Redefining renal dysfunction in trauma: implementation of the Acute Kidney Injury Network staging system

The incidence and associations of acute kidney injury in trauma patients admitted to critical care: A systematic review and meta-analysis

BACKGROUND

As more patients are surviving the initial effects of traumatic injury clinicians are faced with managing the systemic complications of severe tissue injury. Of these, acute kidney injury (AKI) may be a sentinel complication contributing to adverse outcomes.

OBJECTIVE

To establish the incidence of AKI in patients admitted to critical care after major trauma, to explore any risk factors and to evaluate the association of AKI with outcomes.

DATA SOURCES

Systematic search of MEDLINE, Excerpta Medica database and Cochrane library from January 2004 to April 2018.

STUDY SELECTION

Studies of adult major trauma patients admitted to critical care that applied consensus AKI criteria (risk injury failure loss end stage [RIFLE], AKI network, or kidney disease improving global outcomes) and reported clinical outcomes were assessed (PROSPERO Registration: CRD42017056781). Of the 35 full-text articles selected from the screening, 17 (48.6%) studies were included.

DATA EXTRACTION AND SYNTHESIS

We followed the PRISMA guidelines and study quality was assessed using the Newcastle-Ottawa score. The pooled incidence of AKI and relative risk of death were estimated using random-effects models.

MAIN OUTCOMES AND MEASURES

Incidence of AKI was the primary outcome. The secondary outcome was study-defined mortality.

RESULTS

We included 17 articles describing AKI outcomes in 24,267 trauma patients. The pooled incidence of AKI was 20.4% (95% confidence interval [CI], 16.5-24.9). Twelve studies reported the breakdown of stages of AKI with 55.7% of patients classified as RIFLE-R or stage 1, 30.3% as RIFLE-I or stage 2, and 14.0% as RIFLE-F or stage 3. The pooled relative risk of death with AKI compared was 3.6 (95% CI, 2.4-5.3). In addition, there was a concordant increase in odds of death among six studies that adjusted for multiple variables (adjusted odds ratio, 2.7; 95% CI, 1.9-3.8; p = <0.01).

CONCLUSION

Acute kidney injury is common after major trauma and associated with increased mortality. Future research is warranted to reduce the potential for harm associated with this subtype of AKI.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, level III.

Incidence of, Risk Factors for, and Mortality Associated With Severe Acute Kidney Injury After Gunshot Wound

IMPORTANCE

Acute kidney injury increases the risk of mortality in hospitalized patients. However, incidence of severe acute kidney injury (SAKI) and its association with mortality in civilians with gunshot wounds (GSWs) is not known.

OBJECTIVE

To determine the incidence of and risk factors associated with SAKI and acute kidney injury requiring dialysis (AKI-D) after GSWs and the association of SAKI and AKI-D with mortality among civilians in the United States.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cross-sectional study included civilians with GSW reported to the National Trauma Data Bank between July 1, 2010, and June 30, 2015. Torso GSWs were included in study; GSWs to the head were excluded. The data were analyzed between September and November 2018.

EXPOSURE

Civilians with GSW.

MAIN OUTCOMES AND MEASURES

Incidence of SAKI and AKI-D; association of SAKI and AKI-D with mortality.

RESULTS

Most of the 64 059 civilian GSWs affected men (57 431 [89.7%]) and racial/ethnic minorities (36 205 [56.5%] African American individuals; 9681 [15.1%] Hispanic individuals). Incidence of SAKI was 2.3% (1450 of 64 059), and incidence of AKI-D was 0.9% (588 of 64 059). On multivariate analysis, SAKI was associated with older age (odds ratio [OR], 1.02; 95% CI, 1.01-1.02; P < .001), male sex (OR, 1.37; 95% CI, 1.12-1.66; P = .002), diabetes (OR, 1.55; 95% CI, 1.20-2.00; P = .001), hypertension (OR, 1.76; 95% CI, 1.46-2.11; P < .001), Glasgow Coma Scale score (OR, 0.98; 95% CI, 0.96-0.99; P = .002), sepsis (OR, 13.83; 95% CI, 11.77-16.24; P < .001), hollow viscus injury (OR, 2.31; 95% CI, 2.05-2.59; P < .001), and injury severity score (OR, 1.02; 95% CI, 1.01-1.02; P < .001); AKI-D was associated with systolic blood pressure (OR, 0.99; 95% CI, 0.99-1.00; P < .001), sepsis (OR, 1.56; 95% CI, 1.18-2.04; P = .001), and injury severity score (OR, 1.01; 95% CI, 1.01-1.02; P = .001). Mortality was significantly higher in patients with AKI-D (167 of 588 patients [28.4%]) compared with patients with SAKI (172 of 862 [20.0%]) and no SAKI or AKI-D (5521 of 62 609 [8.8%]) (P < .001). Mortality was associated with older age (OR, 1.01; 95% CI, 1.01-1.01; P < .001), systolic blood pressure (OR, 0.997; 95% CI, 0.997-0.998; P < .001), Glasgow Coma Scale score (OR, 0.87; 95% CI, 0.87-0.88; P < .001), SAKI (OR, 2.32; 95% CI, 1.93-2.79; P < .001), AKI-D (OR, 1.46; 95% CI, 1.12-1.90; P < .001), hollow viscus injury (OR, 1.87; 95% CI, 1.76-1.98; P < .001), and higher injury severity score (OR, 1.01; 95% CI, 1.01-1.01; P < .001). After matching for variables except SAKI or AKI-D, patients with SAKI were twice as likely to die than patients without SAKI (320 of 1391 [23.0%] vs 158 of 1391 [11.4%]; P < .001).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, SAKI among civilians who experienced GSWs was associated with mortality.

