Timothy Rainer | Cardiff University (original) (raw)

Papers by Timothy Rainer

Research paper thumbnail of What is the relationship between the Glasgow coma scale and airway protective reflexes in the Chinese population?

Research paper thumbnail of Outcome after implementation of sepsis guideline in the emergency department of a university hospital in Hong Kong

Hong Kong Journal of Emergency Medicine, May 2015

Introduction: Internationally, standard care of patients with severe sepsis consists of early det... more Introduction: Internationally, standard care of patients with severe sepsis consists of early detection, early antimicrobial therapy, and aggressive intravenous fluid therapy to maintain tissue oxygenation and perfusion. In this retrospective study, we aimed to examine the management of patients with severe sepsis in a local university hospital emergency department before and after the implementation of a sepsis management guideline. Method: We collected data on the management and outcome of patients during a three-month period before the implementation of a sepsis guideline (October-December 2009). We then collected similar data one year after the implementation (October-December 2010). Key sepsis management areas and in- hospital mortality rates were compared, as were length of resuscitation, three-month mortality rate, hospital length of stay (LOS) and intensive care unit (ICU) LOS. Results: Data from 115 patients were collected in the pre-implementation group, while data on 102 patients were collected for the post-implementation group. There were more patients with hypoperfusion in the post-implementation cohort (25.2% vs. 40.2%, p=0.019). There was no difference in background characteristics, average lactate value, average MAP or number of hypotensive patients between the two groups. Significantly more antibiotics were given after the intervention (13.0% vs. 23.5%, p=0.045) and more patients had a lactate level measured (43.0% vs. 73.5%; p<0.001). There was a trend towards better survival for a subgroup of patients with hypoperfusion (48.0% vs. 29.2%, p=0.060). Conclusions: Implementation of a sepsis guideline leads to more antibiotics being given and more lactate measurement in the emergency department. (Hong Kong j.emerg.med. 2015;22: 163-171)
LOS

Research paper thumbnail of Plasma DNA as a prognostic marker in trauma patients

Clinical chemistry, 2000

Recently, much interest has developed in the potential use of plasma DNA as a diagnostic and moni... more Recently, much interest has developed in the potential use of plasma DNA as a diagnostic and monitoring tool. We hypothesized that plasma DNA is increased in patients with trauma and may be prognostic in such patients. We studied 84 patients who had sustained an acute blunt traumatic injury. We measured plasma DNA by a real-time quantitative PCR assay for the beta-globin gene. Blood samples were collected at a median time of 60 min following injury. Blood samples were also obtained from 27 control subjects. The median plasma DNA concentrations in the control, minor/moderate trauma (Injury Severity Score <16; n = 47), and major trauma (Injury Severity Score > or =16; n = 37) groups were 3154 kilogenome-equivalents/L, 13 818 kilogenome-equivalents/L, and 181 303 kilogenome-equivalents/L, respectively. Plasma DNA concentrations in patients with adverse outcomes, including acute lung injury, acute respiratory distress syndrome, and death, had 11. 6- to 12-fold higher plasma DNA co...

Research paper thumbnail of Neopterin Screening to Improve Safety of Blood Transfusion

Research paper thumbnail of Hemodynamic measurements for evaluating vasovagal syncope in the emergency department

Clinical and Experimental Emergency Medicine, 2015

Research paper thumbnail of Abdominal thrusts are not recommended for infants with foreign body airway obstruction

Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine, 2009

Research paper thumbnail of Prospective validation of Thrombolysis in Myocardial Infarction and front door Thrombolysis in Myocardial Infarction risk scores in Chinese patients presenting to the ED with chest pain

The American journal of emergency medicine, 2014

Chest pain is a common complaint among emergency department (ED) patients. The Thrombolysis in My... more Chest pain is a common complaint among emergency department (ED) patients. The Thrombolysis in Myocardial Infarction (TIMI) and front door TIMI (FDTIMI) scores are used to risk stratify chest pain patients in many Western countries; they have not been validated in patients with undifferentiated chest pain in Asia. Our objective was to establish the relationship between the TIMI and FDTIMI scores and the 30 day rate of major adverse cardiac outcomes (MACE) in Chinese patients presenting to the ED with chest pain. Prospective, single-center, observational cohort study of consecutive patients presenting with chest pain from July 2009 until March 2010 to a Hong Kong university hospital ED. Data collected included patient characteristics, TIMI items and past medical and medication history. Primary outcome was MACE within 30 days of presentation. MACE was a composite outcome of any of the following: death (all causes), readmission with myocardial infarction, acute coronary syndrome not di...

