Antimicrobial dosing in acute renal replacement

Vancomycin removal and pharmacokinetics during accelerated venovenous hemofiltration

INTRODUCTION

Vancomycin pharmacokinetics are affected by renal replacement therapy and physiologic changes in critically ill patients. Literature regarding vancomycin removal and pharmacokinetics during accelerated venovenous hemofiltration (AVVH), a form of prolonged intermittent renal replacement therapy, is limited.

OBJECTIVE

To describe the removal and pharmacokinetics of vancomycin during AVVH.

METHODS

Eighteen critically ill adults receiving vancomycin and AVVH were included. Vancomycin serum concentrations were obtained within 4 h before and 2-6 h after the AVVH session. Patients' serum concentrations were plotted against time, and individual pharmacokinetic parameters were determined by a one-compartmental analysis. Continuous data are reported as a median (interquartile range [IQR]) and categorical data as a percentage.

RESULTS

The median AVVH effluent rate was 39.3 mL/kg/h (IQR 35.5-48 mL/kg/h) for a duration of 9 h (IQR 8-9.75 h). AVVH decreased vancomycin concentrations by 29.8% (IQR 24.9%-35.9%), at a rate of 3.4% per hour (IQR 3.1%-4.3% per hour) of AVVH. The vancomycin elimination rate constant and half-life were 0.039 h-1 (IQR 0.036-0.053 h-1 ) and 17.6 h (IQR 13.1-18.8 h), respectively. The area under the curve during AVVH was 171.7 mg*h/L (IQR 149.1-190 mg*h/L). The volume of distribution in 10 patients was 1 L/kg (IQR 0.73-1.1 L/kg). After AVVH, vancomycin 1000 mg (IQR 750-1000 mg) was needed to maintain a serum trough concentration ≥15 mg/L.

CONCLUSION

Vancomycin is significantly removed by AVVH, which requires supplemental dosing after completion of the AVVH session to maintain desired serum concentrations. Therapeutic drug monitoring of vancomycin serum concentrations is recommended for patients undergoing AVVH.

Antibiotic Stewardship and Therapeutic Drug Monitoring of β-Lactam Antibiotics: Is There a Link? An Opinion Paper

PURPOSE

In critically ill patients, changes in the pharmacokinetics (PK) of β-lactams can lead to significant variations in serum concentrations, with possibly detrimental effects on outcomes. The utilization of individually calculated doses, extended infusion regimen, and therapeutic drug monitoring (TDM)-guided dose adjustments can mitigate the PK changes and help to achieve and attain an individual PK target.

METHODS

We reviewed relevant literature from 2004 to 2021 using 4 search engines (PubMed, Web of Science, Scopus, and Google Scholar). Unpublished clinical data were also examined.

RESULTS

TDM-guided, individualized dosing strategies facilitated PK target attainment and improved patient outcomes. TDM-guided therapy is a core concept of individualized dosing that increases PK target attainment and identifies possible toxic β-lactam concentrations.

CONCLUSIONS

Individualized dosing and TDM facilitate the rational use of β-lactams and are integral for antibiotic stewardship interventions in critical care, affording the optimal exposure of both pathogen and drugs, along with enhanced treatment efficacy and reduced emergence of antimicrobial resistance.

Therapeutic Drug Monitoring of Antibiotic Drugs in Patients Receiving Continuous Renal Replacement Therapy or Intermittent Hemodialysis: A Critical Review

PURPOSE

Antibiotics are frequently used in patients receiving intermittent or continuous renal replacement therapy (RRT). Continuous renal replacement may alter the pharmacokinetics (PK) and the ability to achieve PK/pharmacodynamic (PD) targets. Therapeutic drug monitoring (TDM) could help evaluate drug exposure and guide antibiotic dosage adjustment. The present review describes recent TDM data on antibiotic exposure and PK/PD target attainment (TA) in patients receiving intermittent or continuous RRT, proposing practical guidelines for performing TDM.

METHODS

Studies on antibiotic TDM performed in patients receiving intermittent or continuous RRT published between 2000 and 2020 were searched and assessed. The authors focused on studies that reported data on PK/PD TA. TDM recommendations were based on clinically relevant PK/PD relationships and previously published guidelines.

