Lung-protective mechanical ventilation does not protect against acute kidney injury in patients without lung injury at onset of mechanical ventilation

Introduction

Preclinical and clinical studies suggest that mechanical ventilation contributes to the development of acute kidney injury (AKI), particularly in the setting of lung-injurious ventilator strategies.

Objective

To determine whether ventilator settings in critically ill patients without acute lung injury (ALI) at onset of mechanical ventilation affect the development of AKI.

Design, Setting, and Patients

Secondary analysis of a randomized controlled trial (N = 150), comparing conventional tidal volume (V_T, 10 mL/kg) with low tidal volume (V_T, 6 mL/kg) mechanical ventilation in critically ill patients without ALI at randomization. During the first 5 days of mechanical ventilation, the RIFLE class was determined daily, whereas neutrophil gelatinase–associated lipocalin and cystatin C levels were measured in plasma collected on days 0, 2, and 4.

Results

Eighty-six patients had no AKI at inclusion, and 18 patients (21%) subsequently developed AKI, but without significant difference between ventilation strategies. (Cumulative hazard, 0.26 vs 0.23; P = .88.) The courses of neutrophil gelatinase–associated lipocalin and cystatin C plasma levels did not differ significantly between randomization groups.

Conclusion

In the present study in critically patients without ALI at onset of mechanical ventilation, lower tidal volume ventilation did not reduce the development or worsening of AKI compared with conventional tidal volume ventilation.     

Goal-directed therapy after cardiac surgery and the incidence of acute kidney injury

Objective

The purpose of this study was to assess the effect of goal-directed therapy (GDT), after cardiac surgery, on the incidence of acute kidney injury (AKI).

Design

This is a prospective observational study designed to achieve and maintain maximum stroke volume for 8 hours, in patients after cardiac surgery.

Setting

This is a single-center study in a 15-bedded cardiothoracic intensive care unit (ICU).

Participants

Participants are patients after coronary artery bypass grafting and/or aortic valve surgery.

Interventions

Patients in the GDT group received cardiac output monitoring and fluid challenges targeting an increase in stroke volume by at least 10%. Stroke volume maximization was maintained for a period of 8 hours from admission to the ICU. All other aspects of care were dictated by the clinical team. Patients in the standard therapy (ST) group had intravenous fluids in accordance with the routine practice of the unit. Patients were divided into the GDT and ST group dependant on availability of cardiac output monitors and allocation of nursing staff with training in GDT. Patients’ data were collected prospectively in both groups.

Measurements and main results

One hundred twenty-three patients received GDT compared with 141 patients in the ST group. Both groups received similar volumes of fluid (GDT, 2905 [1367] mL vs 2704 [1393] mL; P = .09). Incidence of AKI was reduced in the GDT group (n = 8 [6.5%] vs n = 28 [19.9%]; P = .002). The median duration of hospital stay was 6 (4) days in the GDT group vs 7 (8) days in the ST, P = .004.

Conclusion

Postoperative GDT in patients after cardiac surgery was associated with reduction in the incidence of AKI and a reduction in ICU and hospital duration of stay.     

Fractional excretion of urea as a diagnostic index in acute kidney injury in intensive care patients

Purpose

Acute kidney injury (AKI) is a dynamic process that evolves from an early reversible condition to an established disease. Value of urine indices in the event of AKI is uncertain in critically ill patients. The aim of this study was to evaluate the performance of fractional excretion of urea (FeU) for differentiating persistent from transient AKI in patients admitted to the intensive care unit.

Methods

This was an observational study. Forty-seven patients with AKI according to the RIFLE classification were included. Transient AKI was defined as AKI resolved within 3 days after inclusion. Persistent AKI was defined as persistent serum creatinine elevation or oliguria.

Results

Fractional excretion of urea was lower in case of transient, 33% (25-39), than persistent AKI, 47% (36-61) (P = .001). Areas under the receiver operating characteristic curve for FeU in case of transient AKI were better than those for other urinary indexes, 0.78 (95% confidence interval, 0.63-0.92). Optimal cutoff point according to the receiver operating characteristic curve was 40%. In patients treated with diuretics, FeU was the only predictive index of transient AKI. Fractional excretion of urea gradually increased from days 1 to 7 in transient AKI, whereas plasma creatinine decreased.

