Physiological Adverse Events Research Articles

Early adverse physiological event detection using commercial wearables: challenges and opportunities

Data from commercial off-the-shelf (COTS) wearables leveraged with machine learning algorithms provide an unprecedented potential for the early detection of adverse physiological events. However, several challenges inhibit this potential, including (1) heterogeneity among and within participants that make scaling detection algorithms to a general population less precise, (2) confounders that lead to incorrect assumptions regarding a participant’s healthy state, (3) noise in the data at the sensor level that limits the sensitivity of detection algorithms, and (4) imprecision in self-reported labels that misrepresent the true data values associated with a given physiological event. The goal of this study was two-fold: (1) to characterize the performance of such algorithms in the presence of these challenges and provide insights to researchers on limitations and opportunities, and (2) to subsequently devise algorithms to address each challenge and offer insights on future opportunities for advancement. Our proposed algorithms include techniques that build on determining suitable baselines for each participant to capture important physiological changes and label correction techniques as it pertains to participant-reported identifiers. Our work is validated on potentially one of the largest datasets available, obtained with 8000+ participants and 1.3+ million hours of wearable data captured from Oura smart rings. Leveraging this extensive dataset, we achieve pre-symptomatic detection of COVID-19 with a performance receiver operator characteristic (ROC) area under the curve (AUC) of 0.725 without correction techniques, 0.739 with baseline correction, 0.740 with baseline correction and label correction on the training set, and 0.777 with baseline correction and label correction on both the training and the test set. Using the same respective paradigms, we achieve ROC AUCs of 0.919, 0.938, 0.943 and 0.994 for the detection of self-reported fever, and 0.574, 0.611, 0.601, and 0.635 for detection of self-reported shortness of breath. These techniques offer improvements across almost all metrics and events, including PR AUC, sensitivity at 75% specificity, and precision at 75% recall. The ring allows continuous monitoring for detection of event onset, and we further demonstrate an improvement in the early detection of COVID-19 from an average of 3.5 days to an average of 4.1 days before a reported positive test result.

Pole balancing on the fingertip: model-motivated machine learning forecasting of falls.

Introduction: There is increasing interest in developing mathematical and computational models to forecast adverse events in physiological systems. Examples include falls, the onset of fatal cardiac arrhythmias, and adverse surgical outcomes. However, the dynamics of physiological systems are known to be exceedingly complex and perhaps even chaotic. Since no model can be perfect, it becomes important to understand how forecasting can be improved, especially when training data is limited. An adverse event that can be readily studied in the laboratory is the occurrence of stick falls when humans attempt to balance a stick on their fingertips. Over the last 20 years, this task has been extensively investigated experimentally, and presently detailed mathematical models are available. Methods: Here we use a long short-term memory (LTSM) deep learning network to forecast stick falls. We train this model to forecast stick falls in three ways: 1) using only data generated by the mathematical model (synthetic data), 2) using only stick balancing recordings of stick falls measured using high-speed motion capture measurements (human data), and 3) using transfer learning which combines a model trained using synthetic data plus a small amount of human balancing data. Results: We observe that the LTSM model is much more successful in forecasting a fall using synthetic data than it is in forecasting falls for models trained with limited available human data. However, with transfer learning, i.e., the LTSM model pre-trained with synthetic data and re-trained with a small amount of real human balancing data, the ability to forecast impending falls in human data is vastly improved. Indeed, it becomes possible to correctly forecast 60%-70% of real human stick falls up to 2.35 s in advance. Conclusion: These observations support the use of model-generated data and transfer learning techniques to improve the ability of computational models to forecast adverse physiological events.

Get on the Round Dial: Fighter Pilot Strategies for Recovering Situation Awareness After Disorienting Physiological Events

Despite decades of research and training, adverse physiological events continue to present a significant risk to pilots. This paper describes a naturalistic study of fighter pilot experiences with disorienting physiological events such as gravity-induced loss of consciousness (G-LOC), hypoxia, and spatial disorientation. We conducted a cognitive task analysis with 10 experienced fighter pilots to elicit incidents in which the pilot or another pilot in the flight experienced a physiological event, exploring how they recognized something was wrong, assessed the level of impairment, and regained situation awareness. We describe cognitive requirements, specific cues and strategies, as well as complexities associated with managing these disorienting physiological events. Implications for decision support design and training are discussed.

