DERIVATION OF A MORTALITY PREDICTION MODEL IN CRITICAL CARE PATIENTS WITH CIRRHOSIS AND SEPSIS.

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.

Comparative costs for critically ill patients with limited English proficiency versus English proficiency.

OBJECTIVES: To conduct comparative cost analysis of hospital care for critically ill patients with Limited English Proficiency (LEP) versus patients with English proficiency (controls). PATIENTS AND METHODS: We conducted a historical cohort study using propensity matching at Mayo Clinic Rochester, a quaternary care academic center. We included hospitalized patients who had at least one admission to ICU during a 10-year period between 1/1/2008-12/31/2017. RESULTS: Due to substantial differences in baseline characteristics of the groups, propensity matching for the covariates age, sex, race, ethnicity, APACHE 3 score, and Charlson Comorbidity score was used, and we achieved the intended balance. The final cohort included 80,404 patients, 4,246 with LEP and 76,158 controls. Patients with LEP had higher costs during hospital admission to discharge, with a mean cost difference of $3861 (95% CI $822 to $6900, p = 0.013) and also higher costs during index ICU admission to hospital discharge, with a mean cost difference of $3166 (95% CI $231 to $6101, p = 0.035). A propensity matched cohort including only those that survived showed those with LEP had significantly greater mean costs for all outcomes. Sensitivity analysis revealed that international patients with LEP had significantly greater overall hospital costs of $9,240 than patients with LEP who resided in the US (95% CI $3341 to $15,140, p = 0.002). CONCLUSION: This is the first study to demonstrate significantly higher costs for patients with LEP experiencing a critical illness. The causes for this may be increased healthcare utilization secondary to communication deficiencies that impede timely decision making about care.

Admission serum sodium and osmolarity are not associated with the occurrence or outcomes of acute respiratory distress syndrome in critically ill.

BACKGROUND: Previous studies suggested that hypernatremia or hyperosmolarity may have protective effects in lung injury. We hypothesized that hypernatremia and/or hyperosmolarity would prevent ARDS. DESIGN: Retrospective cohort study of all admissions at medical, surgical, and multidisciplinary intensive care units in Mayo Clinic, Rochester from the year of 2009 to 2019. 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. RESULTS: Among 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 and osmolarity level did not have a significant association with their outcomes. CONCLUSIONS: Admission serum sodium or serum osmolarity were not associated with the occurrence or outcomes of ARDS in ICU.

Detecting professional interpreter use among patients with limited English proficiency: Derivation and validation study.

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.

Disparities in Hypoxemia Detection by Pulse Oximetry Across Self-Identified Racial Groups and Associations With Clinical Outcomes.

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.

Coagulopathy 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.

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.

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 (Pao2/Fio2 ratio ≤ 100), 1,535 patients (48.4%) had moderate acute respiratory distress syndrome (100 < Pao2/Fio2 ratio ≤ 200), and 958 patients (30.2%) had mild acute respiratory distress syndrome (200 < Pao2/Fio2 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.

Clinical Effect of Systemic Steroids in Patients with Cirrhosis and Septic Shock.

PURPOSE: Evidence regarding the utility of systemic steroids in treating patients with cirrhosis and septic shock remains equivocal. This study aimed to evaluate and elucidate the association of steroid use with outcomes and adverse effects in a cohort of patients with cirrhosis and septic shock. PATIENTS AND METHODS: Retrospective cohort study of patients with cirrhosis and septic shock admitted to a tertiary hospital intensive care unit (ICU) from January 2007 to May 2017, using a validated ICU Datamart. Patients who received vasopressors within 6 h of ICU admission were included in the multivariate analysis. The effect of steroids on outcomes was evaluated using multivariable regression, adjusting for confounding variables. RESULTS: Out of 179 admissions of patients with cirrhosis and septic shock, 56 received steroids during the ICU admission. Patients who received steroids received a higher total dose of vasopressors (91.2 mg vs. 39.1 mg, P = 0.04) and had a lower initial lactate level (1.8 mmol/L vs. 2.6 mmol/L, P = 0.007). The multivariate analysis included 117 patients and showed no significant differences in mortality, length of ICU admission, or length of hospital stay. Bleeding events, delirium, and renal-replacement therapy requirements were also not associated with the use of steroids. CONCLUSION: The use of systemic steroids was more prevalent in cirrhotic patients with higher vasopressor requirements. It was not associated with decreased mortality or increased ICU- and hospital-free days, or to adverse effects.

