Ocular microtremor during general anesthesia: results of a multicenter trial using automated signal analysis

Ocular microtremor (OMT) is a fine physiologic tremor of the eye related to neuronal activity in the reticular formation of the brainstem. The frequency of OMT is suppressed by propofol and sevoflurane and predicts the response to command at emergence from anesthesia. Previous studies have relied on post hoc computer analysis of OMT wave forms or on real-time measurements confirmed visually on an oscilloscope. Our overall aim was to evaluate an automated system of OMT signal analysis in a diverse patient population undergoing general anesthesia. In a multicenter trial involving four centers in three countries, we examined the accuracy of OMT to identify the unconscious state and to predict movement in response to airway instrumentation and surgical stimulation. We also tested the effects of neuromuscular blockade and patient position on OMT. We measured OMT continuously by using the closed-eye piezoelectric technique in 214 patients undergoing extracranial surgery with general anesthesia using a variety of anesthetics. OMT decreased at induction in all patients, increased transiently in response to surgical incision or airway instrumentation, and increased at emergence. The frequency of OMT predicted movement in response to laryngeal mask airway insertion and response to command at emergence. Neuromuscular blockade did not affect the frequency of OMT but decreased its amplitude. OMT frequency was unaffected by changes in patient position. We conclude that OMT, measured by an automated signal analysis module, accurately determines the anesthetic state in surgical patients, even during profound neuromuscular blockade and after changes in patient position.     

Factors influencing treatment entry in sex offenders against children

The study examined the psychosocial characteristics of 99 sex offenders against children referred for treatment to a forensic community sex offender programme. The subjects had high levels of substance misuse problems and personality disorder but low rates of Axis I disorder. Subjects accepted for treatment could not be distinguished from those rejected as unsuitable on the Child Sex Questionnaire (CSQ) (Beckett et al., 1994), apart from the question on whether or not subjects believed it was wrong to have sexual contact with children. Substance misuse, antisocial personality disorder and past criminal history did not determine whether subjects were accepted or rejected. Differences in scores on actuarial measures of risk (STATIC-99) were also not significant. Clinicians' ratings of motivation, level of denial and poor social skills were the key factors determining rejection for treatment. Reconviction rates in the treatment group were low (7%) at five-year follow-up.     

Advancing understanding of influences on cervical screening (non)‐participation among younger and older women: A qualitative study using the theoretical domains framework and the COM‐B model

BackgroundEffective screening can prevent cervical cancer, but many women choose not to attend their screening tests.ObjectiveThis study aimed to investigate behavioural influences on cervical screening participation using the Theoretical Domains Framework (TDF) and COM‐B models of behaviour change.DesignA qualitative study and semistructured phone interviews were conducted with women invited for routine screening tests within the national cervical screening programme in Ireland.Setting and ParticipantsForty‐eight women aged 25–65 years were recruited from the national screening register.ResultsSeven core themes were identified that mapped to three COM‐B components and 11 TDF domains: (1) knowledge of cervical cancer and screening, (2) coping with smear tests, (3) competing motivational processes—automatic and reflective, (4) cognitive resources, (5) role of social support, (6) environmental influences and (7) perceputal and practical influences. A range of knowledge about screening, perceived risk of cervical cancer and human papillomavirus infection was evident. Factors that influenced screening behaviours may be hierarchical—some were assigned greater importance than others. Positive screening behaviours were linked to autonomous motivation. Deficits in physical and psychological capability (inadequate coping skills) were barriers to screening, while physical and social opportunity (e.g. healthcare professional ‘champions’) could facilitate participation. Older women raised age‐related issues (e.g. screening no longer necessary) and had more negative attitudes to screening, while younger women identified practical barriers.ConclusionsThis study provides insight into screening participation and will aid development of theoretically informed interventions to increase uptake.Patient or Public ContributionWomen invited for screening tests through the national screening programme were interviewed. A Public & Patient Involvement (PPI) Panel, established to provide input into all CERVIVA research projects, advised the research team on recruitment materials and were given the opportunity to review and comment on the interview topic guide. This panel is made up of six women with various cervical screening histories and experiences.     

Radiopaque drug-eluting embolisation beads as fiducial markers for stereotactic liver radiotherapy

Objective:To determine the feasibility of using radiopaque (RO) beads as direct tumour surrogates for image-guided radiotherapy (IGRT) in patients with liver tumours after transarterial chemoembolisation (TACE).Methods:A novel vandetanib-eluting RO bead was delivered via TACE as part of a first-in-human clinical trial in patients with either hepatocellular carcinoma or liver metastases from colorectal cancer. Following TACE, patients underwent simulated radiotherapy imaging with four-dimensional computed tomography (4D-CT) and cone-beam CT (CBCT) imaging. RO beads were contoured using automated thresholding, and feasibility of matching between the simulated radiotherapy planning dataset (AVE-IP image from 4D data) and CBCT scans assessed. Additional kV, MV, helical CT and CBCT images of RO beads were obtained using an in-house phantom. Stability of RO bead position was assessed by comparing 4D-CT imaging to CT scans taken 6–20 days following TACE.Results:Eight patients were treated and 4D-CT and CBCT images acquired. RO beads were visible on 4D-CT and CBCT images in all cases and matching successfully performed. Differences in centre of mass of RO beads between CBCT and simulated radiotherapy planning scans (AVE-IP dataset) were 2.0 mm mediolaterally, 1.7 mm anteroposteriorally and 3.5 mm craniocaudally. RO beads in the phantom were visible on all imaging modalities assessed. RO bead position remained stable up to 29 days post TACE.Conclusion:RO beads are visible on IGRT imaging modalities, showing minimal artefact. They can be used for on-set matching with CBCT and remain stable over time.Advances in knowledge:The role of RO beads as fiducial markers for stereotactic liver radiotherapy is feasible and warrants further exploration as a combination therapy approach.     

