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Open Access Publications from the University of California

Scholarly Works (11 results)

  • Article
  • Peer Reviewed
UC San Francisco Previously Published Works (2021)
This review describes the management of mechanical ventilation in patients with acute respiratory distress syndrome, including in those with coronavirus disease 2019. Low tidal volume ventilation with a moderate to high positive end-expiratory pressure remains the foundation of an evidence-based approach. We consider strategies for setting positive end-expiratory pressure levels, the use of recruitment maneuvers, and the potential role of driving pressure. Rescue therapies including prone positioning and extracorporeal membrane oxygenation are also discussed.
    Cover page: Acute Respiratory Distress Syndrome Ventilator Management and Rescue Therapies
    • Article
    • Peer Reviewed
    UC San Francisco Previously Published Works (2020)
      Cover page: Treatment for severe acute respiratory distress syndrome from COVID-19
      • Article
      • Peer Reviewed
      UC Davis Previously Published Works (2020)

      Administrative data can be used to identify cases of postoperative respiratory failure (PRF). We aimed to determine if recent changes to the Agency for Healthcare Research and Quality Patient Safety Indicator 11 (PSI 11) and adoption of clinical documentation improvement programs have improved the validity of PSI 11. We also analyzed reasons why PSI 11 was falsely triggered.

      Cross-sectional study of all eligible discharges using health record data from five academic medical centers between October 1, 2012 and September 30, 2015.

      Of 437 flagged records, 434 (99.3%) were accurately coded and 414 (94.7%) represented true clinical PRF. None of the false positive records involved respiratory failure present on admission. Most (78.3%) false positive records required airway protection but did not have respiratory failure.

      The validity of PSI 11 has improved with recent changes to the code criterion and adoption of clinical documentation improvement programs.

        Cover page: Postoperative respiratory failure: An update on the validity of the Agency for Healthcare Research and Quality Patient Safety Indicator 11 in an era of clinical documentation improvement programs.
        • Article
        • Peer Reviewed
        UC Davis Previously Published Works (2021)

        Postoperative respiratory failure is the most common serious postoperative pulmonary complication, yet little is known about factors that can reduce its incidence. We sought to elucidate modifiable factors associated with respiratory failure that developed within the first 5 d after an elective operation.

        Matched case-control study of adults who had an operation at five academic medical centers between October 1, 2012 and September 30, 2015. Cases were identified using administrative data and confirmed via chart review by critical care clinicians. Controls were matched 1:1 to cases based on hospital, age, and surgical procedure.

        Our total sample (n = 638) was 56.4% female, 71.3% white, and had a median age of 62 y (interquartile range 51, 70). Factors associated with early postoperative respiratory failure included male gender (odds ratio [OR] 1.72, 95% confidence interval [CI] 1.12-2.63), American Society of Anesthesiologists class III or greater (OR 2.85, 95% CI 1.74-4.66), greater number of preexisting comorbidities (OR 1.14, 95% CI 1.004-1.30), increased operative duration (OR 1.14, 95% CI 1.06-1.22), increased intraoperative positive end-expiratory pressure (OR 1.23, 95% CI 1.13-1.35) and tidal volume (OR 1.13, 95% CI 1.004-1.27), and greater net fluid balance at 24 h (OR 1.17, 95% CI 1.07-1.28).

        We found greater intraoperative ventilator volume and pressure and 24-h fluid balance to be potentially modifiable factors associated with developing early postoperative respiratory failure. Further studies are warranted to independently verify these risk factors, explore their role in development of early postoperative respiratory failure, and potentially evaluate targeted interventions.

          Cover page: Risk Factors Associated With Early Postoperative Respiratory Failure: A Matched Case-Control Study.
          • Article
          • Peer Reviewed
          UC San Francisco Previously Published Works (2021)
          Accurately measuring the risk of pressure injury remains the most important step for effective prevention and intervention. Time-dependent risk factors for pressure injury development in the adult intensive care unit setting are not well understood.

          Objectives

          To develop and validate a dynamic risk prediction model to estimate the risk of developing a hospital-acquired pressure injury among adult ICU patients.

          Design

          ICU admission data were split into training and validation sets. With death as a competing event, both static and dynamic Fine-Gray models were developed to predict hospital-acquired pressure injury development less than 24, 72, and 168 hours postadmission. Model performance was evaluated using Wolbers' concordance index, Brier score, net reclassification improvement, and integrated discrimination improvement.

