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In vitro activities of clindamycin, imipenem, metronidazole, and piperacillin-tazobactam against susceptible and resistant isolates of Bacteroides fragilis evaluated by kill kinetics. Antimicrob Agents Chemother 2012; 56:3413-6. [PMID: 22430962 DOI: 10.1128/aac.00099-12] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aim of the present study was to investigate the activities of clindamycin, imipenem, metronidazole, and piperacillin-tazobactam against 12 Bacteroides fragilis isolates (resistant and susceptible strains) by kill kinetics over 24 h. In contrast to the other antimicrobial agents, clindamycin did not affect strains with MICs of >8.0 μg/ml. For those strains with MICs of ≤ 8.0 μg/ml, all employed antibiotics except clindamycin showed nearly bactericidal activity. Metronidazole proved to be the most active antimicrobial agent.
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Rodvold KA, George JM, Yoo L. Penetration of anti-infective agents into pulmonary epithelial lining fluid: focus on antibacterial agents. Clin Pharmacokinet 2012; 50:637-64. [PMID: 21895037 DOI: 10.2165/11594090-000000000-00000] [Citation(s) in RCA: 177] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The exposure-response relationship of anti-infective agents at the site of infection is currently being re-examined. Epithelial lining fluid (ELF) has been suggested as the site (compartment) of antimicrobial activity against lung infections caused by extracellular pathogens. There have been an extensive number of studies conducted during the past 20 years to determine drug penetration into ELF and to compare plasma and ELF concentrations of anti-infective agents. The majority of these studies estimated ELF drug concentrations by the method of urea dilution and involved either healthy adult subjects or patients undergoing diagnostic bronchoscopy. Antibacterial agents such as macrolides, ketolides, newer fluoroquinolones and oxazolidinones have ELF to plasma concentration ratios of >1. In comparison, β-lactams, aminoglycosides and glycopeptides have ELF to plasma concentration ratios of ≤1. Potential explanations (e.g. drug transporters, overestimation of the ELF volume, lysis of cells) for why these differences in ELF penetration occur among antibacterial classes need further investigation. The relationship between ELF concentrations and clinical outcomes has been under-studied. In vitro pharmacodynamic models, using simulated ELF and plasma concentrations, have been used to examine the eradication rates of resistant and susceptible pathogens and to explain why selected anti-infective agents (e.g. those with ELF to plasma concentration ratios of >1) are less likely to be associated with clinical treatment failures. Population pharmacokinetic modelling and Monte Carlo simulations have recently been used and permit ELF and plasma concentrations to be evaluated with regard to achievement of target attainment rates. These mathematical modelling techniques have also allowed further examination of drug doses and differences in the time courses of ELF and plasma concentrations as potential explanations for clinical and microbiological effects seen in clinical trials. Further studies are warranted in patients with lower respiratory tract infections to confirm and explore the relationships between ELF concentrations, clinical and microbiological outcomes, and pharmacodynamic parameters.
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Resistance emergence mechanism and mechanism of resistance suppression by tobramycin for cefepime for Pseudomonas aeruginosa. Antimicrob Agents Chemother 2011; 56:231-42. [PMID: 22005996 DOI: 10.1128/aac.05252-11] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The panoply of resistance mechanisms in Pseudomonas aeruginosa makes resistance suppression difficult. Defining optimal regimens is critical. Cefepime is a cephalosporin whose 3' side chain provides some stability against AmpC β-lactamases. We examined the activity of cefepime against P. aeruginosa wild-type strain PAO1 and its isogenic AmpC stably derepressed mutant in our hollow-fiber infection model. Dose-ranging studies demonstrated complete failure with resistance emergence (both isolates). Inoculum range studies demonstrated ultimate failure for all inocula. Lower inocula failed last (10 days to 2 weeks). Addition of a β-lactamase inhibitor suppressed resistance even with the stably derepressed isolate. Tobramycin combination studies demonstrated resistance suppression in both the wild-type and the stably derepressed isolates. Quantitating the RNA message by quantitative PCR demonstrated that tobramycin decreased the message relative to that in cefepime-alone experiments. Western blotting with AmpC-specific antibody for P. aeruginosa demonstrated decreased expression. We concluded that suppression of β-lactamase expression by tobramycin (a protein synthesis inhibitor) was at least part of the mechanism behind resistance suppression. Monte Carlo simulation demonstrated that a regimen of 2 g of cefepime every 8 h plus 7 mg/kg of body weight of tobramycin daily would provide robust resistance suppression for Pseudomonas isolates with cefepime MIC values up to 8 mg/liter and tobramycin MIC values up to 1 mg/liter. For P. aeruginosa resistance suppression, combination therapy is critical.
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Gonçalves-Pereira J, Póvoa P. Antibiotics in critically ill patients: a systematic review of the pharmacokinetics of β-lactams. Crit Care 2011; 15:R206. [PMID: 21914174 PMCID: PMC3334750 DOI: 10.1186/cc10441] [Citation(s) in RCA: 287] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 06/28/2011] [Accepted: 09/13/2011] [Indexed: 01/02/2023] Open
Abstract
INTRODUCTION Several reports have shown marked heterogeneity of antibiotic pharmacokinetics (PK) in patients admitted to ICUs, which might potentially affect outcomes. Therefore, the pharmacodynamic (PD) parameter of the efficacy of β-lactam antibiotics, that is, the time that its concentration is above the bacteria minimal inhibitory concentration (T > MIC), cannot be safely extrapolated from data derived from the PK of healthy volunteers. METHODS We performed a full review of published studies addressing the PK of intravenous β-lactam antibiotics given to infected ICU patients. Study selection comprised a comprehensive bibliographic search of the PubMed database and bibliographic references in relevant reviews from January 1966 to December 2010. We selected only English-language articles reporting studies addressing β-lactam antibiotics that had been described in at least five previously published studies. Studies of the PK of patients undergoing renal replacement therapy were excluded. RESULTS A total of 57 studies addressing six different β-lactam antibiotics (meropenem, imipenem, piperacillin, cefpirome, cefepime and ceftazidime) were selected. Significant PK heterogeneity was noted, with a broad, more than twofold variation both of volume of distribution and of drug clearance (Cl). The correlation of antibiotic Cl with creatinine clearance was usually reported. Consequently, in ICU patients, β-lactam antibiotic half-life and T > MIC were virtually unpredictable, especially in those patients with normal renal function. A better PD profile was usually obtained by prolonged or even continuous infusion. Tissue penetration was also found to be compromised in critically ill patients with septic shock. CONCLUSIONS The PK of β-lactam antibiotics are heterogeneous and largely unpredictable in ICU patients. Consequently, the dosing of antibiotics should be supported by PK concepts, including data derived from studies of the PK of ICU patients and therapeutic drug monitoring.
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Affiliation(s)
- Joao Gonçalves-Pereira
- Polyvalent Intensive Care Unit, São Francisco Xavier Hospital, Estrada do Forte do Alto do Duque, 1449-005 Lisboa, Portugal
- CEDOC, Faculty of Medical Sciences, New University of Lisbon, Campo dos Mártires da Pátria, 130, 1169-056 Lisboa, Portugal
| | - Pedro Póvoa
- Polyvalent Intensive Care Unit, São Francisco Xavier Hospital, Estrada do Forte do Alto do Duque, 1449-005 Lisboa, Portugal
- CEDOC, Faculty of Medical Sciences, New University of Lisbon, Campo dos Mártires da Pátria, 130, 1169-056 Lisboa, Portugal
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Clinical practice guidelines for hospital-acquired pneumonia and ventilator-associated pneumonia in adults. CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY 2011; 19:19-53. [PMID: 19145262 DOI: 10.1155/2008/593289] [Citation(s) in RCA: 153] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Accepted: 12/19/2007] [Indexed: 02/07/2023]
Abstract
Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are important causes of morbidity and mortality, with mortality rates approaching 62%. HAP and VAP are the second most common cause of nosocomial infection overall, but are the most common cause documented in the intensive care unit setting. In addition, HAP and VAP produce the highest mortality associated with nosocomial infection. As a result, evidence-based guidelines were prepared detailing the epidemiology, microbial etiology, risk factors and clinical manifestations of HAP and VAP. Furthermore, an approach based on the available data, expert opinion and current practice for the provision of care within the Canadian health care system was used to determine risk stratification schemas to enable appropriate diagnosis, antimicrobial management and nonantimicrobial management of HAP and VAP. Finally, prevention and risk-reduction strategies to reduce the risk of acquiring these infections were collated. Future initiatives to enhance more rapid diagnosis and to effect better treatment for resistant pathogens are necessary to reduce morbidity and improve survival.
