Evaluation of distributed practice schedules on retention of a newly acquired surgical skill: a randomized trial.

BACKGROUND: practice influences new skill acquisition. The aim of this study was to prospectively investigate the impact of practice distribution (weekly vs monthly) on complex motor skill (end-side vascular anastomosis) acquisition and 4-month retention. METHODS: twenty-four surgical interns were randomly assigned to weekly training for 4 weeks or monthly training for 4 months, with equal total training times. Performance was assessed before training, immediately after training, after the completion of distributed training, and 4 months later. RESULTS: there was no statistical difference in surgical skill acquisition and retention between the weekly and monthly scheduled groups, as measured by procedural checklist scores, global rating scores of operative performance, final product analysis, and overall performance or assessment of operative "competence." CONCLUSIONS: distributed practice results in improvement and retention of a newly acquired surgical skill independent of weekly or monthly practice schedules. Flexibility in a surgical skills laboratory curriculum is possible without adversely affecting training.

Effects of Tisseel and FloSeal on primary ischemic time in a rat fasciocutaneous free flap model.

OBJECTIVES: Free flaps are the technique of choice for reconstruction of defects resulting from extirpation of tumors of the head and neck. Advances in microsurgical technique have resulted in success rates of greater than 95%. Numerous intraoperative factors, ranging from technical issues to topically applied agents, can complicate the outcome of microsurgical free tissue transfer. Synthetic tissue adhesives and hemostatic agents are playing an ever-increasing role in reconstructive surgery. The safety of these factors in free flap surgery has not been ascertained. STUDY DESIGN: Animal Care Committee live rat model. METHODS: Male Sprague-Dawley rats were divided into three groups: group I, Control; group 2, FloSeal; group 3, Tisseel. In each group, a 3 x 6 cm ventral fasciocutaneous groin flap based on the left superficial epigastric artery was elevated and the experimental material applied beneath the flap and around the flap pedicle prior to suturing of the flap back to the wound bed. The experimental materials consisted of 0.2 mL saline in the control group, 0.5 mL FloSeal, and 0.2 mL Tisseel. In phase I of this study, the effect of each treatment on flap survival was assessed by survival at postoperative day 4. In phase II of the study, the effects of these agents on ischemic tolerance was investigated. Five rats in each treatment group were exposed to ischemic times of 6, 8, 10, and 12 hours. Survival of the flap was assessed 7 days after reversal of the ischemia. Probit curves and the critical ischemic time (CIT50) were calculated. RESULTS: All flaps survived the 2-hour period of ischemia and were viable at postoperative day 4. Flap survival from group 1 (Control), group 2 (FloSeal), and group 3 (Tisseel) at the various ischemic times was as follows: at 6 hours, 80%, 80%, and 80%, respectively; at 8 hours, 80%, 80%, 60%; at 10 hours, 60%, 33%, 40%; at 12 hours, 20%, 20%, 0%. The CIT50 for the Control, FloSeal, and Tisseel groups was 9.4, 9.0, and 7.0 hours, respectively.CONCLUSIONS FloSeal, a thrombin-based hemostatic agent, and Tisseel, a fibrin glue, displayed no adverse effect on flap survival in this model.

The effect of 2 sealants (FloSeal and Tisseel) on fasciocutaneous flap revascularization.

BACKGROUND: Fasciocutaneous tissue transfer is one of the most common procedures performed in head and neck reconstructive surgery. These composite tissues can be transferred as either a free flap or a pedicled flap. Free tissue transfer has become the reconstructive modality of choice following head and neck oncologic ablation. Synthetic tissue adhesives and hemostatic agents are rapidly gaining popularity in reconstructive surgery. Their ability to decrease bleeding and promote flap sealing and healing has led to a proliferation in their use. To our knowledge, the short-term effect of these substances on healing, as measured by flap revascularization, has not been systematically investigated. METHODS: Fifty-six male Sprague-Dawley rats were divided into 3 groups: a control group, a matrix hemostatic sealant (FloSeal) group, and a 2-component fibrin sealant (Tisseel) group. In each group, the rats had a 3 x 6-cm fasciocutaneous flap based on the inferior epigastric artery elevated and exposed to 2 hours of primary ischemia. In the control group, 0.2 mL of isotonic sodium chloride solution was placed between the flap and its bed, while in the experimental groups, 0.5 mL of FloSeal or 0.2 mL of Tisseel was applied to the wound before closure. Each group was then divided into groups of 5 rats. Each of these groups then had their pedicle divided on postischemic day 4, 5, 6, or 7. The percentage survival of the flap was measured 7 days after pedicle ligation. RESULTS: There was no statistical difference in flap survival of rats treated with isotonic sodium chloride solution, Tisseel, or FloSeal. Ligation of the flap pedicle on days 4, 5, 6, or 7 did not result in any difference in flap survival among the 3 groups. CONCLUSION: The FloSeal and Tisseel demonstrate no short-term detrimental effect on flap survival nor do they seem to affect revascularization in a fasciocutaneous free flap model.