Comparison of the incidence of venous thromboembolism between epidural and general anesthesia for total knee arthroplasty: a retrospective study

BACKGROUND: Substantial variation exists in the reported rates of postoperative venous thromboembolism (VTE) following total knee arthroplasty (TKA) in the Asian population. This retrospective study aimed to compare the early postoperative VTE incidence between patients managed with epidural anesthesia and those managed by general anesthesia at the time of TKA. METHODS: We reviewed 589 cases of unilateral primary TKA performed between January 2011 and June 2014. We selected epidural versus general anesthesia groups as the main anesthetic choices, with postoperative patient-controlled analgesia. All the patients underwent deep vein thrombosis (DVT) computed tomography angiography on postoperative day 7. The incidence of DVT and pulmonary thromboembolism (PTE) was evaluated and compared between epidural and general anesthesia. RESULTS: The overall incidence of VTE was 8.0% in the two groups together. The incidence did not differ between the groups. The odds ratio in the generalized estimation equations analysis showed a higher incidence of DVT and PTE in the epidural group; however, this result was not statistically significant. Although, the odds ratio for age showed that the risk of developing DVT and PTE increased 1.12 times per year. CONCLUSIONS: Total VTE incidence was not significantly different between patients who underwent general anesthesia and those who underwent epidural anesthesia for TKA. A prospective multicenter study is required to evaluate the nature of the Korean VTE status in major orthopedic surgeries, and to prepare guidelines and protocols for medical prophylaxis for DVT and PTE in Korea.

Change of Taste and Sensory after Tonsillectomy and Laryngomicrosurgery / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Postoperative taste and sensory changes are regarded as unusual and minor complications of tonsillectomy and laryngomicrosurgery. This study aimed to identify incidence, cause, and duration of postoperative taste and sensory changes. SUBJECTS AND METHOD: With 20 patients who underwent tonsillectomy and 20 patients who underwent laryngomicrosurgery, we have prospectively studied postoperative taste and sensory changes using questionnaires with regard to symptoms at 1(st), 7(th) , 14(th) and 28(th) days after the surgery. The thresholds of sweet, sour, salty and bitter tastes were measured by spatial taste test. Also, we have checked pre-operatively and post-operatively about the serum level of zinc and copper. RESULTS: Five patients (25%) who underwent tonsillectomy and 3 patients (15%) who underwent laryngomicrosurgery suffered from changes in tastes. Four patients (20%) and 5 patients (25%) showed the sensory change. Especially, the bitter taste threshold changed in the posterior tongue (p<0.05). Post-operative zinc deficiency was detected on 1 patient. Subjective taste and sensory change disappeared within 28 days. In spatial taste test, the threshold for bitter taste increased on the 1st post-operative day at the posterior tongue, but it returned almost to the preoperative level within 28days. CONCLUSION: Taste and sensory change after tonsillectomy and laryngomicrosurgery are not unusual complications. If there were no neural damage, taste and sensory change were transient and disappeared within 28 days. The main cause of transient taste and sensory change seemed to be due to the compression of tongue, and sometimes, to postoperative zinc deficiency.

A Case of Salivary Duct Carcinoma Ex Pleomorphic Adenoma of Parotid Gland / 대한이비인후과학회지

Carcinoma ex pleomorphic adenoma of the salivary gland is a relatively uncommon tumor that accounts for roughly 4% of all malignancies at this location. The lesion occurs when a malignant tumor arises in the epithelial component of a pleomorphic adenoma. It usually arises in the parotid gland. Typically, it is a high grade carcinoma, frequently leading to metastasis and disease-related death. We experienced a case of a salivary duct carcinoma that arose in the epithelial component of a pleomorphic adenoma in the parotid gland with neck metastasis. After total parotidectomy and modified radical neck dissection, he was given 10, 980 cGy of radiation postoperatively for 7 weeks. The clinicopathologic feature of this tumor are presented with a review of literatures.

