Park, John G.

Point-of-care ultrasound (POCUS) is increasingly becoming integral to clinical practice across many subspecialties. Its value in diagnostics and therapeutics has been validated across various disorders. It is becoming evident that the integration of POCUS in our intensive care units is becoming essential in early diagnostics and interventions that impacts patient outcomes. Therefore, we must train our next generation of intensivists, guided by several established recommendations from multiple societies. To achieve this task, we propose that at least four crucial elements, with full support from the institutional leadership, must be established. These include sufficient number of trained staff, a comprehensive curriculum, an educational platform, and a continuous professional development program. In establishing such a program, the potential harm of misinterpretation leading to mismanagement should be mitigated.

AbstractBackgroundSleep’s crucial role in maintaining brain health is increasingly recognized, particularly due to the rising prevalence of neurodegenerative diseases. It not only supports cognitive function but also aids in clearing brain metabolic waste through cerebrospinal fluid (CSF) dynamics. During sleep, especially in the non‐rapid eye movement (NREM) phase, CSF flow increases, essential for removing neurotoxic substances like amyloid‐beta proteins. This study explores the link between sleep respiratory patterns and CSF flow promotion.MethodElectroencephalography (EEG), and functional magnetic resonance imaging (fMRI) were simultaneously acquired during sleep from Gu, et al. (n = 29) (Gu et al. 2022). Respiration, measured via a respiratory belt, calculated respiratory volume (RV) as the standard deviation within a 5 second sliding window. EEG data processed delta band power (1‐4Hz) averaged across channels. Parcellated fMRI data using the brain template followed by the calculation of the averaged gray matter (GM) blood‐oxygen‐level‐dependent (BOLD) signal using the GM mask. CSF inflow was manually extracted from the fMRI’s bottom slice at the foramen magnum level. Subsequently, all signals were temporally aligned to the peak of the CSF inflow signal.ResultAt the time of CSF inflow (time = 0 sec. in the Figure 1A‐D), we observed an earlier increase in RV and EEG delta power, followed by changes in the GM BOLD signal (Figure 1). EEG and RV changes preceded the BOLD signal changes, which, in turn, preceded changes in CSF flow. Sensitivity to detect RV involvement during MRI varied with the placement of the respiratory belt, being least sensitive on the chest and more on the abdomen.ConclusionThese findings raise an interesting question on the role respiratory patterns during sleep, particularly in the NREM phase. Speculatively, RV change may influence CSF circulation during NREM sleep (Figure 1E). This enhancement in CSF flow is crucial for the clearance of metabolic waste from the brain, potentially reducing the risk of neurodegenerative diseases. Our findings indicate that respiratory volume may serve as a significant marker for CSF circulation during sleep.

AbstractBackgroundThe cardiac and respiratory cycles have been suggested as major drivers of cerebrospinal fluid(CSF) flow. The glymphatic system, one of the mechanisms for the clearance of amyloid‐beta and tau proteins, relies heavily on the movement(flow) of the CSF, and thus, investigating the forces that modulate the CSF flow is essential for understanding the glymphatic flux. Because breathing is trainable through exercise and self‐directed methods, various breathing methods may enhance the CSF flow.MethodReal‐time phase‐contrast MRI(pc‐MRI) was used to measure the CSF flow at the foramen magnum on a 3T. Fast resting‐state fMRI(rsfMRI;TR400ms) was conducted on a compact 3T. Under an IRB‐approved protocol, participants were instructed to breathe slowly and deeply, and subsequently switch to their spontaneous breathing. For rsfMRI data preprocessing, we performed motion correction, skull stripping, spatial smoothing(4mm), temporal filtering(0.01 to 0.1Hz), and linear and quadratic temporal trends removal. fMRI time courses were then normalized to Z‐score at each voxel before being averaged. On the pcMRI, the phase was summed in a CSF region‐of‐interest and plotted vs time. Additionally, we confirmed for possible confounding effects such as head motion or motion‐induced susceptibility changes.ResultrsfMRI findings showed that deep breathing promoted large oscillations in the CSF flow in the ventricles, while spontaneous breathing did not(Figure 1). Additionally, deep breathing resulted in large oscillations in lobar cortical regions. Similar results were observed in the pcMRI, with larger CSF velocity through the foramen magnum during the deep breathing compared to the spontaneous breathing(Figure 2A‐B). The cumulative summation result showed that the volume of CSF flow was increased during deep breathing(Figure 2C).ConclusionThis study provides new evidence that slow and deep breathing promotes CSF flow and global brain BOLD signal, which may be useful in promoting circulation in the brain. The study’s findings also open new avenues for research in the field of neurovascular coupling and mechanisms associated with glymphatic clearance. As hampered CSF flow and/or worsen glymphatic clearance have been shown to associate with pathological aging and dementia, including Alzheimer’s disease and Parkinson’s disease, future research is needed explore the potential of breathing training methods as a non‐pharmacological intervention to support brain health.

