Elimination of Emergency Department Ambulance Divert during the COVID-19 Pandemic Was Not Associated with an Increase in the Average Number of Ambulance Arrivals per Day.

INTRODUCTION: During the COVID-19 pandemic, ambulance divert in our EMS system reached critical levels. We hypothesized that eliminating ambulance divert would not be associated with an increase in the average number of daily ambulance arrivals. Our study objective was to quantify the EMS and emergency department (ED) effects of eliminating ambulance divert during the COVID-19 pandemic. METHODS: Regional hospital divert data were obtained for the 10-county Twin Cities metro from MNTrac, a state-supported online system designed to allow hospitals to indicate their divert status to EMS. ED metrics are reported for a single Level I trauma center and were obtained by a deidentified data pull from our electronic medical record covering the 12 months prior to the elimination of divert (2021) and the 12 months after divert elimination (2022). The decision to eliminate divert occurred in November 2021, based on data available through October, with an implementation date of January 2022. The primary study outcome was to quantify the effect of the elimination of divert on the number of ambulances arriving per day at the study hospital. RESULTS: Regional utilization of ambulance divert increased steadily by 859% from January to October 2021 when 355 individual divert events occurred, totaling 809 h (34 days). There was no significant difference in the number of ambulances that arrived to the study hospital in 2021 (30,774) vs 2022 (30,421) p = 0.15. As compared to 2021, in 2022 there was no significant increase in mean ambulance arrivals per day (84/day vs 83/day, p = 0.08), time to room Emergency Severity Index level 2 (ESI) patients (28 min vs 28 min, p = 0.90), or time to obtain emergent head CT in acute "code stroke" patients (12 min vs 12 min, p = 0.15). Ambulance turnaround interval in the ED did not appreciably increase (16 min vs 17 min, p = 0.15). CONCLUSION: Elimination of ambulance divert was not associated with increases in the number of mean daily ambulance arrivals or EMS turnaround intervals, delays in ESI 2 patients being placed in beds, or prolonged time to head CT in stroke code patients.

Supraglottic airway devices are associated with asphyxial physiology after prolonged CPR in patients with refractory Out-of-Hospital cardiac arrest presenting for extracorporeal cardiopulmonary resuscitation.

BACKGROUND: Multiple randomized clinical trials have compared specific airway management strategies during ACLS with conflicting results. However, patients with refractory cardiac arrest died in almost all cases without the availability of extracorporeal cardiopulmonary resuscitation (ECPR). Our aim was to determine if endotracheal intubation (ETI) was associated with improved outcomes compared to supraglottic airways (SGA) in patients with refractory cardiac arrest presenting for ECPR. METHODS: We retrospectively studied 420 consecutive adult patients with refractory out-of-hospital cardiac arrest due to shockable presenting rhythms presenting to the University of Minnesota ECPR program. We compared outcomes between patients receiving ETI (n = 179) and SGA (n = 204). The primary outcome was the pre-cannulation arterial PaO2 upon arrival to the ECMO cannulation center. Secondary outcomes included neurologically favorable survival to hospital discharge and eligibility for VA-ECMO based upon resuscitation continuation criteria applied upon arrival to the ECMO cannulation center. RESULTS: Patients receiving ETI had significantly higher median PaO2 (71 vs. 58 mmHg, p = 0.001), lower median PaCO2 (55 vs. 75 mmHg, p < 0.001), and higher median pH (7.03 vs. 6.93, p < 0.001) compared to those receiving SGA. Patients receiving ETI were also significantly more likely to meet VA-ECMO eligibility criteria (85% vs. 74%, p = 0.008). Of patients eligible for VA-ECMO, patients receiving ETI had significantly higher neurologically favorable survival compared to SGA (42% vs. 29%, p = 0.02). CONCLUSIONS: ETI was associated with improved oxygenation and ventilation after prolonged CPR. This resulted in increased rate of candidacy for ECPR and increased neurologically favorable survival to discharge with ETI compared to SGA.

The Minnesota mobile extracorporeal cardiopulmonary resuscitation consortium for treatment of out-of-hospital refractory ventricular fibrillation: Program description, performance, and outcomes.