Research paper thumbnail of Cost-effectiveness of Dermabond versus sutures for lacerated wound closure: a randomised controlled trial

Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine, 2011

Research paper thumbnail of Emergency department intervention for high-risk elders: identification strategy and randomised controlled trial to reduce hospitalisation and institutionalisation

Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine, 2011

Research paper thumbnail of Ethics and analgesia

Emergency medicine journal : EMJ, 2009

The user has requested enhancement of the downloaded file.

Research paper thumbnail of Circulating nucleic acid analysis: diagnostic applications for acute pathologies

Acta neurochirurgica. Supplement, 2005

Much research interest has been shown in recent years for the development of molecular diagnostic... more Much research interest has been shown in recent years for the development of molecular diagnostic strategies based on the analysis of DNA/RNA molecules that are present in the plasma/serum of human subjects. Reported applications include the diagnosis, prognostication or monitoring of malignancies and pregnancy-associated complications. While researchers have speculated that cell death is a potential mechanism that leads to the release of DNA/RNA into the circulation, studies have demonstrated that indeed increased amounts of plasma DNA and RNA could be detected in patients sustaining acute traumatic injuries. The degree of plasma DNA elevation correlated with the severity of injury. Similarly, plasma DNA concentrations have been shown to correlate with indices of prognostic significance in patients with acute stroke. It is expected that new diagnostic markers based on plasma RNA detection could be developed for the evaluation of acute pathologies.

Research paper thumbnail of Evaluation of the Recognition of Stroke in the Emergency Room (ROSIER) Scale in Chinese Patients in Hong Kong

PLoS ONE, 2014

Background and Purpose: The objective of this study was to determine the performance of the Recog... more Background and Purpose: The objective of this study was to determine the performance of the Recognition Of Stroke In the Emergency Room (ROSIER) scale in risk-stratifying Chinese patients with suspected stroke in Hong Kong.

Research paper thumbnail of Optical Properties of Ag and Au Nanoparticles Dispersed within the Pores of Monolithic Mesoporous Silica

The optical absorption of silver and gold nanoparticles dispersed within the pores of monolithic ... more The optical absorption of silver and gold nanoparticles dispersed within the pores of monolithic mesoporous silica upon annealing at elevated temperatures has been investigated. With decreasing particle size, the surface plasmon resonance position of the particles blue-shifts first and then red-shifts for silver/silica samples, but only red-shifts for gold/silica samples. This size evolution of the resonance position is completely different from that previously reported for fully embedded particles. We assume a local porosity at the particle/matrix interface, such that free surface of particles within the pores may be in contact with ambient air, and present a two-layer core/shell model to calculate the optical properties. These calculations also consider deviations from the optical constants of bulk matter to account for corresponding effects below about 10 nm particle size. From the good agreement between experimental results and model calculations, we conclude a peculiar particle/ambience interaction dominating the size evolution of the resonance. Because of the difference of core electron structure, the relative importance of the effects of local porosity and free surface, respectively, are different for silver and gold. For silver, the effect of the local porosity is stronger, but for gold the opposite is found.

Research paper thumbnail of Presence of filterable and nonfilterable mRNA in the plasma of cancer patients and healthy individuals

Clinical chemistry, 2002

As RNA is labile, we investigated whether circulating RNA in human plasma may be present in a par... more As RNA is labile, we investigated whether circulating RNA in human plasma may be present in a particle-associated form. Blood was collected from 27 healthy individuals and 16 hepatocellular carcinoma (HCC) patients. The plasma from each individual was processed by two means: filtration through filters with different pore sizes (from 5 microm to 0.22 microm) and ultracentrifugation. We assessed plasma RNA content by a real-time quantitative reverse transcription-PCR assay for glyceraldehyde-3-phosphate dehydrogenase (GAPDH) transcripts and plasma DNA by a real-time quantitative PCR assay for the beta-globin gene. The plasma GAPDH mRNA concentrations in the healthy individuals were significantly different in every pair of these filter sizes (P <0.05 for each pair). Overall, the plasma GAPDH mRNA concentration was higher by a median of 15-fold (interquartile range, 10- to 24-fold) in the paired unfiltered sample than in the sample filtered through a 0.22 microm filter. In contrast, ...

