Medical-surgical ICU Patients Research Articles

Effects of sodium bicarbonate infusion on mortality in medical-surgical ICU patients with metabolic acidosis-A single-center propensity score matched analysis.

Metabolic acidosis is associated with high mortality. Despite theoretical benefits of sodium-bicarbonate (SB), current evidence remains controversial. We investigated SB-related effects on outcomes in ICU patients with metabolic acidosis. Retrospective analysis. Academic medical center. 971 ICU patients with metabolic acidosis defined as arterial pH<7.3 and CO2<45mmHg treated between 2012 and 2016. A propensity score (PS) was estimated using logistic regression. Patients were matched in pairs using the PS. 441 patients were treated with SB 8.4% (SB-group) and n=530 patients were not (control group). Primary outcome was all-cause mortality at ICU-discharge. Average Treatment Effect (ATE), Average Treatment effect in Treated (ATT), and estimated relative survival effects at 20 days were computed. In the full cohort, we observed considerable differences in pH, base excess, additional acidosis-related indices, and ICU mortality (controls 31% vs. SB-group 56%, p<.001) at baseline between the two groups. After PS-matching (n=174 in each group), no significant difference in ICU mortality was observed (controls 32% vs. SB-group 41%; p=.07). Odds ratios (OR) for ATE and ATT showed no association with ICU mortality (OR ATE: 1.08, 95%-CI 0.99-1.17; p=.08; OR ATT 1.09; 95%-CI 0.99-1.2; p=.09). Hazard ratios at 20-days (multivariable HR, matched sample n=348: 1.16, 95%-CI 0.86-1.56, p=.33) showed similar survival in the two study groups. We did not observe effects of SB infusion on all-cause mortality in critically ill patients with metabolic acidosis.

Effects of sodium bicarbonate infusion on mortality in medical–surgical ICU patients with metabolic acidosis—A single-center propensity score matched analysis

ObjectiveMetabolic acidosis is associated with high mortality. Despite theoretical benefits of sodium-bicarbonate (SB), current evidence remains controversial. We investigated SB-related effects on outcomes in ICU patients with metabolic acidosis. DesignRetrospective analysis. SettingAcademic medical center. Patients or participants971 ICU patients with metabolic acidosis defined as arterial pH<7.3 and CO2<45mmHg treated between 2012 and 2016. A propensity score (PS) was estimated using logistic regression. Patients were matched in pairs using the PS. Interventions441 patients were treated with SB 8.4% (SB-group) and n=530 patients were not (control group). Main variables of interestPrimary outcome was all-cause mortality at ICU-discharge. Average Treatment Effect (ATE), Average Treatment effect in Treated (ATT), and estimated relative survival effects at 20 days were computed. ResultsIn the full cohort, we observed considerable differences in pH, base excess, additional acidosis-related indices, and ICU mortality (controls 31% vs. SB-group 56%, p<.001) at baseline between the two groups. After PS-matching (n=174 in each group), no significant difference in ICU mortality was observed (controls 32% vs. SB-group 41%; p=.07). Odds ratios (OR) for ATE and ATT showed no association with ICU mortality (OR ATE: 1.08, 95%-CI 0.99–1.17; p=.08; OR ATT 1.09; 95%-CI 0.99–1.2; p=.09). Hazard ratios at 20-days (multivariable HR, matched sample n=348: 1.16, 95%-CI 0.86–1.56, p=.33) showed similar survival in the two study groups. ConclusionsWe did not observe effects of SB infusion on all-cause mortality in critically ill patients with metabolic acidosis.

Dysphagia Post-Extubation Affects Long-Term Mortality in Mixed Adult ICU Patients-Data From a Large Prospective Observational Study With Systematic Dysphagia Screening.

