part of the muscle flap was severed. In 3 patients with the longest ischaemic segment (11, 13 and 20 cm), an alternative tissue was used to cover the bronchial stump. No major complications occurred.
Conclusions: Our preliminary results confirmed the simplicity and high efficacy of ICG in the assessment of intercostal muscle blood perfusion. ICG was superior to macroscopic evaluation and influenced surgical proceeding.
Keywords: Bronchopleural fistula; Indocyanine green fluorescence; Intercostal muscle flap.