BACKGROUND: We describe implementation, evaluate performance, and report outcomes from the first program serving an entire metropolitan area designed to rapidly deliver extracorporeal membrane oxygenation (ECMO)-facilitated resuscitation to patients with refractory ventricular fibrillation/ventricular tachycardia (VF/VT) out-of-hospital cardiac arrest (OHCA). METHODS: This observational cohort study analyzed consecutive patients prospectively enrolled in the Minnesota Mobile Resuscitation Consortium's ECMO-facilitated resuscitation program. Entry criteria included: 1) adults (aged 18-75), 2) VF/VT OHCA, 3) no return of spontaneous circulation following 3 shocks, 4) automated cardiopulmonary resuscitation with a Lund University Cardiac Arrest System (LUCAS™), and 5) estimated transfer time of < 30 min. The primary endpoint was functionally favorable survival to hospital discharge with Cerebral Performance Category (CPC) 1 or 2. Secondary endpoints included 3-month functionally favorable survival, program benchmarks, ECMO cannulation rate, and safety. Essential program components included emergency medical services, 3 community ECMO Initiation Hospitals with emergency department ECMO cannulation sites and 24/7 cardiac catheterization laboratories, a 24/7 mobile ECMO cannulation team, and a single, centralized ECMO intensive care unit. FINDINGS: From December 1, 2019 to April 1, 2020, 63 consecutive patients were transported and 58 (97%) met criteria and were treated by the mobile ECMO service. Mean age was 57 ± 1.8 years; 46/58 (79%) were male. Program benchmarks were variably met, 100% of patients were successfully cannulated, and no safety issues were identified. Of the 58 patients, 25/58 (43% [CI:31-56%]) were both discharged from the hospital and alive at 3 months with CPC 1 or 2. INTERPRETATION: This first, community-wide ECMO-facilitated resuscitation program in the US demonstrated 100% successful cannulation, 43% functionally favorable survival rates at hospital discharge and 3 months, as well as safety. The program provides a potential model of this approach for other communities. FUNDING: The Helmsley Charitable Trust.

Effect of System-Wide Interventions on the Assessment and Treatment of Pain by Emergency Medical Services Providers.

BACKGROUND: An estimated 20% of patients arriving by ambulance to the emergency department are in moderate to severe pain. However, the management of pain in the prehospital setting has been shown to be inadequate. Untreated pain may have negative physiologic and psychological consequences. The prehospital community has acknowledged this inadequacy and made treatment of pain a priority. OBJECTIVES: To determine if system-wide pain management improvement efforts (i.e. education and protocol implementation) improve the assessment of pain and treatment with opioid medications in the prehospital setting and to determine if improvements are maintained over time. METHODS: This was a retrospective before and after study of a countywide prehospital patient care database. The study population included all adult patients transported by EMS between February 2004 and February 2012 with a working assessment of trauma or burn. EMS patient care records were searched for documentation of pain scores and opioid administration. Four time periods were examined: 1) before interventions, 2) after pediatric specific pain management education, 3) after pain management protocol implementation, and 4) maintenance phase. Frequencies and 95% confidence intervals were calculated for all patients meeting the inclusion criteria in each time period and Chi-square was used to compare frequencies between time periods. RESULTS: 15,228 adult patients transported by EMS during the study period met the inclusion criteria. Subject demographics were similar between the four time periods. Pain score documentation improved between the time periods but was not maintained over time (13% [95%CI 12-15%] to 32% [95%CI 31-34%] to 29% [95 CI 27-30%] to 19% [95%CI 18-21%]). Opioid administration also improved between the time periods and was maintained over time (7% [95%CI 6-8%] to 18% [95%CI 16-19%] to 24% [95%CI 22-25%] to 23% [95% CI 22-24%]). CONCLUSIONS: In adult patients both pediatric-focused education and pain protocol implementation improved the administration of opioid pain medications. Documentation and assessment of pain scores was less affected by specific pain management improvement efforts.

The frequency and consequences of cardiopulmonary resuscitation performed by bystanders on patients who are not in cardiac arrest.

