João Pedro Baptista

Augmented renal clearance in the ICU: results of a multicenter observational study of renal function in critically ill patients with normal plasma creatinine concentrations*.

Objective:To describe the prevalence and natural history of augmented renal clearance in a cohort of recently admitted critically ill patients with normal plasma creatinine concentrations. Design:Multicenter, prospective, observational study. Setting:Four, tertiary-level, university-affiliated, ICUs in Australia, Singapore, Hong Kong, and Portugal. Patients:Study participants had to have an expected ICU length of stay more than 24 hours, no evidence of absolute renal impairment (admission plasma creatinine < 120 µmol/L), and no history of prior renal replacement therapy or chronic kidney disease. Convenience sampling was used at each participating site. Interventions:Eight-hour urinary creatinine clearances were collected daily, as the primary method of measuring renal function. Augmented renal clearance was defined by a creatinine clearance more than or equal to 130 mL/min/1.73 m2. Additional demographic, physiological, therapeutic, and outcome data were recorded prospectively. Measurements and Main Results:Nine hundred thirty-two patients were admitted to the participating ICUs over the study period, and 281 of which were recruited into the study, contributing 1,660 individual creatinine clearance measures. The mean age (95% CI) was 54.4 years (52.5–56.4 yr), Acute Physiology and Chronic Health Evaluation II score was 16 (15.2–16.7), and ICU mortality was 8.5%. Overall, 65.1% manifested augmented renal clearance on at least one occasion during the first seven study days; the majority (74%) of whom did so on more than or equal to 50% of their creatinine clearance measures. Using a mixed-effects model, the presence of augmented renal clearance on study day 1 strongly predicted (p = 0.019) sustained elevation of creatinine clearance in these patients over the first week in ICU. Conclusions:Augmented renal clearance appears to be a common finding in this patient group, with sustained elevation of creatinine clearance throughout the first week in ICU. Future studies should focus on the implications for accurate dosing of renally eliminated pharmaceuticals in patients with augmented renal clearance, in addition to the potential impact on individual clinical outcomes.

A comparison of estimates of glomerular filtration in critically ill patients with augmented renal clearance

IntroductionIncreasingly, derived estimates of glomerular filtration, such as the modification of diet in renal disease (MDRD) equation and Cockcroft-Gault (CG) formula are being employed in the intensive care unit (ICU). To date, these estimates have not been rigorously validated in those with augmented clearances, resulting in potentially inaccurate drug prescription.MethodsPost-hoc analysis of prospectively collected data in two tertiary level ICUs in Australia and Portugal. Patients with normal serum creatinine concentrations manifesting augmented renal clearance (ARC) (measured creatinine clearance (CLCR) > 130 ml/min/1.73 m2) were identified by chart review. Comparison between measured values and MDRD and CG estimates were then undertaken. Spearman correlation coefficients (rs) were calculated to determine goodness of fit, and precision and bias were assessed using Bland-Altman plots.ResultsEighty-six patients were included in analysis. The median [IQR] measured CLCR was 162 [145-190] ml/min/1.73 m2, as compared to 135 [116-171], 93 [83-110], 124[102-154], and 108 [87-135] ml/min/1.73 m2 estimated by CG, modified CG, 4-variable MDRD and 6-variable MDRD formulae. All of the equations significantly under-estimated the measured value, with CG displaying the smallest bias (39 ml/min/1.73 m2). Although a moderate correlation was noted between CLCR and CG (rs = 0.26, P = 0.017) and 4-variable MDRD (rs = 0.22, P = 0.047), neither had acceptable precision for clinical application in this setting. CG estimates had the highest sensitivity for correctly identifying patients with ARC (62%).ConclusionsDerived estimates of GFR are inaccurate in the setting of ARC, and should be interpreted with caution by the physician. A measured CLCR should be performed to accurately guide drug dosing.

Augmented renal clearance in septic patients and implications for vancomycin optimisation

The aim of this study was to evaluate the effect of augmented renal clearance (ARC) on vancomycin serum concentrations in critically ill patients. This prospective, single-centre, observational, cohort study included 93 consecutive, critically ill septic patients who started treatment that included vancomycin by continuous infusion, admitted over a 2-year period (March 2006 to February 2008). ARC was defined as 24-h creatinine clearance (CL(Cr))>130 mL/min/1.73 m(2). Two groups were analysed: Group A, 56 patients with a CL(Cr)≤130 mL/min/1.73 m(2); and Group B, 37 patients with a CL(Cr)>130 mL/min/1.73 m(2). Vancomycin therapeutic levels were assessed on the first 3 days of treatment (D(1), D(2) and D(3)). Serum vancomycin levels on D(1), D(2) and D(3), respectively, were 13.1, 16.6 and 18.6 μmol/L for Group A and 9.7, 11.7 and 13.8 μmol/L for Group B (P<0.05 per day). The correlation between CL(Cr) and serum vancomycin on D(1) was -0.57 (P<0.001). ARC was strongly associated with subtherapeutic vancomycin serum concentrations on the first 3 days of treatment.

