Airway management in the paediatric difficult intubation registry: a propensity score matched analysis of outcomes over time

Background

The Paediatric Difficult Intubation Collaborative identified multiple attempts and persistence with direct laryngoscopy as risk factors for complications in children with difficult tracheal intubations and subsequently engaged in initiatives to reduce repeated attempts and persistence with direct laryngoscopy in children. We hypothesised these efforts would lead to fewer attempts, fewer direct laryngoscopy attempts and decrease complications.

Methods

Paediatric patients less than 18 years of age with difficult direct laryngoscopy were enrolled in the Paediatric Difficult Intubation Registry. We define patients with difficult direct laryngoscopy as those in whom (1) an attending or consultant obtained a Cormack Lehane Grade 3 or 4 view on direct laryngoscopy, (2) limited mouth opening makes direct laryngoscopy impossible, (3) direct laryngoscopy failed in the preceding 6 months, and (4) direct laryngoscopy was deferred due to perceived risk of harm or poor chance of success. We used a 5:1 propensity score match to compare an early cohort from the initial Paediatric Difficult Intubation Registry analysis (August 6, 2012-January 31, 2015, 785 patients, 13 centres) and a current cohort from the Registry (March 4, 2017-March 31, 2023, 3925 patients, 43 centres). The primary outcome was first attempt success rate between cohorts. Success was defined as confirmed endotracheal intubation and assessed by the treating clinician. Secondary outcomes were eventual success rate, number of attempts at intubation, number of attempts with direct laryngoscopy, the incidence of persistence with direct laryngoscopy, use of supplemental oxygen, all complications, and severe complications.

Findings

First-attempt success rate was higher in the current cohort (42% vs 32%, OR 1.5 95% CI 1.3-1.8, p < 0.001). In the current cohort, there were fewer attempts (2.2 current vs 2.7 early, regression coefficient -0.5 95% CI -0.6 to -0.4, p < 0.001), fewer attempts with direct laryngoscopy (0.6 current vs 1.0 early, regression coefficient -0.4 95% CI -0.4 to 0.3, p < 0.001), and reduced persistence with direct laryngoscopy beyond two attempts (7.3% current vs 14.1% early, OR 0.5 95% CI 0.4-0.6, p < 0.001). Overall complication rates were similar between cohorts (19% current vs 20% early). Severe complications decreased to 1.8% in the current cohort from 3.2% in the early cohort (OR 0.55 95% CI 0.35-0.87, p = 0.011). Cardiac arrests decreased to 0.8% in the current cohort from 1.8% in the early cohort. We identified persistence with direct laryngoscopy as a potentially modifiable factor associated with severe complications.

Interpretation

In the current cohort, children with difficult tracheal intubations underwent fewer intubation attempts, fewer attempts with direct laryngoscopy, and had a nearly 50% reduction in severe complications. As persistence with direct laryngoscopy continues to be associated with severe complications, efforts to limit direct laryngoscopy and promote rapid transition to advanced techniques may enhance patient safety.

Funding

None.

Postanesthesia complications in pediatric patients with previous SARS-CoV-2 infection: A cohort study

BACKGROUND

Children with SARS-CoV-2 infection are at increased risk for postanesthesia complications. There is minimal data regarding how long that elevated complication risk persists beyond initial SARS-CoV-2 diagnosis.

AIMS

We investigated postanesthesia complications in children with SARS-CoV-2 infection within 90 days of diagnosis.

METHODS

We completed a single-center, retrospective, case-control study of pediatric patients with confirmed SARS-CoV-2 infection within 90 days undergoing anesthesia between January 3-October 7, 2020. Each SARS-CoV-2 positive patient was matched 1:2 by age and type of procedure with a non-SARS-CoV-2 cohort. The primary outcome was the rate of all postanesthesia complications within 30 days of the procedure, defined as unplanned escalations of care within 48 h, cardiac, respiratory, thrombotic, and hemorrhagic events within 30 days. Secondary outcomes were 30-day mortality and hospital length of stay.

RESULTS

Of the 341 patients included, 114 patients were SARS-CoV-2 positive and 227 were SARS-CoV-2 negative. Patients with a positive test 0-7 days prior to anesthesia had an increased risk difference in all postanesthesia complications within 30 days (19.9, 95% CI [4.7, 35.1], p = .001) and increased risk difference in length of hospital stay (7.8, 95% CI [1.2, 14.4], p < .001). Patients who underwent anesthesia greater than 42 days from SARS-CoV-2 diagnosis had an increased risk difference in cardiac complications within 30 days (4.3, 95% CI [0.9, 10.0], p = .029). There was no increased hospital length of stay among SARS-CoV-2 positive patients diagnosed greater than 8 days before anesthetic. There were no deaths within 30 days of anesthetic.

CONCLUSIONS

Postanesthesia complications are higher in children who undergo anesthesia within 7 days of SARS-CoV-2 diagnosis. Additional cardiac risk may persist beyond the immediate period of initial diagnosis. Larger samples are needed to further evaluate the risk of delayed postanesthesia complications and guide optimal timing of surgery.

Transfusion-associated hyperkalemia in pediatric population: Analyses for risk factors and recommendations

BACKGROUND

Transfusion-associated hyperkalemia (TAH) is a potentially life-threatening complication of red blood cell (RBC) transfusion. Previously, we reported features of RBC transfusions from 35 pediatric patients (TAH group) who had hyperkalemia with RBC transfusion in one-year period at four facilities. In this study, we used multivariate analyses and artificial intelligence to compare the TAH group to newly collected control group (non-TAH group) to identify factors associated with TAH occurrence.

STUDY DESIGN

A review of RBC transfusion with TAH was compared to non-TAH group who did not develop TAH with RBC transfusion at each facility during the same one-year period. The non-TAH group included 12 patients each in 5 age groups. Wilcoxon rank-sum tests recursive feature elimination, least absolute shrinkage, and selection operator (LASSO), and other artificial intelligence techniques were employed to identify the most salient features associated with predicting specific clinical outcomes for TAH occurrence.

RESULTS/FINDINGS

Pre-transfusion creatinine, comorbidities of kidney and/or liver dysfunctions, and total transfused volume within 12 h (tV-12) per kg and per estimated total blood volume (eTBV) showed statistically significant differences between TAH and non-TAH groups. Multivariate analysis revealed the biggest factor in TAH occurrence was tV-12/kg followed by age of RBC units. The thresholds of risks were tV-12/kg of 30 ml/kg, tV-12/eTBV of 30%, and RBC unit age of 7.95 days.

CONCLUSIONS

The study findings suggest that the biggest factor on TAH occurrence is tV-12/kg. More importantly, 30% of eTBV transfusion could cause TAH in patients with multiple comorbidities.

Pediatric Anesthesia Management for Post-Tonsillectomy Bleed: Current Status and Future Directions

After medical stabilization, several techniques are considered for anesthesia in the surgical intervention of post-tonsillectomy bleeding in children. Hypoxia during induction of general anesthesia occurs more frequently than aspiration for this population. While classical (apneic) rapid sequence induction and intubation with cricoid pressure still has a role, controlled rapid sequence induction and intubation that incorporates mask ventilation at low pressure (<12 cm H₂O) before direct laryngoscopy under a deep plane of anesthesia is a viable alternative for cases of slow venous bleeding. Supplemental oxygen delivery during laryngoscopy to permit apneic oxygenation is a future trend in management. While the routine administration of tranexamic acid during tonsillectomy has not been shown to be of benefit, it may have a role in post-tonsillectomy hemorrhage with further study.

