High-dose Continuous Infusion Research Articles

Ampicillin-Sulbactam for Carbapenem-Susceptible Acinetobacter baumannii Pneumonia: A Case for High-Dose, Continuous Infusion Dosing Strategy in the Trauma ICU.

Background: The optimal ampicillin-sulbactam dosing regimen for carbapenem-susceptible Acinetobacter baumannii isolates in critically ill trauma patients has not been clearly defined. One strategy to provide the adequate sulbactam dose includes high-dose continuous infusion. Case(s) Description: We present three cases of critically ill trauma patients with augmented renal clearance treated with high-dose ampicillin-sulbactam through an intravenous continuous infusion for ventilator-associated pneumonia. All A. baumannii isolates were susceptible to sulbactam with low minimum inhibitory concentrations. All achieved clinical cure at the end of therapy and no recurrent pneumonia was noted. No clinically substantial adverse effect attributable to ampicillin-sulbactam therapy occurred. Discussion: There is limited evidence to endorse high-dose, continuous infusion ampicillin-sulbactam for treatment of infections caused by carbapenem-susceptible A. baumannii. This report presents three critically ill trauma patients with augmented renal clearance that achieved positive clinical outcomes with higher doses of ampicillin-sulbactam administered through a continuous infusion.

Real-world comparison of low- versus high-dose continuous 5FU infusion in patients receiving triplet chemotherapy plus bevacizumab for newly diagnosed metastatic colorectal cancer (mCRC).

62 Background: Several randomized trials demonstrated an overall survival (OS) benefit to triplet chemotherapy (5-FU, oxaliplatin, and irinotecan) plus bevacizumab compared to doublet chemotherapy plus bevacizumab in patients with newly diagnosed mCRC, though with higher rates of neutropenic fever and diarrhea. These trials used high-dose continuous infusion 5-FU (3,200 mg/m2/48 hours), but national guidelines suggest low-dose continuous infusion 5-FU (2,400mg/m2/48 hours) due to lower tolerance in U.S. patients. We performed a retrospective cohort study in a U.S. population to compare the effectiveness of low- vs high-dose continuous infusion 5FU in patients undergoing triplet chemotherapy plus bevacizumab for newly diagnosed mCRC. Methods: We used the nationwide Flatiron Health electronic health record-derived database, comprising de-identified patient-level structured and unstructured data curated via technology-enabled abstraction from ~280 cancer clinics. Patients with newly diagnosed mCRC who initiated triplet chemotherapy plus bevacizumab between 10/23/14 and 10/31/22 with non-missing height, weight, and dosing data were included. 5FU infusion doses of 2,000 – 2,799 mg/m2 were categorized as low-dose while those >/= 2,800 mg/m2 were categorized as high-dose. OS from first-line treatment initiation was assessed by dosing group using the Kaplan Meier method with log-rank testing. Multivariable analysis with adjustment for pre-specified variables with imbalance (defined by standardized difference < - 0.10 or > 0.10) was performed using multivariable Cox proportional hazards modeling. Missing data were imputed using multiple imputation with chained equations. Results: Among 320 patients included, 244 received low-dose and 76 patients received high-dose continuous infusion 5FU. Imbalance between low- and high-dose groups was observed in the use of 5FU bolus (23% vs 3%), year of metastatic diagnosis 2018 - 2022 (80% vs 55%), mean irinotecan dose (156.4 vs 160.5 mg/m2), left-sided primary (73% vs 64%), MMR deficiency (3% vs 6%) and mean CEA (478 vs 691 µg/L). In univariate analysis, median OS was 33 months (95% CI 26 – 39) in the low-dose group compared to 34 months (95% CI 24 – 48) in the high-dose group (HR 1.16; 95% CI 0.79 – 1.69; p = 0.44). After adjusting for imbalanced covariates, there was no difference in hazard of death between low- and high-dose groups (HR 0.99; 95% CI 0.64 – 1.53; p = 0.97). Conclusions: In this real-world, U.S. population with newly diagnosed mCRC receiving triplet chemotherapy plus bevacizumab, there was no association with survival between low- vs high-dose continuous infusion 5FU. This supports current guidelines recommending low-dose continuous infusion 5FU (2,400mg/m2/48 hours) for patients with mCRC receiving triplet chemotherapy in the U.S.