TNFalpha regulates renal COX-2 in the rat thick ascending limb (TAL)

We have examined cyclooxygenase (COX)-2-dependent mechanisms in preglomerular microvessels and the thick ascending limb (TAL). These renal structures are linchpins in the regulation of the renal circulation and extracellular fluid volume. Cytochrome P450 monooxygenases are the principal oxygenases in the TAL segment; however, COX-2 can be expressed in the TAL, as when challenged by angiotensin II. Glucocorticoids also affect the expression and activity of oxygenases in the TAL. Before adrenalectomy, <2% TAL cells expressed COX-2; after, >30% of TAL cells expressed COX-2. Recruitment of COX-2 is initiated in the renal cortex and proceeds to the medulla associated with: (1) COX-2 mRNA accumulation; (2) increased COX-2 expression; and (3) a two-fold increase in PGE2 production by cortical microsomes. These changes were nullified by dexamethasone. COX-2 mRNA, protein expression and PGE2 synthesis in the TAL are also increased in response to increased extracellular Ca2+. The Ca2+ sensing receptor is G-protein coupled and responds to changes in extracellular Ca2+ concentration by increasing protein kinase C activity to produce expression of COX-2. Thus, multiple signaling pathways contribute to COX-2 expression in TAL cells.     

Fetal heart rate response to strenuous maternal exercise: not a predictor of fetal distress

OBJECTIVE: The purpose of this study was to analyze the effects of maternal exercise on fetal heart rate changes to determine prognostic factors for an abnormal trace in labor. STUDY DESIGN: Two hundred fifty-eight primiparous women who were 33 to 38 weeks of gestation with varying levels of activity were recruited. A symptom-limited incremental exercise test was preformed. Cardiotocography was carried out before and after exercise. Data were analyzed with specialized computer software. RESULTS: A strenuous level of exercise was achieved. The most common fetal heart rate response seen was tachycardia. The incidence did not vary with the level of fitness, maternal body mass index, or fetal weight. Male fetuses were more prone to fetal distress. A significantly higher proportion of distressed babies were born to older women (P <.0001). The percentage of abnormal traces was equal in the vaginal and caesarean delivery groups. CONCLUSION: The results showed no correlation among the incidence of fetal distress, the mode of delivery, and the fetal heart rate changes after exercise.     

In Vitro Acoustic Characterization of Three Phospholipid Ultrasound Contrast Agents from 12 to 43 MHz

The acoustic properties of two clinical (Definity, Lantheus Medical Imaging, North Billerica, MA, USA; SonoVue, Bracco S.P.A., Milan, Italy) and one pre-clinical (MicroMarker, untargeted, Bracco, Geneva, Switzerland; VisualSonics, Toronto, ON, Canada) ultrasound contrast agent were characterized using a broadband substitution technique over the ultrasound frequency range 12–43 MHz at 20 ± 1°C. At the same number concentration, the acoustic attenuation and contrast-to-tissue ratio of the three native ultrasound contrast agents are comparable at frequencies below 30 MHz, though their size distributions and encapsulated gases and shells differ. At frequencies above 30 MHz, native MicroMarker has higher attenuation values and contrast-to-tissue ratios than native Definity and SonoVue. Decantation was found to be an effective method to alter the size distribution and concentration of native clinical microbubble populations, enabling further contrast enhancement for specific pre-clinical applications.     

Maternal Obesity and Pre-Pregnancy Folic Acid Supplementation

ObjectiveThe purpose of this nested cohort study was to compare the rate of pre-pregnancy supplementation in obese women with that of women with a normal BMI.MethodsPregnant women were enrolled at their convenience in a large university hospital. Weight and height were measured in the first trimester and BMI categorised.ResultsOf the 288 women, 35.1% were in the normal, 29.5% in the overweight and 35.4% in the obese BMI categories. Only 45.1% (n = 46) of the obese women took pre-pregnancy folic acid compared with 60.4% (n = 61) of women with a normal BMI (p < 0.03). The lower incidence of folic acid supplementation in obese women was associated with an unplanned pregnancy in 36.3% of women compared with 22.8% in the normal BMI category (p < 0.04).ConclusionsObese women should take folate supplements whether they are planning to conceive or not.Key Words: Maternal obesity, Pre-pregnancy folic acid, Body mass index, Unplanned pregnancy