Comparative Study of Small Vessel (under 0.8 mm) Anastomosed Free Flap and Larger Vessel (over 0.8 mm) Anastomosed Free Flap; Does Supermicrosurgery Provide Sufficient Blood Flow to the Free Flap?

BACKGROUND

 This study aimed to quantify the blood flow of free flaps and compare the blood flow of small vessel (<0.8 mm) and larger vessel (>0.8 mm) anastomosed free flaps.

METHODS

 This retrospective study included patients treated successfully with a perforator free flap in the lower extremity between June 2015 and March 2017. A color duplex ultrasound system measured the flow volume through the pedicle by analyzing the mean flow peak velocity, flow volume, and flow volume per 100 g of the flap.

RESULTS

 A total of 69 patients were enrolled in this study. There was no statistical difference in peak velocity between the small vessel anastomosed free flap (25.2 ± 5.6) and larger vessel anastomosed free flap (26.5 ± 5.4). Flow volume (6.8 ± 4.2 vs. 6.3 ± 3.6) and flow volume/100 g (3.6 ± 3.9 vs. 6.2 ± 6.9) also did not show significant differences.

CONCLUSION

 Small vessel (<0.8 mm) free flaps showed similar flow velocity and flow volume to larger vessel (>0.8 mm) anastomosed free flaps. Blood flow to the small vessel anastomosed free flap was sufficient despite its small vessel size.

Maximizing the Versatility of Thin Flap from the Groin Area as a Workhorse Flap: The Selective Use of Superficial Circumflex Iliac Artery Perforator (SCIP) Free Flap and Superficial Inferior Epigastric Artery (SIEA) Free Flap with Precise Preoperative Planning

BACKGROUND

 This study aimed to evaluate the usefulness of the selective use of the superficial circumflex iliac artery perforator (SCIP) and the superficial inferior epigastric artery (SIEA) flap as a workhorse flap from the groin area with precise preoperative surgical planning.

METHODS

 A total of 79 free flap reconstructions were performed in the study period; 35 SCIP free flaps and 19 SIEA free flaps were performed in the study period. Detailed preoperative surgical planning was performed using computed tomography (CT) angiography and color Doppler ultrasound. Detailed anatomical information of the flaps and reconstructive outcomes were evaluated.

RESULTS

 Flap characteristics between SCIP free flaps and SIEA free flaps were similar. The average transverse distance of the perforator from anterior superior iliac spine was 15.91 cm in SCIP free flaps and 43.15 cm in SIEA free flaps. The overall flap success rate was 96.4%. Majority of the patients achieved satisfactory contour without debulking surgery. Donor site morbidity was minimal with one case of wound dehiscence.

CONCLUSION

 The selective use of the SCIP and SIEA free flap in groin area is a safe and useful technique. The surgical outcomes were reliable and similar between the SCIP and SIEA free flaps. Preoperative vascular planning using CT angiography and color Doppler ultrasound is essential for selecting the proper flap.

Effect of Simvastatin Use in Free Tissue Transfer: An Experimental Study in a Rat Epigastric Free Flap Model

BACKGROUND

 Statins are traditionally used in lowering cholesterol and low-density lipoprotein biosynthesis, but recent reports show their beneficial effect on microcirculation. The aim of this study was to investigate the effect of simvastatin on the microcirculation and in conjunction with aspirin in a rat free epigastric flap model.

METHODS

 Thirty-six Sprague-Dawley rats were divided into group A (control, n = 12), group B (simvastatin treated, n = 12), and group C (simvastatin and aspirin, n = 12). Bilateral free epigastric skin flap was used to evaluate the effect. At 48 hours, flaps biopsies were evaluated for inflammatory activity, nitric oxide content, and thrombomodulin regulation in the endothelial lining of microvessels. Flap survival was evaluated on day 7.

RESULTS

 The diameter of microvessels and nitric oxide activity in groups B and C were significantly higher than in group A (p < 0.005 and 0.015, respectively). The perivascular inflammatory cell infiltrates and intravascular adhesions were predominant in group A compared with groups B and C (p < 0.005). Groups B and C demonstrated significant higher degree of thrombomodulin expression. The flap survival rate on day 7 was 70.8% for group A, and 87.5% and 91.7%, respectively, for groups B and C without significance between the two (p = 0.675).

CONCLUSION

 Simvastatin significantly improves the free flap survival by effective anti-inflammatory, vasodilator, and anticoagulant activities. Combined therapy did not have an antagonistic effect and further study is needed to see synergistic action through different mechanisms.

