Evaluation Challenges for the Application of Extended Reality Devices in Medicine.

Augmented and virtual reality devices are being actively investigated and implemented for a wide range of medical uses. However, significant gaps in the evaluation of these medical devices and applications hinder their regulatory evaluation. Addressing these gaps is critical to demonstrating the devices' safety and effectiveness. We outline the key technical and clinical evaluation challenges discussed during the US Food and Drug Administration's public workshop, "Medical Extended Reality: Toward Best Evaluation Practices for Virtual and Augmented Reality in Medicine" and future directions for evaluation method development. Evaluation challenges were categorized into several key technical and clinical areas. Finally, we highlight current efforts in the standards communities and illustrate connections between the evaluation challenges and the intended uses of the medical extended reality (MXR) devices. Participants concluded that additional research is needed to assess the safety and effectiveness of MXR devices across the use cases.

The Impact of Corticosteroids on Secondary Infection and Mortality in Critically Ill COVID-19 Patients.

BACKGROUND: Corticosteroids are part of the treatment guidelines for COVID-19 and have been shown to improve mortality. However, the impact corticosteroids have on the development of secondary infection in COVID-19 is unknown. We sought to define the rate of secondary infection in critically ill patients with COVID-19 and determine the effect of corticosteroid use on mortality in critically ill patients with COVID-19. STUDY DESIGN AND METHODS: One hundred and thirty-five critically ill patients with COVID-19 admitted to the Intensive Care Unit (ICU) at the University of Maryland Medical Center were included in this single-center retrospective analysis. Demographics, symptoms, culture data, use of COVID-19 directed therapies, and outcomes were abstracted from the medical record. The primary outcomes were secondary infection and mortality. Proportional hazards models were used to determine the time to secondary infection and the time to death. RESULTS: The proportion of patients with secondary infection was 63%. The likelihood of developing secondary infection was not significantly impacted by the administration of corticosteroids (HR 1.45, CI 0.75-2.82, P = 0.28). This remained consistent in sub-analysis looking at bloodstream, respiratory, and urine infections. Secondary infection had no significant impact on the likelihood of 28-day mortality (HR 0.66, CI 0.33-1.35, P = 0.256). Corticosteroid administration significantly reduced the likelihood of 28-day mortality (HR 0.27, CI 0.10-0.72, P = 0.01). CONCLUSION: Corticosteroids are an important and lifesaving pharmacotherapeutic option in critically ill patients with COVID-19, which have no impact on the likelihood of developing secondary infections.

The use of venous Doppler to predict adverse kidney events in a general ICU cohort.

BACKGROUND: Changes in Doppler flow patterns of hepatic veins (HV), portal vein (PV) and intra-renal veins (RV) reflect right atrial pressure and venous congestion; the feasibility of obtaining these assessments and the clinical relevance of the findings is unknown in a general ICU population. This study compares the morphology of HV, PV and RV waveform abnormalities in prediction of major adverse kidney events at 30 days (MAKE30) in critically ill patients. STUDY DESIGN AND METHODS: We conducted a prospective observational study enrolling adult patients within 24 h of admission to the ICU. Patients underwent an ultrasound evaluation of the HV, PV and RV. We compared the rate of MAKE-30 events in patients with and without venous flow abnormalities in the hepatic, portal and intra-renal veins. The HV was considered abnormal if S to D wave reversal was present. The PV was considered abnormal if the portal pulsatility index (PPI) was greater than 30%. We also examined PPI as a continuous variable to assess whether small changes in portal vein flow was a clinically important marker of venous congestion. RESULTS: From January 2019 to June 2019, we enrolled 114 patients. HV abnormalities demonstrate an odds ratio of 4.0 (95% CI 1.4-11.2). PV as a dichotomous outcome is associated with an increased odds ratio of MAKE-30 but fails to reach statistical significance (OR 2.3 95% CI 0.87-5.96), but when examined as a continuous variable it demonstrates an odds ratio of 1.03 (95% CI 1.00-1.06). RV Doppler flow abnormalities are not associated with an increase in the rate of MAKE-30 INTERPRETATION: Obtaining hepatic, portal and renal venous Doppler assessments in critically ill ICU patients are feasible. Abnormalities in hepatic and portal venous Doppler are associated with an increase in MAKE-30. Further research is needed to determine if venous Doppler assessments can be useful measures in assessing right-sided venous congestion in critically ill patients.

