Clinical decision support to reduce unnecessary diagnostic testing for heparin-induced thrombocytopenia.

Appropriate evaluation of heparin-induced thrombocytopenia (HIT) is imperative because of the potentially life-threatening complications. However, overtesting and overdiagnosis of HIT are common. Our goal was to evaluate the impact of clinical decision support (CDS) based on the HIT computerized-risk (HIT-CR) score, designed to reduce unnecessary diagnostic testing. This retrospective observational study evaluated CDS that presented a platelet count versus time graph and 4Ts score calculator to clinicians who initiated a HIT immunoassay order in patients with predicted low risk (HIT-CR score 0-2). The primary outcome was the proportion of immunoassay orders initiated but cancelled after firing of the CDS advisory. Chart reviews were conducted to assess anticoagulation usage, 4Ts scores and the proportion of patients who had HIT. In a 20-week period, 319 CDS advisories were presented to users who initiated potentially unnecessary HIT diagnostic testing. The diagnostic test order was discontinued in 80 (25%) patients. Heparin products were continued in 139 (44%) patients, and alternative anticoagulation was not given to 264 (83%). The negative predictive value of the advisory was 98.8% (95% CI: 97.2-99.5). HIT-CR score-based CDS can reduce unnecessary diagnostic testing for HIT in patients with a low pretest probability of HIT.

COVID-19 Time of Intubation Mortality Evaluation (C-TIME): A system for predicting mortality of patients with COVID-19 pneumonia at the time they require mechanical ventilation.

BACKGROUND: An accurate system to predict mortality in patients requiring intubation for COVID-19 could help to inform consent, frame family expectations and assist end-of-life decisions. RESEARCH OBJECTIVE: To develop and validate a mortality prediction system called C-TIME (COVID-19 Time of Intubation Mortality Evaluation) using variables available before intubation, determine its discriminant accuracy, and compare it to acute physiology and chronic health evaluation (APACHE IVa) and sequential organ failure assessment (SOFA). METHODS: A retrospective cohort was set in 18 medical-surgical ICUs, enrolling consecutive adults, positive by SARS-CoV 2 RNA by reverse transcriptase polymerase chain reaction or positive rapid antigen test, and undergoing endotracheal intubation. All were followed until hospital discharge or death. The combined outcome was hospital mortality or terminal extubation with hospice discharge. Twenty-five clinical and laboratory variables available 48 hours prior to intubation were entered into multiple logistic regression (MLR) and the resulting model was used to predict mortality of validation cohort patients. Area under the receiver operating curve (AUROC) was calculated for C-TIME, APACHE IVa and SOFA. RESULTS: The median age of the 2,440 study patients was 66 years; 61.6 percent were men, and 50.5 percent were Hispanic, Native American or African American. Age, gender, COPD, minimum mean arterial pressure, Glasgow Coma scale score, and PaO2/FiO2 ratio, maximum creatinine and bilirubin, receiving factor Xa inhibitors, days receiving non-invasive respiratory support and days receiving corticosteroids prior to intubation were significantly associated with the outcome variable. The validation cohort comprised 1,179 patients. C-TIME had the highest AUROC of 0.75 (95%CI 0.72-0.79), vs 0.67 (0.64-0.71) and 0.59 (0.55-0.62) for APACHE and SOFA, respectively (Chi2 P<0.0001). CONCLUSIONS: C-TIME is the only mortality prediction score specifically developed and validated for COVID-19 patients who require mechanical ventilation. It has acceptable discriminant accuracy and goodness-of-fit to assist decision-making just prior to intubation. The C-TIME mortality prediction calculator can be freely accessed on-line at https://phoenixmed.arizona.edu/ctime.

The relationship of tidal volume and driving pressure with mortality in hypoxic patients receiving mechanical ventilation.

