Correlation Between Serum and CSF Concentrations of Midazolam and 1-Hydroxy-Midazolam in Critically Ill Neurosurgical Patients.

BACKGROUND: Midazolam (MZ) is commonly used in critically ill neurosurgical patients. Neuro-penetration of MZ and its metabolite, 1-hydroxy-midazolam (1-OH-MZ), is not well characterized. OBJECTIVE: This study evaluated correlations between serum and cerebrospinal fluid (CSF) concentrations of MZ and 1-OH-MZ and assessed implications on patient sedation. METHODS: Adults in the neurosurgical intensive care unit (ICU) with external ventricular drains receiving MZ via continuous infusion were prospectively studied. Serum and CSF samples were obtained 12-24 h and 72-96 h after initiation, and concentrations were determined in duplicate by high-performance liquid chromatography with tandem mass spectrometry. Bivariate correlation analyses used Pearson coefficient. RESULTS: A total of 31 serum and CSF samples were obtained from 18 subjects. At sampling, mean MZ infusion rate was 3.9 ± 4.4 mg/h, and previous 12-h cumulative dose was 51.4 ± 78.2 mg. Mean concentrations of MZ and 1-OH-MZ in serum and CSF were similar between timepoints. Similarly, ratios of 1-OH-MZ to MZ in serum and CSF remained stable over time. Serum MZ (126.2 ± 89.3 ng/mL) showed moderate correlation (r2 = 0.68, P < 0.001) with serum 1-OH-MZ (17.7 ± 17.6 ng/mL) but not CSF MZ (3.9 ± 2.5 ng/mL; r2 = 0.24, P = 0.005) or CSF 1-OH-MZ (2.5 ± 0.6 ng/mL; r2 = 0.47, P = 0.30). CSF MZ did not correlate with CSF 1-OH-MZ (r2 = 0.003, P < 0.001). Mean serum ratio of 1-OH-MZ to MZ (0.14 ± 0.2 ng/mL) did not correlate with CSF ratio (1.06 ± 0.83 ng/mL; r2 = 0.06, P = 0.19). Concentrations and ratios were unrelated to MZ infusion rate or 12-h cumulative dose. Sedation was weakly correlated with CSF 1-OH-MZ, but not with serum MZ, serum 1-OH-MZ, or CSF MZ. CONCLUSION AND RELEVANCE: Continuous infusions of MZ result in measurable concentrations of MZ and 1-OH-MZ in CSF; however, CSF concentrations of MZ and 1-OH-MZ poorly represent serum concentrations or dosages. Accumulation of MZ and 1-OH-MZ in serum or CSF over time was not evident. Concentrations of MZ and 1-OH-MZ do not predict sedation levels, reinforcing that pharmacodynamic assessments are warranted.

Correlation Between and Nursing Satisfaction With CIWA-Ar, mMINDS, and SEWS Scoring Tools for the Assessment of Severe Alcohol Withdrawal Syndrome in ICU Patients.

BACKGROUND: Management of alcohol withdrawal syndrome (AWS) requires bedside assessments of symptom severity to guide therapies. Commonly used assessment tools are the Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar), the modified Minnesota Detoxification Scale (mMINDS) and the Severity of Ethanol Withdrawal Scale (SEWS). OBJECTIVE: To determine strength of correlation between the CIWA-Ar, mMINDS, and SEWS for bedside assessment of severe AWS and to survey nurses regarding ease of use of each tool. METHODS: A single-center prospective correlation study of the three assessment tools performed by bedside nurses on patients with AWS followed by a questionnaire assessing ease of use of each tool (1 being the easiest and 9 being the hardest). RESULTS: A total of 66 correlation assessments were performed by 49 nurses in 21 patients with AWS. Bedside CIWA-Ar, mMINDS, and SEWS were 14 ± 8.3, 13.9 ± 6.5, and 10.1 ± 4.5, respectively. The Pearson correlation coefficients were 0.814 (95% CI, 0.714-0.881) between CIWA-Ar and mMINDS; 0.722 (95% CI, 0.585-0.820) between CIWA-Ar and SEWS; and 0.658 (95% CI, 0.498-0.775) between SEWS and mMINDS. Nurse ratings for ease of use were 4 ± 2.3 for CIWA-Ar, 2.9 ± 2 for mMINDS (p=0.0044 vs. CIWA-Ar), and 4.8 ± 2.1 for SEWS (p=0.036 vs. CIWA-Ar, p<0.0001 vs. mMINDS). Forty-six (69.7%) respondents preferred mMINDS versus 14 (21.2%) and 6 (9.1%) respondents favored CIWA-Ar and SEWS, respectively. CONCLUSION: Correlations between the three scoring tools in severe AWS are robust. Only mMINDS was considered easy to use by nurses. It was the preferred tool.

A methodology of phenotyping ICU patients from EHR data: High-fidelity, personalized, and interpretable phenotypes estimation.