Precise application of topical tranexamic acid to enhance endoscopic hemostasis for peptic ulcer bleeding: a randomized controlled study (with video)

Peptic ulcer recurrent bleeding occurs in 20% to 30% of patients after standard endoscopic hemostasis, particularly within 4 days after the procedure. The application of additional tranexamic acid (TXA) to the ulcer may enhance hemostasis. This study investigated the effectiveness of TXA powder application on bleeding ulcers during endoscopic hemostasis. This study enrolled patients who had peptic ulcer bleeding between March 2022 and February 2023. After undergoing standard endoscopic therapy, the patients were randomly assigned to either the TXA group or the standard group. In the TXA group, an additional 1.25 g of TXA powder was sprayed endoscopically on the ulcer. Both groups then received 3 days of high-dose (8 mg/h) continuous infusion proton pump inhibitor therapy. Second-look endoscopy was conducted on days 3 to 4. The primary end point of early treatment failure was defined as ulcer recurrent bleeding within 4 days or major stigmata of recent hemorrhage on the second-look endoscopy. Sixty patients (30 in each group) with peptic ulcer bleeding and balanced baseline characteristics were randomly assigned to a treatment group. The early treatment failure rate was lower in the TXA group (6.7%) than in the standard group (30%) (P= .042). The freedom from treatment failure periods for 4 and 28 days was significantly longer in the TXA group than in the standard group (P= .023). No adverse events from TXA were recorded. The precise delivery of topical TXA alongside standard endoscopic hemostasis reduced the early treatment failure rate in patients with bleeding peptic ulcers. (Clinical trial registration number: NCT05248321.).

Continuous Infusion of High Doses of Cefepime in Intensive Care Unit: Assessment of Steady-State Plasma Level and Incidence on Neurotoxicity.

Continuous infusion (CI) with high doses of cefepime is recommended in the empirical antimicrobial regimen of critically ill patients with suspected Gram-negative sepsis. This study aimed to determine factors associated with cefepime overdosing and the incidence of cefepime-induced neurotoxicity (CIN) in these patients. We performed a retrospective study including all patients receiving cefepime treatment between January 2019 and May 2022. The plasma level of cefepime defining overdosing was over 35 mg/L. Neurotoxicity was defined according to strict criteria and correlated with concomitant steady-state concentration of cefepime. Seventy-eight courses of cefepime treatment were analyzed. The mean cefepime plasma level at steady state was 59.8 ± 29.3 mg/L, and overdosing occurred in 80% of patients. Renal failure and a daily dose > 5 g were independently associated with overdosing. CIN was present in 30% of patients. In multivariate analysis, factors associated with CIN were chronic renal failure and a cefepime plasma concentration ≥ 60 mg/L. CIN was not associated with mortality. Overdosing is frequent in patients receiving high doses of cefepime by CI. Steady-state levels are higher than targeted therapeutic pharmacokinetic/pharmacodynamic objectives. The risk of CIN is important when the plasma concentration is ≥60 mg/L.

Successful Treatment of Bacteremia and Ventilator-Associated Pneumonia Caused by KPC/OXA-48-like Klebsiella pneumoniae Co-Producer with a Continuous Infusion of High-Dose Meropenem Plus Fosfomycin Guided by Real-Time Therapeutic Drug Monitoring.

Bacteremia and ventilator-associated pneumonia due to a pan-resistant Klebsiella pneumoniae strain co-producing KPC and OXA-48 carbapenemases was successfully treated in a COVID-19 critically ill patient with a combination therapy of a high-dose continuous infusion of meropenem (up to 3 g every 6 h, daily) plus fosfomycin (up to 24 g/daily) that was guided by real-time therapeutic drug monitoring. Clinical pharmacological advice was helpful in maximizing, over time, the pharmacodynamic target attainment of both antibiotics.

