Functional reference limits describe key changes in the physiological relationship between a pair of physiologically related components. Statistically, this can be represented by a significant change in the curvature of a mathematical function or curve (e.g., an observed plateau). The point at which the statistical relationship changes significantly is the point of curvature inflection and can be mathematically modeled from the relationship between the interrelated biomarkers. Conceptually, they reside between reference intervals, which describe the statistical boundaries of a single biomarker within the reference population, and clinical decision limits that are often linked to the risk of morbidity or mortality and set as thresholds. Functional reference limits provide important physiological and pathophysiological insights that can aid laboratory result interpretation. Laboratory professionals are in a unique position to harness data from laboratory information systems to derive clinically relevant values. Increasing research on and reporting of functional reference limits in the literature will enhance their contribution to laboratory medicine and widen the evidence base used in clinical decision limits, which are currently almost exclusively contributed to by clinical trials. Their inclusion in laboratory reports will enhance the intellectual value of laboratory professionals in clinical care beyond the statistical boundaries of a healthy reference population and pave the way to them being considered in shaping clinical decision limits. This review provides an overview of the concepts related to functional reference limits, clinical examples of their use, and the impetus to include them in laboratory reports.

COVID-19 ; Heart Diseases ; Humans ; Incidence ; SARS-CoV-2 ; Singapore/epidemiology*

INTRODUCTIONProlonged stay in acute hospitals increases the risk of hospital-acquired infections in older patients, and disrupts patient flow and access to care due to bed shortages. We aimed to investigate the factors associated with prolonged length of stay (pLOS) among older patients (aged ≥ 78 years) in a tertiary hospital, to identify the potentially modifiable risk factors that could direct interventions to reduce length of stay (LOS).

METHODSDuring a three-month period from January 2013 to March 2013, we identified 72 patients with pLOS (LOS ≥ 21 days) and compared their demographic and clinical variables with that of 281 randomly selected control patients (LOS < 21 days) using univariate and multivariate logistic regression analyses.

RESULTSThe mean age of the patients was 85.30 ± 5.34 years; 54% of them were female and 72% were of Chinese ethnicity. Logistic regression revealed the following significant factors for increased LOS: discharge to intermediate and long-term care services (odds ratio [OR] 9.22, 95% confidence interval [CI] 3.56-23.89; p < 0.001); increased severity of illness (OR 2.41, 95% CI 1.12-5.21; p = 0.025); and presence of caregiver stress (OR 3.85, 95% CI 1.67-8.91; p = 0.002).

CONCLUSIONPresence of caregiver stress and nursing home placement are potential modifiable risk factors of pLOS among older patients. Early identification and management of caregiver stress, as well as expediting discharge planning, may help to reduce the length of stay for this cohort.

Aged ; Aged, 80 and over ; Caregivers ; Cross Infection ; epidemiology ; Female ; Health Services Accessibility ; Humans ; Length of Stay ; Male ; Random Allocation ; Regression Analysis ; Risk Factors ; Severity of Illness Index ; Singapore ; Social Class ; Stress, Psychological ; Tertiary Care Centers

PURPOSE: Wide-neck aneurysms (WNAs) associated with a dilated parent artery (PA) are not uncommon morphological abnormalities and usually cause inappropriate wall apposition and incomplete neck coverage of a tubular stent in stent-assisted coiling of aneurysms. We aimed to introduce a fusiform-shaped stent (FSS) and test its effectiveness in treating intracranial WNAs associated with a dilated PA using a three-dimensional (3D) model. MATERIALS AND METHODS: Two FSS types were designed with the middle one-third segment dilated by 10% (FSS10) and 20% (FSS20) and were compared with the tubular-shaped stent (TSS). A patient-specific 3D WNA model was prototyped and produced, and in vitro stent placement was performed. Angiographic images of the three stent types were analyzed and compared using predetermined parameters. RESULTS: The stent lumens were significantly larger in FSS10 and FSS20 than in TSS in the middle segments (P=0.046), particularly FSS20 (P=0.018). The non-covered area at the ostium tended to be smaller in FSS10 and FSS20 than in TSS, but the difference was not significant (P>0.05). The stent length was significantly longer in FSS10 and FSS20 than in TSS. The stent cell size was significantly larger in FSS than in TSS. CONCLUSION: Better vessel wall apposition and aneurysmal neck coverage was observed for FSS than for TSS. No significant difference was observed between FSS10 and FSS20.
Aneurysm ; Arteries ; Cell Size ; Endovascular Procedures ; Humans ; In Vitro Techniques* ; Intracranial Aneurysm* ; Neck ; Parents ; Stents*

INTRODUCTION: This study aimed to assess the effectiveness of the emergency department observation unit (EDOU) for patients with acute pyelonephritis in a Singapore tertiary academic medical centre. METHODS: We reviewed the clinical records of consecutive patients who presented with pyelonephritis between 1 July 2012 and 31 October 2014 to collect information on demographics, symptoms, signs, laboratory and radiological results, treatment, and clinical outcomes. RESULTS: Of 459 emergency department (ED) patients who were identified as having pyelonephritis, 164 (35.7%) were managed in the EDOU. Successful management in the EDOU was achieved in 100 (61.0%) patients. Escherichia coli was the predominant (64.6%) micro-organism in urine cultures and was positive in 106 patients. Patients diagnosed with acute pyelonephritis who were successfully managed in the EDOU had a lower incidence of nausea (32.0% vs. 60.9%, p < 0.001) and vomiting (15.0% vs. 50.0%, p < 0.001) compared to those who were not successful. CONCLUSION EDOU is useful for both observation and treatment of patients with acute pyelonephritis. Urine cultures are sufficient for the identification of the culprit micro-organism. Patients who present with prominent symptoms of vomiting should have routine administration of antiemetics, while consideration for second-line antiemetics is recommended for those with persistent symptoms.