Intraosseous microdialysis for bone free flap monitoring in head and neck reconstructive surgery: A prospective pilot study.

Stéphanie Dakpé,Emilien Colin,Momar Diouf,Bernard Devauchelle,Julien Davrou,Sylvie Testelin,Jérémie Bettoni

doi:10.1002/micr.30529

Abstract

BackgroundAlthough some researchers have positioned microdialysis catheters in the soft tissue surrounding bone, the results did not accurately reflect bone metabolism. The present study's objective was to establish the feasibility of microdialysis with a catheter positioned directly in bone.MethodsThirty‐four patients (19 males, 15 females; median age: 59) were included in a prospective, nonrandomized clinical trial in the Department of Maxillofacial Surgery at Amiens‐Picardie University Hospital (Amiens, France). Fibula or iliac crest free flaps were used in reconstructive head and neck surgery (for cancer, osteoradionecrosis, trauma, or ameloblastoma) and monitored with microdialysis catheters positioned in a hole drilled into the bone. Glucose, lactate, pyruvate, and glycerol concentrations were analyzed for 5 days.ResultsAll catheters were positioned successfully, and thrombosis did not occur during the monitoring. In two patients, an increase in the lactate concentration and a glucose level close to 0 were associated with signs of flap necrosis, with removal on Days 9 and 50. In viable flaps, the mean glucose level was 2.02 mmol/L, the mean lactate level was 8.36 mmol/L, and the mean lactate/pyruvate ratio was 53. Forty percent of the glucose values were below 1 mmol/L, and 50% of the lactate/pyruvate ratio values were above 50—suggesting a specific metabolic pattern because these values would be considered as alert values in soft tissue.ConclusionMonitoring bone free flaps with intraosseous microdialysis is feasible. This technique specifically assesses bone viability, and further studies are now necessary to define the alert values in bone.

Highlights

Most studies of free flap monitoring have found similar success rates (97–99%) and salvage rates (Chae et al, 2015)
Three patients removed accidently their microdialysis catheter on Day 2, and one patient removed it on Day 3
An increase in the lactate concentration and a glucose concentration close to 0 mmol/L were noted in Patients 1 (Table 3 and Figure 3) and 8 (Table 3, Figure 2 and Figure 3); these features were later associated with clinical signs of flap necrosis, such as delayed wound healing, leakage, and typical odor

Summary

Introduction

Most studies of free flap monitoring (including all types of free flaps and reconstructive surgery sites, and various monitoring techniques) have found similar success rates (97–99%) and salvage rates (up to 80%) (Chae et al, 2015). The failure rate in reconstructive surgery with bone free flaps (11–25%, depending on the study) is higher than. The present study's objective was to establish the feasibility of microdialysis with a catheter positioned directly in bone. Fibula or iliac crest free flaps were used in reconstructive head and neck surgery (for cancer, osteoradionecrosis, trauma, or ameloblastoma) and monitored with microdialysis catheters positioned in a hole drilled into the bone. Forty percent of the glucose values were below 1 mmol/L, and 50% of the lactate/pyruvate ratio values were above 50—suggesting a specific metabolic pattern because these values would be considered as alert values in soft tissue. Conclusion: Monitoring bone free flaps with intraosseous microdialysis is feasible This technique assesses bone viability, and further studies are necessary to define the alert values in bone

Results

Discussion

Conclusion