Enhancing endoscopic measurement: validating a quantitative method for polyp size and location estimation in upper gastrointestinal endoscopy.

BACKGROUND: Accurate measurement of polyps size is crucial in predicting malignancy, planning relevant intervention strategies and surveillance schedules. Endoscopists' visual estimations can lack precision. This study builds on our prior research, with the aim to evaluate a recently developed quantitative method to measure the polyp size and location accurately during a simulated endoscopy session. METHODS: The quantitative method merges information about endoscopic positions obtained from an electromagnetic tracking sensor, with corresponding points on the images of the segmented polyp border. This yields real-scale 3D coordinates of the border of the polyp. By utilising the sensor, positions of any anatomical landmarks are attainable, enabling the estimation of a polyp's location relative to them. To verify the method's reliability and accuracy, simulated endoscopies were conducted in pig stomachs, where polyps were artificially created and assessed in a test-retest manner. The polyp measurements were subsequently compared against clipper measurements. RESULTS: The average size of the fifteen polyps evaluated was approximately 12 ± 4.3 mm, ranging from 5 to 20 mm. The test-retest reliability, measured by the Intraclass Correlation Coefficient (ICC) for polyp size estimation, demonstrated an absolute agreement of 0.991 (95% CI 0.973-0.997, p < 0.05). Bland & Altman analysis revealed a mean estimation difference of - 0.17 mm (- 2.03%) for polyp size and, a mean difference of - 0.4 mm (- 0.21%) for polyp location. Both differences were statistically non-significant (p > 0.05). When comparing the proposed method with calliper measurements, the Bland & Altman plots showed 95% of size estimation differences between - 1.4 and 1.8 mm (- 13 to 17.4%) which was not significant (p > 0.05). CONCLUSIONS: The proposed method of measurements of polyp size and location was found to be highly accurate, offering great potential for clinical implementation to improve polyp assessment. This level of performance represents a notable improvement over visual estimation technique used in clinical practice.

Endoscopic measurement of the size of gastrointestinal polyps using an electromagnetic tracking system and computer vision-based algorithm.

PURPOSE: Polyp size is an important factor that may influence diagnosis and clinical management decision, but estimation by visual inspection during endoscopy is often difficult and subject to error. The purpose of this study is to develop a quantitative approach that enables an accurate and objective measurement of polyp size and to study the feasibility of the method. METHODS: We attempted to estimate polyp size and location relative to the gastro-oesophageal junction by integrating data from an electromagnetic tracking sensor and endoscopic images. This method is based on estimation of the three-dimensional coordinates of the borders of the polyp by combining the endoscope camera position and the corresponding points along the polyp border in endoscopic images using a computer vision-based algorithm. We evaluated the proposed method using a simulated upper gastrointestinal endoscopy model. RESULTS: The difference between the mean of ten measurements of one artificial polyp and its actual size (10 mm in diameter) was 0.86 mm. Similarly, the difference between the mean of ten measurements of the polyp distance from the gastroesophageal junction and its actual distance (~ 22 cm) was 1.28 mm. Our results show that the changes in camera positions in which the images were taken and the quality of the polyp segmentation have the most impact on the accuracy of polyp size estimation. CONCLUSION: This study demonstrated an innovative approach to endoscopic measurements using motion tracking technologies and computer vision and demonstrated its accuracy in determining the size and location of the polyp. The observed magnitude of error is clinically acceptable, and the measurements are available immediately after the images captured. To enhance accuracy, it is recommended to avoid identical images and instead utilise control wheels on the endoscope for capturing different views. Future work should further evaluate this innovative method during clinical endoscopic procedures.

The effect of metformin on vitamin B12 level in pediatric patients.