A novel method of calculating stroke volume using point-of-care echocardiography.

BACKGROUND: Point-of-care transthoracic echocardiography (POC-TTE) is essential in shock management, allowing for stroke volume (SV) and cardiac output (CO) estimation using left ventricular outflow tract diameter (LVOTD) and left ventricular velocity time integral (VTI). Since LVOTD is difficult to obtain and error-prone, the body surface area (BSA) or a modified BSA (mBSA) is sometimes used as a surrogate (LVOTDBSA, LVOTDmBSA). Currently, no models of LVOTD based on patient characteristics exist nor have BSA-based alternatives been validated. METHODS: Focused rapid echocardiographic evaluations (FREEs) performed in intensive care unit patients over a 3-year period were reviewed. The age, sex, height, and weight were recorded. Human expert measurement of LVOTD (LVOTDHEM) was performed. An epsilon-support vector regression was used to derive a computer model of the predicted LVOTD (LVOTDCM). Training, testing, and validation were completed. Pearson coefficient and Bland-Altman were used to assess correlation and agreement. RESULTS: Two hundred eighty-seven TTEs with ideal images of the LVOT were identified. LVOTDCM was the best method of SV measurement, with a correlation of 0.87. LVOTDmBSA and LVOTDBSA had correlations of 0.71 and 0.49 respectively. Root mean square error for LVOTDCM, LVOTDmBSA, and LVOTDBSA respectively were 13.3, 37.0, and 26.4. Bland-Altman for LVOTDCM demonstrated a bias of 5.2. LVOTDCM model was used in a separate validation set of 116 ideal images yielding a linear correlation of 0.83 between SVHEM and SVCM. Bland Altman analysis for SVCM had a bias of 2.3 with limits of agreement (LOAs) of - 24 and 29, a percent error (PE) of 34% and a root mean square error (RMSE) of 13.9. CONCLUSIONS: A computer model may allow for SV and CO measurement when the LVOTD cannot be assessed. Further study is needed to assess the accuracy of the model in various patient populations and in comparison to the gold standard pulmonary artery catheter. The LVOTDCM is more accurate with less error compared to BSA-based methods, however there is still a percentage error of 33%. BSA should not be used as a surrogate measure of LVOTD. Once validated and improved this model may improve feasibility and allow hemodynamic monitoring via POC-TTE once it is validated.

Mesenchymal stem cells preserve neonatal right ventricular function in a porcine model of pressure overload.

Limited therapies exist for patients with congenital heart disease (CHD) who develop right ventricular (RV) dysfunction. Bone marrow-derived mesenchymal stem cells (MSCs) have not been evaluated in a preclinical model of pressure overload, which simulates the pathophysiology relevant to many forms of CHD. A neonatal swine model of RV pressure overload was utilized to test the hypothesis that MSCs preserve RV function and attenuate ventricular remodeling. Immunosuppressed Yorkshire swine underwent pulmonary artery banding to induce RV dysfunction. After 30 min, human MSCs (1 million cells, n = 5) or placebo (n = 5) were injected intramyocardially into the RV free wall. Serial transthoracic echocardiography monitored RV functional indices including 2D myocardial strain analysis. Four weeks postinjection, the MSC-treated myocardium had a smaller increase in RV end-diastolic area, end-systolic area, and tricuspid vena contracta width (P < 0.01), increased RV fractional area of change, and improved myocardial strain mechanics relative to placebo (P < 0.01). The MSC-treated myocardium demonstrated enhanced neovessel formation (P < 0.0001), superior recruitment of endogenous c-kit+ cardiac stem cells to the RV (P < 0.0001) and increased proliferation of cardiomyocytes (P = 0.0009) and endothelial cells (P < 0.0001). Hypertrophic changes in the RV were more pronounced in the placebo group, as evidenced by greater wall thickness by echocardiography (P = 0.008), increased cardiomyocyte cross-sectional area (P = 0.001), and increased expression of hypertrophy-related genes, including brain natriuretic peptide, ß-myosin heavy chain and myosin light chain. Additionally, MSC-treated myocardium demonstrated increased expression of the antihypertrophy secreted factor, growth differentiation factor 15 (GDF15), and its downstream effector, SMAD 2/3, in cultured neonatal rat cardiomyocytes and in the porcine RV myocardium. This is the first report of the use of MSCs as a therapeutic strategy to preserve RV function and attenuate remodeling in the setting of pressure overload. Mechanistically, transplanted MSCs possibly stimulated GDF15 and its downstream SMAD proteins to antagonize the hypertrophy response of pressure overload. These encouraging results have implications in congenital cardiac pressure overload lesions.