Acute kidney injury in trauma patients admitted to the ICU: a systematic review and meta-analysis

PURPOSE

To perform a systematic review and meta-analysis of acute kidney injury (AKI) in trauma patients admitted to the intensive care unit (ICU).

METHODS

We conducted a systematic literature search of studies on AKI according to RIFLE, AKIN, or KDIGO criteria in trauma patients admitted to the ICU (PROSPERO CRD42017060420). We searched PubMed, Cochrane Database of Systematic Reviews, UpToDate, and NICE through 3 December 2018. Data were collected on incidence of AKI, risk factors, renal replacement therapy (RRT), renal recovery, length of stay (LOS), and mortality. Pooled analyses with random effects models yielded mean differences, OR, and RR, with 95% CI.

RESULTS

Twenty-four observational studies comprising 25,182 patients were included. Study quality (Newcastle-Ottawa scale) was moderate. Study heterogeneity was substantial. Incidence of post-traumatic AKI in the ICU was 24% (20-29), of which 13% (10-16) mild, 5% (3-7) moderate, and 4% (3-6) severe AKI. Risk factors for AKI were African American descent, high age, chronic hypertension, diabetes mellitus, high Injury Severity Score, abdominal injury, shock, low Glasgow Coma Scale (GCS) score, high APACHE II score, and sepsis. AKI patients had 6.0 (4.0-7.9) days longer ICU LOS and increased risk of death [RR 3.4 (2.1-5.7)] compared to non-AKI patients. In patients with AKI, RRT was used in 10% (6-15). Renal recovery occurred in 96% (78-100) of patients.

CONCLUSIONS

AKI occurred in 24% of trauma patients admitted to the ICU, with an RRT use among these of 10%. Presence of AKI was associated with increased LOS and mortality, but renal recovery in AKI survivors was good.

Acute Kidney Injury in Trauma Patients Admitted to Critical Care: Development and Validation of a Diagnostic Prediction Model

Acute Kidney Injury (AKI) complicating major trauma is associated with increased mortality and morbidity. Traumatic AKI has specific risk factors and predictable time-course facilitating diagnostic modelling. In a single centre, retrospective observational study we developed risk prediction models for AKI after trauma based on data around intensive care admission. Models predicting AKI were developed using data from 830 patients, using data reduction followed by logistic regression, and were independently validated in a further 564 patients. AKI occurred in 163/830 (19.6%) with 42 (5.1%) receiving renal replacement therapy (RRT). First serum creatinine and phosphate, units of blood transfused in first 24 h, age and Charlson score discriminated need for RRT and AKI early after trauma. For RRT c-statistics were good to excellent: development: 0.92 (0.88–0.96), validation: 0.91 (0.86–0.97). Modelling AKI stage 2–3, c-statistics were also good, development: 0.81 (0.75–0.88) and validation: 0.83 (0.74–0.92). The model predicting AKI stage 1–3 performed moderately, development: c-statistic 0.77 (0.72–0.81), validation: 0.70 (0.64–0.77). Despite good discrimination of need for RRT, positive predictive values (PPV) at the optimal cut-off were only 23.0% (13.7–42.7) in development. However, PPV for the alternative endpoint of RRT and/or death improved to 41.2% (34.8–48.1) highlighting death as a clinically relevant endpoint to RRT.

