Renin Levels and Angiotensin II Responsiveness in Vasopressor-Dependent Hypotension.

OBJECTIVES: The relationship between renin levels, exposure to renin-angiotensin system (RAS) inhibitors, angiotensin II (ANGII) responsiveness, and outcome in patients with vasopressor-dependent vasodilatory hypotension is unknown. DESIGN: We conducted a single-center prospective observational study to explore whether recent RAS inhibitor exposure affected baseline renin levels, whether baseline renin levels predicted ANGII responsiveness, and whether renin levels at 24 hours were associated with clinical outcomes. SETTING: An academic ICU in Melbourne, VIC, Australia. PATIENTS: Forty critically ill adults who received ANGII as the primary agent for vasopressor-dependent vasodilatory hypotension who were included in the Acute Renal effects of Angiotensin II Management in Shock study. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: After multivariable adjustment, recent exposure to a RAS inhibitor was independently associated with a relative increase in baseline renin levels by 198% (95% CI, 36-552%). The peak amount of ANGII required to achieve target mean arterial pressure was independently associated with baseline renin level (increase by 46% per ten-fold increase; 95% CI, 8-98%). Higher renin levels at 24 hours after ANGII initiation were independently associated with fewer days alive and free of continuous renal replacement therapy (CRRT) (-7 d per ten-fold increase; 95% CI, -12 to -1). CONCLUSIONS: In patients with vasopressor-dependent vasodilatory hypotension, recent RAS inhibitor exposure was associated with higher baseline renin levels. Such higher renin levels were then associated with decreased ANGII responsiveness. Higher renin levels at 24 hours despite ANGII infusion were associated with fewer days alive and CRRT-free. These preliminary findings emphasize the importance of the RAS and the role of renin as a biomarker in patients with vasopressor-dependent vasodilatory hypotension.

Characteristics and Outcomes of Children and Young Adults With Sepsis Requiring Continuous Renal Replacement Therapy: A Comparative Analysis From the Worldwide Exploration of Renal Replacement Outcomes Collaborative in Kidney Disease (WE-ROCK).

OBJECTIVES: Pediatric sepsis-associated acute kidney injury (AKI) often requires continuous renal replacement therapy (CRRT), but limited data exist regarding patient characteristics and outcomes. We aimed to describe these features, including the impact of possible dialytrauma (i.e., vasoactive requirement, negative fluid balance) on outcomes, and contrast them to nonseptic patients in an international cohort of children and young adults receiving CRRT. DESIGN: A secondary analysis of Worldwide Exploration of Renal Replacement Outcomes Collaborative in Kidney Disease (WE-ROCK), an international, multicenter, retrospective study. SETTING: Neonatal, cardiac and PICUs at 34 centers in nine countries from January 1, 2015, to December 31, 2021. PATIENTS: Patients 0-25 years old requiring CRRT for AKI and/or fluid overload. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 1016 patients, 446 (44%) had sepsis at CRRT initiation and 650 (64%) experienced Major Adverse Kidney Events at 90 days (MAKE-90) (defined as a composite of death, renal replacement therapy [RRT] dependence, or > 25% decline in estimated glomerular filtration rate from baseline at 90 d from CRRT initiation). Septic patients were less likely to liberate from CRRT by 28 days (30% vs. 38%; p < 0.001) and had higher rates of MAKE-90 (70% vs. 61%; p = 0.002) and higher mortality (47% vs. 31%; p < 0.001) than nonseptic patients; however, septic survivors were less likely to be RRT dependent at 90 days (10% vs. 18%; p = 0.011). On multivariable regression, pre-CRRT vasoactive requirement, time to negative fluid balance, and median daily fluid balance over the first week of CRRT were not associated with MAKE-90; however, increasing duration of vasoactive requirement was independently associated with increased odds of MAKE-90 (adjusted OR [aOR], 1.16; 95% CI, 1.05-1.28) and mortality (aOR, 1.20; 95% CI, 1.1-1.32) for each additional day of support. CONCLUSIONS: Septic children requiring CRRT have different clinical characteristics and outcomes compared with those without sepsis, including higher rates of mortality and MAKE-90. Increasing duration of vasoactive support during the first week of CRRT, a surrogate of potential dialytrauma, appears to be associated with these outcomes.

