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Weister, Timothy J.

https://orcid.org/0000-0003-1485-2338

Mayo Clinic

Mayo Clinic

Citations 23

DERIVATION OF A MORTALITY PREDICTION MODEL IN CRITICAL CARE PATIENTS WITH CIRRHOSIS AND SEPSIS
Serafim, Laura Piccolo, Choi, Dae Hee , Weister, Timothy J. , Hanson, Andrew C. , Kamath, Patrick S. , Gajic, Ognjen, Simonetto, Douglas A. , Gajic, Ognjen , Moraes, Alice Gallo de

Shock | March 22, 2024 | Volume: 61 | Issue: 3 | Pages: 382-386

10.1097/shk.0000000000002323 Get It

ABSTRACT Objective: The aim of the study is to develop a predictive model for in-hospital mortality in critically ill patients with cirrhosis and sepsis, using clinical and laboratory data. Design: This is a retrospective cohort study. Setting: Medical and mixed intensive care units (ICUs) of a tertiary medical center. Patients: Cirrhotic adults were admitted with sepsis to the ICUs from January of 2007 to May of 2017. Interventions: None. Measurements and Main Results: Of 2,595 ICU admissions of patients with cirrhosis, 277 with first ICU admission for sepsis were included in the analysis, and 37% died in the hospital. Patients who stayed in the ICU for at least 6 h (n = 275) were considered for the multivariate model. Ten-fold cross-validation was used to estimate best parameter values and model performance, and the final model was chosen as the model maximizing area under the receiver-operating characteristic curve. Variables in order of impact were Acute Physiology and Chronic Health Evaluation (APACHE) III score, initial serum lactate, conjugated bilirubin, serum creatinine, model for end-stage liver disease score, age, body mass index, and serum hemoglobin. The final best model from cross-validation presented an area under the receiver operator characteristic curve (AUC) of 0.75, using a cut-point of 50% estimated probability, sensitivity and specificity were 0.46 and 0.90, respectively, with positive predictive value of 0.72 and negative predictive value of 0.74. These results were similar to the APACHE III only model (AUC = 0.74, sensitivity = 0.43, specificity = 0.89, positive predictive value = 0.69, negative predictive value = 0.73). Conclusion: The combination of initial serum lactate level, conjugated bilirubin, initial serum creatinine, model for end-stage liver disease score, age, body mass index, and serum hemoglobin did not yield meaningful improvement in the AUC and did not provide advantage over the APACHE III score for the prediction of in-hospital mortality in critically ill patients with cirrhosis and sepsis.
Postoperative Transfusions after Administration of Delayed Cold-stored Platelets versus Room Temperature Platelets in Cardiac Surgery: A Retrospective Cohort Study
Zec, Simon , Hanson, Andrew C. , Weister, Tim, Stubbs, James R. , Kor, Daryl J. , Warner, Matthew A. , Klompas, Allan M. , Zec, Simon , Stubbs, James, Warner, Matthew A , Weister, Timothy J.