Self-reported awareness during general anesthesia in pediatric patients: A study from Wake Up Safe

BACKGROUND

Awareness under general anesthesia occurs rarely, but can result in emotional trauma. Although well-studied in adults, there is a paucity of data on unintentional awareness in children.

AIMS

This case series examines instances of self-reported awareness registered with Wake Up Safe, a patient safety organization that maintains a database of adverse events in pediatric anesthesia.

METHODS

Cases of self-reported intraoperative awareness submitted to Wake Up Safe from January 1, 2010 to May 31, 2020 were reviewed for circumstances, causative factors, and level of harm.

RESULTS

Fourteen cases of self-reported intraoperative awareness out of 555 360 cases in patients aged 5-20 years were noted during the study period. Overall incidence of awareness was 2.52 (95% CI: 1.38-4.23) cases per 100 000 patients, or approximately 1:40 000. Self-reported intraoperative awareness was more frequently associated with cardiac and gastrointestinal endoscopic procedures. Incidence for cardiac procedures was 20.34 (95% CI: 8.18-41.90) cases per 100 000 patients. Incidence for gastrointestinal endoscopic procedures was 7.74 (95% CI: 1.60-22.62) cases per 100 000 patients. Most patients were assessed to have suffered harm.

CONCLUSIONS

Self-reported intraoperative awareness is a rare complication in pediatric patients that has implications for harm. Compared to awareness cases elicited by a questionnaire method, cases of self-reported awareness during general anesthesia may represent those that have a greater impact. A preoperative discussion of intraoperative awareness should be considered for procedures that carry a higher likelihood of awareness in order to mitigate harm.

Serratus Anterior Plane Block as a Primary Anesthetic Technique for Video-Assisted Thoracic Surgery in a Child

Cystic fibrosis (CF) commonly affects those of European descent; however, it can also be found in those of Asian, African, and Caribbean descent. Patients with CF may have significant lung disease, and their perioperative management can be challenging for the anesthesiologist. In this case report, we describe the use of serratus anterior plane block (SAPB) and IV sedation as an alternative to general anesthesia with an endotracheal tube in a patient with CF pulmonary exacerbation presenting to the operating room for a video-assisted thoracic surgery (VATS).

Management of child after traumatic epidural hematoma with pulmonary edema and arrhythmia

We present a case of severe neurogenic pulmonary edema and arrhythmia complicating management of a 7-year-old child with acute epidural hematoma and impending cerebral herniation. The underlying mechanisms for this are discussed as well as management of severe neurogenic pulmonary edema. We emphasize the need to recognize this rare complication early and institute prompt aggressive management.

Open wide: Anesthetic management of a child with Hecht-Beals syndrome

Hecht–Beals syndrome (HBS) is a rare disorder characterized by trismus and deformity of the extremities. The etiology of trismus is unknown; theories suggest invasion of enlarged coronoid processes into the zygomatic bone. Of primary concern is the limited mouth opening and possible difficult airway. Since the syndrome was first described in 1969, there have been several articles in the pediatrics and dental literature but only 6 case reports describing the anesthetic management of these patients. Successful airway approaches have utilized various techniques including blind nasal intubation, fiberoptic intubation, and tracheal tube introducer guidance. In this case report, we discuss a multidisciplinary approach to the anesthetic management of a child with HBS undergoing MRI and outpatient surgery.

Outcomes from wake up safe, the pediatric anesthesia quality improvement initiative

BACKGROUND

Wake Up Safe, a Patient Safety Organization founded by the Society for Pediatric Anesthesia, collects data on serious adverse events along with demographic data from all pediatric patients receiving anesthesia care at participating institutions. This report reviews all events occurring between 2010 and 2015 and focuses on common adverse events that are anesthesia-related.

AIMS

Determine which adverse events were most common from 2010 to 2015 among participating Wake Up Safe institutions. Determine how many anesthesia-related events were deemed to be preventable.

METHODS

This is a descriptive report. The Wake Up Safe registry data were queried on September 29, 2017. Institutions were included if they had complete demographic data and at least 5 adverse events per year reported. At that time, 19 out of 29 institutions had complete demographic data for events from 2010 to 2015. This study describes demographic data and adverse events from these nineteen institutions. Descriptive data were extracted, and event rate was calculated for each adverse event category. In events that were assessed as primarily related to anesthesia, further detailed analysis was performed.

RESULTS

Of all reported adverse events (2544 events), the most common were cardiac arrests (646, 31.6%), respiratory complications (598, 29.2%), and medication events (345, 16.9%). Of all anesthesia-related events (612 events), medication events were the most common (239, 31.9%), followed by respiratory complications (181, 24.1%), and cardiac arrests (139, 18.5%). Overall, 85% of anesthesia-related serious adverse events were deemed somewhat or almost certainly preventable.

CONCLUSIONS

The majority of anesthesia-related serious adverse events reported to the Wake Up Safe database are preventable. Medication events are the most common anesthesia-related adverse events. Innovations aimed at decreasing medication events may be the most impactful.

A Signal Through the Noise: Do Professionalism Concerns Impact the Decision Making of Competence Committees?

PURPOSE

To characterize how professionalism concerns influence individual reviewers' decisions about resident progression using simulated competence committee (CC) reviews.

METHOD

In April 2017, the authors conducted a survey of 25 Royal College of Physicians and Surgeons of Canada emergency medicine residency program directors and senior faculty who were likely to function as members of a CC (or equivalent) at their institution. Participants took a survey with 12 resident portfolios, each containing hypothetical formative and summative assessments. Six portfolios represented residents progressing as expected (PAE) and 6 represented residents not progressing as expected (NPAE). A professionalism variable (PV) was developed for each portfolio. Two counterbalanced surveys were developed in which 6 portfolios contained a PV and 6 portfolios did not (for each PV condition, 3 portfolios represented residents PAE and 3 represented residents NPAE). Participants were asked to make progression decisions based on each portfolio.

RESULTS

Without PVs, the consistency of participants giving scores of 1 or 2 (i.e., little or no need for educational intervention) to residents PAE and to those NPAE was 92% and 10%, respectively. When a PV was added, the consistency decreased by 34% for residents PAE and increased by 4% for those NPAE (P = .01).

CONCLUSIONS

When reviewing a simulated resident portfolio, individual reviewer scores for residents PAE were responsive to the addition of professionalism concerns. Considering this, educators using a CC should have a system to report, collect, and document professionalism issues.

Divide and conquer: A perspective on biochips for single-cell and rare-molecule analysis by next-generation sequencing

Recent advances in biochip technologies that connect next-generation sequencing (NGS) to real-world problems have facilitated breakthroughs in science and medicine. Because biochip technologies are themselves used in sequencing technologies, the main strengths of biochips lie in their scalability and throughput. Through the advantages of biochips, NGS has facilitated groundbreaking scientific discoveries and technical breakthroughs in medicine. However, all current NGS platforms require nucleic acids to be prepared in a certain range of concentrations, making it difficult to analyze biological systems of interest. In particular, many of the most interesting questions in biology and medicine, including single-cell and rare-molecule analysis, require strategic preparation of biological samples in order to be answered. Answering these questions is important because each cell is different and exists in a complex biological system. Therefore, biochip platforms for single-cell or rare-molecule analyses by NGS, which allow convenient preparation of nucleic acids from biological systems, have been developed. Utilizing the advantages of miniaturizing reaction volumes of biological samples, biochip technologies have been applied to diverse fields, from single-cell analysis to liquid biopsy. From this perspective, here, we first review current state-of-the-art biochip technologies, divided into two broad categories: microfluidic- and micromanipulation-based methods. Then, we provide insights into how future biochip systems will aid some of the most important biological and medical applications that require NGS. Based on current and future biochip technologies, we envision that NGS will come ever closer to solving more real-world scientific and medical problems.