PURPOSE: To determine whether tidal volume/predicted body weight (TV/PBW) or driving pressure (DP) are associated with mortality in a heterogeneous population of hypoxic mechanically ventilated patients. METHODS: A retrospective cohort study involving 18 intensive care units included consecutive patients ≥18 years old, receiving mechanical ventilation for ≥3 days, with a PaO2/FiO2 ratio ≤300 mmHg, whether or not they met full criteria for ARDS. The main outcome was hospital mortality. Multiple logistic regression (MLR) incorporated TV/PBW, DP, and potential confounders including age, APACHE IVa® predicted hospital mortality, respiratory system compliance (CRS), and PaO2/FiO2. Predetermined strata of TV/PBW were compared using MLR. RESULTS: Our cohort comprised 5,167 patients with mean age 61.9 years, APACHE IVa® score 79.3, PaO2/FiO2 166 mmHg and CRS 40.5 ml/cm H2O. Regression analysis revealed that patients receiving DP one standard deviation above the mean or higher (≥19 cmH20) had an adjusted odds ratio for mortality (ORmort) = 1.10 (95% CI: 1.06-1.13, p = 0.009). Regression analysis showed a U-shaped relationship between strata of TV/PBW and adjusted mortality. Using TV/PBW 4-6 ml/kg as the referent group, patients receiving >10 ml/kg had similar adjusted ORmort, but those receiving 6-7, 7-8 and 8-10 ml/kg had lower adjusted ORmort (95%CI) of 0.81 (0.65-1.00), 0.78 (0.63-0.97) and 0.80 0.67-1.01) respectively. The adjusted ORmort in patients receiving 4-6 ml/kg was 1.26 (95%CI: 1.04-1.52) compared to patients receiving 6-10 ml/kg. CONCLUSIONS: Driving pressures ≥19 cmH2O were associated with increased adjusted mortality. TV/PBW 4-6ml/kg were used in less than 15% of patients and associated with increased adjusted mortality compared to TV/PBW 6-10 ml/kg used in 82% of patients. Prospective clinical trials are needed to prove whether limiting DP or the use of TV/PBW 6-10 ml/kg versus 4-6 ml/kg benefits mortality.

Computerised risk scores to guide recognition and diagnosis in patients with possible heparin-induced thrombocytopenia.

The heparin-induced thrombocytopenia computerised risk (HIT-CR) score is designed to aid in the diagnosis of HIT. We sought to evaluate its potential clinical utility. In this retrospective cohort study, we collected HIT-CR scores on all inpatients receiving heparin over a 4-month period and performed chart reviews on the subset who independently underwent clinical diagnostic testing for HIT to identify patients with HIT. In all, 34 342 patients received heparin, 1744 had high-risk HIT-CR scores of ≥3 and 220 had the maximal risk score of 4. Only 6% of high-risk and 10% of maximal-risk patients underwent testing for HIT. Conversely, among all 317 patients who underwent independent testing for HIT, 67% had low-risk HIT-CR scores (<3). Among patients independently tested, the positive predictive value (PPV) was 6·6% [95% confidence interval (CI) 4·9-8·8%] and the negative predictive value (NPV) was 99·5% (95% CI 97·1-99·9%) at a HIT-CR score cut-off of 3, and the PPV was 22·7% (95% CI 12·7-37·4%) and NPV was 99·0% (95% CI 97·6-99·6%) at a cut-off of 4. This study suggests clinicians fail to test most high-risk patients and unnecessarily test many low-risk patients for HIT. A reasonable approach to clinical application of HIT-CR scores would be recommending no testing for patients with a score of <3 and recommend testing for patients with a score of 4.

Hospitals with more-active participation in conducting standardized in-situ mock codes have improved survival after in-hospital cardiopulmonary arrest.