OBJECTIVE: Computing phenotypes that provide high-fidelity, time-dependent characterizations and yield personalized interpretations is challenging, especially given the complexity of physiological and healthcare systems and clinical data quality. This paper develops a methodological pipeline to estimate unmeasured physiological parameters and produce high-fidelity, personalized phenotypes anchored to physiological mechanics from electronic health record (EHR). METHODS: A methodological phenotyping pipeline is developed that computes new phenotypes defined with unmeasurable computational biomarkers quantifying specific physiological properties in real time. Working within the inverse problem framework, this pipeline is applied to the glucose-insulin system for ICU patients using data assimilation to estimate an established mathematical physiological model with stochastic optimization. This produces physiological model parameter vectors of clinically unmeasured endocrine properties, here insulin secretion, clearance, and resistance, estimated for individual patient. These physiological parameter vectors are used as inputs to unsupervised machine learning methods to produce phenotypic labels and discrete physiological phenotypes. These phenotypes are inherently interpretable because they are based on parametric physiological descriptors. To establish potential clinical utility, the computed phenotypes are evaluated with external EHR data for consistency and reliability and with clinician face validation. RESULTS: The phenotype computation was performed on a cohort of 109 ICU patients who received no or short-acting insulin therapy, rendering continuous and discrete physiological phenotypes as specific computational biomarkers of unmeasured insulin secretion, clearance, and resistance on time windows of three days. Six, six, and five discrete phenotypes were found in the first, middle, and last three-day periods of ICU stays, respectively. Computed phenotypic labels were predictive with an average accuracy of 89%. External validation of discrete phenotypes showed coherence and consistency in clinically observable differences based on laboratory measurements and ICD 9/10 codes and clinical concordance from face validity. A particularly clinically impactful parameter, insulin secretion, had a concordance accuracy of 83%±27%. CONCLUSION: The new physiological phenotypes computed with individual patient ICU data and defined by estimates of mechanistic model parameters have high physiological fidelity, are continuous, time-specific, personalized, interpretable, and predictive. This methodology is generalizable to other clinical and physiological settings and opens the door for discovering deeper physiological information to personalize medical care.

Correlation of antimicrobial fraction unbound and sieving coefficient in critically ill patients on continuous renal replacement therapy: a systematic review.

BACKGROUND: Fraction unbound has been used as a surrogate for antimicrobial sieving coefficient (SC) to predict extracorporeal clearance in critically ill patients on continuous renal replacement therapy (CRRT), but this is based largely on expert opinion. OBJECTIVES: To examine relationships between package insert-derived fraction unbound (Fu-P), study-specific fraction unbound (Fu-S), and SC in critically ill patients receiving CRRT. METHODS: English-language studies containing patient-specific in vivo pharmacokinetic parameters for antimicrobials in critically ill patients requiring CRRT were included. The primary outcome included correlations between Fu-S, Fu-P, and SC. Secondary outcomes included correlations across protein binding quartiles, serum albumin, and predicted in-hospital mortality, and identification of predictors for SC through multivariable analysis. RESULTS: Eighty-nine studies including 32 antimicrobials were included for analysis. SC was moderately correlated to Fu-S (R2 = 0.55, P < 0.001) and Fu-P (R2 = 0.41, P < 0.001). SC was best correlated to Fu-S in first (<69%) and fourth (>92%) quartiles of fraction unbound and above median albumin concentrations of 24.5 g/L (R2 = 0.71, P = 0.07). Conversely, correlation was weaker in patients with mortality estimates greater than the median of 55% (R2 = 0.06, P = 0.84). SC and Fu-P were also best correlated in the first quartile of antimicrobial fraction unbound (R2 = 0.66, P < 0.001). Increasing Fu-P, flow rate, membrane surface area, and serum albumin, and decreasing physiologic charge significantly predicted increasing SC. CONCLUSIONS: Fu-S and Fu-P were both reasonably correlated to SC. Caution should be taken when using Fu-S to calculate extracorporeal clearance in antimicrobials with 69%-92% fraction unbound or with >55% estimated in-hospital patient mortality. Fu-P may serve as a rudimentary surrogate for SC when Fu-S is unavailable.

Evaluation of safety and efficacy outcomes of direct oral anticoagulants versus warfarin in normal and extreme body weights for the treatment of atrial fibrillation or venous thromboembolism.

