Mark Thoelke

Efficacy and safety of high-dose thromboprophylaxis in morbidly obese inpatients

Obesity increases the risk for venous thromboembolism (VTE), but whether high-dose thromboprophylaxis is safe and effective in morbidly obese inpatients is unknown. It was the objective of this study to quantify the efficacy and safety of high-dose thromboprophylaxis with heparin or enoxaparin in inpatients with weight > 100 kilograms (kg) within the BJC HealthCare system. Ina retrospective cohort study, we analysed 9,241 inpatients with weight > 100 kg discharged from three hospitals in the BJC HealthCare system from 2010 through 2012. We compared the incidence of VTE in patients who received high-dose thromboprophylaxis (heparin 7,500 units three times daily or enoxaparin 40 mg twice daily) to those who received standard doses (heparin 5,000 units two or three times daily or enoxaparin 40 mg once daily). The primary efficacy outcome was hospital-acquired VTE identified by International Classification of Diseases (ICD)-9 diagnosis codes. The primary safety outcome was bleeding events identified by ICD-9 codes. Among the 3,928 morbidly obese inpatients (weight > 100 kg and body mass index [BMI] ≥ 40 kg/m²), high-dose thromboprophylaxis approximately halved the odds of symptomatic VTE (odds ratio [OR] 0.52, 95% confidence interval [CI] 0.27-1.00; p = 0.050). The rate of VTE was 1.48% (35/2,369) in these morbidly obese inpatients who received standard doses of thromboprophylaxis, compared to 0.77% (12/1,559) in those who received high doses. High-dose thromboprophylaxis did not increase bleeding (OR 0.84, 95% CI 0.66-1.07, p = 0.15). Independent predictors of VTE were surgery, male sex, cancer, and BMI. In conclusion, high-dose thromboprophylaxis nearly halves the rate of VTE in morbidly obese inpatients.

Risk factors for inpatient venous thromboembolism despite thromboprophylaxis

INTRODUCTION Venous thromboembolism (VTE) is the most common preventable cause of morbidity and mortality in the hospital. Adequate thromboprophylaxis has reduced the rate of hospital-acquired VTE substantially; however, some inpatients still develop VTE even when they are prescribed thromboprophylaxis. Predictors associated with thromboprophylaxis failure are unclear. In this study, we aimed to identify risk factors for inpatient VTE despite thromboprophylaxis. MATERIALS AND METHODS We conducted a case-control study to identify independent predictors for inpatient VTE. Among patients discharged from the BJC HealthCare system between January 2010 and May 2011, we matched 94 cases who developed in-hospital VTE while taking thromboprophylaxis to 272 controls who did not develop VTE. Matching was done by hospital, patient age, month and year of discharge. We used multivariate conditional logistic regression to develop a VTE prediction model. RESULTS We identified five independent risk factors for in-hospital VTE despite thromboprophylaxis: hospitalization for cranial surgery, intensive care unit admission, admission leukocyte count >13,000/mm(3), presence of an indwelling central venous catheter, and admission from a long-term care facility. CONCLUSIONS We identified five risk factors associated with the development of VTE despite thromboprophylaxis in the hospital setting. By recognizing these high-risk patients, clinicians can prescribe aggressive VTE prophylaxis judiciously and remain vigilant for signs or symptoms of VTE.

Prevention of inpatient hypoglycemia with a real-time informatics alert.

BACKGROUND Severe hypoglycemia (SH), defined as a blood glucose (BG) <40 mg/dL, is associated with an increased risk of adverse clinical outcomes in inpatients. OBJECTIVE To determine whether a predictive informatics hypoglycemia risk-alert supported by trained nurse responders would reduce the incidence of SH in our hospital. DESIGN A 5-month prospective cohort intervention study. SETTING Acute care medical floors in a tertiary care academic hospital in St. Louis, Missouri. PATIENTS From 655 inpatients on designated medical floors with a BG of <90 mg/dL, 390 were identified as high risk for hypoglycemia by the alert system. MEASUREMENTS The primary outcome was the incidence of SH occurring in high-risk intervention versus high-risk control patients. Secondary outcomes included: number of episodes of SH in all study patients, incidence of BG < 60 mg/dL and severe hyperglycemia with a BG >299 mg/dL, length of stay, transfer to a higher level of care, the frequency that high-risk patients orders were changed in response to the alert-intervention process, and mortality. RESULTS The alert process, when augmented by nurse-physician collaboration, resulted in a significant decrease by 68% in the rate of SH in alerted high-risk patients versus nonalerted high-risk patients (3.1% vs 9.7%, P = 0.012). Rates of hyperglycemia were similar on intervention and control floors at 28% each. There was no difference in mortality, length of stay, or patients requiring transfer to a higher level of care. CONCLUSION A real-time predictive informatics-generated alert, when supported by trained nurse responders, significantly reduced inpatient SH.

Generalised insulin oedema after intensification of treatment with insulin analogues.

We report a case of generalised insulin oedema after intensification of treatment with genetically modified insulin. This is the first case of generalised oedema in response to treatment with insulin analogues in a patient not insulin naive.