AIM: The American Heart Association (AHA) and the Institute of Medicine have published a national "call-to-action" to improve survival from in-hospital cardiopulmonary arrest (IHCA). Our aim was to determine if more-active hospital participation in standardized in-situ mock code (ISMC) training is associated with increased IHCA survival. METHODS: We performed an ecological study across a multi-state healthcare system comprising 26 hospitals. Hospital-level ISMC performance was measured during 2016-2017 and IHCA hospital discharge survival rates in 2017. We performed univariate and multivariate analysis of the hospital-level association between more-active ISCM participation and IHCA survival, with adjustment for hospital expected mortality as determined by a commercial severity scoring system. Other potential confounders were analyzed using univariate statistics. RESULTS: Hospitals with more-active ISMC participation conducted a median of 17.6 ISMCs/100 beds/year (vs 3.2/100 beds/year in less-active hospitals, p = 0.001) in 2016-2017. 220,379 patients were admitted and 3289 experienced IHCA in study hospitals in 2017, with an overall survival rate of 37.4%. Hospitals with more-active ISMC participation had a mean IHCA survival rate of 42.8% vs. 31.8% in hospitals with less-active ISMC participation (p < 0.0001), and a significantly reduced odds ratio (OR) of 0.62 for IHCA mortality (95% CI: 0.54-0.72; p < 0.0001) which was unchanged after adjustment for hospital-level expected mortality (adjusted OR: 0.62; 95% CI: 0.54-0.71; p < 0.001). CONCLUSIONS: Hospitals in our healthcare system with more-active ISMC participation have higher IHCA survival. Prospective trials are needed to establish the efficacy of standardized ISMC training programs in improving patient survival after cardiac arrest.

Extracorporeal membrane oxygenation in acute respiratory distress syndrome due to influenza A (H1N1)pdm09 pneumonia. A single-center experience during the 2013-2014 season. / Oxigenação por membrana extracorpórea na síndrome do desconforto respiratório agudo devido à pneumonia por influenza A (H1N1) pdm09. Experiência em um único centro durante a temporada de 2013-2014.

OBJECTIVE: This report aimed to describe the outcomes of the patients with severe H1N1 associated acute respiratory distress syndrome who were treated with extracorporeal membrane oxygenation therapy. METHODS: This retrospective review analyzed a single-center cohort of adult patients with H1N1-related acute respiratory distress syndrome who were managed with veno-venous extracorporeal membrane oxygenation during the winter of 2013/2014. RESULTS: A total of 10 patients received veno-venous extracorporeal membrane oxygenation for H1N1 influenza between January 2013 and March 2014. Seven patients were transferred to our center for extracorporeal membrane oxygenation consideration (all within 72 hours of initiating mechanical ventilation). The median patient age was forty years, and 30% were female. The median arterial oxygen partial pressure to fraction of inspired oxygen ratio was 62.5, and the median RESP score was 6. Three patients received inhaled nitric oxide, and four patients were proned as rescue therapy before extracorporeal membrane oxygenation was initiated. The median duration of mechanical ventilation was twenty-two days (range, 14 - 32). The median length of stay in the intensive care unit was twenty-seven days (range, 14 - 39). The median hospital length of stay was 29.1 days (range, 16.0 - 46.9). Minor bleeding complications occurred in 6 of 10 patients. Eight of the ten patients survived to hospital discharge. CONCLUSION: The survivors were relatively young and discharged with good functional status (i.e., enhancing quality-adjusted life-years-saved). Our experience shows that even a relatively new extracorporeal membrane oxygenation program can play an important role in that capacity and provide excellent outcomes for the sickest patients.