Research paper thumbnail of A Comparison of Functional Outcome in Patients Sustaining Major Trauma: A Multicentre, Prospective, International Study

PLoS ONE, 2014

Objectives: To compare 6 month and 12 month health status and functional outcomes between regiona... more Objectives: To compare 6 month and 12 month health status and functional outcomes between regional major trauma registries in Hong Kong and Victoria, Australia.

Research paper thumbnail of Age-specific non-invasive transcutaneous Doppler ultrasound derived haemodynamic reference ranges in elderly Chinese adults

Research paper thumbnail of Analysis of trends in emergency department attendances, hospital admissions and medical staffing in a Hong Kong university hospital: 5-year study

International journal of emergency medicine, Jan 8, 2009

The workload of emergency departments (ED) continually changes in response to presentations, over... more The workload of emergency departments (ED) continually changes in response to presentations, overcrowding and availability of expertise and investigations. To investigate changes in ED presentations and care processes, and the relationship of patient demand and ED staff resources to waiting times and processing times. Retrospective analysis of prospectively collected administrative data from January 1999 to April 2005 in an emergency department in a university teaching hospital in Hong Kong. All patients attending the emergency department during the study period were included. Monthly attendance data were retrieved and analysed to determine both qualitative and quantitative changes in the patterns of presentation to the ED using prospectively gathered data. Total ED attendances decreased by 25% during the study with little seasonal variation. The admission rate and the use of ambulances increased steadily and significantly. Medical patients are increasing proportionately, but trauma...

Research paper thumbnail of Evidence-based point-of-care diagnostics: Current status and emerging technologies

Point-of-care (POC) diagnostics brings tests nearer to the site of patient care. The turnaround t... more Point-of-care (POC) diagnostics brings tests nearer to the site of patient care. The turnaround time is short, and minimal manual interference enables quick clinical management decisions. Growth in POC diagnostics is being continuously fueled by the global burden of cardiovascular and infectious diseases. Early diagnosis and rapid initiation of treatment are crucial in the management of such patients. This review provides the rationale for the use of POC tests in acute coronary syndrome, heart failure, human immunodeficiency virus, and tuberculosis. We also consider emerging technologies that are based on advanced nanomaterials and microfluidics, improved assay sensitivity, miniaturization in device design, reduced costs, and high-throughput multiplex detection, all of which may shape the future development of POC diagnostics.

Research paper thumbnail of Leukocyte L-selectin is up-regulated after mechanical trauma in adults

Journal of Trauma-Injury Infection and Critical Care, 1998

Infection and multiple organ failure remain the principal causes of late mortality after trauma d... more Infection and multiple organ failure remain the principal causes of late mortality after trauma despite advances in the resuscitation of injured patients. Because a better understanding of postinjury leukocyte trafficking is essential to the development of possible therapeutic measures aimed at preventing these complications, we have performed a study of one factor in the early posttrauma endothelial adhesion behavior of monocytes, lymphocytes, and neutrophils: their cell surface expression of L-selectin (CD62L). We have also studied the plasma levels of soluble L-selectin in these patients. Two venous blood samples were taken from each of 41 trauma patients at median times of 1 and 20 hours after injury. The study group included 16 patients with major (Injury Severity Score (ISS) &gt; or = 16), 17 with moderate (ISS = 9-15), and 8 with minor (ISS &lt; 9) trauma. Cell surface L-selectin was measured on leukocyte subsets by staining with specific fluorescent-labeled monoclonal antibodies to CD62L and using flow cytometry. Both the percentage of cells expressing the molecule and the mean channel fluorescence were measured. Levels of soluble L-selectin were measured in the plasma, sampled concurrently, by enzyme-linked immunosorbent assay. Monocytes, lymphocytes, and neutrophils all showed an early increase in cell surface L-selectin expression as measured by mean channel fluorescence (p &lt; 0.0001, p &lt; 0.001, and p &lt; 0.0001, respectively), and this persisted in later samples taken at a median 20 hours after injury (p &lt; 0.0001,p &lt; 0.0001, and p &lt; 0.01). Only monocytes showed an increased percentage of cells expressing the molecule in the early phase (p &lt; 0.02), and this remained in the later phase (p &lt; 0.001). Monocytes also showed a further significant increase in mean channel fluorescence (p &lt; 0.02) between the two periods. No significant changes in levels of plasma soluble L-selectin were found at either stage. An increase in the expression of L-selectin on each of three leukocyte populations has been demonstrated in the early phase after trauma. This would tend to promote rolling behavior of leukocytes and increase their contact with the vascular endothelium. There were marked differences in the later responses of the three populations, which may represent differential control of their behavior.

