Prevalence of acute kidney injury in intensive care units: the "COrte de prevalencia de disFunción RenAl y DEpuración en críticos" point-prevalence multicenter study.

PURPOSE: This study aimed to measure the point prevalence of kidney dysfunction (KD) in the intensive care setting. MATERIALS AND METHODS: A point-prevalence, single-day, prospective study was conducted. Of 919 patients present in 42 Intensive care units (ICUs) for 2 specific days (September 2009 and March 2010), 832 cases were included. Mild KD was defined as a measured creatinine clearance of 90 to 60 mL min(-1) 1.73 m(-2), and severe KD was defined as a creatinine clearance less than 60 mL min(-1) 1.73 m(-2). RESULTS: Prevalence of mild KD was 15.9/100 patients/d (13.5-18.5), and severe KD was 42.4/100 patients/d (39.1-45.8). We considered as having a low probability of experiencing KD those patients without chronic kidney disease, acute kidney injury network stage 0, and a serum creatinine less than 1.2 mg/dL, but among them (557 patients), 18.1% (15.2%-21.6%) had mild KD and 24.2% (20.9%-28%) had severe KD. ICU mortality was 10.6% (7.81%-14.4%) for patients without dysfunction, 16.6% (11.2%-24%) for patients with mild KD, and 29.7% (25.2%-34.7%; P<.001) for patients with severe KD, with a relative risk for severe KD vs no KD of 2.54 (1.90-3.40). In 54.3% patients, at least 1 renal insult was reported. One nephrotoxic drug was administered to 34.4% and 2 or more to 14.9% patients, with a lower frequency among those with chronic kidney disease (30.6% vs 50.8%; P<.05). CONCLUSIONS: Each day of study, more that half of the patients admitted to the ICU showed some derangement in kidney function. More than 25% of patients not fulfilling the KD criteria by serum creatinine or acute kidney injury network showed, in fact, a severe KD, and this finding was associated with higher mortality. More than 50% of the patients admitted to the ICU were subjected to at least 1 renal insult.

Estimating kidney function in the critically ill patients.

Glomerular filtration rate (GFR) is an accepted measure for assessment of kidney function. For the critically ill patient, creatinine clearance is the method of reference for the estimation of the GFR, although this is often not measured but estimated by equations (i.e., Cockroft-Gault or MDRD) not well suited for the critically ill patient. Functional evaluation of the kidney rests in serum creatinine (Crs) that is subjected to multiple external factors, especially relevant overhydration and loss of muscle mass. The laboratory method used introduces variations in Crs, an important fact considering that small increases in Crs have serious repercussion on the prognosis of patients. Efforts directed to stratify the risk of acute kidney injury (AKI) have crystallized in the RIFLE or AKIN systems, based in sequential changes in Crs or urine flow. These systems have provided a common definition of AKI and, due to their sensitivity, have meant a considerable advantage for the clinical practice but, on the other side, have introduced an uncertainty in clinical research because of potentially overestimating AKI incidence. Another significant drawback is the unavoidable period of time needed before a patient is classified, and this is perhaps the problem to be overcome in the near future.

A comparison of the effect of convection against diffusion in hemodynamics and cytokines clearance in an experimental model of septic shock.