OBJETIVO: Descrever os desfechos de pacientes com síndrome do desconforto respiratório agudo associada à influenza subtipo H1N1 grave tratados com oxigenação por membrana extracorpórea. MÉTODOS: Trata-se de revisão retrospectiva de uma coorte de pacientes oriunda de um único centro, constituída por adultos com síndrome do desconforto respiratório agudo relacionada com influenza subtipo H1N1 e tratados com oxigenação venovenosa por membrana extracorpórea durante a temporada de inverno no hemisfério norte de 2013/2014. RESULTADOS: Dez pacientes receberam oxigenação venovenosa por membrana extracorpórea para tratamento de influenza subtipo H1N1 entre janeiro de 2013 e março de 2014. Sete deles foram transferidos para nosso centro visando à utilização de oxigenação por membrana extracorpórea dentro de um período de 72 horas após o início da ventilação mecânica. A idade mediana foi de 40 anos, sendo 30% dos pacientes do sexo feminino. O valor mediano da proporção entre pressão parcial de oxigênio e fração inspirada de oxigênio foi de 62,5, sendo o escore RESP mediano de 6. Três pacientes receberam inalação de óxido nítrico e quatro utilizaram posição prona como tratamento de resgate antes de ser iniciada a oxigenação por membrana extracorpórea. A duração mediana da ventilação mecânica foi de 22 dias (variação de 14 - 32). O tempo mediano de permanência na unidade de terapia intensiva foi de 27 dias (variação de 14 - 39). O tempo mediano de permanência no hospital foi de 29,1 dias (variação de 16,0 - 46,9). Ocorreram complicações não importantes de sangramento em seis dos dez pacientes. Oito dos dez pacientes sobreviveram até a alta hospitalar. CONCLUSÃO: Os sobreviventes eram relativamente jovens e tiveram alta com boas condições funcionais, o que salienta os anos de vida ajustados pela qualidade que foram salvos. Nossa experiência demonstra que mesmo um programa ainda relativamente novo de oxigenação por membrana extracorpórea pode desempenhar um papel importante, e proporcionar resultados excelentes para os pacientes mais graves.

Oxigenação por membrana extracorpórea na síndrome do desconforto respiratório agudo devido à pneumonia por influenza A (H1N1) pdm09. Experiência em um único centro durante a temporada de 2013-2014 / Extracorporeal membrane oxygenation in acute respiratory distress syndrome due to influenza A (H1N1)pdm09 pneumonia. A single-center experience during the 2013-2014 season

RESUMO Objetivo: Descrever os desfechos de pacientes com síndrome do desconforto respiratório agudo associada à influenza subtipo H1N1 grave tratados com oxigenação por membrana extracorpórea. Métodos: Trata-se de revisão retrospectiva de uma coorte de pacientes oriunda de um único centro, constituída por adultos com síndrome do desconforto respiratório agudo relacionada com influenza subtipo H1N1 e tratados com oxigenação venovenosa por membrana extracorpórea durante a temporada de inverno no hemisfério norte de 2013/2014. Resultados: Dez pacientes receberam oxigenação venovenosa por membrana extracorpórea para tratamento de influenza subtipo H1N1 entre janeiro de 2013 e março de 2014. Sete deles foram transferidos para nosso centro visando à utilização de oxigenação por membrana extracorpórea dentro de um período de 72 horas após o início da ventilação mecânica. A idade mediana foi de 40 anos, sendo 30% dos pacientes do sexo feminino. O valor mediano da proporção entre pressão parcial de oxigênio e fração inspirada de oxigênio foi de 62,5, sendo o escore RESP mediano de 6. Três pacientes receberam inalação de óxido nítrico e quatro utilizaram posição prona como tratamento de resgate antes de ser iniciada a oxigenação por membrana extracorpórea. A duração mediana da ventilação mecânica foi de 22 dias (variação de 14 - 32). O tempo mediano de permanência na unidade de terapia intensiva foi de 27 dias (variação de 14 - 39). O tempo mediano de permanência no hospital foi de 29,1 dias (variação de 16,0 - 46,9). Ocorreram complicações não importantes de sangramento em seis dos dez pacientes. Oito dos dez pacientes sobreviveram até a alta hospitalar. Conclusão: Os sobreviventes eram relativamente jovens e tiveram alta com boas condições funcionais, o que salienta os anos de vida ajustados pela qualidade que foram salvos. Nossa experiência demonstra que mesmo um programa ainda relativamente novo de oxigenação por membrana extracorpórea pode desempenhar um papel importante, e proporcionar resultados excelentes para os pacientes mais graves.