Derivation and Validation of an Automated Search Strategy to Retrospectively Identify Acute Respiratory Distress Patients Per Berlin Definition.

Purpose: Acute respiratory distress syndrome (ARDS) is common in critically ill patients and linked with serious consequences. A manual chart review for ARDS diagnosis could be laborious and time-consuming. We developed an automated search strategy to retrospectively identify ARDS patients using the Berlin definition to allow for timely and accurate ARDS detection. Methods: The automated search strategy was created through sequential steps, with keywords applied to an institutional electronic medical records (EMRs) database. We included all adult patients admitted to the intensive care unit (ICU) at the Mayo Clinic (Rochester, MN) from January 1, 2009 to December 31, 2017. We selected 100 patients at random to be divided into two derivation cohorts and identified 50 patients at random for the validation cohort. The sensitivity and specificity of the automated search strategy were compared with a manual medical record review (gold standard) for data extraction of ARDS patients per Berlin definition. Results: On the first derivation cohort, the automated search strategy achieved a sensitivity of 91.3%, specificity of 100%, positive predictive value (PPV) of 100%, and negative predictive value (NPV) of 93.1%. On the second derivation cohort, it reached the sensitivity of 90.9%, specificity of 100%, PPV of 100%, and NPV of 93.3%. The strategy performance in the validation cohort had a sensitivity of 94.4%, specificity of 96.9%, PPV of 94.4%, and NPV of 96.9%. Conclusions: This automated search strategy for ARDS with the Berlin definition is reliable and accurate, and can serve as an efficient alternative to time-consuming manual data review.

An Electronic Search Algorithm for Early Disseminated Intravascular Coagulopathy Diagnosis in the Intensive Care Unit: A Derivation and Validation Study.

AIM: We aim to create and validate an electronic search algorithm for accurate detection of disseminated intravascular coagulopathy (DIC) from medical records. METHODS: Patients with DIC in Mayo Clinic's intensive care units (ICUs) from Jan 1, 2007, to May 4, 2018, were included in the study. An algorithm was developed based on clinical notes and ICD diagnosis codes. A cohort of 50 patients was included with DIC diagnosis, its variations, and no diagnosis of DIC. Then, the next set of 50 patients was used to refine the algorithm. Results were compared with a manual reviewer and the disagreements were resolved by the third reviewer. The same process was repeated with 'revised clinical note search' for the first and second derivation cohort with additional exclusion terms. The obtained sensitivity and specificity were reported. The generated algorithm was applied to another set of 50 patients for validation. RESULTS: In the first derivation cohort- DIC search by clinical notes and diagnosis codes had 92% sensitivity and 100% specificity. Sensitivity dropped to 71% in the second cohort although specificity remains the same. Therefore, the algorithm was refined to clinical notes search only. The revised search was reapplied to first and second derivation cohorts and results obtained for the first derivation were the same but 91.3% sensitive and 100% specific for the second derivation. The search was locked and applied in the validation cohort with 95.8% sensitivity and 100% specificity, respectively. CONCLUSION: The revised clinical note based electronic search algorithm was found to be highly sensitive and specific for DIC during the corresponding ICU duration.

Timing of resumption of beta-blockers after discontinuation of vasopressors is not associated with post-operative atrial fibrillation in critically ill patients recovering from non-cardiac surgery: A retrospective cohort analysis.

BACKGROUND: Post-operative atrial fibrillation is a complication with high morbidity. In patients on prior-to-admission beta-blockers, early post-operative beta-blockade reduces atrial fibrillation risk; however, this benefit is not studied in hemodynamically unstable patients requiring vasopressors. METHODS: A retrospective analysis was performed at two high-volume centers of adult patients on home beta-blockers, undergoing non-cardiac surgery between 2005 and 2015, and who required post-operative vasopressors. Patients were divided into early beta-blockers (within 24 h) or delayed from vasopressor cessation. The primary outcome was the atrial fibrillation incidence. A propensity score was developed for early beta-blockers and used for adjustment. RESULTS: Eight-hundred seventy one patients required post-operative vasopressors; 423 in the early group and 448 in the delayed group. In the delayed beta-blocker group, intraoperative hypotension was more common (21.6% versus 24.1%, p < 0.001), APACHE III scores higher (56.6 versus 50.8, p < 0.001) and more post-operative norephinephrine use (56.7% veruss 30.3%, p < 0.001). Eighty eight patients developed atrial fibrillation: 40 in the early group, and 48 in the delayed group (p = 0.538). After adjustment, early beta-blockade was not associated with changed incidence of atrial fibrillation. CONCLUSIONS: In patients requiring postoperative vasopressors, early beta-blockade did not protect against postoperative atrial fibrillation.

