A Comparative Study of the Percutaneous versus Intraoral Technique for Mental Nerve Block

Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant.     

Effect of totally absorbable implant volume on wound infection rate: Study of 2500 operated fractures, osteotomies, and ligament injuries

Between November 1984 and January 1994 in our department, a total of 2500 patients were treated with totally absorbable internal fixation devices. We studied these patients and analyzed results with regard to the volume of the absorbable implants and the development of wound infection. Of the 2500 patients 2044 were trauma patients and 456 were operated on for orthopedic disease. In 1466 patients treated with implants made of self-reinforced polyglycolic acid (SR-PGA) only, the patients who developed wound infection had a higher implant volume (P=0.07) than those who did not; this difference was close to statistical significance. In the 446 patients who received only implants made of self-reinforced poly-l-lactic acid (SR-PLLA), the 5 who developed wound infection had a mean implant volume more than three times that of the non-infected patients (P=0.01). We found that in the patients treated with the earlier SR-PGA implants, which contained a green staining material, there was no correlation between implant volume and incidence of wound infections. On the other hand, both the non-stained SR-PGA implants, which have been in clinical use since 1989, and the SR-PLLA implants, seem to be more predictable in terms of wound infections. We believe that this difference, is largely due to the lower level of tissue reactions with these newer implants.     

Clinical problem-solving using video simulation: an investigation

This paper examines the use of videotape simulation as a research method for the exploration of clinical problem-solving, the challenges posed and the strategies employed to overcome the difficulties encountered are discussed. The simulation forms part of a larger comparative study of outcomes of pre-registration nurse education programmes, commissioned by the English National Board for Nursing, Midwifery and Health Visiting.     

原发性中枢神经系统淋巴瘤35例临床分析

目的 探讨原发性中枢神经系统淋巴瘤的临床特点、诊断及治疗方法。方法 回顾性分析35例原发性中枢神经系统淋巴瘤的临床资料、病理特征及术前诊断方法。结果 本组男19例，女16例，男女比例为1．2：1。年龄26～72岁，平均年龄52岁。所有患者人免疫缺陷病毒(HIV)检查均为阴性。临床症状主要表现为颅内压增高、肢体无力、瘫痪和神经精神症状。57％的患者病史短于4周，发病急，病情进展快。肿瘤多位于额部、颚顶部和基底节区，本组共35例52个肿瘤，其中16例为多发性肿瘤(45．7％)。结论 原发性中枢神经系统淋巴瘤是一组异质性肿瘤，侵袭性大。病史短，发病急，病情进展快，常发生于幕上大脑半球，易多发，术前诊断困难．预后差．     

小儿头孢菌素致抗生素相关性腹泻64例分析

目的了解头孢菌素导致抗生素相关性腹泻的基本情况。方法对64例头孢菌素致抗生素相关性腹泻进行临床观察。结果本组头孢菌素致抗生素相关性腹泻以6个月～3岁年龄组发生率最高。其中第3代头孢菌素所致抗生素相关性腹泻的腹泻程度重于第1代。临床表现和实验室检查均缺乏特异性。结论头孢菌素致抗生素相关性腹泻比较常见,应引起临床医师在用药时的重视。     

乳腺癌术后双肺及骨转移

疾病的正确诊断和合理治疗是患者和医务工作者共同的心愿。在广东省人民医院肿瘤中心，吴一龙教授指导临床医生应用循证医学理论进行肿瘤的多学科综合治疗，开展临床病例讨论。讨论会上各学科共同围绕一个病例或一个病种进行会诊，临床、病理、B超、放射影像等资料齐全。除相关科室提前准备的中心性发言外，到会人员各抒己见，气氛热烈。参会人员受益匪浅，提高了对疑难病例的诊治水平。为了将他们的诊治经验传播出去，让更多的临床医生获益，我刊开辟“循证病例讨论”栏目，希望广大医务工作者关注此栏目。[编者按]     

Development and evaluation of an allocation committee to distribute community placements on an equitable basis between universities: Our experience with the University Placement Allocation Committee

The present paper outlines the development and evaluation of an allocation committee to distribute community placements on an equitable basis between universities. Although based on our experience in South Australia with the University Placement Allocation Committee (UPAC), the primary goal is to outline the steps that would be useful if placement coordinators at other universities in Australia decided to establish and maintain an allocation committee. A survey of field supervisors was also conducted and field supervisors endorsed UPAC as a constructive mechanism for allocating community placements.     

The structure of memorized knowledge in students and clinicians: an explanation for diagnostic expertise

This paper provides for the first time evidence of a consistent difference in the memory structures of novice and expert clinicians. The diagnostic performance of first- and third-year clinical medical students, senior house officers, registrars and consultants on four clinical problems in general medicine was studied. Comparisons were made of all diagnostic interpretations offered and the forceful features (personally important pieces of information which act as a key to particular memory structures which in turn give rise to the clinical interpretation) from which these were derived. Results demonstrate that the numbers of interpretations made and the numbers of forceful features identified did not differ significantly between groups (P greater than 0.05). However, the actual interpretations made in three out of four cases, and the actual forceful features identified in all cases, did differ significantly between groups (P less than 0.05). The numbers of interpretations made by all groups were large and demonstrated enormous variability. Highly individualized multiple responses to clinical information are associated with easy diagnoses. We conclude that there is no difference between groups of differing clinical experience in the breadth of thought but that there are marked differences in the precise content and structure of thought. This allows coherent explanation of variation in diagnostic expertise with clinical experience. The significance of the findings is discussed.     

Assessment of postoperative pain: impact of clinical experience and professional role

Background: Unrelieved postoperative pain is still reported to be a rather common clinical problem which may be related to inadequate routines for pain assessment. Therefore, the aim of the study was to describe strategies used by experienced and less experienced nurses and physicians in their assessment of postoperative pain and to relate different approaches, clinical experience, and professional role to the accuracy of the pain ratings.
Methods: Data collection was based on repeated interviews with nurses (n=30) and physicians (n=30) in connection with clinical pain assessments (n=180) including VASscoring
Results: Commonly used strategies in the pain assessment were: - how the patient looks, - what the patient says, - the manner of talking, and - past experience of similar circumstances. The mean VAS-score given by the patients (6.1±21.1) was significantly (P<0.001) higher than that rated by the staff members (4.9±21.2). Nurses as well as physicians overestimated low and underestimated high levels of pain indicated by the patients. The accuracy of the ratings by nurses, especially by more experienced ones (≤10 years in nursing), was found to be less precise than that of physicians. The pain assessment of these very experienced nurses was characterized by a systematic underestimation.
Conclusions: The present study emphasizes a need for definition of more precise strategies for clinical postoperative pain assessment which better take into consideration the pain experiences and needs of individual patients     

Application of fluorescence in situ hybridization techniques in clinical genetics: use of two alphoid repeat probes detecting the centromeres of chromosomes 13 and 21 or chromosomes 14 and 22, respectively

Two cloned DNA fragments, one derived from an alpha satellite subfamily common to chromosomes 13 and 21, and the other derived from a similar subfamily common to chromosomes 14 and 22, have been used as biotinylated probes in in situ hybridization studies. Under high stringency conditions, chromosome specific centromeric labelling can be obtained. The applications of this technique in clinical situations are illustrated on metaphases from a fetus with trisomy 21, a fetus with trisomy 13, and a child with clinical features of cat-eye syndrome.