Infective endocarditis of a native aortic valve due to Pseudomonas aeruginosa complicated by progressive multi-drug resistance

Treatment of infective endocarditis secondary to Pseudomonas aeruginosa can be challenging because of this organism's ability to acquire antimicrobial resistance over time. We describe a patient with native aortic valve infective endocarditis due to P. aeruginosa who developed progressive multi-drug resistance while on therapy. The resistance mechanisms were characterized using whole-genome sequencing. We identified two mutations in subsequent isolates (dacB and OprD) that conferred resistance to anti-pseudomonal penicillins, cephalosporins, and carbapenems. The patient was treated with combination high-dose continuous infusion meropenem and ciprofloxacin therapy, in addition to bioprosthetic aortic valve replacement and repair of ventricular septal wall defect. Antibiotics were continued for 6 weeks post-cardiac surgery and the patient remains infection free 18 months post-completion of antibiotic therapy. Clinicians should be aware of the ability of P. aeruginosa to acquire resistance mechanisms in response to selective antibiotic pressures in high-inoculum infections such as infective endocarditis. The mutations identified in this case report correlated well with the evolving antimicrobial resistance profile observed.

Cost-effectiveness and clinical outcomes of intermittent/continuous proton pump inhibitors infusion in high bleeding risk of ulcers: A retrospective observational cohort study.

The purpose of this study was to evaluate the clinical outcomes, including patient prognosis and medication expense, of proton pump inhibitors administered by high-dose continuous infusion (HDC, 80 mg loading dose, then 8 mg/h for 72 hours) or non-high-dose intermittent infusion (NHDI, 40 mg qd or 40 mg q12 h, for 3 days) regimens in high-risk patients with bleeding peptic ulcers.In this retrospective cohort study, patients with peptic ulcers and endoscopic hemostasis between January, 2013 and December, 2015 were included. The primary endpoints were rebleeding and mortality rates within 7 days. The secondary endpoints were length of stay (LOS), transfusion units of packed red blood cells (PRBCs), and the number needed to treat.A total of 335 patients met the inclusion criteria during the 3-year follow-up period. The cumulative incidence of rebleeding within 7 days was 20.4% and 11.2% in the HDC and NHDI groups, respectively, with a significant difference (P = .021). The mortality rate was 12.1% and 7.3% in the HDC and NHDI groups, respectively, with no significant difference (P = .136). Univariate Cox proportional hazards model analysis showed that the risk of rebleeding within 7 days in the HDC group was higher than that in the NHDI group. The hazard ratio for HDC vs. NHDI was 1.93 (P = .021). There were significant differences in LOS (P = .034) and PRBC units (P = .005) for risk of rebleeding within 7 days, as well as in transfusion units of PRBCs for mortality rate analysis (p < 0.001), between the HDC and NHDI groups. The results showed that the NHDI regimen could reduce the risk of rebleeding within 7 days in 1 of 11 patients (number needed to treat = 11) and could reduce medication cost by US$ 400 to 800.The NHDI regimen showed a lower risk of rebleeding within 7 days, shorter LOS, and fewer PRBC units than that of the HDC regimen. Receiving NHDI has better cost-effective outcomes than that of HDC for patients with high-risk bleeding peptic ulcers.

Cerebrospinal Fluid Penetration of Vancomycin During Continuous Infusion Therapy in Patients With Nosocomial Ventriculitis.

This study aimed to evaluate the utility of a commercial kit used to measure serum vancomycin concentrations to determine vancomycin concentrations in cerebrospinal fluid (CSF) samples and evaluate CSF penetration when administered as a continuous high-dose infusion in patients with nosocomial ventriculitis. This study included patients with external ventricular drain infection who were admitted to the intensive care unit between January 2018 and September 2020. After validation, CSF samples from 33 patients were collected. All patients received 30 mg/kg of vancomycin as a loading dose followed by 60 mg/kg as a maintenance dose in continuous infusion; all CSF samples were collected at least 48 hours after the first dose. Thirty-three patients were enrolled in this study. The median serum creatinine level was 0.66 mg/dL (0.5-0.92; n = 30), and median creatinine clearance was 119.2 mL/min (64.6-138.4; n = 13). The median serum vancomycin 24-hour area under the curve (AUC24h) was 838 mg*h/L (515-1010). The median CSF vancomycin concentration was 5.20 mg/L (1.95-12.4). Median serum vancomycin concentration was 34.9 mg/L (21.47-42.1), and median CSF/serum ratio was 18.6% (8.4-41.5). Acute renal injury occurred in 21% (n = 7) of the patients by the end of the therapy. In addition, the vancomycin CSF/serum ratio was positively correlated with the median serum creatinine level (r = 0.670; P = 0.004). Commercial vancomycin kits used to measure serum samples may be used to evaluate vancomycin concentrations in the CSF. Vancomycin penetration into CSF was 18.6%.