Risk of major bleeding associated with aspirin use in non-surgical critically ill patients receiving therapeutic anticoagulation.

BACKGROUND: We aimed to evaluate the risk of major bleeding in non-surgical critically ill patients who received aspirin in conjunction with therapeutic anticoagulation (concomitant therapy) compared to those who received therapeutic anticoagulation alone. METHODS: This is a retrospective cohort study of critically ill patients initiated on therapeutic anticoagulation at a large academic medical center from 2007 to 2016. The exposure of interest was aspirin therapy during anticoagulation. The primary outcome was the incidence of major bleeding during hospitalization. Secondary outcomes included in-hospital mortality, hospital free days, and new myocardial infarction or stroke. RESULTS: 5507 (73.2%) patients received anticoagulation alone and 2014 (26.8%) received concomitant therapy; major bleeding occurred in 19.0% and 22.2%, respectively. There was no increased risk of major bleeding [OR 1.10 (95% CI: 0.93-1.30); p = .27] or mortality [OR 0.93 (95% CI: 0.77-1.11); p = .43] with concomitant therapy. Patients receiving concomitant therapy had fewer hospital-free days (mean decrease of 0.73 [1.36, 0.09]; p = .03) and were more likely to experience new myocardial infarction or stroke [OR 2.61 (95% CI: 1.72-3.98); p < .001]. CONCLUSIONS: In non-surgical critically ill patients receiving therapeutic anticoagulation, concomitant use of aspirin was not associated with an increased risk of bleeding or in-hospital mortality.

Concomitant Aspirin and Anticoagulation Is Associated With Increased Risk for Major Bleeding in Surgical Patients Requiring Postoperative Intensive Care.

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.

Acute pulmonary embolism in patients with obstructive sleep apnea: frequency, hospital outcomes, and recurrence.

STUDY OBJECTIVES: The objectives of this study were to assess the effect of obstructive sleep apnea (OSA) on the risk of acute pulmonary embolism (PE), hospital outcomes including mortality, and PE recurrence. METHODS: We retrospectively enrolled adult patients, admitted to Mayo Clinic Hospital in Rochester, Minnesota, within a 5-year period (2009-2013). We compared frequency of PE, hospital mortality, and secondary outcomes in patients with OSA versus patients without OSA. We assessed risk of PE recurrence in relation to compliance with OSA therapy. RESULTS: Of 25,038 patients, 3,184 (13%) had OSA and 283 (1.1%) experienced PE. Frequency of PE in patients with and without OSA was 2.4% versus 0.9% (odds ratio [OR], 2.51; 95% confidence interval [CI], 1.9-3.3; P < .001). OSA was independently associated with increased risk of PE after adjusting for demographics and comorbidities (OR, 1.44; 95% CI, 1.07-1.9; P = .017). Adjusted hospital mortality was increased in patients with PE (OR, 2.88; 95% CI, 1.7-4.9; P < .001) but not in patients with OSA (OR, 0.98; 95% CI, 0.7-1.4, P = .92). OSA was not a significant determining factor for mortality in patients who experienced a PE (OR, 0.56; 95% CI, 0.1.1-2.78; P = .47), adjusting for demographics, PE severity, and Charlson comorbidity index. Adjusted risk of PE recurrence was greater in patients with OSA compared with patients without OSA (OR, 2.21; 95% CI, 1.05-4.68; P < .04). The patients compliant with OSA therapy had a lower rate of PE recurrence (16% vs 32%; P = not significant). CONCLUSIONS: Although OSA significantly increases risk of acute PE occurrence and recurrences, related hospital mortality was not greater in patients with OSA compared with those without OSA. OSA therapy might have a modifying effect on PE recurrence.

Intraoperative Plasma Transfusion Volumes and Outcomes in Cardiac Surgery.

