BackgroundDuring the COVID-19 pandemic, portable pulse oximeters were issued to some patients to permit home monitoring and alleviate pressure on inpatient wards. Concerns were raised about the accuracy of these devices in some patient groups. This study was conducted in response to these concerns.ObjectivesTo evaluate the performance characteristics of five portable pulse oximeters and their suitability for deployment on home-use pulse oximetry pathways created during the COVID-19 pandemic. This study considered the effects of different device models and patient characteristics on pulse oximeter accuracy, false negative and false positive rate.MethodsA total of 915 oxygen saturation (spO2) measurements, paired with measurements from a hospital-standard pulse oximeter, were taken from 50 patients recruited from respiratory wards and the intensive care unit at an acute hospital in London. The effects of device model and several patient characteristics on bias, false negative and false positive likelihood were evaluated using multiple regression analyses.Results and conclusionsAll five portable pulse oximeters appeared to outperform the standard to which they were manufactured. Device model, patient spO2 and patient skin colour were significant predictors of measurement bias, false positive and false negative rate, with some variation between models. The false positive and false negative rates were 11.2% and 24.5%, respectively, with substantial variation between models.

ABBREVIATIONS LHC Lateral head coverage MDD Minimal detectable difference RMP Reimer's migration percentage AIM To assess the validity of a new index, lateral head coverage (LHC), for describing hip dysplasia in a population of children with cerebral palsy (CP). METHOD LHC is derived from 3D ultrasound assessment. Twenty-two children (15 males, seven females; age 4-15y) with CP undergoing routine hip surveillance were recruited prospectively for the study. Each participant had both a planar radiograph acquired as part of their routine care and a 3D ultrasound assessment within 2 months. Reimer's migration percentage (RMP) and LHC were measured by the same assessor, and the correlation between them calculated using Pearson's correlation coefficient. The repeatability of LHC was investigated with three assessors, analysing each of 10 images three times. Inter-and intraassessor variation was quantified using intraclass correlation coefficients. RESULTS LHC was strongly correlated with RMP (Pearson's correlation coefficient=−0.86, p<0.001). LHC had similar inter-assessor reliability to that reported for RMP (intraclass correlation coefficient=0.97 and intra-assessor intraclass correlation coefficient=0.98). INTERPRETATION This is an initial validation of the use of 3D ultrasound in monitoring hip development in children with CP. LHC is comparable with RMP in estimating hip dysplasia with similar levels of reliability that are reported for RMP.

Aims: Levator ani deficiency has been implicated in anterior pelvic floor pathology but its association with pelvic floor defaecatory dysfunction is less clear. The aim was to examine the relationship of levator ani deficiency with anatomical abnormalities (rectocoele, intussusception, enterocoele, perineal descent) and patient symptoms (bowel, vagina) in patients with pelvic floor defaecatory dysfunction. Methods: The prospective observational case series of 223 women presenting to a tertiary colorectal pelvic floor unit with defaecatory dysfunction. Each underwent assessment with symptom severity and quality of life (QoL) scores, integrated total pelvic floor ultrasound (PFUS) (transvaginal, transperineal) and defaecation proctography (DP). Rectocoele, intussusception, enterocoele and perineal descent were assessed on both. Levator ani deficiency was scored using endovaginal ultrasound (score 0-18; mild [0-6], moderate [>6-12], severe [>12-18]). Results:The proportion of patients with rectocoele, enterocoele, and intussusception increased with increasing levator ani damage (mild, moderate, severe). There was a weakly positive correlation between size of rectocoele and levator ani deficiency. On PFUS, there was a weakly positive correlation between severity of intussusception and enterocoele with levator ani deficiency. On DP, there was a weakly positive correlation between perineal descent and levator ani deficiency. There was no association between bowel symptom and QoL scores and levator ani deficiency. Vaginal symptoms were associated with levator ani deficiency. Conclusions: Anatomical abnormalities which are implicated in pelvic floor defaecatory dysfunction (rectocoele, intussusception, enterocoele, perineal descent) were associated with worsening levator ani deficiency. There was no association between bowel symptoms and levator ani deficiency. Vaginal symptoms were associated with levator ani deficiency.