Anesthesiology | May 8, 2023 | Volume: 139 | Issue: 2 | Pages: 153-163

10.1097/aln.0000000000004605 Get It

Background Delayed cold storage of room temperature platelets may extend shelf life from 5 to 14 days. The study hypothesized that the use of delayed cold-stored platelets in cardiac surgery would be associated with decreased postoperative platelet count increments but similar transfusion and clinical outcomes compared to room temperature-stored platelets. Methods This is an observational cohort study of adults transfused with platelets intraoperatively during elective cardiac surgery between April 2020 and May 2021. Intraoperative platelets were either room temperature-stored or delayed cold-stored based on blood bank availability rather than clinical features or provider preference. Differences in transfusion and clinical outcomes, including a primary outcome of allogenic transfusion exposure in the first 24 h postoperatively, were compared between groups. Results A total of 713 patient encounters were included: 529 (74%) room temperature-stored platelets and 184 (26%) delayed cold-stored platelets. Median (interquartile range) intraoperative platelet volumes were 1 (1 to 2) units in both groups. Patients receiving delayed cold-stored platelets had higher odds of allogeneic transfusion in the first 24 h postoperatively (81 of 184 [44%] vs. 169 of 529 [32%]; adjusted odds ratio, 1.65; 95% CI, 1.13 to 2.39; P = 0.009), including both erythrocytes (65 of 184 [35%] vs. 135 of 529 [26%]; adjusted odds ratio, 1.54; 95% CI, 1.03 to 2.29; P = 0.035) and platelets (48 of 184 [26%] vs. 79 of 529 [15%]; adjusted odds ratio, 1.91; 95% CI, 1.22 to 2.99; P = 0.005). There was no difference in the number of units administered postoperatively among those transfused. Platelet counts were modestly lower in the delayed cold-stored platelet group (−9 × 109/l; 95% CI, −16 to −3]) through the first 3 days postoperatively. There were no significant differences in reoperation for bleeding, postoperative chest tube output, or clinical outcomes. Conclusions In adults undergoing cardiac surgery, delayed cold-stored platelets were associated with higher postoperative transfusion utilization and lower platelet counts compared to room temperature-stored platelets without differences in clinical outcomes. The use of delayed cold-stored platelets in this setting may offer a viable alternative when facing critical platelet inventories but is not recommended as a primary transfusion approach. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New
Detecting professional interpreter use among patients with limited English proficiency: Derivation and validation study
Soleimani, Jalal , Marquez, Alberto , Fathma, Sawsan, Weister, Timothy J. , Barwise, Amelia , Barwise, Amelia K

SAGE Open Medicine | May 18, 2022 | Volume: 10 | Issue: No issue available | Pages: No page available

10.1177/20503121221098146 Get It

Objectives: The objective of this derivation and validation study was to develop and validate a search strategy algorithm to detect patients who used professional interpreter services. Methods: We identified all adults who had at least one intensive care unit admission during their hospital stay across the Mayo Clinic Enterprise between 1 January 2015 and 30 June 2020. Three random subsets of 100 patients were extracted from 60,268 patients to develop the search strategy algorithm. Two physician reviewers conducted gold standard manual chart review and any discrepancies were resolved by a third reviewer. These results were compared with the search strategy algorithm each time it was refined. Sensitivity and specificity were calculated during each phase by comparing the search strategy results to the reference gold standard for both derivation cohorts and the final validation cohort. Results: The first search strategy resulted in a sensitivity of 100% and a specificity of 89%. The second revised search strategy achieved a sensitivity of 100% and a specificity of 87%. The final version of the search strategy was applied to the validation subset and sensitivity and specificity were 100% and 89%, respectively. Conclusion: We derived and validated a search strategy algorithm to assess interpreter use among hospitalized patients. Using a search strategy algorithm with high sensitivity and specificity can reduce the time required to abstract data from the electronic medical records compared with manual data abstraction.
Admission Serum Sodium and Osmolarity Are Not Associated with The Occurrence or Outcomes of Acute Respiratory Distress Syndrome in Critically Ill
Weister, Timothy J. , Chalmers, Sarah , Li, Heyi , Bihari, Shailesh , LeMahieu, Allison , Kashyap, Rahul , Lal, Amos , Bersten, Andrew D. , Gajic, Ognjen

No container title available | May 5, 2022 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-1614816/v1 Get It