RESULTS

In total, 2383 reports were retrieved. After excluding nonrelevant publications, 139 articles were selected. Overall, 107 studies reported PK/PD TA for 24 agents. Data were available for various intermittent and continuous RRT techniques. The study design, TDM practice, and definition of PK/PD targets were inconsistent across studies. Drug exposure and TA rates were highly variable. TDM seems to be necessary to control drug exposure in patients receiving intermittent and continuous RRT techniques, especially for antibiotics with narrow therapeutic margins and in critically ill patients. Practical recommendations can provide insights on relevant PK/PD targets, sampling, and timing of TDM for various antibiotic classes.

CONCLUSIONS

Highly variable antibiotic exposure and TA have been reported in patients receiving intermittent or continuous RRT. TDM for aminoglycosides, beta-lactams, glycopeptides, linezolid, and colistin is recommended in patients receiving RRT and suggested for daptomycin, fluoroquinolones, and tigecycline in critically ill patients on RRT.

Nephrologist Interventions to Avoid Kidney Replacement Therapy in Acute Kidney Injury

BACKGROUND

Based on the pathophysiology of acute kidney injury (AKI), it is plausible that certain early interventions by the nephrologist could influence its trajectory. In this study, we investigated the impact of 5 early nephrology interventions on starting kidney replacement therapy (KRT), AKI progression, and death.

METHODS

In a prospective cohort at the Hospital Civil of Guadalajara, we followed up for 10 days AKI patients in whom a nephrology consultation was requested. We analyzed 5 early interventions of the nephrology team (fluid adjustment, nephrotoxic withdrawal, antibiotic dose adjustment, nutritional adjustment, and removal of hyperchloremic solutions) after the propensity score and multivariate analysis for the risk of starting KRT (primary objective), AKI progression to stage 3, and death (secondary objectives).

RESULTS

From 2017 to 2020, we analyzed 288 AKI patients. The mean age was 55.3 years, 60.7% were male, AKI KDIGO stage 3 was present in 50.5% of them, sepsis was the main etiology 50.3%, and 72 (25%) patients started KRT. The overall survival was 84.4%. Fluid adjustment was the only intervention associated with a decreased risk for starting KRT (odds ratio [OR]: 0.58, 95% confidence interval [CI]: 0.48-0.70, and p ≤ 0.001) and AKI progression to stage 3 (OR: 0.59, 95% CI: 0.49-0.71, and p ≤ 0.001). Receiving vasopressors and KRT were associated with mortality. None of the interventions studied was associated with reducing the risk of death.

CONCLUSIONS

In this prospective cohort study of AKI patients, we found for the first time that early nephrologist intervention and fluid prescription adjustment were associated with lower risk of starting KRT and progression to AKI stage 3.

Optimizing ceftaroline dosing in critically ill patients undergoing continuous renal replacement therapy

BACKGROUND AND OBJECTIVES

Currently, no dosing information exists for ceftaroline fosamil in patients undergoing continuous renal replacement therapy (CRRT). The objectives of this study are to characterize the pharmacokinetics of ceftaroline in critically ill patients undergoing CRRT modalities and to derive individualized dosing recommendations.

METHODS

This pharmacokinetic study aimed to enroll critically ill patients receiving ceftaroline fosamil and any CRRT modality from adult intensive care units. Selection of the specific CRRT modality and dosing regimen was based on clinical discretion. Pre-filter, post-filter, and ultrafiltrate samples were obtained before the administration of the fourth dose, after the completion of the infusion, and up to five additional time points post-infusion. Plasma concentrations were measured using a validated ultra-high performance liquid chromatography assay. Individual pharmacokinetic parameters were calculated using non-compartmental analysis.

RESULTS

Four patients were enrolled to investigate the need for dosing adjustments. The average sieving coefficient for ceftaroline was 0.81 ± 0.1, indicating high filter efficiency. The average volume of distribution was 41.8 L (0.48 L/kg) and is within the previously reported range in patients with normal renal function. Non-renal clearance accounted for more than 50% of the total clearance observed in patients. The observed pharmacokinetic profiles suggest that the pharmacodynamic target for 2-log10  CFU reduction from baseline (%fT >1 mg/L of 50%) was met for each patient. Due to the impact of CRRT and non-renal clearance, dosing recommendations were derived for different ranges of effluent flow rates and adjusted body weights. For a patient with an adjusted body weight of 70 kg and receiving CRRT at an effluent flow rate of 3 L/h, a ceftaroline fosamil dosing regimen of 400 mg every 12 h is proposed.

