Maintenance of anaesthesia

Key goals for the maintenance phase of general anaesthesia are the provision of surgical anaesthesia while maintaining physiological parameters at levels that preserve organ function and avoid injury. Maintenance can be achieved with either inhaled or intravenous anaesthetic agents. A good understanding of the physiochemical properties of these agents is necessary for effective manipulation of depth of anaesthesia at any stage. Drugs suitable for total intravenous anaesthesia are mainly those with short context-sensitive half-times, such as propofol, remifentanil, and dexmedetomidine. Target-controlled infusion pumps utilize three compartment models in complex calculations to achieve the desired effect-site concentration. Monitoring during anaesthesia has been proven to reduce risk in the perioperative period. Sustained vigilance and good exchange of information at handover between anaesthetists are other essential aspects of safe anaesthesia during the maintenance phase.     

Preoperative MRI for oral tongue squamous cell carcinoma: timing and correlation to histopathology

Magnetic resonance imaging (MRI) is an integral part of the evaluation of local and regional disease in tongue squamous cell carcinoma prior to surgery. The aim of this study was to evaluate the accuracy of MRI in assessing tumour dimensions, as well as the impact of the time-lag from diagnostic biopsy on the accuracy of MRI. The medical records of 64 patients with tongue carcinoma were reviewed retrospectively. Tumour maximum diameter and tumour depth of invasion were compared between pathology and MRI (T1- and T2-weighted). MRI-derived maximum tumour diameter and depth of invasion correlated strongly with histopathology: T1-weighted (r = 0.700 and r = 0.813, respectively) and T2-weighted (r = 0.734 and r = 0.834, respectively). A significant correlation was found between measurements on T1 and T2 MRI for both parameters (P = 0.955 and P = 0.984, respectively). The accuracy rate of MRI for T-staging of early tumours was low: 10% for T1 tumours; 39.3% for T2 tumours. A time-lag of less than 2 weeks between the diagnostic biopsy and MRI adversely affected the correlation of tumour dimensions. MRI is a reliable tool for evaluating tongue carcinoma; however, it overestimates early tumours. A 2-week delay after diagnostic biopsy is desired before completing an MRI. Alternatively, if logistics allow, a pre-biopsy MRI is preferred, especially for T1–T2 tumours.     

比较两种切口行下颌第三磨牙拔除术的临床效果

比较采用封套瓣切口与角形切口在拔出下颌中位阻生第三磨牙中的临床效果。方法 选取 2022年1月-6月于蚌埠医学院第一附属医院口腔颌面外科行下颌第三磨牙拔除术的60例患者为研究对象， 随机分为对照组和观察组，每组30例。对照组采用角形切口行下颌第三磨牙拔除术，观察组采用封套瓣切 口行下颌第三磨牙拔除术，比较两组手术时间、出血程度、牙周探诊深度、疼痛程度、伤口愈合情况、肿 胀程度及张口度。结果 两组手术时间、出血程度及牙周探诊深度比较，差异无统计学意义（P ＞0.05）； 观察组术后7 d V AS评分低于对照组（P ＜0 .0 5）；观察组术后3、7 d L a n d r y评分均高于对照组 （P ＜0.05）；观察组术后3 d肿胀程度低于对照组，张口度高于对照组（P ＜0.05）。结论 相比于角形切 口，采用封套瓣切口行下颌第三磨牙拔除术在减轻疼痛和肿胀、促进早期张口和伤口愈合方面的效果更为 理想，有利于促进患者恢复。     

Is modified Carnoy’s solution as effective as Carnoy’s solution in terms of amount of bone necrosis and depth of penetration?