Abstract Background The medical intensive care unit (MICU) offers rich resident learning opportunities, but traditional teaching strategies can be difficult to employ in this fast-paced, high-acuity environment. Resident perspectives of learning within this environment may improve our understanding of the common challenges residents face and inform novel approaches to transform the MICU educational experience. Objective We conducted a qualitative study of internal medicine residents to better understand their approach to learning the critical care activities that they are entrusted to perform in the MICU. Methods Using a thematic analysis approach, we conducted six focus group interviews with 15 internal medicine residents, separated by postgraduate year. A trained investigator led each interview, which was audio-recorded and transcribed verbatim for analysis. Our diverse research team, representing different career stages across the continuum of learning to minimize interpretive bias, identified codes and subsequent themes inductively. We refined these themes through group discussion and sensitizing social learning theory concepts using Wenger’s community of practice and organized them to create learner archetypes and a conceptual framework of resident learning in the MICU. Results We identified three thematic resident learning categories: learning goals and motivation, clinical engagement, and interprofessional collaboration. We distinguished three learner archetypes, the novice, experiential learner, and practicing member, to describe progressive resident development within the interprofessional MICU team, the challenges they frequently encounter, and potential teaching strategies to facilitate learning. Conclusion We developed a conceptual framework that describes the resident’s journey to becoming a trusted, collaborating member of the interprofessional MICU team. We identified common developmental challenges residents face and offer educational strategies that may support their progress. These findings should inform future efforts to develop novel teaching strategies to promote resident learning in the MICU.

Objective:To describe the current prescribing practices of direct oral anticoagulants (DOACs) in intensive care unit (ICU) patients and the associated clinical outcomes, including the incidence of major bleeding episodes and the need for intervention (endoscopic, surgical, or interventional radiology guided). Design:Observational, retrospective chart review. Setting and Participants:Single large academic center study. Participants included patients with critical illness who were admitted to the intensive care units (ICU) at Mayo Clinic from January 1st, 2012, until May 4th, 2018. Adult ICU patients with a DOAC (apixaban, rivaroxaban, dabigatran, or edoxaban) listed as one of the active medications at the time of hospital admission were included. Results:37 249 patients in medical and surgical intensive care units were screened for the study period. After excluding patients who did not qualify, 558 unique encounters were included. The median age was 69 (IQR 59-78) years; most patients were male, white Caucasians, and had a median SOFA score of 4. After excluding the patients who had major bleeding episodes in the first 24 hours, 188 (39%) were continued on the same DOAC therapy, 204 (42%) were discontinued without transitioning to another agent, and 95 (20%) were transitioned to another agent. Finally, 410 (84%) were dismissed on DOAC therapy at the end of hospitalization. The difference in the continuation rate of the same DOAC agent beyond 24 hours, discontinuation without transition to an alternate agent, or discontinuation of DOAC with a transition to an alternate anticoagulation agent was not statistically significant ( P = .60). A total of 52 major bleeding events were identified. Gastrointestinal bleeding was the most common bleeding complication [n (%): 34 (65)], followed by intra-abdominal and peri-procedural bleeding [7 (13.5) and 7 (13.5)]. Thirty-three (65%) patients had a major bleeding complication requiring intervention. Conclusions:Our single-center retrospective study describes the current prescribing practices and preliminary outcomes in ICU patients with prehospital use of DOACs. Up to 20% of the patients were transitioned to a different agent within 24 hours of ICU admission, whereas a significant proportion of patients (42%) had anticoagulation discontinued altogether. Most patients who suffered a major bleeding episode required either endoscopic or surgical intervention to control bleeding.