Impact of antibiotic therapy in severe community-acquired pneumonia: Data from the Infauci study

&NA; Antibiotic therapy (AT) is the cornerstone of the management of severe community‐acquired pneumonia (CAP). However, the best treatment strategy is far from being established. To evaluate the impact of different aspects of AT on the outcome of critically ill patients with CAP, we performed a post hoc analysis of all CAP patients enrolled in a prospective, observational, multicentre study. Of the 502 patients included, 76% received combination therapy, mainly a &bgr;‐lactam with a macrolide (80%). AT was inappropriate in 16% of all microbiologically documented CAP (n = 177). Hospital and 6 months mortality were 34% and 35%. In adjusted multivariate logistic regression analysis, combination AT with a macrolide was independently associated with a reduction in hospital (OR 0.17, 95%CI 0.06–0.51) and 6 months (OR 0.21, 95%CI 0.07–0.57) mortality. Prolonged AT (>7 days) was associated with a longer ICU (14 vs. 7 days; p < 0.001) and hospital length of stay (LOS) (25 vs. 17 days; p < 0.001). Combination AT with a macrolide may be the most suitable AT strategy to improve both short and long term outcome of severe CAP patients. AT >7 days had no survival benefit and was associated with a longer LOS. Highlights:In SCAP, combination of antibiotics that includes a macrolide is associated a better hospital and 6 months survival.Courses of therapy longer than 7 days are not associated with survival benefit but lead to longer ICU and hospital LOS.Serum lactate showed to be a good prognostic marker of hospital mortality in SCAP patients.

Pneumonia eosinofílica aguda com evolução para síndroma de dificuldade respiratória aguda: caso clínico

The Authors present a case of acute eosinophilic pneumonia (AEP) associated with severe acute respiratory distress syndrome in a previously healthy young adult, medicated with nitrofurantoin. AEP must be included in the differential diagnosis of community adquired pneumonia, as well as a cause of acute respiratory distress syndrome; its diagnosis is suggested by the presence of eosinophilic alveolitis in bronchoalveolar lavage fluid. The early diagnosis of AEP and corticosteroid therapy may be lifesaving.

[Traumatic diaphragmatic hernias: retrospective analysis].

AIMS This study classifies cases of traumatic diaphragmatic hernias (TDH) in patients admitted to the Intensive Care Unit (ICU) of the Coimbra University Hospitals (HUC) from 1990 to 2004. METHODS Retrospective analysis of 34 cases of TDH, studying anatomical location, place and time of diagnosis, complementary tests aiding diagnosis, herniated organs, associated traumatism, morbidity and mortality. RESULTS Twenty-eight male and six female patients with an average age of 40.5 years +/- 20.5, average SAPS score 38.8. Average length of stay was 19.1 +/- 13.6 days, all suffered from closed traumatism and were put on artificial ventilation. The left-side diaphragm was more frequently affected (94.1%) then the right. Diagnosis in 19 cases was made up in the first six hours following the diagnosis of traumatism, in four cases within 12 hours and in the remaining cases between 48 hours and 16 years after traumatism. In 13 patients the diagnosis was established intra-operatively. The stomach was typically one of the herniated organs. The most frequently associated lesions at the thoracic level were pulmonary contusion, haemothorax and pneumothorax, and at the abdominal level, haemoperitoneum and splenic lesion. The rates for complications and mortality were 55.8% and 11.7% respectively. CONCLUSIONS TDH mainly occurs on the left side through closed thoraco-abdominal trauma following road traffic accidents. This group of patients, on average younger than others admitted to ICU, presents a longer average hospitalisation period, but has lower rates of mortality and lower SAPS severity scores. The most commonly herniated organ was the stomach and the most frequently encountered lesions were cranial-encephalic, splenic and pleural traumatisms. Pre-operative diagnosis of diaphragmatic injuries is difficult and a high index of clinical suspicion is needed after thoraco-abdominal trauma. This diagnosis should always be considered a possibility in cases of closed thoraco-abdominal traumas.

Fibrose Quística no adulto

RESUMO A Fibrose Quistica no momento actual nao constitui uma doenca exclusiva da idade pediatrica; o n.° de doentes adultos aumenta anualmente, preveudo-se que em 1996 metade dos doentes atingirao a idade adulta. A proposito da abert ura de uma Consulta para Adultos com Fibrose Quistica, avalia-se a sua actividade ao fim do 1.° ano, e tecem-se algumas eonsideracoes sobre o diagnostico de Fibrose Quistica na idade adulta.

Pneumonia nosocomial: Actualização terapêutica

Resumo A pneumonia nosocomial e uma doenca frequente, potencialmente fatal, e que apresenta elevada mortalidade. Neste artigo, apos revisao critica dos consensos e protocolos actuais para o tratamento da pneumonia nosocomial, sao actualizadas as bases racionais da antibioterapia, revendo os aspectos epidemiologicos, microbiologicos e farmacologicos. No final faz-se referencia ao posicionamento dos mais recentes antibioticos disponiveis para o seu tratamento.