PURPOSE: Metformin is a common medication for patients with hyperglycemia. In adults, one well-documented side effect of metformin is vitamin B12 deficiency. However, this side effect has rarely been studied in pediatric patients. This study examined the changes of vitamin B12 level in pediatric patients being treated with metformin. METHODS: Data were collected from pediatric patients (n=151) with at least 3 months of consecutive metformin intake. The effects of dose of metformin on the mean vitamin B12 level were investigated at 6, 12, 24, and 36 months. The effect of compliance of metformin intake on vitamin B12 level also was studied. RESULTS: There was no significant decrease in mean vitamin B12 level at 6, 12, 24, or 36 months in patients treated with metformin. Mean vitamin B12 decrease was only noticeable (p<0.05) in patients taking a high dose of metformin with good compliance. Despite this change, the mean vitamin B12 remained well within the normal reference range. Furthermore, of the 151 patients studied, only 1 demonstrated vitamin B12 deficiency after 12 months of treatment. However, his B12 level was normal at 24 and 36 months without any vitamin B12 supplements. CONCLUSION: Our findings suggest that metformin treatment in children does not cause vitamin B12 deficiency; however, the effect of long-term consistent high-dose treatment on vitamin B12 level remains unknown.

Prevalence and Sonographic Detection of Gallbladder Polyps in a Western European Population.

BACKGROUND: Gallbladder cancer is rare but associated with significant morbidity and mortality necessitating the early identification of premalignant and malignant lesions to improve overall prognosis. Despite limited evidence regarding the effectiveness of transabdominal ultrasound (US) in the detection of gallbladder polyps, it plays a key role in current European guidelines. The aim of this study was to investigate gallbladder polyp prevalence in a western European population and assess the diagnostic accuracy of transabdominal US. METHODS: Data from patients who underwent cholecystectomy for US detected gallbladder polypoid lesions at four hospitals in Ireland and the United Kingdom between 2010 and 2018 were retrospectively collected. Patient demographics, ultrasonographic, and histopathologic findings were analyzed. RESULTS: A total of 134 patients underwent cholecystectomy for US-detected gallbladder polyps. After histopathologic examination, pseudopolyps were found in 75 (56%) specimens with dysplastic or malignant polyps seen in only six (4.5%) specimens. Mean size for neoplastic polyps was 33 mm. The positive predictive value for US in detecting neoplastic polyps in this study was 4.5%, which is significantly lower than the 10%-15% reported previously. CONCLUSIONS: Although the prevalence of neoplastic polyps in this study is higher than in the previous literature, the distribution of pseudopolyps and true polyps is as expected. With all malignant polyps being >10 mm in diameter, these findings support the current size thresholds stated in European guidelines. The poor diagnostic accuracy of US demonstrated may have led to significant number of patients undergoing unnecessary surgical intervention, further supporting the argument for improved strategies for the investigation of gallbladder polyps.

Stimulation of the wrist acupuncture point PC6 for preventing postoperative nausea and vomiting.