Urine flow rate monitoring in hypovolemic multiple trauma patients

Background

The urine output is an important clinical parameter of renal function and blood volume status, especially in critically ill multiple trauma patients. In the present study, the minute-to-minute urine flow rate and its variability were analyzed in hypotensive multiple trauma patients during the first 6 h of their ICU (intensive care unit) stay. These parameters have not been previously reported.

Methods

The study was retrospective and observational. Demographic and clinical data were extracted from the computerized Register Information Systems. A total of 59 patients were included in the study. The patients were divided into two study groups. Group 1 consisted of 29 multiple trauma patients whose systolic blood pressure was greater than 90 mmHg on admission to the ICU and who were consequently deemed to be hemodynamically compromised. Group 2 consisted of 30 patients whose systolic blood pressure was less than 90 mmHg on admission to the ICU and who were therefore regarded as hemodynamically uncompromised.

Results

The urine output and urine flow rate variability during the first 6 h of the patients’ ICU stay was significantly lower in group 2 than in group 1 (p < 0.001 and 0.006 respectively). Statistical analysis by the Pearson method demonstrated a strong direct correlation between decreased urine flow rate variability and decreased urine output per hour (R = 0.17; P = 0.009), decreased mean arterial blood pressure (R = 0.24; p = 0.001), and increased heart rate (R = 0.205; p = 0.001).

Conclusion

These findings suggest that minute-to-minute urine flow rate variability is a reliable incipient marker of hypovolemia and that it should therefore take its place among the parameters used to monitor the hemodynamic status of critically ill multiple trauma patients.

Risk factors for contrast-induced nephropathy and their association with mortality in patients with blunt splenic injuries

BACKGROUND

Although angioembolization increases the success rate of non-operative management in patients with blunt splenic injuries (BSI), the issue of contrast-induced nephropathy (CIN) due to serial administration of contrast medium remains unclear. We aimed to examine the risk factors of CIN and their clinical effect on mortality in patients with BSI.

METHOD

We retrospectively studied the complete data on 377 trauma patients with BSI who survived more than 48 h between July 2003 and June 2015. CIN was defined as the relative (≥25%) or absolute (≥0.5 mg/dL) increase in serum creatinine within 48 h after contrast administration. A multivariate logistic regression analysis was conducted to identify the independent predictors of CIN and mortality.

RESULTS

CIN was independently associated with body mass index (BMI) ≥ 30 kg/m² (odds ratio [OR]: 3.25, 95% confidence interval [CI]: 1.20-8.76), injury severity score (ISS) ≥ 25 (OR: 6.08, 95% CI: 2.76-13.53), and 24-h hemoglobin (Hb) < 10 g/dL (OR: 3.16, 95% CI: 1.46-6.81). CIN (OR: 19.04, 95% CI: 6.15-58.94) and diabetes (OR: 3.43, 95% CI: 1.04-11.26) were also identified as independent predictors for mortality.

CONCLUSION

In this study, we found that BMI ≥ 30 kg/m², ISS ≥ 25, and 24-h Hb < 10 g/dL were independent risk factors for the occurrence of CIN in patients with BSI. However, angioembolization was not identified to be an independent risk factor for CIN. In addition, CIN and diabetes mellitus were identified as independent risk factors for mortality in patients with BSI.

Acute kidney injury following severe trauma: Risk factors and long-term outcome

BACKGROUND

The trauma patient sustains numerous potentially harmful insults that may contribute to a notable risk of acute kidney injury (AKI). The aim of this study was to investigate the incidence of and to identify risk factors for AKI in severely injured trauma patients admitted to the intensive care unit (ICU). The patients were followed up for 1 year with respect to survival and end-stage renal disease.

METHODS

Trauma patients admitted to the ICU for more than 24 hours at a Level I trauma center were included. The outcome measure was AKI diagnosed Days 2 to 7 of ICU treatment. Regression analysis was performed to identify factors associated with AKI development.

RESULTS

A quarter of the patients (103 of 413) developed AKI within the first week of ICU admission. AKI was associated with increased 30-day (17.5% vs. 5.8%) and 1-year (26.2% vs. 7.1%) mortality. Risk factors for AKI were male sex, age, nondiabetic comorbidity, diabetes mellitus, Injury Severity Score (ISS) greater than 40, massive transfusion, and volume loading with hydroxyethyl starch (HES) within the first 24 hours. Unexpectedly, sepsis before AKI onset, admission hypotension, and extensive contrast loading (>150 mL) were not associated with AKI development. None of the surviving AKI patients had developed end-stage renal disease 1 year after injury.

