A realistic model for vasectomy reversal training using swine testicles

Purpose: To evaluate the viability of the porcine vas deferens as a realistic microsurgical training model for vasectomy reversal Methods: The model uses swine testicles (vas deferent), which are usually discarded in large street markets since they are not part of Brazilian cuisine. The spermatic cord was carefully dissected, and the vas deferens were isolated, measuring 10 cm in length. A paper quadrilateral with 5 cm2 was built to delimit the surgical training field. The objective of the model is to simulate only the microsurgical step when the vas deferens are already isolated. The parameters analyzed were: feasibility for reproducing the technique, patency before and after performing the vasovasostomy, cost of the model, ease of acquisition, ease of handling, execution time, and model reproducibility. Results: The simulator presented low cost. All models made were viable with a texture similar to human, with positive patency obtained in 100% of the procedures. The internal and external diameters of the vas deferens varied between 0.2-0.4 mm and 2-3 mm, respectively, with a mean length of 9 ± 1.2 cm. The total procedure time was 43.28 ± 3.22 minutes. Conclusions: The realistic model presented proved to be viable for carrying out vasectomy reversal training, due to its low cost, easy acquisition, and easy handling, and providing similar tissue characteristics to humans.

Anatomorphometry of the brachial plexus under high-definition system: an experimental study in rats

Purpose: To study the anatomorphometry of the plexus brachialis (PB) of rats under a high-definition video system. Methods: Ten male Wistar rats discarded from other research that did not interfere in the morphology of the animal, respecting the principle of reduction, were used. All animals were submitted to the same protocol. Initially, the cervical region was shaved. The animals were placed in a dorsal position. A single elbow-to-elbow incision was performed and dissection started at the deltopectoral sulcus. The procedures were performed under a video system. To measure the structures, the Image J software was used. Results: All the PB evaluated originated from the C5-T1 spinal nerves. C5 and C6 converged to form the truncus superior, the root of C7 originated the truncus medius, and the confluence of C8 and T1 originated the truncus inferior. It was found the union of C7, C8, and T1 to form truncus inferomedialis instead of separate medial and inferior truncus. C8 (1.31 mm) was the thickest root, the truncus inferior (1.80 mm) and the nerve radialis (1.02 mm), were the thickest. Conclusions: The anatomy of the PB is comparable to humans, admitting variations. The videomagnification system is useful to perform microsurgical dissection.

Incisional hernia repair in rats: description of the sublay technique under videomagnification system

Purpose: To describe the technique of sublay correction of incisional hernia in Wistar rats under videomagnification system. Methods: Five male rats of the species Rattus norvegicus, of the Wistar lineage, with body weight between 250­350 g and 60 days old were used. Incisional hernia was inducted in all animals. After that, the incisional hernia was immediately corrected by the sublay method. Results: There were no cases of recurrence of the incisional hernia after placement of the polypropylene mesh using the sublay technique. No postoperative complications were observed. Conclusions: The technique is suitable for execution in Wistar rats.

Anatomical description of the ventral and dorsal cervical rootlets in rats: A microsurgical study

Purpose: To describe the anatomical aspects of the cervical rootlets and to quantify the number of rootlets that compose C1 to T1. Methods: Twenty male rats were used in this study. The dorsal rootlets from C1 to T1 were analyzed. To study the ventral rootlets, the posterior root avulsion was performed using a microhook, allowing exposure of the ventral roots through manipulation of the denticulate ligament and arachnoid mater. The parameters analyzed were the number of ventral and dorsal rootlets by side and level. Results: The formation of the respective spinal nerve was observed in the spinal roots the union of the ventral and dorsal roots. In four animals the C1 spinal root had no dorsal and/or ventral contribution. There is no normal pattern of numerical normality of the dorsal and ventral rootlets. The average number of fascicles per root was 4.08, with a slight superiority on the left side. There was a slight superiority of the dorsal rootlets compared to the ventral rootlets. Conclusions: This investigation was the first to study cervical rootlets in rats. In 20% of the sample studied, the dorsal root of C1 was absent mainly on the left side. There is a nonlinear numerical increase from C1 to T1 in the rootlets. There is a numerical predominance of cervical fascicles on the left side, confronting several studies related to the functional predominance of right laterality, requiring new studies that correlate these variables.

A new anesthetic protocol to medullary nerve roots access in rats

ABSTRACT Purpose: To describe a new anesthetic protocol medullary and nerve roots access and in Rattus norvegicus. Methods: Seventy female Wistar rats (n=70) were used. The animals were randomly divided into two laminectomy groups: cervical (n=40) and thoracic (n=30). In cervical group, a right posterior hemilaminectomy was performed to access the nerve roots. In thoracic group, a laminectomy of the eighth thoracic vertebra was accomplished. Thirty-five rats (20 cervical and 15 thoracic) were submitted to old anesthetic protocol (ketamine 70 mg/kg plus xylazine 10 mg/kg); and the 35 other animals (20 cervical and 15 thoracic) were submitted to a new anesthetic protocol (ketamine 60 mg/kg,xylazine 8 mg/kg and fentanyl 0.03 mg/kg). Results: The time to complete induction was 4.15 ±1.20 minin ketamine, xylazine and fentanyl group, and it was 4.09 ±1.47 min in the ketamine and xylazine group. There was no correlation in the time required to perform the cervical laminectomy in the old anesthetic protocol. In all groups, the animals submitted to the old anesthetic protocol had a higher level of pain on the first and third postoperative days than the animals submitted to the new anesthetic protocol. Conclusions: The new anesthetic protocol reduces the surgical time, allows better maintenance of the anesthetic plan, and brings more satisfactory postoperative recovery.