BACKGROUND: Postoperative nausea and vomiting (PONV) are common complications following surgery and anaesthesia. Antiemetic drugs are only partially effective in preventing PONV. An alternative approach is to stimulate the PC6 acupoint on the wrist. This is an update of a Cochrane review first published in 2004, updated in 2009 and now in 2015. OBJECTIVES: To determine the effectiveness and safety of PC6 acupoint stimulation with or without antiemetic drug versus sham or antiemetic drug for the prevention of PONV in people undergoing surgery. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library, Issue 12, 2014), MEDLINE (January 2008 to December 2014), EMBASE (January 2008 to December 2014), ISI Web of Science (January 2008 to December 2014), World Health Organization Clinical Trials Registry, ClinicalTrials.gov, and reference lists of articles to identify additional studies. We applied no language restrictions. SELECTION CRITERIA: All randomized trials of techniques that stimulated the PC6 acupoint compared with sham treatment or drug therapy, or combined PC6 acupoint and drug therapy compared to drug therapy, for the prevention of PONV. Interventions used in these trials included acupuncture, electro-acupuncture, transcutaneous electrical acupoint stimulation, transcutaneous nerve stimulation, laser stimulation, capsicum plaster, acu-stimulation device, and acupressure in people undergoing surgery. Primary outcomes were the incidences of nausea and vomiting after surgery. Secondary outcomes were the need for rescue antiemetic therapy and adverse effects. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted the data and assessed the risk of bias domains for each trial. We used a random-effects model and reported risk ratio (RR) with associated 95% confidence interval (95% CI). We used trial sequential analyses to help provide information on when we had reached firm evidence in cumulative meta-analyses of the primary outcomes, based on a 30% risk ratio reduction in PONV. MAIN RESULTS: We included 59 trials involving 7667 participants. We rated two trials at low risk of bias in all domains (selection, attrition, reporting, blinding and other). We rated 25 trials at high risk in one or more risk-of-bias domains. Compared with sham treatment, PC6 acupoint stimulation significantly reduced the incidence of nausea (RR 0.68, 95% CI 0.60 to 0.77; 40 trials, 4742 participants), vomiting (RR 0.60, 95% CI 0.51 to 0.71; 45 trials, 5147 participants) and the need for rescue antiemetics (RR 0.64, 95% CI 0.55 to 0.73; 39 trials, 4622 participants). As heterogeneity among trials was substantial and there were study limitations, we rated the quality of evidence as low. Using trial sequential analysis, the required information size and boundary for benefit were reached for both primary outcomes.PC6 acupoint stimulation was compared with six different types of antiemetic drugs (metoclopramide, cyclizine, prochlorperazine, droperidol. ondansetron and dexamethasone). There was no difference between PC6 acupoint stimulation and antiemetic drugs in the incidence of nausea (RR 0.91, 95% CI 0.75 to 1.10; 14 trials, 1332 participants), vomiting (RR 0.93, 95% CI 0.74 to 1.17; 19 trials, 1708 participants), or the need for rescue antiemetics (RR 0.87, 95% CI 0.65 to 1.16; 9 trials, 895 participants). We rated the quality of evidence as moderate, due to the study limitations. Using trial sequential analyses, the futility boundary was crossed before the required information size was surpassed for both primary outcomes.Compared to antiemetic drugs, the combination of PC6 acupoint stimulation and antiemetic therapy reduced the incidence of vomiting (RR 0.56, 95% CI 0.35 to 0.91; 9 trials, 687 participants) but not nausea (RR 0.79, 95% CI 0.55 to 1.13; 8 trials, 642 participants). We rated the quality of evidence as very low, due to substantial heterogeneity among trials, study limitations and imprecision. Using trial sequential analysis, none of the boundaries for benefit, harm or futility were crossed for PONV. The need for rescue antiemetic was lower in the combination PC6 acupoint stimulation and antiemetic group than the antiemetic group (RR 0.61, 95% CI 0.44 to 0.86; 5 trials, 419 participants).The side effects associated with PC6 acupoint stimulation were minor, transient and self-limiting (e.g. skin irritation, blistering, redness and pain) in 14 trials. Publication bias was not apparent in the contour-enhanced funnel plots. AUTHORS' CONCLUSIONS: There is low-quality evidence supporting the use of PC6 acupoint stimulation over sham. Compared to the last update in 2009, no further sham comparison trials are needed. We found that there is moderate-quality evidence showing no difference between PC6 acupoint stimulation and antiemetic drugs to prevent PONV. Further PC6 acupoint stimulation versus antiemetic trials are futile in showing a significant difference, which is a new finding in this update. There is inconclusive evidence supporting the use of a combined strategy of PC6 acupoint stimulation and antiemetic drug over drug prophylaxis, and further high-quality trials are needed.

Introducing Final-Year Medical Students to Pocket-Sized Ultrasound Imaging: Teaching Transthoracic Echocardiography on a 2-Week Anesthesia Rotation.

PROBLEM: The availability of less expensive and smaller ultrasound machines has enabled the use of ultrasound in virtually all major medical/surgical disciplines. Some medical schools have incorporated point-of-care ultrasound training into their undergraduate curriculum, whereas many postgraduate programs have made ultrasound training a standard. The Chinese University of Hong Kong has charged its Department of Anaesthesia and Intensive Care to spearhead the introduction of ultrasound into the final-year medical curriculum by introducing handheld transthoracic echocardiography as part of perioperative assessment. INTERVENTION: All 133 final-year students completed a 2-week anesthesia rotation, which began with a half-day session consisting of a lecture and hands-on practice session during which they learned 9 basic transthoracic echocardiography views using 4 basic ultrasound probe positions. CONTEXT: Each student was required to perform a transthoracic echocardiography-examine under supervision of 1 patient/week for 2 weeks, and their results were compared against that of the supervisor's. Most patients were elective cardiac surgery patients. One long question on transthoracic echocardiography was included in their end-of-year surgery examination paper. Students provided feedback on their experience. OUTCOME: Most students learned the basic transthoracic echocardiography views fairly efficiently and had variable, though generally favorable, success rates in identifying obvious cardiac anomalies, including use of color Doppler. A few common mistakes were identified but were easily correctable. Logistics for mobilizing enough bedside supervision were challenging. Students reported positive feedback on the teaching initiative. LESSONS LEARNED: We were able to execute a successful short training course on transthoracic echocardiography during the final-year medical degree anesthesia rotation. Our initiative may set an example for other clinical departments to design similar courses pertinent to their specialties and syllabuses.

