Le micro-doppler implantable dans la surveillance des lambeaux microanastomosés en chirurgie reconstructrice cervico-faciale

The Use of the Implantable Doppler Probe as a Blood Flow Monitoring Device in Clinical Settings: A Narrative Review of the Evidence

OBJECTIVES

In the past decade, the implantable Doppler probe has been studied widely as a blood flow-monitoring device in reconstructive and transplant surgical specialities. Its utility as an effective postoperative monitoring technique is still debatable, with no clear guidelines in clinical practice. Here, we mapped the current evidence on the usefulness of the implantable Doppler probe as a blood flow-monitoring device. The objective was to present an up-to-date assessment of the benefits and limitations of using implantable Doppler probes in clinical and experimental clinical settings.

MATERIALS AND METHODS

We conducted a literature search using the Cochrane Library and Healthcare Databases Advanced Search and using implantable Doppler probe, transplant, graft, and flap as key words. The search yielded 184 studies, with 73 studies included after exclusions. We evaluated, synthesized, and summarized the evidence from the studies in tabular form.

RESULTS

There is clinical equipoise regarding the effectiveness of implantable Doppler probe as a flow sensing technique. The main reason is the lack of information and gaps in the evidence regarding the benefits and limitations of using implantable Doppler probes in clinical practice.

CONCLUSIONS

The implantable Doppler probe has the potentialto be used as an adjunctpostoperativeblood flow-monitoring device. However, keeping in view of technical limitations, its signals should be interpreted alongside traditional clinical assessment techniques to determine the patency of microvascular anastomosis. Although evidence in this review will inform clinical practice in transplant and reconstructive surgical specialties, a prospective randomized controlled study with a larger patient cohort is required to evaluate the effectiveness of this probe in clinical settings.

Fluorescent indocyanine green angiography: Preliminary results in microsurgery monitoring

INTRODUCTION

Pedicled flaps and free-tissue transfer flaps are used routinely to reconstruct hard and soft tissue defects in head and neck, limb, hand, thoracic and abdominopelvic reconstructive surgery. But failure remains a constant concern, particularly in free-tissue transfers. Usually failure is due to blood supply compromise. Indocyanine green (ICG), a fluorescent dye is a suitable tracer for vessel perfusion. The objective of this study is to evaluate the fluorescent indocyanine green angiography (FA ICG) in free flaps procedures.

MATERIEL AND METHODS

Patients who had microsurgical flap reconstruction were included during the study period in a single center. The FA ICG was used at specific times. Intra-veinous injections of 0.1mg/kg of INFRACYANINE^® (concentration 2.5mg/mL) were done intraoperatively. The Fluobeam^® device programmed on sensitivity and mapping to interpret the data, was used. These different injections allowed to checked skin paddle perforators vessels, osseous perforators vessels, arterial and venous patency after anastomosis and the cutaneous, muscular and osseous perfusion.

RESULTS

A total of 12 patients enrolled were 10 males and 1 female. Their mean age was 54.5 years (range 25-75 years). Of the 12 flaps, 8 were free flaps with 4 fibular flaps (3 for mandibular reconstruction and one for femur reconstruction); 2 radial forearm flaps for maxillary reconstruction; one latissimus free flap for tibia skin coverage and one retroauricular fasciocutaneous free flap for thumb skin coverage. We got to modify specific steps during surgery with 8 patients by using the FA ICG to anticipate potential complications: modifying the draw of the skin paddle, recut of this paddle, modifying the osteotomies, re-doing the anastomosis or modifying the position of the pivot point.

DISCUSSION

Evaluation of microvascular flap perfusion is still based on subjective clinical features. Clinical monitoring is observer-dependent and does not allow information sharing, test reproducibility, and consistent postoperative follow-up. The successful of salvage rate is linked to the delay between the onset of ischemia and its clinical assessment. FA ICG could be a reliable method for monitoring free-tissue transfers. This technique is objective, non invasive and facilitate a complex reconstructive procedure to augment is liability. This technique may be used such a pedagogical tool for young practitioners in their first microsurgery procedures.

Indocyanine green fluorescence angiography for free flap monitoring: A pilot study

OBJECTIVE

We evaluated the feasibility and the tolerance of repeated fluorescent indocyanine green angiography in free flap monitoring, and determined the intraoperative predictive values of flap vitality.

BACKGROUND

The free flap failure rate has been significantly reduced, but free flap loss still occurs and remains a costly disaster. Repeated clinical examinations are commonly used for flap monitoring, but they can be unreliable because of their subjectivity. Laser-induced fluorescence of indocyanine green is a new method for assessing tissue perfusion.

METHODS

20 patients undergoing microsurgical reconstruction were monitored by indocyanine green fluorescence angiography, intraoperatively, and during 4 days after surgery, with 18 injections. Monitoring was made by clinical examination, and then compared to angiographic findings.

RESULTS

The vascular complication rate was 15% (3/20) with 2 cases of venous thrombosis and one case of partial necrosis of the flap skin paddle. Both cases of venous thrombosis were salvaged by secondary surgery. There was no total flap loss. ICG angiography allowed detecting each intra and postoperative complication, earlier than clinical examination. The mean per-operative intensity of fluorescence was significantly lower in flaps with vascular complications (23.8 GL/ms; p = 0.008). The postoperative slope (p = 0.02) and amplitude (p = 0.03) of the fluorescent signal were both significantly lower than for uncomplicated flaps, before surgical revision. These 2 parameters came back to normal values after secondary surgery. There was no adverse effect of ICG despite the repeated injections.

CONCLUSION

ICG angiography is a feasible and safe technique for the detection of free flap vascular complications.

[Free radial forearm flap in head and neck: our experience]

INTRODUCTION

Oncologic surgery leads to important defects and sequelae, as well as notable cosmetic and functional alterations. In this aspect reconstructive surgery has an essential role, allowing more radical excision and lower associated functional and cosmetic morbidities. The aim of this study was to present and evaluate the experience and results of the reconstructive microsurgery unit in our centre's ENT department.

METHODS

Retrospective study of procedures performed between 2006 and 2012.

RESULTS

A total of 36 cases were reviewed. The primary tumour was found in the oropharynx (58%) in the majority of cases. In 5 cases the procedure was performed for reconstruction and fistula closure (4 pharyngostoma and 1 tracheoesophageal fistula). Failure from total necrosis was 16% (6/36). No associated mortality has been reported. The most common postoperative complications were wound dehiscence in 5 patients and pharyngostoma (fistula) in 5 cases. Prior radiotherapy significantly influenced the increase in the overall incidence of complications (P<05).

CONCLUSIONS

Reconstructive surgery currently plays an important role in surgery for head and neck cancer. The radial forearm flap is a safe, reliable method for reconstruction of most defects in the ENT field. This type of intervention provides greater autonomy and safety in surgical oncology.