A comparison of human and GPT-4 use of probabilistic phrases in a coordination game.

English speakers use probabilistic phrases such as likely to communicate information about the probability or likelihood of events. Communication is successful to the extent that the listener grasps what the speaker means to convey and, if communication is successful, individuals can potentially coordinate their actions based on shared knowledge about uncertainty. We first assessed human ability to estimate the probability and the ambiguity (imprecision) of twenty-three probabilistic phrases in a coordination game in two different contexts, investment advice and medical advice. We then had GPT-4 (OpenAI), a Large Language Model, complete the same tasks as the human participants. We found that GPT-4's estimates of probability both in the Investment and Medical Contexts were as close or closer to that of the human participants as the human participants' estimates were to one another. However, further analyses of residuals disclosed small but significant differences between human and GPT-4 performance. Human probability estimates were compressed relative to those of GPT-4. Estimates of probability for both the human participants and GPT-4 were little affected by context. We propose that evaluation methods based on coordination games provide a systematic way to assess what GPT-4 and similar programs can and cannot do.

The clinical journey and healthcare resources required for dialysis access of end-stage kidney disease patients during their first year of hemodialysis.

BACKGROUND: Creation and maintenance of dialysis vascular access (VA) is a major component of healthcare resource utilization and cost for patients newly started on hemodialysis (HD). Different VA format arises due to patient acceptance of anticipatory care versus late preparation, and clinical characteristics. This study reviews the clinical journey and resource utilization required for different VA formats in the first year of HD. METHOD: Data of patients newly commenced on HD between July 2015 and June 2016 were reviewed. Patients were grouped by their VA format: (A) pre-emptive surgically created VA (SCVA), (B) tunneled central venous catheter (CVC) followed by SCVA creation, (C) long-term tunneled CVC only. Clinical events, number of investigations and procedures, hospital admissions, and incurred costs of the three groups were compared. RESULTS: In the multivariable analysis, the cost incurred by the group A patients had no significant difference to that incurred in the group B patients (p = 0.08), while the cost of group C is significantly lower (p < 0.001). Both the 62.7% of group A with successful SCVA who avoided tunneled CVC usage, and those with a functionally matured SCVA in group B (66.1%), used fewer healthcare resources and incurred less cost for their access compared to those did not (p = 0.01, p = 0.02, respectively) during the first year of HD. CONCLUSION: With comparable cost, a pre-emptive approach enables avoidance of tunneled CVC. Tunneled CVC only access format incurred lower cost and is suitable for carefully selected patients. Successful maturation of SCVA greatly affects patients' clinical journey and healthcare cost.

Transitional care program to facilitate recovery following severe acute kidney injury.

BACKGROUND: Patients with acute kidney injury needing prolonged renal replacement therapy (AKI-RRT) may benefit from a structured care process in form of an AKI transitional care program (ATCP), to facilitate RRT weaning and recovery. METHODS: We examined outcomes following ATCP implementation in adults with AKI-RRT from a tertiary institution (versus pre-ATCP controls), including mortality, cumulative hospital days, and renal function over one year; RRT and haemodialysis catheter days in initial 90 days. RESULTS: We studied 89 patients with age 62 ( ± 15) years. 47% had septic AKI, 20% cardiorenal syndrome, and 29% had baseline eGFR < 30 mL/min/1.73 m2. Comparing 45 ATCP patients with 44 controls: 64% and 45% received continuous RRT (CRRT) (p = 0.07), with comparable rates of heart failure (24% versus 25%), ICU care (67% versus 70%), RRT successfully weaned (71% versus 75%), respectively; corresponding mortality rates were 24% and 32% (p = 0.44), hospital days of 205 (197-213) and 223 (215-232) per 1000 patient-days alive over one year (p = 0.002); with comparable RRT and catheter days. Serial serum creatinine in months following RRT cessation were comparable between either survivor-group. On multivariate analysis, heart failure or having received CRRT independently predicted mortality and longer hospital days (p < 0.05); ATCP was independently associated with reduced hospital days (p < 0.001). 17 ATCP patients and 14 controls required outpatient RRT weaning, with catheter days of 607 (568-648) and 683 (638-731) per 1000 patient-days in initial 90 days, respectively (p = 0.01). CONCLUSIONS: Implementing a structured care pathway in patients with AKI-RRT may help reduce hospitalization, and reduce haemodialysis catheter days in the subgroup for outpatient RRT weaning.

Intravenous maintenance fluid tonicity and hyponatremia after major surgery- a cohort study.

BACKGROUND: Intravenous maintenance fluid (IMF) tonicity and composition influence plasma electrolyte balance. OBJECTIVE: To determine if hypotonic IMF therapy contributes to post-surgical hyponatremia. SETTING: Single-center tertiary institution. PARTICIPANTS: Adults who underwent major surgery and received peri-surgical IMF, with exclusive administration of hypotonic pre-mixed 0.33% saline, 5% dextrose and potassium chloride (DK0.33%S), or isotonic 0.9% saline with or without 5% dextrose (NS/DNS). OUTCOMES AND MEASURES: We examined post-surgical hyponatremia, hypokalemia and acute kidney injury (AKI), associated with use of either IMF. RESULTS: We studied 659 patients, of whom 161 patients (24%) developed post-surgical hyponatremia. DK0.33%S (versus NS/DNS) IMF was administered in 52% of patients who developed hyponatremia, compared to 38% of patients with stable natremia (p = 0.001). More patients with hyponatremia underwent gastrointestinal-hepatobiliary or abdominal (GI/HBS/Abd) surgery versus other surgical-sites (p = 0.001). Hypokalemia developed in 1% versus 10% of patients who received DK0.33%S and NS/DNS IMF respectively (p< 0.001), with corresponding AKI rates of 3% versus 7% (p = 0.02). On multivariate analysis, adjusted for timing of biochemistry post-surgery, IMF infusion rate and volume; independent factors associated with post-surgical hyponatremia included DK0.33%S administration, GI/HBS/Abd surgery (versus other sites), and post-surgical AKI (p < 0.05). Subgroup analysis by surgical sites showed that association of DK0.33%S administration with hyponatremia was most evident in GI/HBS/Abd surgery. CONCLUSIONS: Administration of DK0.33%S IMF, compared with NS/DNS, is associated with post-surgical hyponatremia in adults after major surgery, but with less hypokalemia. The higher rate of AKI observed with NS/DNS IMF requires further evaluation.