Conclusions

Fractional excretion of urea less than 40% was found to be a sensitive and specific index in differentiating transient from persistent AKI in intensive care unit patients especially if diuretics had been administered.     

Clinical outcome of kidney transplantation from deceased donors with acute kidney injury by Acute Kidney Injury Network criteria

Purpose

In this study, we investigated the outcome of kidney transplantation (KT) from deceased donors with acute kidney injury (AKI), as defined by the Acute Kidney Injury Network criteria.

Methods

Of 156 deceased donors, kidneys from 43 donors (27.6%) with AKI were transplanted into 57 recipients (AKI group). Another 147 recipients received kidneys from donors without AKI (non-AKI group). We compared the incidence of delayed graft function, allograft function for 1 year after KT, and long-term (5 and 10 years) graft survival rate between the 2 groups.

Results

Delayed graft function developed more frequently in the AKI group than in the non-AKI group (42.1% vs 12.2%; P < .05), and allograft function—assessed by the modification of diet in renal disease equation—showed a significantly deteriorating pattern at 2 weeks and 1, 3, and 6 months after KT compared with that in the non-AKI group (P < .05 for comparisons at each time point). However, allograft function at 12 months after KT and the long-term allograft and patient survival rates did not differ between the AKI and non-AKI groups.

Conclusions

In KT from deceased donors, the AKI group that received kidneys with AKI, as defined by the Acute Kidney Injury Network criteria, showed a higher delayed graft function rate and lower allograft function for 6 months after KT but no effect on allograft function 1 year after KT and on long-term allograft survival.     

Urine biochemistry in septic and non-septic acute kidney injury: a prospective observational study

Purpose

Determine whether there are unique patterns to the urine biochemistry profile in septic compared with non-septic acute kidney injury (AKI) and whether urinary biochemistry predicts worsening AKI, need for renal replacement therapy and mortality.

Materials and Methods

Prospective cohort study of critically ill patients with septic and non-septic AKI, defined by the RIFLE (Risk, Injury, Failure, Loss, End-Stage) criteria. Urine biochemistry parameters were compared between septic and non-septic AKI and were correlated with neutrophil gelatinase-associated lipocalin (NGAL), worsening AKI, renal replacement therapy (RRT), and mortality.

Results

Eighty-three patients were enrolled, 43 (51.8%) with sepsis. RIFLE class was not different between groups (P = .43). Urine sodium (UNa) < 20 mmol/L, fractional excretion of sodium (FeNa) < 1%, and fractional excretion of urea (FeU) < 35% were observed in 25.3%, 57.8%, and 33.7%, respectively. Septic AKI had lower UNa compared with non-septic AKI (P = .04). There were no differences in FeNa or FeU between groups. Urine NGAL was higher for FeNa≥1% compared to FeNa<1% (177.4 ng/mL [31.9-956.5] vs 48.0 ng/mL [21.1-232.4], P = .04). FeNa showed low correlation with urine NGAL (P = .05) and plasma NGAL (P = .14). There was poor correlation between FeU and urine NGAL (P = .70) or plasma NGAL (P = .41). UNa, FeNa, and FeU showed poor discrimination for worsening AKI, RRT and mortality.

Conclusion

Urine biochemical profiles do not discriminate septic and non-septic AKI. UNa, FeNa, and FeU do not reliably predict biomarker release, worsening AKI, RRT or mortality. These data imply limited utility for these measures in clinical practice in critically ill patients with AKI.     

Additional predictive value of serum potassium to Thrombolysis In Myocardial Infarction risk score for early malignant ventricular arrhythmias in patients with acute myocardial infarction

Objective

The aim of this study was to evaluate the additional predictive value of serum potassium (SK) to Thrombolysis In Myocardial Infarction (TIMI) risk score for malignant ventricular arrhythmias (MVA) in patients within 24 hours of acute myocardial infarction (AMI).