CONCLUSION

Ceftaroline is cleared extensively in critically ill patients receiving CRRT and may impact pharmacodynamic target achievement. Dose adjustments should be based on the intensity of the CRRT regimen, patient weight, and the clinical status of the patient.

What Are the Current Approaches to Optimising Antimicrobial Dosing in the Intensive Care Unit?

Antimicrobial dosing in the intensive care unit (ICU) can be problematic due to various challenges including unique physiological changes observed in critically ill patients and the presence of pathogens with reduced susceptibility. These challenges result in reduced likelihood of standard antimicrobial dosing regimens achieving target exposures associated with optimal patient outcomes. Therefore, the aim of this review is to explore the various methods for optimisation of antimicrobial dosing in ICU patients. Dosing nomograms developed from pharmacokinetic/statistical models and therapeutic drug monitoring are commonly used. However, recent advances in mathematical and statistical modelling have resulted in the development of novel dosing software that utilise Bayesian forecasting and/or artificial intelligence. These programs utilise therapeutic drug monitoring results to further personalise antimicrobial therapy based on each patient’s clinical characteristics. Studies quantifying the clinical and cost benefits associated with dosing software are required before widespread use as a point-of-care system can be justified.

Pharmacokinetics and Pharmacodynamics of Anti-infective Agents during Continuous Veno-venous Hemofiltration in Critically Ill Patients: Lessons Learned from an Ancillary Study of the IVOIRE Trial

Background

Hemofiltration rate, changes in blood and ultrafiltration flow, and discrepancies between the prescribed and administered doses strongly influence pharmacokinetics (PK) and pharmacodynamics (PD) of antimicrobial agents during continuous veno-venous hemofiltration (CVVH) in critically ill patients.

Methods

Ancillary data were from the prospective multicenter IVOIRE (hIgh VOlume in Intensive caRE) study. High volume (HV, 70 mL/kg/h) was at random compared with standard volume (SV, 35 mL/kg/h) CVVH in septic shock patients with acute kidney injury (AKI). PK/PD parameters for all antimicrobial agents used in each patient were studied during five days.

Results

Antimicrobial treatment met efficacy targets for both percentage of time above the minimal inhibitory concentration and inhibitory quotient. A significant correlation was observed between the ultrafiltration flow and total systemic clearance (Spearman test: P < 0.005) and between CVVH clearance and drug elimination half-life (Spearman test: P < 0.005). All agents were easily filtered. Mean sieving coefficient ranged from 38.7% to 96.7%. Mean elimination half-life of all agents was significantly shorter during HV-CVVH (from 1.29 to 28.54 h) than during SV-CVVH (from 1.51 to 33.85 h) (P < 0.05).

Conclusions

This study confirms that CVVH influences the PK/PD behavior of most antimicrobial agents. Antimicrobial elimination was directly correlated with convection rate. Current antimicrobial dose recommendations will expose patients to underdosing and increase the risk for treatment failure and development of resistance. Dose recommendations are proposed for some major antibiotic and antifungal treatments in patients receiving at least 25 mL/kg/h CVVH.

Basic Principles of Antibiotics Dosing in Patients with Sepsis and Acute Kidney Damage Treated with Continuous Venovenous Hemodiafiltration

Sepsis is the leading cause of acute kidney damage in patients in intensive care units. Pathophysiological mechanisms of the development of acute kidney damage in patients with sepsis may be hemodynamic and non-hemodynamic. Patients with severe sepsis, septic shock and acute kidney damage are treated with continuous venovenous hemodiafiltration. Sepsis, acute kidney damage, and continuous venovenous hemodiafiltration have a significant effect on the pharmacokinetics and pharmacodynamics of antibiotics. The impact dose of antibiotics is increased due to the increased volume of distribution (increased administration of crystalloids, hypoalbuminemia, increased capillary permeability syndrome toproteins). The dose of antibiotic maintenance depends on renal, non-renal and extracorporeal clearance. In the early stage of sepsis, there is an increased renal clearance of antibiotics, caused by glomerular hyperfiltration, while in the late stage of sepsis, as the consequence of the development of acute renal damage, renal clearance of antibiotics is reduced. The extracorporeal clearance of antibiotics depends on the hydrosolubility and pharmacokinetic characteristics of the antibiotic, but also on the type of continuous dialysis modality, dialysis dose, membrane type, blood flow rate, dialysis flow rate, net filtration rate, and effluent flow rate. Early detection of sepsis and acute kidney damage, early target therapy, early administration of antibiotics at an appropriate dose, and early extracorporeal therapy for kidney replacement and removal of the inflammatory mediators can improve the outcome of patients with sepsis in intensive care units.