STRIDER NZAus: a multicentre randomised controlled trial of sildenafil therapy in early-onset fetal growth restriction

OBJECTIVE

To assess the effect of maternal sildenafil therapy on fetal growth in pregnancies with early-onset fetal growth restriction.

DESIGN

A randomised placebo-controlled trial.

SETTING

Thirteen maternal-fetal medicine units across New Zealand and Australia.

POPULATION

Women with singleton pregnancies affected by fetal growth restriction at 22⁺⁰ to 29⁺⁶ weeks.

METHODS

Women were randomised to oral administration of 25 mg sildenafil citrate or visually matching placebo three times daily until 32⁺⁰ weeks, birth or fetal death (whichever occurred first).

MAIN OUTCOME MEASURES

The primary outcome was the proportion of pregnancies with an increase in fetal growth velocity. Secondary outcomes included live birth, survival to hospital discharge free of major neonatal morbidity and pre-eclampsia.

RESULTS

Sildenafil did not affect the proportion of pregnancies with an increase in fetal growth velocity; 32/61 (52.5%) sildenafil-treated, 39/57 (68.4%) placebo-treated [adjusted odds ratio (OR) 0.49, 95% CI 0.23-1.05] and had no effect on abdominal circumference Z-scores (P = 0.61). Sildenafil use was associated with a lower mean uterine artery pulsatility index after 48 hours of treatment (1.56 versus 1.81; P = 0.02). The live birth rate was 56/63 (88.9%) for sildenafil-treated and 47/59 (79.7%) for placebo-treated (adjusted OR 2.50, 95% CI 0.80-7.79); survival to hospital discharge free of major neonatal morbidity was 42/63 (66.7%) for sildenafil-treated and 33/59 (55.9%) for placebo-treated (adjusted OR 1.93, 95% CI 0.84-4.45); and new-onset pre-eclampsia was 9/51 (17.7%) for sildenafil-treated and 14/55 (25.5%) for placebo-treated (OR 0.67, 95% CI 0.26-1.75).

CONCLUSIONS

Maternal sildenafil use had no effect on fetal growth velocity. Prospectively planned meta-analyses will determine whether sildenafil exerts other effects on maternal and fetal/neonatal wellbeing.

TWEETABLE ABSTRACT

Maternal sildenafil use has no beneficial effect on growth in early-onset FGR, but also no evidence of harm.

Non-thermalization in trapped atomic ion spin chains

Linear arrays of trapped and laser-cooled atomic ions are a versatile platform for studying strongly interacting many-body quantum systems. Effective spins are encoded in long-lived electronic levels of each ion and made to interact through laser-mediated optical dipole forces. The advantages of experiments with cold trapped ions, including high spatio-temporal resolution, decoupling from the external environment and control over the system Hamiltonian, are used to measure quantum effects not always accessible in natural condensed matter samples. In this review, we highlight recent work using trapped ions to explore a variety of non-ergodic phenomena in long-range interacting spin models, effects that are heralded by the memory of out-of-equilibrium initial conditions. We observe long-lived memory in static magnetizations for quenched many-body localization and prethermalization, while memory is preserved in the periodic oscillations of a driven discrete time crystal state.This article is part of the themed issue 'Breakdown of ergodicity in quantum systems: from solids to synthetic matter'.

Overt Visual Attention in Parkinson's Disease

The ability of Parkinsonian (PD) patients to control overt visual attention was investigated, by measuring reaction time to a visual stimulus presented at different distances (1.5 deg, 6 deg, and 12 deg) and directions (left or right) from a central fixation point. Prior to the onset of the target stimulus (a square), a cue stimulus appeared just above the fixation point. With equal probability, the arrow pointed to the left, or to the right, or was ambiguous (with two heads). On 20% of their presentations, the left and right arrows pointed in the direction opposite to where the target was to appear. Subjects were informed that 20% of cues would be misleading, and correcting lenses were used to optimise their visual acuity. In previous work with a similar paradigm, only one target eccentricity was used, and subjects were not refracted, leaving open the possibility that PD subjects had more difficulty in seeing the cues and targets.

The eight PD subjects had longer reaction times than age-matched normal controls (and were relatively slower for the more eccentric targets), but made fewer errors in all conditions. In particular, they were more accurate than the controls on the presentations when the cue was misleading or ambiguous, suggesting that the PD group were ignoring the cue. It seems unlikely that the subjects discriminate the direction of the cues, given the use of optical correction, and they reported seeing the cues. Our data are consistent with those of other workers who have described a similar ‘disengagement of attention’ in PD (Clark et al, 1989 Neuropsychologia27 131 – 140) and attributed it to decreased catecholaminergic activity following destruction of midbrain structures (Wright et al, 1990 Neuropsychologia28 151 – 159).

Hospital Re-Admissions: An Empirical Analysis of Quality Management in Taiwan

This retrospective study uses discharge-level data to analyse and assess the situation of re-admissions within 15 days of discharge, for quality evaluation. The re-admission rate of the study period was 3.22%. Among those re-admission cases, 45.7% patients were re-admitted within five days of discharge, and 33.5% cases returned to hospital six to 10 days after discharge. The average length of stays of re-admissions (9.86 days for previous stay and 8.10 days for re-admitted stay) were both longer than the hospital's overall average (7.63 days) at the same period. Paediatric patients comprised the greatest number of re-admissions. Re-admissions were more likely to have higher percentage of emergency admission. Significant relationships were found between factors for re-admissions and patient characteristics (e.g. age and insurance status), admitted department, and diagnosis. Further investigation and strategies, combined with the application of severity adjustment technique to better monitor and avoid unnecessary re-admissions, need to be developed.

Abstract P1-02-01: Genomic analysis of single cells isolated by a pulse laser retrieval system

Background: Isolating tumor cells of interest and harvesting histologically pure samples is important for genomic studies. Laser capture microdissection (LCM) is an established method to obtain such purified cell populations for various applications including DNA, gene expression, and single cell analyses. However, LCM possesses problems such as limited optical resolution, cell fragmentation from dissection, and adherence of adjacent tissue to the cells which interrupts with single cell isolation from tissue sections. To overcome these obstacles, we developed a high-throughput pulse laser retrieval system which uses a wavelength that minimizes damage to the cellular content and is processed with a sacrificial layer that provides applicable optical resolution. The aim of this study was to evaluate the performance of the pulse laser retrieval system to provide appropriate samples for genomic analysis using breast cancer tissue.

Methods: An indium tin oxide (ITO) coated glass slide was prepared using fresh frozen breast cancer tissue sections of 4㎛ thickness and stained by hematoxylin and eosin. The slide was mounted on the cell isolation machine and imaging was performed with a charge-coupled device camera using a 20× lens. Following identification of the target cells by a pathologist, nano-second pulsed laser (wavelength= 1064nm) was irradiated on the target. Isolated cells were collected in a polymerase chain reaction tube and whole genome amplification (WGA) was carried out using Illustra GenomiPhi V2 DNA Amplification Kit (GE Healthcare Life Sciences, Pittsburgh, PA, USA). Amplified genomic DNA was fragmented and Illumina sequencing libraries were constructed. Sequencing was carried out to generate data with 0.1∼0.2× depth throughout the whole genome for each sample. Copy number variation (CNV) was analyzed by the Variable binning algorithm.