Inspiratory threshold loading negatively impacts attentional performance.

RationaleThere are growing concerns over the occurrence of adverse physiologic events (PEs) occurring in pilots during operation of United States Air Force and Navy high-performance aircraft. We hypothesize that a heightened inspiratory work of breathing experienced by jet pilots by virtue of the on-board life support system may constitute a “distraction stimulus” consequent to an increased sensation of respiratory muscle effort. As such, the purpose of this study was to determine whether increasing inspiratory muscle effort adversely impacts on attentional performance.MethodsTwelve, healthy participants (age: 29 ± 6 years) were recruited for this study. Participants completed six repetitions of a modified Masked Conjunctive Continuous Performance Task (MCCPT) protocol while breathing against four different inspiratory threshold loads to assess median reaction times (RTs). A computer-controlled threshold loading device was used to set the inspiratory threshold loads. Repeated measures analysis of variances (ANOVAs) were performed to examine: (i) the efficacy of the threshold loading device to impose significantly higher loading at each loading condition; (ii) the effects of loading condition on respiratory muscle effort sensation; and (iii) the influence of hypercapnia on MCCPT scores during inspiratory threshold loading. Generalized additive mixed effects models (GAMMs) were used to examine the potential non-linear effects of respiratory muscular effort sensation, device loading, and hypercapnia, on MCCPT scores during inspiratory threshold loading.ResultsInspiratory threshold loading significantly augmented (P < 0.05) inspiratory effort sensation and the inspiratory pressure-time product (PTP). Our analyses also revealed that median hit RT was positively associated with inspiratory effort sensation during inspiratory loading trials.ConclusionThe findings of this work suggest that it was not increasing inspiratory muscle effort (i.e., PTP) per se, but rather participant’s subjective perception of inspiratory “load” that impacts negatively on attentional performance; i.e., as the degree of inspiratory effort sensation increased, sotoo did median hit RT. As such, it is reasonable to suggest that minimizing inspiratory effort sensation (independent of the mechanical output of the inspiratory muscles) during high-performance flight operations may prove useful in reducing pilot RTs during complex behavioral tasks.

Physiological Effects of Binary Mixtures of Common Bath Salt Constituents: Studies with MDPV, Methylone, and Caffeine in Rats

It is becoming increasingly clear among treatment providers, policy makers, and basic scientists alike, that polysubstance abuse is the norm rather than the exception. This is supported by the increased incidence of drug mixtures in drug overdoses, both fatal and nonfatal. In particular, toxicity produced via use of multiple substances has been highlighted by “bath salts” mixtures, often comprising at least one synthetic cathinone (e.g. 3,4‐methylenedioxypyrovalerone [MDPV] or 3,4‐methylenedioxy‐N‐methylcathinone [methylone]), in addition to other stimulants such as caffeine. Use of these drug mixtures has garnered much attention in the popular press due to frequent reports of bizarre behaviors, and adverse psychiatric (paranoia, hallucinations, aggression) and physiological (tachycardia, hypertension, hyperthermia) events leading to large numbers of emergency room visits and/or death. Although synergistic interactions between the reinforcing effects of common “bath salts” constituents have been observed (e.g., greater than predicted breakpoints under a progressive ratio schedule of reinforcement and greater economic demand), much less is known regarding interactions between the physiological effects of these drugs. The goal of the current study was to characterize the behavioral, cardiovascular, and thermoregulatory effects of MDPV, methylone, and caffeine, and subsequently, to determine the nature of the interactions between binary mixtures of these drugs. Male Sprague Dawley rats were implanted with an intravenous catheter and a radio‐telemetric probe capable of recording core body temperature, heart rate, blood pressure, and locomotor activity. Rats were habituated to the test chamber for one hour before receiving an intravenous infusion of either MDPV (0.032‐3.2 mg/kg), methylone (0.1‐10 mg/kg), caffeine (0.32‐32 mg/kg), or a binary mixture (3:1, 1:1, or 1:3) of methylone+MDPV, methylone+caffeine, or MDPV+caffeine. Recordings continued for six hours following drug administration. MDPV, methylone, and caffeine produced dose‐dependent increases in core body temperature (caffeine &gt; MDPV &gt; methylone), blood pressure (MDPV &gt; caffeine &gt; methylone), heart rate (methylone &gt; MDPV &gt; caffeine), and locomotor activity (MDPV &gt; caffeine = methylone) relative to baseline measurements. MDPV was more potent than methylone, which was more potent than caffeine. Binary mixtures of methylone+MDPV, methylone+caffeine, and MDPV+caffeine resulted in largely additive interactions across all endpoints, with possible departures from additivity observed at the largest dose‐pairs evaluated. These data demonstrate that intravenous administration of either MDPV, methylone, or caffeine alters temperature, heart rate, blood pressure, and locomotor activity in a dose‐dependent manner, consistent with what has been reported in “bath salts” users in emergency room settings. To more deeply characterize the interactions between these constituents, future studies will determine the degree to which the reinforcing and physiological effects of these drug mixtures could be mediated by pharmacokinetic interactions between individual constituents.

