Observational study of peripheral skin temperature changes following spinal anaesthesia for caesarean birth.

BACKGROUND: Spinal anaesthesia is widely used in obstetric anaesthesia practice but there is limited knowledge about the development of sympathetic blockade following spinal anaesthesia for caesarean birth. This study investigated the characteristics of sympathetic blockade by measuring peripheral skin temperature changes in the feet of patients given spinal anaesthesia for elective caesarean birth. METHODS: A prospective observational study was conducted involving 60 eligible parturients scheduled for elective caesarean birth with spinal anaesthesia. Skin temperature probes were attached to the dorsum of both feet, and temperature measurements were recorded every minute. The dose of spinal anaesthesia given, and other relevant patient data, were collected. RESULTS: All participants had successful spinal anaesthesia. Following spinal anaesthesia, a sustained rise in skin temperature of both feet was observed, indicating the presence of sympathetic blockade. The maximum rate of temperature increase occurred between 6 and 15 min after the intrathecal injection and plateaued from 22 min after the injection. Control participants did not show any changes in foot temperature. CONCLUSIONS: This study demonstrates that successful spinal anaesthesia for caesarean birth results in a consistent and reliable rise in skin temperature of the feet that is evident after six minutes from intrathecal injection. The observed temperature changes provide indirect objective evidence of bilateral sympathetic blockade. Measurement of feet skin temperatures may serve as an additional objective indicator of successful spinal anaesthesia, along with tests of lower limb motor block and sensory block height. These findings contribute to the understanding of sympathetic blockade during spinal anaesthesia.

A national cohort study to investigate the association between ethnicity and the provision of care in obstetric anaesthesia in England between 2011 and 2021.

There is evidence that ethnic inequalities exist in maternity care in the UK, but those specifically in relation to UK obstetric anaesthetic care have not been investigated before. Using routine national maternity data for England (Hospital Episode Statistics Admitted Patient Care) collected between March 2011 and February 2021, we investigated ethnic differences in obstetric anaesthetic care. Anaesthetic care was identified using OPCS classification of interventions and procedures codes. Ethnic groups were coded according to the hospital episode statistics classifications. Multivariable negative binominal regression was used to model the relationship between ethnicity and obstetric anaesthesia (general and neuraxial anaesthesia) by calculating adjusted incidence ratios for the following: differences in maternal age; geographical residence; deprivation; admission year; number of previous deliveries; and comorbidities. Women giving birth vaginally and by caesarean section were considered separately. For women undergoing elective caesarean births, after adjustment for available confounders, general anaesthesia was 58% more common in Caribbean (black or black British) women (adjusted incidence ratio [95%CI] 1.58 [1.26-1.97]) and 35% more common in African (black or black British) women (1.35 [1.19-1.52]). For women who had emergency caesarean births, general anaesthesia was 10% more common in Caribbean (black or black British) women (1.10 [1.00-1.21]) than British (white) women. For women giving birth vaginally (excluding assisted vaginal births), Bangladeshi (Asian or Asian British), Pakistani (Asian or Asian British) and Caribbean (black or black British) women were, respectively, 24% (0.76 [0.74-0.78]), 15% (0.85 [0.84-0.87]) and 8% (0.92 [0.89-0.94]) less likely than British (white) women to receive neuraxial anaesthesia. This observational study cannot determine the causes for these disparities, which may include unaccounted confounders. Our findings merit further research to investigate potentially remediable factors such as inequality of access to appropriate obstetric anaesthetic care.

The delivery of obstetric anaesthetic care in UK maternity units: a survey of practice in 2021.

BACKGROUND: Anaesthetists are crucial members of the maternity unit team, providing peri-operative analgesia and anaesthesia, and supporting the delivery of medical care to high-risk women. The effective contribution from obstetric anaesthetists to safety in maternity units depends on how anaesthesia services are organised and resourced. There is a lack of information on how obstetric anaesthetic care is resourced in the UK. METHODS: The Obstetric Anaesthetists' Association surveyed UK clinical leads for their hospital's obstetric anaesthetic service and examined compliance with national recommendations. RESULTS: There were 153 responses by lead obstetric anaesthetists from 184 maternity units in the UK (83%). The number of consultants per 1000 deliveries was 2.2 [1.6-2.7] (median [IQR]). In 20% of units, there was a dedicated on-call rota (on-call only for obstetric anaesthesia), whilst the remainder had a 'combined' on-call rota (on-call for other clinical areas in addition to obstetrics). Multidisciplinary ward rounds were held in 83% of units. Twenty-five (16%) units reported having no regular multidisciplinary ward rounds, of which nine (6%) did not have any multidisciplinary ward rounds. Planned operating lists for elective caesarean sections were provided in 77% of units. CONCLUSIONS: In the largest survey of obstetric anaesthesia workload to be reported for any health system, we found significant disparities between obstetric anaesthesia service provision and current national recommendations for areas including consultant staffing, support for elective caesarean section lists, antenatal anaesthetic clinics, and consultant support for service development. Wide national variation in service provision was identified.