ABSTRACT Objective: This report aimed to describe the outcomes of the patients with severe H1N1 associated acute respiratory distress syndrome who were treated with extracorporeal membrane oxygenation therapy. Methods: This retrospective review analyzed a single-center cohort of adult patients with H1N1-related acute respiratory distress syndrome who were managed with veno-venous extracorporeal membrane oxygenation during the winter of 2013/2014. Results: A total of 10 patients received veno-venous extracorporeal membrane oxygenation for H1N1 influenza between January 2013 and March 2014. Seven patients were transferred to our center for extracorporeal membrane oxygenation consideration (all within 72 hours of initiating mechanical ventilation). The median patient age was forty years, and 30% were female. The median arterial oxygen partial pressure to fraction of inspired oxygen ratio was 62.5, and the median RESP score was 6. Three patients received inhaled nitric oxide, and four patients were proned as rescue therapy before extracorporeal membrane oxygenation was initiated. The median duration of mechanical ventilation was twenty-two days (range, 14 - 32). The median length of stay in the intensive care unit was twenty-seven days (range, 14 - 39). The median hospital length of stay was 29.1 days (range, 16.0 - 46.9). Minor bleeding complications occurred in 6 of 10 patients. Eight of the ten patients survived to hospital discharge. Conclusion: The survivors were relatively young and discharged with good functional status (i.e., enhancing quality-adjusted life-years-saved). Our experience shows that even a relatively new extracorporeal membrane oxygenation program can play an important role in that capacity and provide excellent outcomes for the sickest patients.

A quality improvement project to improve the Medicare and Medicaid Services (CMS) sepsis bundle compliance rate in a large healthcare system.

Sepsis is a leading cause of mortality and morbidity in hospitalised patients. The Centers for Medicare and Medicaid Services (CMS) mandated that US hospitals report sepsis bundle compliance rate as a quality process measure in October 2015. The specific aim of our study was to improve the CMS sepsis bundle compliance rate from 30% to 40% across 20 acute care hospitals in our healthcare system within 1 year. The study included all adult inpatients with sepsis sampled according to CMS specifications from October 2015 to September 2016. The CMS sepsis bundle compliance rate was tracked monthly using statistical process control charting. A baseline rate of 28.5% with 99% control limits was established. We implemented multiple interventions including computerised decision support systems (CDSSs) to increase compliance with the most commonly missing bundle elements. Compliance reached 42% (99% statistical process control limits 18.4%-38.6%) as CDSS was implemented system-wide, but this improvement was not sustained after CMS changed specifications of the outcome measure. Difficulties encountered elucidate shortcomings of our study methodology and of the CMS sepsis bundle compliance rate as a quality process measure.

Two Cases of Refractory Cardiogenic Shock Secondary to Bupropion Successfully Treated with Veno-Arterial Extracorporeal Membrane Oxygenation.

Bupropion inhibits the uptake of dopamine and norepinephrine. Clinical effects in overdose include seizure, status epilepticus, tachycardia, arrhythmias, and cardiogenic shock. We report two cases of severe bupropion toxicity resulting in refractory cardiogenic shock, cardiac arrest, and repeated seizures treated successfully. Patients with cardiovascular failure related to poisoning may particularly benefit from extracorporeal membrane oxygenation (ECMO). These are the first cases of bupropion toxicity treated with veno-arterial EMCO (VA-ECMO) in which bupropion toxicity is supported by confirmatory testing. Both cases demonstrate the effectiveness of VA-ECMO in poisoned patients with severe cardiogenic shock or cardiopulmonary failure.