Pharmacokinetics-pharmacodynamics issues relevant for the clinical use of beta-lactam antibiotics in critically ill patients

Antimicrobials are among the most important and commonly prescribed drugs in the management of critically ill patients and beta-lactams are the most common antibiotic class used. Critically ill patient's pathophysiological factors lead to altered pharmacokinetics and pharmacodynamics of beta-lactams.A comprehensive bibliographic search in PubMed database of all English language articles published from January 2000 to December 2017 was performed, allowing the selection of articles addressing the pharmacokinetics or pharmacodynamics of beta-lactam antibiotics in critically ill patients.In critically ill patients, several factors may increase volume of distribution and enhance renal clearance, inducing high intra- and inter-patient variability in beta-lactam concentration and promoting the risk of antibiotic underdosing. The duration of infusion of beta-lactams has been shown to influence the fT > minimal inhibitory concentration and an improved beta-lactam pharmacodynamics profile may be obtained by longer exposure with more frequent dosing, extended infusions, or continuous infusions.The use of extracorporeal support techniques in the critically ill may further contribute to this problem and we recommend not reducing standard antibiotic dosage since no drug accumulation was found in the available literature and to maintain continuous or prolonged infusion, especially for the treatment of infections caused by multidrug-resistant bacteria.Prediction of outcome based on concentrations in plasma results in overestimation of antimicrobial activity at the site of infection, namely in cerebrospinal fluid and the lung. Therefore, although no studies have assessed clinical outcome, we recommend using higher than standard dosing, preferably with continuous or prolonged infusions, especially when treating less susceptible bacterial strains at these sites, as the pharmacodynamics profile may improve with no apparent increase in toxicity.A therapeutic drug monitoring-guided approach could be particularly useful in critically ill patients in whom achieving target concentrations is more difficult, such as obese patients, immunocompromised patients, those infected by highly resistant bacterial strains, patients with augmented renal clearance, and those undergoing extracorporeal support techniques.

The Surgical Infection Society Revised Guidelines on the Management of Intra-Abdominal Infection

BACKGROUND

Previous evidence-based guidelines on the management of intra-abdominal infection (IAI) were published by the Surgical Infection Society (SIS) in 1992, 2002, and 2010. At the time the most recent guideline was released, the plan was to update the guideline every five years to ensure the timeliness and appropriateness of the recommendations.

METHODS

Based on the previous guidelines, the task force outlined a number of topics related to the treatment of patients with IAI and then developed key questions on these various topics. All questions were approached using general and specific literature searches, focusing on articles and other information published since 2008. These publications and additional materials published before 2008 were reviewed by the task force as a whole or by individual subgroups as to relevance to individual questions. Recommendations were developed by a process of iterative consensus, with all task force members voting to accept or reject each recommendation. Grading was based on the GRADE (Grades of Recommendation Assessment, Development, and Evaluation) system; the quality of the evidence was graded as high, moderate, or weak, and the strength of the recommendation was graded as strong or weak. Review of the document was performed by members of the SIS who were not on the task force. After responses were made to all critiques, the document was approved as an official guideline of the SIS by the Executive Council.

RESULTS

This guideline summarizes the current recommendations developed by the task force on the treatment of patients who have IAI. Evidence-based recommendations have been made regarding risk assessment in individual patients; source control; the timing, selection, and duration of antimicrobial therapy; and suggested approaches to patients who fail initial therapy. Additional recommendations related to the treatment of pediatric patients with IAI have been included.

SUMMARY

The current recommendations of the SIS regarding the treatment of patients with IAI are provided in this guideline.

Pharmacokinetics of Imipenem/Cilastatin Burn Intensive Care Unit Patients Undergoing High-Dose Continuous Venovenous Hemofiltration

STUDY OBJECTIVE

High-dose continuous venovenous hemofiltration (CVVH) is a continuous renal replacement therapy (CRRT) used frequently in patients with burns. However, antibiotic dosing is based on inference from studies assessing substantially different methods of CRRT. To address this knowledge gap for imipenem/cilastatin (I/C), we evaluated the systemic and extracorporeal clearances (CLs) of I/C in patients with burns undergoing high-dose CVVH.

DESIGN

Prospective clinical pharmacokinetic study.