CONCLUSION

AKI in ICU-admitted trauma patients is a common complication with substantial mortality. Diabetes, male sex, and severe injury were strong risk factors, but age, nondiabetic comorbidity, massive transfusion, and resuscitation with HES were also associated with postinjury AKI. Based on the results of the current study, volume resuscitation with HES cannot be recommended in trauma patients.

LEVEL OF EVIDENCE

Prognostic study, level III; therapeutic study, level IV.

Cystatin C is a moderate predictor of acute kidney injury in the early stage of traumatic hemorrhagic shock

Patients with traumatic hemorrhagic shock are highly susceptible to the development of acute kidney injury (AKI), but little data are available regarding the changes in cystatin C (CysC) in patients with traumatic hemorrhagic shock. The aim of the present study, therefore, was to investigate whether CysC has a higher value than serum creatinine (SCr) and urea for use in monitoring glomerular function in traumatic hemorrhagic shock. Data from a cohort of patients with traumatic hemorrhagic shock, who had been admitted to a trauma center, were collected. Receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic value of serum CysC, SCr and urea for the identification of renal dysfunction, and the data were expressed as the area under the curve (AUC). CysC was not significantly affected by gender, age, mechanism of injury or time between injury and arrival at the center in the patients with traumatic hemorrhagic shock. The CysC level of the patients was significantly higher than that of the normal subjects (1.10±0.36 vs. 0.91±0.34 mg/l); the SCr and urea levels of the patients were also significantly increased compared with those of the normal subjects. Nonparametric ROC plots of the sensitivity and specificity of SCr, CysC and urea for the detection of AKI revealed AUC values of 0.901 [95% confidence interval (CI), 0.791-1.000], 0.728 (95% CI, 0.570-0.886) and 0.709 (95% CI, 0.552-0.865) for SCr, CysC and urea, respectively. No significant correlation between mortality and CysC, SCr or urea was found. These data indicate that the level of CysC is significantly increased in the early stage of traumatic hemorrhagic shock and that CysC can be used as a marker to predict AKI; however, the diagnostic utility of CysC remains lower than that of SCr in the early stage of the condition.

Critical Care for the Patient With Multiple Trauma

Trauma remains the leading cause of death worldwide and the leading cause of death in those less than 44 years old in the United States. Admission to a verified trauma center has been shown to decrease mortality following a major injury. This decrease in mortality has been a direct result of improvements in the initial evaluation and resuscitation from injury as well as continued advances in critical care. As such, it is vital that intensive care practitioners be familiar with various types of injuries and their associated treatment strategies as well as their potential complications in order to minimize the morbidity and mortality frequently seen in this patient population.

Effect of renal angioembolization on post-traumatic acute kidney injury after high-grade renal trauma: a comparative study of 52 consecutive cases

BACKGROUND

Acute kidney injury (AKI) is associated with unfavourable outcomes and higher mortality after trauma. Renal angioembolization (RAE) has proved efficiency in the management of high-grade renal trauma (HGRT), but inevitably expose to unavoidable ischaemic areas or contrast medium nephrotoxicity which may impair renal function in the following hours. The aim of this study was to assess the potential acute impact of RAE on renal function in a consecutive series of HGRTs treated nonoperatively.

MATERIALS AND METHODS

Of 101 cases of renal trauma admitted to our Regional Trauma Center between January 2005 and January 2010, 52 cases of HGRT were treated nonoperatively; they were retrospectively classified into 2 groups according to whether RAE was used. Incidence and progression of AKI (RIFLE classification), maximum increase in serum creatinine (SCr), level since admission and recovery of renal function at discharge were compared between the groups. Multivariable analysis was performed to determine the role of RAE as an independent risk factor of AKI.

RESULTS

RAE was performed in 10 patients within the first 48h. The RAE and no RAE groups were comparable in terms of severity score, renal injury grade, and level of SCr on admission. AKI incidence (RIFLE score Risk or worse) after 48 and 96h was 33% and 10%, respectively and did not differ significantly between groups at 48h (p=1.00) or 96h (p=1.00). The median maximum increase in SCr was significantly higher in no RAE than RAE group (30.4% vs. 6.9%, p=0.04). RAE was not found to be a significant variable in a multiple linear regression analysis predicting maximum SCr rise (p=0.34). SCr at discharge was >120% of baseline in only 5 patients, with no difference according to RAE (p=0.24).