Global structures, practices, and tools for provision of hemodialysis.

BACKGROUND: Hemodialysis (HD) is the most commonly utilized modality for kidney replacement therapy worldwide. This study assesses the organizational structures, availability, accessibility, affordability and quality of HD care worldwide. METHODS: This cross-sectional study relied on desk research data as well as survey data from stakeholders (clinicians, policymakers and patient advocates) from countries affiliated with the International Society of Nephrology from July to September 2022. RESULTS: Overall, 167 countries or jurisdictions participated in the survey. In-center HD was available in 98% of countries with a median global prevalence of 322.7 [interquartile range (IQR) 76.3-648.8] per million population (pmp), ranging from 12.2 (IQR 3.9-103.0) pmp in Africa to 1575 (IQR 282.2-2106.8) pmp in North and East Asia. Overall, home HD was available in 30% of countries, mostly in countries of Western Europe (82%). In 74% of countries, more than half of people with kidney failure were able to access HD. HD centers increased with increasing country income levels from 0.31 pmp in low-income countries to 9.31 pmp in high-income countries. Overall, the annual cost of in-center HD was US$19 380.3 (IQR 11 817.6-38 005.4), and was highest in North America and the Caribbean (US$39 825.9) and lowest in South Asia (US$4310.2). In 19% of countries, HD services could not be accessed by children. CONCLUSIONS: This study shows significant variations that have remained consistent over the years in availability, access and affordability of HD across countries with severe limitations in lower-resourced countries.

Hemoadsorption: Consensus report of the 30th Acute Disease Quality Initiative workgroup.

Adsorption-based extracorporeal therapies have been subject to technical developments and clinical application for close to five decades. More recently, new technological developments in membrane and sorbent manipulation have made it possible to deliver more biocompatible extracorporeal adsorption therapies to patients with a variety of conditions. There are several key rationales based on physicochemical principles and clinical considerations that justify the application and investigation of such therapies as evidenced by multiple ex-vivo, experimental, and clinical observations. Accordingly, unspecific adsorptive extracorporeal therapies have now been applied to the treatment of a wide array of conditions from poisoning to drug overdoses, to inflammatory states and sepsis, and acute or chronic liver and kidney failure. In response to the rapidly expanding knowledge base and increased clinical evidence, we convened an Acute Disease Quality Initiative (ADQI) consensus conference dedicated to such treatment. The data show that hemoadsorption has clinically acceptable short-term biocompatibility and safety, technical feasibility, and experimental demonstration of specified target molecule removal. Pilot studies demonstrate potentially beneficial effects on physiology and larger studies of endotoxin-based hemoadsorption have identified possible target phenotypes for larger randomized controlled trials (RCTs). Moreover, in a variety of endogenous and exogenous intoxications, removal of target molecules has been confirmed in vivo. However, some studies have raised concerns about harm or failed to deliver benefits. Thus, despite many achievements, modern hemoadsorption remains a novel and experimental intervention with limited data, and a large research agenda.

Cardiac Output Changes during Renal Replacement Therapy: A Scoping Review.

INTRODUCTION: Renal replacement therapy (RRT) is associated with hypotension. However, its impact on cardiac output (CO) is less understood. We aimed to describe current knowledge of CO monitoring and changes during RRT. METHODS: We searched MEDLINE, Embase, and Cochrane from January 1, 2000, to January 31, 2023, using Covidence for studies of intermittent hemodialysis (IHD) and continuous RRT (CRRT) with at least three CO measurements during treatment. Two independent reviewers screened citations, and a third resolved disagreements. The findings did not allow meta-analysis and are presented descriptively. RESULTS: We screened 3,285 articles and included 48 (37 during IHD, nine during CRRT, and two during both). Non-invasive devices (electrical conductivity techniques and finger cuff pulse contour) were the most common CO measurement techniques (21 studies). The median baseline cardiac index in IHD studies was 3 L/min/m2 (95% CI, 2.7-3.39). Among the 88 patient cohorts studied, a decrease in CO occurred in 63 (72%). In 16 cohorts, the decrease was severe (>25%). Changes in blood pressure (BP) were not concordant in extent or direction with changes in CO. The decrease in CO correlated weakly with ultrafiltration rate (r = -0.3, p = 0.05) and strongly with changes in systemic vascular resistance (SVR) (r = -0.6, p < 0.001). CONCLUSION: There are limited data on CO changes during RRT. However, a decrease in CO appeared common and was marked in 1 of 5 patient cohorts. Such decreases often occurred without BP changes and were associated with increased SVR.