OBJECTIVES:Data on long-term effects of post-extubation dysphagia is lacking. We investigate mid- and long-term clinical outcomes in a large sample of ICU patients with systematic dysphagia screening.DESIGN:Outcome analysis with a follow-up of 6 years or death (whichever occurred earlier) of ICU patients from a prospective observational trial (Dysphagia in Mechanically Ventilated ICU Patients study) with systematic dysphagia screening.SETTING:ICU of a tertiary care academic center.PATIENTS:Nine-hundred thirty-three mixed medical-surgical ICU patients (median age, 66 yr; interquartile range [IQR], 54–74, Acute Physiology and Chronic Health Evaluation II score 19 [IQR, 14–24], 71% male).INTERVENTIONS:ICU patients were followed up for a mean follow-up period of 1,731 ± 772 days (4.7 ± 2.1 yr). Primary outcome measures were 180-day and 360-day all-cause mortality in ICU patients with versus without dysphagia.MEASUREMENTS AND MAIN RESULTS:Two-hundred seventy-three patients died (29.3%) during the observational interval (n = 76 lost to follow-up). In dysphagia screening positive versus negative ICU patients, mortality at 180 days was 16% versus 5.8% (excess mortality 10.2%), whereas mortality at 360 days was 25% versus 9.1% (excess mortality 15.9%). Adjustment for confounders in a Cox model revealed a significant association of dysphagia with all-cause mortality in a time-dependent manner. The risk of death in ICU patients with versus without post-extubation dysphagia declined from about 2.5 times higher to about equal risk for both groups over the first year (i.e. 1.03 yr) post-ICU admission (at 360 d: hazard ratio [HR], 1.03; 95% CI, 0.42–3.70). The mean mortality HR for the first year post-ICU admission was HR 2.09 (95% CI, 1.34–3.24; p = 0.0009).CONCLUSIONS:Long-term follow-up of a large cohort of medical-surgical adult ICU patients systematically screened for dysphagia showed that dysphagia is associated with increased hazards for death for up to 1 year after ICU admission. Our data underline effects of post-extubation dysphagia on long-term clinical outcomes in affected critically ill patients.

Risk Factors for Dysphagia in ICU Patients After Invasive Mechanical Ventilation

Dysphagia is common and independently predicts death in ICU patients. Risk factors for dysphagia are largely unknown, with sparse data available from mostly small cohorts without systematic dysphagia screening. What are the key risk factors for dysphagia in ICU patients after invasive mechanical ventilation? Post hoc analysis of data from a monocentric prospective observational study (Dysphagia in Mechanically Ventilated ICU Patients [DYnAMICS]) using comprehensive statistical models to identify potential risk factors for postextubation dysphagia. A total of 933 primary admissions of adult medical-surgical ICU patients (median age, 65 years; interquartile range, 54-73; 666 [71%] men) were investigated in a tertiary care academic center. Patients received systematic bedside screening for dysphagia within 3h postextubation. Dysphagia screening positivity (n= 116) was followed within 24h by a confirmatory examination. After adjustment for confounders, baseline neurologic disease (OR, 4.45; 95%CI, 2.74-7.24; P< .01), emergency admission (OR, 2.04; 95%CI, 1.15-3.59; P< .01), days on mechanical ventilation (OR, 1.19; 95%CI, 1.06-1.34; P< .01), days on renal replacement therapy (OR, 1.1; 95%CI, 1-1.23; P= .03), and disease severity (Acute Physiology and Chronic Health Evaluation II score within first 24 h; OR, 1.03; 95%CI, 0.99-1.07; P< .01) remained independent risk factors for dysphagia postextubation. Increased BMI reduced the risk for dysphagia (6%per step increase; OR, 0.94; 95%CI, 0.9-0.99; P= .03). In ICU patients, baseline neurologic disease, emergency admission, and duration of invasive mechanical ventilation appeared as prominent independent risk factors for dysphagia. Because all ICU patients after mechanical ventilation should be considered at risk for dysphagia, systematic screening for dysphagia is recommended in respective critically ill patients. ClinicalTrials.gov; No.: NCT02333201; URL: www.clinicaltrials.govclinicaltrials.gov.