Trauma indices for prediction of acute respiratory distress syndrome.

BACKGROUND: A myriad of trauma indices has been validated to predict probability of trauma survival. We aimed to compare the performance of commonly used indices for the development of the acute respiratory distress syndrome (ARDS). MATERIALS AND METHODS: Historic, observational cohort study of 27,385 consecutive patients admitted to a statewide referral trauma center between July 11, 2003 and October 31, 2011. A validated algorithm was adapted to identify patients with ARDS. Each trauma index was evaluated in logistic regression using the area under the receiver operating characteristic curve. RESULTS: The case rate for ARDS development was 5.8% (1594). The receiver operating characteristics for injury severity score (ISS) had the best discrimination and had an area under the curve of 0.88 (95% confidence interval [CI] = 0.87-0.89). Glasgow coma score (0.71, 95% CI = 0.70-0.73), A Severity Characterization of Trauma (0.86, 95% CI = 0.85-0.87), Revised Trauma Score (0.71, 95% CI = 0.70-0.72) and thorax Abbreviated Injury Score (0.73, 95% CI = 0.72-0.74) performed worse (P < 0.001) and Trauma and Injury Severity Score (0.88, 95% CI = 0.87-0.88) performed equivocally (P = 0.51) in comparison to ISS. Using a cutoff point ISS ≥16, sensitivity and specificity were 84.9% (95% CI = 83.0%-86.6%) and 75.6% (95% CI = 75.1%-76.2%), respectively. CONCLUSIONS: Among commonly used trauma indices, ISS has superior or equivocal discriminative ability for development of ARDS. A cutoff point of ISS ≥16 provided good sensitivity and specificity. The use of ISS ≥16 is a simple method to evaluate ARDS in trauma epidemiology and outcomes research.

Acute respiratory distress syndrome and outcomes after near hanging.

PURPOSE: The purpose of this study is to assess the case rate of acute respiratory distress syndrome (ARDS) after near hanging and the secondary outcomes of traumatic and/or anoxic brain injury and death. Risk factors for the outcomes were assessed. METHOD: The method is a single-center, statewide retrospective cohort study of consecutive patients admitted between August 2002 and September 2011, with a primary diagnosis of nonjudicial "hanging injury." RESULTS: Of 56 patients, 73% were male. The median age was 31 (Interquartile range (IQR), 16-56). Upon arrival, 9% (5/56) did not have a pulse, and 23% (13/56) patients were intubated. The median Glasgow Coma Scale (GCS) was 13 (IQR, 3-15); 14% (8/56) had a GCS = 3. Acute respiratory distress syndrome developed in 9% (5/56) of patients. Traumatic anoxic brain injury resulted in 9% (5/56) of patients. The in-hospital case fatality was 5% (3/56). Lower median GCS (3 [IQR, 3-7] vs 14 [IQR, 3-15]; P = .0003) and intubation in field or in trauma resuscitation unit (100% [5/5] vs 16% [8/51]; P = .0003) were associated with ARDS development. Risk factors of death were GCS = 3 (100% [3/3] vs 9% [5/53]; P = .002), pulselessness upon arrival of emergency medical services (100% [3/3] vs 4% [2/53]; P < .001], and abnormal neurologic imaging (50% [1/2] vs zero; P = .04). CONCLUSIONS: The ARDS case rate after near hanging is similar to the general trauma population. Low GCS and intubation are associated with increased risk of ARDS development. The rate of traumatic and/or anoxic brain injury in this population is low.