Results: Whole genome amplification was performed using bulk tissue and 10 captured single cells from the same specimen. No difference in amplification coverage was observed between the two samples. A CNV analysis of captured single cells revealed similar CNV profiles with those in a matched bulk tumor. Whole exome sequencing (WES) of captured single cells yielded a variant frequency of 15% at a read depth of 15× and 50M base coverage, compared to 0% at 100× and 50M for WES using bulk tumor and 0.5% at 1200× and 100K for targeted sequencing using bulk tumor. Laser capture was performed for DCIS and stromal cells from the same slide. CNV analysis of the two samples showed minimal CNV in normal stromal cells in contrast to DCIS where multiple CNVs were observed.

Conclusions: Newly developed pulse laser retrieval system is suitable for capturing single cells for genomic analysis of breast cancer. WGA, WES, and CNV analysis was successfully carried out using the captured single cells and showed no difference in profile compared to those performed with bulk tissue. This method may have the potential to replace LCM for certain applications such as single cell analyses.

Citation Format: Lee H-B, Kim S, Lee K-M, Jung Y, Lee AC, Kim J, Bae S, Ryu HS, Yoo T-K, Moon H-G, Noh D-Y, Kwon S, Han W. Genomic analysis of single cells isolated by a pulse laser retrieval system. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-02-01.

Associations between body mass index and maternal weight gain on the delivery of LGA infants in Chinese women with gestational diabetes mellitus

BACKGROUND

Women with gestational diabetes mellitus (GDM) are at increased risk for maternal and fetal complications including delivery of large for gestational age (LGA) infants. Maternal body mass index (BMI) and excessive weight gain during pregnancy are associated with delivery of LGA infants. However, whether maternal BMI and weight gain are associated with LGA infants in women with GDM is unclear.

BASIC PROCEDURES

Data on 1049 pregnant women who developed GDM were collected from a university teaching hospital in China and retrospectively analyzed. Data included maternal BMI, weight gain, incidence of LGA and gestational week at diagnosis.

MAIN FINDINGS

The incidence of LGA infants was significantly associated with maternal BMI (p=0.0002) in women with GDM. The odds of delivery of LGA for obese or overweight pregnant women are 3.8 or 2 times more than normal weight pregnant women. The incidence of LGA infants was also significantly associated with maternal weight gain in women with GDM. The odds ratio of delivery of LGA for pregnant women with excessive weight gain was 3.3 times more than pregnant women with normal weight gain. The effect of weight gain was not significantly different between different maternal BMI.

PRINCIPAL CONCLUSION

The incidence of delivery of LGA infants in Chinese women with GDM who were overweight or obese is higher than Caucasians, Hispanic, and Asian-Americans. The effects of maternal BMI and weight gain on the delivery of LGA infants by women with GDM are additive.

Cochlear ablation effects on amino acid levels in the chinchilla cochlear nucleus

Inner ear damage can lead to hearing disorders, including tinnitus, hyperacusis, and hearing loss. We measured the effects of severe inner ear damage, produced by cochlear ablation, on the levels and distributions of amino acids in the first brain center of the auditory system, the cochlear nucleus. Measurements were also made for its projection pathways and the superior olivary nuclei. Cochlear ablation produces complete degeneration of the auditory nerve, which provides a baseline for interpreting the effects of partial damage to the inner ear, such as that from ototoxic drugs or intense sound. Amino acids play a critical role in neural function, including neurotransmission, neuromodulation, cellular metabolism, and protein construction. They include major neurotransmitters of the brain - glutamate, glycine, and γ-aminobutyrate (GABA) - as well as others closely related to their metabolism and/or functions - aspartate, glutamine, and taurine. Since the effects of inner ear damage develop over time, we measured the changes in amino acid levels at various survival times after cochlear ablation. Glutamate and aspartate levels decreased by 2weeks in the ipsilateral ventral cochlear nucleus and deep layer of the dorsal cochlear nucleus, with the largest decreases in the posteroventral cochlear nucleus (PVCN): 66% for glutamate and 63% for aspartate. Aspartate levels also decreased in the lateral part of the ipsilateral trapezoid body, by as much as 50%, suggesting a transneuronal effect. GABA and glycine levels showed some bilateral decreases, especially in the PVCN. These results may represent the state of amino acid metabolism in the cochlear nucleus of humans after removal of eighth nerve tumors, which may adversely result in destruction of the auditory nerve. Measurement of chemical changes following inner ear damage may increase understanding of the pathogenesis of hearing impairments and enable improvements in their diagnosis and treatment.

Wake Up Safe and root cause analysis: quality improvement in pediatric anesthesia

In 2006, the Quality and Safety Committee of the Society for Pediatric Anesthesia initiated a quality improvement project for the specialty of pediatric anesthesiology that ultimately resulted in the development of Wake Up Safe (WUS), a patient safety organization that maintains a registry of de-identified, serious adverse events. The ultimate goal of WUS is to implement change in processes of care that improve the quality and safety of anesthetic care provided to pediatric patients nationwide. Member institutions of WUS submit data regarding the types and numbers of anesthetics performed and information pertaining to serious adverse events. Before a member institution submits data for any serious adverse event, 3 anesthesiologists who were not involved in the event must analyze the event with a root cause analysis (RCA) to identify the causal factor(s). Because institutions across the country use many different RCA methods, WUS educated its members on RCA methods in an effort to standardize the analysis and evaluate each serious adverse event that is submitted. In this review, we summarize the background and development of this patient safety initiative, describe the standardized RCA method used by its members, demonstrate the use of this RCA method to analyze a serious event that was reported, and discuss the ways WUS plans to use the data to promote safer anesthetic practices for children.

Impact of health systems strengthening on coverage of maternal health services in Rwanda, 2000-2010: a systematic review

From 2000 to 2010, Rwanda implemented comprehensive health sector reforms to strengthen the public health system, with the aim of reducing maternal and newborn deaths in line with Millennium Development Goal 5, among many other improvements in national health. Based on a systematic review of the literature, national policy documents and three Demographic & Health Surveys (2000, 2005 and 2010), this paper describes the reforms and the policies they were based on, and provides data on the extent of Rwanda's progress in expanding the coverage of four key women's health services. Progress took place in 2000-2005 and became more rapid after 2006, mostly in rural areas, when the national facility-based childbirth policy, performance-based financing, and community-based health insurance were scaled up. Between 2006 and 2010, the following increases in coverage took place as compared to 2000-2005, particularly in rural areas, where most poor women live: births with skilled attendance (77% increase vs. 26%), institutional delivery (146% increase vs. 8%), and contraceptive prevalence (351% increase vs. 150%). The primary factors in these improvements were increases in the health workforce and their skills, performance-based financing, community-based health insurance, and better leadership and governance. Further research is needed to determine the impact of these changes on health outcomes in women and children.

P3-12-04: Involved Anterior Margins after Breast Conserving Surgery: Is Re-Excision Required?

Background: Complete tumour excision in breast conserving surgery (BCS) is critical for successful treatment; involved circumferential resection margins are associated with increased disease recurrence. However, the importance of an involved anterior margin is less clear. The purpose of this study was to audit an aggressive approach to involved anterior margins and hence assess whether anterior margin re-excision yields clinical benefit.