Abstract ObjectivePrevious studies suggested that hypernatremia or hyperosmolarity may have protective effects in lung injury. We hypothesized that hypernatremia and/or hyperosmolarity would prevent ARDS in those at risk of lung injury and associated with favorable outcomes in ARDS patients.SubjectsAll admissions at medical, surgical, and multidisciplinary intensive care units in Mayo Clinic, Rochester from the year of 2009 to 2019.DesignRetrospective cohort study. The occurrence of ARDS was identified using a validated computerized search strategy. The association between serum sodium/osmolarity and the occurrence of ARDS was analyzed using a multivariable logistic regression model. The relationship between serum sodium/osmolarity and outcomes of ARDS was analyzed using linear and logistic regression models.ResultsAmong 50,498 patients, the serum sodium level on admission did not have a significant association with the occurrence of ARDS, with an adjusted odds ratio of 0.95 [95% CI (0.86, 1.05)]. There was no significant association between calculated serum osmolarity and the occurrence of ARDS, with an adjusted odds ratio of 1.03 [95% CI (1.00, 1.07)]. 1560 patients developed ARDS during the ICU stay. Their serum sodium level did not have a significant association with their outcomes [adjusted estimated difference in 28-day ICU-free days, 0.08 days, 95% CI (-0.85, 1.02), adjusted estimated difference in 28-day ventilator-free days, -0.02, 95% CI (-0.62, 0.58), adjusted odds ratio of 28-day mortality 1.02, 95%CI (0.84, 1.24)]. There was no significant association between their calculated serum osmolarity and their outcomes [adjusted estimated difference in 28-day ICU-free days, -0.26, 95% CI, (-0.63, 0.12); adjusted estimated difference in 28-day ventilator-free days, -0.05, 95% CI (-0.28, 0.19); adjusted odds ratio of 28-day mortality, 1.07, 95% CI (0.99, 1.15)].ConclusionsAdmission serum sodium or serum osmolarity were not associated with the occurrence or outcomes of ARDS in ICU.
Disparities in Hypoxemia Detection by Pulse Oximetry Across Self-Identified Racial Groups and Associations With Clinical Outcomes*
Henry, Nicole , Hanson, Andrew C. , Schulte, Phillip J. , Manento, Megan N., Weister, Timothy J. , Henry, Nicole R, Warner, Nafisseh S. , Warner, Matthew A.

Critical Care Medicine | January 31, 2022 | Volume: 50 | Issue: 2 | Pages: 204-211

10.1097/ccm.0000000000005394 Get It

OBJECTIVES: To assess disparities in hypoxemia detection by pulse oximetry across self-identified racial groups and associations with clinical outcomes. DESIGN: Observational cohort study from May 5, 2018, to December 31, 2020. SETTING: Three academic medical centers in the United States. PATIENTS: Adults greater than or equal to 18 years who self-identified as White, Black, Asian, or American Indian admitted to the ICU or undergoing surgery during inpatient hospitalization with simultaneous measurements of pulse oximetry-estimated oxygen saturation and arterial blood gas-derived oxygen saturation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Multivariable models were employed to assess the relationships between race, occult hypoxemia (i.e., arterial blood gas-derived oxygen saturation < 88% despite pulse oximetry-estimated oxygen saturation ≥ 92%), and clinical outcomes of hospital mortality and hospital-free days. One-hundred twenty-eight–thousand two-hundred eighty-five paired pulse oximetry-estimated oxygen saturation–arterial blood gas-derived oxygen saturation measurements were included from 26,603 patients. Pulse oximetry-estimated oxygen saturation on average overestimated arterial blood gas-derived oxygen saturation by 1.57% (1.54–1.61%). Black, Asian, and American Indian patients were more likely to experience occult hypoxemia during hospitalization (estimated probability 6.2% [5.1–7.6%], 6.6% [4.9–8.8%], and 6.6% [4.4–10.0%], respectively) compared with White patients (3.6% [3.4–3.8%]). Black patients had increased odds of occult hypoxemia compared with White patients after adjustment (odds ratio, 1.65; 1.28–2.14; p < 0.001). Differences in occult hypoxemia between Asian and American Indian patients compared with White patients were not significant after adjustment (odds ratio, 1.53; 0.95–2.47; p = 0.077 and odds ratio, 1.31; 0.80–2.16; p = 0.288, respectively). Occult hypoxemia was associated with increased odds of mortality in surgical (odds ratio, 2.96; 1.20–7.28; p = 0.019) and ICU patients (1.36; 1.03–1.80; p = 0.033). Occult hypoxemia was associated with fewer hospital-free days in surgical (–2.5 d [–3.9 to –1.2 d]; p < 0.001) but not ICU patients (0.4 d [–0.7 to 1.4 d]; p = 0.500). CONCLUSIONS: Occult hypoxemia is more common in Black patients compared with White patients and is associated with increased mortality, suggesting potentially important outcome implications for undetected hypoxemia. It is imperative to validate pulse oximetry with expanded racial inclusion.
Use of plasma late on cardiopulmonary bypass in patients undergoing left ventricular assist device implantation
Nelson, James A. , Soto, Juan C. Diaz , Stulak, John M., Schulte, Phillip J. , Weister, Timothy J. , Mauermann, William J., Diaz Soto, Juan C, Smith, Mark M , Nelson, James A. , Warner, Matthew A. , Smith, Mark M.