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Drusano GL. What are the properties that make an antibiotic acceptable for therapy of community-acquired pneumonia? J Antimicrob Chemother 2011; 66 Suppl 3:iii61-7. [PMID: 21482571 DOI: 10.1093/jac/dkr100] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The factors associated with identifying an appropriate dose and schedule of an antimicrobial agent for treatment of hospitalized, seriously ill patients with pneumonia are straightforward. Information is required about the potency of the agent for typical pathogens likely to be encountered with pneumonia. It is helpful to understand the utility of the agent against pathogens that express resistance to older antimicrobial agents. The agent must be able to gain access to the site of infection at the dose and schedule chosen and at concentrations high enough to attain microbiologically effective targets [e.g. 1 or 2 log(10) (cfu/g) bacterial cell kill, accounting for between-patient variability]. Finally, therapeutic concentrations should be attained quickly at the primary site of infection to optimize clinical outcomes. When considering all of these factors, it is expected that ceftaroline fosamil will be a valuable addition to the therapeutic armamentarium for management of community-acquired pneumonia.
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Lodise TP, Sorgel F, Melnick D, Mason B, Kinzig M, Drusano GL. Penetration of meropenem into epithelial lining fluid of patients with ventilator-associated pneumonia. Antimicrob Agents Chemother 2011; 55:1606-10. [PMID: 21300830 PMCID: PMC3067164 DOI: 10.1128/aac.01330-10] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 12/30/2010] [Accepted: 01/21/2011] [Indexed: 11/20/2022] Open
Abstract
Antibiotic penetration to the infection site is critical for obtaining a good clinical outcome in patients with ventilator-associated pneumonia (VAP). Surprisingly few studies have quantified the penetration of β-lactam agents into the lung, as measured by the ratio of area under the concentration-time curve (AUC) in epithelial lining fluid (ELF) to AUC in plasma (AUC(ELF)/AUC(plasma) ratio). These have typically involved noninfected patients. This study examines the penetration and pharmacodynamics of meropenem in the ELF among patients with VAP. Meropenem plasma and ELF concentration-time data were obtained from patients in a multicenter clinical trial. Concentration-time profiles in plasma and ELF were simultaneously modeled using a three-compartment model with zero-order infusion and first-order elimination and transfer (big nonparametric adaptive grid [BigNPAG]). A Monte Carlo simulation was performed to estimate the range of ELF/plasma penetration ratios one would expect to observe in patients with VAP, as measured by the AUC(ELF)/AUC(plasma) ratio. The range of AUC(ELF)/AUC(plasma) penetration ratios predicted by the Monte Carlo simulation was large. The 10th percentile of lung penetration was 3.7%, while the 90th percentile of penetration was 178%. The variability of ELF penetration is such that if relatively high ELF exposure targets are required to attain multilog kill or resistance suppression for bacteria like Pseudomonas aeruginosa, then even receiving the largest licensed dose of meropenem with an optimal prolonged infusion may not result in target attainment for a substantial fraction of the population.
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Affiliation(s)
- T. P. Lodise
- Ordway Research Institute, Albany, New York, Albany College of Pharmacy and Health Sciences, Albany, New York, IBMP, Nurnberg-Heroldsberg, Germany, Department of Pharmacology, University of Duisburg-Essen, Essen, Germany, AstraZeneca Pharmaceuticals LP, Wilmington, Delaware
| | - F. Sorgel
- Ordway Research Institute, Albany, New York, Albany College of Pharmacy and Health Sciences, Albany, New York, IBMP, Nurnberg-Heroldsberg, Germany, Department of Pharmacology, University of Duisburg-Essen, Essen, Germany, AstraZeneca Pharmaceuticals LP, Wilmington, Delaware
| | - D. Melnick
- Ordway Research Institute, Albany, New York, Albany College of Pharmacy and Health Sciences, Albany, New York, IBMP, Nurnberg-Heroldsberg, Germany, Department of Pharmacology, University of Duisburg-Essen, Essen, Germany, AstraZeneca Pharmaceuticals LP, Wilmington, Delaware
| | - B. Mason
- Ordway Research Institute, Albany, New York, Albany College of Pharmacy and Health Sciences, Albany, New York, IBMP, Nurnberg-Heroldsberg, Germany, Department of Pharmacology, University of Duisburg-Essen, Essen, Germany, AstraZeneca Pharmaceuticals LP, Wilmington, Delaware
| | - M. Kinzig
- Ordway Research Institute, Albany, New York, Albany College of Pharmacy and Health Sciences, Albany, New York, IBMP, Nurnberg-Heroldsberg, Germany, Department of Pharmacology, University of Duisburg-Essen, Essen, Germany, AstraZeneca Pharmaceuticals LP, Wilmington, Delaware
| | - G. L. Drusano
- Ordway Research Institute, Albany, New York, Albany College of Pharmacy and Health Sciences, Albany, New York, IBMP, Nurnberg-Heroldsberg, Germany, Department of Pharmacology, University of Duisburg-Essen, Essen, Germany, AstraZeneca Pharmaceuticals LP, Wilmington, Delaware
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Varghese JM, Roberts JA, Lipman J. Antimicrobial Pharmacokinetic and Pharmacodynamic Issues in the Critically Ill with Severe Sepsis and Septic Shock. Crit Care Clin 2011; 27:19-34. [DOI: 10.1016/j.ccc.2010.09.006] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Boonsarngsuk V, Niyompattama A, Teosirimongkol C, Sriwanichrak K. False-positive serum and bronchoalveolar lavage Aspergillus galactomannan assays caused by different antibiotics. ACTA ACUST UNITED AC 2010; 42:461-8. [PMID: 20192889 DOI: 10.3109/00365541003602064] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Our objective was to identify false-positive serum and bronchoalveolar lavage (BAL) fluid galactomannan (GM) tests caused by various antibiotics commonly used in general practice. Serum and BAL samples from patients who did not have the diagnostic criteria of invasive aspergillosis and received different antibiotics were prospectively analyzed for GM. Serum and BAL samples were also collected from patients who did not receive antibiotics. At the cut-off index of >or=0.5, false-positive serum results were found in patients who received amoxicillin-clavulanate, piperacillin-tazobactam, cefepime, and cefoperazone-sulbactam (26.7%, 58.3%, 14.3%, and 66.7%, respectively). Fungal colonization in BAL samples had a higher BAL GM than those without fungal colonization. In 71 patients who had a negative BAL culture for fungi, at the cut-off value of >or=1.0, false-positive BAL fluid results were found in patients who received amoxicillin-clavulanate (27.3%), piperacillin-tazobactam (50%), cefepime (16.7%), carbapenem (45.5%), and ceftriaxone (45.5%). False-positive serum and BAL GM assays were also detected in patients who did not receive any antibiotics. In summary, this study demonstrates the false-positive GM levels in serum and BAL caused by beta-lactam antibiotics that are commonly used in general practice. Physicians should be aware of this possible interference.