Material and Methods: A retrospective case note and pathology review was performed for all patients who underwent BCS between 2006 and 2010 through a single cancer centre. An involved margin was defined as &lt;1mm clearance of invasive or in situ breast cancer. Results: 1667 patients underwent BCS for invasive and/or in-situ disease, of whom 114 (6.8%) underwent re-excision, most commonly for mixed invasive and in-situ pathology. The annual re-excision rate rose significantly (p&lt;0.001), with no change in whole tumour diameter, specimen weight or specimen volume. A total of 170 involved margins were identified: most commonly the anterior margin (59 margins, 30.6%) followed by the posterior (39 22.9%) or inferior (31, 18.3%) margin. Patients with anterior margin involvement were more likely to have grade 3 invasive disease (p=0.0323) but less likely to have residual disease found at re-excision (2/49 vs. 32/101 margins, p=0.0033); there were no differences when in-situ characteristics were compared.

Conclusions: Re-excision of involved anterior margins rarely excises residual disease and may be unnecessary. Multidisciplinary teams should consider whether further therapy for an involved anterior margin is required on a patient by patient basis.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-12-04.

Attributes of response in depressed patients switched to treatment with duloxetine

BACKGROUND

This study was designed to assess clinical and functional outcomes associated with switching to duloxetine treatment in patients with major depressive disorder (MDD) experiencing emotional and painful physical symptoms in their current episode.

METHODS

In this 8-week, multinational, multicentre, single-arm, open-label clinical trial, 242 MDD patients were switched to duloxetine 60 mg/day after selective serotonin reuptake inhibitor (SSRI) or serotonin and norepinephrine reuptake inhibitor (SNRI) treatment. The primary analysis compared mean change from baseline in Brief Pain Inventory-Modified Short Form (BPI-SF) interference score between initial responders [≥ 50% reduction from baseline on the 17-item Hamilton Depression Rating Scale (HAMD(17)) Maier subscale] and initial non-responders after 4 weeks. Initial responders continued with duloxetine 60 mg/day. Initial non-responders received duloxetine 120 mg/day for the remaining 4 weeks. Depression, pain, anxiety and functional outcomes were also compared after 8 weeks.

RESULTS

BPI-SF interference decreased from baseline in initial responders (n = 108) and initial non-responders (n = 85) after 4 weeks of duloxetine treatment, with greater reductions in initial responders [BPI-SF mean difference in reduction: 1.01 (95% CI 0.42-1.61); p < 0.001]. Reductions in pain interference favouring initial responders were also apparent after 8 weeks [0.68 (95% CI: 0.03-1.33); p = 0.042]. Depression, pain, anxiety and function improved over 8 weeks across patient groups.

CONCLUSIONS

Elements of core mood and pain are important residual symptoms following poor treatment response in MDD. Early improvement in these symptoms after switching to duloxetine indicated an increased chance of functional recovery.

Pharmacological effects of cannabinoids on the Caco-2 cell culture model of intestinal permeability

Activation of cannabinoid receptors decreases emesis, inflammation, gastric acid secretion, and intestinal motility. However, the effects of cannabinoids on intestinal permeability have not yet been established. The aim of the present study is to examine the effects of cannabinoids on intestinal permeability in an in vitro model. Caco-2 cells were grown until fully confluent on inserts in 12-well plates. Transepithelial electrical resistance (TEER) measurements were made as a measure of permeability. EDTA (50 μM) was applied to reversibly increase permeability (reduce TEER). The effects of cannabinoids on permeability in combination with EDTA, or alone, were assessed. Potential target sites of action were investigated using antagonists of the cannabinoid (CB)(1) receptor, CB(2) receptor, transient receptor potential vanilloid subtype 1 (TRPV1), peroxisome proliferator-activated receptor (PPAR)γ, PPARα, and a proposed cannabinoid receptor. When applied to the apical or basolateral membrane of Caco-2 cells, Δ(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD) enhanced the speed of recovery of EDTA-induced increased permeability. This effect was sensitive to cannabinoid CB(1) receptor antagonism only. Apical application of endocannabinoids caused increased permeability, sensitive to cannabinoid CB(1) receptor antagonism. By contrast, when endocannabinoids were applied basolaterally, they enhanced the recovery of EDTA-induced increased permeability, and this involved additional activation of TRPV1. All cannabinoids tested increased the mRNA of the tight junction protein zona occludens-1, but only endocannabinoids also decreased the mRNA of claudin-1. These findings suggest that endocannabinoids may play a role in modulating intestinal permeability and that plant-derived cannabinoids, such as THC and CBD, may have therapeutic potential in conditions associated with abnormally permeable intestinal epithelium.

Stat3-dependent acute Rantes production in vascular smooth muscle cells modulates inflammation following arterial injury in mice

Inflammation is a key component of arterial injury, with VSMC proliferation and neointimal formation serving as the final outcomes of this process. However, the acute events transpiring immediately after arterial injury that establish the blueprint for this inflammatory program are largely unknown. We therefore studied these events in mice and found that immediately following arterial injury, medial VSMCs upregulated Rantes in an acute manner dependent on Stat3 and NF-kappaB (p65 subunit). This led to early T cell and macrophage recruitment, processes also under the regulation of the cyclin-dependent kinase inhibitor p21Cip1. Unique to VSMCs, Rantes production was initiated by Tnf-alpha, but not by Il-6/gp130. This Rantes production was dependent on the binding of a p65/Stat3 complex to NF-kappaB-binding sites within the Rantes promoter, with shRNA knockdown of either Stat3 or p65 markedly attenuating Rantes production. In vivo, acute NF-kappaB and Stat3 activation in medial VSMCs was identified, with acute Rantes production after injury substantially reduced in Tnfa-/- mice compared with controls. Finally, we generated mice with SMC-specific conditional Stat3 deficiency and confirmed the Stat3 dependence of acute Rantes production by VSMCs. Together, these observations unify inflammatory events after vascular injury, demonstrating that VSMCs orchestrate the arterial inflammatory response program via acute Rantes production and subsequent inflammatory cell recruitment.

Bruises, blood coagulation tests and the battered child syndrome

Cutaneous bruises are a common symptom and a sign of injury and blood coagulation disorders in childhood. A carefully-taken history, coupled with a thorough physical examination, would lead to the diagnosis, or guide the clinician to the necessary laboratory investigations. Most children suffering from non-accidental injury can have their diagnosis established on clinical grounds alone and do not require laboratory investigation. An initial screening with full blood counts, prothrombin time and activated partial thromboplastin time will be adequate in most cases if laboratory investigation is indicated, but the clinician must be aware of the limitations of these tests. The finding of an abnormal coagulation test does not exclude child abuse as it can be a consequence of maltreatment, or the two conditions may coexist. Whenever necessary, the opinion of a haematologist should be sought in order to obtain an accurate diagnosis, which is essential for subsequent management and the prevention of further injury in the case of child abuse.

The selective use of magnetic resonance cholangiopancreatography in the imaging of the axial biliary tree in patients with acute gallstone pancreatitis

BACKGROUND

Magnetic resonance cholangiopancreatography (MRCP) is an emerging modality in the management of acute gallstone pancreatitis (AGP). The aim of this study was to assess the impact following the introduction of MRCP in the management of AGP in a tertiary referral unit.