BACKGROUND: The American Heart Association encourages trained and untrained bystanders to perform, at a minimum, chest compressions on anyone who suddenly collapses. It is possible that people who are not in cardiac arrest may receive bystander cardiopulmonary resuscitation (CPR), from which the potential for injury is unknown. OBJECTIVES: To determine the number of victims who received bystander CPR but were not in cardiac arrest and to identify any injuries resulting from receiving bystander CPR. METHODS: Retrospective review of patient care records from a countywide emergency medical services (EMS) database. All patients treated by EMS between March 2003 and February 2009 who received bystander CPR were queried. Victims who were determined not to be in cardiac arrest upon EMS personnel assessment were identified as likely not in cardiac arrest. Hospital medical records for transported patients were reviewed for injuries possibly related to CPR. Patient demographics were collected and descriptive statistics were used for analysis. RESULTS: Six hundred seventy-two incidents of bystander CPR occurred, with 77 (11.5%) cases not being identified as cardiac arrests by EMS. Twenty-three percent of the patients were less than 19 years of age. Emergency medical services arrived in less than 6 minutes for 68% of patients. Seventy-two patients were evaluable for injury; of those, 53% were admitted to the intensive care unit. One patient (1.4%) had an injury that was documented in the medical record as possibly CPR-related: rhabdomyolysis. CONCLUSIONS: Bystanders provide CPR for patients who are not in cardiac arrest at a relatively low frequency. Short-duration bystander CPR caused injury in less than 2% of victims. Our results suggest that the benefits of bystander CPR for adults who suddenly collapse outweigh the risk of injury for those not in cardiac arrest.

Unexpectedly high copy number of random integration but low frequency of persistent expression of the Sleeping Beauty transposase after trans delivery in primary human T cells.

We have shown that the Sleeping Beauty (SB) transposon system can mediate stable expression of both reporter and therapeutic genes in human primary T cells and that trans delivery (i.e., transposon and transposase are on separate plasmids) is at least 3-fold more efficient than cis delivery. One concern about trans delivery is the potential for integration of the transposase-encoding sequence into the cell genome with the possibility of continued expression, transposon remobilization, and insertional mutagenesis. To address this concern, human peripheral blood lymphocytes were nucleofected with transposase plasmid and a DsRed transposon. Eighty-eight stable DsRed(+) T cell clones were generated and found to be negative for the transposase-encoding sequence by PCR analysis of genomic DNA. Genomic PCR was positive for transposase in 5 of 15 bulk T cell populations that were similarly transfected and selected for transgene expression where copy numbers were unexpectedly high (0.007-0.047 per cell) by quantitative PCR. Transposase-positive bulk T cells lacked transposase plasmid demonstrated by Hirt (episomal) extracted DNA and showed no detectable transposase by Southern hybridization, Western blot, and quantitative RT-PCR analyses. Cytogenetic and array comparative genomic hybridization analyses of the only identified transposase-positive clone (O56; 0.867 copies per cell) showed no chromosomal abnormality or tumor formation in nude mice although transposon remobilization was detected. Our data suggest that SB delivery via plasmid in T cells should be carried out with caution because of unexpectedly high copy numbers of randomly integrated SB transposase.

Immunofluorescent labeling of cancer marker Her2 and other cellular targets with semiconductor quantum dots.

Semiconductor quantum dots (QDs) are among the most promising emerging fluorescent labels for cellular imaging. However, it is unclear whether QDs, which are nanoparticles rather than small molecules, can specifically and effectively label molecular targets at a subcellular level. Here we have used QDs linked to immunoglobulin G (IgG) and streptavidin to label the breast cancer marker Her2 on the surface of fixed and live cancer cells, to stain actin and microtubule fibers in the cytoplasm, and to detect nuclear antigens inside the nucleus. All labeling signals are specific for the intended targets and are brighter and considerably more photostable than comparable organic dyes. Using QDs with different emission spectra conjugated to IgG and streptavidin, we simultaneously detected two cellular targets with one excitation wavelength. The results indicate that QD-based probes can be very effective in cellular imaging and offer substantial advantages over organic dyes in multiplex target detection.