Neuromonitoring of delirium with quantitative pupillometry in sedated mechanically ventilated critically ill patients

BackgroundIntensive care unit (ICU) delirium is a frequent secondary neurological complication in critically ill patients undergoing prolonged mechanical ventilation. Quantitative pupillometry is an emerging modality for the neuromonitoring of primary acute brain injury, but its potential utility in patients at risk of ICU delirium is unknown.MethodsThis was an observational cohort study of medical-surgical ICU patients, without acute or known primary brain injury, who underwent sedation and mechanical ventilation for at least 48 h. Starting at day 3, automated infrared pupillometry—blinded to ICU caregivers—was used for repeated measurement of the pupillary function, including quantitative pupillary light reflex (q-PLR, expressed as % pupil constriction to a standardized light stimulus) and constriction velocity (CV, mm/s). The relationship between delirium, using the CAM-ICU score, and quantitative pupillary variables was examined.ResultsA total of 59/100 patients had ICU delirium, diagnosed at a median 8 (5–13) days from admission. Compared to non-delirious patients, subjects with ICU delirium had lower values of q-PLR (25 [19–31] vs. 20 [15–28] %) and CV (2.5 [1.7–2.8] vs. 1.7 [1.4–2.4] mm/s) at day 3, and at all additional time-points tested (p < 0.05). After adjusting for the SOFA score and the cumulative dose of analgesia and sedation, lower q-PLR was associated with an increased risk of ICU delirium (OR 1.057 [1.007–1.113] at day 3; p = 0.03).ConclusionsSustained abnormalities of quantitative pupillary variables at the early ICU phase correlate with delirium and precede clinical diagnosis by a median 5 days. These findings suggest a potential utility of quantitative pupillometry in sedated mechanically ventilated ICU patients at high risk of delirium.

Postoperative and Ventilator-Associated Pneumonia

Postoperative pneumonia is currently the third most common complication seen in surgical patients and is associated with an increase in both patient morbidity and hospital costs. The incidence of postoperative pneumonia varies among the different surgical subspecialties. A number of evidence-based strategies exist regarding the prevention and management of pneumonia. However, the majority of studies on ventilator-associated pneumonia (VAP) do not specifically focus on surgical patients but rather are based on mixed medical-surgical ICU patients. The aim of this review is to define the incidence, pathogenesis, and risk factors of both postoperative and VAP; determine what pathogens are commonly encountered; discuss treatment methods; and introduce measures that can be implemented in both the surgical wards and the ICU aimed at preventing this complication. This review contains 5 figures, 7 tables, and 64 references. Key Words: antimicrobial therapy, disease prevention, postoperative pneumonia, surgical critical care; ventilator associated pneumonia, culture, prevention, management, bundles, diagnosis

Postoperative and Ventilator-Associated Pneumonia

Postoperative pneumonia is currently the third most common complication seen in surgical patients and is associated with an increase in both patient morbidity and hospital costs. The incidence of postoperative pneumonia varies among the different surgical subspecialties. A number of evidence-based strategies exist regarding the prevention and management of pneumonia. However, the majority of studies on ventilator-associated pneumonia (VAP) do not specifically focus on surgical patients but rather are based on mixed medical-surgical ICU patients. The aim of this review is to define the incidence, pathogenesis, and risk factors of both postoperative and VAP; determine what pathogens are commonly encountered; discuss treatment methods; and introduce measures that can be implemented in both the surgical wards and the ICU aimed at preventing this complication. This review contains 5 figures, 7 tables, and 64 references. Key Words: antimicrobial therapy, disease prevention, postoperative pneumonia, surgical critical care; ventilator associated pneumonia, culture, prevention, management, bundles, diagnosis