PATIENTS

Ten adult patients with burns receiving I/C for a documented infection and requiring high-dose CVVH were studied.

METHODS

Blood and effluent samples for analysis of I/C concentrations were collected for up to 6 hours after the I/C infusion for calculation of I/C total CL (CL_Total ), CL by CVVH (CL_HF ), half-life during CVVH, volume of distribution at steady state (Vd_ss ), and the percentage of drug eliminated by CVVH.

RESULTS

In this patient sample, the mean age was 50 ± 17 years, total body surface area burns was 23 ± 27%, and 80% were male. Nine patients were treated with high-dose CVVH for acute kidney injury and one patient for sepsis. The mean delivered CVVH dose was 52 ± 14 ml/kg/hour (range 32-74 ml/kg/hr). The imipenem CL_HF was 3.27 ± 0.48 L/hour, which accounted for 23 ± 4% of the CL_Total (14.74 ± 4.75 L/hr). Cilastatin CL_HF was 1.98 ± 0.56 L/hour, which accounted for 45 ± 19% of the CL_Total (5.16 + 2.44 L/hr). The imipenem and cilastatin half-lives were 1.77 ± 0.38 hours and 4.21 ± 2.31 hours, respectively. Imipenem and cilastatin Vd_ss were 35.1 ± 10.3 and 32.8 ± 13.8 L, respectively.

CONCLUSION

Efficient removal of I/C by high-dose CVVH, a high overall clearance, and a high volume of distribution in burn intensive care unit patients undergoing this CRRT method warrant aggressive dosing to treat serious infections effectively depending on the infection site and/or pathogen.

Pharmacokinetics and pharmacodynamics of antibiotics in critically ill acute kidney injury patients

Sepsis is the most common cause of death in critically ill patients and is associated with multiorgan failure, including acute kidney injury (AKI). This situation can require acute renal support and increase mortality. Therefore, it is essential to administer antimicrobials in doses that achieve adequate serum levels, avoiding both overdosing and drug toxicity as well as underdosing and the risk of antibiotic resistance and higher mortality. Currently, there are no validated guidelines on antibiotic dose adjustments in septic patients with AKI. The current recommendations were extrapolated from studies conducted in noncritical patients with end‐stage chronic kidney disease receiving chronic renal replacement therapy. This study aimed to review and discuss the complexity of this issue, considering several factors related to drug metabolism, the characteristics of critically ill patients, the properties of antimicrobial drugs and dialysis methods.

Pharmacokinetics of cefoperazone/sulbactam in critically ill patients receiving continuous venovenous hemofiltration

PURPOSE

Cefoperazone/sulbactam (CFP/SUL) is a β-lactam/β-lactamase inhibitor combination with little data available for the development of effective dosing guidelines during continuous renal replacement therapy. This study aimed to investigate the pharmacokinetics (PK) of cefoperazone/sulbactam in critically ill patients on continuous venovenous hemofiltration (CVVH).

METHODS

A prospective, single-center, and open-label study was conducted. Critically ill patients receiving CVVH with 3 g cefoperazone/sulbactam (2.0/1.0 g) intravenously every 8 h were recruited. Serial blood and ultrafiltrate samples were paired collected for initial dose (occasion 1) and steady state (occasion 2). PK was assessed by non-compartmental analysis, and pharmacodynamics (PD) was evaluated by the percent of time for which drug concentrations exceed the minimum inhibitory concentration (%T >MIC).

RESULTS

Total fourteen patients were enrolled. Volume of distribution at steady state (V ss) of cefoperazone and sulbactam for initial doses (20.8 ± and 28.4 L, respectively) increased significantly compared with those in healthy volunteers (P = 0.009 for CFP, P = 0.030 for SUL). Both cefoperazone and sulbactam showed significantly lower total clearance (CLt) (46.2 and 117.6 mL/min, respectively) compared with healthy volunteers (P = 0.000 for CFP, P = 0.017 for SUL). There is no significant difference in PK between occasion 1 and occasion 2 (P > 0.05). For occasion 1, mean CVVH clearance accounted for 34.3 and 33.9 % for CLt of cefoperazone and sulbactam, respectively. The minimum PD target of 60%T >MIC was achieved in seven of eight patients. For occasion 2, eight of nine patients achieved cefoperazone concentrations that were above the MIC for the entire dosing interval.