High frequency ultrasound vibrational shear wave elastography for preclinical research.

Preclinical evaluation of novel therapies using models of cancer is an important tool in cancer research, where imaging can provide non-invasive tools to characterise the internal structure and function of tumours. The short propagation paths when imaging tumours and organs in small animals allow the use of high frequencies for both ultrasound and shear waves, providing the opportunity for high-resolution shear wave elastography and hence its use for studying the heterogeneity of tissue elasticity, where heterogeneity may be a predictor of tissue response. Here we demonstrate vibrational shear wave elastography (VSWE) using a mechanical actuator to produce high frequency (up to 1000 Hz) shear waves in preclinical tumours, an alternative to the majority of preclinical ultrasound SWE studies where an acoustic radiation force impulse is required to create a relatively low-frequency broad-band shear-wave pulse. We implement VSWE with a high frequency (17.8 MHz) probe running a focused line-by-line ultrasound imaging sequence which as expected was found to offer improved detection of 1000 Hz shear waves over an ultrafast planar wave imaging sequence in a homogenous tissue-mimicking phantom. We test the VSWE in anex vivotumour xenograft, demonstrating the ability to detect shear waves up to 10 mm from the contactor position at 1000 Hz. By reducing the kernel size used for shear wave speed estimation to 1 mm we are able to produce shear wave speed images with spatial resolution of this order. Finally, we present VSWE data from xenograft tumoursin vivo, demonstrating the feasibility of the technique in mice under isoflurane sedation. Mean shear wave speeds in the tumours are in good agreements with those reported by previous authors. Characterising the frequency dependence of shear wave speed demonstrates the potential to quantify the viscoelastic properties of tumoursin vivo.

Ice Sheet and Climate Processes Driving the Uncertainty in Projections of Future Sea Level Rise: Findings From a Structured Expert Judgement Approach.

The ice sheets covering Antarctica and Greenland present the greatest uncertainty in, and largest potential contribution to, future sea level rise. The uncertainty arises from a paucity of suitable observations covering the full range of ice sheet behaviors, incomplete understanding of the influences of diverse processes, and limitations in defining key boundary conditions for the numerical models. To investigate the impact of these uncertainties on ice sheet projections we undertook a structured expert judgement study. Here, we interrogate the findings of that study to identify the dominant drivers of uncertainty in projections and their relative importance as a function of ice sheet and time. We find that for the 21st century, Greenland surface melting, in particular the role of surface albedo effects, and West Antarctic ice dynamics, specifically the role of ice shelf buttressing, dominate the uncertainty. The importance of these effects holds under both a high-end 5°C global warming scenario and another that limits global warming to 2°C. During the 22nd century the dominant drivers of uncertainty shift. Under the 5°C scenario, East Antarctic ice dynamics dominate the uncertainty in projections, driven by the possible role of ice flow instabilities. These dynamic effects only become dominant, however, for a temperature scenario above the Paris Agreement 2°C target and beyond 2100. Our findings identify key processes and factors that need to be addressed in future modeling and observational studies in order to reduce uncertainties in ice sheet projections.

Pandemics and maternal health: the indirect effects of COVID-19.

Infectious diseases can directly affect women and men differently. During the COVID-19 pandemic, higher case fatality rates have been observed in men in most countries. There is growing evidence, however, that while organisational changes to healthcare delivery have occurred to protect those vulnerable to the virus (staff and patients), these may lead to indirect, potentially harmful consequences, particularly to vulnerable groups including pregnant women. These encompass reduced access to antenatal and postnatal care, with a lack of in-person clinics impacting the ability to screen for physical, psychological and social issues such as elevated blood pressure, mental health issues and sex-based violence. Indirect consequences also encompass a lack of equity when considering the inclusion of pregnant women in COVID-19 research and their absence from vaccine trials, leading to a lack of safety data for breastfeeding and pregnant women. The risk-benefit analysis of these changes to healthcare delivery remains to be fully evaluated, but the battle against COVID-19 cannot come at the expense of losing existing quality standards in other areas of healthcare, especially for maternal health.

