Incidence and Mortality of Acute Kidney Injury after Myocardial Infarction: A Comparison between KDIGO and RIFLE Criteria

Background

Acute kidney injury (AKI) increases the risk of death after acute myocardial infarction (AMI). Recently, a new AKI definition was proposed by the Kidney Disease Improving Global Outcomes (KDIGO) organization. The aim of the current study was to compare the incidence and the early and late mortality of AKI diagnosed by RIFLE and KDIGO criteria in the first 7 days of hospitalization due to an AMI.

Methods and Results

In total, 1,050 AMI patients were prospectively studied. AKI defined by RIFLE and KDIGO occurred in 14.8% and 36.6% of patients, respectively. By applying multivariate Cox analysis, AKI was associated with an increased adjusted hazard ratio (AHR) for 30-day death of 3.51 (95% confidence interval [CI] 2.35–5.25, p<0.001) by RIFLE and 3.99 (CI 2.59–6.15, p<0.001) by KDIGO and with an AHR for 1-year mortality of 1.84 (CI 1.12–3.01, p = 0.016) by RIFLE and 2.43 (CI 1.62–3.62, p<0.001) by KDIGO. The subgroup of patients diagnosed as non-AKI by RIFLE but as AKI by KDIGO criteria had also an increased AHR for death of 2.55 (1.52–4.28) at 30 days and 2.28 (CI 1.46–3.54) at 1 year (p<0.001).

Conclusions

KDIGO criteria detected substantially more AKI patients than RIFLE among AMI patients. Patients diagnosed as AKI by KDIGO but not RIFLE criteria had a significantly higher early and late mortality. In this study KDIGO criteria were more suitable for AKI diagnosis in AMI patients than RIFLE criteria.     

Renal function at hospital admission and mortality due to acute kidney injury after myocardial infarction

Background

The role of an impaired estimated glomerular filtration rate (eGFR) at hospital admission in the outcome of acute kidney injury (AKI) after acute myocardial infarction (AMI) has been underreported. The aim of this study was to assess the influence of an admission eGFR<60 mL/min/1.73 m² on the incidence and early and late mortality of AMI-associated AKI.

Methods

A prospective study of 828 AMI patients was performed. AKI was defined as a serum creatinine increase of ≥50% from the time of admission (RIFLE criteria) in the first 7 days of hospitalization. Patients were divided into subgroups according to their eGFR upon hospital admission (MDRD formula, mL/min/1.73 m²) and the development of AKI: eGFR≥60 without AKI, eGFR<60 without AKI, eGFR≥60 with AKI and eGFR<60 with AKI.

Results

Overall, 14.6% of the patients in this study developed AKI. The admission eGFR had no impact on the incidence of AKI. However, the admission eGFR was associated with the outcome of AMI-associated AKI. The adjusted hazard ratios (AHR, Cox multivariate analysis) for 30-day mortality were 2.00 (95% CI 1.11–3.61) for eGFR<60 without AKI, 4.76 (95% CI 2.45–9.26) for eGFR≥60 with AKI and 6.27 (95% CI 3.20–12.29) for eGFR<60 with AKI. Only an admission eGFR of <60 with AKI was significantly associated with a 30-day to 1-year mortality hazard (AHR 3.05, 95% CI 1.50–6.19).

Conclusions

AKI development was associated with an increased early mortality hazard in AMI patients with either preserved or impaired admission eGFR. Only the association of impaired admission eGFR and AKI was associated with an increased hazard for late mortality among these patients.     

Nephrology Referral and Outcomes in Critically Ill Acute Kidney Injury Patients

Background

Delayed nephrology consultation (NC) seems to be associated with worse prognosis in critically ill acute kidney injury (AKI) patients.

Design, Setting, Participants, & Measurements

The aims of this study were to analyze factors related with timing of NC and its relation with AKI patients'' outcome in intensive care units of a tertiary hospital. AKI was defined as an increase ≥50% in baseline serum creatinine (SCr). Early NC and delayed NC were defined as NC performed before and two days after AKI diagnosis day. Multivariable logistic regression and propensity scores (PS) were used to adjust for confounding and selection biases. Hospital mortality and dialysis dependence on hospital discharge were the primary outcomes.