CONCLUSION

In a population of nonoperatively treated HGRT, the incidence of AKI decreased from almost 30% to 10% at 48h and 96h. RAE proceeding did not seem to affect significantly the occurrence and course of AKI or renal recovery. The decision to use RAE should probably not be restricted by fear of worsening renal function.

Acute kidney injury is surprisingly common and a powerful predictor of mortality in surgical sepsis

BACKGROUND

Acute kidney injury (AKI) is a common and often catastrophic complication in hospitalized patients; however, the impact of AKI in surgical sepsis remains unknown. We used Risk, Injury, Failure, Loss, End stage (RIFLE) consensus criteria to define the incidence of AKI in surgical sepsis and characterize the impact of AKI on patient morbidity and mortality.

METHODS

Our prospective, institutional review board-approved sepsis research database was retrospectively queried for the incidence of AKI by RIFLE criteria, excluding those with chronic kidney disease. Patients were grouped into sepsis, severe sepsis, and septic shock by refined consensus criteria. Data including demographics, baseline biomarkers of organ dysfunction, and outcomes were compared by Student's t test and χ test. Multivariable regression analysis was performed for the effect of AKI on mortality adjusting for age, sex, African-American race, elective surgery, Acute Physiology and Chronic Health Evaluation II score, septic shock versus severe sepsis, and sepsis source.

RESULTS

During the 36-month study period ending on December 2010, 246 patients treated for surgical sepsis were evaluated. AKI occurred in 67% of all patients, and 59%, 60%, and 88% of patients had sepsis, surgical sepsis, and septic shock, respectively. AKI was associated with Hispanic ethnicity, several baseline biomarkers of organ dysfunction, and a greater severity of illness. Patients with AKI had fewer ventilator-free and intensive care unit-free days and a decreased likelihood of discharge to home. Morbidity and mortality increased with severity of AKI, and AKI of any severity was found to be a strong predictor of hospital mortality (odds ratio, 10.59; 95% confidence interval, 1.28-87.35; p = 0.03) in surgical sepsis.

CONCLUSION

AKI frequently complicates surgical sepsis, and serves as a powerful predictor of hospital mortality in severe sepsis and septic shock.

LEVEL OF EVIDENCE

Prognostic and epidemiologic study, level III.

Epidemiology of acute kidney injury in the intensive care unit

The incidence of acute kidney injury (AKI) in the intensive care unit (ICU) has increased during the past decade due to increased acuity as well as increased recognition. Early epidemiology studies were confounded by erratic definitions of AKI until recent consensus guidelines (RIFLE and AKIN) standardized its definition. This paper discusses the incidence of AKI in the ICU with focuses on specific patient populations. The overall incidence of AKI in ICU patients ranges from 20% to 50% with lower incidence seen in elective surgical patients and higher incidence in sepsis patients. The incidence of contrast-induced AKI is less (11.5%–19% of all admissions) than seen in the ICU population at large. AKI represents a significant risk factor for mortality and can be associated with mortality greater than 50%.

Are surrogate assumptions and use of diuretics associated with diagnosis and staging of acute kidney injury after cardiac surgery?

BACKGROUND AND OBJECTIVES

This study measured the association between the Acute Kidney Injury Network (AKIN) diagnostic and staging criteria and surrogates for baseline serum creatinine (SCr) and body weight, compared urine output (UO) with SCr criteria, and assessed the relationships between use of diuretics and calibration between criteria and prediction of outcomes.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a retrospective cohort study using prospective measurements of SCr, hourly UO, body weight, and drug administration records from 5701 patients admitted, after cardiac surgery, to a cardiac intensive care unit between 1995 and 2006.

RESULTS

More patients (n=2424, 42.5%) met SCr diagnostic criteria with calculated SCr assuming a baseline estimated GFR of 75 ml/min per 1.73 m(2) than with known baseline SCr (n=1043, 18.3%). Fewer patients (n=484, 8.5%) met UO diagnostic criteria with assumed body weight (70 kg) than with known weight (n=624, 10.9%). Agreement between SCr and UO criteria was fair (κ=0.28; 95% confidence interval 0.25-0.31). UO diagnostic criteria were specific (0.95; 0.94-0.95) but insensitive (0.36; 0.33-0.39) compared with SCr. Intravenous diuretics were associated with higher probability of falling below the UO diagnostic threshold compared with SCr, higher 30-day mortality (relative risk, 2.27; 1.08-4.76), and the need for renal support (4.35; 1.82-10.4) compared with no diuretics.

