Comparison of Doxycycline or Minocycline to Sulfamethoxazole-Trimethoprim for Treatment of Stenotrophomonas maltophilia Pneumonia.

BACKGROUND: Stenotrophomonas maltophilia is a multidrug-resistant organism with limited antibiotic treatment options. Minocycline and doxycycline may be appropriate, but clinical data are limited. OBJECTIVE: To compare tetracyclines (minocycline and doxycycline [TCN]) with standard of care, sulfamethoxazole-trimethoprim (TMP-SMZ), in S. maltophilia pneumonia treatment. METHODS: This retrospective, 2-center study evaluated patients treated for S. maltophilia pneumonia with TCN or TMP-SMZ for clinical success, defined as resolution of leukocytosis, fever, and tachypnea. Patients were classified as treatment with TCN or TMP-SMZ based on definitive agent used for ≥50% of the treatment course and ≥4 days. Inclusion criteria were age ≥18 years, S. maltophilia confirmed on respiratory culture from January 2013 to November 2020, and appropriate definitive antibiotic dosing. Pregnancy, incarceration, S. maltophilia-resistant or intermediate to definitive therapy, and combination therapy for treatment of S. maltophilia pneumonia were exclusion criteria. Secondary outcomes were microbiologic success and recurrence or reinfection within 30 days requiring treatment. RESULTS: A total of 80 patients were included (21 TCN [15 minocycline, 6 doxycycline], 59 TMP-SMZ). There was no difference in clinical success (28.6% vs 25.4%; P = 0.994), microbiologic success (n = 28, 55.6% vs 66.4%; P = 0.677), or recurrence or reinfection (n = 24, 66.7% vs 26.7%; P = 0.092) between TCN and TMP-SMZ, respectively. CONCLUSION AND RELEVANCE: Clinical and microbiologic success rates were similar in patients treated with TCN compared with TMP-SMZ for S. maltophilia pneumonia. These data suggest minocycline and doxycycline may be options to treat S. maltophilia pneumonia, but conclusive clinical data continue to be lacking.

Pharmacokinetics of Levetiracetam Seizure Prophylaxis in Severe Traumatic Brain Injury.

BACKGROUND: Drug pharmacokinetics (PK) are altered in neurocritically ill patients, and optimal levetiracetam dosing for seizure prophylaxis is unknown. OBJECTIVE: This study evaluates levetiracetam PK in critically ill patients with severe traumatic brain injury (sTBI) receiving intravenous levetiracetam 1000 mg every 8 (LEV8) to 12 (LEV12) hours for seizure prophylaxis. METHODS: This prospective, open-label study was conducted at a level 1 trauma, academic, quaternary care center. Patients with sTBI receiving seizure prophylaxis with LEV8 or LEV12 were eligible for enrollment. Five sequential, steady-state, postdose serum levetiracetam concentrations were obtained. Non-compartmental analysis (NCA) and compartmental approaches were employed for estimating pharmacokinetic parameters and projecting steady-state trough concentrations. Pharmacokinetic parameters were compared between LEV8 and LEV12 patients. Monte Carlo simulations (MCS) were performed to determine probability of target trough attainment (PTA) of 6 to 20 mg/L. A secondary analysis evaluated PTA for weight-tiered levetiracetam dosing. RESULTS: Ten male patients (5 LEV8; 5 LEV12) were included. The NCA-based systemic clearance and elimination half-life were 5.3 ± 1.2 L/h and 4.8 ± 0.64 hours. A one-compartment model provided a higher steady-state trough concentration for the LEV8 group compared with the LEV12 group (13.7 ± 4.3 mg/L vs 6.3 ± 1.7 mg/L; P = 0.008). Monte Carlo simulations predicted regimens of 500 mg every 6 hours, 1000 mg every 8 hours, and 2000 mg every 12 hours achieved therapeutic target attainment. Weight-tiered dosing regimens achieved therapeutic target attainment using a 75 kg breakpoint. CONCLUSION AND RELEVANCE: Neurocritically ill patients exhibit rapid levetiracetam clearance resulting in a short elimination half-life. Findings of this study suggest regimens of levetiracetam 500 mg every 6 hours, 1000 mg every 8 hours, or 2000 mg every 12 hours may be required for optimal therapeutic target attainment. Patient weight of 75 kg may serve as a breakpoint for weight-guided dosing to optimize levetiracetam therapeutic target attainment for seizure prophylaxis.