Postoperative and Ventilator-Associated Pneumonia

Postoperative pneumonia is currently the third most common complication seen in surgical patients and is associated with an increase in both patient morbidity and hospital costs. The incidence of postoperative pneumonia varies among the different surgical subspecialties. A number of evidence-based strategies exist regarding the prevention and management of pneumonia. However, the majority of studies on ventilator-associated pneumonia (VAP) do not specifically focus on surgical patients but rather are based on mixed medical-surgical ICU patients. The aim of this review is to define the incidence, pathogenesis, and risk factors of both postoperative and VAP; determine what pathogens are commonly encountered; discuss treatment methods; and introduce measures that can be implemented in both the surgical wards and the ICU aimed at preventing this complication. This review contains 5 figures, 7 tables, and 64 references. Key Words: antimicrobial therapy, disease prevention, postoperative pneumonia, surgical critical care; ventilator associated pneumonia, culture, prevention, management, bundles, diagnosis

Improving the adoption of optimal venous thromboembolism prophylaxis in critically ill patients: A process evaluation of a complex quality improvement initiative

PurposeThis study evaluated a complex initiative to increase evidence-based use of low molecular weight heparin for venous thromboembolism prophylaxis among adult medical-surgical ICU patients. Materials and methodsThis study included: quantitative survey and interviews. Participants were healthcare providers within four ICUs. Surveys collected knowledge of evidence underpinning best practice, exposure to the implementation strategies and their perceived utility, and recommendations. The interview expanded on survey topics. Descriptive statistics summarized the data and chi-squared tests were used to compare groups. Qualitative data were analyzed using a blended deductive and inductive coding approach. ResultsProviders had good knowledge of the evidence (range = 58% to 94%). Pharmacist-to-physician reminders (80%), other reminders (50%), and local guidelines (50%) were the most commonly observed strategies. Local champions (76%), on-site education (74%), and computerized decision support system (69%) were perceived to be most helpful. Interviews elicited five themes: provider roles, perceptions of the implementation strategies, facilitators and barriers to uptake of best practice, and recommendations. Assessment of the implementation strategies varied by professional group. ConclusionsThe findings of this process evaluation identified implementation strategies that can improve the use of evidence-informed practices, help interpret outcomes in the context of interventions and guide future quality improvement initiatives.

Association between troponin-I levels and outcome in critically ill patients admitted to non-cardiac intensive care unit with high prevalence of cardiovascular risk factors

BackgroundThe association of troponin-I levels and outcome in medical-surgical ICU patients has been studied before in populations with low to moderate prevalence of cardiovascular risk factors. The objective in this article is to examine the association of troponin-I levels with hospital mortality in patients with high prevalence of cardiovascular risk factors who were admitted with medical-surgical indications to a non-cardiac intensive care unit.MethodsThis was a retrospective study of adult patients admitted to a tertiary medical-surgical ICU between July 2001 and November 2011. Data were extracted from prospectively collected ICU and clinical laboratory databases. Patients were stratified based on the highest troponin-I level in the first 72 h of admission into four groups (Group I < 0.03, Group II = 0.03–0.3, Group III = 0.3–3 and Group IV > 3 ng/mL). Hospital mortality was the primary outcome. To study the association between elevated troponin-I and hospital mortality, we carried out multivariate logistic regression analyses with Group I as a reference group.ResultsDuring the study period, 3368 patients had troponin-I levels measured in the first 72 h, of whom 1293 (38.3%) were diabetic and 1356 (40.2%) were chronically hypertensive. Among the study population, 2719 (81%) had elevated troponin-I levels (0.03 ng/mL and higher). Hospital mortality increased steadily as the troponin-I levels increased. Hospital mortality was 23.4% for Group I, 33.2% for Group II (adjusted odds ratio (aOR) 1.08, 95% confidence interval (CI) 0.84, 1.38), 49.6% for Group III (aOR = 1.64, 95% CI 1.24, 2.17), and 57.4% for Group IV (aOR 1.80, 95% CI 1.30, 2.49). The association of increased mortality with increased troponin level was observed whether patients had underlying advanced heart failure or not. Subgroup analysis showed an increased mortality in patients aged < 50 years, non-diabetics and not on vasopressors.ConclusionIn a population with high prevalence of diabetes and hypertension, elevated troponin-I was frequently observed in medical-surgical critically ill patients, and showed a level-dependent association with hospital mortality.