METHODS

Patients presenting with AGP from January 2002 to December 2004 were reviewed to assess the impact of the introduction of MRCP in June 2003. The indication for MRCP was suspected common bile duct (CBD) stones in the absence of biliary sepsis. Definitive treatment for AGP was laparoscopic cholecystectomy, with endoscopic retrograde cholangiopancreatography (ERCP) and sphincterotomy reserved for patients unfit for cholecystectomy and those with biliary sepsis.

RESULTS

249 patients were identified of whom 36 (14.5%) underwent ERCP and sphincterotomy as definitive treatment. 96 patients with a non-dilated CBD and normal or resolving liver function tests proceeded to laparosocopic cholecystectomy and intraoperative cholangiogram (IOC), 8 (8.5%) of whom had CBD stones intraoperatively. Eleven patients underwent cholecystectomy during pancreatic necrosectomy. Of those undergoing preoperative diagnostic biliary tract imaging, ERCP was undertaken in 57 patients and MRCP in 49 patients. There was no significant difference in serum bilirubin levels [ERCP 43 mmol/l (18-204) vs. MRCP 39 mmol/l (24-180), p = NS] or the proportion of patients with CBD stones [ERCP 10 (17.5%) vs. MRCP 7 (14.2%), p = NS] between the two groups. Patients who underwent MRCP had a shorter median hospital stay [MRCP 5 days (range: 3-14) vs. ERCP 9 days (range: 4-20), p < 0.01] and higher rate of cholecystectomy during the index admission (MRCP 83.3% vs. ERCP 67.2%, p < 0.05). There was a high degree of correlation between preoperative MRCP results and findings of subsequent IOC or therapeutic ERCP (area under ROC curve: 0.94).

CONCLUSIONS

MRCP is an accurate modality for imaging the axial biliary tree in patients with AGP. Selective use of MRCP reduces the need for ERCP and results in shorter hospital stay. and IAP.

Prognostic factors in patients undergoing surgery for severe necrotizing pancreatitis

Pancreatic necrosectomy remains an important treatment modality for the management of infected pancreatic necrosis but is associated with significant mortality. The aim of this study was to identify factors associated with mortality following pancreatic necrosectomy. Patients who underwent pancreatic necrosectomy from January 1995 to December 2004 were reviewed. The association between admission, preoperative and postoperative variables, and mortality was assessed using logistic regression analysis. A total of 1248 patients presented with acute pancreatitis, of whom 94 (7.5%) underwent pancreatic necrosectomy (51 men, 43 women). The preoperative median Acute Physiology, Age, and Chronic Health Evaluation (APACHE II) score was 9 (range 2-19). The median cumulative organ dysfunction score was 2 (0-9) preoperatively and 4 (1-11) postoperatively. In all, 23 patients (24.5%) died. Those who died were older than the survivors; the ages (median and range) were 69 years (40-80 years) versus 52 years (19-79 years) (p < 0.05). They also had higher admission APACHE II scores (median and range): 14 (12-19) versus 9 (2-22) (p < 0.001). There were significant associations between preoperative (p < 0.01) and postoperative (p < 0.01) Marshall scores and mortality following pancreatic necrosectomy. The presence of the systemic inflammatory response syndrome (SIRS) during the first 48 hours (p < 0.01) and the time between presentation and necrosectomy (p < 0.01) were independent predictors of survival. Pancreatic necrosectomy is associated with higher mortality in patients with increased APACHE II scores, early persistent SIRS, and unresolved multiorgan dysfunction. Necrosectomy is associated with poorer outcome when performed within 2 weeks of presentation.

A Comparison of knowledge about asthma between Asians and non-Asians at two pediatric clinics

Little is known about the relative knowledge of asthma in recent immigrant Asian populations in the United States (US). To comparatively assess asthma knowledge for Asian and non-Asian populations, 333 parents and children were surveyed at two geographically close urban clinics that had a large percentage of Asian patients, most of whom were Chinese. The Asian respondents scored lower compared to the non-Asian respondents on 4 of the 6 knowledge questions (p < 0.001). Subcategories of non-Asians (white, African-American, Hispanic) were more similar to each other than they were to Asians. In multivariate analysis we found that SES (measured as parental occupation) and being Asian were independent predictors of less asthma knowledge. Having family members with asthma did not improve knowledge scores. A single focus group of Cantonese-speaking parents of asthmatic children suggested that a combination of cultural factors and lack of knowledge contribute to lower knowledge scores in this Asian population. Asthma education programs need to be developed, tailored to recent Asian immigrants and tested for efficacy.

Native and foreign born as predictors of pediatric asthma in an Asian immigrant population: a cross sectional survey

BACKGROUND

Asthma prevalence is lower in less developed countries and among some recent immigrant populations in the US, but the reasons for this are not clear. One possibility is that early childhood infections are protective against asthma.

METHODS

We surveyed Asian immigrant children (n = 204; age 4-18) to assess the relationship between asthma and native or foreign place of birth. We included questions about environmental exposures, demographic variables and family history of asthma to test whether they might explain effects of place of birth on asthma.

RESULTS

The native and foreign born groups were similar in most respects. Analysis of association with diagnosed asthma for all ages together resulted in two logistic regression models. Both retained born in the US (ORs were 3.2 and 4.3; p < 0.01) and family history of asthma (ORs were 6.4 and 7.2; p < 0.001). One model retained living near heavy motor traffic (OR = 2.6; p = 0.012). The other retained language (OR = 3.2; p = 0.003). However, for older children (11-18 years of age) being born in the US lost some of its predictive power.

CONCLUSION

Our findings are consistent with early childhood infections that are prevalent outside the US protecting against asthma.

Identification of susceptibility and protective major histocompatibility complex haplotypes in canine diabetes mellitus

Diabetes mellitus occurs spontaneously in dogs, which is believed to have an autoimmune component and to be a model of human latent autoimmune diabetes of adults (LADA). Some dog breeds (e.g. Samoyed) are particularly predisposed, whereas others (e.g. Boxer) are highly resistant. With the completion of the Dog Genome Assembly, comparative genomic studies of complex diseases in dogs, including diabetes, could provide an important investigative approach into such disorders. Type 1 diabetes in humans is strongly associated with major histocompatibility complex (MHC) class II polymorphisms. We have investigated whether canine dog leucocyte antigen (DLA) class II haplotypes are associated with diabetes. DNA from 460 cases and 1047 controls were genotyped for DLA-DRB1, DLA-DQA1 and DLA-DQB1 using sequence-based typing. Three DLA haplotypes, DRB1*009/DQA1*001/DQB1*008, DRB1*015/DQA1*0061/DQB1*023 and DRB1*002/DQA1*009/DQB1*001, were found at significantly increased frequency in cases with diabetes compared with controls. One DLA-DQ haplotype, DQA1*004/DQB1*013, was significantly reduced in cases with diabetes. Further analysis showed that DQA1 alleles carrying arginine at codon 55 of DQA1 were increased in dogs with diabetes. To our knowledge, this is the first report of a comparative study of MHC and diabetes in a non-rodent species. Since no laboratory model of LADA exists and dogs and humans share similar environments, further research into canine diabetes is warranted.