Adjunctive virtual reality pain relief after traumatic injury: a proof-of-concept within-person randomized trial.

ABSTRACT: In this study, we hypothesized that immersive virtual reality (VR) environments may reduce pain in patients with acute traumatic injuries, including traumatic brain injuries. We performed a randomized within-subject study in patients hospitalized with acute traumatic injuries, including traumatic brain injury with moderate pain (numeric pain score ≥3 of 10). We compared 3 conditions: (1) an immersive VR environment (VR Blu), (2) a content control with the identical environment delivered through nonimmersive tablet computer (Tablet Blu), and (3) a second control composed of donning VR headgear without content to control for placebo effects and sensory deprivation (VR Blank). We enrolled 60 patients, and 48 patients completed all 3 conditions. Objective and subjective data were analyzed using linear mixed-effects models. Controlling for demographics, baseline pain, and injury severity, we found differences by conditions in relieving pain (F 2,75.43 = 3.32, P = 0.042). VR Blu pain reduction was greater than Tablet Blu (-0.92 vs -0.16, P = 0.043), but VR Blu pain reduction was similar to VR Blank (-0.92 vs -1.24, P = 0.241). VR Blu was perceived as most effective by patients for pain reduction (F 2,66.84 = 16.28, P < 0.001), and changes in measures of parasympathetic activity including heart rate variability (F 2,55.511 = 7.87, P < 0.001) and pupillary maximum constriction velocity (F 2,61.41 = 3.50, 1-tailed P = 0.038) echoed these effects. There were no effects on opioid usage. These findings outlined a potential clinical benefit for mollifying pain related to traumatic injuries.

Pain Control and Anxiolysis After Subarachnoid Hemorrhage Using Immersive Virtual Reality: A Case Report.

Debilitating headache persists after acute aneurysmal subarachnoid hemorrhage (SAH). Despite high prevalence, little is known regarding optimal treatment strategies for SAH-related headache. Nonpharmacologic adjunctive therapies are emerging as tools to help treat pain and limit opioid exposure in the hospital. Virtual reality (VR) is an immersive audiovisual experience that has been shown to reduce pain perception in other patient populations. The role of VR in acute brain injury is unknown. Here we report a patient with SAH who suffered from persistent headache during her hospitalization despite escalation of analgesic pharmacotherapy. A trial of VR was used as an adjunct to medication over four days. The patient reported subjective improvement in pain and anxiety. VR may provide additional analgesia and anxiolysis over pharmacologic measures alone and warrants further study in patients with acute brain injury.

Educational Intervention for Management of Acute Trauma Pain: A Proof-of-Concept Study in Post-surgical Trauma Patients.

Objective: Despite years of research and the development of countless awareness campaigns, the number of deaths related to prescription opioid overdose is steadily rising. Often, naive patients undergoing trauma-related surgery are dispensed opioids while in the hospital, resulting in an escalation to long-term opioid misuses. We explored the impact of an educational intervention to modify perceptions of opioid needs at the bedside of trauma inpatients in post-surgery pain management. Materials and Methods: Twenty-eight inpatients with acute post-surgical pain completed this proof-of-concept study adopting an educational intervention related to opioids and non-pharmacological strategies in the context of acute post-surgical pain. An education assessment survey was developed to measure pre- and post-education perceptions of opioid needs to manage pain. The survey statements encompassed the patient's perceived needs for opioids and other pharmacological and non-pharmacological therapeutics to manage acute pain. The primary outcome was the change in the patient's perceived need for opioids. The secondary (explorative) outcome was the change in Morphine Milligram Equivalents (MME) used on the day of the educational intervention while inpatients and prescribed at the time of the hospital discharge. Results: After the educational intervention, patients reported less agreement with the statement, "I think a short course of opioids (less than 5 days) is safe." Moreover, less agreement on using opioids to manage trauma-related pain was positively associated with a significant reduction in opioids prescribed at discharge after the educational intervention. The educational intervention might have effectively helped to cope with acute trauma-related pain while adjusting potential unrealistic expectancies about pain management and, more in general, opioid-related needs. Conclusion: These findings suggest that trauma patients' expectations and understanding of the risks associated with the long-term use of opioids can be modified by a short educational intervention delivered by health providers during the hospitalization. Establishing realistic expectations in managing acute traumatic pain may empower patients with the necessary knowledge to minimize the potential of continuous long-term opioid use, opioid misuse, and the development of post-trauma opioid abuse and/or addiction.