Association between \u03b2-blocker use and mortality in critically ill patients: a nested cohort study

Backgroundβ-blockers have several indications in critically ill patients and are commonly used. The aim of this study is to examine the relationship between the use of β-blockers in critically ill patients and mortality.MethodsThis was a nested cohort study in which all medical-surgical ICU patients (N = 523) enrolled in a randomized clinical trial of intensive insulin therapy (ISRCTN07413772) were grouped according to β-blocker use during ICU stay. To account for the indication of β-blockers, we constructed a propensity score using selected clinically-relevant and statistically-significant variables related to β-blocker exposure and outcome. The primary endpoints were all-cause ICU and hospital mortality. Secondary endpoints were the development of severe sepsis during ICU stay, ICU and hospital length of stay, and mechanical ventilation duration. Using multivariable models, we adjusted the associations of β-blockers and these outcomes to the propensity score.ResultsOf the 523 patients enrolled in the study, 89 (17.0%) received β-blockers during their ICU stay. There were no significant associations between β-blocker therapy and ICU mortality (adjusted odds ratio [aOR] 1.56, 95% confidence interval [CI] 0.83–2.9, P = 0.16), hospital mortality (aOR 1.09, 95% CI 0.99–1.20, P = 0.73), the risk of ICU-acquired severe sepsis (aOR 1.67, 95% CI 0.95–2.97, P = 0.08), mechanical ventilation duration (P = 0.17), or ICU length of stay (P = 0.22). However, β-blocker use was associated with increased ICU and hospital mortality among nondiabetic patients (aOR 2.93, 95% CI 1.19–7.23, and 2.43, 95% CI 1.05–5.64, respectively).ConclusionsOur study showed that β-blockers during the ICU stay had no significant association with mortality or morbidity. However, β-blocker therapy was associated with increased mortality in non-diabetic patients.Trial registrationISRCTN07413772; (dated 13.07.2005).

Systemic Corticosteroids and Transition to Delirium in Critically Ill Patients.

Corticosteroids are frequently used in critically ill patients. We investigated whether systemic corticosteroid use increases the probability of transitioning to delirium in a large population of mixed medical-surgical ICU patients. Prospective cohort study. A 32-bed medical-surgical ICU at an academic medical center. Critically ill adults (n = 1,112), admitted to the ICU for more than 24 hours without a condition that could hamper delirium assessment. None. Systemic corticosteroid exposure was measured daily and converted to prednisone equivalents (milligrams). Daily mental status was classified as coma, delirium, or an awake without delirium state. Transitions between states were analyzed using a first-order Markov multinomial logistic regression model with 11 different covariables, with the transition from an awake without delirium state to delirium as a primary interest. Among the 1,112 patients, corticosteroids were administered on 35% (3,483/9,867) of the ICU days at a median dose of 50 mg (interquartile range, 25-75 mg) prednisone equivalent. Administration of a corticosteroid, and any increase in the dose of the corticosteroid given on exposure days, was not significantly associated with the transition to delirium (adjusted odds ratio, 1.08; 95% CI, 0.89-1.32 and adjusted odds ratio, 1.00; 95% CI, 0.99-1.01, per 10 mg increase in prednisone equivalent). In a large population of mixed medical-surgical ICU patients, systemic corticosteroid use was not associated with an increased probability of transitioning to delirium.

Application and evaluation of an updated blood glucose protocol in medical-surgical ICU patients

Application and evaluation of an updated blood glucose protocol in medical-surgical ICU patients