Risk factors for multiple sclerosis, neuromyelitis optica and transverse myelitis.

BACKGROUND: Little is known about risk factors for neuromyelitis optica (NMO) or transverse myelitis (TM). OBJECTIVE: The objective of this paper is to evaluate whether established multiple sclerosis (MS) risk factors, including smoking history, a history of infectious mononucleosis (IM), anti-EBNA1 Ab titers and HLA-DR15 are associated with NMO or TM. METHODS: We conducted a case-control study among participants in the Accelerated Cure Project for Multiple Sclerosis (ACP) Repository, which includes patients with MS, NMO and TM. Controls include related and unrelated individuals without evidence of demyelinating disease. Analyses included 1237 cases of MS, 98 cases of NMO, 133 cases of TM and 488 healthy controls. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to assess the association between smoking, HLA-DR15, anti-EBNA1 Ab titers and a history of IM adjusting for gender, study site and ethnicity. RESULTS: Overall, the association between smoking, IM, HLA-DR15 and anti-EBNA1 Ab titers and odds of MS were as expected and no significant interactions were observed. However, there was little evidence of association between these MS risk factors and odds of NMO or TM. CONCLUSIONS: Established MS risk factors do not appear to be associated with susceptibility to TM or NMO and, among MS patients, these risk factors appear to act independently.

Cannula malposition during antegrade cerebral perfusion for aortic surgery: role of cerebral oximetry.

PURPOSE: To describe the use of cerebral oximetry to detect a lack of right cerebral perfusion resulting from a malpositioned catheter used for antegrade cerebral perfusion during deep hypothermic circulatory arrest (DHCA). The simple corrective surgical adjustment that followed averted a potentially serious complication. CLINICAL FEATURES: A 57-yr-old male with a type-A aortic dissection undergoing DHCA required antegrade cerebral perfusion for cerebral protection. Catheters were placed accordingly in the left common carotid and brachiocephalic arteries. Whereas frontal cerebral oximetry immediately improved on the left, it did not improve on the right. It was immediately suspected that the tip of the brachiocephalic cannula had advanced into the right subclavian artery, thus depriving the right common carotid artery of blood flow. The problem resolved upon slight withdrawal of the cannula. CONCLUSION: Vigilance in anesthesia should not stop during DHCA or cardiopulmonary bypass. Cerebral oximetry may provide important information leading to actions that improve brain protection. Vigilances proved important in this case where the cannula tip used for antegrade cerebral perfusion was advanced too far into the right subclavian artery.

Biomaterials-based modulation of the immune system.

The immune system is traditionally considered from the perspective of defending against bacterial or viral infections. However, foreign materials like implants can also illicit immune responses. These immune responses are mediated by a large number of molecular signals, including cytokines, antibodies and reactive radical species, and cell types, including macrophages, neutrophils, natural killer cells, T-cells, B-cells, and dendritic cells. Most often, these molecular signals lead to the generation of fibrous encapsulation of the biomaterials, thereby shielding the body from these biomaterials. In this review we will focus on two different types of biomaterials: those that actively modulate the immune response, as seen in antigen delivery vehicles for vaccines, and those that illicit relatively small immune response, which are important for implantable materials. The first serves to actively influence the immune response by co-opting certain immune pathways, while the second tries to mimic the properties of the host in an attempt to remain undetected by the immune system. As these are two very different end points, each type of biomaterial has been studied and developed separately and in recent years, many advances have been made in each respective area, which will be highlighted in this review.