Effects of Preserving the Posterior Branch of the Greater Auricular Nerve at Parotidectomy on Postoperative Peri-Auricular Sensation / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The posterior branch of the greater auricular nerve is a sensory nerve that serves the skin over the mastoid process and the postero-inferior region of the auricle. The greater auricular nerve is often sacrificed in parotidectomy, even though its posterior branch can be preserved. By cautious dissection of the greater auricular nerve it is possible to preserve the posterior branch in 69 per cent of the operations. However, the efficiency of this procedure is not clear. So, we have compared the patients whose nerve had been preserved with those sacrificed, to evaluate the validity of the posterior branch of greater auricular nerve preservation during parotidectomy. SUBJECTS AND METHOD: Thirty patients undergoing parotidectomy were divided into two groups. Fifteen patients underwent parotidectomy with preservation of the posterior branch of the greater auricular nerve (group A) and they were compared with fifteen patients who underwent parotidectomy with sacrificing the nerve (group B). Using questionnaire, we have researched about numbness, pain or other subjective symptoms on peri-auricular area after parotidectomy and the function of the nerve has been tested by two point tactile discrimination test and temperature sensitivity test. RESULTS: Postoperatively, twenty-nine patients felt lack of sensitivity, pain, itching or other symptoms. These symptoms recovered within 12 months, subjectively. However, in group B, permanent sensory loss was found in three patients. The two-point discrimination test revealed in group B, the decreased sensitivity on the operated side in comparison with the unoperated side (p=0.008). It also showed the decreased sensitivity on operated side in group B, compare with group A (p=0.012). CONCLUSION: From this study, despites of no significant difference on subjective symptoms, there was objective improvement on function of the greater auricular nerve. It seems reasonable to spare the greater auricular nerve during parotidectomy.

The Effectiveness of Sternocleidomastoid Muscle Flap in Preventing Frey's Syndrome Following Parotidectomy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Frey's syndrome is one of the potential sequelae of parotidectomy. Various medical and surgical treatments have been used in attempt to avoid this embarrassing condition. Recently, interposing barriers between the overlying skin flap and the parotid bed, such as the sternocleidomastoid (SCM) muscle flap, have been used to prevent this condition. The purpose of this study was to evaluate the preventive impact of using this flap on the incidence of Frey's syndrome and to identify the degree of severity in this syndrome between the use of SCM flap and no muscle flap. SUBJECTS AND METHOD: 40 patients who underwent superficial parotidectomy from June 1996 to August 2003 were divided into two groups. One group had SCM flap reconstruction (n=20), and the other did not (n=20). A subjective clinical questionnaire and the objective Minor's starch test were used to evaluate the incidence of this syndrome. A grading system was used to divide Frey's syndrome into mild or severe Frey's syndrome to determine its severity. The test of Pearson-x2 was applied. RESULTS: The association between sweating, flushing, or pain and the use of the flap was not significant. Also, there was no significant association with Minor's starch test and the use of the flap. There was a significant association with mild Frey's syndrome and the presence of the flap (p=0.014). CONCLUSION: It would seem that the sternocleidomastoid muscle flap does not reduce the incidence of Frey's syndrome, but does decrease the degree of severity in Frey's syndrome.

A Case of Adenoid Cystic Carcinoma Ex Pleomorphic Adenoma of Submandibular Gland / 대한이비인후과학회지

Carcinoma ex pleomorphic adenoma is a rare neoplasm of the salivary gland. This lesion occurs when a malignant tumor arises in the epithelial component of a pleomorphic adenoma. The patient was a 35-year-old male with ovoid shaped and protruding submandibular mass that has been present for 3 weeks. The initial radiologic diagnosis was suspicious of malignancy and the cytologic finding by fine needle aspiration biopsy showed highly malignant cells. After submandibular gland extirpation and supraomohyoid neck dissection, the histologic examination revealed that tumor was composed partly of a benign pleomorphic adenoma and partly of an adenoid cystic carcinoma component with areas of calcification, capsular invasion, and perineural invasion. The adenoid cystic carcinoma component showed a cribriform pattern, also known as "Swiss cheese appearance". We additionally did postoperative radiotherapy for 7 weeks. We present a rare case of carcinoma ex pleomorphic adenoma with adenoid cystic carcinoma in the submandibular gland.