BACKGROUND: Replacement therapies based on the use of convection have value for the removal of inflammatory mediators. Such therapies have been proposed for the management of septic shock, but diffusion has not proved useful in this scenario, unless high-flow membranes are used. The exact role of diffusion in these cases remains to be clarified because continuous replacement therapies are usually delivered with low-flow membranes and mixed convection-diffusion modalities. However, studies specifically addressing this problem have not been performed. Our aim was to define the efficacy of hemofiltration (convection) and hemodialysis (diffusion) in cytokine clearance and hemodynamic improvement in an experimental model of septic shock. METHODS: Shock was induced in 15 beagle dogs (weight 10-15 kg) by infusion of 1 mg/kg of ultrapure Escherichia coli lipopolysaccharide diluted in 20 mL saline for 10 minutes. Five animals were followed without interventions (controls), five animals were treated with convection (100 mL kg h) for 6 hours, and five animals were treated with diffusion (100 mL kg h) for 6 hours. RESULTS: All subjects in the control group died during the study, whereas all treated subjects survived. Mean arterial pressure, cardiac output, systolic variability volume, systemic vascular resistances, dPMax, and pulmonary compliance improved in treated subjects. However, the differences in mean arterial pressure and cardiac output were significant only in the convection group and not in the diffusion-treated group.Tumor necrosis factor α rose equally in all groups and decreased only in treated subjects. Interleukin 6 rose in the three groups but decreased only in the convection group and remained unchanged in the control and diffusion groups. CONCLUSION: Convection and diffusion improved survival and hemodynamic parameters in a septic shock model. Improvement was more pronounced with convection, a difference that may be explained by convective clearance of cytokines.

Bladder mucosal CO2 compared with gastric mucosal CO2 as a marker for low perfusion states in septic shock.

Recent reports indicate the possible role of bladder CO(2) as a marker of low perfusion states. To test this hypothesis, shock was induced in six beagle dogs with 1 mg/kg of E. coli lipopolysaccharide, gastric CO(2) (CO(2)-G) was measured with a continuous monitor, and a pulmonary catheter was inserted in the bladder to measure CO(2) (CO(2)-B). Levels of CO(2)-B were found to be lower than those of CO(2)-G, with a mean difference of 36.8 mmHg (P < 0.001), and correlation between both measurements was poor (r(2) = 0.16). Even when the correlation between CO(2)-G and ΔCO(2)-G was narrow (r(2) = 0.86), this was not the case for the relationship between CO(2)-B and ΔCO(2)-B (r(2) = 0.29). Finally, the correlation between CO(2)-G and base deficit was good (r(2) = 0.45), which was not the case with the CO(2)-B correlation (r(2) = 0.03). In our experience, bladder CO(2) does not correlate to hemodynamic parameters and does not substitute gastric CO(2) for detection of low perfusion states.

Discrepancies in the RIFLE classification are due to the method used to assess the level of derangement of kidney function.

PURPOSE: We hypothesized that RIFLE based on creatinine clearance (CrCl) is superior to that based on serum creatinine (sCr) or Cockroft-Gault (C-G) because it is an earlier marker of kidney dysfunction. MATERIALS AND METHODS: At day 3 of admission, we compared the RIFLE based on sCr, C-G, and CrCl with 28-day mortality and development of RIFLE-F during intensive care unit stay. RESULTS: Percentages in the RIFLE levels were similar for the 3 estimates, but the patients included in each level were different; with CrCl as the reference, κ statistic was 0.29 (95% confidence interval, 0.15-0.43) for sCr and 0.21 (0.07-0.36) for C-G. Mortality at day 28 was 19.3%, with percentages of mortality increasing with RIFLE based in CrCl but not sCr or C-G (area under the curve, 0.57 [45-72] for C-G; 0.57 [44-72] for sCr; and 0.64 [52-79] for CrCl). Logistic regression only showed an independent relationship with mortality for RIFLE measured with CrCl. CONCLUSIONS: RIFLE classification using sCr or C-G at the third day of admission predicts outcome less accurately than with the use of CrCl. Because of the delay in the rise of sCr after a sudden glomerular filtration rate decrease, RIFLE based in CrCl may represent an advantage in terms of precocity.

Seafood intoxication by tetrodotoxin: first case in Europe.

