Free flap monitoring using an implantable Doppler probe

Abstract

Although clinical observation is the gold standard, the ideal free flap monitoring device has not been identified. The purpose of the present study was to review the first 14 months of experience using an implantable 20-MHz ultrasonic Doppler probe to monitor the microvascular anastamoses of free tissue transfers. Twenty-five flaps in 23 patients, with an average age of 51 years (age range 18 to 81 years), were performed. Probes were secured downstream of the venous anastamosis using a silicone-poly fluorotetraethylene sleeve. Doppler sounds were transduced before the flap was inset. Monitoring by nursing staff included conventional techniques (temperature, colour, capillary refill) and continuous Doppler flow monitoring. Dynamic diagnostic testing for anastomotic patency was facilitated by applying manual pressure on the flap to increase venous flow (the audible ‘whoosh’ sign) and valsalva manoeuvre to impede venous return momentarily (the ‘heave’ sign). Intraoperative vessel kinking, hematoma formation occluding venous outflow, and venous thrombosis were detected in four cases before concluding the procedure and corrected. Rapid, immediate cessation of audible flow was detected postoperatively in three of 25 flaps. Re-exploration (re-exploration rate 12%) led to salvage of all three flaps (salvage rate 100%). It was concluded from this study that flap re-exploration was prevented in four cases (16%) because of intraoperative use of the implantable Doppler probe. Earlier detection of flap compromise perioperatively is thought to have contributed to the 100% salvage rate and to the 100% flap survival rate in the first 25 cases in which the implantable Doppler probe was used.

Eight‐year experience of the Cook‐Swartz Doppler in free‐flap operations: Microsurgical and reexploration results with regard to a wide spectrum of surgeries

“…As previous studies have demonstrated, the implantable Doppler was found to be accurate, effective monitoring device, safe in use without related complications and detected a low false positive as maintained by Kind et al 8 and Rozen et al 9 Owing to its continual minute to minute feedback contrary to a clinical assessment, this monitoring instrument has since been integrated into the department routine in a quick and easy fashion. 8,22,37 In our study, the general results have shown a statistical significant in all three main parameters examined, with regard to the monitoring sort: higher success rates in the Doppler examined group ''D'' versus the control ''ND'' group (96.14% vs. 89.27%, P < 0.005), a decreased mean time of detecting a flap compromise in the implantable Doppler group, hence immediately rushing the patient to a reexploration surgery (1.333 days vs. 2.423 days, P < 0.01), and eventually an elevated successful flap salvage rates in microsurgical reexploration of the study's examined Doppler group (87.88% vs. 46.15%, P < 0.001; Table 1).…”

Doppler implantable dans la surveillance des lambeaux libres : une analyse coût-efficacité basée sur une revue systématique de la littérature

“…Dans la plupart des cas de faux positifs dénombrés dans les études les plus anciennes (jusqu'à 2006), ceuxci sont surtout dus à la courbe d'apprentissage associée à l'utilisation du dispositif, tels qu'un défaut de placement ou de fixation de la sonde, une mauvaise interprétation du signal ou un problème de batterie, ou encore un déplace-ment accidentel de la sonde par la pression exercée sur le fil de sortie [3,[22][23][24]. Dans une étude plus récente, Paydar et al [25] rapportent également que certains de leurs cas de faux positifs sont liés à l'apprentissage de l'utilisation de la nouvelle technologie.…”

“…Dans leur étude, ces auteurs n'ont toutefois expérimenté aucune de ces complications. French et al [22] et Schmulder et al [26] indiquent également n'avoir rencontré aucune complication liée à l'utilisation de la sonde Doppler implantable. Paydar et al [25] indiquent trois plicatures de la veine, pour deux patients sur 169, qui seraient liées au fil de la sonde Doppler.…”

“…Finalement, tel que mentionné par French et al [22], Pryor et al [27] et Schmulder et al [26], un autre important avantage du Doppler implantable en tant que méthode de surveillance directe par rapport à la surveillance clinique peut être observé pendant la période opératoire, en raison de la possibilité d'occurrence de tout type de problème (caillot sanguin et pression sur le pédicule vasculaire) à partir du moment où le Doppler implantable est connecté. Ces Tableau 2 Coûts associés à une chirurgie de transfert de tissu (en dollars canadiens).…”

Harvesting of forearm perforator flaps based on intraoperative vascular exploration: Clinical experiences and literature review

“…However, the use of these types of flaps is sometimes accompanied by some complications. In the attempt to drastically reduce flap complications and failure rate, the surgeons' efforts have been directed not only towards finding and developing new methods of postoperative surveillance of already performed flaps, 19,20 but also towards finding better ways to determine viable source arteries prior to the surgery. [21][22][23][24][25][26] The utility of these methods of detection has become obvious in the preoperative planning of perforator flaps.…”