Transthoracic focused rapid echocardiographic examination: real-time evaluation of fluid status in critically ill trauma patients.

BACKGROUND: A transthoracic focused rapid echocardiographic evaluation (FREE) was developed to answer specific questions about treatment direction regarding the use of fluid versus ionotropes in trauma patients. Our objective was to evaluate the clinical utility of the information obtained by this diagnostic test. METHODS: The FREE was performed by an ultrasonographer or an intensivist and interpreted by a surgical intensivist using a full service portable echo machine (Vivid i; GE Healthcare). The clinical team ordering the examination was surveyed before and after the test was performed. RESULTS: During a 9-month study period, the FREE was performed in 53 patients admitted to our trauma critical care units. In 80% of patients, an estimated ejection fraction was obtained. Moderate and severe left ventricular dysfunction was diagnosed in 56% of patients, and right heart dysfunction was found in 25% of the patients. Inferior vena cava (IVC) diameter and IVC respiratory variation was visualized in 80% of patients. In 87% (46 of 53), the FREE was able to answer the clinical question asked by the primary team. Strikingly, in 54% of patients, the plan of care was modified as a result of the FREE examination. CONCLUSIONS: IVC diameter and IVC respiratory variation was able to be obtained in the majority of cases, giving an estimate of fluid status. Estimation of ejection fraction was useful in guiding the treatment plan regarding the requirement of fluid boluses versus ionotropic support. We conclude that the FREE can provide meaningful data in difficult to image critically ill trauma patients.

Use of Ultrasound to Assess Hemodynamics in Acutely Ill Patients.

Early diagnosis of AKI and preventive measures can likely decrease the severity of the injury and improve patient outcomes. Current hemodynamic monitoring variables, including BP, heart and respiratory rates, temperature, and oxygenation status, have been used to identify patients at high risk for AKI. Despite the widespread use of such variables, their ability to accurately and timely detect patients who are high risk has been questioned. Therefore, there is a critical need to develop and validate tools that can measure new and more kidney-specific hemodynamic and laboratory variables, potentially assisting with AKI risk stratification, implementing appropriate and timely preventive measures, and hopefully improved outcomes. The new ultrasonography techniques provide novel insights into kidney hemodynamics and potential management and/or therapeutic targets. Contrast-enhanced ultrasonography; Doppler flow patterns of hepatic veins, portal vein, and intrakidney veins; and ultrasound elastography are among approaches that may provide such information, particularly related to vascular changes in AKI, venous volume excess or congestion, and fluid tolerance. This review summarizes the current state of these techniques and their relevance to kidney hemodynamic management.

Surgical Intensivist-Led Training in Critical Care Ultrasound Improves Performance.

BACKGROUND: Critical care ultrasound (CCUS) is essential in modern practice, with CCUS including cardiac and noncardiac ultrasound. The most effective CCUS training is unknown, with a diverse skill set and knowledge needed for competence. The objective of this project was to evaluate the effect of a surgical intensivist-led training program on CCUS competence in critical care fellows. METHODS: This was a single institution retrospective review from 2016 to 2018 at the R Adams Cowley Shock Trauma Center. Our yearlong surgical intensivist (SI)-led CCUS training program for critical care fellows includes a daylong CCUS training class, CCUS lectures, a CCUS rotation, and bedside CCUS instruction during rotations. Fellows take a knowledge test and skills test before (pretest) and after (posttest) this program. Critical care ultrasound skill was graded on a scale from 1-5, with 4 (minimal help) or 5 (no help) considered competent. Emergency medicine, surgery, and medicine-trained critical care fellows were included. RESULTS: Forty-two critical care fellows were included. Mean posttest scores increased significantly for 21/22 (96%) of skills tested and for 14/30 (47%) of knowledge questions compared to pretest scores. The mean composite skill score increased from 3.25 to 4.82 from pretest to posttest (P < .001). The mean composite knowledge score increased from 60% to 80% from pretest to posttest (P < .001). CONCLUSION: SI-led training improves CCUS competence and knowledge despite the breadth of CCUS.