BACKGROUND: Tetrodotoxin is considered the most lethal toxin in the marine environment. Prior cases of intoxication previously described correspond to consumption of tetrodotoxin in tropical or subtropical regions of Asia or the Pacific Islands. OBJECTIVES: We present the first European case of tetrodotoxin intoxication in a patient who ingested part of a trumpet shellfish (Charonia sauliae) from the Atlantic Ocean in Southern Europe. CASE REPORT: Our patient suffered general paralysis, including the respiratory muscles, a few minutes after the consumption of a few grams of C. sauliae. Intubation and mechanical ventilation were necessary for 52 h after the intoxication. The corresponding electrophysiologic studies showed complete non-excitability, with no recordable sensory or motor nerve conduction. We detected the presence of tetrodotoxin in the mollusk and the patient's blood and urine by means of high-performance liquid chromatography-mass spectrometry analysis technique. A previous bioassay showed extremely high quantities of the toxin in the mollusk. CONCLUSIONS: This case alerts us to the possibility of a very harmful biotoxin in European coastal waters. This now should be included in the differential diagnosis of similar cases in Europe, and we must be vigilant for its possible presence in Europe.

Replacement of 24-h creatinine clearance by 2-h creatinine clearance in intensive care unit patients: a single-center study.

OBJECTIVE: To estimate the usefulness of 2-h creatinine clearance (CrCl) in the ICU and define variables that may reduce agreement. DESIGN: Prospective study. SETTING: Polyvalent ICU of a university hospital. PATIENTS: 359 patients. INTERVENTIONS: We compared 24-h CrCl (CrCl-24h), as the standard measure, with 2-h CrCl (CrCl-2h) (at the start of the period) and the Cockroft-Gault equation (Ck-G). MEASUREMENTS AND RESULTS: The 2-h sample was lost in two patients (0.6%) and the 24-h sample was lost in 50 patients (13.9%). The mean Ck-G was 87.4+/-3.05, with CrCl-2h 109.2+/-4.46 and CrCl-24h 100.9+/-4.21 ml/min/1.73 m2 (r2 of 0.88 for CrCl-2h and 0.84 for Ck-G). The differences from ClCr-24h were 21.8+/-3.3 (p<0.001) for the Ck-G and 8.3+/-2.6 (p<0.05) for CrCl-2h (p<0.05). In the subgroup of patients with CrCl-24h<100 ml/min/1.73 m2, the CrCl-24h value was 52.9+/-2.71 vs. 51.6+/-2.14 for CrCl-2h (p=ns) and 57.6+/-2.56 (p<0.001) for the Ck-G. Patients with CrCl<100 ml/min only showed variability in hyperglycemia during the 24-h period. CONCLUSIONS: In intensive care patients, 24-h CrCl results in a large proportion of non-valid determinations, even under conditions of close monitoring. Two-hour CrCl is an adequate substitute, even in patients who are unstable or who have irregular diuresis where a 24-h collection is impossible. The Cockroft-Gault equation seems less useful in this setting.

Early hemodynamic improvement is a prognostic marker in patients treated with continuous CVVHDF for acute renal failure.

We examined whether hemodynamic improvement after high-flow hemofiltration predicts survival in patients treated with standard continuous renal replacement therapy (CRRT). This was a prospective, observational cohort study of 169 patients, measuring the mean arterial pressure (MAP) and norepinephrine (NE) dosage before and 24 hours after CRRT. Responders were defined as having a 20% reduction in NE dosage or a 20% rise in MAP with no increase in NE, compared with nonresponders. Patients were considered to be unstable if they were receiving NE or their MAP was lower than 60 mm Hg before CRRT. Of the 169 patients, 68% were men; mean age was 53.8 years (52.7 to 54.9), with a mean Acute Physiology and Chronic Health Evaluation (APACHE) II at admission of 21.8 (21.2 to 22.3), of whom 114 were unstable at the start of CRRT. Overall mortality rate 15 days after the end of CRRT was 54.3% (57.7% in stable vs. 52.9% in unstable patients, p = NS). There were 99 responders and 70 nonresponders, the only differences being NE dosage (higher in responders, p < 0.01) and mortality rate (responders 30% vs. nonresponders 74.7%, p < 0.001). In unstable patients, mortality rate was 30% in responders versus 87% in nonresponders (p < 0.001) (72% sensitivity and 86% specificity for predicting death). Logistic regression analysis showed that the only variables associated with death were APACHE II at admission (OR, 1.06; 95% CI, 1.0 to 1.12), percent creatinine decrease (OR, 0.98; CI, 0.96 to 1.0), and lack of hemodynamic response to CRRT (OR, 7.04; CI, 3.3 to 15.02). Hemodynamic improvement after 24-hour CRRT is a strong predictor of survival.