Predicting first-year mortality in incident dialysis patients with end-stage renal disease - the UREA5 study.

We aimed to develop a risk prediction model for first-year mortality (FYM) in incident dialysis patients with end-stage renal disease. We retrospectively examined patient comorbidities and biochemistry, prior to dialysis initiation, using a single-center, prospectively maintained database from 2005-2010, and analyzed these variables in relation to FYM. A total of 983 patients were studied. 22% had left ventricular ejection fraction (LVEF) <45%. FYM was 17%, and independent predictors included URate <500 or >600 µmol/l, LVEF <45% (higher odds ratio if <30%), Age >70 years, Arteriopathies (cerebrovascular and/or peripheral-vascular diseases), serum Albumin <30 g/l, and Alkaline phosphatase >80 U/l (p < 0.05, C-statistic 0.74), and these constitute the acronym UREA5. Using linear modeling, risk weightage/integer of 3 was assigned to LVEF <30%, 2 to age >70 years, and 1 to each remaining variable. Cumulative UREA5 scores of ≤ 1, 2, 3, 4, and ≥ 5 were associated with FYM of 6, 8, 22, 31, and 46%, respectively (p < 0.0001). Increasing UREA5 scores were strongly associated with stepwise worsening of FYM after dialysis initiation.

Microbiology of tunnelled catheter-related infections in a multi-ethnic South-east Asian patient population.

INTRODUCTION: Clinical practice guidelines recommend empiric antibiotic therapy for suspected tunnelled haemodialysis catheter-related infections (CRI), and the choice of antibiotics should be adjusted according to the local microbiological profile and antimicrobial sensitivities. We aim to describe the microbiology, antibiotic sensitivities, and clinical outcomes of CRI with tunnelled haemodialysis catheters in a multi-ethnic South-East Asian population. METHODS: Using a prospective vascular access registry, we identified 99 patients who had catheters removed for suspected or confirmed CRI (50.5% male, mean age 56.9 years) from January 1, 2007, till May 2009. We retrospectively retrieved microbiology, mortality and echocardiography data from the hospital electronic databases. RESULTS: There were 115 removal-unique cultures that yielded 75.7% Gram-positive and 24.3% Gram-negative isolates (15 removals were polymicrobial). Organisms isolated were methicillin-resistant Staphylococcus aureus (MRSA) 28.6%, methicillin-sensitive S. aureus 26.5%, coagulase-negative staphylococci 21.4%, Pseudomonas aeruginosa 10.2%, and others. Out of 8 patients who died, 7 had MRSA. Risk factors associated with mortality were Chinese race (p = 0.03), MRSA infection (p < 0.001), and older age (p < 0.001). CONCLUSION: Gram-positive isolates accounted for most tunnelled CRI and MRSA was highly associated with death. In sick patients presenting with suspected CRI, the preferred empiric antibiotic regimen should include agents active against both MRSA and P. aeruginosa.

Profile of hospitalisation and death in the first year after diagnosis of end-stage renal disease in a multi-ethnic Asian population.

INTRODUCTION: The increasing prevalence of end-stage renal disease (ESRD) is an important public health issue due to the high costs of kidney replacement therapies. We examined the impact of ethnicity and other factors in ESRD management and hospitalisation in a multiracial Asian population in the fi rst year after diagnosis. MATERIALS AND METHODS: We analysed a prospectively collected database of 168 new ESRD patients from the National University Hospital, Singapore (NUH) in 2005. Univariate and multivariate analyses were performed to assess factors for mortality and hospitalisation. RESULTS: Sixteen patients eventually chose conservative treatment, 102 haemodialysis, 41 peritoneal dialysis and 9 patients underwent kidney transplantation for their long-term treatment. Although more Chinese patients had dialysis plans (56.7% vs 36.8%, P = 0.022), many still required urgent dialysis initiation via catheters (61.3%). These dialysed patients who required urgent treatment had more admissions (3.6 vs 2.6, P = 0.023) and longer length of stay (9.3 days, P = 0.014). Approximately 40 (7.4%) admissions were related to vascular access complications (thromboses, dislodgements and infections), and 15 (2.8%) were for new tunnelled catheter insertions. Deaths were 23.8% in the fi rst year after diagnosis and median survival was 125 days. Age, fi nal treatment modality, type of therapy centre, history of coronary artery disease, left ventricular ejection fraction (LVEF) <50%, and having no plans for dialysis were associated with mortality. CONCLUSIONS: The care of ESRD patients requires substantial commitment of healthcare resources particularly in the fi rst year after diagnosis. Steps to reduce urgent initiation of dialysis will help reduce resource utilisation and improve patient outcomes.