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Affiliation(s)
- Viboon Boonsarngsuk
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
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Pea F, Viale P. Bench-to-bedside review: Appropriate antibiotic therapy in severe sepsis and septic shock--does the dose matter? CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2009; 13:214. [PMID: 19519961 PMCID: PMC2717408 DOI: 10.1186/cc7774] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Appropriate antibiotic therapy in patients with severe sepsis and septic shock should mean prompt achievement and maintenance of optimal exposure at the infection site with broad-spectrum antimicrobial agents administered in a timely manner. Once the causative pathogens have been identified and tested for in vitro susceptibility, subsequent de-escalation of antimicrobial therapy should be applied whenever feasible. The goal of appropriate antibiotic therapy must be pursued resolutely and with continuity, in view of the ongoing explosion of antibiotic-resistant infections that plague the intensive care unit setting and of the continued decrease in new antibiotics emerging. This article provides some principles for the correct handling of antimicrobial dosing regimens in patients with severe sepsis and septic shock, in whom various pathophysiological conditions may significantly alter the pharmacokinetic behaviour of drugs.
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Affiliation(s)
- Federico Pea
- Department of Experimental and Clinical Pathology, Institute of Clinical Pharmacology & Toxicology, Medical School, University of Udine, 33100 Udine, Italy.
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Population pharmacokinetics of high-dose, prolonged-infusion cefepime in adult critically ill patients with ventilator-associated pneumonia. Antimicrob Agents Chemother 2009; 53:1476-81. [PMID: 19188394 DOI: 10.1128/aac.01141-08] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A population pharmacokinetic model of cefepime was constructed from data from adult critical care patients with ventilator-associated pneumonia (VAP). A total of 32 patients treated with high-dose cefepime, 2 g every 8 h (3-h infusion) or a renal function-adjusted equivalent dose, were randomized into two groups--26 for the initial model and 6 for model validation. Serum samples of cefepime were collected at steady state. Nonparametric adaptive grid population modeling was employed using a two-compartment K(slope) pharmacokinetic model relating the elimination rate constant (K(10)) to renal function, as defined by creatinine clearance (CL(CR)), and central distribution volume (V(1)) to total body weight (TBW). The final model was described by the following equations: K(10) = 0.0027 x CL(CR) + 0.071 h(-1) and V(1) = TBW x 0.21 liter/kg. The median intercompartmental transfer constants K(12) and K(21) were 0.780 h(-1) and 0.472 h(-1), respectively. Using these median parameter estimates, the bias, precision, and coefficient of determination for the initial model were 11.3 microg/ml, 24.0 microg/ml, and 26%, respectively. The independent validation group displayed a bias, precision, and coefficient of determination of -1.64 microg/ml, 17.1 microg/ml, and 62%, respectively. Time-concentration profiles were assessed for various dosing regimens, using 5,000-patient Monte Carlo simulations. Among the regimens, the likelihoods of 2 g every 8 h (3-h infusion) achieving free drug concentrations above the MIC for 50% of the dosing interval were 91.8%, 78.1%, and 50.3% for MICs of 8, 16, and 32 microg/ml, respectively. This study provides a pharmacokinetic model capable of predicting cefepime concentrations in critically ill patients with VAP.
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Endimiani A, Perez F, Bonomo RA. Cefepime: a reappraisal in an era of increasing antimicrobial resistance. Expert Rev Anti Infect Ther 2008; 6:805-24. [PMID: 19053894 PMCID: PMC2633657 DOI: 10.1586/14787210.6.6.805] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cefepime is a 'fourth-generation' cephalosporin with an in vitro extended-spectrum of activity against Gram-negative and Gram-positive pathogens. Cefepime is approved for the treatment of moderate-to-severe infections, such as pneumonia, uncomplicated and complicated urinary tract infections, skin and soft-tissue infections, intra-abdominal infections and febrile neutropenia. In this article, we provide a critical review of pharmacodynamics, clinical management, pharmacokinetics, metabolism, pharmacodynamic target analyses, clinical efficacy, safety and tolerability of cefepime after more than a decade of clinical use.
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Affiliation(s)
- Andrea Endimiani
- Department of Medicine, Section of Infectious Diseases, Case Western Reserve University, School of Medicine, Cleveland, OH, USA.
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Alveolar concentrations of piperacillin/tazobactam administered in continuous infusion to patients with ventilator-associated pneumonia. Crit Care Med 2008; 36:1500-6. [PMID: 18434883 DOI: 10.1097/ccm.0b013e318170ba21] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To determine the steady-state serum and alveolar concentrations of piperacillin/tazobactam administered in continuous infusion to critically ill patients with ventilator-associated pneumonia and various degrees of renal failure. DESIGN Prospective comparative study. SETTING An intensive care unit and research ward in a university hospital. PATIENTS Forty patients with microbiologically documented ventilator-associated pneumonia. INTERVENTIONS Patients were randomized to receive piperacillin/tazobactam daily continuous infusions of 12/1.5 g or 16/2 g after a loading dose of 4/0.5 g. The serum and alveolar piperacillin/tazobactam concentrations were determined at steady-state with high performance liquid chromatography. MEASUREMENTS AND MAIN RESULTS The median (interquartile) serum and alveolar piperacillin concentrations were respectively 25.3 mg/L (23.1-32.6) and 12.7 mg/L (6.7-18.0) for 12/1.5 g/day, and 38.9 mg/L (32.9-59.6) and 19.1 mg/L (14.0-21.5), respectively, for 16/2 g/day in patients with no/mild renal failure. In patients with moderate/advance renal failure, the median (interquartile) serum and alveolar piperacillin concentrations were 102.4 mg/L (97.4-112.6) and 44.1 mg/L (33.4-48.3), respectively, for 12/1.5 g/day, and 135.3 mg/L (119.5-146.2) and 54.9 mg/L (45.2-110.3), respectively, for 16/2 g/day. Our results show great variability in piperacillin/tazobactam concentrations, with an alveolar percentage penetration of 40-50% for piperacillin and 65-85% for tazobactam and a negative association between serum or alveolar concentrations and creatinine clearance. CONCLUSIONS A target piperacillin serum concentration of at least 35-40 mg/L is probably required to provide alveolar concentrations exceeding the susceptibility breakpoint for gram-negative bacteria (16 mg/L) during ventilator-associated pneumonia. In patients with no/mild renal failure, a continuous daily dose of piperacillin/tazobactam 16/2 g allows reaching this target concentration, which might be not observed with 12/1.5 g/day. In patients with moderate/advanced renal failure, both dosages achieve serum concentrations far above the 35-40 mg/L threshold, suggesting that in that case, therapeutic drug monitoring should be performed in order to adjust the daily dose.