Results

A total of 366 AKI patients were analyzed and NCs were carried out in 53.6% of the patients. Hospital mortality was 67.8% and dialysis required in 31.4% patients (115/366). Delayed NCs (34%) occurred two days after AKI diagnosis day. This group presented higher mortality (OR: 4.04/CI: 1.60–10.17) and increased dialysis dependence (OR: 3.00/CI: 1.43–6.29) on hospital discharge. Four variables were retained in the PS model for delayed NC: diuresis (1000 ml/24 h - OR: 1.92/CI: 1.27–2.90), SCr (OR: 0.49/CI: 0.32–0.75), surgical AKI (OR: 3.67/CI: 1.65–8.15), and mechanical ventilation (OR: 2.82/CI: 1.06–7.44). After correction by PS, delayed NC was still associated with higher mortality (OR: 3.39/CI: 1.24–9.29) and increased dialysis dependence (OR: 3.25/CI: 1.41–7.51). Delayed NC was associated with increased mortality either in dialyzed patients (OR: 1.54/CI: 1.35–1.78) or non-dialyzed patients (OR: 2.89/CI: 1.00–8.35).

Conclusion

Delayed NC was associated with higher mortality and increased dialysis dependence rates in critically ill AKI patients at hospital discharge. Further studies are necessary to ascertain whether this effect is due to delayed nephrology intervention or residual confounding factors.     

Identification and Predicting Short-Term Prognosis of Early Cardiorenal Syndrome Type 1: KDIGO Is Superior to RIFLE or AKIN

Objective

Acute kidney injury (AKI) in patients hospitalized for acute heart failure (AHF) is usually type 1 of the cardiorenal syndrome (CRS) and has been associated with increased morbidity and mortality. Early recognition of AKI is critical. This study was to determine if the new KDIGO criteria (Kidney Disease: Improving Global Outcomes) for identification and short-term prognosis of early CRS type 1 was superior to the previous RIFLE and AKIN criteria.

Methods

The association between AKI diagnosed by KDIGO but not by RIFLE or AKIN and in-hospital mortality was retrospectively evaluated in 1005 Chinese adult patients with AHF between July 2008 and May 2012. AKI was defined as RIFLE, AKIN and KDIGO criteria, respectively. Cox regression was used for multivariate analysis of in-hospital mortality.

Results

Within 7 days on admission, the incidence of CRS type 1 was 38.9% by KDIGO criteria, 34.7% by AKIN, and 32.1% by RIFLE. A total of 110 (10.9%) cases were additional diagnosed by KDIGO criteria but not by RIFLE or AKIN. 89.1% of them were in Stage 1 (AKIN) or Stage Risk (RIFLE). They accounted for 18.4% (25 cases) of the overall death. After adjustment, this proportion remained an independent risk factor for in-hospital mortality [odds ratios (OR)3.24, 95% confidence interval(95%CI) 1.97–5.35]. Kaplan-Meier curve showed AKI patients by RIFLE, AKIN, KDIGO and [K(+)R(−)+K(+)A(−)] had lower hospital survival than non-AKI patients (Log Rank P<0.001).

Conclusion

KDIGO criteria identified significantly more CRS type 1 episodes than RIFLE or AKIN. AKI missed diagnosed by RIFLE or AKIN criteria was an independent risk factor for in-hospital mortality, indicating the new KDIGO criteria was superior to RIFLE and AKIN in predicting short-term outcomes in early CRS type 1.     

Urinary Biomarkers Indicative of Apoptosis and Acute Kidney Injury in the Critically Ill

Background

Apoptosis is a key mechanism involved in ischemic acute kidney injury (AKI), but its role in septic AKI is controversial. Biomarkers indicative of apoptosis could potentially detect developing AKI prior to its clinical diagnosis.

Methods

As a part of the multicenter, observational FINNAKI study, we performed a pilot study among critically ill patients who developed AKI (n = 30) matched to critically ill patients without AKI (n = 30). We explored the urine and plasma levels of cytokeratin-18 neoepitope M30 (CK-18 M30), cell-free DNA, and heat shock protein 70 (HSP70) at intensive care unit (ICU) admission and 24h thereafter, before the clinical diagnosis of AKI defined by the Kidney Disease: Improving Global Outcomes -creatinine and urine output criteria. Furthermore, we performed a validation study in 197 consecutive patients in the FINNAKI cohort and analyzed the urine sample at ICU admission for CK-18 M30 levels.

Results

In the pilot study, the urine or plasma levels of measured biomarkers at ICU admission, at 24h, or their maximum value did not differ significantly between AKI and non-AKI patients. Among 20 AKI patients without severe sepsis, the urine CK-18 M30 levels were significantly higher at 24h (median 116.0, IQR [32.3–233.0] U/L) than among those 20 patients who did not develop AKI (46.0 [0.0–54.0] U/L), P = 0.020. Neither urine cell-free DNA nor HSP70 levels significantly differed between AKI and non-AKI patients regardless of the presence of severe sepsis. In the validation study, urine CK-18 M30 level at ICU admission was not significantly higher among patients developing AKI compared to non-AKI patients regardless of the presence of severe sepsis or CKD.