Heparin Thromboprophylaxis in Medical-Surgical Critically Ill Patients

Venous thromboembolism prevention during critical illness is a widely used quality metric. The objective of this systematic review was to systematically review the efficacy and safety of heparin thromboprophylaxis in medical-surgical patients in the ICU. We searched EMBASE, MEDLINE, the Cochrane Controlled Trials Register, Clinicaltrials.gov, and personal files through May 2012. Randomized trials in adult medical-surgical ICU patients comparing any heparin (unfractionated heparin or low-molecular-weight heparin) with each other or no anticoagulant prophylaxis, evaluating deep vein thrombosis, pulmonary embolism, major bleeding, or mortality. Independently, in duplicate, we abstracted trial characteristics, outcomes, and risk of bias. Seven trials involved 7,226 patients. Any heparin thromboprophylaxis compared with placebo reduced rates of deep vein thrombosis (pooled risk ratio, 0.51 [95% CI, 0.41, 0.63]; p<0.0001; I=77%) and pulmonary embolism (risk ratio, 0.52 [95% CI, 0.28, 0.97]; p=0.04; I=0%) but not symptomatic deep vein thrombosis (risk ratio, 0.86 [95% CI, 0.59, 1.25]; p=0.43). Major bleeding (risk ratio, 0.82 [95% CI, 0.56, 1.21]; p=0.32; I=50%) and mortality (risk ratio, 0.89 [95% CI, 0.78, 1.02]; p=0.09; I=0%) rates were similar. Compared with unfractionated heparin, low-molecular-weight heparin reduced rates of pulmonary embolism (risk ratio, 0.62 [95% CI, 0.39, 1.00]; p=0.05; I=53%) and symptomatic pulmonary embolism (risk ratio, 0.58 [95% CI, 0.34, 0.97]; p=0.04) but not deep vein thrombosis (risk ratio, 0.90 [95% CI, 0.74, 1.08]; p=0.26; I=0%), symptomatic deep vein thrombosis (risk ratio, 0.87 [95% CI, 0.60, 1.25]; p=0.44; I=0%), major bleeding (risk ratio, 0.97 [95% CI, 0.75, 1.26]; p=0.83; I=0%), or mortality (risk ratio, 0.93 [95% CI, 0.82, 1.04]; p=0.20; I=31%). Trial evidence to date suggests that any type of heparin thromboprophylaxis decreases deep vein thrombosis and pulmonary embolism in medical-surgical critically ill patients, and low-molecular-weight heparin compared with bid unfractionated heparin decreases pulmonary embolism and symptomatic pulmonary embolism. Major bleeding and mortality rates do not appear to be significantly influenced by heparin thromboprophylaxis in the ICU setting. Trial methodology, indirectness, and the heterogeneity and imprecision of some results temper inferences from this literature.

In medical-surgical ICU patients, major bleeding is common but independent of heparin prophylaxis

Bleeding frequently complicates critical illness. Our objectives were to describe the incidence, locations and predictors of major bleeding in patients with low risk of bleeding receiving thromboprophylaxis.

