Objective To explore the feasibil ity, indications, and effects of vacuum seal ing drainage (VSD) combined with flaps for repairing skin and soft tissue defects of lower l imbs. Methods From June 2006 to November 2009, 15 patients with skin and soft tissue defects of lower l imbs were treated with VSD combined with flaps (VSD group, n=5) and only flaps (non-VSD group, n=10). In VSD group, there were 3 males and 2 females with an average age of 46 years (range, 32-69 years), including 3 cases of traffic accident injury, 1 case of skin necrosis after amputation, and 1 case of plate exposureafter operation. The locations were lower leg in 1 case, ankle in 2 cases, dorsum of foot in 1 case, and forefoot in 1 case. The defect size ranged from 6.5 cm × 6.0 cm to 23.0 cm × 17.0 cm. The disease course ranged from 2 hours to 2 months. In non- VSD group, there were 5 males and 5 females with an average age of 50 years (range, 23-58 years), including 6 cases of traffic accident injury, 1 case of crush injury in earthquake, 1 case of osteomyel itis, and 2 cases of plate exposure after operation. The locations were lower leg in 1 case, ankle in 3 cases, forefeet and dorsum of feet in 4 cases, and heel in 2 cases. The defect size ranged from 4 cm × 4 cm to 20 cm × 12 cm. The disease course ranged from 1 hour to 2 months. There was no significant difference in general data between 2 groups (P gt; 0.05). Results In VSD group, the preoperative hospital ization days, postoperative hospital ization days, and total hospital ization days were (11.8 ± 9.5), (35.4 ± 28.3), and (47.2 ± 35.8) days, respectively; the size of flap was (232.8 ± 142.0) cm2; and the infection rate after VSD-use was 0. In non-VSD group, the preoperative hospital ization days, postoperative hospital ization days, and total hospital ization days were (25.8 ± 12.4), (33.9 ± 28.1), and (59.7 ± 32.4) days, respectively; the size of flap was (97.3 ± 93.6) cm2; and the infection rate after 8 to 14 days of regular therapy was 80%. There were significant differences in the preoperative hospital ization days and the size of flap between 2 groups (P lt; 0.05). All flaps were al ive except 3 partial necrosis (1 case in VSD group, 2 cases in non-VSD group). The 3 flaps healed by skin grafting and suturing. The donor sites healed by first intention. All patients were followed up 5-41 months (22.1 months on average). All flaps were good in color, texture, and wear abil ity. Conclusion It is effective to apply VSD combined with proper flap to repair skin and soft tissue defects of lower l imbs, which can cut down infection rate, improve blood supply, shorten the preoperative hospital ization days, and facil itate heal ing, but whether it can shorten the postoperative hospital ization days and total hospital ization days need further research.
Photoplethysmography (PPG) is often affected by interference, which could lead to incorrect judgment of physiological information. Therefore, performing a quality assessment before extracting physiological information is crucial. This paper proposed a new PPG signal quality assessment by fusing multi-class features with multi-scale series information to address the problems of traditional machine learning methods with low accuracy and deep learning methods requiring a large number of samples for training. The multi-class features were extracted to reduce the dependence on the number of samples, and the multi-scale series information was extracted by a multi-scale convolutional neural network and bidirectional long short-term memory to improve the accuracy. The proposed method obtained the highest accuracy of 94.21%. It showed the best performance in all sensitivity, specificity, precision, and F1-score metrics, compared with 6 quality assessment methods on 14 700 samples from 7 experiments. This paper provides a new method for quality assessment in small samples of PPG signals and quality information mining, which is expected to be used for accurate extraction and monitoring of clinical and daily PPG physiological information.