Carnoy’s solution, a chemical cauterisation agent, has been indicated as one of the adjuvant treatment modalities for odontogenic keratocyst. In 2000, after the ban of chloroform many surgeons adopted the use of Modified Carnoy’s solution. The purpose of this study is to compare the depth of penetration and amount of bone necrosis of Carnoy’s versus Modified Carnoy’s solution on the mandible of Wistar rats at different time intervals. Twenty-six male Wistar rats of six to eight weeks old, weighing approximately 150–200 grams, were allocated for this study. The predictor variables were type of solution and application time. The outcome variable was depth of penetration and amount of bone necrosis. Carnoy’s solution was applied on the defect on the right side of the mandible and Modified Carnoy’s solution on the left side for five minutes on eight rats, eight minutes on eight rats, and 10 minutes on eight rats. All specimens were subjected to histomorphometric analysis done using Mia image AR software. Univariate ANOVA test, and paired sample t test was done to compare the results. The depth of penetration for Carnoy’s solution was more than Modified Carnoy’s solution in the three different exposure times. Statistically significant results were observed at five minutes and eight minutes. The amount of bone necrosis was more in Modified Carnoy’s solution. The results were not statistically significant at the three different exposure times. To conclude, when one wants to use Modified Carnoy’s solution, the minimum exposure time should be 10 minutes to achieve similar results as those of Carnoy’s solution.     

Should an elective contralateral neck dissection be performed in midline-reaching squamous cell carcinomas of the oral cavity and oropharynx?

Objectiveto compare the rate of occult contralateral neck metastases (OCNM) in oral and oropharyngeal squamous cell carcinomas (SCC) reaching or crossing the midline and to identify risk factors for OCNM.Materials and methodswe conducted a single-center retrospective study of oral and oropharyngeal SCC with contralateral cN0 neck. The cohort was divided into a midline-reaching (MR; approaching the midline from up to 10 mm) group and a midline-crossing (MC; exceeding the midline by up to 10 mm) group. Clinical N-status was assessed by a radiologist specializing in head and neck imaging. All patients underwent contralateral elective neck dissection (END).ResultsA total of 98 patients were included in this study, 59 in the MR group and 39 in the MC group. OCNM were present in 17.3% of patients, 20.3% in the MR group and 12.8% in the MC group (p = 0.336). In multivariable analysis, MR/MC status as well as distance from the midline (in mm) were not identified as risk factors for OCNM. Conversely, oropharyngeal primary and clinical N-status above N1 were significantly associated with a higher risk of OCNM, with odds ratios (OR) of 3.98 (95% CI = 1.08–14.60; p = 0.037) and 3.41 (95% CI = 1.07–10.85; p = 0.038) respectively.Conclusionin patients with oral and oropharyngeal SCC extending close to or beyond the midline, tumor origin and clinical N-status should carry the most weight when dictating the indications for contralateral END, rather than the midline involvement in itself.     

Extended validation of the Relational Depth Frequency Scale: Retest reliability,divergent validity,criterion validity with psychotherapy satisfaction,and measurement invariance in UK- and US-stratified samples

Background

The Relational Depth Frequency Scale (RDFS) assesses moments of profound connection in psychotherapy, associated with therapeutic benefit. To date, the RDFS has not been tested for its retest reliability, divergent and criterion validity, and measurement invariance, nor has it been tested in stratified samples of psychotherapy patients.

Methods

Two stratified online samples of United Kingdom (n = 514) and United States (n = 402) psychotherapy patients filled out the RDFS, the Brief Social Desirability Scale (BSDS); and the Satisfaction with Therapy and Therapist Scale-revised (STTS-R). Two subsamples of patients (United Kingdom: n = 50 and United States: n = 203) filled out the RDFS again after 1 month.

Results

Reliability for the six-item RDFS were excellent in United Kingdom and United States samples (Cronbach's α = 0.91 and 0.92; retest r = 0.73 and r = 0.76). Divergent (r = 0.10 and r = 0.12) and criterion validity (r = 0.69; and r = 0.70) were good. Full scalar invariance was established across countries, genders, and time.

Conclusion

This contributes important evidence to the validity of the RDFS. Future research should assess predictive validity against psychotherapy outcomes and replicate these analyses in diverse samples.