Methods

This was a 6-year retrospective study. The receiver operating characteristic curve was used to evaluate the predictive value of SK and TIMI risk score for MVA attack. In addition, SK-modified TIMI risk score was created by incorporating SK information into the usual score; the accuracy of new score was compared with that of the usual TIMI risk score by comparing the area under the receiver operating characteristic curves (AUC).

Results

Among the 468 patients enrolled, the incidence of MVA 24 hours after AMI was 9.4%, and it was higher in the hypokalemia group compared with that of the normokalemic group (27.3% vs 7.5%, P < .001; odds ratio, 4.594; 95% confidence interval [CI], 2.159-9.774). A significant predictive value of SK was indicated by AUC of 0.787 (95% CI, 0.747-0.823, P < .01). Serum potassium remained a predictor of MVA after being adjusted by the variables in TIMI risk score. The AUC of TIMI risk score in relation to MVA was 0.586 (95% CI, 0.54-0.631; P = .0676). The incorporation of SK into TIMI risk score improved its predictive value for MVA attack (AUC = 0.66; 95% CI, 0.568-0.753; P < .001), with significant difference between AUC of the new score and that of the original risk score (Z = 2.474, P = .013).

Conclusions

Serum potassium on admission to the emergency department may be used as a valuable predictor and could add predictive information to some extent to TIMI risk score for MVA attack during 24-hour post-AMI.     

African American race,obesity, and blood product transfusion are risk factors for acute kidney injury in critically ill trauma patients

Purpose

Acute kidney injury (AKI) is a common source of morbidity after trauma. We sought to determine novel risk factors for AKI, by Acute Kidney Injury Network (AKIN) criteria, in critically ill trauma patients.

Materials and Methods

A prospective cohort of 400 patients admitted to the intensive care unit of a level 1 trauma center was followed for the development of AKI over 5 days.

Results

Acute kidney injury developed in 147 (36.8%) of 400 patients. In multivariable regression analysis, independent risk factors for AKI included African American race (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.08-3.18; P = .024), body mass index of 30 kg/m² or greater (OR, 4.72 versus normal body mass index; 95% CI, 2.59-8.61; P < .001), diabetes mellitus (OR, 3.26; 95% CI, 1.30-8.20; P = .012), abdominal Abbreviated Injury Scale score of 4 or more (OR, 3.78; 95% CI, 1.79-7.96; P < .001), and unmatched packed red blood cells administered during resuscitation (OR, 1.13 per unit; 95% CI, 1.04-1.23; P = .004). Acute Kidney Injury Network stages 1, 2, and 3 were associated with hospital mortality rates of 9.8%, 13.7%, and 30.4%, respectively, compared with 3.8% for those without AKI (P < .001).

Conclusions

Acute kidney injury in critically ill trauma patients is associated with substantial mortality. The findings of African American race, obesity, and blood product administration as independent risk factors for AKI deserve further study to elucidate underlying mechanisms.     

Urine output is associated with prognosis in patients with acute kidney injury requiring continuous renal replacement therapy

Purpose

Although some studies have found that early initiation of continuous renal replacement therapy (CRRT) is associated with better prognosis, no consensus exists on the best timing to start CRRT. We investigated whether the timing of CRRT initiation was relevant to overall mortality and explored which factors at the time of CRRT initiation were associated with better outcomes in critically ill patients with acute kidney injury (AKI).

Materials and Methods

A total of 361 patients who received CRRT for AKI between 2009 and 2011 were collected and divided into 2 groups based on the median blood urea nitrogen (BUN) levels or 6-hour urine output immediately before CRRT was started. The impact of the timing of CRRT initiation stratified by BUN concentration or urine output on 28-day all-cause mortality was compared between groups.

Results

When the timing of CRRT initiation was stratified by 6-hour urine output, 28-day all-cause mortality rates were significantly lower in the nonoliguric group compared with the oliguric group (P = .02). In contrast, clinical outcomes were not different between the low-BUN and the high-BUN groups (P = .30). Cox regression analysis revealed that 28-day all-cause mortality risk was significantly lower in the nonoliguric group stratified by 6-hour urine output, even after adjusting for age, sex, mean arterial pressure, Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores, and serum biomarkers (hazard ratio, 0.85; 95% confidence interval, 0.65-0.99; P = .04).