Effectiveness of Reverse Kangaroo Mother Care Position in Decreasing Adverse Physiological Events and Pain during Screening of Premature Infants for Retinopathy of Prematurity

Background. Retinopathy of prematurity (ROP) screening is uncomfortable and even painful in preterm infants.&#x0D; Objective. To determine the effectiveness of the Reverse-Kangaroo Mother Care (R-KMC) position compared with the conventional position in decreasing adverse physiological events and pain during ROP screening.&#x0D; Methods. This was a parallel randomized controlled trial with two arms- R-KMC position and conventional position (control). The primary outcomes included increased oxygen saturation, decreased heart and respiratory rates, and decreased pain intensity measured by Prematurity Infant Pain Profile (PIPP).&#x0D; Results. There were 100 preterm infants recruited. There were no differences in baseline characteristics, mean ROP screening duration, mean physiological parameters after the mydriatic application and during ROP screening between the two. Only the mean respiratory rates were significantly lower among the R-KMC group during the application of mydriatric agent. (50.26 ± 6.18 vs. 51.6 ± 8.35; p=0.0191). Relative risk (RR) in the control group is 37 to 84 versus 40 to 68 in the R-KMC group. The R-KMC group had a significantly lower mean PIPP score (6.5±2.06 vs. 8.8±2.80; p&lt;0.0001) after mydriatic application and during ROP screening (7.6±2.05 vs. 9.8±2.90; p&lt;0.0001) compared with control. No apnea was observed after mydriatic application, but one apneic episode was in control during ROP screening. 26% of the ROP screeners recommended the R-KMC position during ROP screening, while a majority (70%) was neutral.&#x0D; Conclusion. R-KMC position, a low-cost intervention, significantly reduces pain during ROP screening. It is recommended as a position of choice during ROP screening.

Abstract NS6: Early Mobility Initiated at 12 Hours Post Thrombolytic Therapy for Stroke Increases Likelihood for Discharge to Home

Purpose: To assess patient safety and discharge outcomes of initiating early mobility after 12 hours of receiving thrombolytic therapy (tPA) for stroke at a Primary Stroke Center. Background: Patients receiving tPA are traditionally maintained on bedrest for 24 hours due to an alleged risk of increased complications or falls, however this standard is not supported by data. Prior data among patients receiving tPA supports the concept of providing early mobility before 24 hours without an increased risk of falls or other adverse response. There is also evidence that early mobility in other critical care populations has positive impact on discharge disposition and decreasing the length of stay (LOS). Methods: A validated Early Mobility Protocol was implemented within 24 hours for all patients receiving tPA for stroke with a focus to progress each patient through the stages of the mobility protocol based on clinical presentation. Data from pre-implementation (January – May 2018) and post implementation (June 2018-December 2018) were compared for outcomes, including discharge disposition, adverse responses and LOS. T-test and Chi-square were used to determine significant difference in outcomes between groups. Results: Between January to December 2018 44 patients received tPA (18 pre-implementation and 26 post implementation). For the post implementation group 18/26 early mobility was initiated with 24 hours, 4/26 were placed on comfort care and 4/26 were transferred to a comprehensive stroke center. Among the early mobility group, there were no falls or adverse physiological events. Patients that participated with early mobility were more likely to discharge home, 46.15% vs 33.33%, less likely to require post-acute services, 15.38% vs 27.78%, and less likely to require transfer to a higher level of care, 15.38% vs 33.78%. There was not a significant difference in LOS. Conclusion: Providing early mobility to patients post thrombolytic therapy between 12-24 hours does not cause an increase in adverse physiological events. Additionally, providing early mobility has a positive impact on patient discharges to home. Further study may include initiating mobility at an early timeframe to examine the correlation to LOS and discharge outcomes.

