Outcomes of heparinized adult veno-arterial extracorporeal membrane oxygenation patients managed with low and high activated partial thromboplastin time targets: A systematic review and meta-analysis

INTRODUCTION

There are no randomized controlled trials comparing low and high activated partial thromboplastin time (aPTT) targets in heparinized adult veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) patients. Our systematic review and meta-analysis summarized complication rates in adult VA ECMO patients treated with low and high aPTT targets.

METHODS

Studies published from January 2000 to May 2022 were identified using Pubmed, Embase, Cochrane Library, and LILACS (Latin American and Caribbean Health Sciences Literature). Studies were included if aPTT was primarily used to guide heparin anticoagulation. For the low aPTT group, we included studies where aPTT goal was ≤60 seconds and for the high aPTT group, we included studies where aPTT goal was ≥60 seconds. Proportional meta-analysis with a random effects model was used to calculate pooled complication rates for patients in the two aPTT groups.

RESULTS

Twelve studies met inclusion criteria (5 in the low aPTT group and 7 in the high aPTT group). The pooled bleeding complication incidence for low aPTT studies was 53.6% (95% CI = 37.4%-69.4%, I2 = 60.8%) and for high aPTT studies was 43.8% (95% CI = 21.7%-67.1%, I2 = 91.8%). No studies in the low aPTT group reported overall thrombosis incidence, while three studies in the high aPTT group reported overall thrombosis incidence. The pooled thrombosis incidence for high aPTT studies was 16.1% (95% CI = 9.0%-24.5%, I2 = 13.1%).

CONCLUSIONS

Adult ECMO patients managed with low and high aPTT goals appeared to have similar bleeding and other complication rates further highlighting the need for a randomized controlled trial.

Use of Simulation Resources for Underrepresented in Medicine Youth Engagement: A National Survey of Academic Anesthesiology Programs With Specified Diversity, Equity, and Inclusion Positions

Background The utilization of simulation resources can be an effective strategy to offer early medical exposure to underrepresented in medicine (URiM) youth populations, with the objective of promoting diversity in the field of medicine. Currently, it is unclear what proportion of academic anesthesiology programs with simulation centers utilize these resources for community engagement events. Methodology A survey was created using REDCap® and distributed via email to 38 anesthesiologists from 30 departments in the United States holding a leadership position dedicated to advancing diversity, equity, and inclusion. The survey assessed whether their programs had conducted community engagement events for URiM students, what simulation resources were available at their program, and which of these resources they had used at any community engagement events. Additionally, we assessed program characteristics such as region, academic versus community practice, and urban versus rural locations. Survey responses were collected between March and April 2023. Results We received responses from 15 of the 30 institutions sampled for an institutional response rate of 50%. The majority of respondents (86.7%) reported holding community engagement events. Most respondents reported a wide variety of simulation resources available, including 11 (73.3%) having access to full simulation centers. However, only three (27.3%) of the 11 with full simulation centers reported utilizing them for community events. Conclusions Despite the potential benefits of using simulation resources for community engagement events, our results suggest that academic anesthesiology departments may not commonly utilize simulation centers to provide URiM youth with exposure to the field of medicine. Anesthesiology departments with access to simulation resources are in a unique position to be leaders in advancing diversity in medicine by increasing URiM youth interest in medicine as a career through simulation-based exposure.

Optic Nerve Ultrasound for Monitoring Deteriorating Intracranial Hemorrhage in a Patient on Extracorporeal Membrane Oxygenation: A Case Report

We present a 52-year-old male patient with cardiogenic shock who was placed on veno-arterial extracorporeal membrane oxygenation (ECMO) as a bridge to an orthotopic heart transplant. While on ECMO, the patient developed an acute intracranial bleed confirmed on computerized tomography (CT). However, his clinical status deteriorated and he was unstable for transport to evaluate for worsening hemorrhage. Instead, optic nerve sheath (ONS) ultrasonography was utilized to confirm increased intracranial pressure, which guided the goals of care until he stabilized enough to transport for advanced imaging. Repeat CT confirmed the worsening of his cerebellar bleed with obstructing hydrocephalus and brainstem compression. This case demonstrates how ONS ultrasound can be utilized in a cardiothoracic intensive care unit to evaluate sedated patients for new or worsening intracranial hemorrhage. In ECMO patients, who are often unstable with the risks of transportation for CT outweighing potential benefits, ONS ultrasonography can provide the care team with meaningful data on a patient's neurologic status.

