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Open Access Publications from the University of California

Scholarly Works (6 results)

  • Article
  • Peer Reviewed
Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health, Volume 24, Issue 3 (2023)

Introduction: While windlass-rod style tourniquets stop bleeding in limbs when used by skilled responders, they are less successful in the hands of the untrained or not recently trained public. To improve usability, an academic-industry partnership developed the Layperson Audiovisual Assist Tourniquet (LAVA TQ). The LAVA TQ is novel in design and technology and addresses known challenges in public tourniquet application. A previously published multisite, randomized controlled trial of 147 participants showed that the LAVA TQ is much easier for the lay public to use compared to the Combat Application Tourniquet (CAT). This study evaluates the LAVA TQ’s ability to occlude blood flow in humans compared to the CAT.

Methods: This study was a prospective, blinded, randomized controlled trial to demonstrate the non-inferiority of the LAVA TQ to occlude blood flow when applied by expert users compared to the CAT. The study team enrolled participants in Bethesda, Maryland, in 2022. The primary outcome was the proportion of blood flow occlusion by each tourniquet. The secondary outcome was surface application pressure for each device.

Results: The LAVA TQ and CAT occluded blood flow in all limbs (21 LAVA TQ, 100%; 21 CAT, 100%). The LAVA TQ was applied at a mean pressure of 366 millimeters of mercury (mm Hg) (SD 20 mm Hg), and the CAT at a mean pressure of 386 mm Hg (SD 63 mm Hg) (P = 0.14).

Conclusion: The novel LAVA TQ is non-inferior to the traditional windlass-rod CAT in occluding blood flow in human legs. The application pressure of LAVA TQ is similar to that used in the CAT. The findings of this study, coupled with LAVA TQ’s demonstrated superior usability, make the LAVA TQ an acceptable alternative limb tourniquet.

    Cover page: Blood Vessel Occlusion by the Layperson Audiovisual Assist Tourniquet (LAVA TQ) Compared to the Combat Application Tourniquet: Randomized Controlled TrialCreative Commons 'BY' version 4.0 license
    • Article
    • Peer Reviewed
    Western Journal of Emergency Medicine: Integrating Emergency Care with Population Health, Volume 19, Issue 3 (2018)

    Introduction: In adults with traumatic brain injuries (TBI), hypotension and hypertension at presentation are associated with mortality. The effect of age-adjusted blood pressure in children with TBI has been insufficiently studied. We sought to determine if age-adjusted hypertension in children with severe TBI is associated with mortality.

    Methods: This was a retrospective analysis of the Department of Defense Trauma Registry (DoDTR) between 2001 and 2013. We included for analysis patients <18 years with severe TBI defined as Abbreviated Injury Severity (AIS) scores of the head ≥3. We defined hypertension  as moderate for systolic blood pressures (SBP) between the 95th and 99th percentile for age and gender and severe if greater than the 99th percentile. Hypotension was defined as SBP <90 mmHg for children >10 years or < 70mmHg + (2 x age) for children ≤10 years. We performed multivariable logistic regression and Cox regression to determine if BP categories were associated with mortality. 

    Results: Of 4,990 children included in the DoDTR, 740 met criteria for analysis. Fifty patients (6.8%) were hypotensive upon arrival to the ED, 385 (52.0%) were normotensive, 115 (15.5%) had moderate hypertension, and 190 (25.7%) had severe hypertension. When compared to normotensive patients, moderate and severe hypertension patients had similar Injury Severity Scores, similar AIS head scores, and similar frequencies of neurosurgical procedures. Multivariable logistic regression demonstrated that hypotension (odd ratio [OR] 2.85, 95 confidence interval [CI] 1.26-6.47) and severe hypertension (OR 2.58, 95 CI 1.32-5.03) were associated with increased 24-hour mortality. Neither hypotension (Hazard ratio (HR) 1.52, 95 CI 0.74-3.11) nor severe hypertension (HR 1.65, 95 CI 0.65-2.30) was associated with time to mortality. 

    Conclusion: Pediatric, age-adjusted hypertension is frequent after severe TBI. Severe hypertension is strongly associated with 24-hour mortality. Pediatric, age-adjusted blood pressure needs to be further evaluated as a critical marker of early mortality.

    • 4 supplemental files
    Cover page: Severely Elevated Blood Pressure and Early Mortality in Children with Traumatic Brain Injuries: The Neglected End of the SpectrumCreative Commons 'BY' version 4.0 license
    • Article
    • Peer Reviewed
    UC Davis Previously Published Works (2020)

    Background

    Trauma is the leading cause of death for children and adolescents. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a minimally invasive method of hemorrhage control used primarily in adults. We aimed to characterize REBOA use in pediatric patients.

    Methods

    The American Association for the Surgery of Trauma (AAST) Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) registry was queried for patients <18 years old undergoing REBOA placement (2013-2020). The primary outcome was mortality. Secondary outcomes included injury severity score (ISS), additional interventions, and complications.

    Results

    Eleven patients with a median age of 17 years old had REBOA placed, with a survival rate of 30%. Inflation of the REBOA balloon resulted in a significant increase in systolic blood pressure (SBP) (median SBP pre-REBOA 53 mmHg vs. post-REBOA 110 mmHg, p=0.0007). Patients were severely injured with a median ISS of 29 (interquartile range 16-42). There were no access-site complications. All three surviving patients had a discharge Glasgow Coma Scale of 15.

    Conclusion

    REBOA is used in patients <18 years old, but all reported patients in this registry were adolescents. No REBOA-related complications were reported. Identifying pediatric patients who may benefit from REBOA and modifying currently existing technology for this group of patients is an area of ongoing research.
      Cover page: Nationwide use of REBOA in adolescent trauma patients: An analysis of the AAST AORTA registry
      • Article
      • Peer Reviewed
      UC Davis Previously Published Works (2022)

      Objectives

      To assess recent advances in interfacility critical care transport.