Conclusions

Urine output but not BUN concentration was significantly associated with a better prognosis in critically ill patients with AKI requiring CRRT.     

Severe lactic acidosis in critically ill patients with acute kidney injury treated with renal replacement therapy

Purpose

Severe lactic acidosis (SLA) is frequent in intensive care unit (ICU) patients with acute kidney injury (AKI) treated with renal replacement therapy (RRT). The aim of the study is to describe the epidemiology of SLA in this setting.

Materials and methods

An observational single-center cohort analysis was performed on AKI patients treated with RRT. At initiation of RRT, SLA patients (serum lactate concentration > 5 mmol/L and pH < 7.35) were compared with non-SLA patients.

Results

Of the 454 patients dialyzed during the study period, 342 patients matched inclusion criteria (116 with and 226 patients without SLA). In SLA patients, lactate stabilized/decreased in 69.7% at 4 hours (P = .001) and in 81.8% during the period of 4 to 24 hours (P < .001) after initiation of RRT. Mortality during this 24-hour period was 31.0%. Intensive care unit mortality was 83.6% compared with 47.3% in non-SLA patients. Initial lactate concentration was not related to ICU mortality in SLA patients.

Conclusions

Severe lactic acidosis was frequent in AKI patients treated with RRT. Severe lactic acidosis patients were more severely ill and had higher mortality compared with patients without. During the first 24 hours of RRT, a correction of lactate concentration and acidosis was observed. In SLA patients, lactate concentration at initiation of RRT was not able to discriminate between survivors and nonsurvivors.     

Application of the Sequential Organ Failure Assessment score for predicting mortality in patients with acute myocardial infarction

Background

Thrombolysis in Myocardial Infarction (TIMI) score and Global Registry of Acute Coronary Events (GRACE) score have been validated as predictors of death in patients with acute myocardial infarction (AMI). This study was undertaken to determine whether the Sequential Organ Failure Assessment (SOFA) score had good accuracy for predicting mortality in AMI patients, and to compare the discriminatory performance of the 3 risk scores (RSs).

Methods

This was a retrospective study. We calculated the TIMI RS, GRACE RS, and SOFA score for 726 consecutive AMI patients. The study endpoint was all-cause mortality. All patients were followed up for at least 3 years or until the occurrence of death. The area under the receiver operating characteristic curve (AUC) was used to evaluate the predictive ability of each score at different time points.

Results

For in-hospital death, the AUC were 0.67 for TIMI RS, 0.73 for GRACE RS, and 0.79 for SOFA score (P < 0.001, respectively). However, the SOFA score and GRACE RS were significantly better for predicting the 1-year (P < 0.001, respectively) and 3-year (P < 0.001, respectively) mortality than the TIMI RS was. Multivariate Cox regression analysis revealed that the SOFA score was an independent predictor of long-term mortality in AMI patients [hazard ratio (HR), 1.313; 95% CI, 1.191–1.447].

Conclusions

The SOFA score provides potentially valuable prognostic information on clinical outcome when applied to patients with AMI. Compared with TIMI RS, both SOFA score and GRACE RS provide better discrimination for long-term mortality in patients presenting with AMI.     

Acute kidney injury in critical care: Experience of a conservative strategy

Purpose

Renal replacement therapy (RRT) is a major supportive treatment of acute kidney injury (AKI) in intensive care unit (ICU), but the timing of its initiation remains open to debate.

Materials and methods

We retrospectively analyzed ICU patients who had AKI associated with at least one usual RRT criteria: serum creatinine concentration greater than 300 μmol/L, serum urea concentration greater than 25 mmol/L, serum potassium concentration greater than 6.5 mmol/L, severe metabolic acidosis (arterial blood pH < 7.2), oliguria (urine output < 135 mL/8 hours or < 400 mL/24 hours), overload pulmonary edema. To estimate the risk of death associated with RRT adjusted for risk factors, we performed a marginal structural Cox model with inverse-probability-of-treatment-weighted estimator.

