Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Austin Hopper is active.

Publication


Featured researches published by Austin Hopper.


Journal of Emergency Medicine | 2015

KETAMINE USE FOR ACUTE AGITATION IN THE EMERGENCY DEPARTMENT

Austin Hopper; Gary M. Vilke; Edward M. Castillo; Ashleigh Campillo; Timothy Davie; Michael P. Wilson

BACKGROUND Emergency physicians regularly encounter agitated patients. In extremely agitated and violent patients, the onset of many traditional medications is relatively slow and often requires additional medication. Ketamine is frequently used in emergency departments (EDs) for procedural sedation and intubation, but has recently been suggested as a treatment for acute agitation. OBJECTIVES We sought to examine the use of ketamine in the treatment of acute agitation in an ED setting, including vital sign changes as a result of this medication. METHODS This is a structured review of an historical cohort of patients over 7 years at two university EDs. Patients were included if they received ketamine as treatment for acute agitation. Abstracted data included age, vital signs including hypoxia, any additional medications for agitation, and alcohol/drug intoxication. RESULTS Ketamine was administered for agitation on 32 visits involving 27 patients. Preadministration systolic blood pressure was 131 ± 20 mm Hg, with an average postadministration increase of 17 ± 25 mm Hg. The average baseline heart rate was 98 ± 23 beats/min, with an average increase of 8 ± 17 beats/min. No patients became hypoxic; 62.5% of patients required additional calming medication. Alcohol or drug intoxication was present in 40.6% of patients. CONCLUSIONS We found ketamine was used rarely, but had few major adverse effects on vital signs even in a population with 21.9% alcohol intoxication. However, a high proportion (62.5%) of patients required additional pharmacologic treatment for agitation, implying that administering ketamine is useful only for initial control of severe agitation.


Acta Oncologica | 2017

Associations between volume changes and spatial dose metrics for the urinary bladder during local versus pelvic irradiation for prostate cancer

O. Casares-Magaz; Vitali Moiseenko; Austin Hopper; Niclas Pettersson; Maria Thor; Rick Knopp; Joseph O. Deasy; Ludvig Paul Muren; John Einck

Abstract Background: Inter-fractional variation in urinary bladder volumes during the course of radiotherapy (RT) for prostate cancer causes deviations between planned and delivered doses. This study compared planned versus daily cone-beam CT (CBCT)-based spatial bladder dose distributions, for prostate cancer patients receiving local prostate treatment (local treatment) versus prostate including pelvic lymph node irradiation (pelvic treatment). Material and Methods: Twenty-seven patients (N = 15 local treatment; N = 12 pelvic treatment) were treated using daily image-guided RT (1.8 Gy@43-45 fx), adhering to a full bladder/empty rectum protocol. For each patient, 9-10 CBCTs were registered to the planning CT, using the clinically applied translations. The urinary bladder was manually segmented on each CBCT, 3 mm inner shells were generated, and semi and quadrant sectors were created using axial/coronal cuts. Planned and delivered DVH metrics were compared across patients and between the two groups of treatment (t-test, p < .05; Holm–Bonferroni correction). Associations between bladder volume variations and the dose-volume histograms (DVH) of the bladder and its sectors were evaluated (Spearman’s rank correlation coefficient, rs). Results: Bladder volumes varied considerably during RT (coefficient of variation: 16–58%). The population-averaged planned and delivered DVH metrics were not significantly different at any dose level. Larger treatment bladder volumes resulted in increased absolute volume of the posterior/inferior bladder sector receiving intermediate-high doses, in both groups. The superior bladder sector received less dose with larger bladder volumes for local treatments (rs ± SD: −0.47 ± 0.32), but larger doses for pelvic treatments (rs ± SD: 0.74 ± 0.24). Conclusions: Substantial bladder volume changes during the treatment course occurred even though patients were treated under a full bladder/daily image-guided protocol. Larger bladder volumes resulted in less bladder wall spared at the posterior-inferior sector, regardless the treatment received. Contrary, larger bladder volumes meant larger delivered doses to the superior bladder sector for pelvic RT but smaller doses for local treatments. Graphical Abstract


Journal of Emergency Medicine | 2015

FIRST-GENERATION ANTIPSYCHOTICS ARE OFTEN PRESCRIBED IN THE EMERGENCY DEPARTMENT BUT ARE OFTEN NOT ADMINISTERED WITH ADJUNCTIVE MEDICATIONS

Ashleigh Campillo; Edward M. Castillo; Gary M. Vilke; Austin Hopper; Victoria Ryan; Michael P. Wilson