CONCLUSIONS

Common surrogates for baseline estimated GFR and body weight were associated with misclassification of AKIN stage. UO criteria were insensitive compared with SCr. Intravenous diuretic use further reduced agreement and confounded association between AKIN stage and 30-day mortality or need for renal support.

Acute kidney injury in patients with severe traumatic brain injury: implementation of the acute kidney injury network stage system

BACKGROUND

There is limited information on the incidence and effect of acute kidney injury (AKI) in patients with severe traumatic brain injury (TBI), although AKI may affect outcome. Recently, acute kidney injury network (AKIN) classification has been widely accepted as a consensus definition for AKI. The aim of this study is to estimate the frequency and level of severity of AKI in patients with severe TBI by using AKIN criteria and to study whether AKI affects outcome.

METHODS

The authors retrospectively identified a total of 136 patients with severe TBI admitted to the neurosurgical center during a 3-year period ending May 2010. Demographic data, severity of TBI, serum creatinine, urine output, outcome at 6 month, and death were collected. Renal function was assessed by using AKIN criteria.

RESULTS

Thirty-one patients (23%) were classified as having AKI by using AKIN criteria during their hospitalization. Of them, 21 patients (68%) were stratified as stage 1, 7 patients (22%) as stage 2, and 3 patients (10%) as stage 3. Patients who developed AKI were older, had lower Glasgow coma scale at admission, and had higher level of admission serum creatinine and blood urea nitrogen. Patients with AKI had higher mortality and worse outcome when compared with patients with normal renal function. Furthermore, patients with mild renal dysfunction (stage 1 AKI) are also found having increased mortality and worse long-term outcome, compared with patients without renal dysfunction.

CONCLUSION

It is demonstrated using the newly defined AKIN criteria for renal dysfunction that AKI is a relatively common feature in patients with severe TBI, and even seemingly insignificant decrease in renal function may be associated with worse outcome. This study highlights the importance of close surveillance of renal function and stresses the value of renal hygiene in the severe TBI population.

[Clinical approach to renal trauma]

Management of kidney injuries is an uncommon challenge to urologists. Therapy has evolved in recent years from mainly surgical to predominantly conservative treatment. Immediate surgical intervention for renal trauma is now only necessary in rare instances. This overview is based on the guidelines of the European Association of Urology and the Societé International d'Urologie as well as clinical experience and is intended to provide practical advice for treatment of renal trauma.

Fenoldopam use in a burn intensive care unit: a retrospective study

BACKGROUND

Fenoldopam mesylate is a highly selective dopamine-1 receptor agonist approved for the treatment of hypertensive emergencies that may have a role at low doses in preserving renal function in those at high risk for or with acute kidney injury (AKI). There is no data on low-dose fenoldopam in the burn population. The purpose of our study was to describe our use of low-dose fenoldopam (0.03-0.09 mug/kg/min) infusion in critically ill burn patients with AKI.

METHODS

We performed a retrospective analysis of consecutive patients admitted to our burn intensive care unit (BICU) with severe burns from November 2005 through September 2008 who received low-dose fenoldopam. Data obtained included systolic blood pressure, serum creatinine, vasoactive medication use, urine output, and intravenous fluid. Patients on concomitant continuous renal replacement therapy were excluded. Modified inotrope score and vasopressor dependency index were calculated. One-way analysis of variance with repeated measures, Wilcoxson signed rank, and chi-square tests were used. Differences were deemed significant at p < 0.05.

RESULTS

Seventy-seven patients were treated with low-dose fenoldopam out of 758 BICU admissions (10%). Twenty (26%) were AKI network (AKIN) stage 1, 14 (18%) were AKIN stage 2, 42 (55%) were AKIN stage 3, and 1 (1%) was AKIN stage 0. Serum creatinine improved over the first 24 hours and continued to improve through 48 hours (p < 0.05). There was an increase in systolic blood pressure in the first 24 hours that was sustained through 48 hours after initiation of fenoldopam (p < 0.05). Urine output increased after initiation of fenoldopam without an increase in intravenous fluid requirement (p < 0.05; p = NS). Modified inotrope score and vasopressor dependency index both decreased over 48 hours (p < 0.0001; p = 0.0012).

CONCLUSIONS

These findings suggest that renal function was preserved and that urine output improved without a decrease in systolic blood pressure, increase in vasoactive medication use, or an increase in resuscitation requirement in patients treated with low-dose fenoldopam. A randomized controlled trial is required to establish the efficacy of low-dose fenoldopam in critically ill burn patients with AKI.