Infectious mononucleosis and risk of breast cancer in a prospective study of women.

PURPOSE: The association between infectious mononucleosis (IM) and risk of breast cancer is unclear; no prospective studies have examined this relationship. We examined self-reported history and age at IM in relation to risk of invasive breast cancer. METHODS: Self-reported history and age at IM were examined in relation to risk of invasive breast cancer in a large cohort of women, the Nurses' Health Study II (81,807 women followed from 1989 to 2007). Through questionnaires, women were asked whether they ever had IM and if so, at what age. During follow-up, 2,349 cases of invasive breast cancer were documented. Cox proportional hazards regression was used to estimate relative risks (RR) and 95 % confidence intervals (CI) for the association of IM with breast cancer. RESULTS: The multivariable-adjusted RR for history of IM and risk of invasive breast cancer was 1.00 (95 % CI: 0.90-1.11). Similar null results were obtained when estrogen receptor/progesterone receptor positive and negative tumors were considered separately. There were no clear patterns of association between age at IM and risk of breast cancer: compared to women with no history of IM, those who were ≤15 years old when they had IM were at lower risk (RR: 0.77; 95 % CI: 0.60, 0.97), but there was no association for women who had IM at ages 16-19, 20-24, or 30+. However, an increased RR (1.45; 95 % CI: 1.02-2.04) was observed for women who had IM at ages 25-29. CONCLUSION: Results of this large prospective study do not support a clear association between history of clinical IM and risk of invasive breast cancer.

Renal dysfunction and CABG.

Renal dysfunction after coronary artery bypass grafting is common and is associated with increased morbidity and mortality. A number of strategies with potential renoprotective effects have been investigated, but no single one has been found to warrant routine use in CABG except fenoldopam in which the data to date appear promising. Other measures such as avoidance of nephrotoxic agents, including recent radiocontrast for coronary angiography, may reduce the incidence of renal dysfunction after cardiac surgery and should be implemented in routine care, whenever possible. The best renal protection strategy remains the same as for other organ protection and consists of optimizing haemodynamics, oxygenation, metabolic states and hydration.

EBNA1 and LMP1 variants in multiple sclerosis cases and controls.

BACKGROUND: Prior infection with Epstein-Barr virus (EBV) is an established risk factor for multiple sclerosis (MS). Some findings from observational studies, including possible epidemics and differences in prevalence, may be explained if different strains of EBV conferred different MS risk. METHODS: DNA was extracted from peripheral lymphocytes obtained from 66 MS cases and 66 age- and cohort-matched controls. Nested polymerase chain reaction (PCR) was performed to amplify the N- and C-terminus regions of EBNA1 and the hyper-variable region of the LMP1 gene. For EBNA1, we compared the presence of the prototype B95.8 vs variant sequence and the presence of multiple strains in MS cases and controls. For LMP1, we considered differences in the proportions of mutations between cases and controls. RESULTS: Comparing the proportion of mutant sequence between MS cases and controls in the EBNA1 N-terminal (0/28 vs 1/27) and C-terminal regions (3/40 vs 8/36) revealed no significant differences (P > 0.05). No individual variants in LMP1 were associated with risk of MS (all P > 0.05). Neither EBNA1 nor LMP1 variation was associated with anti-EBNA1 IgG antibody titers. CONCLUSIONS: These findings do not support a strong role for variation in EBNA1 N-terminus, EBNA1 C-terminus or LMP1 contributing to MS risk.

The costs and benefits of extending the role of the acute pain service on clinical outcomes after major elective surgery.