Artificial Organs | August 17, 2021 | Volume: 46 | Issue: 3 | Pages: 491-500

10.1111/aor.14052 Get It

AbstractCoagulopathy is common during left ventricular assist device (LVAD) implantation, treatment of which can be challenging given the often‐limited ability for the right ventricle to accommodate volume transfusion after device initiation with 20% to 40% of patients developing right ventricular failure (RVF). Transfusion of plasma late on cardiopulmonary bypass (CPB) combined with ultrafiltration may replace clotting factors while reducing volume administration. We compared outcomes in patients undergoing LVAD implantation receiving plasma on CPB and ultrafiltration with traditional transfusion practices. Co‐primary outcomes needed for blood product transfusion in the first 6 and 24 hours after CPB. Secondary outcomes included metrics of morbidity and mortality. 396 patients were analyzed (59 plasma on CPB). Patients receiving plasma on CPB had a greater volume of blood products transfused (3764 vs. 2741 mL first 6 hours; 6059 vs. 4305 mL first 24 hours) in unadjusted analysis. In adjusted analysis, plasma transfusion on CPB with ultrafiltration had no significant effect on the primary outcomes of blood products given in the first 6 hours (estimated effect size 982 [−428, 2392] mL, P = .17) and 24 hours (estimated effect size 1076 [−904, 3057] mL, P = .29). Patients receiving plasma on CPB were more likely on either vasopressors or inotropes at 24 hours after ICU admission (P = .01), however, indices of coagulopathy and RVF were similar between groups. While prospective studies would be necessary to definitively evaluate the clinical utility of this strategy, no signal for benefit was observed suggesting plasma should not be used for this purpose.
Plasma, platelet and red blood cell transfusion ratios for life‐threatening non‐traumatic haemorrhage in medical and post‐surgical patients: An observational study
Matzek, Luke J. , Kurian, Emil B., Frank, Ryan D. , Weister, Timothy J. , Kor, Daryl J. , Gajic, Ognjen , Warner, Matthew A.

Vox Sanguinis | August 2, 2021 | Volume: 117 | Issue: 3 | Pages: 361-370

10.1111/vox.13188 Get It

Abstract Background and Objectives Despite the broad utilization of component‐based transfusion strategies that aim to reconstitute whole blood during acute traumatic haemorrhage, data for haemorrhage occurring outside of trauma and surgery are limited. Methods This is an observational cohort study of adults experiencing critical non‐traumatic, non‐intraoperative haemorrhage during hospitalization at an academic medical centre from 2011 to 2015. The primary goal was to evaluate differences in plasma and platelet to red blood cell (RBC) transfusion ratios across patient demographic, clinical and laboratory characteristics. Secondarily, associations between transfusion ratios and clinical outcomes were assessed. Results Seven hundred nine patients were included: 498 (70.2%) medical and 211 (29.8%) post surgical. The gastrointestinal tract (36.7%) was the most common site of bleeding. Most patients received RBCs without plasma (35.5%) or platelets (54.2%). Among those receiving plasma, 82.3% received a plasma to RBC ratio < 1:1 at 24 h. For platelets, the most common ratio was 1–2:1 (52.9%). Transfusion ratios were generally consistent across comorbid disease severity, admission type and anatomic sites of bleeding. Higher plasma utilization was observed in the emergency department, while greater platelet utilization occurred in intensive care units. Higher transfusion ratios were observed in those with greater laboratory haemostatic abnormalities prior to the haemorrhagic event. Clinical outcome differences were limited, though greater platelet utilization in the first 24 h was associated with higher mortality and fewer hospital‐free days. Conclusions Transfusion ratios for critical non‐traumatic haemorrhage were primarily related to laboratory abnormalities preceding the haemorrhagic event and practice environments. Clinical outcome differences across ratios were limited.
Rule-Based Cohort Definitions for Acute Respiratory Distress Syndrome: A Computable Phenotyping Strategy Based on the Berlin Definition
Li, Heyi , Odeyemi, Yewande , Weister, Timothy J. , Liu, Chang , Chalmers, Sarah , Lal, Amos , Song, Xuan , Odeyemi, Yewande E, Chalmers, Sarah J, Lal, Amos , Gajic, Ognjen , Kashyap, Rahul

