Abstract

Among several minimally invasive adrenalectomy techniques, lateral transperitoneal adrenalectomy (LTA) is the procedure of choice for benign adrenal tumors, however, posterior retroperitoneoscopic adrenalectomy (PRA) is an alternative that is increasing in popularity. This study compared the outcomes of these two approaches. Since a single surgeon started adrenalectomy, LTA had been performed exclusively until PRA was adopted and became the standard treatment. Therefore, the consecutive patients were allocated into two groups according to the date of surgery: the first group received LTA and the second group received PRA. LTA was performed in 29 patients and PRA in 19 patients. There was no difference in sex, age, body mass index, clinical diagnosis, and tumor size between the LTA and the PRA group. The PRA group showed less blood loss (117.0 mL vs. 58.5 mL, p = 0.035) and tended to have a shorter operating time (92.2 minutes vs. 78.1 minutes, p = 0.054) and less pain score on postoperative Day 1 (3.8 vs. 3.0, p = 0.095) and Day 2 (3.2 vs. 2.5, p = 0.051). The mean operation time was significantly shorter for patients in the PRA group undergoing right adrenalectomy (109.2 minutes vs. 80.5 minutes, p = 0.009), but those undergoing left adrenalectomy had a similar operating time to the LTA group (83.2 minutes vs. 74.8 minutes, p = 0.380). PRA is a good alternative operative technique for an endocrine surgeon who is experienced in the transperitoneal approach.

Abstract

Dexmedetomidine has been proposed as a novel anesthetic adjuvant. However, it remains unclear whether peripheral administration of dexmedetomidine is safe and effective to reduce acute postoperative pain. This study aimed to examine the effects of dexmedetomidine on neuropathic pain. Adult male Sprague-Dawley rats were anaesthetized and randomly allocated into four groups (n = 8): Groups S, R, RD1, and RD5 were injected with saline, 0.5% ropivacaine, 0.5% ropivacaine combined with 1 μg dexmedetomidine, and 0.5% ropivacaine combined with 5 μg dexmedetomidine, respectively, around the saphenous nerve. Then, the rats were subjected to skin/muscle incision and retraction (SMIR) surgery in the medial thigh. Mechanical and heat sensitivity was evaluated and morphology of the dorsal root ganglion (DRG) neurons was observed by electron microscopy. Some 62.5%, 50%, 12.5%, and 25% of rats developed mechanical hypersensitivity in Groups S, R, RD1, and RD5, respectively. The number of swollen mitochondria in DRG neurons was significantly more in Group S (257.2 ± 60.9) and Group R (291.6 ± 82.1) than in Group RD1 (97.2 ± 33.3) and Group RD5 (13.6 ± 17.9). In addition, the edema in endoplasmic reticulum and Golgi apparatus was decreased in Group RD1 and Group RD5 compared with Group S and Group R. Peripheral administration of dexmedetomidine improves mechanical and heat hyperalgesia and mitigates postoperative pain.