Results

Among 4173 patients admitted to the ICU, 203 patients fulfilled potential RRT criteria. Ninety-one patients (44.8%) received RRT and 112 (55.2%) did not. Non-RRT and RRT patients differed in terms of severity of illness: Simplified Acute Physiology Score II (55 ± 17 vs 60 ± 19, respectively; P < .05) and Sequential Organ Failure Assessment score (8 [5-10] vs 9 [7-11], respectively; P = .01).Crude analysis indicated a lower ICU mortality for non-RRT compared with RRT patients (18% vs 45%; P < .001). In the marginal structural Cox model, RRT was associated with increased mortality (P < .01).

Conclusion

A conservative approach of AKI was not associated with increased mortality.     

Plasma neutrophil gelatinase-associated lipocalin as a biomarker for acute kidney injury in critically ill patients with suspected sepsis

Objectives

The aim of this study was to investigate the diagnostic utility of plasma neutrophil gelatinase-associated lipocalin (NGAL) as an early objective biomarker to predict acute kidney injury (AKI) in critically ill patients with suspected sepsis, for whom procalcitonin (PCT) was used for the diagnosis and staging of sepsis.

Design and methods

Plasma NGAL was measured using the Triage NGAL Test (Alere, Inc., San Diego, CA, USA) in 231 samples obtained from patients with suspected sepsis. The results of NGAL were compared with those of Elecsys BRAHMS PCT (Roche Diagnostics, Basel, Switzerland). Renal failure was assessed using the renal subscore of Sepsis-related Organ Failure Assessment (SOFA) score. AKI was defined according to the Acute Kidney Injury Network criteria.

Results

The concentrations of plasma NGAL were significantly different according to the five groups of PCT concentration (P < 0.0001) and the renal subscore of SOFA score (P < 0.0001). Plasma NGAL was significantly increased in the patients with AKI compared with those without AKI (416.5 ng/mL vs. 181.0 ng/mL, P = 0.0223).

Conclusion

Plasma NGAL seems to be a highly sensitive and objective predictor of AKI in patients with sepsis. Plasma NGAL can be added for the diagnosis and staging of renal failure in sepsis.     

Effect of N-acetylcysteine (NAC) on acute lung injury and acute kidney injury in hemorrhagic shock

Aim of the study

N-acetylcysteine (NAC) has been investigated to attenuate organ injury in various experimental and clinical studies. However, results in hemorrhagic shock (HS) were controversial. We determined the effects of continuous administration of NAC on acute lung injury (ALI) and acute kidney injury (AKI) in HS model.

Methods

Twenty male Sprague-Dawley rats were used. Pressure controlled HS model defined by mean arterial pressure (MAP) 40 ± 2 mmHg for 90 min followed by resuscitation and observation was used. Rats (n = 10 per group) were randomized into 2 groups with NAC or dextrose. Intravenous NAC was given continuously from 15 min after induction of HS to the end of observation period (2 h). We measured serum IL-6, nitrite/nitrate concentration. NF-κB p65 DNA binding activity, expressions of cytoplasmic phosphorylated IκB-α (p-IκB-α) and IκB-α, malondialdehyde (MDA) and histopathological injury scores in lung and kidney were also evaluated.

Results

MAP did not show any difference during the study period. NAC decreased histopathologic scores in both lung and kidney. Lung and kidney MDA levels were significantly lower in the NAC group compared to control group. Serum nitrite/nitrate and IL-6 were also significantly lower in the NAC group. The levels of lung cytoplasmic p-IκB-α expression was mitigated by NAC, and NF-κB p65 DNA binding activity was also significantly decreased in the NAC group.

Conclusions

Continuous infusion of NAC attenuated inflammatory response and acute lung and kidney injury after hemorrhagic shock in rats.     

Prediction of the renal replacement therapy requirement in mechanically ventilated critically ill patients by combining biomarkers for glomerular filtration and tubular damage

Purpose

Mechanically ventilated critically ill patients with high severity score indices need a very cautious therapeutic approach. Considering that inappropriate decisions on renal replacement therapy (RRT) initiation may promote unwanted adverse effects, we evaluated whether a panel of novel and traditional renal markers is superior to conventional renal marker in predicting RRT requirements in this group of patients.