CONCLUSIONS

PK of cefoperazone/sulbactam was altered in critically ill patients undergoing CVVH. Therapeutic drug monitoring would be recommended to individualize the dose regimen.

Management of Acute Kidney Injury and Acid-Base Balance in the Septic Patient

Acute kidney injury (AKI) is an abrupt decrease in kidney function that takes place over hours to days. Sepsis is the leading cause of AKI and portends a particularly high morbidity and mortality, although the severity may vary from a transient rise in serum creatinine to end-stage renal disease. With regard to acid-base management in septic AKI, caution should be used with hyperchloremic crystalloid solutions, and dialysis is often used in the setting of severe acidosis. In the future, biomarkers may help clinicians identify AKI earlier and allow for potential interventions before the development of severe AKI.

Hospitalization for Pneumonia is Associated With Decreased 1-Year Survival in Patients With Type 2 Diabetes: Results From a Prospective Cohort Study

Diabetes mellitus is a frequent comorbid conditions among patients with pneumonia living in the community.The aim of our study is to evaluate the impact of hospitalization for pneumonia on early (30 day) and late mortality (1 year) in patients with type 2 diabetes mellitus.Prospective comparative cohort study of 203 patients with type 2 diabetes hospitalized for pneumonia versus 206 patients with diabetes hospitalized for other noninfectious causes from January 2012 to December 2013 at Policlinico Umberto I (Rome). Enrolled patients were followed up to discharge and up to 1 year after initial hospital admission or death.Overall, 203 patients with type 2 diabetes admitted to hospital for pneumonia were compared to 206 patients with type 2 diabetes admitted for other causes (39.3% decompensated diabetes, 21.4% cerebrovascular diseases, 9.2% renal failure, 8.3% acute myocardial infarction, and 21.8% other causes). Compared to control patients, those admitted for pneumonia showed a higher 30-day (10.8% vs 1%, P < 0.001) and 1-year mortality rate (30.3% vs 16.8%, P < 0.001). Compared to survivors, nonsurvivor patients with pneumonia had a higher incidence of moderate to severe chronic kidney disease, hemodialysis, and malnutrition were more likely to present with a mental status deterioration, and had a higher number of cardiovascular events during the follow-up period. Cox regression analysis found age, Charlson comorbidity index, pH < 7.35 at admission, hemodialysis, and hospitalization for pneumonia as variables independently associated with mortality.Hospitalization for pneumonia is associated with decreased 1-year survival in patients with type 2 diabetes, and appears to be a major determinant of long-term outcome in these patients.

Antimicrobial Pharmacokinetics and Pharmacodynamics

BACKGROUND

Antimicrobial medications are beneficial when used appropriately, but adverse effects and resistance sometimes limit therapy. These effects may be more problematic with inappropriate antimicrobial use. Consideration of the pharmacokinetic and pharmacodynamic properties of these medications can help optimize drug use.

METHODS

Review of the pertinent English-language literature.

RESULTS

The pharmacokinetic principles of absorption, distribution, metabolism, and elimination determine whether an appropriate dose of medication reaches the intended pathogen. The pharmacodynamic properties of antimicrobial medications define the relation between the drug concentration and its observed effect on the target pathogen. Improvements in clinical outcomes have been observed when antimicrobial agents are dosed optimally according to these properties. In surgical patients, substantial changes in the volume of distribution and elimination necessitate a clear understanding of these principles. Additionally, less adverse drug effects and antimicrobial resistance may occur with optimal use of these drugs.

CONCLUSION

Selecting and dosing antimicrobial medications with consideration of pharmacokinetics and pharmacodynamics may improve patient outcomes and avoid adverse effects.

Improving antimicrobial dosing in critically ill patients receiving continuous venovenous hemofiltration and the effect of pharmacist dosing adjustment

BACKGROUND

Appropriate antimicrobial dosing for patients receiving continuous venovenous hemofiltration (CVVH) is complex. Pharmacist participation in antimicrobial dosing adjustment for patients receiving CVVH may be advantageous.

METHODS

A comparative study was performed in a China hospital intensive care unit (ICU).Patients receiving CVVH in the intervention group received antimicrobial dosing adjustment service by pharmacists from January 2012 to June 2012, whereas patients in the control group received routine medical care between July 2012 and December 2012. The primary outcomes including patients' length of ICU stay, mortality in ICU, ICU hospitalization costs, and the occurrence of adverse drug events (ADEs) were then compared.