CORONARY VASOSPASM ASSOCIATED WITH 5-FLUOROURACIL CHEMOTHERAPY

SESSION TITLE: Medical Student/Resident Cardiovascular Disease Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: 5-Fluorouracil (5FU) is the third most commonly used chemotherapeutic agent in the treatment of solid malignancies, particularly colorectal and pancreatic neoplasms. (1,2) Coronary vasospasm associated with 5FU is a known complication. (3) Cardiotoxicity occurs in 1% to 18% of patients receiving 5FU, and the incidence of this complication is on the rise.(4) The objective of this report is to highlight the characteristics of this uncommon complication. CASE PRESENTATION: A 66-year-old male with a past medical history of coronary artery disease status-post 4-vessel coronary artery bypass graft surgery and stage 4 colon adenocarcinoma with metastasis to the liver, presented to the emergency department (ED) with complaints of sudden onset of burning deep sub-sternal chest pain with no radiation. The chest pain began approximately eight hours after his first round of 5FU, leuocorin and eloxatin (FOLFOX) chemotherapy. In the ED he was given aspirin and heparin. EKG was concerning for ST-segment elevation myocardial infarction in the inferior leads. Troponins were negative (<0.01). A subsequent left heart catheterization revealed patent grafts and normal coronary arteries. An echocardiogram showed no acute wall motion abnormalities and an ejection fraction of 65%. The 5FU was discontinued and the patient’s chest pain improved. He was discharged with sublingual nitroglycerin and diltiazem. Two weeks later, the patient returned with similar chest pain after his second cycle with 5FU, leuocorin and eloxatin (FOLFOX). The symptoms of his coronary artery vasospasm were believed to be due to 5FU chemotherapy. He was further instructed to go to the cardiovascular ICU to receive nitroglycerine infusions before each cycle of FOLFOX. Unfortunately, the patient expired two months after starting chemotherapy; from cardiopulmonary arrest secondary to sepsis. DISCUSSION: This is a case of a 66-year-old male with a past medical history of coronary artery disease and stage 4 colon adenocarcinoma on 5-Fluorouracil, leuocorin and eloxatin (FOLFOX) chemotherapy presenting for coronary vasospasm likely from 5-Fluorouracil. Cardiotoxicity related to 5FU is poorly understood. Leading theories of the mechanism of 5FU-induced coronary vasospasm seem to involve 5FU's modification of smooth muscle tone. (5,6) Patients on 5FU with coronary vasospasm may have ECG findings suggestive of occlusion, (3) similar to our patient. Treatment of affected patients is determined by confirmation of 5FU as the definitive cause of the coronary vasospasm, as well as the requirement of 5FU as the only suitable chemotherapeutic agent. If possible, care providers should consider switching to an acceptable chemotherapeutic substitute. CONCLUSIONS: In conclusion, consideration should be given for patients with coronary artery disease starting 5-Fluorouracil chemotherapy. Reference #1: 1. Grem JL. 5-Fluorouracil: forty-plus and still ticking. A review of its preclinical and clinical development. Invest New Drugs 2000; 18: 299-313. 2. Myers CE. The pharmacology of the fluoropyrimidines. Pharmacol Rev 1981; 33: 1-15. 3. de Forni M, Malet-Martino MC, Jailais P, et al. Cardiotoxicity of high-dose continuous infusion fluorouracil: a prospective clinical study. Clin Oncol 1992; 10: 1795-1801. 4. Lestuzzi C, Vaccher E, Talamini R, et al. Effort myocardial ischemia during chemotherapy with 5-fluorouracil: an underestimated risk. Ann Oncol 2014; 25: 1059-1064. 5. Bonetti PO, Lerman LO and Lerman A. Endothelial dysfunction: a marker of atherosclerotic risk. Arterioscler Throb Vasc Biol 2003, 23: 168-175. 6. Reddy KG, Nair RN, Sheehan HM, et al. Evidence that selective endothelial dysfunction may occur in the absence of angiographic or ultrasound atherosclerosis in patients with risk factors for artherosclerosis. I Am Coll Cardio! 1994; 23: 833-843. DISCLOSURES: No relevant relationships by Ahmad ababneh, source=Web Response No relevant relationships by HANAD BASHIR, source=Web Response No relevant relationships by Ahmad JABRI, source=Web Response No relevant relationships by Gauranga Mahalwar, source=Web Response