Research paper thumbnail of Adrenaline upregulates monocyte L-selectin in vitro

Resuscitation, 1999

Although surface adhesion molecules mediate leucocyte-endothelial interactions at sites of inflam... more Although surface adhesion molecules mediate leucocyte-endothelial interactions at sites of inflammation, relatively little is known of the factors which increase the expression of L-selectin in circulating leucocytes. The expression of leucocyte L-selectin increases during acute stress events such as injury and is temporally related to an early neuroendocrine response. This study investigates whether adrenaline increases the expression of L-selectin on monocytes, neutrophils and lymphocytes in vitro and whether these effects are mediated via beta-adrenoceptors. A total of 20 ml of blood was withdrawn from 28 healthy volunteers (21 males) with a mean age of 29 years (range 23-67 years). Adrenaline at physiological doses mimicking trauma (0-200 nmol/l) was added to whole blood prior to immunofluorescent staining and analysis by flow cytometry. Propranolol (50 microl of 2 x 10(-5) M) was also added to separate tubes prior to incubation with adrenaline. Saline (40 microl 0.9% solution) was used as a control. Expression is described firstly as percentage of cells expressing L-selectin and secondly as average intensity (mean channel fluorescence, mcf) per cell expressing CD62L. Summary measures were used to analyse the data. A significant increase in both the percentage of monocytes expressing L-selectin and mean channel fluorescence of L-selectin was evident with adrenaline in vitro (P &amp;amp;lt; 0.0001). Maximal increases occurred at 100 nmol/l adrenaline when a 9% increase in the percentage of monocytes expressing L-selectin and a 23% increase in mean channel fluorescence were observed. These effects were both blocked by propranolol (P &amp;amp;lt; 0.0001). No significant differences were observed for neutrophils or lymphocytes except for a slight increase in the percent neutrophils expressing L-selectin, and a small decreasing trend in percent lymphocytes expressing L-selectin. Adrenaline upregulates the surface expression of L-selectin on monocytes in vitro, an effect which is partially mediated by beta-adrenoceptors. As monocytes initiate early aspects of the inflammatory response, these findings suggest that beta-blockade may have an inhibitory role for certain aspects of leucocyte trafficking.

Research paper thumbnail of What is the relationship between the Glasgow coma scale and airway protective reflexes in the Chinese population?

Research paper thumbnail of Outcome after implementation of sepsis guideline in the emergency department of a university hospital in Hong Kong

