ABSTRACT
BACKGROUND: Acute kidney injury (AKI) is a common manifestation among patients critically ill with SARS-CoV-2 infection (Coronavirus 2019) and is associated with significant morbidity and mortality. The pathophysiology of renal failure in this context is not fully understood, but likely to be multifactorial. The intensive care unit outcomes of patients following COVID-19 acute critical illness with associated AKI have not been fully explored. We conducted a cohort study to investigate the risk factors for acute kidney injury in patients admitted to and intensive care unit with COVID-19, its incidence and associated outcomes. METHODS: We reviewed the medical records of all patients admitted to our adult intensive care unit suffering from SARS-CoV-2 infection from 14th March 2020 until 12th May 2020. Acute kidney injury was defined using the Kidney Disease Improving Global Outcome (KDIGO) criteria. The outcome analysis was assessed up to date as 3rd of September 2020. RESULTS: A total of 81 patients admitted during this period. All patients had acute hypoxic respiratory failure and needed either noninvasive or invasive mechanical ventilatory support. Thirty-six patients (44%) had evidence of AKI (Stage I-33%, Stage II-22%, Renal Replacement Therapy (RRT)-44%). All patients with AKI stage III had RRT. Age, diabetes mellitus, immunosuppression, lymphopenia, high D-Dimer levels, increased APACHE II and SOFA scores, invasive mechanical ventilation and use of inotropic or vasopressor support were significantly associated with AKI. The peak AKI was at day 4 and mean duration of RRT was 12.5 days. The mortality was 25% for the AKI group compared to 6.7% in those without AKI. Among those received RRT and survived their illness, the renal function recovery is complete and back to baseline in all patients. CONCLUSION: Acute kidney injury and renal replacement therapy is common in critically ill patients presenting with COVID-19. It is associated with increased severity of illness on admission to ICU, increased mortality and prolonged ICU and hospital length of stay. Recovery of renal function was complete in all survived patients.
Subject(s)
Acute Kidney Injury/etiology , COVID-19/complications , APACHE , Acute Kidney Injury/epidemiology , Acute Kidney Injury/mortality , Acute Kidney Injury/therapy , COVID-19/epidemiology , Cohort Studies , Critical Illness , Female , Hospital Mortality , Humans , Incidence , Intensive Care Units , Male , Middle Aged , Organ Dysfunction Scores , Recovery of Function , Renal Replacement Therapy/statistics & numerical data , Respiration, Artificial/adverse effects , Risk Factors , Water-Electrolyte BalanceABSTRACT
Background: Acute kidney injury (AKI) is a significant complication of COVID-19 infection. UK NICE guidelines have been developed. Aim: to examine our local patientlevel COVID-19 Hospitalisation in England Surveillance System (CHESS) database to elucidate potential risk factors for AKI vs guidelines. Methods: 564 COVID positive admissions between 7 March-24 May 2020 at University Hospital Southampton were examined using Python (Anacondas distribution) and SPSSTM. AKI was staged by RIFLE and AKIN criteria consistent with NICE guidance. X2, t-test, Mann-Whitney U test and logistic regression were used to analyse the data. Results: AKI was present in 177 patients (31%). At peak, 108 (61%) stage 1;42 (24%) stage 2;27 (15%) stage 3. There were no significant differences in cohorts with respect to white vs non-white ethnicity, gender, obesity or anti-COVID-19 treatment. 44% of patients with AKI died vs 19% in the non-AKI group (p<0.001). AKI was associated with ICU admission (27% vs 10% p<0.001), requirement of non-invasive (13% vs 4%) and invasive ventilation (14% vs 4%) (both p<0.001). Prior diabetes (18% vs 8%), hypertension (47% vs 34%), chronic respiratory and cardiac disease (both 25% vs 15%) were more common in the AKI group (p<0.004). Increased age was associated with AKI (p=0.02) and length of stay (LOS) positively correlated to AKI stage(p<0.001). Peak levels of biomarkers: ferritin, D-dimer, C-reactive protein, high sensitivity troponin-I, neutrophil count and total white cell count, were all significantly raised (p<0.001) in the AKI group, increasing with stage of AKI (p<0.001). However, in multivariable analysis first clinical observations, neutrophil count, haemoglobin, D-Dimer and albumin came out as the most significant predictors of AKI: Specificity 88.7%, Sensitivity 43.6%. Conclusions: AKI is a frequent complication of COVID-19 and we identified similar risk factors to those in the NICE guidelines. In addition, we found hypertension and chronic respiratory disease to increase risk of AKI whilst ethnicity, gender, obesity and COVID-19 treatments did not. Furthermore, AKI was associated with increased mortality, ICU admissions and LOS, concordant with previous studies. This data also points to several biomarkers as possible predictors of AKI development and severity. Further analysis of this data is ongoing.