BACKGROUND: Acute pain services have received widespread acceptance and formal support from institutions and organizations, but available evidence on their costs and benefits is scarce. Although there is good agreement on the provision of acute pain services after many major surgical procedures, there are other procedures for which the benefits are unclear. Data are required to justify any expansion of acute pain services. In this randomized, controlled clinical trial we compared the costs and effects of acute pain service care on clinical outcomes with conventional pain management on the ward. Patients included in the trial were considered by their anesthesiologist to have either arm be suitable for the procedure. METHODS: Four hundred twenty-three patients undergoing major elective surgery were randomized either to an anesthesiologist-led, nurse-based acute pain service group with patient-controlled analgesia or to a control group with IM or IV boluses of opioid analgesia. Both groups were treated with medications to treat opioid-related adverse effects and received the usual care from health professionals assigned to the ward. The main outcome measures were quality of recovery scores, pain intensity measures, global measure of treatment effectiveness, and overall pain treatment cost. Cost-effectiveness acceptability curves were drawn to detect a difference in the joint cost-effect relationship between groups. RESULTS: There was no difference in quality of recovery score on postoperative day 1 between treatment and control groups (mean difference, 0; 95% confidence interval [CI], -0.7 to 0.7; P = 0.94) or in the rate of improvement in quality of recovery score (mean difference, -0.1; 95% CI, -0.4 to 0.1; P = 0.34). The proportion of patients with 1 or more days of highly effective pain management was higher in the acute pain service group than in the control group (86% vs. 75%; P < 0.01). Costs were higher in the acute pain service group (mean difference, US$46; 95% CI, $44 to $48 per patient; P < 0.001). A cost-effectiveness acceptability curve showed that the acute pain service was more cost effective than was control for providing highly effective pain management if the decision maker was willing to pay more than US$546 per patient per 1 day with highly effective treatment. CONCLUSION: In extending the role of the acute pain service to a specific group of major surgical procedures, the acute pain service was likely to be cost effective.

Combined effects of smoking, anti-EBNA antibodies, and HLA-DRB1*1501 on multiple sclerosis risk.

OBJECTIVE: To examine the interplay between smoking, serum antibody titers to the Epstein-Barr virus nuclear antigens (anti-EBNA), and HLA-DR15 on multiple sclerosis (MS) risk. METHODS: Individual and pooled analyses were conducted among 442 cases and 865 controls from 3 MS case-control studies-a nested case-control study in the Nurses' Health Study/Nurses' Health Study II, the Tasmanian MS Study, and a Swedish MS Study. Conditional logistic regression models were used to calculate odds ratios (ORs) and 95% CIs for the association between smoking, anti-EBNA titers, HLA-DR15, and MS risk. Study estimates were pooled using inverse variance weights to determine a combined effect and p value. RESULTS: Among MS cases, anti-EBNA titers were significantly higher in ever smokers compared to never smokers. The increased risk of MS associated with high anti-EBNA Ab titers was stronger among ever smokers (OR = 3.9, 95% CI = 2.7-5.7) compared to never smokers (OR = 1.8, 95% CI = 1.4-2.3; p for interaction = 0.001). The increased risk of MS associated with a history of smoking was no longer evident after adjustment for anti-EBNA Ab titers. No modification or confounding by HLA-DR15 was observed. The increased risk of MS associated with ever smoking was only observed among those who had high anti-EBNA titers (OR = 1.7, 95% CI = 1.1-2.6). CONCLUSIONS: Smoking appears to enhance the association between high anti-EBNA titer and increased multiple sclerosis (MS) risk. The association between HLA-DR15 and MS risk is independent of smoking. Further work is necessary to elucidate possible biologic mechanisms to explain this finding.

Family history of melanoma and Parkinson disease risk.

BACKGROUND: Co-occurrence of Parkinson disease (PD) and melanoma has been reported in numerous studies. If this was due to common genetic mechanisms, a positive family history of melanoma would be associated with an excessive PD risk, independent of environmental risk factors for PD. METHODS: We prospectively examined associations between a family history of melanoma and PD among 157,036 men and women free of PD at baseline (1990 for men and 1982 for women) who participated in 2 ongoing US cohorts: the Health Professional Follow-up Study and the Nurses' Health Study. Information on family history of melanoma in parents or siblings was assessed via questionnaire. Relative risks and 95% confidence intervals were estimated using Cox proportional hazards models and pooled using a fixed-effects model. RESULTS: During 14-20 years follow-up, we identified 616 incident PD cases. A family history of melanoma in a first-degree relative was associated with a higher risk of PD (multivariate relative risk = 1.85; 95% confidence interval: 1.2, 2.8; p = 0.004), after adjusting for smoking, ethnicity, caffeine intake, and other covariates. In contrast, we did not observe significant associations between a family history of colorectal, lung, prostate, or breast cancer and PD risk. Interactions between melanoma family history and age, smoking, or caffeine intake were not significant and subgroup analyses according to these factors generated similar results. CONCLUSIONS: Our findings support the notion that melanoma and Parkinson disease (PD) share common genetic components. The genetic determinants of melanoma could therefore be explored as susceptibility candidate genes for PD.