Hong Kong Journal of Emergency Medicine, May 2015

Introduction: Internationally, standard care of patients with severe sepsis consists of early det... more Introduction: Internationally, standard care of patients with severe sepsis consists of early detection, early antimicrobial therapy, and aggressive intravenous fluid therapy to maintain tissue oxygenation and perfusion. In this retrospective study, we aimed to examine the management of patients with severe sepsis in a local university hospital emergency department before and after the implementation of a sepsis management guideline. Method: We collected data on the management and outcome of patients during a three-month period before the implementation of a sepsis guideline (October-December 2009). We then collected similar data one year after the implementation (October-December 2010). Key sepsis management areas and in- hospital mortality rates were compared, as were length of resuscitation, three-month mortality rate, hospital length of stay (LOS) and intensive care unit (ICU) LOS. Results: Data from 115 patients were collected in the pre-implementation group, while data on 102 patients were collected for the post-implementation group. There were more patients with hypoperfusion in the post-implementation cohort (25.2% vs. 40.2%, p=0.019). There was no difference in background characteristics, average lactate value, average MAP or number of hypotensive patients between the two groups. Significantly more antibiotics were given after the intervention (13.0% vs. 23.5%, p=0.045) and more patients had a lactate level measured (43.0% vs. 73.5%; p<0.001). There was a trend towards better survival for a subgroup of patients with hypoperfusion (48.0% vs. 29.2%, p=0.060). Conclusions: Implementation of a sepsis guideline leads to more antibiotics being given and more lactate measurement in the emergency department. (Hong Kong j.emerg.med. 2015;22: 163-171)
LOS

Research paper thumbnail of Plasma DNA as a prognostic marker in trauma patients

Clinical chemistry, 2000

Recently, much interest has developed in the potential use of plasma DNA as a diagnostic and moni... more Recently, much interest has developed in the potential use of plasma DNA as a diagnostic and monitoring tool. We hypothesized that plasma DNA is increased in patients with trauma and may be prognostic in such patients. We studied 84 patients who had sustained an acute blunt traumatic injury. We measured plasma DNA by a real-time quantitative PCR assay for the beta-globin gene. Blood samples were collected at a median time of 60 min following injury. Blood samples were also obtained from 27 control subjects. The median plasma DNA concentrations in the control, minor/moderate trauma (Injury Severity Score <16; n = 47), and major trauma (Injury Severity Score > or =16; n = 37) groups were 3154 kilogenome-equivalents/L, 13 818 kilogenome-equivalents/L, and 181 303 kilogenome-equivalents/L, respectively. Plasma DNA concentrations in patients with adverse outcomes, including acute lung injury, acute respiratory distress syndrome, and death, had 11. 6- to 12-fold higher plasma DNA co...

Research paper thumbnail of Neopterin Screening to Improve Safety of Blood Transfusion

Research paper thumbnail of Hemodynamic measurements for evaluating vasovagal syncope in the emergency department

Clinical and Experimental Emergency Medicine, 2015

Research paper thumbnail of Abdominal thrusts are not recommended for infants with foreign body airway obstruction

Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine, 2009

Research paper thumbnail of Prospective validation of Thrombolysis in Myocardial Infarction and front door Thrombolysis in Myocardial Infarction risk scores in Chinese patients presenting to the ED with chest pain

The American journal of emergency medicine, 2014

Chest pain is a common complaint among emergency department (ED) patients. The Thrombolysis in My... more Chest pain is a common complaint among emergency department (ED) patients. The Thrombolysis in Myocardial Infarction (TIMI) and front door TIMI (FDTIMI) scores are used to risk stratify chest pain patients in many Western countries; they have not been validated in patients with undifferentiated chest pain in Asia. Our objective was to establish the relationship between the TIMI and FDTIMI scores and the 30 day rate of major adverse cardiac outcomes (MACE) in Chinese patients presenting to the ED with chest pain. Prospective, single-center, observational cohort study of consecutive patients presenting with chest pain from July 2009 until March 2010 to a Hong Kong university hospital ED. Data collected included patient characteristics, TIMI items and past medical and medication history. Primary outcome was MACE within 30 days of presentation. MACE was a composite outcome of any of the following: death (all causes), readmission with myocardial infarction, acute coronary syndrome not di...

Research paper thumbnail of Cost-effectiveness of Dermabond versus sutures for lacerated wound closure: a randomised controlled trial

Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine, 2011

Research paper thumbnail of Emergency department intervention for high-risk elders: identification strategy and randomised controlled trial to reduce hospitalisation and institutionalisation

Hong Kong medical journal = Xianggang yi xue za zhi / Hong Kong Academy of Medicine, 2011

Research paper thumbnail of Ethics and analgesia

Emergency medicine journal : EMJ, 2009

The user has requested enhancement of the downloaded file.