Abstract TMP41: Early Mobility Initiated at 12 Hours Post Thrombolytic Therapy for Stroke Increases Likelihood for Discharge to Home

Purpose: To assess patient safety and discharge outcomes of initiating early mobility after 12 hours of receiving thrombolytic therapy (tPA) for stroke at a Primary Stroke Center. Background: Patients receiving tPA are traditionally maintained on bedrest for 24 hours due to an alleged risk of increased complications or falls, however this standard is not supported by data. Prior data among patients receiving tPA supports the concept of providing early mobility before 24 hours without an increased risk of falls or other adverse response. There is also evidence that early mobility in other critical care populations has positive impact on discharge disposition and decreasing the length of stay (LOS). Methods: A validated Early Mobility Protocol was implemented within 24 hours for all patients receiving tPA for stroke with a focus to progress each patient through the stages of the mobility protocol based on clinical presentation. Data from pre-implementation (January – May 2018) and post implementation (June 2018-December 2018) were compared for outcomes, including discharge disposition, adverse responses and LOS. T-test and Chi-square were used to determine significant difference in outcomes between groups. Results: Between January to December 2018 44 patients received tPA (18 pre-implementation and 26 post implementation). For the post implementation group 18/26 early mobility was initiated with 24 hours, 4/26 were placed on comfort care and 4/26 were transferred to a comprehensive stroke center. Among the early mobility group, there were no falls or adverse physiological events. Patients that participated with early mobility were more likely to discharge home, 46.15% vs 33.33%, less likely to require post-acute services, 15.38% vs 27.78%, and less likely to require transfer to a higher level of care, 15.38% vs 33.78%. There was not a significant difference in LOS. Conclusion: Providing early mobility to patients post thrombolytic therapy between 12-24 hours does not cause an increase in adverse physiological events. Additionally, providing early mobility has a positive impact on patient discharges to home. Further study may include initiating mobility at an early timeframe to examine the correlation to LOS and discharge outcomes.

Reducing Anesthesia Use for Pediatric Magnetic Resonance Imaging: The Effects of a Patient- and Family-Centered Intervention on Image Quality, Health-care Costs, and Operational Efficiency

Children with complex medical problems who require anesthesia are known to be at risk for acute adverse physiologic events related to anesthesia. The risks of anesthesia include short- and long-term psychological and neurobehavioral issues. Magnetic resonance imaging (MRI) has emerged as the standard of care for diagnosis and follow-up of many conditions, and more children are being subjected to anesthesia to ensure acceptable motion-free image quality of the MRI scans. The aim of this study was to evaluate the effectiveness of an anesthesia-free patient- and family-centered intervention through an analysis of MRI quality, health-care costs, and operational efficiency as compared with other approaches. This study retrospectively reviewed patient data extracted from electronic medical records of children aged 3-17 years, who underwent outpatient MRI at an urban academic medical center from 2015 to 2016. A total matched sample size of 500 children, 125 per group, was used to investigate the outcome variables including the quality of magnetic resonance image, health-care cost, and procedural time. The groups included are as follows: (1) intervention group, patient- and family-centered preparation of the child, and no anesthesia given (PFC/NA); (2) comparison group, no structured preparation, and no anesthesia given (SC/NA); (3) comparison group, certified child life specialist preparation, and anesthesia given (CCLS/A); (4) comparison group, no structured preparation, anesthesia given (SC/A). The PFC/NA intervention group was found to have significantly lower costs (p < .0001) and shorter procedure times (p < .0001), and 96.8% of the MRI images were of acceptable or better quality than those of the SC/A and CCLS/A groups. The PFC approach provides a way for children to undergo outpatient diagnostic MRI without the need for anesthesia, thus reducing risk, costs, and procedure time.