Sea Level Budgets Should Account for Ocean Bottom Deformation.

The conventional sea level budget (SLB) equates changes in sea surface height with the sum of ocean mass and steric change, where solid-Earth movements are included as corrections but limited to the impact of glacial isostatic adjustment. However, changes in ocean mass load also deform the ocean bottom elastically. Until the early 2000s, ocean mass change was relatively small, translating into negligible elastic ocean bottom deformation (OBD), hence neglected in the SLB equation. However, recently ocean mass has increased rapidly; hence, OBD is no longer negligible and likely of similar magnitude to the deep steric sea level contribution. Here, we use a mass-volume framework, which allows the ocean bottom to respond to mass load, to derive a SLB equation that includes OBD. We discuss the theoretical appearance of OBD in the SLB equation and its implications for the global SLB.

The identification of key indicators to drive quality improvement in obstetric anaesthesia: results of the Obstetric Anaesthetists' Association/National Perinatal Epidemiology Unit collaborative Delphi project.

A three-stage Delphi survey process was undertaken to identify the quality indicators considered the most relevant to obstetric anaesthesia. The initial quality indicators assessed were derived from national peer-reviewed publications and were divided into service provision, service quality and clinical outcomes. A range of stakeholders were invited to participate and divided into three panels: obstetric anaesthetists; other maternity care health professionals; and women who had used maternity services. In total, 133 stakeholders registered to participate with 80% completing all three phases of the survey process. Participants ranked indicators for their relative importance using the grading of recommendations assessment, development and evaluation scale. From an initial list of 31 quality indicators, 11 indicators were rated as extremely important by > 90% of participants in at least two panels. These 11 indicators were presented to stakeholders; they were asked to vote for the five indicators they considered most relevant and useful for assessing and benchmarking the quality of obstetric anaesthesia provided. The indicators chosen were: the percentage of women who had an epidural/combined spinal-epidural for labour analgesia with accidental dural puncture; the presence of guidelines for the referral of patients to an anaesthetist for antenatal review; whether there are dedicated elective caesarean section lists; the availability of point-of-care testing for estimation of haemoglobin concentration; and the percentage of epidurals for labour analgesia that provided adequate pain relief within 45 min of the start of epidural insertion. These indicators may be used for quality improvement and national benchmarking to support the implementation of quality standards in obstetric anaesthesia.

Effectiveness of a quality improvement collaborative in reducing time to surgery for patients requiring emergency cholecystectomy.

Background: Acute gallstone disease is a high-volume emergency general surgery presentation with wide variations in the quality of care provided across the UK. This controlled cohort evaluation assessed whether participation in a quality improvement collaborative approach reduced time to surgery for patients with acute gallstone disease to fewer than 8 days from presentation, in line with national guidance. Methods: Patients admitted to hospital with acute biliary conditions in England and Wales between 1 April 2014 and 31 December 2017 were identified from Hospital Episode Statistics data. Time series of quarterly activity were produced for the Cholecystectomy Quality Improvement Collaborative (Chole-QuIC) and all other acute National Health Service hospitals (control group). A negative binomial regression model was used to compare the proportion of patients having surgery within 8 days in the baseline and intervention periods. Results: Of 13 sites invited to join Chole-QuIC, 12 participated throughout the collaborative, which ran from October 2016 to January 2018. Of 7944 admissions, 1160 patients had a cholecystectomy within 8 days of admission, a significant improvement (P < 0·050) from baseline performance. This represented a relative change of 1·56 (95 per cent c.i. 1·38 to 1·75), compared with 1·08 for the control group. At the individual site level, eight of the 12 Chole-QuIC sites showed a significant improvement (P < 0·050), with four sites increasing their 8-day surgery rate to over 20 per cent of all emergency admissions, well above the mean of 15·3 per cent for control hospitals. Conclusion: A surgeon-led quality improvement collaborative approach improved care for patients requiring emergency cholecystectomy.