Despite evolving evidence, the use of direct oral anticoagulants (DOACs) in patients with extremes of body weight remains controversial. This study aimed to measure the impact of DOACs compared to warfarin on safety and efficacy outcomes in extreme body weight patients. This multi-center, health system, retrospective study examined the outcomes of patients with all body weights and extreme body weights prescribed a DOAC (rivaroxaban, apixaban, dabigatran, edoxaban) or warfarin for atrial fibrillation or venous thromboembolism over a 9-year period. The primary outcome was a composite of thromboembolism, symptomatic recurrent VTE, or severe bleeding; analyzed by pre-determined BMI cutoffs. A total of 19,697 patients were included in the study: 11,604 in the DOAC group and in the 8093 in the warfarin group. 295 patients were underweight and 9108 patients were pre-obese to obese class 3. After adjusting for potential confounders, warfarin patients had higher odds of experiencing the composite outcome compared to DOAC patients (OR 1.337, 95% CI 1.212-1.475). Additionally, obese patients were 24.6% more likely to experience the outcome compared to normal BMI patients. Adjusted modeling showed that warfarin patients experienced higher bleed rates compared to DOAC patients (OR 1.432, 95% CI 1.266-1.620). Obese patients were less likely to be diagnosed with a bleed (OR 0.749, 95% CI 0.658-0.854), and underweight patients were more likely to be diagnosed with a bleed (OR 1.522, 95% CI 1.095-2.115) compared to normal BMI patients. In conclusion, DOACs for atrial fibrillation or VTE in patients with extreme body weights appear safe and effective when compared to warfarin.

Evaluation of a patient specific, targeted-intensity pharmacologic thromboprophylaxis protocol in hospitalized patients with COVID-19.

Patients with COVID-19 are at higher risk of thrombosis due to the inflammatory nature of their disease. A higher-intensity approach to pharmacologic thromboprophylaxis may be warranted. The objective of this retrospective cohort study was to determine if a patient specific, targeted-intensity pharmacologic thromboprophylaxis protocol incorporating severity of illness, weight, and biomarkers decreased incidence of thrombosis in hospitalized patients with COVID-19. Included patients were hospitalized with COVID-19 and received thromboprophylaxis within 48 h of admission. Exclusion criteria included receipt of therapeutic anticoagulation prior to or within 24 h of admission, history of heparin-induced thrombocytopenia, extracorporeal membrane oxygenation, pregnancy, or incarceration. Per-protocol patients received thromboprophylaxis according to institutional protocol involving escalated doses of anticoagulants based upon severity of illness, total body weight, and biomarker thresholds. The primary outcome was thrombosis. Secondary outcomes included major bleeding, mortality, and identification of risk factors for thrombosis. Of 1189 patients screened, 803 were included in the final analysis. The median age was 54 (42-65) and 446 (55.5%) were male. Patients in the per-protocol group experienced significantly fewer thrombotic events (4.4% vs. 10.7%, p = 0.002), less major bleeding (3.1% vs. 9.6%, p < 0.001), and lower mortality (6.3% vs. 11.8%, p = 0.02) when compared to patients treated off-protocol. Significant predictors of thrombosis included mechanical ventilation and male sex. Post-hoc regression analysis identified mechanical ventilation, major bleeding, and D-dimer ≥ 1500 ng/mL FEU as significant predictors of mortality. A targeted pharmacologic thromboprophylaxis protocol incorporating severity of illness, body weight, and biomarkers appears effective and safe for preventing thrombosis in patients with COVID-19.

Ribavirin and cellular ribavirin-triphosphate concentrations in blood and bronchoalveolar lavage fluid in two lung transplant patients with respiratory syncytial virus.

Respiratory syncytial virus (RSV) is responsible for significant morbidity and mortality in the lung transplant population. Oral and aerosolized ribavirin may improve outcomes in lung transplant patients with RSV; however, data relating ribavirin concentrations in plasma and intracellular ribavirin triphosphate (iRTP) concentrations in blood and bronchoalveolar lavage (BAL) fluid cells with efficacy and safety are lacking. We describe ribavirin and iRTP concentrations within various compartments in two adult lung transplant recipients with RSV who were sampled throughout successful treatment courses with oral and inhaled ribavirin. In patient 1, iRTP BAL concentrations decreased by 45% over 3 days after changing inhaled ribavirin to oral (6.32 to 3.43 pmol/106 cells). In patient 2, iRTP BAL concentrations were 103 pmol/106 cells after 5 days of oral followed by 5 days of inhaled ribavirin. Further study is needed to describe ribavirin pharmacokinetics in the respiratory compartment to inform clinical use of ribavirin for respiratory viruses.

Hydroxocobalamin Versus Methylene Blue for Vasoplegic Syndrome in Cardiothoracic Surgery: A Retrospective Cohort.