Adjunctive virtual reality pain relief following traumatic injury: protocol for a randomised within-subjects clinical trial.

INTRODUCTION: The annual mortality and national expense of the opioid crisis continue to rise in the USA (130 deaths/day, $50 billion/year). Opioid use disorder usually starts with the prescription of opioids for a medical condition. Its risk is associated with greater pain intensity and coping strategies characterised by pain catastrophising. Non-pharmacological analgesics in the hospital setting are critical to abate the opioid epidemic. One promising intervention is virtual reality (VR) therapy. It has performed well as a distraction tool and pain modifier during medical procedures; however, little is known about VR in the acute pain setting following traumatic injury. Furthermore, no studies have investigated VR in the setting of traumatic brain injury (TBI). This study aims to establish the safety and effect of VR therapy in the inpatient setting for acute traumatic injuries, including TBI. METHODS AND ANALYSIS: In this randomised within-subjects clinical study, immersive VR therapy will be compared with two controls in patients with traumatic injury, including TBI. Affective measures including pain catastrophising, trait anxiety and depression will be captured prior to beginning sessions. Before and after each session, we will capture pain intensity and unpleasantness, additional affective measures and physiological measures associated with pain response, such as heart rate and variability, pupillometry and respiratory rate. The primary outcome is the change in pain intensity of the VR session compared with controls. ETHICS AND DISSEMINATION: Dissemination of this protocol will allow researchers and funding bodies to stay abreast in their fields through exposure to research not otherwise widely publicised. Study protocols are compliant with federal regulation and University of Maryland Baltimore's Human Research Protections and Institutional Review Board (protocol number HP-00090603). Study results will be published on completion of enrolment and analysis, and deidentified data can be shared by request to the corresponding author. TRIAL REGISTRATION NUMBER: NCT04356963; Pre-results.

Virtual reality: physiological and behavioral mechanisms to increase individual pain tolerance limits.

ABSTRACT: Immersive virtual reality (VR) consists of immersion in artificial environments through the use of real-time render technologies and the latest generation devices. The users feel just as immersed as they would feel in an everyday life situation, and this sense of presence seems to have therapeutic potentials. However, the VR mechanisms remain only partially known. This study is novel in that, for the first time in VR research, appropriate controls for VR contexts, immersive characteristics (ie, control VR), and multifaceted objective and subjective outcomes were included in a within-subject study design conducted on healthy participants. Participants received heat thermal stimulations to determine how VR can increase individual heat-pain tolerance limits (primary outcome) measured in degrees Celsius and seconds while recording concurrent autonomic responses. We also assessed changes in pain unpleasantness, mood, situational anxiety, and level of enjoyment (secondary outcomes). The VR induced a net gain in heat-pain tolerance limits that was paralleled by an increase of the parasympathetic responses. VR improved mood, situational anxiety, and pain unpleasantness when participants perceived the context as enjoyable, but these changes did not influence the increases in pain tolerance limits. Distraction increased pain tolerance limits but did not induce such mood and physiological changes. Immersive VR has been anecdotally applied to improve acute symptoms in contexts such as battlefield, emergency, and operating rooms. This study provides a mechanistic framework for VR as a low-risk, nonpharmacological intervention, which regulates autonomic, affective (mood and situational anxiety), and evaluative (subjective pain and enjoyment ratings) responses associated with acute pain.

Ultrasonographic inferior vena cava diameter response to trauma resuscitation after 1 hour predicts 24-hour fluid requirement.

