Urinary Catheter

We conducted a two-stage program in which we first collected blood and urine samples from three distinct cohorts (Discovery study) to identify novel protein biomarkers for AKI. These single-center studies were used to identify the best biomarkers among 340 proteins, including novel candidates and previously described biomarkers such as kidney injury marker-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), cystatin-C, interleukin-18 (IL-18), pi-glutathione S-transferase (pi-GST), and liver fatty acid-binding protein (L-FABP). Data from all three cohorts were pooled for analysis. A fourth cohort (Sapphire study) was assembled from 35 clinical sites in North America and Europe and used to validate the performance of the best biomarkers (urine tissue inhibitor of metalloproteinases-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7)) from the Discovery study (Figure 1). The Sapphire study was approved by the Western Institutional Review Board (Olympia, Washington, USA). In addition, the study protocols were approved by investigational review boards/ethics committees as required, by each participating institution. All subjects (or authorized representatives) provided written informed consent.
The Sapphire study was designed and reported according to the STROBE guidelines [9 (link)]. As shown in Figure 1, the Discovery study enrolled patients who were admitted to an intensive care unit (any type), were at least 18 years of age and typically had at least one recognized risk factor for AKI. The Sapphire (validation) study enrolled critically ill patients who were at least 21 years of age, admitted to the intensive care unit within 24 hours of enrollment, expected to remain in the ICU with a urinary catheter for at least 48 hours and were critically ill (respiratory or cardiovascular dysfunction). Patients with known existing moderate or severe AKI (KDIGO [6 ] stage 2 or 3) were excluded. Sample size for the Sapphire study was based on the results of the Discovery study and is explained in detail in Additional file 1.

Medical devices like urinary catheter or IV-catheter or chest tube or NG-tube or mechanical/nasal ventilator.

Both patients and family members completed the questionnaires about sociodemographic and ACP attitudes, and functional capacity assessment by comprehensive geriatric assessment (CGA) was only investigated by the patients. Patients and family members separately expressed their own perspectives on ACP through face-to-face interviews.
Sociodemographic data including age, sex, marital status (categorized by married, divorced, widow, or single), educational level (classified as high school or below), medical insurance, religion, the relationship between patients and caregivers, self-reported family support (coded as poor, fair, and good), self-reported health status (coded as poor, fair, and good), concurrent diseases (including coronary artery disease, hypertension, diabetes, cerebrovascular disease, respiratory disease, and osteoarticular diseases), and prescription medications were recorded.
The functional capacity assessment was conducted by CGA based on the Chinese expert consensus recommendation (20 (link)). In this study, the activity of daily living was assessed by the Modified Barthel Index (MBI), and the higher the MBI score indicated the better the activity of daily living (21 (link)). The Short-Form Mini-Nutritional Assessment (MNA-SF) was used to ascertain the degree of malnutrition risk (22 (link)). Depressive symptoms were evaluated using the 15-item Geriatric Depression Scale (GDS-15), with higher scores indicating more depressive symptoms (23 (link)). Cognitive function was assessed using the Mini-Mental State Examination (MMSE) (24 (link)). Higher MMSE score indicated better cognitive function. Frailty was detected by the Clinical Frailty Scale (CFS) which was scored from 1 (very fit) to 9 (severely frail) (25 (link)). Based on the clinical judgment, a higher CFS score was considered a higher degree of frailty. The SARC-F questionnaire was used to screen sarcopenia, with higher values indicating a greater likelihood of sarcopenia (26 (link)).
A structured questionnaire about ACP attitudes was completed independently by patients and their family members. The questionnaire included prior experience with relatives and friends being rescued (coded as yes or no), attitudes toward death (categorized by fear, avoid discussing, and accept discussing), ACP knowledge, determination surrogate, value statement about end-of-life (coded as active treatment, relieving uncomfortable symptoms, maintenance of daily function, and quality of life or unknown), preferences for end-of-life treatments (including cardiopulmonary resuscitation, invasive mechanical ventilation support, non-invasive ventilation support, renal replacement therapy, gastrointestinal colostomy, nasal tube, deep vein catheterization, urinary catheter, and transfusion), and desired place of death. Discordance attitudes were defined based on patients' and family members' responses to the question about whether to consider ACP engagement of patients if patients cannot make decisions due to a medical condition (such as coma).