          Setting and participants

          We performed a retrospective cohort study of ICU patients in a tertiary care hospital located in San Francisco, CA, from November 2013 to August 2017.

          Main outcomes and measures

          Data were extracted from electronic medical records of 18,019 ICU patients (age ≥ 18 yr; 21,220 encounters). Record of hospital-acquired pressure injury data was captured in our institution's incident reporting system. The information is periodically reviewed by our wound care team. Presence of hospital-acquired pressure injury during an encounter and hospital-acquired pressure injury diagnosis date were provided.

          Results

          The dynamic model predicting hospital-acquired pressure injury more than 24 hours postadmission, including predictors age, body mass index, lactate serum, Braden scale score, and use of vasopressor and antifungal medications, had adequate discrimination ability within 6 days from time of prediction (c = 0.73). All dynamic models produced more accurate risk estimates than static models within 26 days postadmission. There were no significant differences in Brier scores between dynamic and static models.

          Conclusions and relevance

          A dynamic risk prediction model predicting hospital-acquired pressure injury development less than 24 hours postadmission in ICU patients for up to 7 days postadmission was developed and validated using a large dataset of clinical variables readily available in the electronic medical record.
            Cover page: Dynamic Risk Prediction for Hospital-Acquired Pressure Injury in Adult Critical Care Patients
            • Article
            • Peer Reviewed
            UC San Francisco Previously Published Works (2021)
            Immunosuppressed patients such as solid organ transplant and hematologic malignancy patients appear to be at increased risk for morbidity and mortality due to coronavirus disease 2019 (COVID-19) caused by SARS coronavirus 2 (SARS-CoV-2). Convalescent plasma, a method of passive immunization that has been applied to prior viral pandemics, holds promise as a potential treatment for COVID-19. Immunocompromised patients may experience more benefit from convalescent plasma given underlying deficits in B and T cell immunity as well as contraindications to antiviral and immunomodulatory therapy. We describe our institutional experience with four immunosuppressed patients (two kidney transplant recipients, one lung transplant recipient, and one chronic myelogenous leukemia patient) treated with COVID-19 convalescent plasma through the Expanded Access Program (NCT04338360). All patients clinically improved after administration (two fully recovered and two discharged to skilled nursing facilities) and none experienced a transfusion reaction. We also report the characteristics of convalescent plasma product from a local blood center including positive SARS-CoV-2 IgG and negative SARS-CoV-2 PCR in all samples tested. This preliminary evidence suggest that convalescent plasma may be safe among immunosuppressed patients with COVID-19 and emphasizes the need for further data on the efficacy of convalescent plasma as either primary or adjunctive therapy for COVID-19.
              Cover page: Treatment of immunocompromised COVID‐19 patients with convalescent plasma
              • Article
              • Peer Reviewed
              UC Davis Previously Published Works (2022)

              Treatment of malignant pancreatic and/or biliary strictures requires tissue diagnosis. Since cytologic brushings at endoscopic retrograde cholangiopancreatography (ERCP) of these strictures has a poor sensitivity for malignancy (30-83%) (see ME Ryan. Gastrointestinal Endoscopy 1991;37(2):139-143; and MB Cohen, Wittchow RJ, Johlin FC, et al. Mod Pathol 1995;8:498-502), tissue diagnosis must be obtained by another route. We report our experience of percutaneous biopsy of malignant pancreatic and/or biliary strictures even when no radiographic mass is present.

              At ERCP, five patients demonstrated pancreatic and/or biliary duct strictures, had atypical cytological brushings, and had their strictures stented. No mass to account for the strictures could be identified on CT. These five patients underwent percutaneous biopsy of the persistent material by CT within 10 days of the ERCP.

              Two patients had adenocarcinoma of the pancreas. One patient had malignant lymphoma and another had cholangiocarcinoma. One patient had inflammatory cells and was followed.

              If the diagnosis of malignancy cannot be made at the time of the ERCP sampling, then our experience suggests that a percutaneous biopsy should be performed even if a mass is not present using the stent as a target.

                Cover page: Outcomes and risk factors for delayed-onset postoperative respiratory failure: a multi-center case-control study by the University of California Critical Care Research Collaborative (UC3RC)
                • Article
                • Peer Reviewed
                UCLA Previously Published Works (2022)

                Background

                Few interventions are known to reduce the incidence of respiratory failure that occurs following elective surgery (postoperative respiratory failure; PRF). We previously reported risk factors associated with PRF that occurs within the first 5 days after elective surgery (early PRF; E-PRF); however, PRF that occurs six or more days after elective surgery (late PRF; L-PRF) likely represents a different entity. We hypothesized that L-PRF would be associated with worse outcomes and different risk factors than E-PRF.