Relative Blood Volume Monitoring during Continuous Renal Replacement Therapy: A Prospective Observational Study.

INTRODUCTION: Hematocrit monitoring during continuous renal replacement therapy (CRRT) allows the continuous estimation of relative blood volume (RBV). This may enable early detection of intravascular volume depletion prior to clinical sequelae. We aimed to investigate the feasibility of extended RBV monitoring and its epidemiology during usual CRRT management by clinicians unaware of RBV. Moreover, we studied the association between changes in RBV and net ultrafiltration (NUF) rates. METHODS: In a cohort of adult intensive care unit patients receiving CRRT, we continuously monitored hematocrit and RBV using a pre-filter noninvasive optical sensor. We analyzed temporal changes in RBV and investigated the association between RBV change and NUF rates, using the classification of NUF rates into low, moderate, or high based on predefined cut-offs. RESULTS: We obtained >60,000 minute-by-minute measurements in >1,000 CRRT hours in 36 patients. The median RBV change was negative (decrease) in 69% of patients and the median peak change in RBV was -9.3% (interquartile range: -3.9% to -14.3%). Moreover, the median RBV decreased from baseline by >5% in 40.2% of measurements and by >10% in 20.6% of measurements. Finally, RBV decreased significantly more when patients received a high NUF rate (>1.75 mL/kg/h) compared to low or moderate NUF rates (5.32% vs. 1.93% or 1.97%, p < 0.001). CONCLUSION: Continuous hematocrit and RBV monitoring during CRRT was feasible. RBV decreased significantly during CRRT, and decreases were greater with higher NUF rates. RBV monitoring may help optimize NUF management and prevent the occurrence of intravascular volume depletion.

A Pilot and Feasibility Study of Continuous Cardiac Output and Blood Pressure Monitoring during Intermittent Hemodialysis.

INTRODUCTION: Hypotension is common during intermittent hemodialysis (IHD) and may be due to a decreased cardiac index (CI). However, no study has simultaneously and continuously measured CI and mean arterial pressure (MAP) to understand the prevalence, severity, and duration of CI decreases or relate them to MAP, blood volume (BV), and net ultrafiltration (NUF) rate. METHODS: In a prospective, pilot and feasibility investigation, we studied 10 chronic IHD patients. We used the ClearSight System™ to continuously monitor CI and MAP; the CRIT-LINE®IV monitor to detect BV changes and collected data on NUF rate. RESULTS: Device tolerance and compliance were 100%. All patients experienced at least ≥1 episode of severe CI decrease (>25% from baseline), with a median duration of 24 min (IQR 6-87) and of 68 min [14-106] for moderate decreases (>15% but ≤25% from baseline). Eight patients experienced a low CI state (<2.2 L/min/m2). The lowest CI was 0.9 L/min/m2 with a concomitant MAP of 94 mm Hg. When the fall in CI was severe, MAP increased in 58% of cases and remained stable in 28%. Overall, CI decreased by -0.55 L/min/m2 when BV decrease was moderate versus mild (p < 0.001) and by -0.8 L/min/m2 when NUF rate was high versus low (p < 0.001). CONCLUSION: Continuous CI monitoring is feasible in IHD and shows frequent moderate-severe CI decreases, sometimes to low CI state levels. Such decreases are typically associated with markers of decreased intravascular volume status but not with a decrease in MAP, implying marked vasoconstriction.

Haematocrit monitoring and blood volume estimation during continuous renal replacement therapy.