Conclusions

Our findings do not support that apoptosis detected with CK-18 M30 level would be useful in assessing the development of AKI in the critically ill. Urine HSP or cell-free DNA levels did not differ between AKI and non-AKI patients.     

Dialysis-Requiring Acute Kidney Injury in Denmark 2000-2012: Time Trends of Incidence and Prevalence of Risk Factors—A Nationwide Study

Introduction

Dialysis-requiring acute kidney injury is a severe illness associated with poor prognosis. However, information pertaining to incidence rates and prevalence of risk factors remains limited in spite of increasing focus. We evaluate time trends of incidence rates and changing patterns in prevalence of comorbidities, concurrent medication, and other risk factors in nationwide retrospective cohort study.

Materials and Methods

All patients with dialysis-requiring acute kidney injury were identified between January 1^st 2000 and December 31^st 2012. By cross-referencing data from national administrative registries, the association of changing patterns in dialysis treatment, comorbidity, concurrent medication and demographics with incidence of dialysis-requiring acute kidney injury was evaluated.

Results

A total of 18,561 adult patients with dialysis-requiring AKI were identified between 2000 and 2012. Crude incidence rate of dialysis-requiring AKI increased from 143 per million (95% confidence interval, 137–144) in 2000 to 366 per million (357–375) in 2006, and remained stable hereafter. Notably, incidence of continuous veno-venous hemodialysis (CRRT) and use of acute renal replacement therapy in elderly >75 years increased substantially from 23 per million (20–26) and 328 per million (300–355) in 2000, to 213 per million (206–220) and 1124 per million (1076–1172) in 2012, respectively. Simultaneously, patient characteristics and demographics shifted towards increased age and comorbidity.

Conclusions

Although growth in crude incidence rate of dialysis-requiring AKI stabilized in 2006, continuous growth in use of CRRT, and acute renal replacement therapy of elderly patients >75 years, was observed. Our results indicate an underlying shift in clinical paradigm, as opposed to unadulterated growth in incidence of dialysis-requiring AKI.     

Urinary Tissue Inhibitor of Metalloproteinase-2 (TIMP-2) ? Insulin-Like Growth Factor-Binding Protein 7 (IGFBP7) Predicts Adverse Outcome in Pediatric Acute Kidney Injury

Background

The G1 cell cycle inhibitors tissue inhibitor of metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) have been identified as promising biomarkers for the prediction of adverse outcomes including renal replacement therapy (RRT) and mortality in critically ill adult patients who develop acute kidney injury (AKI). However, the prognostic value of urinary TIMP-2 and IGFBP7 in neonatal and pediatric AKI for adverse outcome has not been investigated yet.

Methods

The product of the urinary concentration of TIMP-2 and IGFBP7 ([TIMP-2]•[IGFBP7]) was assessed by a commercially available immunoassay (NephroCheck^™) in a prospective cohort study in 133 subjects aged 0–18 years including 46 patients with established AKI according to pRIFLE criteria, 27 patients without AKI (non-AKI group I) and 60 apparently healthy neonates and children (non-AKI group II). AKI etiologies were: dehydration/hypovolemia (n = 7), hemodynamic instability (n = 7), perinatal asphyxia (n = 9), septic shock (n = 7), typical hemolytic-uremic syndrome (HUS; n = 5), interstitial nephritis (n = 5), vasculitis (n = 4), nephrotoxic injury (n = 1) and renal vein thrombosis (n = 1).

Results

When AKI patients were classified into pRIFLE criteria, 6/46 (13%) patients fulfilled the criteria for the category “Risk”, 13/46 (28%) for “Injury”, 26/46 (57%) for “Failure” and 1/46 (2%) for “Loss”. Patients in the “Failure” stage had a median 3.7-fold higher urinary [TIMP-2]•[IGFBP7] compared to non-AKI subjects (P<0.001). When analyzed for AKI etiology, highest [TIMP-2]•[IGFBP7] values were found in patients with septic shock (P<0.001 vs. non-AKI I+II). Receiver operating characteristic (ROC) curve analyses in the AKI group revealed good performance of [TIMP-2]•[IGFBP7] in predicting 30-day (area under the curve (AUC) 0.79; 95% CI, 0.61–0.97) and 3-month mortality (AUC 0.84; 95% CI, 0.67–0.99) and moderate performance in predicting RRT (AUC 0.67; 95% CI, 0.50–0.84).

Conclusions

This study shows that urinary [TIMP-2]•[IGFBP7] has a good diagnostic performance in predicting adverse outcomes in neonatal and pediatric AKI of heterogeneous etiology.     