Critical Care Explorations | June 11, 2021 | Volume: 3 | Issue: 6 | Pages: e0451

10.1097/cce.0000000000000451 Get It

OBJECTIVES: Accurate identification of acute respiratory distress syndrome is essential for understanding its epidemiology, patterns of care, and outcomes. We aimed to design a computable phenotyping strategy to detect acute respiratory distress syndrome in electronic health records of critically ill patients. DESIGN: This is a retrospective cohort study. Using a near real-time copy of the electronic health record, we developed a computable phenotyping strategy to detect acute respiratory distress syndrome based on the Berlin definition. SETTING: Twenty multidisciplinary ICUs in Mayo Clinic Health System. SUBJECTS: The phenotyping strategy was applied to 196,487 consecutive admissions from year 2009 to 2019. INTERVENTIONS: The acute respiratory distress syndrome cohort generated by this novel strategy was compared with the acute respiratory distress syndrome cohort documented by clinicians during the same period. The sensitivity and specificity of the phenotyping strategy were calculated in randomly selected patient cohort (50 patients) using the results from manual medical record review as gold standard. MEASUREMENTS AND MAIN RESULTS: Among the patients who did not have acute respiratory distress syndrome documented, the computable phenotyping strategy identified 3,169 adult patients who met the Berlin definition, 676 patients (21.3%) were classified to have severe acute respiratory distress syndrome (Pao 2/Fio 2 ratio ≤ 100), 1,535 patients (48.4%) had moderate acute respiratory distress syndrome (100 < Pao 2/Fio 2 ratio ≤ 200), and 958 patients (30.2%) had mild acute respiratory distress syndrome (200 < Pao 2/Fio 2 ratio ≤ 300). The phenotyping strategy achieved a sensitivity of 94.4%, specificity of 96.9%, positive predictive value of 94.4%, and negative predictive value of 96.9% in a randomly selected patient cohort. The clinicians documented acute respiratory distress syndrome in 1,257 adult patients during the study period. The clinician documentation rate of acute respiratory distress syndrome was 28.4%. Compared with the clinicians’ documentation, the phenotyping strategy identified a cohort that had higher acuity and complexity of illness suggested by higher Sequential Organ Failure Assessment score (9 vs 7; p < 0.0001), higher Acute Physiology and Chronic Health Evaluation score (76 vs 63; p < 0.0001), higher rate of requiring invasive mechanical ventilation (99.1% vs 71.8%; p < 0.0001), higher ICU mortality (20.6% vs 16.8%; p < 0.0001), and longer ICU length of stay (5.1 vs 4.2 d; p < 0.0001). CONCLUSIONS: Our rule-based computable phenotyping strategy can accurately detect acute respiratory distress syndrome in critically ill patients in the setting of high clinical complexity. This strategy can be applied to enhance early recognition of acute respiratory distress syndrome and to facilitate best-care delivery and clinical research in acute respiratory distress syndrome.
WITHDRAWN: Developing an Electronic Search Strategy Algorithm for Detecting Professional Interpreter Use among Patients with Limited English Proficiency: A Derivation and Validation Study
Soleimani, Jalal , Weister, Timothy J. , Marquez, Alberto, Barwise, Amelia