Acute Pain Management in Traumatically Injured Patients With Outpatient Buprenorphine Therapy.

INTRODUCTION: Acute pain management is challenging in trauma patients undergoing outpatient buprenorphine therapy at the time of injury due to the high binding affinity of this partial agonist. The purpose of this study was to evaluate acute pain management in admitted trauma patients with discontinued versus continued outpatient buprenorphine therapy. MATERIALS AND METHODS: This retrospective study included adult trauma patients admitted to a level-1 trauma center between January 2017 and August 2020 who were receiving buprenorphine prior to admission. Groups were defined as buprenorphine discontinued (BD) or continued (BC) during hospitalization. The primary outcome compared median daily morphine milligram equivalents between groups. Secondary outcomes utilized patient-reported numeric rating scale (NRS) scores to compare incidences of no pain (NRS 0), mild (NRS 1-3), moderate (NRS 4-6), and severe (NRS 7-10) pain. RESULTS: A total of 57 patients were included (BD 37 [64.9%] and BC 20 [35.1%]). The median (interquartile range) outpatient daily buprenorphine dose was similar between groups (8 [8-16] mg versus 16 [8-16], P = 0.25). Median daily morphine milligram equivalents was significantly higher during admission in the BD group (103.7 [80.7-166] versus 67 [30.8-97.4], P = 0.002). Incidence of no pain (7.1% versus 5.7%, P = 0.283), mild (5.5% versus 4.3%, P = 0.295), moderate (20.2%, 19.8%, P = 0.855), or severe (67.2% versus 70.2%, P = 0.185) pain was similar between BD and BC groups, respectively. CONCLUSIONS: Continuation of outpatient buprenorphine therapy in acute trauma patients is associated with decreased daily opioid requirements and similar analgesic efficacy compared to patients with BD. Based on our findings, trauma patients receiving outpatient buprenorphine and not requiring ventilator support may benefit from buprenorphine continuation within 48 h of initial presentation.

Sugammadex Efficacy and Dosing for Rocuronium Reversal Outside of Perioperative Settings.

Background: Sugammadex is approved for postoperative recovery from rocuronium neuromuscular blockade with train-of-four (TOF) guided dosing. Data for non-perioperative sugammadex efficacy and dosing are limited when TOF is not available and reversal is not immediate. Objective: This study evaluated the efficacy, safety, and dose of sugammadex when administered in the emergency department (ED) or intensive care unit (ICU) for delayed rocuronium reversal when TOF guidance was not consistently available. Methods: This single-center, retrospective cohort study included patients over a 6-year period who received sugammadex in the ED or ICU at least 30 minutes after rocuronium administration for rapid sequence intubation (RSI). Patients who received sugammadex for intra-operative neuromuscular blockade reversal were excluded. Efficacy was defined as successful reversal documented in progress notes, TOF assessment, or improvement in Glasgow Coma Scale (GCS). Dose was evaluated in patients with successful reversal by correlating sugammadex and rocuronium dose with reversal time after paralysis. Results: Thirty-four patients were included with 19 (55.9%) patients receiving sugammadex in the ED. Sugammadex indication was acute neurologic assessment in 31 (91.1%) patients. Twenty-nine patients (85.2%) had successful reversal documented. The remaining 5 patients had fatal neurologic injuries with GCS 3 limiting non-TOF efficacy assessment. The median (IQR) sugammadex dose was 3.4 (2.5-4.1) mg/kg administered 89 (56.3-158) minutes after rocuronium. No correlation was identified between sugammadex dose, rocuronium dose, and administration time. No adverse events were noted. Conclusion: This pilot investigation demonstrated safe and effective rocuronium reversal with sugammadex 3 to 4 mg/kg administered in the non-operative setting 1 to 2 hours after RSI. Larger, prospective studies are necessary to determine the safety in patients outside of the operating room when TOF is not available.