OBJECTIVE: To compare methylene blue with hydroxocobalamin as a rescue therapy for vasoplegic syndrome. DESIGN: Retrospective cohort. SETTING: Academic medical center. PARTICIPANTS: Patients undergoing cardiothoracic surgery treated for vasoplegic syndrome. INTERVENTIONS: Thirty-five patients were treated with methylene blue (n = 16) or hydroxocobalamin (n = 19). MEASUREMENTS AND MAIN RESULTS: Mean arterial pressure, systemic vascular resistance, and vasopressor exposures were recorded before and after medication administration. Change in time-averaged norepinephrine equivalents in the hour after administration was the primary outcome. The average norepinephrine equivalent observed at baseline in this cohort was 0.347 µg/kg/min. Methylene blue patients had greater Acute Physiological Assessment and Chronic Health Evaluation II scores (29.8 v 22.2; p = 0.01) and trended toward greater European System for Cardiac Operative Risk Evaluation II values (26.8% v 15.1%; p = 0.07). Methylene blue and hydroxocobalamin were associated with increased mean arterial pressure and systemic vascular resistance 1 hour after administration (10.6 mmHg and 192 dyn*sec/cm5; p = 0.01 and p = 0.01, respectively; 11.8 mmHg and 254 dyn*sec/cm5; p = 0.002 and p = 0.015, respectively). Hemodynamic changes were not different between the rescue therapy groups (p = 0.79 and p = 0.53, respectively). No significant differences were observed within the 1-hour change in time-averaged norepinephrine equivalents for either agent or when methylene blue and hydroxocobalamin were compared (0.012 ± 0.218 µg/kg/min v -0.037 ± 0.027 µg/kg/min; p = 0.46, respectively). When compared with baseline time-averaged norepinephrine equivalent (0.326 ± 0.106 µg/kg/min), only hydroxocobalamin was associated with decreased vasopressor requirements at the 1-hour (0.255 ± 0.129 µg/kg/min; p = 0.03) and 4-hour time points (0.247 ± 0.180 µg/kg/min; p = 0.04) post-administration. CONCLUSION: Methylene blue and hydroxocobalamin increased mean arterial pressures and systemic vascular resistance without significantly decreasing time-averaged norepinephrine exposure in the hour after administration.

Oral Vancomycin Prophylaxis as Secondary Prevention Against Clostridioides difficile Infection in the Hematopoietic Stem Cell Transplantation and Hematologic Malignancy Population.

Clostridioides difficile infection (CDI) is a common complication in the hematopoietic stem cell transplantation (HSCT) and hematologic malignancy (HM) population. CDI is associated with increased hospital length of stay, health care and societal costs, morbidity, and mortality. Identifying strategies for secondary prevention of CDI is of extreme importance in the HSCT/HM population. In this study, our primary objective was to evaluate the effectiveness and safety of an oral vancomycin prophylaxis (OVP) protocol for secondary prevention of CDI in a retrospective cohort of adult autologous/allogeneic HSCT recipients and patients with HM who did not undergo HSCT with a first CDI episode treated with concomitant broad-spectrum antibiotics (BSA). Patients were diagnosed and treated for CDI as inpatients and/or outpatients and were divided into 2 groups based on a preprotocol versus postprotocol analysis: the OVP group, comprising patients who received planned monotherapy with oral vancomycin 125 mg every 6 hours for 14 days for a first episode of CDI and subsequently received OVP posttreatment and a no OVP (NOVP) group, comprising patients who received planned monotherapy with oral vancomycin 125 mg every 6 hours for 14 days for a first episode of CDI and subsequently did not receive OVP posttreatment. OVP was defined as vancomycin 125 mg every 12 hours for up to 7 days after BSA discontinuation. The primary endpoint was recurrent CDI (rCDI), defined as symptoms of loose stools/diarrhea with high clinical suspicion for CDI prompting empiric therapy within 60 days of completion of treatment/prophylaxis for the first CDI episode. The incidence of vancomycin-resistant enterococcal (VRE) infection and 60-day mortality were also compared between the 2 groups. Multivariate logistic regression was created from associated variables to identify independent associations with rCDI. A total of 50 patients were included, 21 in the OVP group (42%) and 29 in the NOVP group (58%). The mean patient age was 58 years, and the cohort was 60% male and 86% Caucasian. HSCT was performed in 60% of the patients, and 76% of CDI cases were diagnosed during hospitalization. The rate of rCDI was significantly lower in the OVP group compared with the NOVP group (5% [1 of 21] versus 35% [10 of 29]; P= .016), with no subsequent increase in VRE infection rate (14% [3 of 21] versus 10% [3 of 29]; P = .686). By multivariable logistic regression, rCDI was inversely associated with OVP (odds ratio [OR], .14; 95% confidence interval [CI], .007 to .994; P = .049) and directly associated with outpatient CDI diagnosis (OR, 8.72; 95% CI, 1.816 to 49.158; P = .007). No between-group differences were found in 60-day mortality (10% [2 of 21] for OVP versus 7% [2 of 29] for NOVP; P > 0.999). OVP appears to be safe and effective for secondary prevention of CDI in the HSCT/HM population. Prospective trials are needed to validate the effectiveness of OVP in this vulnerable population to prevent rCDI.

Assessment of Opioid Cross-reactivity and Provider Perceptions in Hospitalized Patients With Reported Opioid Allergies.