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Mimoz O, Dahyot-Fizelier C. Mini-broncho-alveolar lavage: a simple and promising method for assessment of antibiotic concentration in epithelial lining fluid. Intensive Care Med 2007; 33:1495-7. [PMID: 17594075 DOI: 10.1007/s00134-007-0689-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2007] [Accepted: 04/13/2007] [Indexed: 10/23/2022]
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Boselli E, Breilh D, Djabarouti S, Guillaume C, Rimmelé T, Gordien JB, Xuereb F, Saux MC, Allaouchiche B. Reliability of mini-bronchoalveolar lavage for the measurement of epithelial lining fluid concentrations of tobramycin in critically ill patients. Intensive Care Med 2007; 33:1519-23. [PMID: 17530217 DOI: 10.1007/s00134-007-0688-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2006] [Accepted: 04/13/2007] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To evaluate the reliability of mini-bronchoalveolar lavage (mini-BAL) for the measurement of tobramycin concentrations in epithelial lining fluid (ELF) in comparison with conventional bronchoscopic bronchoalveolar lavage (BAL). DESIGN Prospective, open-label study. SETTING An intensive care unit and research ward in a university hospital. PATIENTS Twelve critically ill adult patients with ventilator-associated pneumonia (VAP). INTERVENTIONS All subjects received intravenous infusions of tobramycin 7-10 mg/kg once daily. After 2 days of therapy, the steady-state serum and ELF concentrations (obtained from BAL and mini-BAL) of tobramycin were determined by means of high-performance liquid chromatography. MEASUREMENTS AND RESULTS We observed poor penetration of tobramycin in ELF of approximately approximately 12% with ELF peak concentrations of approximately approximately 3 mg/l with both methods. Good agreement in Bland-Altman analysis (mean +/- SD bias = 0.04 +/- 0.38 mg/l) was observed between the two methods of sampling. CONCLUSION Our results suggest that tobramycin 7-10 mg/kg once daily in critically ill patients with VAP might provide insufficient lung concentrations in the case of difficult-to-treat pathogens. Besides, mini-BAL, which is simple, non-invasive and easily repeatable at the bedside, appears to be a reliable method for the measurement of antibiotic concentrations in ELF in comparison with bronchoscopic BAL in critically ill patients with VAP.
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Affiliation(s)
- Emmanuel Boselli
- Hôpital Edouard Herriot, Department of Anesthesiology and Intensive Care, 5 place d'Arsonval, 69003 Lyon, France.
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Roberts JA, Paratz J, Paratz E, Krueger WA, Lipman J. Continuous infusion of beta-lactam antibiotics in severe infections: a review of its role. Int J Antimicrob Agents 2007; 30:11-8. [PMID: 17442541 DOI: 10.1016/j.ijantimicag.2007.02.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Revised: 01/22/2007] [Accepted: 01/23/2007] [Indexed: 01/21/2023]
Abstract
Continuous infusion of beta-lactam antibiotics has been widely promoted to optimise their time-dependent activity. Increasing evidence is emerging suggesting potential benefits in patient populations with altered pathophysiology, such as seriously ill patients. From a pharmacokinetic viewpoint, much information supports higher trough concentrations of beta-lactam antibiotics when administered by continuous infusion. This advantage of continuous infusion translates into a superior ability to achieve pharmacodynamic targets, particularly when the minimum inhibitory concentration (MIC) of the pathogen is >or=4 mg/L. One drawback of continuous infusion may be limited physicochemical stability. This issue exists particularly for carbapenem antibiotics whereby prolonged infusions (i.e. >3h) can be used to improve the time above the MIC compared with conventional bolus dosing. Few studies have examined clinical outcomes of bolus and continuous dosing of beta-lactam antibiotics in seriously ill patients. No statistically significant differences have been shown for: mortality; time to normalisation of leukocytosis or pyrexia; or duration of mechanical ventilation, intensive care unit stay or hospital stay. Some evidence suggests improved clinical cure and resolution of illness with continuous infusion in seriously ill patients. Pharmacoeconomic advantages of continuous infusion of beta-lactam antibiotics are well characterised. Available data suggest that seriously ill patients with severe infections requiring significant antibiotic courses (>or=4 days) may be the subgroup that will achieve better outcomes with continuous infusion.
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Affiliation(s)
- Jason A Roberts
- Burns Trauma and Critical Care Research Centre, University of Queensland, Brisbane, Australia
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Soy D, Torres A. Antibacterial dosage in intensive-care-unit patients based on pharmacokinetic/pharmacodynamic principles. Curr Opin Crit Care 2007; 12:477-82. [PMID: 16943729 DOI: 10.1097/01.ccx.0000244130.77365.c2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Selection of the best antibiotic dosage regimen in intensive-care-unit patients is a critical factor for decreasing morbidity and mortality rates. The integration of pharmacokinetics and pharmacodynamics is essential to establishing an adequate therapy. Many studies on this issue have been published in recent years due to its relevance, some of which are commented upon in this review. RECENT FINDINGS Several studies have shown that it is feasible to theoretically forecast pharmacodynamic outcomes and select the most adequate antibiotic therapy with Monte Carlo simulations. Moreover, new strategies such as the use of continuous or extended intravenous beta-lactam infusions may considerably improve therapeutic efficacy. SUMMARY Future studies are needed in patients to assess the influence of selecting antibiotic therapy based on the impact of pharmacokinetic/pharmacodynamic on mortality, morbidity, cost, etc. It would be of special interest to evaluate this impact on patients with infections caused by multiresistant pathogens, whose mortality rates are even higher. Moreover, although studies such as this would not be easy, mainly due to the large number of patients required to obtain statistically significant results, they should be strongly encouraged because of the possible clinical and economic benefits.
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Affiliation(s)
- Dolors Soy
- Pharmacy Service (UASP), Hospital Clinic Barcelona, IDIBAPS, Universitat de Barcelona, Spain.
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71
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Roberts JA, Webb SAR, Lipman J. Cefepime versus ceftazidime: considerations for empirical use in critically ill patients. Int J Antimicrob Agents 2006; 29:117-28. [PMID: 17158033 DOI: 10.1016/j.ijantimicag.2006.08.031] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Revised: 08/07/2006] [Accepted: 08/07/2006] [Indexed: 10/23/2022]
Abstract
Sepsis and nosocomial infections continue to be a significant problem in intensive care, contributing heavily to mortality and prolonged hospital stay. Early and appropriate antibiotic therapy is critical for optimising outcomes. However, the emergence of highly resistant bacteria, coupled with reduced development of novel antibiotics, means that there is a real threat of development of untreatable nosocomial infections. Cefepime and ceftazidime are broad-spectrum cephalosporins that are widely used to treat Gram-negative nosocomial infections in critically ill patients. Available data suggest that cefepime may have advantages over ceftazidime owing to a broader spectrum of activity and reduced potential for development of bacterial resistance. However, whether either of these agents is superior can only be determined by a head-to-head study evaluating clinical and bacteriological outcomes. Such a study to determine whether apparent differences translate into clinically relevant differences in outcome is indicated.
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Affiliation(s)
- Jason A Roberts
- Royal Brisbane and Women's Hospital, Butterfield Street, Herston, Brisbane, Qld 4029, Australia
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72
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Boselli E, Breilh D, Saux MC, Gordien JB, Allaouchiche B. Pharmacokinetics and lung concentrations of ertapenem in patients with ventilator-associated pneumonia. Intensive Care Med 2006; 32:2059-62. [PMID: 17039351 DOI: 10.1007/s00134-006-0401-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Accepted: 09/14/2006] [Indexed: 10/24/2022]
Abstract
OBJECTIVE We conducted a prospective, open-label study to determine the steady-state serum and epithelial lining fluid (ELF) concentrations of unbound ertapenem administered once daily to critically ill patients with early-onset ventilator-associated pneumonia (VAP). DESIGN AND SETTING Prospective, open-label study in an intensive care unit and research ward in a university hospital. PATIENTS Fifteen patients with VAP received 1-h intravenous infusions of 1 g ertapenem once daily. INTERVENTIONS After 2 days of therapy the steady-state serum and ELF concentrations of free ertapenem were determined by high-performance liquid chromatography. MEASUREMENTS AND RESULTS The median (interquartile range) free ertapenem peak (C(max)), intermediate (C(12)), and trough (C(min)) concentrations (mg/l) 1, 12, and 24 h after the end of infusion were 30.3 (27.1-37.8), 4.8 (3.9-6.4), and 0.8 (0.5-1.2) in serum and 9.4 (8.0-10.7), 2.0 (1.1-2.5), and 0.3 (0.2-0.4) in ELF, respectively, showing a median free ertapenem percentage penetration in ELF of approx. 30%. The median (interquartile range) serum area under concentration-time curve of free ertapenem during the observational period was 226.7 mg h(-1) l(-1) (202.2-263.9). CONCLUSION Our study shows satisfactory results, with unbound ertapenem concentrations both in serum and ELF exceeding the MIC(90) values of most of the causative pathogens encountered in early-onset VAP during 50-100% time. This suggests that 1 g intravenous ertapenem administered once daily should be effective during the treatment of early-onset VAP in critically ill patients with no known risk factors for multidrug-resistant pathogens.