[Serum C-reactive protein as a marker of outcome and infection in critical care patients]. / Valor de la determinación de la proteína C reactiva como marcador pronóstico y de infección en pacientes críticos.

BACKGROUND AND OBJECTIVE: C-reactive protein (CRP) has been considered a marker for infection and an aid for diagnosing sepsis. We analyze the relation of CRP to infection and outcome in intensive care units (ICU) patients. PATIENTS AND METHOD: Prospective study on 77 ventilated patients. Expected short ICU stay or (suspected or confirmed) infection at admission were excluding criteria. 55 admissions after elective surgery were the controls. CRP measurement the first (CRP-1), third (CRP-3) and sixth (CRP-6) day of stay. APACHE II (Acute Physiology Score and Chronic Health Evaluation), SOFA (Sepsis-related Organ Failure Assessment), shock, respiratory or renal failure, leucocytes, platelets and albumin were registered. Follow-up until day 9 for infection and ICU discharge for outcome. RESULTS: CRP-1 in controls was 5.3 (3.9) mg/l and cases 67.8 (77.4) (p < 0.001). Shock on admission was related to CRP-1: patients in shock had higher CRP-1 levels (118.6 [82.8] vs 62.8 [75.6]; p = 0.06). 40.25% of cases developed infection, and CRP-1 levels were higher in this patients (88.8 [93.9] vs 53.8 [60.9]; p < 0.05). ROC area under curve was 0.6 with a sensibility of 23% and a specificity of 89% for a level of CRP-1 > 100. Mortality was 23.4% in cases and 1.8% in controls. Age, shock, APACHE II and SOFA were related to mortality, but CRP-1 did not. ROC area under curve for CRP-1 as mortality predictor in all patients was 0.62 (0.76 for APACHE II and 0.77 for SOFA) but only in cases was of 0.49 (0.69 for APACHE II and 0.67 for SOFA). CONCLUSIONS: CRP level on admission is an useful marker for early infection but not for outcome in critically ill patients admited to the ICU.

Valor de la determinación de la proteína C reactiva como marcador pronóstico y de infección en pacientes críticos / Serum C-reactive protein as a marker of outcome and infection in critical care patients

Fundamento y objetivo: Analizar la utilidad de la proteína C reactiva (PCR) como marcador pronóstico y de infección en pacientes ingresados en unidades de cuidados intensivos (UCI). Pacientes y método: Se ha realizado un estudio prospectivo en 77 pacientes ventilados mecánicamente sin infección (sospechada o confirmada) en el momento del ingreso; el grupo control estuvo formado por 55 ingresos tras cirugía electiva. Determinamos el valor de PCR los días 1 (PCR-1), 4 (PCR-4) y 7 (PCR-7). Se registraron el APACHE-II (Acute Physiology Score and Chronic Health Evaluation) y SOFA (Sepsis-related Orgam Failure Assessment) al ingreso y la presencia de shock, fallo respiratorio o renal, así como la cifra de leucocitos, plaquetas y albúmina sérica durante el seguimiento (10 días para el análisis de infecciones y hasta el alta de la UCI para el del pronóstico). Resultados: El valor medio (desviación estándar) de la PCR-1 en los controles fue de 5,3 (3,9) mg/l, frente a 67,8 (77,4) mg/l en los casos (p < 0,001). Los casos con shock en el momento del ingreso presentaron valores más elevados de PCR-1 (118,6 [82,8] frente a 62,8 [75,6] mg/l, p = 0,06). El 40,25% de los casos desarrolló infección y presentó valores de PCR-1 más elevados (88,8 [93,9] comparado con 53,8 [60,9] mg/l, p < 0,05). La sensibilidad fue del 23% y la especificidad del 89% para un valor de PCR-1 superior a 100 (area bajo la curva de 0,6). Las mortalidad en los casos fue del 23,4%. La PCR-1 no se relacionó con el pronóstico en este grupo: el área bajo la curva para PCR-1 mayor de 100 como predictor de mortalidad en toda la población fue de 0,62, pero en los casos fue sólo de 0,49 (0,69 para APACHE-II y 0,67 para SOFA). Conclusiones: El valor sérico de la PCR en el momento del ingreso es un marcador temprano de infección pero no es útil como marcador pronóstico en pacientes críticos sometidos a ventilación mecánica al ingresar en la UCI