Background: The incidence of opioid allergy cross-reactivity in hospitalized patients with historical opioid allergies remains unknown. Objectives: The purpose of this study was to characterize the incidence of newly suspected IgE-mediated reactions (IMRs) based on clinical criteria among patients with a chart-documented opioid allergy and to assess clinician perceptions of opioid allergies. Methods: This retrospective cohort study was conducted in hospitalized adults with a historically documented opioid allergy who received a subsequent opioid. The primary outcome was the incidence of allergic cross-reactivity between clinical and chemical opioid classes in patients with historical IMRs (H-IMRs) identified by clinical criteria, ICD-9 diagnosis codes, or allergic reaction treatment. Secondary outcomes included the incidence of opioid intolerances incorrectly documented as allergies and a survey to clinicians to assess the impact of opiate warnings on prescribing practices. Results: A total of 499 patients with historical opioid allergies were included. H-IMR to an opioid of any class was not significantly associated with IMR cross-reactivity to the same or any other class, with cross-reactivity rates ranging from 0% to 6.7%. Of the historical chart-documented allergies, 249 reactions (50%) were determined to be intolerances. A total of 461 (92.5%) patients successfully tolerated readministration of opioids despite a chart-documented allergy, and 8 (1.6%) patients developed possible IMR (7 pruritus, 1 possible anaphylaxis). Survey results (n = 54) indicated that opiate allergy warnings were neutral or unlikely to change opiate prescribing. Conclusions: The risk of IMRs caused by opioids is low in patients with H-IMRs to opioids. Opioid allergy documentations may propagate alert fatigue and unwarranted prescribing changes.

Comparative evaluation of isavuconazonium sulfate, voriconazole, and posaconazole for the management of invasive fungal infections in an academic medical center.

BACKGROUND: Invasive fungal infections are a major cause of morbidity and mortality. Newer antifungals may provide similar efficacy with improved safety compared to older more established treatments. This study aimed to compare clinically relevant safety and efficacy outcomes in real world patients treated with isavuconazole, voriconazole, or posaconazole. METHODS: This single center retrospective matched cohort study evaluated adults between January 2015 and December 2017. The primary outcome was a composite safety analysis of antifungal related QTc prolongation, elevated liver function tests (> 5 times ULN), or any documented adverse drug event. Key secondary outcomes included: individual safety events, 30-day readmissions, magnitude of drug interactions with immunosuppressive therapy, and overall cost. RESULTS: A total of 100 patients were included: 34 patients in the voriconazole group and 33 patients within each of the isavuconazole and posaconazole groups. The composite safety outcome occurred in 40% of the total cohort and was different between isavuconazole (24.2%), voriconazole (55.9%), and posaconazole (39.4%; p = 0.028). Change in QTc (p < 0.01) and magnitude of immunosuppression dose reduction (p = 0.029) were different between the three groups. No differences in mortality, length of stay, readmission, or infection recurrence were observed between groups (p > 0.05 for all). The overall medication cost, when including therapeutic drug monitoring, was not different between treatments (p = 0.36). CONCLUSIONS: Patients treated with isavuconazole resulted in fewer composite safety outcomes, driven by decreased incidence of QTc prolongation, compared to patients treated with voriconazole or posaconazole. Overall drug cost was not significantly different between the treatment therapy options.

Thiocyanate Accumulation in Critically Ill Patients Receiving Nitroprusside Infusions.

PURPOSE: This study evaluated thiocyanate concentrations and factors associated with thiocyanate accumulation in intensive care unit patients receiving nitroprusside with and without sodium thiosulfate coadministration. MATERIALS AND METHODS: This retrospective study evaluated critically ill adults who received nitroprusside infusions and had at least one thiocyanate concentration. Patients with thiocyanate accumulation (concentrations ≥30 µg/mL) were compared to patients without accumulation. Factors associated with accumulation were determined by Spearman correlation and multivariate regression. RESULTS: Thiocyanate concentrations (n = 192) were obtained from 87 patients. Fourteen of the 87 (16%) patients experienced thiocyanate accumulation with a mean (SD) thiocyanate concentration of 44 ± 11 µg/mL. Patients with accumulation had received greater cumulative nitroprusside doses (28 vs 8.2 mg/kg, P < .01), greater cumulative sodium thiosulfate doses (16.8 vs 10.1 mg/kg, P < .01), and longer infusion durations (10.9 vs 6.0 days, P < .01), compared to patients without accumulation. Sodium thiosulfate coadministration resulted in greater thiocyanate concentrations (22.8 ± 16.7 vs 16.8 ± 14.9 µg/mL, P = .01), despite utilization of lower cumulative nitroprusside doses (10.2 vs 14.6 mg/kg, P = .03). Cumulative nitroprusside dose ( r2 .44, P < .001) and cumulative sodium thiosulfate dose ( r2 .32, P < .001) demonstrated a significant correlation with measured thiocyanate concentrations. Thiocyanate accumulation was independently associated with cumulative nitroprusside dose in mg/kg (regression coefficient 0.75, 95% CI 0.63-0.89; P < .01). No clinically significant adverse effects of cyanide or thiocyanate toxicity were observed. CONCLUSIONS: Cumulative nitroprusside dose was independently associated with thiocyanate accumulation. Despite elevated thiocyanate levels in 16% of patients, there was no clinical evidence of cyanide or thiocyanate toxicity. Routine monitoring of thiocyanate concentrations appears most warranted in patients receiving higher cumulative doses of nitroprusside.