BACKGROUND: Continuous haemoglobin, venous blood oxygen saturation, and haematocrit (Hct) monitoring is currently not applied during continuous renal replacement therapy (CRRT). Such Hct monitoring enables estimation of changes in blood volume as percentage change (ΔBV%) from therapy start time and is incorporated into intermittent haemodialysis machines but not CRRT machines despite its potential to optimise fluid management in CRRT patients. METHODS: To overcome this problem, we used a standalone monitor (CRIT-LINE®IV, Fresenius Medical Care, Concord, USA) with an associated in-line blood chamber (CRIT-LINE®IV Blood Chamber, Fresenius Medical Care, Concord, USA) and designed our own adaptor connection piece (TekMed and Morriset, Melbourne and Brisbane, Australia) to allow these readings at the vascular access outflow and recorded data for estimated Hct and derived ΔBV% during CRRT. RESULTS: We report on this technique with an illustrative case example and 12 h of CRRT data on the fluid loss rate prescribed, hourly net patient fluid loss (range: 0-308 mL/h), mean arterial pressure, norepinephrine dose (range: 5-14 mcg/min), estimated continuous Hct and ΔBV%, and the otherwise undetected diagnosis of an approximate 15 % decrease in blood volume during the CRRT. CONCLUSION: We have described a technical CRRT circuit modification that can facilitate a previously unavailable assessment of fluid shifts during CRRT. Further application in clinical trials is now possible.

Sodium Bicarbonate for Metabolic Acidosis in the ICU: Results of a Pilot Randomized Double-Blind Clinical Trial.

OBJECTIVES: To identify the best population, design of the intervention, and to assess between-group biochemical separation, in preparation for a future phase III trial. DESIGN: Investigator-initiated, parallel-group, pilot randomized double-blind trial. SETTING: Eight ICUs in Australia, New Zealand, and Japan, with participants recruited from April 2021 to August 2022. PATIENTS: Thirty patients greater than or equal to 18 years, within 48 hours of admission to the ICU, receiving a vasopressor, and with metabolic acidosis (pH < 7.30, base excess [BE] < -4 mEq/L, and Pa co2 < 45 mm Hg). INTERVENTIONS: Sodium bicarbonate or placebo (5% dextrose). MEASUREMENTS AND MAIN RESULT: The primary feasibility aim was to assess eligibility, recruitment rate, protocol compliance, and acid-base group separation. The primary clinical outcome was the number of hours alive and free of vasopressors on day 7. The recruitment rate and the enrollment-to-screening ratio were 1.9 patients per month and 0.13 patients, respectively. Time until BE correction (median difference, -45.86 [95% CI, -63.11 to -28.61] hr; p < 0.001) and pH correction (median difference, -10.69 [95% CI, -19.16 to -2.22] hr; p = 0.020) were shorter in the sodium bicarbonate group, and mean bicarbonate levels in the first 24 hours were higher (median difference, 6.50 [95% CI, 4.18 to 8.82] mmol/L; p < 0.001). Seven days after randomization, patients in the sodium bicarbonate and placebo group had a median of 132.2 (85.6-139.1) and 97.1 (69.3-132.4) hours alive and free of vasopressor, respectively (median difference, 35.07 [95% CI, -9.14 to 79.28]; p = 0.131). Recurrence of metabolic acidosis in the first 7 days of follow-up was lower in the sodium bicarbonate group (3 [20.0%] vs. 15 [100.0%]; p < 0.001). No adverse events were reported. CONCLUSIONS: The findings confirm the feasibility of a larger phase III sodium bicarbonate trial; eligibility criteria may require modification to facilitate recruitment.

Adults are just big kids: pediatric considerations for adult critical care nephrology.

PURPOSE OF REVIEW: In recent years, there has been growing attention to pediatric kidney health, especially pediatric acute kidney injury (AKI). However, there has been limited focus on the role of pediatric AKI on adult kidney health, specifically considerations for the critical care physician. RECENT FINDINGS: We summarize what is known in the field of pediatric AKI to inform adult medical care including factors throughout the early life course, including perinatal, neonatal, and pediatric exposures that impact survivor care later in adulthood. SUMMARY: The number of pediatric AKI survivors continues to increase, leading to a higher burden of chronic kidney disease and other long-term co-morbidities later in life. Adult medical providers should consider pediatric history and illnesses to inform the care they provide. Such knowledge may help internists, nephrologists, and intensivists alike to improve risk stratification, including a lower threshold for monitoring for AKI and kidney dysfunction in their patients.