Research paper thumbnail of Circulating nucleic acid analysis: diagnostic applications for acute pathologies

Acta neurochirurgica. Supplement, 2005

Much research interest has been shown in recent years for the development of molecular diagnostic... more Much research interest has been shown in recent years for the development of molecular diagnostic strategies based on the analysis of DNA/RNA molecules that are present in the plasma/serum of human subjects. Reported applications include the diagnosis, prognostication or monitoring of malignancies and pregnancy-associated complications. While researchers have speculated that cell death is a potential mechanism that leads to the release of DNA/RNA into the circulation, studies have demonstrated that indeed increased amounts of plasma DNA and RNA could be detected in patients sustaining acute traumatic injuries. The degree of plasma DNA elevation correlated with the severity of injury. Similarly, plasma DNA concentrations have been shown to correlate with indices of prognostic significance in patients with acute stroke. It is expected that new diagnostic markers based on plasma RNA detection could be developed for the evaluation of acute pathologies.

Research paper thumbnail of Evaluation of the Recognition of Stroke in the Emergency Room (ROSIER) Scale in Chinese Patients in Hong Kong

PLoS ONE, 2014

Background and Purpose: The objective of this study was to determine the performance of the Recog... more Background and Purpose: The objective of this study was to determine the performance of the Recognition Of Stroke In the Emergency Room (ROSIER) scale in risk-stratifying Chinese patients with suspected stroke in Hong Kong.

Research paper thumbnail of Optical Properties of Ag and Au Nanoparticles Dispersed within the Pores of Monolithic Mesoporous Silica

The optical absorption of silver and gold nanoparticles dispersed within the pores of monolithic ... more The optical absorption of silver and gold nanoparticles dispersed within the pores of monolithic mesoporous silica upon annealing at elevated temperatures has been investigated. With decreasing particle size, the surface plasmon resonance position of the particles blue-shifts first and then red-shifts for silver/silica samples, but only red-shifts for gold/silica samples. This size evolution of the resonance position is completely different from that previously reported for fully embedded particles. We assume a local porosity at the particle/matrix interface, such that free surface of particles within the pores may be in contact with ambient air, and present a two-layer core/shell model to calculate the optical properties. These calculations also consider deviations from the optical constants of bulk matter to account for corresponding effects below about 10 nm particle size. From the good agreement between experimental results and model calculations, we conclude a peculiar particle/ambience interaction dominating the size evolution of the resonance. Because of the difference of core electron structure, the relative importance of the effects of local porosity and free surface, respectively, are different for silver and gold. For silver, the effect of the local porosity is stronger, but for gold the opposite is found.

Research paper thumbnail of Presence of filterable and nonfilterable mRNA in the plasma of cancer patients and healthy individuals

Clinical chemistry, 2002

As RNA is labile, we investigated whether circulating RNA in human plasma may be present in a par... more As RNA is labile, we investigated whether circulating RNA in human plasma may be present in a particle-associated form. Blood was collected from 27 healthy individuals and 16 hepatocellular carcinoma (HCC) patients. The plasma from each individual was processed by two means: filtration through filters with different pore sizes (from 5 microm to 0.22 microm) and ultracentrifugation. We assessed plasma RNA content by a real-time quantitative reverse transcription-PCR assay for glyceraldehyde-3-phosphate dehydrogenase (GAPDH) transcripts and plasma DNA by a real-time quantitative PCR assay for the beta-globin gene. The plasma GAPDH mRNA concentrations in the healthy individuals were significantly different in every pair of these filter sizes (P <0.05 for each pair). Overall, the plasma GAPDH mRNA concentration was higher by a median of 15-fold (interquartile range, 10- to 24-fold) in the paired unfiltered sample than in the sample filtered through a 0.22 microm filter. In contrast, ...

Research paper thumbnail of A Comparison of Functional Outcome in Patients Sustaining Major Trauma: A Multicentre, Prospective, International Study

PLoS ONE, 2014

Objectives: To compare 6 month and 12 month health status and functional outcomes between regiona... more Objectives: To compare 6 month and 12 month health status and functional outcomes between regional major trauma registries in Hong Kong and Victoria, Australia.