144: THE PHYSIOLOGICAL INFORMATION ROLE FOR STROKE PATIENTS

Background and aims:Stroke is the third biggest cause of mortality and the main cause of disability in world. The world health organization (WHO) definition of stroke is a focal neurological...

Abdominal Compartment Syndrome and Percutaneous Needle Decompression in a Woman with Corrosive Injury

Abdominal Compartment Syndrome (ACS) is defined by organ dysfunction caused by intra-abdominal hypertension. Increase in intra-abdominal pressure causes multiple adverse physiologic events and is uniformly fatal if left untreated. We report the case of a 76-year-old woman of pneumoperitoneum due to hydrocholoric acidinduced corrosive injury, leading to ACS with pulseless electrical activity. Emergency needle decompression was done and successfully restored circulation. It reminds possible ACS in patients of pneumoperitoneum and use of percutaneous needle decompression before operation in emergent condition.

Effect of implementing structured communication messages on the clinical outcomes of unconscious patients

Background: Patient communication is one of the most important factors associated with quality of care and patient safety, especially in Intensive Care Units (ICUs). However, relatively little is known about the different aspects of communication with unconscious patients, and the effect of communication and outcome measures. Aim: This study aimed to examine effects of implementing structured communication messages (SCMs) on the clinical outcomes of unconscious patients. Methods: A quasi-experimental design was utilized. Sixty unconscious patients were selected from three ICUs of Emergency Hospital of Mansoura University and two ICUs at Main Hospital of Mansoura University. Patients were randomly allocated into two groups (intervention and control group) 30 patients in each. Four tools were used for data collection: physiological adverse events (PAE) assessment tool including (hyperthermia, hypothermia, tachycardia, bradycardia, hypertension, hypotension, hypovolemia, hypervolemia, desaturation, bradypnea, ventilatory distress, hyperglycemia or hypoglycemia), Full Outline of Un-Responsiveness (FOUR) scale, Behavioural Pain Scale (BPS), and Motor Activity Assessment Scale (MAAS). Results: The implementation of SCMs was associated with a decreased incidence of PAE and a statistically significant positive effect on level of consciousness revealed by FOUR scale. Patients in the intervention group maintained in MAAS level (2-3) (calm, cooperative and responsive to touch). The BPS in intervention group significantly decreased following the application of SCMs than control group. Moreover, the mean duration of mechanical ventilation and length of stay in ICU were significantly shorter in the intervention group than in the control group. Conclusions: The SCMs developed, has been shown to facilitate the communication with the unconscious patients therefore, it is recommended for use in a nurse’s daily routine of unconscious patients.

Clinical effects of specialist and on-call respiratory physiotherapy treatments in mechanically ventilated children: A randomised crossover trial

ObjectivesThe study investigated treatment outcomes when respiratory physiotherapy was delivered by non-respiratory on-call physiotherapists, compared with specialist respiratory physiotherapists. DesignProspective, randomised crossover trial. SettingPaediatric, tertiary care hospital in the United Kingdom. ParticipantsMechanically ventilated children requiring two physiotherapy interventions during a single day were eligible. Twenty two physiotherapists (10 non-respiratory) and 93 patients were recruited. InterventionsPatients received one treatment from a non-respiratory physiotherapist and another from a respiratory physiotherapist, in a randomised order. Treatments were individualised to the patients’ needs, often including re-positioning followed by manual lung inflations, chest wall vibrations and endotracheal suction. Main outcome measuresThe primary outcome was respiratory compliance. Secondary outcomes included adverse physiological events and clinically important respiratory changes (according to an a priori definition). ResultsTreatments delivered to 63 patients were analysed. There were significant improvements to respiratory compliance (mean increase [95% confidence intervals], 0.07 and 0.08ml·cmH2O−1·kg−1 [0.01 to 0.14 and 0.04 to 0.13], p<0.01, for on-call and respiratory physiotherapists’ treatments respectively). Case-by-case, there were fewer clinically important improvements following non-respiratory physiotherapists’ treatments compared with the respiratory physiotherapists’ (n=27 [43%] versus n=40 [63%], p=0.03). Eleven adverse events occurred, eight following non-respiratory physiotherapists’ treatments. ConclusionsSignificant disparities exist in treatment outcomes when patients are treated by non-respiratory on-call physiotherapists, compared with specialist respiratory physiotherapists. There is an urgent need for targeted training strategies, or alternative service delivery models, to be explored. This should aim to address the quality of respiratory physiotherapy services, both during and outside of normal working hours. Clinical Trial Registration numberClinicaltrials.gov, NCT01999426.