Methods

This was a prospective observational study, performed at the two distinct multidisciplinary intensive care units (ICUs) of a 1000-bed tertiary hospital. Of 310 consecutive patients, 106 patients fulfilled the inclusion criteria of the study. Urinary neutrophil gelatinase–associated lipocalin (uNGAL), serum creatinine (sCr) and serum cystatin C (sCysC) were determined on ICU admission. The predictive performance of all markers for first RRT was tested and compared based on the area under the receiver operating characteristic (ROC) curves. Time-dependent ROC curves were used to assess the earlier time point where the markers presented their maximum area under the curve (AUC).

Results

All studied biomarkers and acute physiology and chronic health evaluation (APACHE) II score, were significant independent predictors of RRT (uNGAL-AUC = 0.73, sCysC-AUC = 0.76, sCr-AUC = 0.78, APACHE-AUC = 0.73, P < 0.0001). sCysC and sCr showed early maximum predictive ability within 10 days of ICU admission, while uNGAL and APACHE II score within 11 days of ICU admission. sCr combined with normalized (n)NGAL and sCysC combined with either nNGAL or uNGAL established best predictors for the RRT initiation (AUC-ROC = 0.8). Distinguishing patients without acute kidney injury (AKI) on ICU entry, the combination of sCysC and APACHE II score proved best (AUC-ROC = 0.78).

Conclusions

Specific markers of kidney dysfunction and of kidney damage can be successfully combined to increase the prognostic capability for RRT initiation. The presence of AKI affects diagnostic performance. Without an established AKI on ICU admission, future RRT requirement was better predicted by the combination of illness severity with a marker of glomerular filtration rate. With AKI on ICU admission a combination of the marker of glomerular filtration rate with one of tubular injury proved best.     

Association between transient acute kidney injury and morbidity and mortality after lung transplantation: A retrospective cohort study

Purpose

Acute kidney injury (AKI) is a common occurrence after lung transplantation (LTx). Whether transient AKI or early recovery is associated with improved outcome is uncertain. Our aim was to describe the incidence, factors, and outcomes associated with transient AKI after LTx.

Materials and Methods

We performed a retrospective cohort study of all adult recipients of LTx at the University of Alberta between 1990 and 2011. Our primary outcome transient AKI was defined as return of serum creatinine below Kidney Disease–Improving Global Outcome AKI stage I within 7 days after LTx. Secondary outcomes included occurrence of postoperative complications, mortality, and long-term kidney function.

Results

Of 445 LTx patients enrolled, AKI occurred in 306 (68.8%) within the first week after LTx. Of these, transient AKI (or early recovery) occurred in 157 (51.3%). Transient AKI was associated with fewer complications including tracheostomy (17.2% vs 38.3%; P < .001), reintubation (16.4% vs 41.9%; P < .001), decreased duration of mechanical ventilation (median [interquartile range], 69 [41-142] vs 189 [63-403] hours; P < .001), and lower rates of chronic kidney disease at 3 months (28.5% vs 51.1%, P < .001) and 1 year (49.6% vs 66.7%, P = .01) compared with persistent AKI. Factors independently associated with persistent AKI were higher body mass index (per unit; odds ratio [OR], 0.91; 95% confidence interval, 0.85-0.98; P = .01), cyclosporine use (OR, 0.29; 0.12-0.67; P = .01), longer duration of mechanical ventilation (per hour [log transformed]; OR, 0.42; 0.21-0.81; P = .01), and AKI stages II to III (OR, 0.16; 0.08-0.29; P < .001). Persistent AKI was associated with higher adjusted hazard of death (hazard ratio, 1.77 [1.08-2.93]; P = .02) when compared with transient AKI (1.44 [0.93-2.19], P = .09) and no AKI (reference category), respectively.

Conclusions

Transient AKI after LTx is associated with fewer complications and improved survival. Among survivors, persistent AKI portends an increased risk for long-term chronic kidney disease.     

Prognostic indicators of patients with acute kidney injury in intensive care unit

BACKGROUND:

Acute kidney injury (AKI) is associated with a high mortality. This study was undertaken to detect the factors associated with the prognosis of AKI.