Risk Factors for Acute Kidney Injury and In-Hospital Mortality in Patients Receiving Extracorporeal Membrane Oxygenation

Background and Objectives

Although acute kidney injury (AKI) is the most frequent complication in patients receiving extracorporeal membrane oxygenation (ECMO), few studies have been conducted on the risk factors of AKI. We performed this study to identify the risk factors of AKI associated with in-hospital mortality.

Methods

Data from 322 adult patients receiving ECMO were analyzed. AKI and its stages were defined according to Kidney Disease Improving Global Outcomes (KDIGO) classifications. Variables within 24 h before ECMO insertion were collected and analyzed for the associations with AKI and in-hospital mortality.

Results

Stage 3 AKI was associated with in-hospital mortality, with a hazard ratio (HR) (95% CI) of 2.690 (1.472–4.915) compared to non-AKI (p = 0.001). The simplified acute physiology score 2 (SAPS2) and serum sodium level were also associated with in-hospital mortality, with HRs of 1.02 (1.004–1.035) per 1 score increase (p = 0.01) and 1.042 (1.014–1.070) per 1 mmol/L increase (p = 0.003). The initial pump speed of ECMO was significantly related to in-hospital mortality with a HR of 1.333 (1.020–1.742) per 1,000 rpm increase (p = 0.04). The pump speed was also associated with AKI (p = 0.02) and stage 3 AKI (p = 0.03) with ORs (95% CI) of 2.018 (1.129–3.609) and 1.576 (1.058–2.348), respectively. We also found that the red cell distribution width (RDW) above 14.1% was significantly related to stage 3 AKI.

Conclusion

The initial pump speed of ECMO was a significant risk factor of in-hospital mortality and AKI in patients receiving ECMO. The RDW was a risk factor of stage 3 AKI.     

The Real Importance of Pre-Existing Comorbidities on Long-Term Mortality after Acute Kidney Injury

Background

The causes of death on long-term mortality after acute kidney injury (AKI) have not been well studied. The purpose of the study was to evaluate the role of comorbidities and the causes of death on the long-term mortality after AKI.

Methodology/Principal Findings

We retrospectively studied 507 patients who experienced AKI in 2005–2006 and were discharged free from dialysis. In June 2008 (median: 21 months after AKI), we found that 193 (38%) patients had died. This mortality is much higher than the mortality of the population of São Paulo City, even after adjustment for age. A multiple survival analysis was performed using Cox proportional hazards regression model and showed that death was associated with Khan’s index indicating high risk [adjusted hazard ratio 2.54 (1.38–4.66)], chronic liver disease [1.93 (1.15–3.22)], admission to non-surgical ward [1.85 (1.30–2.61)] and a second AKI episode during the same hospitalization [1.74 (1.12–2.71)]. The AKI severity evaluated either by the worst stage reached during AKI (P = 0.20) or by the need for dialysis (P = 0.12) was not associated with death. The causes of death were identified by a death certificate in 85% of the non-survivors. Among those who died from circulatory system diseases (the main cause of death), 59% had already suffered from hypertension, 34% from diabetes, 47% from heart failure, 38% from coronary disease, and 66% had a glomerular filtration rate <60 previous to the AKI episode. Among those who died from neoplasms, 79% already had the disease previously.

Conclusions

Among AKI survivors who were discharged free from dialysis the increased long-term mortality was associated with their pre-existing chronic conditions and not with the severity of the AKI episode. These findings suggest that these survivors should have a medical follow-up after hospital discharge and that all efforts should be made to control their comorbidities.     

Increased Risk of Active Tuberculosis following Acute Kidney Injury: A Nationwide,Population-Based Study

Background

Profound alterations in immune responses associated with uremia and exacerbated by dialysis increase the risk of active tuberculosis (TB). Evidence of the long-term risk and outcome of active TB after acute kidney injury (AKI) is limited.

Methods

This population-based-cohort study used claim records retrieved from the Taiwan National Health Insurance database. We retrieved records of all hospitalized patients, more than 18 years, who underwent dialysis for acute kidney injury (AKI) during 1999–2008 and validated using the NSARF data. Time-dependent Cox proportional hazards model to adjust for the ongoing effect of end-stage renal disease (ESRD) was conducted to predict long-term de novo active TB after discharge from index hospitalization.

Results

Out of 2,909 AKI dialysis patients surviving 90 days after index discharge, 686 did not require dialysis after hospital discharge. The control group included 11,636 hospital patients without AKI, dialysis, or history of TB. The relative risk of active TB in AKI dialysis patients, relative to the general population, after a mean follow-up period of 3.6 years was 7.71. Patients who did (hazard ratio [HR], 3.84; p<0.001) and did not (HR, 6.39; p<0.001) recover from AKI requiring dialysis had significantly higher incidence of TB than patients without AKI. The external validated data also showed nonrecovery subgroup (HR = 4.37; p = 0.049) had high risk of developing active TB compared with non-AKI. Additionally, active TB was associated with long-term all-cause mortality after AKI requiring dialysis (HR, 1.34; p = 0.032).