Variation in Hospitalization Costs, Charges, and Lengths of Hospital Stay for Coronavirus Disease 2019 Patients Treated With Venovenous Extracorporeal Membrane Oxygenation in the United States: A Cohort Study

OBJECTIVES

The aim was to characterize hospitalization costs, charges, and lengths of hospital stay for COVID-19 patients treated with venovenous (VV) extracorporeal membrane oxygenation (ECMO) in the United States during 2020. Secondarily, differences in hospitalization costs, charges, and lengths of hospital stay were explored based on hospital-level factors.

DESIGN

Retrospective cohort study.

SETTING

Multiple hospitals in the United States.

PARTICIPANTS

Adult patients with COVID-19 who were on VV ECMO in 2020 and had data in the national inpatient sample.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Demographics and baseline comorbidities were recorded for patients. Primary study outcomes were hospitalization costs, charges, and lengths of hospital stay. Study outcomes were compared after stratification by hospital region, bed size, and for-profit status. The median hospitalization cost for the 3,315-patient weighted cohort was $200,300 ($99,623, $338,062). Median hospitalization charges were $870,513 ($438,228, $1,553,157), and the median length of hospital stay was 30 days (17, 46). Survival to discharge was 54.4% for all patients in the cohort. Median hospitalization cost differed by region (p = 0.01), bed size (p < 0.001), and for-profit status (p = 0.02). Median hospitalization charges also differed by region (p = 0.04), bed size (p = 0.002), and for-profit status (p < 0.001). Length of hospital stay differed by region (p = 0.03) and bed size (p < 0.001), but not for-profit status (p = 0.40). Hospitalization costs were the lowest, and charges were highest in private-for-profit hospitals. Large hospitals also had higher costs, charges, and hospital stay lengths than small hospitals.

CONCLUSIONS

In this retrospective cohort study, hospitalization costs and charges for patients with COVID-19 on VV ECMO were found to be substantial but similar to what has been reported previously for patients without COVID-19 on VV ECMO. Significant variation was observed in costs, charges, and lengths of hospital stay based on hospital-level factors.

Utilization of Brain Tissue Oxygenation Monitoring and Association with Mortality Following Severe Traumatic Brain Injury

BACKGROUND

The aim of this study was to describe the utilization patterns of brain tissue oxygen (PbtO₂) monitoring following severe traumatic brain injury (TBI) and determine associations with mortality, health care use, and pulmonary toxicity.

METHODS

We conducted a retrospective cohort study of patients from United States trauma centers participating in the American College of Surgeons National Trauma Databank between 2008 and 2016. We examined patients with severe TBI (defined by admission Glasgow Coma Scale score ≤ 8) over the age of 18 years who survived more than 24 h from admission and required intracranial pressure (ICP) monitoring. The primary exposure was PbtO₂ monitor placement. The primary outcome was hospital mortality, defined as death during the hospitalization or discharge to hospice. Secondary outcomes were examined to determine the association of PbtO₂ monitoring with health care use and pulmonary toxicity and included the following: (1) intensive care unit length of stay, (2) hospital length of stay, and (3) development of acute respiratory distress syndrome (ARDS). Regression analysis was used to assess differences in outcomes between patients exposed to PbtO₂ monitor placement and those without exposure by using propensity weighting to address selection bias due to the nonrandom allocation of treatment groups and patient dropout.

RESULTS

A total of 35,501 patients underwent placement of an ICP monitor. There were 1,346 (3.8%) patients who also underwent PbtO₂ monitor placement, with significant variation regarding calendar year and hospital. Patients who underwent placement of a PbtO₂ monitor had a crude in-hospital mortality of 31.1%, compared with 33.5% in patients who only underwent placement of an ICP monitor (adjusted risk ratio 0.84, 95% confidence interval 0.76-0.93). The development of the ARDS was comparable between patients who underwent placement of a PbtO₂ monitor and patients who only underwent placement of an ICP monitor (9.2% vs. 9.8%, adjusted risk ratio 0.89, 95% confidence interval 0.73-1.09).