METHODS:

We retrospectively reviewed 98 patients with AKI treated from March 2008 to August 2009 at this hospital. In these patients, 60 were male and 38 female. Their age ranged from 19 to 89 years (mean 52.4±16.1 years). The excluded patients were those who died within 24 hours after admission to ICU or those who had a history of chronic kidney disease or incomplete data. After 60 days of treatment, the patients were divided into a survival group and a death group. Clinical data including gender, age, history of chronic diseases, the worst laboratory values within 24 hours after diagnosis (values of routine blood tests, blood gas analysis, liver and renal function, levels of serum cystatin C, and blood electrolytes) were analyzed. Acute physiology, chronic health evaluation (APACHE) II scores and 60-day mortality were calculated. Univariate analysis was performed to find variables relevant to prognosis, odds ratio (OR) and 95% confidence interval (CI). Multiple-factor analysis with logistic regression analysis was made to analyze the correlation between risk factors and mortality.

RESULTS:

The 60-day mortality was 34.7% (34/98). The APACHE II score of the death group was higher than that of the survival group (17.4±4.3 vs. 14.2±4.8, P<0.05). The mortality of the patients with a high level of cystatin C>1.3 mg/L was higher than that of the patients with a low level of cystatin C (<1.3 mg/L) (50% vs. 20%, P<0.05). The univariate analysis indicated that organ failures≥2, oliguria, APACHE II>15 scores, cystatin C>1.3 mg/L, cystatin C>1.3 mg/L+APACHE II>15 scores were the risk factors of AKI. Logistic regression analysis, however, showed that organ failures≥2, oliguria, cystatin C>1.3 mg/L +APACHE II>15 scores were the independent risk factors of AKI.

CONCLUSION:

Cystatin C>1.3 mg/L+APACHE II>15 scores is useful in predicting adverse clinical outcomes in patients with AKI.KEY WORDS: Intensive care unit, Acute kidney injury, Serum cystatin C, APACHE II, Oliguria, Retrospective studies, Prognosis     

Determinants of renal function at hospital discharge of patients treated with renal replacement therapy in the intensive care unit

Purpose

Identification of risk factors for impaired renal function at hospital discharge in critically ill patients with acute kidney injury (AKI) requiring renal replacement therapy (RRT).

Methods

A single-center retrospective cohort study was performed evaluating demographic and clinical parameters as potential risk factors for a modest to severely impaired renal function at hospital discharge in patients with AKI requiring RRT in the intensive care unit.

Results

Of the 353 patients in our cohort, 90 (25.5%) patients had pre-existing chronic kidney disease (CKD). An estimated glomerular filtration rate (eGFR) ≤ 60 mL min^− 1 1.73 m^− 2 at hospital discharge occurred in 64.0% of which 63.7% without known renal impairment before hospital admission and 8.2% of all cases left the hospital dialysis-dependent. Multivariable logistic regression showed that age (OR = 1.051, P < .001), serum creatinine concentration at start of RRT (OR = 1.004, P < .001) and administration of iodine-containing contrast fluid (OR = 0.830, P = .045) were associated with an eGFR ≤ 60 mL min^− 1 1.73 m^− 2. Furthermore, a medical history of CKD (OR = 5.865, P < .001) was associated with dialysis dependence.

Conclusions

Elderly and patients with pre-existing CKD are at a high risk for modest to severely impaired renal function at hospital discharge after AKI requiring RRT.     

Initial serum glucose level and white blood cell predict ventricular arrhythmia after first acute myocardial infarction

Objective

The aims of this study are to analyze the factors that predispose the occurrence of ventricular arrhythmia (VA) in young patients with a first acute myocardial infarction (AMI) in the emergency department (ED) and to establish predictive implications.

Methods

This is a 10-year retrospective cohort study. Patients who were older than 18 years and younger than 45 years with a first attack of AMI were recruited from the ED of 3 university teaching hospitals from January 1, 1998, to December 31, 2007.