Conclusions

AKI requiring dialysis seems to independently increase the long-term risk of active TB, even among those who weaned from dialysis at discharge. These results raise concerns that the increasing global burden of AKI will in turn increase the incidence of active TB.     

Mortality Predictors in Renal Transplant Recipients with Severe Sepsis and Septic Shock

Introduction

The growing number of renal transplant recipients in a sustained immunosuppressive state is a factor that can contribute to increased incidence of sepsis. However, relatively little is known about sepsis in this population. The aim of this single-center study was to evaluate the factors associated with hospital mortality in renal transplant patients admitted to the intensive care unit (ICU) with severe sepsis and septic shock.

Methods

Patient demographics and transplant-related and ICU stay data were retrospectively collected. Multiple logistic regression was conducted to identify the independent risk factors associated with hospital mortality.

Results

A total of 190 patients were enrolled, 64.2% of whom received kidneys from deceased donors. The mean patient age was 51±13 years (males, 115 [60.5%]), and the median APACHE II was 20 (16–23). The majority of patients developed sepsis late after the renal transplantation (2.1 [0.6–2.3] years). The lung was the most common infection site (59.5%). Upon ICU admission, 16.4% of the patients had ≤1 systemic inflammatory response syndrome criteria. Among the patients, 61.5% presented with ≥2 organ failures at admission, and 27.9% experienced septic shock within the first 24 hours of ICU admission. The overall hospital mortality rate was 38.4%. In the multivariate analysis, the independent determinants of hospital mortality were male gender (OR = 5.9; 95% CI, 1.7–19.6; p = 0.004), delta SOFA 24 h (OR = 1.7; 95% CI, 1.2–2.3; p = 0.001), mechanical ventilation (OR = 30; 95% CI, 8.8–102.2; p<0.0001), hematologic dysfunction (OR = 6.8; 95% CI, 2.0–22.6; p = 0.002), admission from the ward (OR = 3.4; 95% CI, 1.2–9.7; p = 0.02) and acute kidney injury stage 3 (OR = 5.7; 95% CI,1.9–16.6; p = 0.002).

Conclusions

Hospital mortality in renal transplant patients with severe sepsis and septic shock was associated with male gender, admission from the wards, worse SOFA scores on the first day and the presence of hematologic dysfunction, mechanical ventilation or advanced graft dysfunction.     

Incidence,Characteristics and Risk Factors of Acute Kidney Injury among Dengue Patients: A Retrospective Analysis

Background

Dengue induced acute kidney injury (AKI) imposes heavy burden of illness in terms of morbidity and mortality. A retrospective study was conducted to investigate incidence, characteristics, risk factors and clinical outcomes of AKI among dengue patients.

Methodology

A total 667 dengue patients (2008–2013) were retrospectively evaluated and were stratified into AKI and non-AKI groups by using AKIN criteria. Two groups were compared by using appropriate statistical methods.

Results

There were 95 patients (14.2%) who had AKI, with AKIN-I, AKIN-II and AKIN-III in 76.8%, 16.8% and 6.4% patients, respectively. Significant differences (P<0.05) in demographics and clinico-laboratory characteristics were observed between patients with and without AKI. Presence of dengue hemorrhagic fever [OR (95% CI): 8.0 (3.64–17.59), P<0.001], rhabdomyolysis [OR (95% CI): 7.9 (3.04–20.49)], multiple organ dysfunction [OR (95% CI): 34.6 (14.14–84.73), P<0.001], diabetes mellitus [OR (95% CI): 4.7 (1.12–19.86), P = 0.034], late hospitalization [OR (95% CI): 2.1 (1.12–19.86), P = 0.033] and use of nephrotoxic drugs [OR (95% CI): 2.9 (1.12–19.86), P = 0.006] were associated with AKI. Longer hospital stay (>3 days) was also observed among AKI patients (OR = 1.3, P = 0.044). Additionally, 48.4% AKI patients had renal insufficiencies at discharge that were signicantly associated with severe dengue, secondary infection and diabetes mellitus. Overall mortality was 1.2% and all fatal cases had AKI.

Conclusions

The incidence of AKI is high at 14.2% among dengue patients, and those with AKI portended significant morbidity, mortality, longer hospital stay and poor renal outcomes. Our findings suggest that AKI in dengue is likely to increase healthcare burden that underscores the need of clinicians’ alertness to this highly morbid and potentially fatal complication for optimal prevention and management.     