Risk factors for renal dysfunction in the postoperative course of liver transplant.

Renal dysfunction (RD) is a frequent complication after orthotopic liver transplantation (OLT), and it has an unfavorable effect on the prognosis of OLT patients. The purpose of our study was to identify possible risk factors for RD and its impact on survival. The possible relations of pre-, peri-, and postoperative variables to early-onset renal dysfunction (ED) (within the 1st 3 months), late-onset renal dysfunction (LD) (between 3 and 6 months), and chronic renal dysfunction (CRD) (beyond 6 months) was analyzed. We studied 245 liver transplants in 241 patients. RD was found in 64.1% of these patients, and 69% of the patients with RD recovered. LD was found in 16.7% of the transplant patients. In the multivariate analysis, baseline serum creatinine, perioperative volume of transfused bank-red blood cells, Acute Physiology and Chronic Health Evaluation (APACHE) II score at intensive care unit (ICU) admission, and infection were associated with the development of RD. Overall mortality was 27.8% and for the RD group, it was 33.5%. LD, but not ED, was related to lower survival (together with graft dysfunction and APACHE II score at ICU admission). In conclusion, ED is frequent alter OLT and is related to preexisting RD, the volume of transfused bank--red blood cells during surgery, higher APACHE II score at ICU admission, and infection. In general, the prognosis for ED is good, in contrast with that of LD, which is associated with diminished survival.

[Postoperative complications of liver transplantation: relationship with mortality]. / Complicaciones postoperatorias en el trasplante hepático. Relación con la mortalidad.

BACKGROUND AND OBJECTIVE: Liver transplant is an effective procedure for fulminant hepatitis or chronic liver disease and offers an adequate quality of life. However, even though it is a consolidated treatment, patients can develop serious complications in the immediate postoperative course. PATIENTS AND METHOD: Prospective observational study of 131 patients admitted in our intensive care unit after liver transplant surgery. We studied variables related with the development of complications and their relation to outcome. RESULTS: Intensive care unit mortality was 11.5%. Median stay was 4 days. 90% of patients presented 2 or more complications. Hyperglycemia, thrombocytopenia and hypothermia were the most frequent complications but they were not related with mortality. Less frequent but related to outcome complications were acute renal failure (23.6% mortality vs. 1.3%; p < 0.01), ADRS (63.6% vs 6.7%; p < 0,01), low cardiac output (71.4% vs 4.3%; p < 0.01), > or = 2 vasoactive drugs (61.9% vs 1.8%; p < 0.01), encephalopathy (37.5% vs 9.8%; p < 0.05), pneumonia (80% vs 8%; p < 0.01) and hemorrhage (29.4% vs 8.8%; p < 0.05). Graph ischemia, coagulopathy, reperfusion syndrome and use of blood derivatives during surgery were factors related with the development of complications and mortality. Multivariate analysis showed a relationship with mortality and low cardiac output, number of vasoactive drugs and total time of graft ischemia. CONCLUSIONS: Complications during the postoperative course of liver transplant are frequent but most of them have no effect on prognosis. The negative effect of severe complications should be limited by optimizing the hemodynamic support in these patients and minimizing ischemia of transplanted organs.