CONCLUSIONS

PbtO₂ monitor utilization varied widely throughout the study period by calendar year and hospital. PbtO₂ monitoring in addition to ICP monitoring, compared with ICP monitoring alone, was associated with a decreased in-hospital mortality, a longer length of stay, and a similar risk of ARDS. These findings provide further guidance for clinicians caring for patients with severe TBI while awaiting completion of further randomized controlled trials.

Should cardiac rehabilitation programmes be specifically targeting sedentary time?

Funding Acknowledgements

Type of funding sources: None.

Background / Introduction

Structured exercise classes and advice regarding regular moderate intensity physical activity are well-established components of cardiac rehabilitation (CR). Sedentary behaviour, refers to activities typically sitting or lying that do not substantially increase energy expenditure above resting, and increasing evidence suggests adults should limit their sedentary time to less than 9 hours/day as such behaviour with increased cardiovascular and all-cause mortality with additional benefits likely gained sitting less than 6-8 hours/day. Nonetheless sedentary behaviours are often overlooked or are only partially assessed via self-report in CR programmes. Due to covid restrictions (lockdown, social distancing, suspension of face-to-face CR programmes) there is concern that sedentary time may further increase in this population. Thus, it may be important to effectively monitor and target sedentary time, alongside traditional advice, to minimise its negative health impacts.

Purpose

Can a CR programme, adapted to remote delivery due to covid, objectively measure sedentary behaviour in a way that is feasible in every day practice and acceptable to patients?

Methods

Consecutive cardiovascular patients attending an initial assessment (via telephone or video) on the Our Hearts Our Minds Programme for Cardiovascular Health between December 2020 and February 2021 were asked to wear activPAL (PAL technologies Ltd., Glasgow, UK), a triaxial accelerometer, on their thigh for 7 days to measure the postural aspect of sedentary behaviour. On return of the monitor, the data was analysed using proprietary algorithms (intelligent activity classification) generating a report summarising time spent sitting, prolonged sitting, step count average, number of sit to stand transitions, moderate intensity activity minutes, most sedentary time(s) of the day and percentages spent in these activities. This personalised report was shared with the patient and their goals in terms of sedentary behaviour and physical activity were discussed and agreed.

Results

59 referrals were received between mid December 2020 and February 2021, of which 52 had an initial virtual assessment. Of these, 50 patients accepted an activPAL (96% response rate). Mean age 62.6 years. The output from the activPal is shown in table 1. The average sitting time overall was 9 hours 36 minutes. The breakdown in proportions sitting for extended periods of time are detailed in table below

Conclusion

2/3 of cardiovascular patients attending CR had levels of sitting time greater than what is recommended following their IA. Measuring sedentary time beyond self-report in CR programmes using activPal was feasible in a CR programme with 96% of consecutive patients wearing and returning activPAL.  Repeat analysis at end of programme will show if use of this data results in reduction of same .

Mapping QTL for dollar spot resistance in creeping bentgrass (Agrostis stolonifera L.)

Dollar spot caused by Sclerotinia homoeocarpa F. T. Bennett is the most economically important turf disease on golf courses in North America. Dollar spot resistance in a creeping bentgrass cultivar would greatly reduce the frequency, costs, and environmental impacts of fungicide application. Little work has been done to understand the genetics of resistance to dollar spot in creeping bentgrass. Therefore, QTL analysis was used to determine the location, number and effects of genomic regions associated with dollar spot resistance in the field. To meet this objective, field inoculations using a single isolate were performed over 2 years and multiple locations using progeny of a full sib mapping population '549 x 372'. Dollar spot resistance seems to be inherited quantitatively and broad sense heritability for resistance was estimated to be 0.88. We have detected one QTL with large effect on linkage group 7.1 with LOD values ranging from 3.4 to 8.6 and explaining 14-36% of the phenotypic variance. Several smaller effect QTL specific to rating dates, locations and years were also detected. The association of the tightly linked markers with the LG 7.1 QTL based on 106 progeny was further examined by single marker analysis on all 697 progeny. The high significance of the QTL on LG 7.1 at a sample size of 697 (P < 0.0001), along with its consistency across locations, years and ratings dates, indicated that it was stable over environments. Markers tightly linked to the QTL can be utilized for marker-assisted selection in future bentgrass breeding programs.