Case Report: Extended Duration Andexanet Alfa Infusion in a Surgical Trauma Patient.

Background: Andexanet alfa (andexanet) is the only FDA-approved medication for reversal of apixaban and rivaroxaban anticoagulation for life-threatening or uncontrolled bleeding. Infusion modifications may be required in surgical patients undergoing prolonged operative intervention but have not previously been described. Case Report: A 78-year-old woman on rivaroxaban for atrial fibrillation was admitted to the trauma service for a mechanical fall, sustaining a T4 burst fracture with severe canal stenosis and spinal cord edema resulting in loss of strength and sensation in her legs. Clinically relevant rivaroxaban activity was verified with an elevated low molecular weight heparin anti-factor Xa assay, and laboratory confirmed coagulopathy was demonstrated by a prolonged prothrombin time, thromboelastography (TEG) R-time, and activated clotting time (ACT). The patient required urgent surgical intervention for spinal fixation. Given the expected prolonged duration of the procedure, standard dose andexanet was initiated with a prolonged infusion at half the standard rate during the operation. The procedure was successful and intraoperative TEGs demonstrated normalization of R-time and ACT throughout the procedure. The patient did not experience any complications postoperatively and successfully discharged to inpatient rehabilitation. Conclusion: Modifications to the andexanet infusion may be required in surgical patients requiring rivaroxaban reversal for a prolonged procedure. Further data are needed to determine the optimal approach to infusion modification.

Applying Cefepime Population Pharmacokinetics to Critically Ill Patients Receiving Continuous Renal Replacement Therapy.

Patients admitted to the intensive care unit (ICU) may need continuous renal replacement therapy (CRRT) due to acute kidney injury or worsening of underlying chronic kidney disease. This will affect their antimicrobial exposure and may have a significant impact on the treatment. We aim to develop a cefepime pharmacokinetic (PK) model in CRRT ICU patients and generate the posterior predictions for a group and assess their therapy outcomes. Adult patients, who were admitted to the ICU, received cefepime, and had its concentration measured while on CRRT were included from three different data sets. In two data sets, samples were collected from the predialyzer, postdialyzer ports, and effluent fluid at different times within the same dosing interval. The third data set had only cefepime plasma concentration measured as part of clinical service. Patients' demographics, cefepime regimens and concentration, CRRT parameters, and therapy outcomes were recorded. NPAG was used for population PK and posterior predictions. A total of 125 patients were included. Cefepime was described by a five-compartment model, and the CRRT flow rates described the rates of cefepime transfer between compartments. The posterior predictions were generated for the third data set and the median (range) fT>MIC was 100% (27%-100%) and fT>4×MIC was 64% (0%-100%). The mortality rate was 53%. There was no difference in target attainment in terms of clinical cure and 30-day mortality. This model can be used as a precision dosing tool in CRRT patients. Future studies may address other PK/PD targets in a larger population.

Impact of a Multimodal Analgesia Protocol on Inpatient and Outpatient Opioid Use in Acute Trauma.