Impact of Hiv-Associated Conditions on Mortality in People Commencing Anti-Retroviral Therapy in Resource Limited Settings

Objectives

To identify associations between specific WHO stage 3 and 4 conditions diagnosed after ART initiation and all cause mortality for patients in resource-limited settings (RLS).

Design, Setting

Analysis of routine program data collected prospectively from 25 programs in eight countries between 2002 and 2010.

Subjects, Participants

36,664 study participants with median ART follow-up of 1.26 years (IQR 0.55–2.27).

Outcome Measures

Using a proportional hazards model we identified factors associated with mortality, including the occurrence of specific WHO clinical stage 3 and 4 conditions during the 6-months following ART initiation.

Results

There were 2922 deaths during follow-up (8.0%). The crude mortality rate was 5.41 deaths per 100 person-years (95% CI: 5.21–5.61). The diagnosis of any WHO stage 3 or 4 condition during the first 6 months of ART was associated with increased mortality (HR: 2.21; 95% CI: 1.97–2.47). After adjustment for age, sex, region and pre-ART CD4 count, a diagnosis of extrapulmonary cryptococcosis (aHR: 3.54; 95% CI: 2.74–4.56), HIV wasting syndrome (aHR: 2.92; 95%CI: 2.21 -3.85), non-tuberculous mycobacterial infection (aHR: 2.43; 95% CI: 1.80–3.28) and Pneumocystis pneumonia (aHR: 2.17; 95% CI 1.80–3.28) were associated with the greatest increased mortality. Cerebral toxoplasmosis, pulmonary and extra-pulmonary tuberculosis, Kaposi’s sarcoma and oral and oesophageal candidiasis were associated with increased mortality, though at lower rates.

Conclusions

A diagnosis of certain WHO stage 3 and 4 conditions is associated with an increased risk of mortality in those initiating ART in RLS. This information will assist initiatives to reduce excess mortality, including prioritization of resources for diagnostics, therapeutic interventions and research.     

Incidence and Characteristics of Acute Kidney Injury in Severe Diabetic Ketoacidosis

Aims

Acute kidney injury is a classical complication of diabetic ketoacidosis. However, to the best of our knowledge, no study has reported the incidence and characteristics of acute kidney injury since the consensus definition was issued.

Methods

Retrospective study of all cases of severe diabetic ketoacidosis hospitalised consecutively in a medical surgical tertiary ICU during 10 years. Patients were dichotomised in with AKI and without AKI on admission according to the RIFLE classification. Clinical and biological parameters were compared in these populations. Risk factors of presenting AKI on admission were searched for.

Results

Ninety-four patients were included in the study. According to the RIFLE criteria, 47 patients (50%) presented acute kidney injury on admission; most of them were in the risk class (51%). At 12 and 24 hours, the percentage of AKI patients decreased to 26% and 27% respectively. During the first 24 hours, 3 patients needed renal replacement therapy. Acute renal failure on admission was associated with a more advanced age, SAPS 2 and more severe biological impairments. Treatments were not different between groups except for insulin infusion. Logistic regression found 3 risk factors of presenting AKI on admission: age (odds ratio 1.060 [1.020–1.100], p<0.01), blood glucose (odds ratio 1.101 [1.039–1.166], p<0.01) and serum protein (odds ratio 0.928 [0.865–0.997], p = 0.04).

Conclusions

Acute kidney injury is frequently associated with severe diabetic ketoacidosis on admission in ICU. Most of the time, this AKI is transient and characterised by a volume-responsiveness to fluid infusion used in DKA treatment. Age, blood glucose and serum protein are associated to the occurrence of AKI on ICU admission.     

Diagnostic Value of Urinary Kidney Injury Molecule 1 for Acute Kidney Injury: A Meta-Analysis

Background

Urinary Kidney Injury Molecule 1 (KIM-1) is a proximal tubular injury biomarker for early detection of acute kidney injury (AKI), with variable performance characteristics depending on clinical and population settings.

Methods

Meta-analysis was performed to assess the diagnostic value of urinary KIM-1 in AKI. Relevant studies were searched from MEDLINE, EMBASE, Pubmed, Elsevier Science Direct, Scopus, Web of Science, Google Scholar and Cochrane Library. Meta-analysis methods were used to pool sensitivity and specificity and to construct summary receiver operating characteristic (SROC) curves.