Impact of Continuous Renal Replacement Therapy Initiation on Urine Output and Fluid Balance: A Multicenter Study.

INTRODUCTION: The effect of continuous renal replacement therapy (CRRT) on renal function is poorly understood. However, the initiation of CRRT may induce oliguria. We aimed to investigate the impact of CRRT commencement on urine output (UO). METHODS: This was a retrospective cohort study in two intensive care units. We included all patients who underwent CRRT and collected data on hourly UO and fluid balance before and after CRRT commencement. We performed an interrupted time series analysis using segmented regression to assess the relationship between CRRT commencement and UO. RESULTS: We studied 1,057 patients. Median age was 60.7 years (interquartile range [IQR], 48.3-70.6), and the median APACHE III was 95 (IQR, 76-115). Median time to CRRT was 17 h (IQR, 5-49). With start of CRRT, the absolute difference in mean hourly UO and mean hourly fluid balance was -27.0 mL/h (95% CI: -32.1 to -21.8; p value < 0.01) and - 129.3 mL/h (95% CI: -169.2 to -133.3), respectively. When controlling for pre-CRRT temporal trends and patient characteristics, there was a rapid post-initiation decrease in UO (-0.12 mL/kg/h; 95% CI: -0.17 to -0.08; p value < 0.01) and fluid balance (-78.1 mL/h; 95% CI: -87.9 to -68.3; p value < 0.01), which was sustained over the first 24 h of CRRT. Change in UO and fluid balance were only weakly correlated (r -0.29; 95% CI: -0.35 to -0.23; p value < 0.01). CONCLUSION: Commencement of CRRT was associated with a significant decrease in UO that could not be explained by extracorporeal fluid removal.

Community-acquired versus hospital-acquired acute kidney injury at a large Australian metropolitan quaternary referral centre: incidence, associations and outcomes.

BACKGROUND: There is increasing global incidence of acute kidney injury (AKI) and significant short- and long-term impacts on patients. AIMS: To determine incidence and outcomes of community-acquired AKI (CA-AKI) and hospital-acquired AKI (HA-AKI) among inpatients in the Australian healthcare setting using modern health information systems. METHODS: A retrospective cohort study of adult patients admitted to a quaternary hospital in Melbourne, Australia, between 1 January 2018 and 31 December 2019 utilising an electronic data warehouse. Participants included adult patients admitted for >24 h who had more than one serum creatinine level recorded during admission. Kidney transplant and maintenance dialysis patients were excluded. Main outcomes measured included AKI, as classified by the Kidney Disease Improving Global Outcomes (KDIGO) criteria, hospital length of stay and 30-day mortality. RESULTS: A total of 6477 AKI episodes was identified across 43 791 admissions. Of all AKI episodes, 77% (n = 5011), 15% (n = 947) and 8% (n = 519) were KDIGO stage 1, 2 and 3 respectively. HA-AKI accounted for 55.9% episodes. Patients required intensive care unit admission in 22.7% (n = 1100) of CA-AKI and 19.3% (n = 935) of HA-AKI, compared with 7.5% (n = 2815) of patients with no AKI (P = 0.001). Patients with AKI were older with more co-morbidities, particularly chronic kidney disease (CKD). Length of stay was longer in CA-AKI (8.8 days) and HA-AKI (11.8 days) compared with admissions without AKI (4.9 days; P < 0.001). Thirty-day mortality was increased with CA-AKI (10.2%) and HA-AKI (12.8%) compared with no AKI (3.7%; P < 0.001). CONCLUSION: The incidence of AKI detected by the electronic data warehouse was higher than previously reported. Patients who experienced AKI had greater morbidity and mortality. CKD was an important risk factor for AKI in hospitalised patients.

Estimating baseline creatinine to detect acute kidney injury in patients with chronic kidney disease.