BACKGROUND: Multimodal analgesia protocols have been implemented after elective surgery to reduce opioid use, however there is limited data on utility after polytrauma. Therefore, we investigated the impact of a multimodal analgesia protocol on inpatient and post-discharge outpatient opioid use after polytrauma. METHODS: A retrospective review of patients admitted to a Level I trauma center between September 2017-February 2018 (prior to multimodal protocol; "pre-cohort") and October 2018-April 2019 (after multimodal protocol; "post-cohort") was performed. An outpatient controlled substance registry was utilized to capture morphine milligram equivalents (MME) and gabapentin dispensed in the 6 mo after injury. RESULTS: 620 patients were included (295 pre-cohort, 325 post-cohort). Total inpatient MME decreased from 177.5 mg-130 mg (P= 0.01) between the cohorts. Daily inpatient MME decreased from 70.8 mg-44.7 mg (P< 0.01). Intravenous hydromorphone decreased from 2 mg in the pre-cohort to 1 mg in the post-cohort (P= 0.02). Inpatient oxycodone decreased from 45 mg-30 mg (P= 0.01). Concurrently, gabapentin increased from 0 mg-400 mg in the post-cohort (P< 0.01). Patients in the post-cohort were prescribed fewer MMEs than the pre-cohort at discharge (P< 0.05). However, the number of patients prescribed gabapentin increased from 6.1%-16% (P< 0.01). CONCLUSION: Implementation of an updated multimodal analgesia protocol decreased total MME, daily MME, hydromorphone, and oxycodone consumed while increasing gabapentin use. This suggests that while reducing opioid usage in-hospital is critical to reducing outpatient usage, multimodal pain protocols may lead to an increase in gabapentin prescriptions and utilization after discharge.

Cefepime Population Pharmacokinetics and Target Attainment in Critically Ill Patients on Continuous Renal Replacement Therapy.

Sepsis causes half of acute kidney injuries in the intensive care unit (ICU). ICU patients may need continuous renal replacement therapy (CRRT), which will affect their antimicrobial exposure. We aimed to build a cefepime population pharmacokinetic (PK) model in CRRT ICU patients and perform simulations to assess target attainment. Patients who were ≥18 years old, were admitted to the ICU, and received cefepime 2 g every 8 h as a 4-h infusion while on CRRT were enrolled prospectively. Samples were collected from the predialyzer ports, postdialyzer ports, and effluent fluid at 1, 2, 3, 4, and 8 h after the first dose and at steady state. Age, sex, weight, urine output, and CRRT parameters were recorded. Pmetrics was used for population PK and simulations. The target exposure was 100% of the dosing interval during which the free beta-lactam concentration is above the MIC (fT>MIC). Ten patients were included; their mean age was 53 years, and mean weight was 119 kg. Seventy percent were males. Cefepime was described by a five-compartment model. The downtime was applied to the CRRT flow rates, which were used to describe the rates of transfer between the compartments. At MICs of ≤8 mg/liter, intermittent infusion of 2 g cefepime every 8 h achieved good target attainment both early in therapy and at steady state. Only extended- and continuous-infusion regimens achieved good target attainment at MICs of 16 mg/liter. In conclusion, 2 g cefepime infused over 30 min followed by extended infusion of 2 g every 8 h achieved good target attainment at MICs of ≤16 mg/liter with different CRRT flow rates and may be considered in resistant bacterial infections.

Retrospective Evaluation of Venous Thromboembolism Prophylaxis in Elderly, High-Risk Trauma Patients.

BACKGROUND: Venous thromboembolism (VTE) risk increases with age. Scarce data exist for patients age ≥65 y. This study evaluated VTE incidence in elderly, high-risk trauma patients receiving unfractionated heparin (UFH) or enoxaparin chemoprophylaxis. MATERIALS AND METHODS: This retrospective, single-center, cohort study included trauma patients age ≥ 65 y with risk assessment profile (RAP) ≥ 5 who received UFH or enoxaparin chemoprophylaxis. The primary outcome was VTE incidence requiring therapeutic anticoagulation. An age-modified RAP (RAP-AM) was calculated as RAP without age distribution points. Logistic regression analyses were performed to identify independent predictors for VTE development and chemoprophylactic agent selection. Bleeding incidence compared packed red blood cells utilized. RESULTS: A total of 1090 patients were included (UFH, n = 655; enoxaparin, n = 435). VTE occurred in 39 (3.6%) patients with no difference between groups in proximal deep vein thrombosis (2.1% versus 3.0%, P = 0.52) or pulmonary embolism (1.2% versus 1.4%, P = 0.96). Weight ≥125 kg (OR 4.12, 95% CI 1.06-16.11) and RAP-AM ≥ 5 (OR 6.52, 95% CI 2.65-16.03) were independently associated with VTE development. Increasing age (OR 1.04, 95% CI 1.03-1.06), initiation ≤ 24 h (OR 2.17, 95% CI 1.66-2.84) and creatinine clearance ≤ 30 mL/min (OR 1.61, 95% CI 1.17-2.21) were independent predictors of receiving UFH whereas increasing ISS (OR 0.97, 95% CI 0.95-0.99) was associated with receiving enoxaparin. CONCLUSIONS: VTE incidence may be similar for high-risk, elderly trauma patients receiving UFH and enoxaparin chemoprophylaxis. Further research is necessary to determine noninferiority of UFH to enoxaparin in this patient population.