Background: Vitamin D deficiency may increase the risk of severe COVID-19 disease. Objectives: To determine if 25-hydroxyvitamin D [25(OH)D] levels in patients hospitalized for COVID-19 were associated with the clinical outcomes of days on oxygen, duration of hospitalization, ICU admission, need for assisted ventilation, or mortality. Methods: We conducted a retrospective study of 92 patients admitted to the hospital with SARS-CoV-2 infection between April 16, 2020 and October 17, 2020. Multivariable regression was performed to assess the independent relationship of 25(OH)D values on outcomes, adjusting for significant covariates and the hospitalization day the level was tested. Results: About 15 patients (16.3%) had 25(OH)D levels <20 ng/mL. Only 1 patient (3.4%) who had documented vitamin D supplementation prior to admission had 25(OH)D <20 ng/mL. Serum 25(OH)D concentrations were not significantly associated with any of our primary outcomes of days on oxygen, duration of hospitalization, intensive care unit (ICU) admission, need for mechanical ventilation, or mortality in any of the adjusted multivariable models. Adjusting for the hospital day of 25(OH)D sampling did not alter the relationship of 25(OH)D with any outcomes. Conclusion: Vitamin D status was not related to any of the primary outcomes reflecting severity of COVID-19 in hospitalized patients. However, our sample size may have lacked sufficient power to demonstrate a small effect of vitamin D status on these outcomes.

Abstract BackgroundAcute respiratory failure associated with sepsis contributes to higher in-hospital mortality. Intubation and invasive mechanical ventilation is a common rescue procedure. However, the 2016 International Guidelines for Management of Sepsis and Septic Shock does not provide any recommendation on indication nor timing of intubation. Timely intubation may improve outcome. The decision to intubate those patients is often hampered by the fear of further hemodynamic deterioration following intubation. MethodsThis study aimed at evaluating the impact of timely intubation on outcome in sepsis associated respiratory failure. We conducted an ancillary analysis of a prospective registry od adult ICU patients with septic shock admitted to the medical ICU in a tertiary medical center, between April 30th, 2014 and December 31st, 2017. All cases of sepsis with lactate >4 mmol/L, mean arterial pressure <65 mmHg, or vasopressor use after 30 mL/kg fluid boluses and suspected or confirmed infection. Patients who remained hospitalized at 24 hours following sepsis onset were separated into intubated and non-intubated groups. The primary outcome was hospital mortality. Univariate and multivariable analyses were used, adjusted for admission characteristics and stabilization of shock within 6 hours. In a secondary analysis, time-dependent propensity score matching was used to match intubated and non-intubated patients.ResultsWe identified 345 (33%) patients intubated within 24 hours and 707 (67%) not intubated. Intubated patients were younger, transferred more often from an outside facility, had higher severity of illness scores, more lung infection, achieved blood pressure goals more often but less often lactate normalization within 6 hours. The crude in-hospital mortality was higher, 89 (26%) vs. 82 (12%), p<0.001, as were ICU mortality, and ICU and hospital length of stay. After adjustment, intubation showed no effect on hospital mortality but fewer hospital-free days through day 28. After 1:1 propensity score matching, there was no difference in hospital mortality, but fewer hospital-free days in the intubated group. ConclusionsIntubation within 24 hours of sepsis onset was safe and not associated with hospital mortality, but was associated with less 28-day hospital-free days. Intubation should not be discouraged in appropriate patients with septic shock.

Extracorporeal membrane oxygenation (ECMO) is used to treat severe hypoxemic respiratory failure and as a rescue therapy for patients with cardiopulmonary arrest within a narrow window of time. A failure modes and effects analysis (FMEA) was conducted to analyze the clinical and operational processes leading to delays in initiating ECMO. FMEA determined these highest-risk failure modes that were contributing to process failure: (1) ECMO candidacy not determined in time, (2) no or incomplete evaluation for ECMO prior to consult or arrest, (3) ECMO team not immediately available, and (4) cannulation not completed in time. When implemented collectively, a total of 4 interventions addressed more than 95% of the system failures. These interventions were (1) ECMO response pager held by a team required for decision, (2) distribution of institutionally defined inclusion/exclusion criteria, (3) educational training for clinicians consulting the ECMO team, and (4) establishment of a mobile ECMO insertion cart.