Surgeons' attitudes and perception of an acute pain service.

OBJECTIVE: To evaluate the attitude and perception of surgeons about postoperative pain management, and an anaesthesiologist-based acute pain service. DESIGN: Questionnaire survey. SETTING: Tertiary university teaching hospital, Hong Kong. PARTICIPANTS: All surgical staff members (specialists and trainees) of the Departments of Surgery, Orthopaedics and Traumatology, and Obstetrics and Gynaecology. MAIN OUTCOME MEASURES: Opinions on postoperative pain management, different pain management modalities, and services provided by the acute pain service. RESULTS: Of the 147 questionnaires, 104 (71%) were returned. The majority (97%) agreed that effective pain control improves patient recovery and 88% believed that anaesthetists should be involved in postoperative pain management. Overall, 85% of the respondents were satisfied with the acute pain service. However, about one third of them wanted to maintain an active role in postoperative pain management and only 54% thought that the acute pain service has a significant impact on patient outcomes. In addition, only 10% of surgeons agreed that patients receiving acute pain service intervention would be discharged earlier. The respondents also thought that, compared to intravenous patient-controlled analgesia, epidural analgesia required more nursing care and was less cost-effective. Areas of the acute pain service warranting improvement included: education of surgeons on postoperative pain and its management (92%), communication (74%), and referral systems (80%). CONCLUSION: The majority of surgeons were satisfied with the acute pain service and agreed that anaesthetists should be involved in postoperative pain management. However, a proportion wanted to maintain an active role in postoperative pain management.

Human endogenous retrovirus-K18 Env as a risk factor in multiple sclerosis.

BackgroundThe human endogenous retrovirus (HERV)-K18 Env is an Epstein-Barr virus (EBV)-associated superantigen. Given the evidence for a role of EBV in the etiology of multiple sclerosis (MS), HERV-K18 Env is a plausible candidate for association with MS.ObjectiveTo assess whether variation in HERV-K18 Env is a risk factor for MS.MethodsWe developed a single nucleotide polymorphism-based genotyping method to determine the distribution of the three alleles of HERV-K18 env. We then conducted a nested case-control study including 207 MS cases and 403 matched controls. Analyses were replicated in an independent series of 909 MS cases and 339 controls.ResultsOverall, there was a significant association between HERV-K18 env genotype and MS risk (chi2 P = 0.03). As compared with K18.2/K18.2 individuals, risk of MS was three fold higher among K18.3/K18.3 individuals (P = 0.03). An increase in MS risk among carriers of the K18.3 allele was also observed in the replication study, but did not reach statistical significance. In pooled analyses, K18.3/K18.3 individuals had a significantly increased risk of MS (relative risks [RR] comparing K18.3/K18.3 vs K18.2/K18.2 = 2.7; 95% confidence interval: 1.1-6.4).ConclusionVariation in EBV-associated superantigen HERV-K18 Env could influence the genetic susceptibility to MS.

Integrating risk factors: HLA-DRB1*1501 and Epstein-Barr virus in multiple sclerosis.