Pharmacokinetics and Pharmacodynamics of Extended-Infusion Cefepime in Critically Ill Patients Receiving Continuous Renal Replacement Therapy: A Prospective, Open-Label Study.

STUDY OBJECTIVE: To evaluate extended-infusion (EI) cefepime pharmacokinetics (PK) and pharmacodynamic target attainment in critically ill patients receiving continuous venovenous hemofiltration (CVVH) or continuous venovenous hemodialysis (CVVHD). DESIGN: Prospective, open-label, PK study. SETTING: Intensive care units at a large, academic, tertiary-care medical center. PATIENTS: Ten critically ill adults who were receiving cefepime 2 g intravenously every 8 hours as a 4-hour infusion while receiving CVVH (eight patients) or CVVHD (two patients). INTERVENTION: Two sets of five serum cefepime concentrations were collected for each patient to assess pharmacokinetics before and during presumed steady state. Concurrent serum and CRRT effluent samples were collected at hours 1, 2, 3, 4, and 8 after the first cefepime dose and after either the fourth, fifth, or sixth (steady-state) cefepime doses. MEASUREMENTS AND MAIN RESULTS: Reversed-phase high-performance liquid chromatography was used to determine free cefepime concentrations. PK analyses included CRRT clearance, half-life, and sieving coefficient or saturation coefficient. Cefepime peak (4 hrs) concentrations, trough (8 hrs) concentrations (Cmin ), and minimum inhibitory concentration breakpoint of 8 µg/ml for the pathogen (MIC8 ) were used to evaluate attainment of pharmacodynamic targets: 100% of the dosing interval that free drug remains above MIC8 (100% fT > MIC8 ), 100% fT > 4 × MIC8 (optimal), percentage of time fT > 4 × MIC8 (%fT > 4 × MIC8 ) at steady state, and ratio of Cmin to MIC8 (fCmin /MIC8 ). Total CRRT effluent flow rate was a mean ± SD of 30.1 ± 5.4 ml/kg/hr, CRRT clearance was 39.6 ± 9.9 ml/min, and half-life was 5.3 ± 1.7 hours. Sieving coefficient or saturation coefficient were 0.83 ± 0.13 and 0.69 ± 0.22, respectively. First and steady-state dose Cmin were 23.4 ± 10.1 µg/ml and 45.2 ± 14.6 µg/ml, respectively. All patients achieved 100% fT > MIC8 on first and steady-state doses. First and steady-state dose 100% fT > 4 × MIC8 were achieved in 22% (2/9 patients) and 87.5% (7/8 patients) of patients, respectively. The mean %fT > 4 × MIC8 at steady state was 97.5%. The fCmin /MIC8 was 2.92 ± 1.26 for the first dose and 5.65 ± 1.83 at steady state. CONCLUSION: Extended-infusion cefepime dosing in critically ill patients receiving CRRT successfully attained 100% fT > MIC8 in all patients and an appropriate fCmin /MIC8 for both first and steady-state doses. All but one patient achieved 100% fT > 4 × MIC8 at steady state. No significant differences were observed in PK properties between first and steady-state doses among or between patients. It may be reasonable to initiate an empiric or definitive regimen of EI cefepime in critically ill patients receiving concurrent CRRT who are at risk for resistant organisms. Further research is needed to identify the optimal dosing regimen of EI cefepime in this patient population.