4Ts HIT Scoring in the Medical-Surgical ICU

Abstract 4669 Background:Thrombocytopenia occurs in 20–45% of critically-ill medical-surgical patients. The ‘4Ts' HIT score (with 4 domains: Thrombocytopenia, Timing of thrombocytopenia, Thrombosis and oTher reason for thrombocytopenia) might reliably identify patients at low risk of HIT. Agreement on 4Ts scoring is uncertain in this setting. Objective:To compare 4Ts HIT scores among research coordinators (who scored real-time), and 2 adjudicators (who scored retrospectively, independently) during an international heparin thromboprophylaxis trial. Methods:763 of 3746 medical-surgical ICU patients in PROTECT met enrolment criteria in this HIT substudy, if any of the following occurred: platelets <50×109/L, platelets decreased to 50% of ICU admission value, venous thrombosis, or if HIT was otherwise clinically suspected. Persons independently completed 4Ts scores blinded to all laboratory HIT results and each others’ scores. 475 of these patients had a central or local laboratory HIT test performed and had 4Ts scoring by adjudicators; 432 were scored by research coordinators. Results:Most patients (410, 86.3%) had a 4Ts score ≤3 conferring a low pretest probability (PTP) of HIT whereas 57 (12.0%) had a moderate PTP, and 8 (1.7%) had a high PTP, as determined by adjudicator consensus. Raw agreement on the 4Ts score was good for central adjudicators overall; however, agreement between adjudicated consensus scores and real time research coordinator scores was not as high. 4Ts agreement (raw and chance-corrected) is presented below.Adjudicator A vs B (N = 475)Adjudicator Consensus vs Research Coordinator (N=432)RawKappaWeighted kappaRawKappaWeighted kappaQ1. Thrombocytopenia92.0%0.860.9376.9%0.600.78Q2. Timing82.3%0.600.6871.1%0.390.47Q3. Thrombosis92.8%0.860.9184.0%0.700.78Q4. Other73.9%0.250.3160.6%0.100.13Total (low/ intermed/high)80.8%0.330.4171.5%0.190.23 Conclusions:Real time 4Ts scoring by research coordinators was reasonably close to that obtained by calibrated central adjudicators, suggesting the 4Ts score is somewhat reliable at the bedside when performed by trained personnel. The fourth domain of 4Ts (oTher causes of thrombocytopenia) generated the most disagreement. Further studies of 4Ts scoring by bedside clinicians is needed. Funding:Heart and Stroke Foundation of Canada Disclosures:Crowther:Pfizer: Consultancy, Honoraria; Leo Pharma: Consultancy, Honoraria; Bayer: Consultancy, Honoraria; BI: Honoraria; CSL Behring: Consultancy; Octaphram: Consultancy; Artisan: Consultancy. Off Label Use: Dalterparin is not indicated for prolonged prophylaxis in critically ill medical patients. Zytaruk:Pfizer: donated study drug dalteparin for PROTECT. Cook:Pfizer: donated study drug dalteparin for PROTECT. Warkentin:Sanofi-Aventis: Speakers Bureau; Pfizer Canada: Speakers Bureau; GlaxoSmithKline: Consultancy, Research Funding; GTI Diagnostics: Consultancy, Research Funding; Canyon Pharma: Consultancy, Speakers Bureau; Informa: Patents & Royalties.