OBJECTIVE: Assess outcomes after intraoperative plasma transfusion in patients undergoing cardiac surgery. DESIGN: Retrospective study of adult cardiac surgical between 2011 and 2015. Relationships between plasma transfusion volume, coagulation test values, and a primary outcome of early postoperative red blood cell (RBC) transfusion were assessed via multivariable regression analyses. Secondary outcomes included hospital mortality, intensive care unit and hospital-free days, intraoperative RBCs, estimated blood loss, and reoperation for bleeding. SETTING: Academic tertiary referral center. PARTICIPANTS: A total of 1,794 patients received intraoperative plasma transfusions during the study period. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Higher plasma transfusion volumes were associated with worse clinical outcomes, with each 1-unit increase being associated with greater odds for postoperative RBCs [odds ratio (OR) 1.12 (confidence interval [CI] 1.04-1.20); p = 0.002], intraoperative [OR 1.85 (CI 1.69-2.03); p < 0.001], and fewer hospital-free days [mean -0.20 (-0.39, -0.01); p = 0.04]. Each 0.1 increase in pretransfusion International Normalized Ratio (INR) was associated with increased odds of postoperative and intraoperative RBCs, reoperation for bleeding, and fewer intensive care unit and hospital-free days. For given plasma volumes, patients achieving greater reduction in elevated pretransfusion INR values experienced more favorable outcomes. CONCLUSIONS: In patients undergoing cardiac surgery who received intraoperative plasma transfusion, higher plasma transfusion volumes were associated with inferior clinical outcomes. Higher pretransfusion INR values also were associated with worse outcomes; however, those achieving a greater degree of INR correction after plasma transfusion demonstrated more favorable outcomes. Prospective studies related to plasma transfusion are needed to address this important topic.

Ratios of Plasma and Platelets to Red Blood Cells in Surgical Patients With Acute Intraoperative Hemorrhage.

BACKGROUND: The relationships between the ratios of transfused allogeneic blood products and clinical outcomes in patients with acute intraoperative hemorrhage are poorly defined. METHODS: To better define these ratios, we undertook a single-center, observational cohort study of all surgical patients (≥18 years) who received rapid transfusion defined by a critical administration threshold of 3 or more units of red blood cells (RBCs) intraoperatively within 1 hour between January 1, 2011 and December 31, 2015. Multivariable regression analyses were used to assess relationships between ratios of plasma to RBCs and platelets to RBCs at 3, 12, and 24 hours and clinical outcomes. The primary outcome was hospital mortality, with secondary outcomes of intensive care unit and hospital-free days. RESULTS: The study included 2385 patients, of whom 14.9% had a plasma-to-RBC ratio of 1.0+, and 47.6% had a platelet-to-RBC ratio of 1.0+. Higher plasma-to-RBC and platelet-to-RBC ratios were observed for patients who underwent cardiac, transplant, and vascular surgery and in patients with greater derangements in hemostatic laboratory values. Ratios did not differ by patient age or severity of illness. Higher ratios were not associated with improved clinical outcomes. Mortality differed by platelet-to-RBC but not plasma-to-RBC ratio, with the highest mortality observed with a platelet-to-RBC ratio of 0.1-0.9 at 24 hours (odds ratio, 3.34 [1.62-6.88]) versus no platelets (P= .001). Higher plasma-to-RBC ratios were associated with decreased hospital-free days, although differences in clinical outcomes were not significant after exclusion of patients receiving only RBCs without component therapies. CONCLUSIONS: Transfusion ratios in surgical patients with critical intraoperative hemorrhage were largely related to surgical and hemostatic features rather than baseline patient characteristics. Higher ratios were not associated with improved outcomes.

Machine learning in data abstraction: A computable phenotype for sepsis and septic shock diagnosis in the intensive care unit.

BACKGROUND: With the recent change in the definition (Sepsis-3 Definition) of sepsis and septic shock, an electronic search algorithm was required to identify the cases for data automation. This supervised machine learning method would help screen a large amount of electronic medical records (EMR) for efficient research purposes. AIM: To develop and validate a computable phenotype via supervised machine learning method for retrospectively identifying sepsis and septic shock in critical care patients. METHODS: A supervised machine learning method was developed based on culture orders, Sequential Organ Failure Assessment (SOFA) scores, serum lactate levels and vasopressor use in the intensive care units (ICUs). The computable phenotype was derived from a retrospective analysis of a random cohort of 100 patients admitted to the medical ICU. This was then validated in an independent cohort of 100 patients. We compared the results from computable phenotype to a gold standard by manual review of EMR by 2 blinded reviewers. Disagreement was resolved by a critical care clinician. A SOFA score ≥ 2 during the ICU stay with a culture 72 h before or after the time of admission was identified. Sepsis versions as V1 was defined as blood cultures with SOFA ≥ 2 and Sepsis V2 was defined as any culture with SOFA score ≥ 2. A serum lactate level ≥ 2 mmol/L from 24 h before admission till their stay in the ICU and vasopressor use with Sepsis-1 and-2 were identified as Septic Shock-V1 and-V2 respectively. RESULTS: In the derivation subset of 100 random patients, the final machine learning strategy achieved a sensitivity-specificity of 100% and 84% for Sepsis-1, 100% and 95% for Sepsis-2, 78% and 80% for Septic Shock-1, and 80% and 90% for Septic Shock-2. An overall percent of agreement between two blinded reviewers had a k = 0.86 and 0.90 for Sepsis 2 and Septic shock 2 respectively. In validation of the algorithm through a separate 100 random patient subset, the reported sensitivity and specificity for all 4 diagnoses were 100%-100% each. CONCLUSION: Supervised machine learning for identification of sepsis and septic shock is reliable and an efficient alternative to manual chart review.