QTL mapping of resistance to gray leaf spot in ryegrass

Gray leaf spot (GLS) is a serious fungal disease caused by Magnaporthe grisea, recently reported on perennial ryegrass (Lolium perenne L.), an important turf grass and forage species. This fungus also causes rice blast and many other grass diseases. Rice blast is usually controlled by host resistance, but durability of resistance is a problem. Little GLS resistance has been reported in perennial ryegrass. However, greenhouse inoculations in our lab using one ryegrass isolate and one rice-infecting lab strain suggest presence of partial resistance. A high density linkage map of a three generation Italian x perennial ryegrass mapping population was used to identify quantitative trait loci (QTL) for GLS resistance. Potential QTL of varying effect were detected on four linkage groups, and resistance to the ryegrass isolate and the lab strain appeared to be controlled by different QTL. Of three potential QTL detected using the ryegrass isolate, the one with strongest effect for resistance was located on linkage group 3 of the MFB parent, explaining between 20% and 37% of the phenotypic variance depending on experiment. Another QTL was detected on linkage group 6 of the MFA parent, explaining between 5% and 10% of the phenotypic variance. The two QTL with strongest effect for resistance to the lab strain were located on linkage groups MFA 2 and MFB 4, each explaining about 10% of the phenotypic variance. Further, the QTL on linkage groups 3 and 4 appear syntenic to blast resistance loci in rice. This work will likely benefit users and growers of perennial ryegrass, by setting the stage for improvement of GLS resistance in perennial ryegrass through marker-assisted selection.

QTL mapping of resistance to gray leaf spot in ryegrass

Gray leaf spot (GLS) is a serious fungal disease caused by Magnaporthe grisea, recently reported on perennial ryegrass (Lolium perenne L.), an important turf grass and forage species. This fungus also causes rice blast and many other grass diseases. Rice blast is usually controlled by host resistance, but durability of resistance is a problem. Little GLS resistance has been reported in perennial ryegrass. However, greenhouse inoculations in our lab using one ryegrass isolate and one rice-infecting lab strain suggest presence of partial resistance. A high density linkage map of a three generation Italian x perennial ryegrass mapping population was used to identify quantitative trait loci (QTL) for GLS resistance. Potential QTL of varying effect were detected on four linkage groups, and resistance to the ryegrass isolate and the lab strain appeared to be controlled by different QTL. Of three potential QTL detected using the ryegrass isolate, the one with strongest effect for resistance was located on linkage group 3 of the MFB parent, explaining between 20% and 37% of the phenotypic variance depending on experiment. Another QTL was detected on linkage group 6 of the MFA parent, explaining between 5% and 10% of the phenotypic variance. The two QTL with strongest effect for resistance to the lab strain were located on linkage groups MFA 2 and MFB 4, each explaining about 10% of the phenotypic variance. Further, the QTL on linkage groups 3 and 4 appear syntenic to blast resistance loci in rice. This work will likely benefit users and growers of perennial ryegrass, by setting the stage for improvement of GLS resistance in perennial ryegrass through marker-assisted selection.

Chromosomal rearrangements differentiating the ryegrass genome from the Triticeae, oat, and rice genomes using common heterologous RFLP probes

An restriction fragment length polymorphism (RFLP)-based genetic map of ryegrass (Lolium) was constructed for comparative mapping with other Poaceae species using heterologous anchor probes. The genetic map contained 120 RFLP markers from cDNA clones of barley (Hordeum vulgare L.), oat (Avena sativa L.), and rice (Oryza sativa L.), covering 664 cM on seven linkage groups (LGs). The genome comparisons of ryegrass relative to the Triticeae, oat, and rice extended the syntenic relationships among the species. Seven ryegrass linkage groups were represented by 10 syntenic segments of Triticeae chromosomes, 12 syntenic segments of oat chromosomes, or 16 syntenic segments of rice chromosomes, suggesting that the ryegrass genome has a high degree of genome conservation relative to the Triticeae, oat, and rice. Furthermore, we found ten large-scale chromosomal rearrangements that characterize the ryegrass genome. In detail, a chromosomal rearrangement was observed on ryegrass LG4 relative to the Triticeae, four rearrangements on ryegrass LGs2, 4, 5, and 6 relative to oat, and five rearrangements on ryegrass LGs1, 2, 4, 5, and 7 relative to rice. Of these, seven chromosomal rearrangements are reported for the first time in this study. The extended comparative relationships reported in this study facilitate the transfer of genetic knowledge from well-studied major cereal crops to ryegrass.