Results

Five hundred young patients (472 men and 28 women) who met the inclusion criteria were enrolled. Within these patients, the incidence of life-threatening VA with first attack of AMI was 8% (n = 40). They were categorized into 2 groups: VA attack (n = 40) and non-VA attack (n = 460). In univariable analyses, acute anterolateral ST-segment elevation myocardial infarction (65% vs 47.8%; P = .04), elevate white blood cell (WBC) count (16.4 ± 3.4 vs 11.5 ± 3.1 × 10³/mm³; P < .01), and initial serum glucose level (202.6 ± 90.9 vs 151.9 ± 64.7 mg/dL; P < .01) were significantly increased in the VA group. Multiple logistic regression model identified WBC count and initial serum glucose level as the significant independent variables in the prediction of VA attack for young patients with first attack of AMI. The receiver operating characteristic area for WBC count and serum glucose level in predicting the risk of VA occurring after AMI was 0.869 and 0.756, respectively.

Conclusion

Initial serum glucose level and WBC may be used as valuable predictors for VA attack in young patients with first AMI.     

Early initiation of continuous renal replacement therapy improves patient survival in severe progressive septic acute kidney injury

Purpose

The definition of “early” in terms of continuous renal replacement therapy (CRRT) initiation has not been uniformly used. Therefore, we tried to elucidate whether the timing of CRRT application, based on the interval between the start time of vasopressors infusion and CRRT initiation, was an independent predictor of mortality in the patients with septic acute kidney injury (AKI).

Materials and Methods

Progressive septic AKI patients, in whom the infusion doses of vasopressors were increased compared with the initial dose during the first 6 hours of vasopressor treatment and CRRT was performed, between 2009 and 2011, were collected and divided into 2 groups based on the median interval between the 2 points.

Results

A total of 210 patients were included. The mean age was 62.4 years, and 126 patients (60.0%) were male. The most common comorbid disease was malignancy (53.8%), followed by hypertension (35.7%) and diabetes mellitus (29.0%). The median interval between the start time of vasopressor infusion and CRRT commencement was 2.0 days. During the study period, 156 patients (74.3%) died within 28 days of CRRT application. The interval between 2 points was significantly shorter in the survivor compared with the death group (P < .001). Moreover, 28-day overall mortality rates in the early CRRT group were significantly lower than those in the late CRRT group (P = .034). Furthermore, early CRRT treatment was independently associated with a lower mortality rate even after adjustment for age, sex, causative organisms, and infection sites (P = .032).

Conclusions

This retrospective cohort study suggests that early initiation of CRRT may be of benefit. Given the complex nature of this intervention, the ongoing controversies regarding early vs late initiation of therapy in acute and chronic situation, there is an urgent need to develop well-designed clinical trials to answer the question definitely.     

Acute kidney injury after cardiac arrest

Aim

Cardiac arrest (CA) in humans causes warm renal ischemia-reperfusion injury, similar to animal models of ischemic acute kidney injury (AKI). We aimed to investigate the incidence and risk associations of AKI after CA, with or without post-resuscitation cardiogenic shock (PRCS).

Methods

We examined the renal outcomes of adult patients admitted to the intensive care unit (ICU), who survived for more than 48 h following successful resuscitation after CA.

Results

Of 105 patients (median age 65 years; 69% male), 58 (55.2%) had PRCS and were on vasoactive drugs beyond 24 h; and 9 (8.6%) (all of whom had PRCS) received renal replacement therapy. Only 3 (6.4%) of 47 patients without PRCS had RIFLE-‘I’/‘F’ AKI, compared to 30 (51.7%) of 58 patients with PRCS (p < 0.001). Median peak serum creatinine in the non-PRCS group was 102 μmol/L (interquartile range 85–115), compared to 155 μmol/L (interquartile range 112–267) (p < 0.001) in the PRCS group. On multivariate analysis, cumulative noradrenaline dose during the first 24 h in ICU, PRCS, and pre-CA renin–angiotensin–aldosterone-system blockade were independently associated with RIFLE-‘I’/‘F’ AKI; while higher serum lactate 12 h after CA, baseline creatinine, and PRCS were independently associated with greater rise in creatinine from pre-CA levels. Estimated time without spontaneous circulation, total adrenaline dose and initial cardiac rhythm during CA, had no independent associations with renal outcomes.

Conclusions

In the absence of PRCS, CA in isolation is uncommonly associated with significant AKI. The human kidney may be more resistant to warm ischemia-reperfusion injury than previously thought.