Modelling physiological deterioration in post-operative patient vital-sign data

Patients who undergo upper-gastrointestinal surgery have a high incidence of post-operative complications, often requiring admission to the intensive care unit several days after surgery. A dataset comprising observational vital-sign data from 171 post-operative patients taking part in a two-phase clinical trial at the Oxford Cancer Centre, was used to explore the trajectory of patients’ vital-sign changes during their stay in the post-operative ward using both univariate and multivariate analyses. A model of normality based vital-sign data from patients who had a “normal” recovery was constructed using a kernel density estimate, and tested with “abnormal” data from patients who deteriorated sufficiently to be re-admitted to the intensive care unit. The vital-sign distributions from “normal” patients were found to vary over time from admission to the post-operative ward to their discharge home, but no significant changes in their distributions were observed from halfway through their stay on the ward to the time of discharge. The model of normality identified patient deterioration when tested with unseen “abnormal” data, suggesting that such techniques may be used to provide early warning of adverse physiological events.

Repetitive TASER X26 Discharge Resulted in Adverse Physiologic Events with a Dose–Response Relationship Related to the Duration of Discharge in Anesthetized Swine Model

The objectives of our study were to investigate the dose-response relationship of the TASER X26 discharge duration in an anesthetized swine model. Fourteen swines were anesthetized and then exposed to TASER X26 discharge for 5 sec (n = 5) or for 10 sec (n = 6). The sham control group (n = 3) was anesthetized and studied using the same protocol except TASER X26 discharges during the experiments. Hemodynamic parameters were obtained. Blood pressure and total peripheral resistance decreased significantly after TASER discharge and returned to baseline value at 15 min after 5 sec of TASER discharge but did not return to baseline values during the 30-min observation period after 10 sec of TASER discharge. Repetitive TASER X26 discharge resulted in adverse physiologic events with a dose-response relationship related to the duration of TASER X26 discharge in an anesthetized swine model.

A New Era in the ICU

Management of the patient in the intensive care unit requires constant vigilance and monitoring. The nursing staff, and physicians must be readily available to alter therapy in response to adverse physiological changes and life-threatening events. In the face of limited staffing and overwhelming workloads, telemedicine has become a mainstay in ensuring safety for the critically ill patient. Nurses must respond to the challenge to utilize every aspect of this technology, and to become an active partner in improving the utilization of this tool for accessing physician interface and ensuring support when decision-making and immediate actions are required for optimum clinical outcomes.

New considerations for ADT in advanced prostate cancer and the emerging role of GnRH antagonists

Androgen deprivation therapy (ADT) is first-line treatment for metastatic prostate cancer (PCa). Gonadotrophin-releasing hormone (GnRH) agonists are the most commonly used ADT but have several theoretical physiologic disadvantages (e.g. initial testosterone surge, potential microsurges upon repeat administration). Testosterone surge delays the intended serologic endpoint of testosterone suppression and may exacerbate clinical symptoms. GnRH antagonists were developed with a view toward overcoming these potential adverse physiologic events. This review evaluates GnRH agonists and antagonists, assessing the potential future role of antagonists in PCa and strategies to minimize ADT adverse events (AEs). Evidence was identified via PubMed search (by GnRH agent and other ADT-related terms), from review article bibliographies, and authors' therapy area knowledge, with articles included by author consensus. Degarelix shows similar efficacy to a GnRH agonist in achieving and maintaining castration, with faster onset and without testosterone surge/microsurges. Phase III data showed that, in the first treatment year, degarelix displayed a lower risk of PSA failure or death (composite endpoint), lower levels of the bone marker serum alkaline phosphatase (in baseline metastatic disease), and fewer musculoskeletal AEs than the agonist leuprolide. Also, crossing over from leuprolide to degarelix after 1 year reduced the risk of PSA failure or death. ADT displays an AE spectrum which can impact quality of life as well as causing significant morbidities. Strategies to improve ADT tolerability have become increasingly important including: a holistic management approach, improved diet and exercise, more specific monitoring to detect and prevent testosterone depletion toxicities, and intermittent ADT allowing hormonal recovery between treatment periods. Clinical studies suggest possible benefits of GnRH antagonists over agonists based on different mechanisms of action. GnRH antagonists should now be considered as an alternative first-line ADT option in advanced PCa. Intermittent ADT and a holistic treatment approach are promising strategies to improve ADT tolerability.