      Data sources

      PubMed English language publications plus chapters and professional organization publications.

      Study selection

      Manuscripts including practice manuals and standard (1990-2021) focused on interfacility transport of critically ill patients.

      Data extraction

      Review of society guidelines, legislative requirements, objective measures of outcomes, and transport practice standards occurred in work groups assessing definitions and foundations of interfacility transport, transport team composition, and transport specific considerations. Qualitative analysis was performed to characterize current science regarding interfacility transport.

      Data synthesis

      The Task Force conducted an integrative review of 496 manuscripts combined with 120 from the authors' collections including nonpeer reviewed publications. After title and abstract screening, 40 underwent full-text review, of which 21 remained for qualitative synthesis.

      Conclusions

      Since 2004, there have been numerous advances in critical care interfacility transport. Clinical deterioration may be mitigated by appropriate patient selection, pretransport optimization, and transport by a well-resourced team and vehicle. There remains a dearth of high-quality controlled studies, but notable advances in monitoring, en route management, transport modality (air vs ground), as well as team composition and training serve as foundations for future inquiry. Guidance from professional organizations remains uncoupled from enforceable regulations, impeding standardization of transport program quality assessment and verification.
        Cover page: Interfacility Transport of Critically Ill Patients
        • Article
        • Peer Reviewed
        UC Davis Previously Published Works (2020)

        Background

        Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an endovascular adjunct to hemorrhage control. Success relies on institutional support and focused training in arterial access. We hypothesized that hospitals with higher REBOA volumes will be more successful than low-volume hospitals at aortic occlusion with REBOA.

        Methods

        This is a retrospective study from the American Association for the Surgery of Trauma Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery Registry from November 2013 to January 2018. Patients aged ≥18 y who underwent REBOA were included. Successful placement of REBOA catheters (defined as hemodynamic improvement with balloon inflation) was compared between high-volume (≥80 cases; two hospitals), mid-volume (10-20 cases; four hospitals), and low-volume (<10 cases; 14 hospitals) hospitals, adjusting for patient factors.

        Results

        Of 271 patients from 20 hospitals, 210 patients (77.5%) had successful REBOA placement. Most patients were male (76.0%) and sustained blunt trauma (78.1%). cardiopulmonary resuscitation (CPR) was ongoing at the time of REBOA placement in 34.5% of patients. Inpatient mortality was 67.4%, unchanged by hospital volume. Multivariable logistic regression found increased odds of successful REBOA placement at high-volume versus low-volume hospitals (odds ratio [OR], 7.50; 95% confidence interval [CI], 2.10-27.29; P = 0.002) and mid-volume versus low-volume hospitals (OR, 7.82; 95% CI, 1.52-40.31; P = 0.014) and decreased odds among patients undergoing CPR during REBOA placement (OR, 0.10; 95% CI, 0.03-0.34; P < 0.001) when adjusting for age, sex, mechanism of injury, prehospital CPR, CPR on admission, transfer status, hospital location of REBOA placement, Glasgow Coma Scale ≤ 13, and injury severity.

        Conclusions

        Hospitals with higher REBOA volumes were more likely to achieve hemodynamic improvement with REBOA inflation. However, mortality and complication rates were unchanged. Independent of hospital volume, ongoing CPR is associated with a decreased odds of successful REBOA placement.
          Cover page: Practice, Practice, Practice! Effect of Resuscitative Endovascular Balloon Occlusion of the Aorta Volume on Outcomes: Data From the AAST AORTA Registry
          • Article
          • Peer Reviewed
          UC Davis Previously Published Works (2020)

          Background

          Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an endovascular adjunct to hemorrhage control. Success relies on institutional support and focused training in arterial access. We hypothesized that hospitals with higher REBOA volumes will be more successful than low-volume hospitals at aortic occlusion with REBOA.

          Methods

          This is a retrospective study from the American Association for the Surgery of Trauma Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery Registry from November 2013 to January 2018. Patients aged ≥18 y who underwent REBOA were included. Successful placement of REBOA catheters (defined as hemodynamic improvement with balloon inflation) was compared between high-volume (≥80 cases; two hospitals), mid-volume (10-20 cases; four hospitals), and low-volume (<10 cases; 14 hospitals) hospitals, adjusting for patient factors.

          Results

          Of 271 patients from 20 hospitals, 210 patients (77.5%) had successful REBOA placement. Most patients were male (76.0%) and sustained blunt trauma (78.1%). cardiopulmonary resuscitation (CPR) was ongoing at the time of REBOA placement in 34.5% of patients. Inpatient mortality was 67.4%, unchanged by hospital volume. Multivariable logistic regression found increased odds of successful REBOA placement at high-volume versus low-volume hospitals (odds ratio [OR], 7.50; 95% confidence interval [CI], 2.10-27.29; P = 0.002) and mid-volume versus low-volume hospitals (OR, 7.82; 95% CI, 1.52-40.31; P = 0.014) and decreased odds among patients undergoing CPR during REBOA placement (OR, 0.10; 95% CI, 0.03-0.34; P < 0.001) when adjusting for age, sex, mechanism of injury, prehospital CPR, CPR on admission, transfer status, hospital location of REBOA placement, Glasgow Coma Scale ≤ 13, and injury severity.

          Conclusions

          Hospitals with higher REBOA volumes were more likely to achieve hemodynamic improvement with REBOA inflation. However, mortality and complication rates were unchanged. Independent of hospital volume, ongoing CPR is associated with a decreased odds of successful REBOA placement.
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