Concurrent Ramsay Hunt syndrome and disseminated herpes zoster in a patient with relapsed chronic lymphocytic leukemia

Ramsay Hunt Syndrome (RHS) is a rare complication of latent varicella-zoster virus (VZV) infection that can occur in immunocompetent host. It usually involves ipsilateral facial paralysis, ear pain and facial vesicles. Disseminated herpes zoster is another complication of VZV infection typically seen in immunocompromised hosts. We describe a patient with relapsed chronic lymphocytic leukemia (CLL) who presented simultaneously with RHS and disseminated herpes zoster. While other complications have been documented to coexist with RHS, to our knowledge, this is the first reported case in the literature of concurrent RHS with disseminated herpes zoster.

Impact of Vitamin K Administration on INR Changes and Bleeding Events Among Patients With Cirrhosis

Background: The efficacy of vitamin K in lowering an elevated INR in the setting of cirrhosis is not well established. Objectives: The purpose of this investigation is to determine the effect of vitamin K administration on the INR and bleeding eventsamong hospitalized patients with cirrhosis. Methods: This is a retrospective investigation of patients hospitalized at an academic institution from 2010 to 2012. Adults with an ICD9 code supporting cirrhosis were segregated into matched cohorts based on provision of vitamin K. Multivariable logistic regression of factors associated with INR decrease and bleeding events was completed. Results: The final matched cohort (n = 276) contained 130 patients who received vitamin K and 146 who did not receive this therapy. ICU care (adjusted odds ratio [AOR] = 2.91; 95% CI = 1.54-5.49; P = 0.01), receipt of a blood product (AOR = 2.40; 95%CI = 1.35-4.24; P = 0.03), and baseline INR > 1.6 (AOR = 1.72; 95% CI = 1.00-2.95; P = 0.05), but not vitamin K administration (AOR = 1.17; 95% CI = 0.66-2.08; P = 0.59), were associated with INR decrease. Bleeding events occurred more frequently among patients with a history of esophageal varices (AOR = 6.35; 95% CI = 1.21-33.4; P = 0.03), but vitamin K administration did not have an impact on these events (AOR = 4.90; 95% CI = 0.56-43.0; P = 0.15). Conclusions: Administration of vitamin K did not affect INR changes or bleeding events in this cohort of hospitalized patients with cirrhosis.

A Single, Post-ACTH Cortisol Measurement to Screen for Adrenal Insufficiency in the Hospitalized Patient

BACKGROUND Cosyntropin stimulation testing (CST) is used to screen patients for adrenal insufficiency (AI). Traditionally, CST includes baseline cortisol concentration, the administration of cosyntropin, and cortisol concentration at 30 and 60 minutes poststimulation. There is debate surrounding the utility of testing and cut-off points for concentrations at each time point. OBJECTIVE To determine if a single cortisol measurement at 30 or 60 minutes could replace the traditional approach. DESIGN We looked retrospectively at inpatients who underwent standard, high-dose CST (n = 702) and evaluated the number of patients who would screen positive for AI by using a single time point (30 or 60 minutes) compared with the traditional CST. SETTING A tertiary-care, academic medical center. PATIENTS Hospital inpatients present between January 2012 and September 2013. RESULTS Of tests, 84.3% were normal, which was defined as at least one cortisol concentration of 18 mcg/dL or higher at any time after stimulation. The average 60-minute concentration was higher than the average 30-minute concentration (P < .001). A single 60-minute concentration is 100% concordant with the full CST in the intensive care unit (ICU) subgroup and 99.6% concordant in floor patients. A single 30-minute concentration is significantly less concordant, 91.9% and 86.9%, in the ICU and floor subgroups, respectively. CONCLUSIONS Overall, a single 60-minute cortisol concentration to screen for AI was 99.7% concordant with the traditional CST, and the positive percent agreement was 98%. Fewer false-positive screens would occur with a single 60-minute cortisol concentration compared with a single 30-minute concentration (P < .001). High-dose CST screening may safely be interpreted with single 60-minute poststimulation cortisol serum concentrations.

Analysis of Enoxaparin Dose Titration at a Large, Tertiary Teaching Facility

Therapeutic drug monitoring of enoxaparin with antifactor Xa levels (AXALs) is recommended in some populations; however, the approach to dose titration is poorly described. Our study at a large, tertiary teaching facility examined the dose response to titration of enoxaparin based on AXAL. Patients from 2008 to 2012 receiving enoxaparin were included, provided 2 or more steady state AXAL were obtained within 30 days and that the enoxaparin was prescribed for treatment rather than prophylaxis. The primary outcome was the percentage of dose change required to obtain goal range AXAL following dose titration. Eighty-seven patients were available for analysis with the following key characteristics: renal dysfunction during treatment 72%, obesity 8%, and solid organ transplant 26%. Initial goal AXAL was attained in 27 (31%) patients, and ultimately 54 (62%) patients achieved goal AXAL. Of the 31 patients who had initial AXAL above goal, 13 (42%) patients reached goal with a median dose decrease of 24%. In the 29 patients who had an initial AXAL below goal, 11 (38%) achieved therapeutic AXAL with a median dose increase of 16%. The AXAL monitoring can guide enoxaparin titration with subtherapeutic or supratherapeutic AXAL and an increase or decrease of roughly 20% is suggested as an initial change.