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73
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López E, Soy D, Miana MT, Codina C, Ribas J. Algunas reflexiones acerca de la administración de antibióticos betalactámicos en infusión continua. Enferm Infecc Microbiol Clin 2006; 24:445-52. [PMID: 16956534 DOI: 10.1157/13091783] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Numerous studies on continuous intravenous infusion of betalactam antibiotics have indicated that this could be a useful strategy for treating nosocomial infections as well as exacerbations of pulmonary infections in patients with cystic fibrosis and episodes of febrile neutropenia. From the pharmacodynamic viewpoint, betalactam antibiotics have a time-dependent behavior. Thus, the pharmacokinetic/pharmacodynamic index that best correlates with therapeutic efficacy appears to be the time during which free antibiotic concentrations remain above the minimum inhibitory concentration (MIC) of the infecting microorganism. Continuous infusion of betalactams successfully optimizes this pharmacokinetic/ pharmacodynamic index. Furthermore, some studies have shown that this therapeutic strategy may be favorable economically.
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Affiliation(s)
- Ester López
- Servicio de Farmacia del Hospital Clínic de Barcelona. España.
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74
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Gillespie EL, Kuti JL, Nicolau DP. Pharmacodynamics of antimicrobials: treatment optimisation. Expert Opin Drug Metab Toxicol 2006; 1:351-61. [PMID: 16863448 DOI: 10.1517/17425255.1.3.351] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
As bacterial resistance continues to increase, optimising the potential for successful clinical outcomes with antimicrobial therapy requires consideration of pharmacodynamic concepts in order to maximise bacterial eradication and minimise the potential for further resistance. Based on the pharmacodynamic characteristics of specific antibiotics, dosage modifications can be implemented to improve the likelihood of bactericidal exposure. Considering their concentration-dependent bactericidal activity, aminoglycosides benefit from increased dosages and infrequent administration, so as to achieve a maximum concentration/minimum inhibitory concentration (MIC) of 10-12. In contrast, beta-lactams are concentration-independent killers and benefit greatest by increasing the time above the MIC (T > MIC). This can be accomplished with the use of prolonged or continuous infusion. By optimising pharmacodynamic parameters with these methodologies, successful treatment of pathogens may be possible in patient populations for whom standard dosing regimens are not effective.
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Affiliation(s)
- Effie L Gillespie
- Hartford Hospital, Center for AntiInfective Research and Development, 80 Seymour Street, Hartford, CT 06102, USA
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75
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Kollef MH. The intensive care unit as a research laboratory: developing strategies to prevent antimicrobial resistance. Surg Infect (Larchmt) 2006; 7:85-99. [PMID: 16629599 DOI: 10.1089/sur.2006.7.85] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE To assemble the available clinical data on the prevention of antimicrobial resistance in the intensive care unit (ICU) setting. DATA SOURCE A MEDLINE database search and references from identified articles were employed to obtain the literature relating to the prevention of antimicrobial resistance in the ICU. CONCLUSIONS The ICU presents a unique environment for the conduct of clinical research. The closed physical space with centralized patient management and efficient data recovery allows important clinical questions to be evaluated in a timely manner. Antimicrobial resistance has emerged as an important determinant of mortality for patients in the ICU. Additionally, there is currently a limited pipeline of new agents for the treatment of emerging bacteria with new resistance genes that pose an increasing threat to the ICU patient. Effective strategies for the prevention of antimicrobial resistance within ICUs are available and should be implemented aggressively. These strategies can be divided into non-pharmacologic infection- control strategies (e.g., routine hand hygiene, infection-specific prevention protocols) and antibiotic management strategies (e.g., shorter courses of appropriate antibiotics, narrowing of the antimicrobial spectrum on the basis of culture results). Additional studies conducted in ICUs are needed urgently to identify the optimal approaches for the management of antibiotics in order to balance the need for efficacy with the ability to minimize resistance.
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Affiliation(s)
- Marin H Kollef
- Pulmonary and Critical Care Division, Washington University School of Medicine, Barnes Jewish Hospital, St. Louis, Missouri 63110, USA.
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76
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Abstract
Antimicrobial resistance in the ICU is characterized by increasing overall resistance rates among gram-negative and gram-positive pathogens and increased frequency of multidrug-resistant organisms. In addition to basic principles of appropriate drug selection for empiric and definitive therapy, other specific strategies that may decrease problems of resistance through improved use of antimicrobials include appropriate application of pharmacokinetic and pharmacodynamic principles to antimicrobial use, aggressive dosing of antimicrobials, use of broad-spectrum and combination antimicrobial therapy for initial treatment, decreased duration of antimicrobial therapy, hospital formulary-based antimicrobial restrictions, use of antimicrobial protocols and guidelines, programs for restriction of target antimicrobials, scheduled antimicrobial rotation, and use of antimicrobial management programs. Combinations of various approaches may offer the best potential for effectively intervening in and reducing the spread of resistant pathogens in critically ill patients.
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Affiliation(s)
- Douglas N Fish
- Department of Clinical Pharmacy, School of Pharmacy, University of Colorado Health Sciences Center, Campus Box C-238, 4200 East Ninth Avenue, Denver, CO 80262, USA
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77
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Micek ST, Heuring TJ, Hollands JM, Shah RA, Kollef MH. Optimizing antibiotic treatment for ventilator-associated pneumonia. Pharmacotherapy 2006; 26:204-13. [PMID: 16466325 DOI: 10.1592/phco.26.2.204] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Ventilator-associated pneumonia (VAP) is the most common infectious complication in patients receiving mechanical ventilation and accounts for exorbitant use of resources in the intensive care unit. Antimicrobial management of VAP incorporates an initial broad-spectrum, empiric regimen to ensure appropriate coverage with deescalation of therapy after 48-72 hours based on culture results and sensitivities. When VAP clinically responds to treatment, antimicrobials should be discontinued after 7-8 days to reduce overall antibiotic consumption and the selection pressure on flora observed in the intensive care unit and thus minimize the development and spread of antimicrobial resistance.
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Affiliation(s)
- Scott T Micek
- Department of Pharmacy, Barnes-Jewish Hospital, St. Louis, Missouri 63110, USA.
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78
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Mimoz O, Rolland D, Adoun M, Marchand S, Breilh D, Brumpt I, Debaene B, Couet W. Steady-state trough serum and epithelial lining fluid concentrations of teicoplanin 12 mg/kg per day in patients with ventilator-associated pneumonia. Intensive Care Med 2006; 32:775-9. [PMID: 16550370 DOI: 10.1007/s00134-006-0136-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2005] [Accepted: 02/23/2006] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To determine the steady-state trough serum and epithelial lining fluid (ELF) concentrations of teicoplanin 12 mg/kg per day in critically ill patients with ventilator associated pneumonia. DESIGN AND SETTING Prospective, pharmacokinetic study in the surgical intensive care unit in a university hospital. PATIENTS Thirteen adult patients with nosocomial bacterial pneumonia on mechanical ventilation were enrolled. INTERVENTIONS All subjects received a 30-min intravenous infusion of 12 mg/kg teicoplanin every 12 h for 2 consecutive days followed by 12 mg/kg once daily. Teicoplanin concentrations in serum and ELF were determined simultaneously 4-6 days after antibiotic administration started. MEASUREMENTS AND RESULTS The median total and free concentrations of teicoplanin in serum at trough were 15.9 microg/ml (range 8.8-29.9) and 3.7 (2.0-5.4), respectively. The concentration in ELF was 4.9 (2.0-11.8). CONCLUSIONS In critically ill patients with ventilator-associated pneumonia the administration of high teicoplanin doses is required to reach sufficient trough antibiotic concentrations in lung tissues at steady state. At that time trough-free concentrations of teicoplanin in serum and ELF are comparable.