Results

A total of 2979 patients from 11 eligible studies were enrolled in the analysis. Five prospective cohorts, two cross-sectional and four case-control studies were identified for meta-analysis. The estimated sensitivity of urinary KIM-1 for the diagnosis of AKI was 74.0% (95% CI, 61.0%–84.0%), and specificity was 86.0% (95% CI, 74.0%–93.0%). The SROC analysis showed an area under the curve of 0.86(0.83–0.89). Subgroup analysis suggested that population settings and detection time were the key factors affecting the efficiency of KIM-1 for AKI diagnosis.

Limitation

Various population settings, different definition of AKI and Serum creatinine level used as the standard might have influence on AKI diagnosis. The relatively small number of studies and heterogeneity between them also affected the evaluation.

Conclusion

Urinary KIM-1 may be a promising biomarker for early detection of AKI with considerable predictive value, especially for cardiac surgery patients, and its potential value needs to be validated in large studies and across a broader scope of clinical settings.     

Evaluation of Pneumonia Severity and Acute Physiology Scores to Predict ICU Admission and Mortality in Patients Hospitalized for Influenza

Background

The demand for inpatient medical services increases during influenza season. A scoring system capable of identifying influenza patients at low risk death or ICU admission could help clinicians make hospital admission decisions.

Methods

Hospitalized patients with laboratory confirmed influenza were identified over 3 influenza seasons at 25 Ontario hospitals. Each patient was assigned a score for 6 pneumonia severity and 2 sepsis scores using the first data available following their registration in the emergency room. In-hospital mortality and ICU admission were the outcomes. Score performance was assessed using the area under the receiver operating characteristic curve (AUC) and the sensitivity and specificity for identifying low risk patients (risk of outcome <5%).

Results

The cohort consisted of 607 adult patients. Mean age was 76 years, 12% of patients died (71/607) and 9% required ICU care (55/607). None of the scores examined demonstrated good discriminatory ability (AUC≥0.80). The Pneumonia Severity Index (AUC 0.78, 95% CI 0.72–0.83) and the Mortality in Emergency Department Sepsis score (AUC 0.77, 95% 0.71–0.83) demonstrated fair predictive ability (AUC≥0.70) for in-hospital mortality. The best predictor of ICU admission was SMART-COP (AUC 0.73, 95% CI 0.67–0.79). All other scores were poor predictors (AUC <0.70) of either outcome. If patients classified as low risk for in-hospital mortality using the PSI were discharged, 35% of admissions would have been avoided.

Conclusions

None of the scores studied were good predictors of in-hospital mortality or ICU admission. The PSI and MEDS score were fair predictors of death and if these results are validated, their use could reduce influenza admission rates significantly.     

The Effect of Hospital Volume on Mortality in Patients Admitted with Severe Sepsis

Importance

The association between hospital volume and inpatient mortality for severe sepsis is unclear.

Objective

To assess the effect of severe sepsis case volume and inpatient mortality.

Design Setting and Participants

Retrospective cohort study from 646,988 patient discharges with severe sepsis from 3,487 hospitals in the Nationwide Inpatient Sample from 2002 to 2011.

Exposures

The exposure of interest was the mean yearly sepsis case volume per hospital divided into tertiles.

Main Outcomes and Measures

Inpatient mortality.

Results

Compared with the highest tertile of severe sepsis volume (>60 cases per year), the odds ratio for inpatient mortality among persons admitted to hospitals in the lowest tertile (≤10 severe sepsis cases per year) was 1.188 (95% CI: 1.074–1.315), while the odds ratio was 1.090 (95% CI: 1.031–1.152) for patients admitted to hospitals in the middle tertile. Similarly, improved survival was seen across the tertiles with an adjusted inpatient mortality incidence of 35.81 (95% CI: 33.64–38.03) for hospitals with the lowest volume of severe sepsis cases and a drop to 32.07 (95% CI: 31.51–32.64) for hospitals with the highest volume.

Conclusions and Relevance

We demonstrate an association between a higher severe sepsis case volume and decreased mortality. The need for a systems-based approach for improved outcomes may require a high volume of severely septic patients.     

Nurses and Physicians in a Medical Admission Unit Can Accurately Predict Mortality of Acutely Admitted Patients: A Prospective Cohort Study

Background

There exist several risk stratification systems for predicting mortality of emergency patients. However, some are complex in clinical use and others have been developed using suboptimal methodology. The objective was to evaluate the capability of the staff at a medical admission unit (MAU) to use clinical intuition to predict in-hospital mortality of acutely admitted patients.

Methods

This is an observational prospective cohort study of adult patients (15 years or older) admitted to a MAU at a regional teaching hospital. The nursing staff and physicians predicted in-hospital mortality upon the patients'' arrival. We calculated discriminatory power as the area under the receiver-operating-characteristic curve (AUROC) and accuracy of prediction (calibration) by Hosmer-Lemeshow goodness-of-fit test.