BACKGROUND: Individuals with high levels of antibodies to the Epstein-Barr virus nuclear antigen 1 (EBNA-1) have an increased risk of developing multiple sclerosis (MS), but this association could be confounded by genetic susceptibility. METHODS: We conducted a nested case-control study including 148 women with MS (18 with blood collected before disease onset) and 296 age-matched healthy women to determine whether the human leukocyte antigen (HLA) DRB1*1501 allele (DR15) and anti-Epstein-Barr virus (anti-EBV) antibody titers are independent risk factors for MS. RESULTS: The association between anti-EBNA-1 antibody titers and MS risk was not affected by adjustment for DR15 and was similar in DR15-positive and DR15-negative women. The relative risk of MS among DR15-positive women with elevated (>1:320) anti-EBNA-1 titers was ninefold higher than that of DR15-negative women with low (<1:80) anti-EBNA-1 titers. CONCLUSIONS: Anti-Epstein-Barr virus nuclear antigen 1 (anti-EBNA-1) antibody titers are a risk factor for multiple sclerosis (MS), independently from the DR15 allele. Carriers of the DR15 allele with elevated anti-EBNA-1 antibody titers may have a markedly increased risk of MS.

Analgesic effect of electroacupuncture in postthoracotomy pain: a prospective randomized trial.

BACKGROUND: The role of electroacupuncture in postthoracotomy pain control is uncertain. We conducted a pilot study to evaluate the role of electroacupuncture in the management of early postthoracotomy wound pain. METHODS: A total of 27 patients with operable non-small cell lung carcinoma who received thoracotomy were recruited and randomized to receive either electroacupuncture or sham acupuncture in addition to routine oral analgesics and patient-controlled intravenous analgesia for postoperative pain control. All patients received acupuncture twice daily with visual analog pain score recorded for the first 7 postoperative days. Specific chest acupoints (LI 4, GB 34, GB 36, and TE 8) were targeted. Patient-controlled analgesia was used for the first 3 postoperative days in all patients, and the cumulative dosage used was recorded. RESULTS: Two patients were excluded after randomization because of complications unrelated to acupuncture. Interventions and data collection were completed for the remaining 25 patients (13 in the electroacupuncture group; 12 in the sham acupuncture group). There was a trend for lower visual analog scale pain scores in the electro-acupuncture group between postoperative days 2 and 6, although this did not reach statistical significance. The cumulative dose of patient-controlled analgesia morphine used on postoperative day 2 was significantly lower in the electroacupuncture group (7.5 +/- 5 mg versus 15.6 +/- 12 mg; p < 0.05). Such delay of onset of pain control may be related to the frequency of electroacupuncture used. CONCLUSIONS: Electroacupuncture may reduce narcotic analgesic usage in the early postoperative period. A prospective randomized controlled trial using different electroacupuncture frequency is warranted to verify this benefit.

Randomized, double-blinded, placebo-controlled trial of intravenously administered hyoscine N-butyl bromide in patients undergoing colonoscopy with patient-controlled sedation.

BACKGROUND: A prospective, double-blinded, placebo-controlled randomized trial was conducted to investigate the effect of the antispasmodic hyoscine N-butyl bromide (Buscopan) during colonoscopy. METHODS: A total of 120 patients undergoing colonoscopy were randomized to receive either 40 mg of hyoscine N-butyl bromide (n=60) or normal saline solution (n=60) intravenously as premedication. Colonoscopy was performed under patient-controlled sedation. Outcome measures included cecal intubation and total procedure time, demanded and administered doses of patient-controlled sedation, spasm score, pain score, endoscopist satisfaction score, patient willingness to repeat colonoscopy, and vital signs (blood pressure, pulse rate) during colonoscopy. RESULTS: Mean cecal intubation time in the hyoscine N-butyl bromide group was significantly longer than the control group (12.20 vs. 9.74 minutes; p=0.04; but correction for multiple testing of data removed this significance). The use of hyoscine N-butyl bromide was associated with a significantly lower endoscopist mean satisfaction score (6.47 vs. 7.30; p=0.04; but correction for multiple testing of data removed this significance), higher demanded and administered mean doses of patient-controlled sedation (respectively, 34.80 and 7.25 vs. 24.20 and 5.87; p=0.045; p=0.04, respectively; but correction for multiple testing of data removed these findings of significance), fewer patients willing to repeat colonoscopy (60% vs. 83.9%; p=0.005), and more hemodynamic instability (p<0.001) when compared with the control group. No significant difference was found in the total procedure time, spasm score, or pain score. CONCLUSIONS: Premedication with intravenously administered hyoscine N-butyl bromide impedes colonoscope insertion and causes greater patient discomfort, as well as hemodynamic instability.