                Methods

                This was a retrospective matched case-control study of 59,073 consecutive adult patients admitted for elective non-cardiac and non-pulmonary surgical procedures at one of five University of California academic medical centers between October 2012 and September 2015. We identified patients with L-PRF, confirmed by surgeon and intensivist subject matter expert review, and matched them 1:1 to patients who did not develop PRF (No-PRF) based on hospital, age, and surgical procedure. We then analyzed risk factors and outcomes associated with L-PRF compared to E-PRF and No-PRF.

                Results

                Among 95 patients with L-PRF, 50.5% were female, 71.6% white, 27.4% Hispanic, and 53.7% Medicare recipients; the median age was 63 years (IQR 56, 70). Compared to 95 matched patients with No-PRF and 319 patients who developed E-PRF, L-PRF was associated with higher morbidity and mortality, longer hospital and intensive care unit length of stay, and increased costs. Compared to No-PRF, factors associated with L-PRF included: preexisiting neurologic disease (OR 4.36, 95% CI 1.81-10.46), anesthesia duration per hour (OR 1.22, 95% CI 1.04-1.44), and maximum intraoperative peak inspiratory pressure per cm H20 (OR 1.14, 95% CI 1.06-1.22).

                Conclusions

                We identified that pre-existing neurologic disease, longer duration of anesthesia, and greater maximum intraoperative peak inspiratory pressures were associated with respiratory failure that developed six or more days after elective surgery in adult patients (L-PRF). Interventions targeting these factors may be worthy of future evaluation.
                  Cover page: Outcomes and risk factors for delayed-onset postoperative respiratory failure: a multi-center case-control study by the University of California Critical Care Research Collaborative (UC<sup>3</sup>RC).
                  • Article
                  • Peer Reviewed
                  UCLA Previously Published Works (2023)
                    Cover page: A LASSO-DERIVED PREDICTIVE MODEL FOR POSTOPERATIVE RESPIRATORY FAILURE IN A HETEROGENEOUS ADULT ELECTIVE SURGERY PATIENT POPULATION
                    • Article
                    • Peer Reviewed
                    UCLA Previously Published Works (2023)

                    Background

                    Postoperative respiratory failure (PRF) is associated with increased hospital charges and worse patient outcomes. Reliable prediction models can help to guide postoperative planning to optimize care, to guide resource allocation, and to foster shared decision-making with patients.

                    Research question

                    Can a predictive model be developed to accurately identify patients at high risk of PRF?

                    Study design and methods

                    In this single-site proof-of-concept study, we used structured query language to extract, transform, and load electronic health record data from 23,999 consecutive adult patients admitted for elective surgery (2014-2021). Our primary outcome was PRF, defined as mechanical ventilation after surgery of > 48 h. Predictors of interest included demographics, comorbidities, and intraoperative factors. We used logistic regression to build a predictive model and the least absolute shrinkage and selection operator procedure to select variables and to estimate model coefficients. We evaluated model performance using optimism-corrected area under the receiver operating curve and area under the precision-recall curve and calculated sensitivity, specificity, positive and negative predictive values, and Brier scores.

                    Results

                    Two hundred twenty-five patients (0.94%) demonstrated PRF. The 18-variable predictive model included: operations on the cardiovascular, nervous, digestive, urinary, or musculoskeletal system; surgical specialty orthopedic (nonspine); Medicare or Medicaid (as the primary payer); race unknown; American Society of Anesthesiologists class ≥ III; BMI of 30 to 34.9 kg/m2; anesthesia duration (per hour); net fluid at end of the operation (per liter); median intraoperative FIO2, end title CO2, heart rate, and tidal volume; and intraoperative vasopressor medications. The optimism-corrected area under the receiver operating curve was 0.835 (95% CI,0.808-0.862) and the area under the precision-recall curve was 0.156 (95% CI, 0.105-0.203).

                    Interpretation

                    This single-center proof-of-concept study demonstrated that a structured query language extract, transform, and load process, based on readily available patient and intraoperative variables, can be used to develop a prediction model for PRF. This PRF prediction model is scalable for multicenter research. Clinical applications include decision support to guide postoperative level of care admission and treatment decisions.
                      Cover page: A Least Absolute Shrinkage and Selection Operator-Derived Predictive Model for Postoperative Respiratory Failure in a Heterogeneous Adult Elective Surgery Patient Population
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