Very High-Dose Furosemide Continuous Infusions: A Case Series

BackgroundThere is paucity of data evaluating the efficacy and safety of very high-dose furosemide continuous infusions (≥40 mg/h) for volume removal. This infusion is a novel strategy of loop diuretic administration that may add valuable data to current literature. Methods and ResultsThis was a retrospective chart review. Patients were eligible for inclusion if prescribed a very high-dose furosemide infusion (defined as ≥40 mg/h, up to 240 mg/h) from April 1, 2017, to January 1, 2019, at Thomas Jefferson University Hospital. Data collected included the change in cumulative urine output, net urine output, incidence of acute kidney injury, occurrences of hypotension, electrolyte abnormalities, body weight, and ototoxicity. Twenty-two patients were included in this analysis. The median change in 24-hour urine output from before to after very high-dose continuous furosemide infusion increased from 1193 mL at 24 hours before infusion initiation to 3518 mL at 24 hours after infusion initiation (P < .01). Serum creatinine increased 24 hours after infusion initiation but decreased within 48 hours. There were no electrolyte abnormalities. Out of 22 patients, only 2 had an occurrence of hypotension. No patients were reported to have ototoxicity. ConclusionsVery high-dose furosemide continuous infusions provide a significant increase in diuresis without worsening renal function, disturbing electrolytes, or increasing the risk of ototoxicity. Further studies are necessary to examine the efficacy and safety of this novel strategy.

Should we reconsider cefazolin for treating staphylococcal meningitis? A retrospective analysis of cefazolin and cloxacillin cerebrospinal fluid levels in patients treated for staphylococcal meningitis

ObjectivesTo assess the meningeal penetration of cefazolin and cloxacillin in individuals treated for methicillin-susceptible staphylococcal meningitis. MethodsWe retrospectively identified individuals treated for Staphylococcus meningitis with measurements of cefazolin or cloxacillin concentrations in cerebrospinal fluid (CSF) using a validated assay of liquid chromatography coupled with mass spectrometry at the Nantes University Hospital between January 2009 and October 2019. Staphylococcus meningitis was defined by a compatible clinical presentation and a microbiological confirmation (positive CSF culture or positive specific PCR). Medical charts were retrospectively reviewed to collect microbiological and clinical data, and to assess therapeutic success. ResultsAmong the 17 included individuals, eight (47%) were treated with cefazolin and nine (53%) with cloxacillin. Median daily dosages of cefazolin and cloxacillin were 8 g (range 6–12 g) and 12 g (range 10–13 g), respectively. Cefazolin and cloxacillin were mainly administered by continuous infusion. Eleven individuals (65%) were men, median (interquartile range (IQR)) age was 54 years (50; 70), 14 (82%) had postoperative meningitis and 3 (18%) had haematogenous meningitis. Median (IQR) antibiotic CSF concentrations were 2.8 mg/L (2.1; 5.2) and 0.66 mg/L (0.5; 0.9) for cefazolin and cloxacillin groups, respectively. Cloxacillin was discontinued in two individuals for therapeutic failure. ConclusionsPatients with staphylococcal meningitis treated with high-dose continuous intravenous infusion of cefazolin achieved therapeutic concentrations in CSF. Cefazolin appears to be a therapeutic candidate that should be properly evaluated in this indication.