Direction of Flap Rotation in Propeller Flaps: Does It Really Matter?

Background This article investigates the effect of 180° rotating propeller flaps and evaluates whether each flap has a “preferable” rotating direction.

Methods Part 1 evaluates the flap pedicle velocity and flow volume in neutral, 180°counterclockwise, and clockwise rotated position for 29 consecutive flaps. The data (velocity and volume) were divided into three groups: neutral, high value, and low value group then evaluated. Part 2 compares the outcome from the prospective study where a preferable rotation with high value was selected against 29 patients from 2012 to 2016 who had the same operation without selecting a preferable rotation direction.

Results In part 1, the three groups (neutral, high value, and low value groups) showed mean velocity of 28.06 ± 7.94, 31.92 ± 10.22, 24.41 ± 8.12 cm/s, respectively, and mean volume of 6.11 ± 4.95, 6.83 ± 6.69, 4.62 ± 3.55 mL/min, respectively. The mean velocity and volume of the perforator in the high value group were significantly higher than that in the low value group (p = 0.0001). In part 2, although no statistical significance in the outcome was observed, there were two cases of total, two cases of partial flap loss, and three cases of wound dehiscence in the patients where preferable rotations was not selected compared with only two wound dehiscence for flaps with preferable rotation.

Conclusion The velocity and flow of the flap are significantly different based on the rotation direction of the flap. Using the preferred rotation direction with statistically higher value of velocity and flow may increase the overall outcome of the propeller flap, especially where larger flaps are used.

Lipo-prostaglandin E1 increases immediate arterial maximal flow velocity of free flap in patients undergoing reconstructive surgery

BACKGROUND

In free flap surgery, the maintenance of proper blood flow after anastomosis of flap pedicle vessels is important. Lipo-prostaglandin E1 (lipo-PGE1) has been empirically administered to prevent blood flow insufficiency in a free flap reconstruction. We tested our hypothesis that lipo-PGE1 administration increases the arterial inflow of free flap. We also evaluated lipo-PGE1-related haemodynamic changes and complications.

METHODS

Thirty-seven patients who underwent free flap reconstruction were analysed. Lipo-PGE1 was administered 10 minutes after the vascular anastomosis of the free flap. The maximal blood flow velocity was measured at the free flap pedicle artery before and 30 minutes after lipo-PGE1 administration using duplex ultrasonography. The primary outcome was the difference in the maximal blood flow velocity before and 30 minutes after lipo-PGE1 administration. The arterial blood pressure, heart rate, cardiac output, stroke volume variation, and pulse pressure variation were measured simultaneously. Lipo-PGE1-related complications such as hypotension, bradycardia, hypothermia, facial flushing, diarrhoea, apnoea, and seizure were also investigated.

RESULTS

The maximal blood flow velocity was significantly increased at 30 minutes after lipo-PGE1 administration compared to the level before lipo-PGE1 administration (mean (standard deviation): 26.3 (8.7) cm/s vs 22.5 (8.0) cm/s, P = 0.002). The haemodynamic variables were not significantly different before and 30 minutes after lipo-PGE1 administration. No lipo-PGE1-related complications occurred.

CONCLUSIONS

Lipo-PGE1 significantly increases the maximal blood flow velocity without complications in patients undergoing free flap reconstruction and may be an effective and safe method of maintaining adequate blood flow in these cases.

A Mobile Application for Wound Assessment and Treatment: Findings of a User Trial

The D+Wound Solution is a mobile phone application (app) that assists users in the assessment and treatment of the wound. The app has 6 components for assessment: need for debridement, infection control, revascularization, and exudate control; whether it is chronic; and finally, the top surface of the skin. These components are named D.I.R.E.C.T. The app makes you review these components as an algorithm to provide a reasonable solution for dressing. It is designed to understand the status of the wound and provide a practical treatment idea for wound care providers. A total of 118 nurses were divided into 2 groups, designated as experienced and less-experienced groups, and surveyed. Both groups found the app to be helpful in making a treatment plan. However, the less-experienced group found it to be significantly more useful in assessing the wound ( P = .026) but difficult to understand the logic. The experienced group found the logic to be significantly easier to understand ( P = .018) and had significantly higher similarities ( P = .015) in treatment protocols compared with the less-experienced group. We may conclude that this app has a logical algorithm resembling experienced wound caregivers and is more useful in the less-experienced group.