BACKGROUND: Accurately estimating baseline kidney function is essential for diagnosing acute kidney injury (AKI) in patients with chronic kidney disease (CKD). We developed and evaluated novel equations to estimate baseline creatinine in patients with AKI on CKD. METHODS: We retrospectively analysed 5649 adults with AKI out of 11 254 CKD patients, dividing them evenly into derivation and validation groups. Using quantiles regression, we created equations to estimate baseline creatinine, considering historical creatinine values, months since measurement, age, and sex from the derivation dataset. We assessed performance against back-estimation equations and unadjusted historical creatinine values using the validation dataset. RESULTS: The optimal equation adjusted the most recent creatinine value for time since measurement and sex. Estimates closely matched the actual baseline at AKI onset, with median (95% confidence interval) differences of just 0.9% (-0.8% to 2.1%) and 0.6% (-1.6% to 3.9%) when the most recent value was within 6 months to 30 days and 2 years to 6 months before AKI onset, respectively. The equation improved AKI event reclassification by an additional 2.5% (2.0% to 3.0%) compared to the unadjusted most recent creatinine value and 7.3% (6.2% to 8.4%) compared to the CKD-EPI 2021 back-estimation equation. CONCLUSION: Creatinine levels drift in patients with CKD, causing false positives in AKI detection without adjustment. Our novel equation adjusts the most recent creatinine value for drift over time. It provides more accurate baseline creatinine estimation in patients with suspected AKI on CKD, which reduces false-positive AKI detection, improving patient care and management.

Impact of haemodialysis hours on outcomes in older patients.

AIM: Previous studies report an association between longer haemodialysis treatment sessions and improved survival. Worldwide, there is a trend to increasing age among prevalent patients receiving haemodialysis. This analysis aimed to determine whether the mortality benefit of longer haemodialysis treatment sessions diminishes with increasing age. METHODS: This was a retrospective cohort study of people who first commenced thrice-weekly haemodialysis aged ≥65 years, reported to the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry from 2005 to 2015, included from 90 days after dialysis start. The primary outcome was all-cause mortality. Cox regression analysis was performed with haemodialysis session duration the exposure of interest. RESULTS: Of 8224 people who commenced haemodialysis as their first treatment for kidney failure aged ≥65 years during this period, 4727 patients died. Longer dialysis hours per session was associated with a decreased risk of death in unadjusted analyses [hazard ratio, HR, for ≥5 h versus 4 to <4.5 h: 0.81 (0.75-0.88, p < .001)]. Patients having longer dialysis sessions were younger but had greater co-morbidity. In an adjusted model including age and other variables, the survival benefit of longer hours was only partially attenuated [HR for previous comparison: 0.75 (0.69-0.82, p < .001)], and no interaction between age and hours was demonstrated (p = .89). CONCLUSION: The apparent survival benefit associated with longer haemodialysis session length appears to be preserved in patients 65 years or older. In practice, the benefit of longer dialysis hours should be carefully weighed against other factors in this patient group.

The epidemiology of rapid response team activation amongst patients undergoing major gastrointestinal surgery.

BACKGROUND: Clinical deterioration requiring rapid response team (RRT) review is associated with increased morbidity amongst hospitalised patients. The frequency of and association with RRT calls in patients undergoing major gastrointestinal surgery is unknown. Understanding the epidemiology of RRT calls might identify areas for quality improvement in this cohort. OBJECTIVES: The objective of this study is to identify perioperative risks and outcome associations with RRT review following major gastrointestinal surgery. METHODS: We conducted a retrospective cohort study using electronic databases at a large Australian university hospital. We included adult patients admitted for major gastrointestinal surgery between 1 January 2015 and 31 March 2018. RESULTS: Of 7158 patients, 514 (7.4%) required RRT activation postoperatively. After adjustment, variables associated with RRT activation included the following: hemiplegia/paraplegia (odds ratio [OR]: 8.0, 95% confidence interval [CI]: 2.3 to 27.8, p = 0.001), heart failure (OR: 6.9, 95% CI: 3.3 to 14.6, p < 0.001), peripheral vascular disease (OR: 5.3, 95% CI: 2.7 to 10.4, p < 0.001), peptic ulcer disease (OR: 4.2, 95% CI: 2.2 to 8.0, p < 0.001), chronic obstructive pulmonary disease (OR: 4.0, 95% CI: 2.2 to 7.2, p < 0.001), and emergency admission status (OR: 2.6, 95% CI: 2.1 to 3.3, p < 0.001). Following the index operation, 46% of first RRT activations occurred within 24 h of surgery and 61% had occurred within 48 h. The most common triggers for RRT activation were tachycardia, hypotension, and tachypnoea. Postoperative RRT activation was associated with in-hospital mortality (OR: 6.7, 95% CI: 3.8 to 11.8, p < 0.001), critical care admission (incidence rate ratio: 8.18, 95% CI: 5.23 to 12.77, p < 0.001), and longer median length of hospital stay (12 days vs. 2 days, p < 0.001) compared to no RRT activation. CONCLUSION: After major gastrointestinal surgery, one in 14 patients had an RRT activation, almost half within 24 h of surgery. Such activation was independently associated with increased morbidity and mortality. Identified associations may guide more pre-emptive management for those at an increased risk of RRT activation.

