A “watch window” technique for monitoring buried free jejunum flaps during circumferential pharyngolaryngectomy reconstruction

Circumferential pharyngeal reconstruction after total laryngopharyngectomy: A systematic review and network meta-analysis

OBJECTIVE

To compare the functional outcomes of different reconstructive techniques for circumferential pharyngeal reconstruction.

METHODS

A comprehensive electronic search was performed on PubMed/MEDLINE, Cochrane Library, and Google Scholar databases. Retrospective and prospective studies were included. Two independent reviewers extracted thirty-four studies after applying the eligibility criteria. An arm-based network analysis was conducted using a Bayesian hierarchical model. The main outcomes were pharyngo-cutaneous fistula (PCF) incidence, stenosis incidence and feeding tube dependence (FTD) incidence. Network estimates from outcome variables were presented as absolute risks, odds ratio [OR] with 95% credible intervals (CIs), and ranking probability.

RESULTS

A total of 1357 patients were included for 5 different interventions (tubed pectoralis muscle myocutaneous flap, t-PMMCF; tubed anterolateral tight flap, t-ALTF; tubed radial forearm free flap, t-RFFF; free jejunal flap, FJF; U-shaped pectoralis muscle myocutaneous flap, u-PMMCF). FJF showed a 92.8% chance of ranking first in terms of pharyngo-cutaneous fistula prevention (absolute risk: 10%), while the highest PCF incidence (42%) was measured for t-PMMCF. u-PMMCF showed the lowest absolute risk (11%) of stenosis incidence (62.2% chance of ranking first). t-PMMCF (5%), FJF (8%), and u-PMMCF (8%) showed similar results in terms of feeding tube dependence, with a 53.2%, 23.1% and 18.9% chance of ranking first, respectively.

CONCLUSIONS

FJF seems to be the best reconstructive choice after total laryngo-pharyngectomy in terms of PCF, stenosis and FTD incidence. If this reconstructive method is not feasible, a u-PMMCF should be favored over tubed free and pedicled flaps. Further comparative studies are needed to confirm these results.

The use of sentinel skin islands for monitoring buried and semi-buried micro-vascular flaps. Part II: Clinical application

Despite the high success rate of micro-vascular flaps, anastomosis compromise occurs in 5-10% and that can lead to flap failure. Reliable monitoring of the flap is therefore of similar importance to that of the precise surgical procedure itself. Multiple methods have been reported for monitoring of the flap vitality, the first one being direct visual monitoring. In buried flaps direct visualisation is not feasible or is unreliable. In these cases we can extend the buried flap to expose a segment of it to act as a monitoring sentinel. For the purpose of this review we used our clinical experience as a starting point, and for the extended information and expertise we conducted a search of the PubMed database. Over 40 monitoring techniques have been reported to-date. Direct visual monitoring is still generally used method with a reliability of up to 100% and an overall success rate of up to 99%. Direct visualisation remains as the simplest, cheapest and yet a very reliable method of flap monitoring. In this review we provide a description of various possible techniques for externalising part of a buried flap, define the tissues that can be used for this purpose and we summarise the procedures that should be followed to achieve the best reliability and validity of monitoring the skin island.

Modern postoperative monitoring of free flaps

PURPOSE OF REVIEW

Flap failure in microvascular reconstruction is a costly complication with total flap loss being the worst-case scenario. With the aim to rapidly identify a postoperative circulatory problem, some susceptible flaps can be saved by careful clinical monitoring or by various technical monitoring methods. In head and neck surgery, where the flaps are often buried and difficult to monitor clinically, a reliable technical monitoring method would be useful. A broad range of different techniques are in use varying according to practical and personal preferences among clinics and surgeons. However, no evidence for any particular technique being superb has emerged. We review reports of some frequently used and modern free flap monitoring techniques.

RECENT FINDINGS

Clinical monitoring is still the gold standard to which other techniques are compared to. Laser Doppler flowmetry and near-infrared spectroscopy have been reported to identify early circulatory problems, but both techniques are not well suited for buried flaps. Implantable Doppler, flow coupler, partial tissue oxygen pressure and microdialysis are invasive monitoring methods suitable for buried flaps.

SUMMARY

More research with practical and clinically relevant parameters, that is flap salvage rate, false positive rate and cost-efficiency are needed before objective comparisons between different monitoring techniques can be made.

Postoperative monitoring of the free jejunal flap: use of colour duplex and systematic review of available techniques

Introduction The free jejunal flap represents the gold standard for circumferential defects in upper digestive tract reconstruction. It is a technically demanding procedure with significant failure rates. Unrecognised failure leads to flap necrosis and potentially fatal sequelae, including sepsis and carotid artery bleed. Despite these catastrophic consequences, however, there remains no consensus on an optimum method for postoperative flap monitoring. Our unit has pioneered the use of external colour duplex ultrasound to monitor flap vascularity. We describe this technique and systematically review other published monitoring systems. Materials and methods A patient underwent oesophageal reconstruction using a jejunal free flap. Monitoring commenced immediately via external application of a colour duplex probe over the flap's vascular pedicle to facilitate flow volume assessment. Further bi-daily assessments were successfully used to monitor the postoperative viability of the flap. The systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results Six alternative monitoring techniques were identified: exteriorised jejunal segment, implantable Doppler probe, watch window, microdialysis, microendoscopy and reflectance photoplethysmography. Discussion Exteriorised jejunal segment and implantable Doppler probe are most commonly described, yet both are associated with high false positive rates, which is particularly significant in a patient demographic facing increased general anaesthetic risk. Most other techniques remain experimental. External colour Doppler ultrasound provides the surgeon with immediate reassurance following the reconstruction, requires minimal training to use, and eliminates the need for revisional procedures. Conclusion Our initial experience suggests that external colour Doppler ultrasound has exciting potential as an efficient and noninvasive technique for monitoring the free jejunal flap.