BACKGROUND: Identification of occult hypovolemia in trauma patients is difficult. We hypothesized that in acute trauma patients, the response of ultrasound-measured minimum inferior vena cava diameter (IVCDMIN), IVC Collapsibility Index (IVCCI), minimum internal jugular diameter (IJVDMIN) or IJV Collapsibility Index (IJVCI) after up to 1 hour of fluid resuscitation would predict 24-hour resuscitation intravenous fluid requirements (24FR). METHODS: An NTI-funded, American Association for the Surgery of Trauma Multi-Institutional Trials Committee prospective, cohort trial was conducted at four Level I Trauma Centers. Major trauma patients were screened for an IVCD of 12 mm or less or IVCCI of 50% or less on initial focused assessment sonographic evaluations for trauma. A second IVCD was obtained 40 minutes to 60 minutes later, after standard-of-care fluid resuscitation. Patients whose second measured IVCD was less than 10 mm were deemed nonrepleted (NONREPLETED), those 10 mm or greater were repleted (REPLETED). Prehospital and initial resuscitation fluids and 24FR were recorded. Demographics, Injury Severity Score, arterial blood gasses, length of stay, interventions, and complications were recorded. Means were compared by ANOVA and categorical variables were compared via χ. Receiver operating characteristic curves analysis was used to compare the measures as 24FR predictors. RESULTS: There were 4,798 patients screened, 196 were identified with admission IVCD of 12 mm or IVCCI of 50% or less, 144 were enrolled. There were 86 REPLETED and 58 NONREPLETED. Demographics, initial hemodynamics, or laboratory measures were not significantly different. NONREPLETED had smaller IVCD (6.0 ± 3.7 mm vs. 14.2 ± 4.3 mm, p < 0.001) and higher IVCCI (41.7% ± 30.0% vs. 13.2% ± 12.7%, p < 0.001) but no significant difference in IJVD or IJVCCI. REPLETED had greater 24FR than NONREPLETED (2503 ± 1751 mL vs. 1,243 ± 1,130 mL, p = 0.003). Receiver operating characteristic analysis indicates IVCDMIN predicted 24FR (area under the curve [AUC], 0.74; 95% confidence interval [CI], 0.64-0.84; p < 0.001) as did IVCCI (AUC, 0.75; 95% CI, 0.65-0.85; p < 0.001) but not IJVDMIN (AUC, 0.48; 95% CI, 0.24-0.60; p = 0.747) or IJVCI (AUC, 0.54; 95% CI, 0.42-0.67; p = 0.591). CONCLUSION: Ultrasound assessed IVCDMIN and IVCCI response initial resuscitation predicts 24-hour fluid resuscitation requirements. LEVEL OF EVIDENCE: Diagnostic tests or criteria, level II.

Relieving acute pain (RAP) study: a proof-of-concept protocol for a randomised, double-blind, placebo-controlled trial.

INTRODUCTION: Physicians and other prescribing clinicians use opioids as the primary method of pain management after traumatic injury, despite growing recognition of the major risks associated with usage for chronic pain. Placebos given after repeated administration of active treatments can acquire medication-like effects based on learning mechanisms. This study hypothesises that dose-extending placebos can be an effective treatment in relieving clinical acute pain in trauma patients who take opioids. METHODS AND ANALYSIS: The relieving acute pain is a proof-of-concept randomised, placebo-controlled, double-blinded, single-site study enrolling 159 participants aged from 18 to 65 years with one or more traumatic injuries treated with opioids. Participants will be randomly assigned to three different arms. Arm 1 will receive the full dose of opioids with non-steroidal anti-inflammatory drugs (NSAIDs). Arm 2 will receive the 50% overall reduction in opioid dosage, dose-extending placebos and NSAIDs. Arm 3 (control) will receive NSAIDs and placebos. The trial length will be 3 days of hospitalisation (phase I) and 2-week, 1-month, 3-month and 6-month follow-ups (exploratory phase II). Primary and secondary outcomes include feasibility and acceptability of the study. Pain intensity, functional pain, emotional distress, rates of rescue therapy requests and patient-initiated medication denials will be collected. ETHICS AND DISSEMINATION: All activities associated with this protocol are conducted in full compliance with the Institutional Review Board policies and federal regulations. Publishing this study protocol will enable researchers and funding bodies to stay up to date in their fields by providing exposure to research activity that may not otherwise be widely publicised. DATE AND PROTOCOL VERSION IDENTIFIER: 3/6/2019 (HP-00078742). TRIAL REGISTRATION NUMBER: NCT03426137.