Antecedentes: La patología biliar aguda litiásica es una de las urgencias con más volumen de casos en cirugía general, con amplias variaciones en la calidad de la atención prestada en todo el Reino Unido. En este estudio de cohortes controlado se valoró si la participación en un enfoque colaborativo de mejora de la calidad disminuía el tiempo hasta la cirugía en pacientes con patología biliar aguda litiásica a menos de 8 días desde la presentación, de acuerdo con la guía nacional. Métodos: Se identificó a los pacientes que precisaron un ingreso hospitalario por patología biliar aguda en Inglaterra y Gales, del 1 de abril de 2014 al 31 de diciembre de 2017, a partir de datos de las estadísticas de episodios hospitalarios. Se crearon series temporales de actividad trimestral para Chole­QuIC y para todos los demás hospitales de agudos del NHS (grupo control). Se utilizó un modelo de regresión binomial negativa para comparar la proporción de pacientes sometidos a cirugía dentro de los primeros 8 días en los periodos basal y de intervención. Resultados: De los 13 sitios invitados a unirse a Chole­QuIC, 12 participaron durante toda la colaboración, que se desarrolló entre octubre de 2016 y enero de 2018. De los 7.944 ingresos, en 1.160 pacientes se realizó la colecistectomía dentro de los 8 días posteriores a su ingreso, una mejora significativa (P < 0,05) en comparación con el periodo previo a la intervención. Esto representó un cambio relativo de 1,56 (i.c. del 95%: 1,38 a 1,75) en comparación con 1,08 para el grupo de control. A nivel de cada uno de los hospitales, ocho de los 12 centros Chole­QuIC presentaron una mejora significativa (P < 0,05), y en cuatro de ellos el porcentaje de cirugía en 8 días aumentó a más del 20% de todos los ingresos urgentes, muy por encima del promedio de 15,3% para hospitales de control. Conclusión: Un enfoque colaborativo de mejora de la calidad dirigido por el cirujano mejoró la atención a los pacientes que precisan una colecistectomía urgente.

Global ocean freshening, ocean mass increase and global mean sea level rise over 2005-2015.

Global mean sea level has experienced an unabated rise over the 20th century. This observed rise is due to both ocean warming and increasing continental freshwater discharge. We estimate the net ocean mass contribution to sea level by assessing the global ocean salt budget based on the unprecedented amount of in situ data over 2005-2015. We obtain the ocean mass trends of 1.30 ± 1.13 mm · yr-1 (0-2000 m) and 1.55 ± 1.20 mm · yr-1 (full depth). These new ocean mass trends are smaller by 0.63-0.88 mm · yr-1 compared to the ocean mass trend estimated through the sea level budget approach. Our result provides an independent validation of Gravity Recovery And Climate Experiment (GRACE)-based ocean mass trend and, in addition, places an independent constraint on the combined Glacial Isostatic Adjustment - the Earth's delayed viscoelastic response to the redistribution of mass that accompanied the last deglaciation- and geocenter variations needed to directly infer the ocean mass trend based on GRACE data.

Role of Greenland Freshwater Anomaly in the Recent Freshening of the Subpolar North Atlantic.

The cumulative Greenland freshwater flux anomaly has exceeded 5,000 km3 since the 1990s. The volume of this surplus freshwater is expected to cause substantial freshening in the North Atlantic. Analysis of hydrographic observations in the subpolar seas reveals freshening signals in the 2010s. The sources of this freshening are yet to be determined. In this study, the relationship between the surplus Greenland freshwater flux and this freshening is tested by analyzing the propagation of the Greenland freshwater anomaly and its impact on salinity in the subpolar North Atlantic based on observational data and numerical experiments with and without the Greenland runoff. A passive tracer is continuously released during the simulations at freshwater sources along the coast of Greenland to track the Greenland freshwater anomaly. Tracer budget analysis shows that 44% of the volume of the Greenland freshwater anomaly is retained in the subpolar North Atlantic by the end of the simulation. This volume is sufficient to cause strong freshening in the subpolar seas if it stays in the upper 50-100 m. However, in the model the anomaly is mixed down to several hundred meters of the water column resulting in smaller magnitudes of freshening compared to the observations. Therefore, the simulations suggest that the accelerated Greenland melting would not be sufficient to cause the observed freshening in the subpolar seas and other sources of freshwater have contributed to the freshening. Impacts on salinity in the subpolar seas of the freshwater transport through Fram Strait and precipitation are discussed.