Successful treatment with continuous high-dose 5-fluorouracil infusion, followed by oral capecitabine in a patient with advanced gastric cancer with bone marrow metastasis and microangiopathic hemolytic anemia

A 61-year-old male with a history of Stage 1A gastric body adenocarcinoma and s/p radical subtotal gastrectomy + B-II reconstruction 5 years previously presented with general malaise and bone pain. A hemogram revealed severe anemia and thrombocytopenia, which were refractory to blood transfusion. A peripheral blood smear showed marked thrombocytopenia with numerous fragmented red blood cells and normoblasts. A bone marrow biopsy showed metastatic adenocarcinoma of gastric origin. Therefore, he was diagnosed with cancer-associated microangiopathic hemolytic anemia (MAHA). In addition to aggressive transfusion support, high-dose continuous 5-fluorouracil infusion was administered, and the MAHA and thrombocytopenia dramatically resolved. Capecitabine was subsequently administered orally at the outpatient clinic, and his disease was well controlled without the recurrence of MAHA or thrombocytopenia for 1 year. Although most chemotherapies may aggravate cytopenia, our case illustrates that effective chemotherapy can not only control cancer-associated MAHA but also restore cytopenia to normal.

Management of Status Epilepticus

AbstractStatus epilepticus (SE) is a life-threatening neurologic condition that requires immediate assessment and intervention. Over the past few decades, the duration of seizure required to define status epilepticus has shortened, reflecting the need to start therapy without the slightest delay. The focus of this review is on the management of convulsive and nonconvulsive status epilepticus in critically ill patients. Initial treatment of both forms of status epilepticus includes immediate assessment and stabilization, and administration of rapidly acting benzodiazepine therapy followed by nonbenzodiazepine antiepileptic drug. Refractory and super-refractory status epilepticus (RSE and SRSE) pose a lot of therapeutic problems, necessitating the administration of continuous infusion of high doses of anesthetic agents, and carry a high risk of debilitating morbidity as well as mortality.

Continuous high-dose infusion of doripenem in a pneumonia patient infected by carbapenem-resistant Pseudomonas aeruginosa: a case report

BackgroundDespite the high mortality of patients with sepsis and carbapenem-resistant bacteria infection, appropriate antimicrobial therapies are yet to be established. Here, we have reported the case of a patient with pneumonia that subsequently developed by carbapenem-resistant Pseudomonas aeruginosa infection and was treated with a continuous high-dose infusion of doripenem.Case presentationWe started a continuous intravenous infusion of doripenem 3 g/day although the 59-year-old woman (body weight, 45 kg) had developed septic acute kidney injury, followed by continuous renal replacement therapy (the effluent flow rate was 650 mL/h). The minimum inhibitory concentration (MIC) of doripenem was 8 mg/L. The concentration of unbound doripenem in the serum was measured by using high-performance liquid chromatography. Twenty hours after the initial dose, the patient’s serum level of doripenem was 47.8 μg/mL; the level decreased to 33.6 μg/mL at 111 h after initial dosing. The unbound doripenem concentration in the serum was maintained four times above the MIC throughout the treatment. After the completion of 11 days of dosing, the patient was discharged from the intensive care unit. During the treatment period, the MIC remained at 8 mg/L.ConclusionsA continuous high-dose infusion of doripenem is a potentially efficient strategy for the treatment of antimicrobial-resistant bacteria. Moreover, therapeutic drug monitoring may be useful for patients displaying variable pharmacokinetics, because the MIC is generally high in resistant bacteria.

The Effectiveness of Standard Single Dose Omeprazole vs. High Dose Continuous Infusion in High-risk Critically Ill Patients

Objectives: The present study was carried out to investigate the beneficial effects of high dose omeprazole versus standard low dose as a prophylaxis against upper GIT bleeding in high risk critically ill patients. Methods: A hundred and ten high risk critically ill patients were divided into two groups, fifty-five patients each. Group A received intravenous (IV) omeprazole 40 mg bolus dose once daily followed by normal saline infusion. Group B received IV bolus of 80 mg omeprazole followed by 8 mg/h infusion. The treatment was for the whole period of ICU stay. Early morning gastric pH, residual gastric volume, signs of significant upper GIT bleeding, ICU stay Hb, number of ICU days without ventilator, ICU stay hemoglobin (Hb), number of red cell units transfused in ICU, ICU stay, and numbers of ICU survivors were recorded. Results: Gastric pH was higher in group B compared to group A (p<0.05). The number of patients developed significant upper GIT bleeding were significantly higher in group A. Group A had lower ICU Hb levels and used significant higher number of RBC units. ICU stay was significantly higher in group A compared to group B (p=0.02). There were no statistical differences regarding the number of ICU days without ventilator and ICU survivors between both groups (P<0.05). Conclusions: High dose PPI continuous infusion can reduce the incidence of upper GIT bleeding in high risk critically ill patients. High dose PPI can reduce ICU stay with no effect on ICU survivor rate.