Echo is a good, not perfect, measure of cardiac output in critically ill surgical patients.

BACKGROUND: Compared with a pulmonary artery catheter (PAC), transthoracic echocardiography (TTE) has been shown to have good agreement in cardiac output (CO) measurement in nonsurgical populations. Our hypothesis is that the feasibility and accuracy of CO measured by TTE (CO-TTE), relative to CO measured by PAC thermodilution (CO-PAC), is different in surgical intensive care unit patients (SP) and nonsurgical patients (NSP). METHODS: Surgical patients with PAC for hemodynamic monitoring and NSP undergoing right heart catheterization were prospectively enrolled. Cardiac output was measured by CO-PAC and CO-TTE. Pearson coefficients were used to assess correlation. Bland-Altman analysis was used to determine agreement. RESULTS: Over 18 months, 84 patients were enrolled (51 SP, 33 NSP). Cardiac output TTE could be measured in 65% (33/51) of SP versus 79% (26/33) of NSP; p = 0.17. Inability to measure the left ventricular outflow tract diameter was the primary reason for failure in both groups; 94% (17/18) in SP versus 86% (6/7) NSP; p = 0.47. Velocity time integral could be measured in all patients. In both groups, correlation between PAC and TTE measurement was strong; SP (r = 0.76; p < 0.0001), NSP (r = 0.86; p < 0.0001). Bland-Altman analysis demonstrated bias of -0.1 L/min, limits of agreement of -2.5 and +2.3 L/min, percentage error (PE) of 40% for SP, and bias of +0.4 L/min, limits of agreement of -1.8 and +2.5 L/min, and PE of 40% for NSP. CONCLUSION: There was strong correlation and moderate agreement between TTE and PAC in both SP and NSP. In both patient populations, inability to measure the left ventricular outflow tract diameter was a limiting factor. LEVEL OF EVIDENCE: Diagnostic tests or criteria, level III.

Graduating Surgical Residents Lack Competence in Critical Care Ultrasound.

OBJECTIVE: Ultrasound provides accessible imaging for bedside diagnostics and procedural guidance, but may lead to misdiagnosis in untrained users. The main objective of this study was to determine observed and self-perceived competence with critical care ultrasound in graduated general surgery residents. DESIGN: The design of this study was a retrospective review. Ultrasound training program records were reviewed for number of prior ultrasound examinations performed, self-perceived competence, observed competence on faculty examinations, and intended future use of individual critical care ultrasound examinations. SETTING: This study was undertaken at the R Adams Cowley Shock Trauma Center, which is a tertiary care center in Baltimore, MD. PARTICIPANTS: Graduated general surgery residents were identified at the beginning of their surgical critical care fellowship at our institution, and were included if they participated in our critical care ultrasound education program. Fifteen graduated general surgery residents were included. RESULTS: Prior ultrasound experience ranged from 100% for focused assessment of sonography for trauma (FAST) to 13.3% for advanced cardiac assessment. Self-perceived competence ranged from 46.7% with FAST to 0% for advanced cardiac assessment. Observed competence ranged from 20.0% for FAST examinations to 0% for basic cardiac assessment, advanced cardiac assessment, and inferior vena cava (IVC) assessment. All participants intended to use ultrasound in the future for FAST, pneumothorax detection and basic cardiac assessment, and 86.7% for IVC assessment and advanced cardiac assessment. Of participants with self-perceived competence, 28.6% had observed competence with FAST, 0% with IVC assessment, and 100% with pneumothorax detection. CONCLUSIONS: Graduated general surgery residents are not competent in multiple critical care ultrasound examinations despite universally planning to use critical care ultrasound in future practice. Current exposure to ultrasound in residency may give a false sense of competency with ultrasound use. A standardized ultrasound curriculum is an urgent need for general surgery training.