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Affiliation(s)
- Olivier Mimoz
- Département d'Anesthésie et Réanimation Chirurgicale, Centre Hospitalier et Universitaire de Poitiers, Poitiers, France.
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79
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Kasiakou SK, Lawrence KR, Choulis N, Falagas ME. Continuous versus intermittent intravenous administration of antibacterials with time-dependent action: a systematic review of pharmacokinetic and pharmacodynamic parameters. Drugs 2006; 65:2499-511. [PMID: 16296874 DOI: 10.2165/00003495-200565170-00006] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We performed a systematic review of randomised clinical trials to evaluate the comparative pharmacokinetic and pharmacodynamic properties of the continuous versus intermittent mode of intravenous administration of various antibacterials. Data were identified from PubMed (January 1950 to January 2005), Current Contents, the Cochrane central register of controlled trials, and references from relevant articles and reviews. Seventeen randomised clinical trials comparing continuous with intermittent intravenous administration of the same antibacterial regimen and examining the pharmacokinetic and pharmacodynamic properties were included in this systematic review. We reviewed data regarding the clinical setting, number of participants, antibacterial agents and dosages used, as well as maximum serum concentration (Cmax), trough serum concentration (Cmin), steady-state or plateau serum concentration (Css), area under the concentration-time curve (AUC), time above the minimum inhibitory concentration (MIC) [T>MIC], AUC: MIC, elimination rate constant, elimination half-life, volume of distribution and systematic clearance. The mean Cmax of the intermittently administered antibacterials was higher compared with Css achieved by the continuous infusion of the same antibacterial in all eligible studies (Cmax was on average 5.5 times higher than Css, range 1.9-11.2). Css was on average 5.8 times higher than the Cmin of the intermittently administered antibacterials (range 1.2-15.6). In three of six studies the length of time that the drug concentration was above the MIC of the responsible pathogens was longer in patients receiving the antibacterials continuously. In conclusion, the reviewed data suggest that the continuous intravenous infusion of antibacterials with time-dependent bacterial killing seems to be superior than the intermittent intravenous administration, from a pharmacodynamic point of view, at least when treating bacteria with high MIC values for the studied antibacterials.
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Affiliation(s)
- Sofia K Kasiakou
- Alfa Institute of Biomedical Sciences (AIBS), and Alfa HealthCare, Athens, Greece
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80
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Munckhof WJ, Carney J, Neilson G, Neilson J, Carroll J, McWhinney B, Whitby M. Continuous infusion of ticarcillin-clavulanate for home treatment of serious infections: clinical efficacy, safety, pharmacokinetics and pharmacodynamics. Int J Antimicrob Agents 2005; 25:514-22. [PMID: 15878264 DOI: 10.1016/j.ijantimicag.2005.02.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2004] [Accepted: 02/18/2005] [Indexed: 11/30/2022]
Abstract
Continuous infusion (CI) ticarcillin-clavulanate is a potential therapeutic improvement over conventional intermittent dosing because the major pharmacodynamic (PD) predictor of efficacy of beta-lactams is the time that free drug levels exceed the MIC. This study incorporated a 6-year retrospective arm evaluating efficacy and safety of CI ticarcillin-clavulanate in the home treatment of serious infections and a prospective arm additionally evaluating pharmacokinetics (PK) and PD. In the prospective arm, steady-state serum ticarcillin and clavulanate levels and MIC testing of significant pathogens were performed. One hundred and twelve patients (median age, 56 years) were treated with a CI dose of 9.3-12.4g/day and mean CI duration of 18.0 days. Infections treated included osteomyelitis (50 patients), septic arthritis (6), cellulitis (17), pulmonary infections (12), febrile neutropenia (7), vascular infections (7), intra-abdominal infections (2), and Gram-negative endocarditis (2); 91/112 (81%) of patients were cured, 14 (13%) had partial response and 7 (6%) failed therapy. Nine patients had PICC line complications and five patients had drug adverse events. Eighteen patients had prospective PK/PD assessment although only four patients had sufficient data for a full PK/PD evaluation (both serum steady-state drug levels and ticarcillin and clavulanate MICs from a bacteriological isolate), as this was difficult to obtain in home-based patients, particularly as serum clavulanate levels were found to deteriorate rapidly on storage. Three of four patients with matched PK/PD assessment had free drug levels exceeding the MIC of the pathogen. Home CI of ticarcillin-clavulanate is a safe, effective, convenient and practical therapy and is a therapeutic advance over traditional intermittent dosing when used in the home setting.
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Affiliation(s)
- Wendy J Munckhof
- Infection Management Services, Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Brisbane, QLD 4102, Australia.
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81
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Abstract
OBJECTIVE To assemble the available clinical data for the prevention of antimicrobial resistance into practical recommendations for clinicians. DATA SOURCE A Medline database and references from identified articles were employed to perform a literature search relating to the prevention of antimicrobial resistance. CONCLUSIONS Antimicrobial resistance has emerged as an important determinant of mortality for patients in the intensive care unit. This is largely due to the increasing presence of pathogenic microorganisms with resistance to existing antimicrobial agents, resulting in the administration of inappropriate treatment. Effective strategies for the prevention of antimicrobial resistance within intensive care units are available and should be aggressively implemented. These strategies can be divided into nonpharmacologic infection control strategies (e.g., routine hand hygiene, implementation of infection-specific prevention protocols) and antibiotic management strategies (e.g., shorter courses of appropriate antibiotic treatment, narrowing of antimicrobial spectrum based on culture results). Increasing current efforts aimed at the prevention of antimicrobial resistance is especially important given the limited availability of new antimicrobial drug classes for the foreseeable future.
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Affiliation(s)
- Marin H Kollef
- Department of Internal Medicine, Pulmonary and Critical Care Division, Washington University School of Medicine, St. Louis, MO 63110, USA.
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82
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Kasiakou SK, Sermaides GJ, Michalopoulos A, Soteriades ES, Falagas ME. Continuous versus intermittent intravenous administration of antibiotics: a meta-analysis of randomised controlled trials. THE LANCET. INFECTIOUS DISEASES 2005; 5:581-9. [PMID: 16122681 DOI: 10.1016/s1473-3099(05)70218-8] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Intermittent intravenous administration of antibiotics is the first-line approach in the management of severe infections worldwide. However, the potential benefits of alternate modes of administration of antibiotics, including continuous intravenous infusion, deserve further evaluation. We did a meta-analysis of randomised controlled trials comparing continuous intravenous infusion with intermittent intravenous administration of the same antibiotic regimen. Nine randomised controlled trials studying beta-lactams, aminoglycosides, and vancomycin were included. Clinical failure was lower, although without statistical significance, in patients receiving continuous infusion of antibiotics (pooled OR 0.73, 95% CI 0.53-1.01); the difference was statistically significant in a subset of randomised controlled trials that used the same total daily antibiotic dose for both intervention arms (0.70, 0.50-0.98, fixed and random effects models). Regarding mortality and nephrotoxicity, no differences were found (mortality 0.89, 0.48-1.64; nephrotoxicity 0.91, 0.56-1.47). In conclusion, the data suggest that the administration of the same total antibiotic dose by continuous intravenous infusion may be more efficient, with regard to clinical effectiveness, compared with the intermittent mode. In an era of gradually increasing resistance among most pathogens, the potential advantages of continuous intravenous administration of antibiotics on several clinical outcomes should be further investigated.
