Standardization of the Rat Dorsal Random Pattern (McFarlane) Flap Model and Evaluation of the Pharmacological Agents Aiming to Salvage Partial Flap Necrosis: A Systematic Review and a Meta-analysis

Time-related variations in viability of random pattern skin flaps: An experimental study in rats

Chronobiological variations are in the fabric of life. The first ideas regarding the possible effects of circadian rhythm on surgical outcomes were published in the early 2000s. Some studies support and oppose this idea. The lack of experimental evidence in a controlled setting has led to this study. This study aimed to explore the chronobiological implications of surgical outcomes. The rats were divided into four groups. A random pattern dorsal skin flaps were elevated in all groups at six h intervals. Flap necrosis rates and melatonin, oxidant, and antioxidant factors were studied. Flap survival was better in the 06:00 h group. The flap necrosis was higher in the 18:00 h group. Some of the biochemical parameters displayed circadian variations. As an independent variable, the time of surgical intervention changed the flap survival rates. It should be noted that the study was held in a nocturnal animal model thus the pattern of flap survival can be in reversed fashion in a clinical scenario. This study is the first experimental evidence for "Chronosurgery" in a controlled setting. Further studies in all aspects of surgical disciplines are required.

One-Pot Synthesis of Bioadhesive Double-Network Hydrogel Patch as Disposable Wound Dressing

Inventions of materials to achieve biocompatibility, bioadhesion, and easy manufacturing are the urgent demand for promoting wound healing in clinical treatment. Hyaluronic acid (HA) is probably the ideal candidate for current dressing materials due to its well-known biocompatibility. However, the unavoidable problem for HA dressings is their inherent low adhesiveness to wounds, which severely impairs their treatment efficacy, especially during body movement. Here, we report a one-pot facile fabrication of hybrid double-network polydopamine-HA (PDA-HA) hydrogel with significantly enhanced adhesiveness compared to the HA hydrogel. Besides the easy manufacturing and promoted effectiveness, the PDA-HA hydrogel could be vacuum-dried to form a patch, further benefitting from the convenience for storage and distribution. When applied on the wound, the PDA-HA patch quickly rehydrated by absorbing exudate and stuck tightly to the wound. The applied PDA-HA patches keep the wounds covered for more than 7 days against strenuous exercise. Thus, mouse full-thickness wounds treated with the PDA-HA patches exhibited increased healing rates, where epithelization was finished within 14 days. Moreover, the hydrogel dressing exhibited promoting effects on vascularization and cell proliferation/migration. Together with the easy manufacturing procedure, good adhesion/adaptation, and promotion of wound healing, the PDA-HA patch holds great potential for future clinical translation.

Comparison of Hand-Held Doppler and Indocyanine Green Angiography in Preoperative Design of Expanded Forehead Flaps for Nasal Reconstruction

BACKGROUND

Despite the different approaches for detection of perforators, methods of vascular mapping of the expanded forehead flap for nasal reconstruction are rarely described. This article aimed to present our experience in the preoperative design of the expanded forehead flap for nasal reconstruction and to compare the clinical practice of hand-held Doppler and indocyanine green angiography (ICGA) in vascular mapping for nasal reconstruction with the expanded forehead flap.

METHODS

From October 2019 to April 2022, 26 patients underwent nasal reconstruction using expanded forehead flap. The authors performed preoperative vascular mapping on 16 patients by hand-held Doppler alone, and on 10 patients by hand-held Doppler and ICGA primary outcomes considered were the visualization of the main vascular course of the flap obtained by hand-held Doppler or ICGA, intraoperative observation of the flap, and its postoperative complications.

RESULTS

Indocyanine green angiography provides a better detection in distal flap and the branches of the supratrochlear artery. Vein detection by ICGA generally corresponds to the results obtained by the combination of hand-held Doppler and transillumination test. In the group that only used hand-held Doppler, 2 patients presented hemodynamic complications in the margin of the flap and 1 patient presented partial necrosis postoperatively. No complication was found in the group that used ICGA.

CONCLUSIONS

It is recommended to use the ICGA for preoperative planning, as it yields highly accurate vascular courses. As an alternative to other methods, hand-held Doppler is also an effective tool.

LEVEL OF EVIDENCE

IV.