Spectral characterization of yeast cells with an epitaxy-based UV-Vis optical sensor

The optical spectra of yeast cells in phosphate buffer saline (PBS) were analyzed with an optical UV-vis sensor based on a shallow p(+)n junction realized in a low doped n-type epitaxial silicon layer grown on a strongly doped n(+) substrate. The presence of the n/n(+) interface allows a significantly enhanced sensitivity, due to an increased collection of carriers photogenerated both by short and large wavelengths in the range 250...800 nm. In our experiments the optical absorption of yeast cells was investigated in the wavelength range 250...500 nm as a function of the cells concentration in PBS in the range of 6 x 10(6)-2 x 10(8) cells/ml. The main absorption peaks were found at 310, 350, 400 and 427 nm, respectively. A significant red shift of the wide absorption band at 427 nm has been observed when increasing cell concentration. This red shift behaviour was nonlinear, with saturation observed for yeast concentrations larger than 5 x 10(7) cells/ml. The half-peak bandwidth of this peak also showed a most significant nonlinear variation. These findings suggest that monitoring the parameters of the absorption band at 427 nm versus cells concentration could be used, e.g. using a dedicated integrated spectrometric microsystem, for fast quantitative measurements of yeast cell concentrations in various bio-samples, with possible applications in the food industry.

Intraoperative touch imprint cytology for the diagnosis of sentinel lymph node metastases in breast cancer

Background

Intraoperative detection of sentinel lymph node (SLN) metastases enables the surgeon to take an immediate decision to proceed to completion axillary lymph node dissection (ALND). The aim of this study was to determine the accuracy of touch imprint cytology (TIC) for the diagnosis of SLN metastases in sentinel nodes from women with breast cancer.

Methods

Touch imprints from 235 sentinel nodes in 133 women with breast cancer were diagnosed by cytopathology and compared with definitive histopathology results. After a feasibility study, a real-time study was performed with the surgeon proceeding to ALND based on the TIC diagnosis. The clinical opinion of the operating surgeon as to whether the SLN appeared to contain metastases was recorded, as was the time taken for the result to be available.

Results

TIC detected metastases with a sensitivity of 81·1 per cent and a specificity of 100 per cent. False-negative TIC diagnoses were associated with micrometastases and lobular carcinoma. The majority of false-negative diagnoses were due to sampling rather than interpretation errors. Clinical assessment of sentinel nodes had a sensitivity of 64·3 per cent and a specificity of 87·6 per cent.

Conclusion

TIC is feasible and enables the rapid diagnosis of SLN metastases with an acceptable accuracy for clinical use in ductal carcinoma of the breast.

Electromechanical effects on tether formation from lipid membranes: a theoretical analysis

The material properties of biomembranes can be measured by forming a tether, a thin bilayer tube that extends from the membrane surface. Recent experiments have demonstrated that the force required to maintain a tether is sensitive to the transmembrane potential. As a first approach towards understanding this phenomenon, a thermodynamic analysis of the influence of electrical fields on tether formation from an aspirated lipid vesicle is developed. The analysis considers contributions from Maxwell stresses as well as two forms of electromechanical coupling: coupling between the electric field and curvature strain (flexoelectric coupling) and between the electric field and areal strain (piezoelectric coupling). Predictions of equilibrium tether conformations are obtained numerically. For expected values of the dimensionless coupling parameters, flexoelectric coupling alters the force required to form a tether of a given length, while piezoelectric coupling and Maxwell forces do not greatly change the force versus tether length behavior. The results of this analysis indicate that tether experiments have the potential to characterize electromechanical coupling in both synthetic and cellular membranes.

Detection of allelic variants of the canine IGHA gene by fluorescence resonance energy transfer melting temperature examination

The fluorescence resonance energy transfer (FRET) dual hybridisation probe system has been used for the detection of the accumulation of target DNA during real-time PCR and for the identification of nucleotide polymorphisms through examination of melt curves. This system involves the use of two oligonucleotide probes which are located close to each other and are complementary to an internal segment of a target DNA of interest. Four allelic variants of the gene encoding the hinge region of the immunoglobulin A (IgA) heavy chain (IGHA) have been so far identified in the dog and this variability is due to a combination of single nucleotide polymorphisms and insertion/deletion of nucleic acid motifs. An individual dog may be homozygous or heterozygous for these allelic variants. The purpose of this study was to develop a FRET-based dual probe melting temperature assay to identify the alleles present within an individual dog and to use this assay to determine the frequency of the four allelic variants in different breeds within the canine population. A single pair of oligonucleotide probes were designed that were able to discriminate between the four allelic variants in both homozygous and heterozygous individuals. The genotype of 96 DNA samples obtained from various purebreeds of dogs was determined using this FRET assay. The frequency of each allele differed between the breed groups. The results of this study indicate that it is possible to distinguish relatively complex gene polymorphisms using a single set of oligonucleotide probes. Furthermore, any future comparison of IGHA genotypes between normal and diseased dog populations must take into account the breed variation in allelic frequency.

Screening for asthma in Cantonese-speaking immigrant children

BACKGROUND

Asthma prevalence among Chinese immigrant children is poorly understood and attempts to screen these children have produced varied outcomes. We sought to learn how to improve screening for asthma in Chinese immigrant children.

METHODS

Children (n = 152) were administered the Brief Pediatric Asthma Screen in either Cantonese or English, they then viewed and reacted to a video showing people wheezing and subsequently took a pulmonary function test.

RESULTS

The diagnosed asthma prevalence for our study population was 27.0%, with another 5.3% having possible undiagnosed asthma. Very few children had spirometry findings below normal. In multivariate analysis, being native born (p = 0.002) and having a family history of asthma (p = 0.003) were statistically associated with diagnosis of asthma. After viewing the video, 35.6% of respondents indicated that the images differed from their conception of wheezing. Of four translations of the word "wheeze" no single word was chosen by a majority.

CONCLUSION

Our findings suggest that asthma diagnoses are higher for Chinese children who were born in the US suggesting that desegregation of data might reveal at risk subpopulations. Care needs to be taken when diagnosing asthma for Cantonese speakers because of the centrality of the word wheeze and the challenges of translation.

Hemispace differences in the visual perception of size in left hemiParkinson's disease

The visual perception of size in different regions of external space was studied in Parkinson's disease (PD). A group of patients with worse left-sided symptoms (LPD) was compared with a group with worse right-sided symptoms (RPD) and with a group of age-matched controls on judgements of the relative height or width of two rectangles presented in different regions of external space. The relevant dimension of one rectangle (the 'standard') was held constant, while that of the other (the 'variable') was varied in a method of constant stimuli. The point of subjective equality (PSE) of rectangle width or height was obtained by probit analysis as the mean of the resulting psychometric function. When the standard was in left space, the PSE of the LPD group occurred when the variable was smaller, and when the standard was in right space, when the variable was larger. Similarly, when the standard rectangle was presented in upper space, and the variable in lower space, the PSE occurred when the variable was smaller, an effect which was similar in both left and right spaces. In all these experiments, the PSEs for both the controls and the RPD group did not differ significantly, and were close to a physical match, and the slopes of the psychometric functions were steeper in the controls than the patients, though not significantly so. The data suggest that objects appear smaller in the left and upper visual spaces in LPD, probably because of right hemisphere impairment.

Episodic memory meets working memory in the frontal lobe: functional neuroimaging studies of encoding and retrieval

Recent functional-neuroimaging studies have provided a wealth of new information suggesting that regions of the prefrontal cortex play a role in episodic memory encoding and retrieval. This review seeks to evaluate the results of these studies in the context of one general model that has proposed that the left prefrontal cortex is preferentially involved in episodic memory encoding, whereas the right prefrontal cortex is preferentially involved in episodic memory retrieval, irrespective of the type (e.g., modality) of information being remembered. The origins of this framework are considered in some detail and then all relevant functional-neuroimaging studies are critically reviewed. The results of this review fail to provide support for the functional-asymmetry model, suggesting instead that episodic memory encoding and retrieval may actually involve similar regions of the lateral prefrontal cortex when all factors relating to the type of stimulus material (i.e., modality), are appropriately controlled.