BACKGROUND Although first-generation antipsychotics (FGAs) have long been used in the emergency department (ED) to treat acute agitation, little is known about how these medications are used in modern clinical practice. In particular, little work has been published about whether ED clinicians administer FGAs with adjunctive medications in accordance with expert guidelines or the prescribing practices of FGAs over time. OBJECTIVES 1) To provide a comparison of the frequency with which FGAs are administered with adjunctive benzodiazepines or anticholinergic medications. 2) To analyze the prescribing trends for FGAs over time, particularly in the years after the U.S. Food and Drug Administration (FDA) black-box warning for droperidol. METHODS This is a structured review of a retrospective cohort of patients receiving haloperidol or droperidol in two EDs over a 7-year period. RESULTS Haloperidol or droperidol was administered on 2833 patient visits during the study period, with haloperidol being administered most often. Adjunctive medications are administered less than half of the time. The use of droperidol has remained relatively static, whereas the use of haloperidol has increased. CONCLUSIONS First-generation antipsychotics are still widely utilized in the ED. When administered, these medications are used with adjunctive medications that may decrease side effects less than half of the time. Droperidol use has remained unchanged in the years after the FDA black-box warning, whereas use of haloperidol has continued to rise.


Physics and Imaging in Radiation Oncology | 2018

A case-control study using motion-inclusive spatial dose-volume metrics to account for genito-urinary toxicity following high-precision radiotherapy for prostate cancer

O. Casares-Magaz; Ludvig Paul Muren; Niclas Pettersson; Maria Thor; Austin Hopper; Rick Knopp; Joseph O. Deasy; Michael Væth; John Einck; Vitali Moiseenko

Graphical abstract


Advances in radiation oncology | 2016

Salvage image-guided radiotherapy to the prostate after cryotherapy failure.

Austin Hopper; Ajay P. Sandhu; J. Kellogg Parsons; Brent S. Rose; John Einck

Purpose Cryotherapy is an option for the primary treatment of localized prostate cancer, along with radical prostatectomy, external beam radiation therapy, and brachytherapy. Although it is known that local recurrence can occur in >20% of patients treated with primary cryotherapy, unfortunately there is a paucity of data on later salvage treatments. The use of external beam radiation therapy is an attractive option after cryotherapy failure, but there is little data on its efficacy and toxicity. We evaluated the biochemical control and complication rates of salvage dose-escalated image guided intensity modulated radiation therapy (IG-IMRT) after cryotherapy failure. Methods and materials Patients who were treated at our institution from 2005 to 2016 were reviewed for those who underwent cryotherapy as initial treatment followed by salvage IGRT. Patients were treated with dose-escalated IG-IMRT using standard treatment margins of 3 mm posterior and 7 mm in all other directions and daily cone beam computed tomography or kv imaging to implanted fiducial markers. Biochemical progression was defined in accordance with the Phoenix consensus conference definition. Results Eight patients were identified as having received post-cryotherapy salvage radiation within the study period. The median total dose was 77.7 Gy (range, 75.6-81.0 Gy). Median follow-up was 55 months (range, 6-88 months). Six patients remained biochemically controlled at the latest follow-up. One patient developed distant metastases after 22 months and one experienced biochemical failure at 30 months with no evidence of distant metastases. No patients experienced acute gastrointestinal toxicities of grade 2 or higher. There were no cases of late gastrointestinal or genitourinary toxicity. Conclusions High-dose IG-IMRT results in high rates of salvage and extremely low rates of serious late toxicity for patients with locally recurrent prostate cancer after cryotherapy. Although the results are encouraging, given the small number of patients in this and other series, we remain cautious with regard to this treatment and believe the use of salvage radiation therapy after cryotherapy warrants further study.


Journal of Emergency Medicine | 2017

Risperidone in the Emergency Setting is Associated with More Hypotension in Elderly Patients

Michael P. Wilson; Kimberly Nordstrom; Austin Hopper; Austin Porter; Edward M. Castillo; Gary M. Vilke


International Journal of Radiation Oncology Biology Physics | 2015

Impact of Pretreatment PSA on Biochemical PFS Following High-Dose Image Guided Post Prostatectomy Radiation Therapy

Austin Hopper; Ajay P. Sandhu; V.E. Chen; John Einck


Physica Medica | 2018

[OA009] Motion inclusive variations in bladder dose surface maps during the course of high-precision radiotherapy for prostate cancer

Hal Clark; O. Casares-Magaz; Niclas Pettersson; Ludvig Paul Muren; Austin Hopper; Rick Knopp; John Einck; Vitali Moiseenko


Journal of Clinical Oncology | 2017

Difference in risk factors associated with biochemical recurrence after salvage RT compared to post-prostatectomy patients with negative margins.

Austin Hopper; Ajay P. Sandhu; John Einck


Annals of Emergency Medicine | 2014

386 Use of Quetiapine in the Emergency Department for Acute Agitation and Associated Physiologic Effects

C. Smith; Austin Hopper; Ashleigh Campillo; Edward M. Castillo; Gary M. Vilke; Michael P. Wilson

Collaboration


Dive into the Austin Hopper's collaboration.

Top Co-Authors

Avatar

John Einck

University of California

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Gary M. Vilke

University of California

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Ajay P. Sandhu

University of California

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Rick Knopp

University of California

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

C. Smith

University of California

View shared research outputs
Researchain Logo
Decentralizing Knowledge