Initial Postoperative Hemoglobin Values and Clinical Outcomes in Transfused Patients Undergoing Noncardiac Surgery.

BACKGROUND: Intraoperative red blood cell (RBC) transfusion is common, yet transfusion strategies remain controversial as pretransfusion hemoglobin triggers are difficult to utilize during acute bleeding. Alternatively, postoperative hemoglobin values may provide useful information regarding transfusion practices, though optimal targets remain undefined. METHODS: This is a single-center observational cohort study of adults receiving allogeneic RBCs during noncardiac surgery from 2010 through 2014. Multivariable regression analyses adjusting for patient illness, laboratory derangements, and surgical features were used to assess relationships between initial postoperative hemoglobin values and a primary outcome of hospital-free days. RESULTS: A total of 8060 patients were included. Those with initial postoperative hemoglobin <7.5 or ≥11.5 g/dL had decreased hospital-free days [mean (95% confidence interval [CI]), -1.45 (-2.50 to -0.41) and -0.83 (-1.42 to -0.24), respectively] compared to a reference range of 9.5-10.4 g/dL (overall P value .003). For those with hemoglobin <7.5 g/dL, the odds (95% CI) for secondary outcomes included acute kidney injury (AKI) 1.43 (1.03-1.99), mortality 2.10 (1.18-3.74), and cerebral ischemia 3.12 (1.08-9.01). The odds for postoperative mechanical ventilation with hemoglobin ≥11.5 g/dL were 1.33 (1.07-1.65). Secondary outcome associations were not significant after multiple comparisons adjustment (Bonferroni P < .0056). CONCLUSIONS: In transfused patients, postoperative hemoglobin values between 7.5 and 11.5 g/dL were associated with superior outcomes compared to more extreme values. This range may represent a target for intraoperative transfusions, particularly during active bleeding when pretransfusion hemoglobin thresholds may be impractical or inaccurate. Given similar outcomes within this range, targeting hemoglobin at the lower aspect may be preferable, though prospective validation is warranted.

Higher intraoperative plasma transfusion volumes are associated with inferior perioperative outcomes.

BACKGROUND: Intraoperative plasma transfusion is common, yet little is known regarding its effects on perioperative coagulation tests or clinical outcomes. STUDY DESIGN AND METHODS: This is a retrospective cohort study of adults receiving intraoperative plasma transfusion at a single center from 2011 to 2015. Relationships between plasma transfusion volume, changes in coagulation test values, and clinical outcomes, including a primary outcome of early postoperative red blood cell (RBC) transfusion, were assessed with multivariable regression analyses. Secondary outcomes included hospital mortality, intensive care unit (ICU)- and hospital-free days, intraoperative RBC transfusions, and estimated blood loss. RESULTS: A total of 3393 unique patients were included, with median (IQR) transfusion of 2 (2-4) units. In multivariable analyses, higher plasma volumes were associated with worse outcomes, with each 1 mL/kg increase associated with increased odds for postoperative (1.02 [1.01-1.03], p < 0.001) and intraoperative RBCs (1.17 [1.16-1.19], p < 0.001) and fewer ICU- and hospital-free days (mean difference [95% CI], -0.08 [-0.12 to -0.05], p < 0.001; and -0.09 [-0.13 to -0.06], p < 0.001, respectively). Greater decreases in international normalized ratio (INR) following plasma transfusion were associated with decreased odds of postoperative RBCs (0.35 [0.25-0.47], p < 0.001), decreased mortality (0.50 [0.31-0.83], p = 0.007), and increased mean ICU- (1.31 [0.41-2.21], p = 0.004) and hospital-free days (1.15 [0.19-2.10], p = 0.018). CONCLUSION: In patients receiving intraoperative plasma transfusion, higher transfusion volumes were associated with inferior clinical outcomes; however, greater improvements in INR were associated with improved outcomes. Future prospective studies are necessary to better define these relationships and to explore plasma transfusion triggers beyond the limitations of INR.