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83
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Boselli E, Breilh D, Rimmelé T, Djabarouti S, Toutain J, Chassard D, Saux MC, Allaouchiche B. Pharmacokinetics and intrapulmonary concentrations of linezolid administered to critically ill patients with ventilator-associated pneumonia. Crit Care Med 2005; 33:1529-33. [PMID: 16003058 DOI: 10.1097/01.ccm.0000168206.59873.80] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To determine the steady-state plasma pharmacokinetic variables and epithelial lining fluid concentrations of linezolid administered to critically ill patients with ventilator-associated pneumonia. DESIGN Prospective, open-label study. SETTING An intensive care unit and research ward in a university hospital. PATIENTS Sixteen critically ill adult patients with ventilator-associated pneumonia. INTERVENTIONS All subjects received 1-hr intravenous infusions of linezolid 600 mg twice daily. After 2 days of therapy, the steady-state plasma pharmacokinetic variables and epithelial lining fluid concentrations of linezolid were determined by high-performance liquid chromatography. MEASUREMENTS AND MAIN RESULTS The mean +/- sd linezolid peak and trough concentrations were 17.7 +/- 4.0 mg/L and 2.4 +/- 1.2 mg/L in plasma and 14.4 +/- 5.6 mg/L and 2.6 +/- 1.7 mg/L in epithelial lining fluid, respectively, showing a mean linezolid percentage penetration in epithelial lining fluid of approximately 100%. The mean +/- sd area under concentration-time curve during the observational period (AUC0-12) was 77.3 +/- 23.7 mg x hr/L, corresponding to a mean AUC0-24 of 154.6 mg x hr/L. CONCLUSIONS Our study shows satisfactory results, with linezolid concentrations exceeding the susceptibility breakpoint for Gram-positive bacteria in both plasma and epithelial lining fluid. This suggests that a dosage of 600 mg administered intravenously twice daily to critically ill patients with Gram-positive ventilator-associated pneumonia would achieve success against organisms with minimum inhibitory concentrations as high as 2-4 mg/L in both plasma and epithelial lining fluid.
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Affiliation(s)
- Emmanuel Boselli
- Department of Anesthesiology and Intensive Care, Edouard Herriot Hospital, Lyon, France
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84
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Kollef MH. Bench-to-bedside review: antimicrobial utilization strategies aimed at preventing the emergence of bacterial resistance in the intensive care unit. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2005; 9:459-64. [PMID: 16277734 PMCID: PMC1297604 DOI: 10.1186/cc3757] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Antimicrobial resistance has emerged as one of the most important issues complicating the management of critically ill patients with infection. This is largely due to the increasing presence of pathogenic microorganisms with resistance to existing antimicrobial agents resulting in the administration of inappropriate treatment. Effective strategies for the prevention of antimicrobial resistance within intensive care units are available and should be aggressively implemented. The importance of preventing antimicrobial resistance is magnified by the limited availability of new antimicrobial drug classes for the foreseeable future.
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Affiliation(s)
- Marin H Kollef
- Department of Internal Medicine, Pulmonary and Critical Care Division, Washington University School of Medicine, St Louis, Missouri, USA.
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85
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Charles PE, Etienne M, Croisier D, Piroth L, Lequeu C, Pugin J, Portier H, Chavanet P. The impact of mechanical ventilation on the moxifloxacin treatment of experimental pneumonia caused by Streptococcus pneumoniae. Crit Care Med 2005; 33:1029-35. [PMID: 15891332 DOI: 10.1097/01.ccm.0000163404.35338.72] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
OBJECTIVE Streptococcus pneumoniae is a leading cause of community-acquired pneumonia and is responsible for early-onset ventilator-associated pneumonia as well. In intensive care units, community-acquired pneumonia is still associated with a mortality rate of up to 30%, especially when mechanical ventilation is required. Our objective was to study to what extent MV could influence the efficacy of moxifloxacin in a rabbit model of pneumonia. DESIGN Prospective experimental study. SETTING University hospital laboratory. SUBJECTS Male New Zealand White rabbits (n = 75). INTERVENTIONS S. pneumoniae (16089 strain; minimal inhibitory concentration for moxifloxacin = 0.125 mg/L) was instilled intrabronchially. Four hours later, a human-like moxifloxacin treatment was initiated in spontaneously breathing (SB) and mechanically ventilated (MV) animals. Untreated rabbits were used as controls. Survivors were killed 48 hrs later. Pneumonia was assessed and moxifloxacin pharmacokinetics were analyzed. MEASUREMENTS AND MAIN RESULTS Moxifloxacin treatment was associated with an improvement in survival in the SB animals (13 of 13 [100%] vs. eight of 37 [21.6%] controls). The survival rate was less influenced by treatment in MV rabbits (seven of 15 [46.1%] vs. one of eight [12.5%] controls). The lung bacterial burden was greater in MV compared with SB rabbits (5.1 +/- 2.4 vs. 1.6 +/- 1.4 log10 colony-forming units/g, respectively). Nearly all the untreated animals presented bacteremia as reflected by a positive spleen culture. No bacteremia was found in SB animals treated with moxifloxacin. In contrast, three of 13 (23.1%) moxifloxacin-treated and MV animals had positive spleen cultures. The apparent volume of distribution of moxifloxacin was lower in MV compared with SB rabbits. CONCLUSIONS In our model of moxifloxacin-treated S. pneumoniae pneumonia, mechanical ventilation was associated with a higher mortality rate and seemed to promote bacterial growth as well as systemic spread of the infection. In addition, the volume of distribution of moxifloxacin was reduced in the presence of mechanical ventilation. Although the roles of factors such as anesthesia, paralysis, and endotracheal tube insertion could not be established, these results suggest that mechanical ventilation may impair host lung defense, rendering antibiotic therapy less effective.
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86
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Michel MC, de la Rosette JJMCH. Efficacy and safety of tamsulosin in the treatment of urological diseases. Expert Opin Pharmacother 2005; 5:151-60. [PMID: 14680444 DOI: 10.1517/14656566.5.1.151] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The alpha(1)-adrenoceptor antagonist, tamsulosin, is selective for alpha(1A)- and alpha(1D)- over alpha(1B)-adrenoceptors. Both placebo-controlled and comparative studies with other agents have demonstrated tamsulosin to be an effective treatment for patients with lower urinary symptoms suggestive of benign prostatic hyperplasia. Its effectiveness appears to be maintained over many years. Tamsulosin may also effectively reduce lower urinary tract symptoms in other urological diseases. A dose of tamsulosin 0.4 mg/day has a tolerability close to that of placebo and has little, if any, blood pressure lowering effects. Tolerability and lack of blood pressure lowering are maintained even in high-risk patients such as those with cardiovascular comorbidity and/or comedication. Apart from adrenoceptor subtype-selectivity, a smooth pharmacokinetic profile of its modified-release formulation and a selective accumulation in target tissues may contribute to an excellent efficacy:tolerability ratio.
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Affiliation(s)
- Martin C Michel
- Department of Pharmacology, and Pharmacotherapy, University of Amsterdam, The Netherlands.