Improving clinical interpretation of the anti-platelet factor 4/heparin enzyme-linked immunosorbent assay for the diagnosis of heparin-induced thrombocytopenia through the use of receiver operating characteristic analysis, stratum-specific likelihood ratios, and Bayes theorem.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is diagnosed using clinical criteria and detection of platelet-activating anti-platelet factor 4/heparin (anti-PF4/H) antibodies, usually through a surrogate enzyme-linked immunosorbent assay (ELISA). The high false-positive rate (FPR) of this ELISA prompted us to reexamine its interpretation. METHODS: We analyzed anti-PF4/H ELISA results from a previously published dataset of 1,958 patients, using clinical suspicion and serotonin-release assay (SRA) to diagnose HIT. We performed receiver operating characteristic (ROC) analysis using stratum-specific likelihood ratios (SSLRs) and used Bayes theorem to construct a clinical decision-support algorithm. RESULTS: The most discriminant single cutoff by anti-PF4/H ELISA for the diagnosis of HIT was found to be 0.8 optical density (OD) units, not 0.4 OD (currently accepted practice). This change reduced the FPR from 31% to 6% (95% CI, 5%-8%). ELISA results were grouped into five strata, which yielded SSLRs ranging from 0.02 (strongly ruling HIT out) to 104.4 (strongly ruling HIT in). Comparison of ROC curves demonstrated that this five-strata approach is statistically more accurate than current accepted practice at discriminating whether patients have HIT or not (area under the ROC curve, 0.97 [95% CI, 0.93-1.00] vs 0.83 [95% CI, 0.80-0.89]). Our decision-support algorithm incorporated clinical assessment into this stratified model and clarified HIT diagnosis with a high degree of certainty and without the need for SRA testing in approximately 90% of patients. CONCLUSIONS: Diagnostic accuracy of the anti-PF4/H ELISA can be optimized by using a higher cutoff and a stratified interpretation of the results. Our algorithm should significantly reduce overdiagnosis of HIT and the need for SRA testing.

Hemophagocytic lymphohistiocytosis: a potentially underrecognized association with systemic inflammatory response syndrome, severe sepsis, and septic shock in adults.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) was originally described as a genetic disorder of immune regulation, presenting in neonates with protracted fever, hepatosplenomegaly, and cytopenia. A secondary form of HLH, triggered by serious infections, was subsequently described in adults. METHODS: We report three adult patients who presented with systemic inflammatory response syndrome and features consistent with severe sepsis and septic shock, who subsequently received a diagnosis of secondary HLH. We reviewed the relationship between infection-triggered HLH and septic shock from the perspective of the adult intensivist. RESULTS: The hyperinflammatory pathophysiologic characteristics of HLH and septic shock are closely intertwined. Clinical and laboratory features of HLH and septic shock overlap in some patients, making the syndromes difficult to distinguish. In our experience and review, progressive pancytopenia was the feature most likely to suggest secondary HLH in the adult patient with presumed (or definite) septic shock. Use of other HLH-2004 diagnostic criteria is hindered by the poor operating characteristics of these tests in critically ill adults. Bone marrow aspiration is the most useful diagnostic test, but may yield an initial false-negative result. CONCLUSION: The HLH-2004 treatment protocol is not of proven benefit in critically ill adults, but observational data suggest that aggressive immunosuppressive therapy should not be delayed. Further study of HLH in the critical care setting might provide important insights into the pathogenesis and clinical treatment of sepsis.

Results of a protocol for the management of patients with fulminant liver failure.

OBJECTIVE: To assess the safety and efficacy of a protocol to support management of intracerebral pressure in patients with fulminant liver failure (FLF). DESIGN AND SETTING: A prospective series was conducted between May 2004 and September 2006 at Banner Good Samaritan Medical Center, a 650-bed teaching hospital in Phoenix, Arizona. PATIENTS: We recruited consecutive patients with FLF and stage 3 or 4 encephalopathy. INTERVENTIONS: We placed an intracranial pressure monitor in each patient and employed a protocol to support decisions regarding hemostatic management and prevention and treatment of intracranial hypertension (IHTN). Treatment modalities included hypothermia, hypocarbia, intravenous pentobarbital, intravenous mannitol and vasopressor titration for maintenance of cerebral perfusion pressure. The main outcome measure was survival in transplant candidates. MEASUREMENTS AND MAIN RESULTS: Twenty-two patients entered the study and 21 (95%) had at least one episode of IHTN. Eighty-two discrete episodes of IHTN occurred, and 78 of these (95%) resolved with treatment. Overall survival was 55%. Eleven of 18 (61%) of transplant candidates survived with good neurologic outcome. No patient died from isolated cerebral edema. Three patients had intracranial hemorrhages related to the intracranial pressure monitor. CONCLUSIONS: Protocol-driven management of intracranial pressure in FLF can result in good clinical outcomes in most transplant candidates, even if IHTN occurs.