Population pharmacokinetics of continuous infusion of piperacillin in critically ill patients

Dosing recommendations for continuous infusion of piperacillin, a broad-spectrum beta-lactam antibiotic, are mainly guided by outputs from population pharmacokinetic models constructed with intermittent infusion data. However, the probability of target attainment in patients receiving piperacillin by continuous infusion may be overestimated when drug clearance estimates from population pharmacokinetic models based on intermittent infusion data are used, especially when higher doses (e.g. 16 g/24 h or more) are simulated. Therefore, the purpose of this study was to describe the population pharmacokinetics of piperacillin when infused continuously in critically ill patients. For this analysis, 270 plasma samples from 110 critically ill patients receiving piperacillin were available for population pharmacokinetic model building. A one-compartment model with linear clearance best described the concentration–time data. The mean ± standard deviation parameter estimates were 8.38 ± 9.91 L/h for drug clearance and 25.54 ± 3.65 L for volume of distribution. Creatinine clearance improved the model fit and was supported for inclusion as a covariate. In critically ill patients with renal clearance higher than 90 mL/min/1.73 m2, a high-dose continuous infusion of 24 g/24 h is insufficient to achieve adequate exposure (pharmacokinetic/pharmacodynamic target of 100% fT>4 x MIC) against susceptible Pseudomonas aerginosa isolates (MIC ≤16 mg/L). These findings suggest that merely increasing the dose of piperacillin, even with continuous infusion, may not always result in adequate piperacillin exposure. This should be confirmed by evaluating piperacillin target attainment rates in critically ill patients exhibiting high renal clearance.

Population Pharmacokinetics of High-Dose Continuous-Infusion Meropenem and Considerations for Use in the Treatment of Infections Due to KPC-Producing Klebsiella pneumoniae.

We assessed the population pharmacokinetics of high-dose continuous-infusion (HDCI) meropenem in a cohort of patients with Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae (KPC-Kp) infections. Monte Carlo simulations were used to define the permissible HDCI meropenem regimens that could be safely considered for the treatment of KPC-Kp infections due to meropenem-resistant strains. Permissible doses were arbitrarily defined as those associated with a ≤10% to 15% likelihood of meropenem steady-state concentrations (Css) of >100 mg/liter. Probabilities of target attainment (PTA) of four incremental pharmacodynamic determinants for meropenem efficacy (100% T>1×MIC, 100% T>2×MIC, 100% T>3×MIC, and 100% T>4×MIC, where "T>MIC" represents the time during which the plasma concentration of this time-dependent antibacterial agent is maintained above the MIC for the pathogen) in relation to different classes of renal function were calculated. The cumulative fractions of response (CFR) for the permissible HDCI meropenem regimens were calculated against the MIC distribution of the KPC-Kp clinical isolates that were collected routinely at our University Hospital between 2013 and 2016 (n = 169). Ninety-seven meropenem Css were included in the analysis. The final model included creatinine clearance (CrCL) as a covariate and explained 94% of the population variability. Monte Carlo simulations based on licensed dosages of up to 6 g/day predicted an acceptable PTA (>80%) of 100% T>1×MIC against KPC-Kp with a meropenem MIC of ≤32 mg/liter in patients with a CrCL level of <130 ml/min. Dosages of 8 g/day were needed for achieving the same target in patients with CrCL at levels of 130 to 200 ml/min. In dealing with pathogens with a meropenem MIC of 64 mg/liter, HDCI regimens using meropenem at higher than licensed levels should be considered. In these cases, real-time therapeutic drug monitoring could be a useful adjunct for optimized care. The predicted CFR were >75% in all of the classes of renal function.