Ventral hernia repair: a study of current practice

Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias. Clinical trials are required to establish the best method of repair for this common condition.

Pain Assessment for the Dementing Elderly (PADE): reliability and validity of a new measure

OBJECTIVES

To establish the reliability and validity of a measure to assess pain in individuals with advanced dementia.

DESIGN

Sixty-five residents of long-term care facilities were assessed using a new rating tool, the Pain Assessment for the Dementing Elderly (PADE), in two separate studies: (1) Residents were assessed simultaneously by two different raters, at Time 1 and 2, to establish interrater reliability, stability, and internal consistency. (2) Validity was established by assessing the correlation between an agitation scale and the PADE; by comparing groups with pain as a significant clinical factor (as assessed by an independent rater) versus not a significant factor, and by assessing individuals receiving versus not receiving psychoactive medications.

SETTING

Four different long-term care facilities, three skilled nursing facilities, and a locked dementia assisted-living facility.

PARTICIPANTS

Twenty-five residents of long-term care facilities with advanced levels of dementia in Study 1, and 40 residents with similar level of dementia in Study 2; 42% of the total sample were rated as having significant painful conditions.

MEASUREMENTS

For Study 1, the PADE was administered; for Study 2, the PADE and the Cohen-Mansfield Agitation Inventory (CMAI) were administered.

RESULTS

Reliability coefficients were adequate (interrater = 0.54-0.95; stability = 0.70-0.98; and internal consistency = 0.24-0.88). Validity coefficients were likewise encouraging, with the PADE demonstrating the expected relationship with a measure of agitation. The PADE also differentiated between groups that were independently judged to suffer clinically problematic pain versus those who were not.

CONCLUSION

The PADE is a reliable and valid tool to assess pain in dementing elderly residents of long-term care facilities.

Dopamine and the representation of the upper visual field: evidence from vertical bisection errors in unilateral Parkinson's disease

It has been suggested that dopamine is an important neurotransmitter in the brain mechanisms which represent the upper visual field. This idea was tested with a vertical line bisection task in unilateral Parkinson's disease. Stimuli of a range of lengths were presented on a large screen in three positions (left, centre and right) and at two viewing distances (0.6 and 1.5m). The patients, who were compared with a group of normal age-matched controls, comprised 16 sufferers from predominantly unilateral disease, 8 with more severe left-sided symptoms (LPD) and 8 with more severe right-sided symptoms (RPD). The LPD group consistently set the bisecting cursor below the midpoint of the stimulus lines, and their bisection error became larger as the length of the line increased. In contrast, the controls set the cursor above the midpoint of the line, an error which also increased with line length. The settings of the RPD group were similar to those of the controls. The results suggest altitudinal neglect in left unilateral PD, and support the hypothesis of dopaminergic involvement in the coding of upper visual space, with the proviso that the perceptual component of this involves the right hemisphere in humans.

Role of synaptic metabotropic glutamate receptors in epileptiform discharges in hippocampal slices

Application of group I metabotropic glutamate receptor (mGluR) agonists elicits seizure discharges in vivo and prolonged ictal-like activity in in vitro brain slices. In this study we examined 1) if group I mGluRs are activated by synaptically released glutamate during epileptiform discharges induced by convulsants in hippocampal slices and, if so, 2) whether the synaptically activated mGluRs contribute to the pattern of the epileptiform discharges. The GABA(A) receptor antagonist bicuculline (50 microM) was applied to induce short synchronized bursts of approximately 250 ms in mouse hippocampal slices. Addition of 4-aminopyridine (4-AP; 100 microM) prolonged these bursts to 0.7-2 s. The mGluR1 antagonist (S)-(+)-alpha-amino-4-carboxy-2-methylbenzeneacetic acid (LY 367385; 25-100 microM) and the mGluR5 antagonist 2-methyl-6-(phenylethynyl)pyridine (MPEP; 10-50 microM), applied separately, significantly reduced the duration of the synchronized discharges. The effects of these antagonists were additive when applied together, suggesting that mGluR1 and mGluR5 exert independent actions on the epileptiform bursts. In phospholipase C beta1 (PLCbeta1) knockout mice, bicuculline and 4-AP elicited prolonged synchronized discharges of comparable duration as those observed in slices from wild-type littermates. Furthermore, mGluR1 and mGluR5 antagonists reduced the duration of the epileptiform discharges to the same extent as they did in the wild-type preparations. The results suggest that mGluR1 and mGluR5 are activated synaptically during prolonged epileptiform discharges induced by bicuculline and 4-AP. Synaptic activation of these receptors extended the duration of synchronized discharges. In addition, the data indicate that the synaptic effects of the group I mGluRs on the duration of epileptiform discharges were mediated by a PLCbeta1-independent mechanism.

Late degeneration in rabbit tissues after irradiation by heavy ions

In 1974, using the rabbit as a model, we began long-term experiments designed to help in the evaluation of the hazards to man from extended exposure to heavy ions in space. Such exposure would occur, for example, during the construction of solar power stations in stationary orbits or on round trips to Mars. Our experiments with 400 MeV/nucleon Ne ions and 570 MeV/nucleon Ar ions have shown that true late effects of a degenerative nature are manifested only years after irradiation. At the appropriate doses (the high end of the experimental dose range), the magnitudes of the late effects are comparable with those encountered in human patients given radiation therapy with neutrons. Such comparisons show that the rabbit experiments are applicable to man. Given that basis, the results from the low end of the experimental dose range lead to the conclusion that astronauts subjected to the radiation fluxes anticipated during flights of the above duration could experience late radiation effects one or more decades after exposure. Late degenerative changes will occur in tissues of the central nervous system, terminally differentiating systems and stem cell populations. The studies also indicate that individual tissues may be "prematurely aged" by radiation in the sense that the "life spans" of those tissues can be decreased without the appearance of malignancies.

The role of dynamic imaging in sentinel lymph node biopsy in breast cancer

The aim of this study was to evaluate the role of dynamic imaging in sentinel lymph node (SLN) biopsy in breast cancer. Patients with T1/T2, N0 invasive breast cancer underwent SLN localisation using intra-dermal injection of 15 MBq of 99mTc-nanocolloid. Gamma camera anterior-oblique dynamic imaging commenced simultaneously with tracer administration for 45 min, and was followed by anterior and lateral static imaging. Dynamic imaging data was reformatted into image files of different time-frames. Patterns of uptake were analysed using the sequences of dynamic frames and time-activity curve (TAC). SLN localisation was successful in 70/73 studies (96%) in 72 patients. Imaging information was present within the first 15 min of dynamic imaging in 67/70 studies (96%). Critical analysis of dynamic data helped to differentiate true SLN from secondary echelon nodes in eight studies and transient foci of radioactivity in six studies. In 17 studies, SLN contained metastatic disease. The detection of SLN metastasis was independent from the use of dynamic imaging. Dynamic imaging improves the interpretation of preoperative SLN imaging for breast cancer, but does not contribute significantly to the successful detection of SLN. Hence, preoperative dynamic imaging is not necessary in SLN biopsy for breast cancer.