Criteria for assessing peripheral nerve injury: behavioral and functional assessment in non-operated Wistar rats

Purpose To evaluate the normality pattern in functional tests of peripheral nerves. Methods Sixty female and sixty male Wistar rats were submitted to vibrissae movement and nictitating reflex for facial nerve; grooming test and grasping test for brachial plexus; and walking tracking test and horizontal ladder test for lumbar plexus. The tests were performed separately, with an interval of seven days between each. Results All animals showed the best score in vibrissae movement, nictitating reflex, grooming test, and horizontal ladder test. The best score was acquired for the first time in more than 90% of animals. The mean of strength on the grasping test was 133.46±12.08g for the right and 121.74±8.73g for the left anterior paw. There was a difference between the right and left sides. There was no difference between the groups according to sex. There is no statistical difference comparing all functional indexes between sex, independent of the side analyzed. The peroneal functional index showed higher levels than the sciatic and tibial functional index on both sides and sex. Conclusions The behavioral and functional assessment of peripheral nerve regeneration are low-cost, easy to perform, and reliable tests. However, they need to be performed by experienced researchers to avoid misinterpretation.(AU)

New training model using chickens intestine for pediatric intestinal anastomosis

Purpose: To develop a new low-cost, easy-to-make and available training model using chickens intestine for infant intestinal anastomosis.Methods: Segments of chicken intestine were used to create an intestinal anastomosis simulator. We tried to perform an end-to-end, end-to-side and side-to-side anastomosis. Handsewn sutured anastomosis were performed in single layered with interrupted prolene 5-0 suture. The parameters analyzed were cost, intestines diameter and length, anastomosis patency and flow-through and leakage amount. Results: In all cases it was possible to make the anastomosis in double layered without difficulties, different from the usual ones. There was a positive patency at all anastomoses after the end of the procedure, with no need for reinterventions. Conclusion: The new training model using chickens intestine for infant intestinal anastomosis is low-cost, easy-to-make and easy available.(AU)

Does the type of electrode affect the electromyoneurographic parameters in rats?

Purpose:To evaluate if the type of electrode (needle vs. surface) affects the electromyoneurography parameters in rats.Methods:Twenty male rats were anesthetized, then compound muscle action potential were recorded using a Neuropack S1 MEB- 9400©. All animals were submitted to two electroneuromyography analysis: first with surface electrode and then by needle electrode. We evaluated the latency, amplitude, duration and area of the negative peak of the gastrocnemius and cranial tibial muscles.Results:There were no significant differences between the groups in the mean of duration, latency, amplitude or area of the negative peak in gastrocnemius and cranial tibial muscles.Conclusion:The type of electrode does not affect the electroneuromyography parameters.(AU)

Influence of oophorectomy on glycemia and lipidogram

Purpose: To verify the influence of oophorectomy on lipidogram and glycemia. Methods: Fifty six female rats were divided into the following 7 groups (n = 8): group 1 - sham group, group 2 - oophorectomy 30 days, group 3 - oophorectomy 35 days, group 4 - oophorectomy 40 days, group 5 - oophorectomy 45 days, group 6 - oophorectomy 70 days, group 7 - oophorectomy 55 days. Animals were following by number of days according the group. Was evaluated the serum levels of glucose and lipid profile. Results: The oophorectomized rats presented higher glycemia. Groups 3, 4, 6 and 7 had a higher glycemia and LDL levels (except for group 6) and groups 6 and 7 had lowest levels of HDL. Group 7 had highest level of VLDL than oophorectomy groups. There was no difference in triglycerides levels. Conclusion: Oophorectomy was related to dyslipidemia and insulin resistance, mainly after 50th days.(AU)

Influence of tramadol on functional recovery of acute spinal cord injury in rats

Purpose:To evaluate the influence tramadol on functional recovery of acute spinal cord injury in rats.Methods:Ten rats were divided into two groups (n = 5). All animals were submitted by a laminectomy and spinal cord injury at eighth thoracic vertebra. In control group, the rats didnt receive any analgesic. In tramadol group, the rats received tramadol 4mg/Kg at 12/12h until 5 days by subcutaneous. Animals were following by fourteen days. Was evaluated the Basso, Beattie, Bresnahan scale (locomotor evaluation) and Rat Grimace Scale (pain evaluation) at four periods.Results:There no difference between the groups in locomotor evaluation in all periods evaluated (p>0.05) and in both groups there was a partial recover of function. The tramadol group show a lower pain levels at the first, third and seventh postoperatively days when comparing to the control group.Conclusion:The tramadol as an analgesic agent dont influence on functional recovery of acute spinal cord injury in rats.(AU)