Implantable Doppler Removal After Free Flap Monitoring Among Head and Neck Microvascular Surgeons

Flap blood glucose measurement for flap monitoring and early detection of circulatory problems

Postoperative monitoring of skin flaps is subjective and cannot detect early circulatory problems in the flap. Early detection and rapid remedial re-exploration are important for flap salvage. We evaluated flap glucose measurement to monitor the flaps for early detection of circulatory problems. In total, 30 patients underwent cutaneous flap reconstruction. This is an easy, economic, objective, and reliable method for flap monitoring and can detect early venous congestion requiring remedial measures.

Mandibular reconstruction using an iliac bone flap with perforator-supported external oblique abdominal muscle island: a pilot study

The deep circumflex iliac artery (DCIA) flap is one of the bone flaps commonly used for mandibular reconstruction. Observation of the skin paddle and Doppler ultrasound are methods that are usually used to monitor DCIA flaps after mandibular reconstruction surgery. The aim of this study was to introduce a novel DCIA flap with a perforator-supported external oblique abdominal muscle (EOAM) island for postoperative flap monitoring. This study included five patients who underwent mandibular reconstruction using this modified technique. The DCIA flap and the EOAM island supplied by the ascending branch of the DCIA were harvested during the surgery. After mandibular reconstruction, the EOAM island was placed in the submandibular region to monitor the blood supply to the DCIA flap after surgery. The blood supply to the DCIA flap was monitored by observing the colour, texture, and bleeding condition of the EOAM island. After the monitoring period, the EOAM was removed and the ascending branch of the DCIA was ligated. The outcome was successful in all patients. The EOAM island supported by the ascending branch of the DCIA is reliable and safe, thus providing a robust option to monitor the blood supply to the DCIA flap.

Complications related to the Cook-Swartz implantable Doppler probe use in head and neck microvascular reconstruction: a systematic review

PURPOSE

Vascular perfusion research has been dedicated to identify inexpensive, effective, and easy to use methods to assess free flap perfusion for both buried and non-buried flaps.

METHODS

Systematic review of complications in patients underwent Head and Neck microsurgical reconstruction and vascular implantable Doppler monitoring.

RESULTS

Sixteen articles were included for qualitative analysis. 2535 (92.2%) patients received IDP monitorization. Venous thrombosis was the most common vascular complication effecting 28 (1.1%). Regarding complications potentially related to the use of the IDP, just one study described the presence of granuloma formation along the suture line in 2 (0.07%) patients.

CONCLUSIONS

Our findings indicated that Cook-Swartz IDP will represents a safe and effective device for FF monitoring in HN reconstructive micro-surgery. A detailed prospective registration of the results and complications related to the use of IDP remains mandatory to precisely estimate results, cost, and complications.

Free flaps monitoring by Laser-Doppler Flowmetry in head and neck surgery

Objective

Early recognition of free flap vascular impairment is essential for flap salvage attempts. Several methods for surveillance of post-operative flaps are available. Among these, we have extensively used Laser-Doppler Perfusion Flowmetry (LDF) monitoring. We report our experience on this topic and illustrate the advantages and weak points.

Methods

Over seven years, 110 consecutive free flaps for head and neck reconstruction were monitored using the Periflux System 5000^® (Perimed AB, Järfälla, Sweden). In addition to maximum and minimum peaks, a pattern called vasomotion can be detected. Monitoring time lasted from 3 to 7 days, 24/24 h.

Results

Six of 110 (5.5%) cases of vascular problems were detected and clinically confirmed. In 5 cases, venous thrombosis was present: 4 patients were successfully treated. In 1 case, both arterial and venous thrombosis occurred. Flowmetry data always showed a more or less sudden disappearance of vasomotion.

Conclusions

LDF is a highly sensible, specific and reliable method. It is easy to use and interpret at low cost. Remote monitoring could also be developed.

Comparison of Hyperspectral Imaging and Microvascular Doppler for Perfusion Monitoring of Free Flaps in an In Vivo Rodent Model

To reduce microvascular free flap failure (MFF), monitoring is crucial for the early detection of malperfusion and allows timely salvage. Therefore, the aim of this study was to evaluate hyperspectral imaging (HSI) in comparison to micro-Doppler sonography (MDS) to monitor MFF perfusion in an in vivo rodent model. Bilateral groin flaps were raised on 20 Sprague−Dawley rats. The femoral artery was transected on the trial side and re-anastomosed. Flaps and anastomoses were assessed before, during, and after the period of ischemia every ten minutes for overall 60 min using HSI and MDS. The contralateral sides’ flaps served as controls. Tissue-oxygenation saturation (StO2), near-infrared perfusion index (NPI), hemoglobin (THI), and water distribution (TWI) were assessed by HSI, while blood flow was assessed by MDS. HSI correlates with the MDS signal in the case of sufficient and completely interrupted perfusion. HSI was able to validly and reproducibly detect tissue perfusion status using StO2 and NPI. After 40 min, flap perfusion decreased due to the general aggravation of hemodynamic circulatory situation, which resulted in a significant drop of StO2 (p < 0.005) and NPI (p < 0.005), whereas the Doppler signal remained unchanged. In accordance, HSI might be suitable to detect MFF general complications in an early stage and further decrease MFF failure rates, whereas MDS may only be used for direct complications at the anastomose site.