Results of two sequential phase II studies of interleukin-2 (IL2) in metastatic renal cell carcinoma and melanoma: high-dose continuous intravenous IL2 infusion and subcutaneous IL2 administration in combination with alpha interferon

The results of two sequential trials, the first one with high dose interleukin 2 (IL2) by continuous intravenous infusion and the second one with subcutaneous IL2 and alpha-interferon (alpha IFN), performed in consecutive patients with metastatic melanoma and renal carcinoma at the Clinica Universitaria de Navarra are presented. In the high-dose continuous IL2 trial, recombinant IL2, 18 x 10(6) IU/m2, was administered daily by continuous infusion five days a week for two weeks, and the treatment cycle was repeated after a rest of 2 weeks. Twenty two patients were treated and objective responses were observed in 3 (13.3%). Toxicity was frequent and severe, and all but one required dose reduction. The mortality rate was 9% (2/22). In the subcutaneous IL2 and alpha IFN trial, subcutaneous IL2, 4.8 x 10(6) IU/m2, was administered daily, five days a week, for 3 consecutive weeks. IL2 dose was given every 8 hours on the first day and every 12 hours on the second day, as a loading induction dose. Concomitant alpha-IFN, 3 x 10(6) IU/m2 was given subcutaneously once a day on days 1, 3 and 5 weekly each week for the duration of IL2 therapy. Of the 24 patients treated with this combination, 3 partial responses were noticed (12.5%) and the toxicity was mild to moderate. These results suggest that both, IL2 alone or IL2 in combination with alpha-IFN are minimally active and that any improvement in tolerance might impair its antitumor activity.

Might real-time pharmacokinetic/pharmacodynamic optimisation of high-dose continuous-infusion meropenem improve clinical cure in infections caused by KPC-producing Klebsiella pneumoniae?

The effect of real-time pharmacokinetic/pharmacodynamic (PK/PD) optimisation of high-dose continuous-infusion meropenem on the clinical outcome of patients receiving combination antimicrobial therapy for treatment of KPC-producing Klebsiella pneumoniae (KPC-Kp) infections was retrospectively assessed. Data for all patients with KPC-Kp-related infections who received antimicrobial combination therapy containing high-dose continuous-infusion meropenem optimised by means of therapeutic drug monitoring (TDM) were retrieved. Optimal PK/PD exposure was considered a steady-state concentration to minimum inhibitory concentration ratio (Css/MIC) of 1–4. Univariate binary logistic regression analysis was performed to identify independent predictors of clinical outcome. Among the 30 eligible patients, 53.3% had infections caused by meropenem-resistant KPC-Kp (MIC ≥ 16 mg/L). Tigecycline and colistin were the two antimicrobials most frequently combined with meropenem. Mean doses of continuous-infusion meropenem ranged from 1.7 to 13.2 g/daily. The Css/MIC ratio was ≥1 in 73.3% of cases and ≥4 in 50.0%. Clinical outcome was successful in 73.3% of cases after a median treatment length of 14.0 days. In univariate analysis, a significant correlation with successful clinical outcome was found for a Css/MIC ratio ≥1 (OR = 10.556, 95% CI 1.612–69.122; P = 0.014), a Css/MIC ratio ≥4 (OR = 12.250, 95% CI 1.268–118.361; P = 0.030) and a Charlson co-morbidity index of ≥4 (OR = 0.158, 95% CI 0.025–0.999; P = 0.05). High-dose continuous-infusion meropenem optimised by means of real-time TDM may represent a valuable tool in improving clinical outcome when dealing with the treatment of infections caused by KPC-Kp with a meropenem MIC ≤ 64 mg/L.

Probable Nonconvulsive Status Epilepticus With the Use of High-Dose Continuous Infusion Ceftazidime

Multidrug resistant (MDR) bacterial infections are a major concern of health care providers due to their increasing incidence and associated mortality. In some cases, few or no antibiotics have preserved activity. Beta-lactam administration via continuous infusion can optimize time over minimum inhibitory concentration (MIC). In some cases, use of high-dose continuous infusion (HDCI) may be necessary to achieve serum levels in excess of nonsusceptible MIC values. The use of HDCI beta-lactams is not without risk, specifically neurotoxic adverse effects, which appear dose related. We describe a 64-year-old male who experienced myoclonus and nonconvulsive status epilepticus while receiving HDCI ceftazidime for treatment of multidrug resistant Pseudomonas aeruginosa bacteremia. This report serves as a cautionary example of the potential toxicities associated with HDCI beta-lactams and supports the importance of risk–benefit analysis prior to and during treatment. Additionally, the use of serum drug level monitoring may be necessary to better prevent or predict toxicity.