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87
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Boselli E, Breilh D, Rimmelé T, Djabarouti S, Saux MC, Chassard D, Allaouchiche B. Pharmacokinetics and intrapulmonary diffusion of levofloxacin in critically ill patients with severe community-acquired pneumonia. Crit Care Med 2005; 33:104-9. [PMID: 15644655 DOI: 10.1097/01.ccm.0000150265.42067.4c] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To determine the steady-state plasma and epithelial lining fluid concentrations of intravenous levofloxacin, 500 mg, administered once or twice daily in critically ill patients with severe community-acquired pneumonia. DESIGN Prospective, open-label study. SETTING An intensive care unit and a clinical pharmacokinetic laboratory in two university hospitals. PATIENTS Twenty-four adult patients with severe community-acquired pneumonia and receiving mechanical ventilation were enrolled. INTERVENTIONS All subjects received 1-hr intravenous infusions of 500 mg levofloxacin once or twice daily. The plasma and epithelial lining fluid levofloxacin concentrations were determined at steady-state after 2 days of therapy with high-performance liquid chromatography. MEASUREMENTS AND MAIN RESULTS The median (interquartile range [IQR]) plasma and epithelial lining fluid peak levofloxacin concentrations were 12.6 (IQR, 12.0-14.1) and 11.9 (IQR, 8.7-13.7) mg/L, respectively, in the once-daily group and 19.7 (IQR, 19.0-22.0) and 17.8 (IQR, 16.2-23.5) mg/L in the twice-daily group, showing a pulmonary percentage penetration of >100% in both groups. The median (IQR) total body exposures were 151 (IQR, 137-174) and 416 (IQR, 406-472) mg.hr/L, respectively, in the once-daily and twice-daily groups. CONCLUSIONS Our results suggest that in critically ill patients who are receiving mechanical ventilation and have severe community-acquired pneumonia and creatinine clearance of >40 mL/min, the administration of 500 mg of intravenous levofloxacin once and twice daily allows for the exceeding of pharmacodynamic thresholds predictive of outcome (i.e., peak concentration to minimum inhibitory concentration ratio of >10 or area under concentration-time curve to minimal inhibitory concentration ratio of >125 hrs) both in serum and epithelial lining fluid for pathogens with minimum inhibitory concentration values of < or =1 mg/L and >1 mg/L, respectively.
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Affiliation(s)
- Emmanuel Boselli
- Department of Anesthesiology and Intensive Care, Hôtel-Dieu Hospital, Lyon, France
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Kollef MH. The importance of antimicrobial resistance in hospital-acquired and ventilator-associated pneumonia. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.cacc.2005.11.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Intrapulmonary Concentrations of Cefepime: The authors reply. Crit Care Med 2004. [DOI: 10.1097/01.ccm.0000126378.67582.80] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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De Rosa FG, Zeme D, Bargiacchi O, Audagnotto S, Bonora S, Di Perri G. Intrapulmonary Concentrations of Cefepime. Crit Care Med 2004; 32:1238; author reply 1238-9. [PMID: 15190988 DOI: 10.1097/01.ccm.0000115254.81488.f8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
For an antibiotic to be active in vivo, the concept of high tissue concentrations at infected sites has been popular for a long time, but has recently been criticised. The measurement of antibiotic tissue levels in humans is restricted by ethical issues, the cost of investigations and doubtful clinical significance. In the respiratory tree (RT), antibiotic concentrations have been studied. It has been shown that the antibiotic concentrations in both the lung tissue and fluids are related to three factors: the frequency of community and severe hospital respiratory infections; the wide prescription of antibiotics in cases of respiratory infections; and the easy access of sampling different areas of the RT. Due to the controversial perception of these studies, new pharmacological approaches have been developed using animal models, in vitro simulation of antibiotic kinetics in human serum and the involvement of pathogens, thus resulting in new pharmacodynamic parameters. This review looks at the concepts in antibiotic concentrations and the pharmacodynamics of the RT.
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Boselli E, Breilh D, Cannesson M, Xuereb F, Rimmelé T, Chassard D, Saux MC, Allaouchiche B. Steady-state plasma and intrapulmonary concentrations of piperacillin/tazobactam 4 g/0.5 g administered to critically ill patients with severe nosocomial pneumonia. Intensive Care Med 2004; 30:976-9. [PMID: 15057512 DOI: 10.1007/s00134-004-2222-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2003] [Accepted: 01/29/2004] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To determine the steady-state plasma and epithelial lining fluid (ELF) concentrations of piperacillin/tazobactam (P/T) administered to critically ill patients with severe bacterial pneumonia. DESIGN Prospective, open-label study. SETTING An intensive care unit and research ward in a university hospital. PATIENTS Ten adult patients with severe nosocomial bacterial pneumonia on mechanical ventilation. INTERVENTIONS All subjects received a 30-min intravenous infusion of P/T 4 g/0.5 g every 8 h. The steady-state plasma and ELF concentrations of P/T were determined by high-performance liquid chromatography. MEASUREMENTS AND MAIN RESULTS The mean+/-SD steady-state plasma trough, peak, and intermediate concentrations were 8.5+/-4.6 microg/ml, 55.9+/-21.6 microg/ml, and 24.0+/-13.8 microg/ml for piperacillin, and 2.1+/-1.0 microg/ml, 4.8+/-2.1 microg/ml, and 2.4+/-1.2 microg/ml for tazobactam, respectively. The mean+/-SD steady-state intermediate ELF concentrations were 13.6+/-9.4 microg/ml for piperacillin and 2.1+/-1.1 microg/ml for tazobactam, respectively, showing a mean percentage penetration of piperacillin and tazobactam into ELF of 56.8% and 91.3 %, respectively, with a P/T ratio of 6.5:1. CONCLUSION Our results show that during the treatment of severe nosocomial pneumonia, a regimen of P/T 4 g/0.5 g every 8 h might provide insufficient concentrations into lung tissue to exceed the MIC of many causative pathogens. This suggests that higher doses of P/T should be administered in order to maximize the antibiotic concentration at the site of infection, or that a second antimicrobial agent should be used in association.
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Affiliation(s)
- Emmanuel Boselli
- Department of Anesthesiology and Intensive Care, Hôtel-Dieu, 1 Place de l'Hôpital, 69288 Lyon Cedex 02, France.
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Boselli E, Breilh D, Rimmelé T, Poupelin JC, Saux MC, Chassard D, Allaouchiche B. Plasma and lung concentrations of ceftazidime administered in continuous infusion to critically ill patients with severe nosocomial pneumonia. Intensive Care Med 2004; 30:989-91. [PMID: 14985960 DOI: 10.1007/s00134-004-2171-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2003] [Accepted: 12/31/2003] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To determine the steady-state plasma and epithelial lining fluid (ELF) concentrations of ceftazidime administered in continuous infusion to critically ill patients with severe nosocomial pneumonia. DESIGN Prospective, open-label study. SETTING An intensive care unit and research ward in a university hospital. PATIENTS A total of 15 adult patients with severe nosocomial bacterial pneumonia on mechanical ventilation were enrolled. INTERVENTIONS All subjects received a 30 min intravenous infusion of 2 g ceftazidime followed by a continuous infusion of 4 g over 24 h. The concentrations of ceftazidime in plasma and ELF were determined at steady-state after 2 days of therapy by high performance liquid chromatography. MEASUREMENTS AND MAIN RESULTS The mean +/-SD steady-state plasma and ELF concentrations of 4 g ceftazidime in continuous infusion were 39.6+/-15.2 microg/mL and 8.2+/-4.8 microg/mL, respectively, showing a mean +/-SD percentage penetration of ceftazidime into ELF of 20.6+/-8.9%. CONCLUSION The administration of 4 g ceftazidime in continuous infusion in critically ill patients with severe nosocomial pneumonia provides concentrations in excess of the minimal inhibitory concentration of many susceptible organisms over the course of therapy both in serum and ELF. However, for some pathogens such as P. aeruginosa, higher doses of ceftazidime should be administered, or another agent should be used in combination.
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Affiliation(s)
- Emmanuel Boselli
- Department of Anesthesiology and Intensive Care, Hôtel-Dieu, 1 Place de l'Hôpital, 69288 Lyon cedex 02, France.
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