Vasodilation by Verapamil-Nitroglycerin Solution in Microvascular Surgery

Objective Papaverine is a topical vasodilator commonly used during microvascular surgery to inhibit undesired vasoconstriction. A previous national shortage of papaverine prompted evaluation of an alternative, effective vasodilator. This study aims to assess the experience of a solution of verapamil and nitroglycerin (VG) as a potential alternative pharmacologic vasodilator. Study Design Retrospective case series. Setting Two tertiary academic medical centers. Subjects and Methods Among 298 patients, 306 consecutive free tissue transfers performed between 2014 and 2017 for head and neck defect reconstruction utilized a VG solution. Patient and flap characteristics, intraoperative patient and flap complications, and postoperative complications were reviewed. Diameter of the cervical recipient artery was measured intraoperatively before and after topical application of the VG solution in a subset of 43 patients (44 flaps). Results Flaps included fibula, radial forearm, subscapular system, and anterolateral thigh. In total, 3 (0.98%) flaps failed with varied etiology unrelated to the VG solution (venous thrombosis, arterial anastomosis thrombosis, physical damage to the perforator). Specific to topical application of the VG solution, the mean recipient artery diameter increased from 2.1 to 3.1 mm, a 48% increase ( P < .01). There were no intraoperative cardiac events or complications attributable to the VG solution. Conclusion We describe the use of a VG solution for pharmacologic vasodilation during microvascular free tissue transfer. Its use was associated with an acceptable incidence of adverse events, none of which were directly attributable to the VG solution. Apparent and sustained vasodilation was demonstrated. The VG solution represents a safe and efficacious alternative to papaverine in microvascular surgery.

Preserving the Blood Flow of the Recipient Artery in Cross-Leg Free Flap Procedure for Lower Extremity Reconstruction

When there is no suitable vessel in the injured leg for microsurgical transfer, cross-leg free flaps can be considered for lower extremity reconstruction. This report describes patients who experienced lower extremity trauma and underwent reconstruction with cross-leg free flaps with preserved blood flow in the recipient artery. Anterolateral thigh flap is preferred for small to moderate defects. The descending branch of the lateral femoral circumflex artery was dissected 2 cm proximally and distally and was prepared in a T-shape. The branches of the T were anastomosed to the recipient artery in the contralateral leg in the first session of the cross-leg free flap procedure. After 3 weeks, the flap artery was separated from the bifurcation. For large defects, the latissimus dorsi flap was chosen. The thoracodorsal artery was anastomosed to the contralateral posterior tibial artery in the first session. After 3 weeks, to provide recipient vessel integrity, the thoracodorsal artery was transected from the flap and anastomosed to the distal stump of the posterior tibial artery. Between January 2017 and January 2019, 8 defects were reconstructed using an anterolateral thigh flap; the remaining 4 defects were reconstructed using a latissimus dorsi flap. All flaps survived without complications. Anterograde flow distal to the anastomosis was confirmed in all recipient arteries via Doppler ultrasound. In cross-leg free flaps, the continuity of the recipient artery can be established to prevent diminished blood flow to the recipient extremity.

Technical Development of the Sutureless ELANA Clip Anastomosis Device

A cranial bypass can be a last resort procedure for patients suffering from complex neurovascular pathology. Since the clinically proven excimer laser-assisted nonocclusive anastomosis (ELANA) technique has become available, it is no longer necessary to temporarily close the recipient artery to facilitate an anastomosis. Aiming to simplify and shorten the operation time of the ELANA technique, a sutureless ELANA, the so-called SELANA slide (SEsl) was developed, but it failed during clinical study. We developed an improved device, the SELANA clip (SEcl).We describe the SEcl design and the first in vitro test results. The SEsl design was optimized with a clip at the backside, creating the SEcl which facilitates smooth and friction-free insertion in the recipient artery. Subsequently, the laser catheter was optimized by adding a grid and conus to provide an improved vacuum and flat reaction surface during lasing. We aimed to compare the SEcl to the current ELANA regarding application time difference, anastomosis success (“flap retrieval”) and technical difficulties. Hereto 32 ELANA and 32 SEcl anastomoses were performed on pressurized rabbit arteries in the ELANA practice system. Mean application time difference was 14.0 min (95%CI 13.0–15.0). The flap retrieval rate of the ELANA anastomoses was 94% (30/32) and 100% (32/32) for the SEcl technique. During the experiments no technical difficulties were encountered. The SEcl is technical feasible with promising simplicity and application times. However, extensive in vivo short-term and long-term experiments are indispensable before clinical application.

Is Precise Targeting of the Recipient Artery in a Superficial Temporal Artery–Middle Cerebral Artery Anastomosis Crucial?

Objective To investigate the difference in treatment outcomes according to the method used to select the recipient artery in superficial temporal artery–middle cerebral artery (STA-MCA) anastomoses. Methods We retrospectively analyzed the cases of 35 patients who underwent an STA-MCA anastomosis for internal carotid artery/MCA occlusion or stenosis. Patients were divided into two groups based on whether the recipient artery was precisely targeted by single-photon emission computed tomography (SPECT group) or less precisely targeted by visual assessment (Visual group). Then the bypass results in both groups were evaluated postoperatively based on changes in the regional cerebral blood flow (rCBF) and clinical outcomes. Results The delineated recipient artery in magnetic resonance angiography (MRA) matched the intraoperatively selected artery in 87.6% of the SPECT group cases and 83.3% of the Visual group cases. The SPECT group's digital subtraction angiography (DSA) findings coincided with the intraoperative selection in 76.9% of cases, and the MRA findings corresponded with the DSA findings in 92.3%. The postoperative areas with increased rCBF matched the perfused areas of intraoperatively selected arteries in 80.0% of the SPECT group cases and 77.8% of the Visual group cases. Postoperatively increased rCBF areas matching totally or partially with preoperative low-perfusion areas were observed in all cases. Conclusions The present results revealed no significant differences in the change in rCBF in the low-perfusion area between the patients whose recipient arteries were selected by SPECT or visual assessment.