Features, risk factors, and outcomes of older internal medicine patients triggering a medical emergency team call.

BACKGROUND: Information about the epidemiology of older Internal Medicine patients receiving medical emergency team (MET) calls is limited. We assessed the prevalence, characteristics, risk factors, and outcomes of this vulnerable group. METHODS: Internal Medicine patients aged >75 years who were admitted via the Emergency Department to a tertiary hospital between January 2015 to December 2018 and who activated a MET call were compared to patients without MET call activation during the same time period. Outcome measures included management post-MET call, Intensive Care Unit (ICU) admission rates, discharge disposition, length of hospital stays (LOS), and in-patient mortality. RESULTS: There were 10,803 Internal Medical admissions involving 10,423 patients; median age 85 (IQR 81-89) years. Of these, 995 (10%) patients received at least one MET call. MET call patients had greater physiological instability in the Emergency Department and higher median Charlson comorbidity index values (2, IQR 1-3 vs. 1, IQR 0-2; p < .0001) than non-MET call patients. Overall, 10% of MET call patients were admitted to ICU. MET patients had a longer median length of stay (9 [IQR 5-14] vs. 4 days [IQR 2-7]; p < .001) and higher in-hospital mortality (29% vs. 7%; p < .001). However, mortality of MET call patients without treatment limitations was 48/357 (13%). CONCLUSION: One in ten Internal Medicine patients aged >75 years and admitted via ED had a MET call. Physiological instability in ED and comorbidities were key risk factors. Mortality in MET patients approached 30%. These data can help predict at-risk patients for improving goals of care and pre-MET interventions.

Registrar triage, communication and moral distress during end-of-life care rapid response team calls in a teaching hospital.

BACKGROUND: Approximately one-third of rapid response teams (RRT) involve end-of-life care (EOLC) issues. Intensive care unit (ICU) registrar experience in such calls is underinvestigated. AIMS: To evaluate the proportion of RRT calls triaged as relating to EOLC issues, issues around communication regarding prognostication, registrar self-reported moral distress and associations between RRT EOLC classification and patient outcomes. METHODS: Prospective observational study of RRT calls in a tertiary referrals hospital between December 2016 and January 2017 using a standardised case report form and data from an electronic RRT database. RESULTS: There were 401 RRT calls in the study period, and data were available for 270 (67%) calls, of which 72%, 10% and 18% were triaged as 'obviously not EOLC call', 'obvious EOLC call' and 'uncertain EOLC call' respectively. Most discussions regarding prognostication occurred between registrars, and more than half (55%) were with a covering doctor. Consensus on prognostication was achieved in 93% cases. Registrars reported distress in 19% of calls that obviously related to EOLC and 22% of calls that were uncertain, compared with <1% of calls that were obviously not relating to EOLC. Inhospital mortality was 6%, 67% and 39% for obviously not EOLC, obvious EOLC and uncertain EOLC calls respectively. CONCLUSIONS: EOLC issues occur commonly in RRT calls and are often associated with moral distress to ICU registrars. Although consensus on prognostication is usually achieved, conversations often involve covering doctors. These issues impact on the ICU registrar experience of RRT calls and require further exploration.

Practice patterns and predictors of outpatient care following acute kidney injury in an Australian healthcare setting.