Laboratory HIT Testing in Critically Ill Patients

Abstract 198▪FN2▪This icon denotes a clinically relevant abstract Introduction:Many critically ill patients are frequently suspected of having HIT because heparin exposure is nearly universal and up to 45% of medical-surgical ICU patients have a platelet count of less than 150 × 109. Methods:Our objectives were: (1) To estimate the incidence of suspected and objectively confirmed HIT; and (2) To evaluate whether a published clinical prediction rule (the 4T’s score) reliably rules out HIT in ‘low risk’ ICU patients. PROTECT was a multinational, concealed, stratified, randomized blinded trial enrolling medical-surgical critically ill patients to evaluate thromboprophylaxis with the low molecular weight heparin (LMWH) dalteparin 5,000U daily vs unfractionated heparin (UFH) 5,000 twice daily on the primary outcome of proximal leg deep vein thrombosis (DVT). Patients were evaluated for HIT and included in this HITEC Substudy if 1) their platelet count decreased to less than 50 × 109/L, 2) if there was an otherwise unexplained platelet count decrease to less than 50% of the patient’s baseline (defined as the value found on the first platelet count after ICU admission as long as the count is >100 × 109/L), or 3) if venous thrombosis occurred, and 4) if HIT was otherwise suspected. There were 2 laboratory components to HIT testing (local and central). For local real-time clinical care, HIT was evaluated and treated as per local practice. Centrally, blood samples were analyzed at the laboratory of Dr Ted Warkentin at McMaster University. The 4Ts Score was completed by Research Coordinators (RCs) and by central adjudication. We defined HIT as a clinical suspicion of HIT and a positive serotonin release assay (SRA). Results:The PROTECT trial enrolled 3746 patients of whom 763 patients (397 allocated to UFH and 366 to LMWH) met HITEC enrollment criteria; 151 because of an absolute platelet count of less than 50×109, 253 because of a fall in their platelet count of greater than 50% from the time of ICU admission and 534 because venous thrombosis developed and 128 because of a clinical suspicion of HIT (categories are not mutually exclusive). Of these 763 patients, 475 had a central or local laboratory HIT test performed and were adjudicated. HIT was present in 15/3746 patients enrolled in the PROTECT study (0.4%, 95% CI 0.2% to 0.7%), and 15/475 (3.2%) with local or central testing, while 432 patients with RC 4Ts scores were matched to an adjudicated outcome. Using the 4Ts score, RCs and central adjudication classified patients as low risk (4Ts score of 3 or less) in 71.1% and 86.3% of cases, respectively, moderate risk (score or 4 or 5) in 25.7% and 12.0% of cases, and high risk (score of 6 or more) in 3.2% and 1.7% of cases. There was a good correlation between a low pretest probability according to the RCs’ scores and the absence HIT (prevalence of adjudication confirmed HIT 1.6% (95% CI 0.5 to 3.7%).There was a moderate correlation between a low pretest probability according to central adjudication and the absence HIT (prevalence of adjudication confirmed HIT 2.6% (1.3 to 4.7%). Discussion:HIT occured in less than 1% of medical-surgical critically ill patients, and in 3% of patients who had at least one criterion to suspect HIT. We failed to confirm our pre-specified criteria for successful implementation of the 4T's score (that the upper boundary the 95% confidence interval about the proportion of patients with confirmed HIT and a low 4Ts score was less than 3%) and thus we conclude that use of the 4Ts score does not rule out the presence of platelet-activating antibodies in medical surgical critically ill patients with clinically suspected HIT; SRA testing is recommended. Funding:Canadian Institutes for Health Research and Heart and Stroke Foundation of Canada Disclosures:Crowther:CSL Behring: Consultancy; Leo Pharma: Consultancy, Research Funding; BI: Research Funding; Bayer: Research Funding; Pfizer: Consultancy, Research Funding; Octapharm: Consultancy; Artisan: Consultancy. Off Label Use: Dalteparin is not indicated for prolonged DVT prophylaxis in medical intensive care unit patients. Zytaruk:Pfizer: donated study drug dalteparin for PROTECT. Cook:Pfizer: donated study drug dalteparin for PROTECT. Warkentin:GTI Diagnostics: Consultancy, Research Funding; GlaxoSmithKline: Consultancy, Research Funding; Pfizer Canada: Speakers Bureau; Sanofi-Aventis: Speakers Bureau; Informa: Patents & Royalties; Canyon Pharma: Consultancy, Speakers Bureau.

Pulmonary embolism in medical-surgical ICU patients

Pulmonary embolism (PE) is a feared complication of critical illness. PE is difficult to diagnose during critical illness due to the nonspecificity of signs and symptoms and low index of suspicion in practice. Our objective was to examine the antecedent characteristics and hospital course of patients who were diagnosed with PE during critical illness in the context of an international trial of thromboprophylaxis ({type:clinical-trial,attrs:{text:NCT00182143,term_id:NCT00182143}}NCT00182143).

Antiembolic stockings and pneumatic compression devices in a medical-surgical thromboprophylaxis trial

A recent randomized trial (CLOTS-1) has called into question the utility of antiembolic stockings (AESs); another trial (CLOTS-2) suggested harm with below-knee compared with above-knee AESs. AESs and pneumatic compression devices (PCD)s could represent important co-interventions in a heparin thromboprophylaxis trial if exposure was lengthy and frequent. Our objective was to document the use of AESs and PCDs applied per protocol and by protocol violation in a trial comparing UFH versus LMWH in medical-surgical ICU patients ({type:clinical-trial,attrs:{text:NCT00182143,term_id:NCT00182143}}NCT00182143).

Pulmonary embolism in medical-surgical ICU patients

Pulmonary embolism (PE) is a feared complication of critical illness. PE is difficult to diagnose during critical illness due to the nonspecificity of signs and symptoms and low index of suspicion in practice. Our objective was to examine the antecedent characteristics and hospital course of patients who were diagnosed with PE during critical illness in the context of an international trial of thromboprophylaxis ({type:clinical-trial,attrs:{text:NCT00182143,term_id:NCT00182143}}NCT00182143).