Mechanisms behind adhesive erythrocytes in sickle‐cell disease

Erythrocytes containing primarily hemoglobin S (SS RBCs) are abnormally adherent to a number of ligands, including normal constituents of the extracellular matrix as well as those present on the surfaces of other blood cells and endothelial cells. However, SS RBCs are not really very different from normal (AA) RBCs, except that they are younger. In general, they express the same range of adhesion receptors, and the levels of expression of these receptors, although increased in some cases, are not sufficient to explain the difference between the adhesivity of SS and AA RBCs. However, SS RBCs have activated adhesion receptors, and the signaling pathways responsible for this activation are also upregulated in SS RBCs. In addition, SS RBCs convey different extracellular signals, which are also likely to affect their adhesion to other blood cells and endothelial cells. Together, SS RBCs induce cell–cell interactions mediated by the B‐CAM/LU, ICAM4 (LW), CD44 (In), CD47, α4β1 integrin, and CD36 adhesion molecules on SS RBCs with target ligands on leukocytes and endothelial cells. Other, as yet unidentified cell surface moieties on SS RBCs are probably also responsible for SS RBC interactions with P‐selectin. Interestingly, at least some of these RBC adhesion receptors may also mediate adhesion and adverse physiologic events in the setting of transfusion of stored normal RBCs. Therefore, understanding the mechanisms behind SS RBC adhesion may offer opportunities for improving both therapy of sickle‐cell disease as well as transfusion practices.

Physiologic Effects of Retinopathy of Prematurity Screening Examinations

Preterm infants weighing less than 1500 g routinely undergo a series of eye examinations to screen for retinopathy of prematurity (ROP). While these examinations are important for the prevention of blindness, infants may suffer adverse physiologic events during and after the examination. The procedure includes administration of mydriatic eye drops that may be absorbed systemically and physical manipulation of the eye that is accompanied by stress and pain. The purpose of the study was to monitor changes in infant health status and adverse physiologic events in the 2 days after ROP eye screening. The study used 50 preterm infants with a mean gestational age of 32 weeks, undergoing their first ROP examination in a NICU located in a university medical center. This pilot study used a prospective, descriptive design. Physiologic changes and illness events were recorded before and for 2 days after the eye examination, using tools that tracked parameters of respiratory, cardiovascular, gastrointestinal, and neurological status. Data were collected directly from daily audits of medical records. McNemar's test for comparing paired proportions and the signed rank test were used for comparing significance of physiologic changes before and after the ROP eye examination. Apnea events increased significantly (P = .04) in the 24- to 48-hour period after the eye examination compared with apnea events before the eye examination. These results were based on 39 infants who were not receiving ventilator support. There was a significant difference in the frequency of oxygen desaturation events between infants with and without apnea (0-24 hours after examination, P < .002; 25-48 hours after examination, P < .001). There were no significant differences in heart rate, cyanosis, gastric residuals, or seizures after the eye examinations. The ROP examinations may be associated with increased apnea, a clinically significant problem. Nursing implications include careful monitoring of infants during and after ROP eye examinations, discharge teaching for caregivers, and continued research on nursing interventions to prevent adverse physiologic events.

Improving UK trauma care: the NCEPOD trauma report

Improving UK trauma care: the NCEPOD trauma report