Policy lessons from children's allowances for children's savings accounts

This article examines the history and current structure of children's allowances around the world as well as the history of such allowances in the United States in an effort to provide the United States with a policy framework for children's savings accounts. The authors also provide policy direction for children's savings accounts.

Grazing incidence synchrotron X-ray topography as a tool for denuded zone studies of silicon wafers

Reflection topographs of annealed Czochralski-grown silicon wafers are made with synchrotron white beam radiation at grazing angles of 0.2 degree to 3 degree. Information on the uniformity of the denuded zone is obtained from a number of grazing incidence topographs, which according to calculations turn out to be almost completely monochromatic having a negligible harmonic content. The calculated penetration depth ranges from 1 to 100 µm depending on the grazing angle and reflection used. The grazing incidence topographs are compared with section topographs of the same samples.

Glucocorticoids prolong rat sciatic nerve blockade in vivo from bupivacaine microspheres

BACKGROUND

Previous work showed that incorporation of dexamethasone (0.05 weight/weight percentage) into bupivacaine microspheres prolonged blockade by eight to 13 times compared with that produced by bupivacaine microspheres alone. The determinants of dexamethasone's block-prolonging effect were examined and reported here.

METHODS

Polylactic-co-glycolic acid polymer microspheres (65/35) with 75 weight/weight percentage bupivacaine were prepared. Microspheres were injected adjacent to the rat sciatic nerve, and sensory and motor blockade were assessed. A procedure was developed to test drugs for block-prolonging ability in vivo by placing test drugs in the injection fluid along with a suspension of bupivacaine microspheres.

RESULTS

Dexamethasone alone in suspension did not produce blockade, nor did it prolong blockade induced by aqueous bupivacaine. Bupivacaine microspheres (150 mg drug/kg rat weight) produced blockade for 6 to 10 h. Dexamethasone in the suspending solution of microspheres prolonged block by up to five times. Glucocorticoids prolonged block in proportion to glucocorticoid/antiinflammatory potency. The corticosteroid antagonist cortexolone inhibited dexamethasone's blockade-prolonging action. Durations of blockade with or without dexamethasone were unaltered by hydroxyurea-induced neutrophil depletion. Microspheres were extracted from rats at time points ranging from 7 h to 7 days, and residual microsphere dry weight and bupivacaine content were similar in groups of rats injected with either bupivacaine microspheres or bupivacaine microspheres containing dexamethasone, respectively.

CONCLUSIONS

Glucocorticoids prolong blockade from bupivacaine microspheres. The mechanism appears unrelated to the kinetics of bupivacaine release in vivo.

Prolonged regional nerve blockade. Injectable biodegradable bupivacaine/polyester microspheres

BACKGROUND

Biodegradable microspheres are a useful method of drug delivery because they are both injectable and biodegradable, eliminating the need for surgical implantation or removal. Previous work has characterized implantable preparations of local anesthetics in polymer pellets for prolonged regional anesthesia. In this article, the authors characterize injectable suspensions of bupivacaine-polymer microspheres and examine whether they can produce prolonged blockade of the sciatic nerve in rats.

METHODS

Microspheres were prepared using polylactic-co-glycolic acid polymers loaded with 75% w/w bupivacaine by a solvent evaporation method. Bupivacaine release from microspheres was determined in vitro by ultraviolet spectroscopy and scintillation counting. Sensory and motor blockade of the rat sciatic nerve were assessed in vivo after injection of microsphere suspensions.

RESULTS

Depending on the type of microspheres, the dose, and the additive used, mean duration of sciatic nerve block ranged from 10 h to 5.5 days. Incorporation of 0.05% w/w dexamethasone into the microspheres resulted in significant prolongation of block (up to 13-fold), and only preparations that contained dexamethasone produced blocks lasting beyond 1 day. Bupivacaine was released in a controlled manner in vitro. Dexamethasone does not substantially slow bupivacaine release from microspheres in vitro.