RESULTS

87 and 93 patients were included in the control and intervention groups. During the intervention period, pharmacists made 256 antimicrobial dosing adjustment recommendations for 93 enrolled patients receiving CVVH, of which 224 (87.5%) recommendations were accepted by physicians. Changing in CVVH-related variables (175, 68.4%) were the most common risk factors for dosing errors, whereas β-lactams (131, 51.2%) were the most frequency of antimicrobials associated with dosing errors. Compared with the control group, pharmacist dosing adjustment resulted in £1637.7 cost savings per patient, and 2.36 times reduction of antimicrobial-related adverse drug events (ADEs) (11 vs 26, P=0.002), while length of ICU stay and mortality in ICU showed no significant difference (P>0.05).

CONCLUSIONS

The involvement of pharmacist to participate in the ICU team rounds for patients receiving CVVH is associated with cost savings and reduction of ADEs. Hospital may consider employing ICU pharmacists.

The doripenem serum concentrations in intensive care patients suffering from acute kidney injury, sepsis, and multi organ dysfunction syndrome undergoing continuous renal replacement therapy slow low-efficiency dialysis

Doripenem is a novel wide-spectrum antibiotic, and a derivate of carbapenems. It is an ideal antibiotic for treatment of serious nosocomial infections and severe sepsis for its exceptionally high efficiency and broad antibacterial spectrum of action. Doripenem is eliminated mainly by the kidneys. In cases of acute kidney injury, dosing of doripenem depends on creatinine clearance and requires adjustments. Doripenem is eliminated during hemodialysis because its molecular weight is 300–400 Da. The aim of this study was to establish the impact of continuous renal replacement therapy (CRRT) slow low-efficiency dialysis (SLED) on doripenem serum concentrations in a population of intensive-therapy patients with life-threatening infections and severe sepsis. Ten patients were enrolled in this observational study. Twelve blood samples were collected during the first administration of doripenem in a 1-hour continuous infusion while CRRT SLED was provided. Fluid chromatography was used for measurement of the concentration of doripenem in serum. In all collected samples, concentration of doripenem was above the minimum inhibition concentration of this antibiotic. Based on these results, we can draw the conclusion that doripenem concentration is above the minimum inhibition concentration throughout all of CRRT. The dosing pattern proposed by the manufacturer can be used in patients receiving CRRT SLED without necessary modifications.

Optimizing antimicrobial therapy in critically ill patients

Critically ill patients with infection in the intensive care unit (ICU) would certainly benefit from timely bacterial identification and effective antimicrobial treatment. Diagnostic techniques have clearly improved in the last years and allow earlier identification of bacterial strains in some cases, but these techniques are still quite expensive and not readily available in all institutions. Moreover, the ever increasing rates of resistance to antimicrobials, especially in Gram-negative pathogens, are threatening the outcome for such patients because of the lack of effective medical treatment; ICU physicians are therefore resorting to combination therapies to overcome resistance, with the direct consequence of promoting further resistance. A more appropriate use of available antimicrobials in the ICU should be pursued, and adjustments in doses and dosing through pharmacokinetics and pharmacodynamics have recently shown promising results in improving outcomes and reducing antimicrobial resistance. The aim of multidisciplinary antimicrobial stewardship programs is to improve antimicrobial prescription, and in this review we analyze the available experiences of such programs carried out in ICUs, with emphasis on results, challenges, and pitfalls. Any effective intervention aimed at improving antibiotic usage in ICUs must be brought about at the present time; otherwise, we will face the challenge of intractable infections in critically ill patients in the near future.

Evolving practices in critical care and their influence on acute kidney injury

PURPOSE OF REVIEW

This review highlights the principal advances in critical care over the past year, and discusses the impact of these advances on the diagnosis and management of acute kidney injury (AKI).

RECENT FINDINGS

Recent literature has focused on assessment of volume status and fluid management, particularly in the setting of respiratory and cardiac failure. Other critical care topics are reviewed using a system-based approach.

SUMMARY

The incidence of AKI appears to be increasing, and despite advances in the provision of critical care and renal replacement therapies, there has been little improvement in its associated morbidity and mortality. Nonetheless, recent advances in critical care will impact the diagnosis and management of AKI, as well as shape the future research agenda. Continued work in the fields of critical care and nephrology will undoubtedly be centered on improved biomarkers for the detection of AKI, specific therapies to mitigate or reverse AKI, and techniques to prevent the development of AKI in the critically ill population.