Results

We had a total of 2,848 admissions (2,463 patients). 89 (3.1%) died while admitted. The nursing staff assessed 2,404 admissions and predicted mortality in 1,820 (63.9%). AUROC was 0.823 (95% CI: 0.762–0.884) and calibration poor. Physicians assessed 738 admissions and predicted mortality in 734 (25.8% of all admissions). AUROC was 0.761 (95% CI: 0.657–0.864) and calibration poor. AUROC and calibration increased with experience. When nursing staff and physicians were in agreement (±5%), discriminatory power was very high, 0.898 (95% CI: 0.773–1.000), and calibration almost perfect. Combining an objective risk prediction score with staff predictions added very little.

Conclusions

Using only clinical intuition, staff in a medical admission unit has a good ability to identify patients at increased risk of dying while admitted. When nursing staff and physicians agreed on their prediction, discriminatory power and calibration were excellent.     

Effectiveness of Influenza Vaccination in Patients with End-Stage Renal Disease Receiving Hemodialysis: A Population-Based Study

Background

Little is known on the effectiveness of influenza vaccine in ESRD patients. This study compared the incidence of hospitalization, morbidity, and mortality in end-stage renal disease (ESRD) patients undergoing hemodialysis (HD) between cohorts with and without influenza vaccination.

Methods

We used the insurance claims data from 1998 to 2009 in Taiwan to determine the incidence of these events within one year after influenza vaccination in the vaccine (N = 831) and the non-vaccine (N = 3187) cohorts. The vaccine cohort to the non-vaccine cohort incidence rate ratio and hazard ratio (HR) of morbidities and mortality were measured.

Results

The age-specific analysis showed that the elderly in the vaccine cohort had lower hospitalization rate (100.8 vs. 133.9 per 100 person-years), contributing to an overall HR of 0.81 (95% confidence interval (CI) 0.72–0.90). The vaccine cohort also had an adjusted HR of 0.85 [95% CI 0.75–0.96] for heart disease. The corresponding incidence of pneumonia and influenza was 22.4 versus 17.2 per 100 person-years, but with an adjusted HR of 0.80 (95% CI 0.64–1.02). The vaccine cohort had lowered risks than the non-vaccine cohort for intensive care unit (ICU) admission (adjusted HR 0.20, 95% CI 0.12–0.33) and mortality (adjusted HR 0.50, 95% CI 0.41–0.60). The time-dependent Cox model revealed an overall adjusted HR for mortality of 0.30 (95% CI 0.26–0.35) after counting vaccination for multi-years.

Conclusions

ESRD patients with HD receiving the influenza vaccination could have reduced risks of pneumonia/influenza and other morbidities, ICU stay, hospitalization and death, particularly for the elderly.     

Prognostic Value of Acute Kidney Injury after Cardiac Surgery according to Kidney Disease: Improving Global Outcomes Definition and Staging (KDIGO) Criteria

Objectives

The definition of acute renal failure has been recently reviewed, and the term acute kidney injury (AKI) was proposed to cover the entire spectrum of the syndrome, ranging from small changes in renal function markers to dialysis needs. This study was aimed to evaluate the incidence, morbidity and mortality associated with AKI (based on KDIGO criteria) in patients after cardiac surgery (coronary artery bypass grafting or cardiac valve surgery) and to determine the value of this feature as a predictor of hospital mortality (30 days).

Methods

From January 2003 to June 2013, a total of 2,804 patients underwent cardiac surgery in our service. Cox proportional hazard models were used to determine the association between the development of AKI and 30-day mortality.

Results

A total of 1,175 (42%) patients met the diagnostic criteria for AKI based on KDIGO classification during the first 7 postoperative days: 978 (35%) patients met the diagnostic criteria for stage 1 while 100 (4%) patients met the diagnostic criteria for stage 2 and 97 (3%) patients met the diagnostic criteria for stage 3. A total of 63 (2%) patients required dialysis treatment. Overall, the 30-day mortality was 7.1% (2.2%) for patients without AKI and 8.2%, 31% and 55% for patients with AKI at stages 1, 2 and 3, respectively. The KDIGO stage 3 patients who did not require dialysis had a mortality rate of 41%, while the mortality of dialysis patients was 62%. The adjusted Cox regression analysis revealed that AKI based on KDIGO criteria (stages 1–3) was an independent predictor of 30-day mortality (P<0.001 for all. Hazard ratio = 3.35, 11.94 and 24.85).

Conclusion

In the population evaluated in the present study, even slight changes in the renal function based on KDIGO criteria were considered as independent predictors of 30-day mortality after cardiac surgery.