CONCLUSIONS

Prolonged percutaneous blockade of peripheral nerves is feasible. The recovery from blockade is complete, and plasma bupivacaine levels are far below the range associated with systemic toxicity. The mechanisms underlying the dexamethasone block-prolonging effect are under investigation.

Tissue localization of methotrexate-monoclonal-IgM immunoconjugates: anti-SSEA-1 and MOPC 104E in mouse teratocarcinomas and normal tissues

Methotrexate (MTX) was coupled to the tumor-targeting monoclonal IgM, anti-SSEA-1 and the non-targeting myeloma IgM, MOPC 104E. At 24-h intervals following injection, drug deposition in MH-15 teratocarcinomas and in several normal tissues was followed by immunoperoxidase microscopy using the M16 monoclonal antibody to MTX. MTX-anti-SSEA-1 was deposited on the surface and in the interior of living tumor cells 24 h after injection; at 48 h and after, only low-level binding to necrotic tissue was found. There was no significant gradation in staining from the outside to the interior of the tumors. In tumors, the control MOPC 104E immunoconjugate was detectable only in necrotic tissue. Binding to SSEA-1-expressing normal tissues was undetectable, except for pericryptal fibroblasts in the small intestine. No significant pathology was found in normal tissues that are SSEA-1 positive. High levels of the immunoconjugate were detected in the liver, where MTX was found predominantly in Kupffer cells and possibly in hepatocytes; again, no significant morphological changes were associated with this retention. Thus tumor-associated antigens can be suitable targets for antibody-drug conjugates even when present in normal tissues and in large quantities, provided that the antigens in normal tissues are inaccessible. Moreover, deposition in viable tumor tissue can be assessed using monoclonal antibodies to methotrexate.

A retrospective review of undifferentiated malignancy in childhood

We reviewed the experience of children with "undifferentiated" cancer at The Children's Hospital of Pittsburgh (CHP) from 1971 through 1987. Of 2,095 patients 0-18 years old with diagnoses during that time of any cancer, the initial CHP pathology report rendered a diagnosis in 22 children (1.1%) of "undifferentiated malignancy" or "malignant tumor" (15 cases), "undifferentiated carcinoma" (two cases) or "anaplastic tumor or carcinoma" not otherwise specified (five cases). A review of pathologic findings using current methods and immunostaining led to the assignment of a specific diagnosis in 15 of the 20 cases so studied. Thus, the incidence of undifferentiated cancer by current criteria was reduced to no more than 0.23%. Two of the five tumors for which an alternative diagnosis could not be established were described as "rhabdoid," but because it is not clear that these tumors fit into a single category they were still considered to be undifferentiated. Clinical features and management of the 22 cases including the five persistently diagnosed as undifferentiated malignancy were heterogeneous. In the face of reassigned diagnoses, a number of patients would likely have received different chemotherapy as well as radiation. Nonetheless, seven patients with malignancy show no evidence of disease (NED), including several whose therapy, given the current best diagnosis, would not be considered to have been optimal. We recommend that for patients undergoing biopsy of a tumor, sufficient material be obtained for extensive pathologic evaluation. In this way, the diagnosis of undifferentiated malignancy in children can be almost eliminated.(ABSTRACT TRUNCATED AT 250 WORDS)

Vancomycin and tobramycin in the treatment of CAPD peritonitis

Seventy-five episodes of continuous ambulatory peritoneal dialysis (CAPD) peritonitis were studied during a 1 year period at the Queen Elizabeth Hospital, Birmingham. When two simple culture methods were used in parallel, the causative organisms were identified in 97% of cases. Nearly two thirds of episodes of peritonitis were caused by coagulase-negative staphylococci (C-NS), many of which were multiply antibiotic-resistant. On the basis of detailed antibiotic sensitivities, intraperitoneal vancomycin and tobramycin were chosen for the initial treatment of CAPD peritonitis. With this regime, a cure was achieved in 32 of 38 episodes, compared with 15 of 27 episodes when cefuroxime was used. All but 1 of 24 episodes caused by C-NS were cured by vancomycin.