No container title available | December 21, 2020 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-126974/v1 Get It

Abstract Background Evidence exists that disparities occur for patients with Limited English Proficiency (LEP) that impact the quality of medical services, outcomes, and patient satisfaction. Using interpreter services can reduce these negative impacts; therefore optimizing our understanding of interpreter use during patient care is important. Manual chart review is time-consuming. The objective of this study was to develop and validate a search strategy algorithm to detect patients who used professional interpreter services during their hospitalization. Methods We identified all adults who were admitted to the hospital who had at least one Intensive Care Units (ICU) admission during the hospital stay across the Mayo Clinic Enterprise between January 1, 2015, and June 30, 2020. Three random subsets of 100 patients were extracted from 60,268 patients admitted to an ICU to develop the search strategy algorithm. A physician reviewer conducted the gold standard manual chart review and these results were compared with the search strategy algorithm each time it was refined. Iterative modification of the search strategy was performed and sensitivity and specificity were calculated by comparing the results to the reference standard for both derivation cohorts and the final validation cohort. Any uncertainties were resolved by a second physician researcher. Results The first search strategy resulted in a specificity of 95.7% and a sensitivity of 93.5%. The second revised search strategy achieved a specificity of 96.7% and a sensitivity of 92.3%. The final version of the search strategy was applied to the validation subset and specificity and sensitivity were 92.6% and 100% respectively. Conclusion We successfully derived and validated a search strategy algorithm to assess interpreter use among hospitalized patients. Developing a search strategy algorithm with a high sensitivity can reduce the time required to abstract data from the medical record compared to manual chart review. This can be used to examine and understand patient needs for research and quality improvement initiatives.
Concomitant Aspirin and Anticoagulation Is Associated With Increased Risk for Major Bleeding in Surgical Patients Requiring Postoperative Intensive Care*
Rayes, Hamza, Subat, Yosuf W., Weister, Timothy J. , Johnson, Madeline Q., Hanson, Andrew C. , Schulte, Phillip J. , Trivedi, Vrinda, Gajić, Ognjen, Rayes, Hamza A, Weister, Timothy, Hanson, Andrew, Gajic, Ognjen , Warner, Matthew A.

Critical Care Medicine | April 16, 2020 | Volume: 48 | Issue: 7 | Pages: 985-992

10.1097/ccm.0000000000004350 Get It

Objectives: Critically ill surgical patients may receive concomitant aspirin and therapeutic anticoagulation postoperatively, yet the safety of this practice remains unknown. We evaluated the risk of major bleeding with concomitant therapy compared with anticoagulation alone. Design: Observational cohort study. Inverse probability of treatment weighting was used to assess the association between concomitant therapy and a primary outcome of major bleeding. Setting: Postoperative ICUs at an academic medical center. Patients: Adults (≥ 18 yr old) receiving anticoagulation during postoperative ICU admission between 2007 and 2016. Interventions: None. Measurements and Main Results: Nine thousand five hundred eighteen anticoagulated patients were included, including 3,237 (34%) receiving aspirin. A total of 1,874 unique patients (19.7%) experienced a major bleeding event. In inverse probability of treatment weighting analyses, concomitant therapy was associated with increased odds for major bleeding (odds ratio, 1.20; 95% CI, 1.05–1.36; p = 0.006) compared with anticoagulation alone. An interaction test suggested a differential relationship between aspirin use and major bleeding based on aspirin use in the 7 days prior to anticoagulation, such that a strong association between aspirin and major bleeding was observed for recent initiators of aspirin (1.40; 1.13–1.72;p = 0.002) but not for those continuing prior aspirin use. Aspirin use prior to anticoagulation did not modify the relationship between concomitant therapy and new myocardial infarction or stroke (i.e., rates were not increased with aspirin discontinuation prior to anticoagulation). Conclusions: Concomitant aspirin and anticoagulation in critically ill surgical patients was associated with an increased rate of major bleeding. Future investigations are warranted to further define optimal management of antiplatelet therapy during anticoagulation in surgical patients.