Voriconazole and posaconazole therapeutic drug monitoring: a retrospective study.

BACKGROUND: Therapeutic drug monitoring (TDM) aims to minimize the clinical impact of posaconazole and voriconazole pharmacokinetic variability. However, its benefits on clinical outcomes are still being defined. Additionally, TDM data are limited for posaconazole IV and delayed-release tablet formulations among specific patient populations, including critically ill. The aim of this study was to determine the percentage of therapeutic posaconazole and voriconazole drug levels across all formulations in a real-world clinical setting and elucidate factors affecting attainment of target concentrations. METHODS: This study was a retrospective cohort study conducted at the University of Colorado Hospital between September 2006 and June 2015 that evaluated patients who received posaconazole or voriconazole TDM as part of routine care. RESULTS: Voriconazole (n = 250) and posaconazole (n = 100) levels were analyzed from 151 patients. Of these, 54% of voriconazole and 69% of posaconazole levels were therapeutic. For posaconazole, 14/38 (37%), 28/29 (97%) and 27/33 (82%) levels were therapeutic for the oral suspension, IV, and delayed-release tablet, respectively. Intravenous and delayed-release tablet posaconazole were 20 fold (p < 0.01) and sevenfold (p = 0.002) more likely than the oral suspension to achieve a therapeutic level. Subsequent levels were more likely to be therapeutic after dose adjustments (OR 3.31; 95% CI 1.3-8.6; p = 0.02), regardless of timing of initial non-therapeutic level. In a multivariable logistic regression analysis, no characteristics were independently predictive of therapeutic voriconazole levels and only absence of H2RA/PPI use was independently predictive of therapeutic posaconazole levels. There was no correlation between survival and therapeutic drug levels for either voriconazole (p = 0.67) or posaconazole (p = 0.50). CONCLUSIONS: A high percentage of drug levels did not achieve TDM targets for voriconazole and posaconazole oral suspension, supporting the need for routine TDM for those formulations. The utility of TDM for the IV and delayed-release tablet formulations of posaconazole is less apparent.

Pharmacokinetic and Pharmacodynamic Evaluation of a Weight-Based Dosing Regimen of Cefoxitin for Perioperative Surgical Prophylaxis in Obese and Morbidly Obese Patients.

The objective of this study was to determine the pharmacokinetics and pharmacodynamics (PK/PD) of a weight-based cefoxitin dosing regimen for surgical prophylaxis in obese patients. Patients received a single dose of cefoxitin at 40 mg/kg based on total body weight. Cefoxitin samples were obtained over 3 h from serum and adipose tissue, and concentrations were determined by validated high-performance liquid chromatography. Noncompartmental pharmacokinetic analysis was performed, followed by Monte Carlo simulations to estimate probability of target attainment (PTA) for Staphylococcus aureus, Escherichia coli, and Bacteroides fragilis over 4-h periods postdose. Thirty patients undergoing bariatric procedures were enrolled. The body mass index (mean ± standard deviation [SD])was 45.9 ± 8.0 kg/m(2) (range, 35.0 to 76.7 kg/m(2)); the median cefoxitin dose was 5 g (range, 4.0 to 7.5 g). The mean maximum concentrations were 216.15 ± 41.80 µg/ml in serum and 12.62 ± 5.89 in tissue; the mean tissue/serum ratio was 8% ± 3%. In serum, weight-based regimens achieved ≥90% PTA (goal time during which free [unbound] drug concentrations exceed pathogen MICs [fT>MIC] of 100%) for E. coli and S. aureus over 2 h and for B. fragilis over 1 h; in tissue this regimen failed to achieve goal PTA at any time point. The 40-mg/kg regimens achieved higher PTAs over longer periods in both serum and tissue than did the standard 2-g doses. However, although weight-based cefoxitin regimens were better than fixed doses, achievement of desired pharmacodynamic targets was suboptimal in both serum and tissue. Alternative dosing regimens and agents should be explored in order to achieve more favorable antibiotic performance during surgical prophylaxis in obese patients.

Evaluation of Early Dexmedetomidine Addition to the Standard of Care for Severe Alcohol Withdrawal in the ICU: A Retrospective Controlled Cohort Study.