BACKGROUND: Survivors of acute kidney injury (AKI) are at increased risk of major adverse kidney events and international guidelines recommend individuals be evaluated 3 months following AKI. AIM: We describe practice patterns and predictors of post-AKI care in an Australian tertiary hospital. METHODS: A retrospective analysis was undertaken of adults with AKI (defined by KDIGO criteria) admitted to a single centre between 2012 and 2016. The primary outcome was outpatient nephrology review at 3 months. Secondary outcomes included inpatient nephrology review, and outpatient serum creatinine and urinary protein measurements. Data were analysed using multivariable logistic and competing risk regression. RESULTS: Only 117 of 2111 (6%) patients with AKI were reviewed by a nephrologist at 3 months. Reviewed patients were more likely to have a higher discharge serum creatinine (odds ratio (OR) 1.20 per 10 µmol/L increase; 95% confidence interval (CI) 1.16-1.25) or a history of peripheral vascular disease (OR 1.77; 95% CI 1.00-3.14). They were less likely to be older (OR 0.66 per decade; 95% CI 0.57-0.76) or to have a history of liver (OR 0.47; 95% CI 0.26-0.87) or ischaemic heart (OR 0.50; 95% CI 0.27-0.94) disease. AKI stage did not predict follow up. The median time from discharge to outpatient serum creatinine testing was 12 days (interquartile range 4-47) and proteinuria was measured in 538 (25%) patients. CONCLUSIONS: A minority of admitted AKI patients receive recommended post-AKI care. Studies in other Australian institutions are required to confirm or refute these concerning findings.

Estimating baseline kidney function in hospitalized adults with acute kidney injury.

AIM: Baseline serum creatinine values are required to diagnose acute kidney injury but are often unavailable. We evaluated four conventional equations to estimate creatinine. We then developed and validated a new equation corrected by age and gender. METHODS: We retrospectively examined adults who, at first hospital admission, had available baseline creatinine data and developed acute kidney injury ≥24 h after admission. We split the study population: 50% (derivation) to develop a new linear equation and 50% (validation) to compare against conventional equations for bias, precision, and accuracy. We stratified analyses by age and gender. RESULTS: We studied 3139 hospitalized adults (58% male, median age 71). Conventional equations performed poorly in bias and accuracy in patients aged <60 or ≥75 (68% of the study population). The new linear equation had less bias and more accuracy. There were no clinically significant differences in precision. The median (95% confidence interval) difference in creatinine values estimated via the new equation minus measured baselines was 0.9 (-3.0, 5.9) and -0.5 (-7.0, 3.7) µmol/L in female patients 18-60 and 75-100, and -1.5 (-4.2, 2.2) and -7.8 (-12.7, -3.6) µmol/L in male patients 18-60 and 75-100, respectively. The new equation improved reclassification of KDIGO AKI stages compared to the MDRD II equation by 5.0%. CONCLUSION: Equations adjusted for age and gender are less biased and more accurate than unadjusted equations. Our new equation performed well in terms of bias, precision, accuracy, and reclassification.

Clinical impact of genomic testing in patients with suspected monogenic kidney disease.

PURPOSE: To determine the diagnostic yield and clinical impact of exome sequencing (ES) in patients with suspected monogenic kidney disease. METHODS: We performed clinically accredited singleton ES in a prospectively ascertained cohort of 204 patients assessed in multidisciplinary renal genetics clinics at four tertiary hospitals in Melbourne, Australia. RESULTS: ES identified a molecular diagnosis in 80 (39%) patients, encompassing 35 distinct genetic disorders. Younger age at presentation was independently associated with an ES diagnosis (p < 0.001). Of those diagnosed, 31/80 (39%) had a change in their clinical diagnosis. ES diagnosis was considered to have contributed to management in 47/80 (59%), including negating the need for diagnostic renal biopsy in 10/80 (13%), changing surveillance in 35/80 (44%), and changing the treatment plan in 16/80 (20%). In cases with no change to management in the proband, the ES result had implications for the management of family members in 26/33 (79%). Cascade testing was subsequently offered to 40/80 families (50%). CONCLUSION: In this pragmatic pediatric and adult cohort with suspected monogenic kidney disease, ES had high diagnostic and clinical utility. Our findings, including predictors of positive diagnosis, can be used to guide clinical practice and health service design.