PURPOSE: This study evaluated the impact of dexmedetomidine (DEX) administration on benzodiazepine (BZD) requirements in intensive care unit (ICU) patients experiencing alcohol withdrawal syndrome (AWS). METHODS: This trial included adults admitted to the ICU for >24 hours for AWS. Early DEX was defined as receiving DEX within 60 hours of hospital admission. The primary outcome was 12-hour BZD requirement from the inflection point or DEX initiation. Secondary outcomes included 24-hour BZD requirements, symptom control, ICU and hospital length of stay, and incidence and duration of mechanical ventilation. Safety outcomes included incidence of bradycardia and hypotension. RESULTS: Twenty patients receiving DEX were matched to 22 control patients. The mean 12-hour change in BZD requirement was significantly different for DEX versus control (-20 vs -8.3 mg, P = .0455) with a trend toward significance at 24 hours (-29.6 vs -11 mg, P = .06). No significant differences were noted in other secondary outcomes. Patients receiving DEX experienced significantly more bradycardia than controls (35% vs 0%, P < .01) but not hypotension. CONCLUSIONS: This study suggests DEX is associated with a reduction in BZD requirement when utilized as adjunctive therapy for AWS. A larger prospective trial is needed to evaluate the clinical impact of DEX for AWS.

Evaluation of Sulfobutylether-ß-Cyclodextrin Exposure in a Critically Ill Patient Receiving Intravenous Posaconazole While Undergoing Continuous Venovenous Hemofiltration.

We present a 31-year-old female who had undergone an allogeneic bone marrow transplantation and who was started on intravenous posaconazole for pulmonary mycosis while undergoing continuous venovenous hemofiltration (CVVH). We performed steady-state pharmacokinetic evaluations for both posaconazole and sulfobutylether-ß-cyclodextrin (SBECD). SBECD was effectively removed by CVVH, with observed exposure similar to that for patients with moderate renal impairment. Intravenous posaconazole at standard doses may be utilized in critically ill patients undergoing CVVH without significant risk of SBECD accumulation.

A randomized, double-blind pilot study of dexmedetomidine versus midazolam for intensive care unit sedation: patient recall of their experiences and short-term psychological outcomes.

INTRODUCTION: Sedation with dexmedetomidine may facilitate ventilator liberation and limit the occurrence of delirium. No trial has assessed patient recall or the development of psychological outcomes after dexmedetomidine sedation. This pilot study evaluated whether transitioning benzodiazepine sedation to dexmedetomidine alters patient recall and the incidence of anxiety, depression, or acute stress disorder (ASD). METHODS: This investigation was a randomized, double-blind, single-center study. Existing continuous benzodiazepine sedation was converted to dexmedetomidine or midazolam when patients qualified for daily awakenings. Sedation was titrated to achieve Riker sedation agitation scores of 3 to 4. The intensive care unit (ICU) Stressful Experiences Questionnaire, hospital anxiety and depression scale, and the impact of event scale-revised were administered before hospital discharge to assess recall, anxiety, depression, and manifestations of ASD. RESULTS: A total of 11 patients received dexmedetomidine, and 12 patients received midazolam. Median dosing was 0.61 µg/kg/h for 3.5 days for dexmedetomidine and 3.7 mg/h for 3 days for midazolam. Attainment of goal sedation and analgesia was similar; however, more dexmedetomidine patients experienced agitation and pain. The median duration of mechanical ventilation from study drug initiation to extubation was 3.4 days in dexmedetomidine patients and 2.9 days in midazolam patients. Dexmedetomidine patients remembered 18.5 experiences compared with 8.5 in midazolam patients (P = .015). Rates of anxiety and depression were similar. In all, 5 (62.5%) dexmedetomidine patients and 1 (12.5%) midazolam patient manifested ASD (P = .063), and 1 dexmedetomidine patient and 5 midazolam patients developed new-onset delirium (P = .07). Hypotension occurred in 10 (90.9%) dexmedotomidine patients and 6 (50%) midazolam patients (P = .069). CONCLUSIONS: Transitioning benzodiazepine sedation to dexmedetomidine when patients qualify for daily awakenings may reduce the development of delirium and facilitate remembrance of ICU experiences but may lead to manifestations of ASD. Monitoring hypotension is required for both the sedatives. Additional comparative studies focusing on the long-term impact of ICU recall and psychological outcomes are needed.

A randomized, double-blind, placebo-controlled dose range study of dexmedetomidine as adjunctive therapy for alcohol withdrawal.

OBJECTIVES: To evaluate dexmedetomidine as adjunctive therapy to lorazepam for severe alcohol withdrawal. DESIGN: Prospective, randomized, double-blind, placebo-controlled trial. SETTING: Single center; medical ICU. PATIENTS: Twenty-four adult patients with a Clinical Institute Withdrawal Assessment score greater than or equal to 15 despite greater than or equal to 16 mg of lorazepam over a 4-hour period. INTERVENTIONS: Patients received a symptom-triggered Clinical Institute Withdrawal Assessment protocol with lorazepam and were randomized to dexmedetomidine 1.2 µg/kg/hr (high dose), 0.4 µg/kg/hr (low dose), or placebo as adjunctive therapy for up to 5 days or resolution of withdrawal symptoms. MEASUREMENT AND MAIN RESULTS: High-dose and low-dose groups were combined as a single dexmedetomidine group for primary analysis with secondary analysis exploring a dose-response relationship. The difference in 24-hour lorazepam requirements after versus before study drug was greater in the dexmedetomidine group compared with the placebo group (-56 mg vs -8 mg, p = 0.037). Median differences were similar for high dose and low dose. The 7-day cumulative lorazepam requirements were not statistically different between dexmedetomidine and placebo (159 mg vs 181 mg). Clinical Institute Withdrawal Assessment or Riker sedation-agitation scale scores representing severe agitation (13% vs 25%) or moderate agitation (27% vs 22%) within 24 hours of initiating study drug were similar for dexmedetomidine and placebo groups, respectively. Bradycardia occurred more frequently in the dexmedetomidine group versus placebo group (25% vs 0%, p = not significant), with the majority of bradycardia occurring in the high-dose group (37.5%). Study drug rate adjustments occurred more often in the dexmedetomidine group compared with the placebo group (50% vs 0%, p = 0.02). Neither endotracheal intubation nor seizure occurred in any group while on study drug. CONCLUSIONS: Adjunctive dexmedetomidine for severe alcohol withdrawal maintains symptom control and reduces lorazepam exposure in the short term, but not long term, when using a symptom-triggered protocol. Monitoring for bradycardia is needed with dexmedetomidine but the occurrence may be lessened with low dose. Further study is needed to evaluate the clinical impact of dexmedetomidine.

Early administration of infliximab for severe ipilimumab-related diarrhea in a critically ill patient.

OBJECTIVE: To report a case of ipilimumab-associated life-threatening diarrhea responding quickly to a single dose of infliximab. CASE SUMMARY: A 67-year-old man presented 3 weeks after his second dose of ipilimumab with severe diarrhea, acute kidney injury, and hypotension. After 2 days of high-dose corticosteroids and supportive care, he continued to have 2.8 L of stool output per day (grade 4 National Cancer Institute Common Terminology Criteria for Adverse Events). The patient was transferred to the medical intensive care unit requiring endotracheal intubation because of concerns of worsening mental status, metabolic acidosis, and increased work of breathing, with a serum bicarbonate concentration of <5 mmol/L. Despite aggressive fluid resuscitation and a sodium bicarbonate infusion, he remained hypotensive and hyponatremic with persistent premature ventricular contractions. On the evening of day 3, infliximab (5 mg/kg) was given, resulting in a rapid decrease in diarrhea. After 48 hours, the acidosis was corrected and electrolytes, renal function, and fluid status were improving. At discharge, diarrhea, acute kidney injury, and acidosis had resolved, and he was discharged on a slow steroid taper. DISCUSSION: Autoimmune colitis is a described immune-related adverse event of ipilimumab. Prompt recognition, initiation of steroids, and supportive therapy are key to the management of diarrhea. Infliximab should be considered early in steroid-nonresponsive or life-threatening diarrhea. CONCLUSION: Infliximab is a life-saving intervention in patients with ipilimumab-induced diarrhea.

The Integration of Physical Therapists and Occupational Therapists into Burn Wound Care Increases Therapist Productivity, Job Satisfaction, and Multidisciplinary Collaboration.

When attempting to deliver specialized rehabilitation therapy interventions, physical therapists (PTs) and occupational therapists (OTs) must account for dynamic and logistical patient factors such as daily wound care, pain, difficulty progressing range of motion with dressings donned, and ongoing surgical interventions. Additionally, they must attain institution-specific productivity standards. Given burn patients often require considerable multidisciplinary interventions, efficiently planning and delivering rehabilitation therapy interventions within productivity expectations may prove difficult. The purpose of this study was to assess the feasibility of integrating rehabilitation therapists, PTs and OTs, into daily burn wound care by investigating therapist productivity and multidisciplinary perceptions of this practice change. The quality improvement project involved 6 rehabilitation therapists (3 PTs and 3 OTs) practicing exclusively in the burn unit within an American Burn Association (ABA)-verified burn center at an urban, tertiary care academic medical center. One rehabilitation therapist was responsible for providing interventions within the burn wound care team 5 days a week. General duties included wound assessment, functional wound dressings, and skilled therapeutic interventions such as manual therapy, therapeutic exercise, and compression interventions. The primary outcome was changes in group productivity and individual therapist productivity, as measured by total billed Current Procedural Terminology (CPT) codes per hour worked, which were tracked 22 weeks preimplementation and 28 weeks postimplementation. Program feasibility and general perceptions were assessed by a qualitative questionnaire. For both the entire group of therapists and each individual rehabilitation therapist, billed CPT codes per hour increased postimplementation, 1.81 vs 1.54 (P = .005) and a matched increase of 0.27/h (P = .003). Of the 23 survey respondents, 96% had a favorable impression of the program and reported it eased staffing demands. All respondents reported improved unit workflow and multidisciplinary communication. The majority of multidisciplinary burn team members actively supported the pilot program and commented on improvements in patient care. Full-time rehabilitation therapy participation in wound care increases therapist productivity and job satisfaction. Future efforts, however, should focus on measuring specific patient outcomes and costs as a result of therapist integration into daily wound care practice.