Research paper thumbnail of Age-specific non-invasive transcutaneous Doppler ultrasound derived haemodynamic reference ranges in elderly Chinese adults

Research paper thumbnail of Analysis of trends in emergency department attendances, hospital admissions and medical staffing in a Hong Kong university hospital: 5-year study

International journal of emergency medicine, Jan 8, 2009

The workload of emergency departments (ED) continually changes in response to presentations, over... more The workload of emergency departments (ED) continually changes in response to presentations, overcrowding and availability of expertise and investigations. To investigate changes in ED presentations and care processes, and the relationship of patient demand and ED staff resources to waiting times and processing times. Retrospective analysis of prospectively collected administrative data from January 1999 to April 2005 in an emergency department in a university teaching hospital in Hong Kong. All patients attending the emergency department during the study period were included. Monthly attendance data were retrieved and analysed to determine both qualitative and quantitative changes in the patterns of presentation to the ED using prospectively gathered data. Total ED attendances decreased by 25% during the study with little seasonal variation. The admission rate and the use of ambulances increased steadily and significantly. Medical patients are increasing proportionately, but trauma...

Research paper thumbnail of Evidence-based point-of-care diagnostics: Current status and emerging technologies

Point-of-care (POC) diagnostics brings tests nearer to the site of patient care. The turnaround t... more Point-of-care (POC) diagnostics brings tests nearer to the site of patient care. The turnaround time is short, and minimal manual interference enables quick clinical management decisions. Growth in POC diagnostics is being continuously fueled by the global burden of cardiovascular and infectious diseases. Early diagnosis and rapid initiation of treatment are crucial in the management of such patients. This review provides the rationale for the use of POC tests in acute coronary syndrome, heart failure, human immunodeficiency virus, and tuberculosis. We also consider emerging technologies that are based on advanced nanomaterials and microfluidics, improved assay sensitivity, miniaturization in device design, reduced costs, and high-throughput multiplex detection, all of which may shape the future development of POC diagnostics.

Research paper thumbnail of Leukocyte L-selectin is up-regulated after mechanical trauma in adults

Journal of Trauma-Injury Infection and Critical Care, 1998

Infection and multiple organ failure remain the principal causes of late mortality after trauma d... more Infection and multiple organ failure remain the principal causes of late mortality after trauma despite advances in the resuscitation of injured patients. Because a better understanding of postinjury leukocyte trafficking is essential to the development of possible therapeutic measures aimed at preventing these complications, we have performed a study of one factor in the early posttrauma endothelial adhesion behavior of monocytes, lymphocytes, and neutrophils: their cell surface expression of L-selectin (CD62L). We have also studied the plasma levels of soluble L-selectin in these patients. Two venous blood samples were taken from each of 41 trauma patients at median times of 1 and 20 hours after injury. The study group included 16 patients with major (Injury Severity Score (ISS) &gt; or = 16), 17 with moderate (ISS = 9-15), and 8 with minor (ISS &lt; 9) trauma. Cell surface L-selectin was measured on leukocyte subsets by staining with specific fluorescent-labeled monoclonal antibodies to CD62L and using flow cytometry. Both the percentage of cells expressing the molecule and the mean channel fluorescence were measured. Levels of soluble L-selectin were measured in the plasma, sampled concurrently, by enzyme-linked immunosorbent assay. Monocytes, lymphocytes, and neutrophils all showed an early increase in cell surface L-selectin expression as measured by mean channel fluorescence (p &lt; 0.0001, p &lt; 0.001, and p &lt; 0.0001, respectively), and this persisted in later samples taken at a median 20 hours after injury (p &lt; 0.0001,p &lt; 0.0001, and p &lt; 0.01). Only monocytes showed an increased percentage of cells expressing the molecule in the early phase (p &lt; 0.02), and this remained in the later phase (p &lt; 0.001). Monocytes also showed a further significant increase in mean channel fluorescence (p &lt; 0.02) between the two periods. No significant changes in levels of plasma soluble L-selectin were found at either stage. An increase in the expression of L-selectin on each of three leukocyte populations has been demonstrated in the early phase after trauma. This would tend to promote rolling behavior of leukocytes and increase their contact with the vascular endothelium. There were marked differences in the later responses of the three populations, which may represent differential control of their behavior.

Research paper thumbnail of Adrenaline upregulates monocyte L-selectin in vitro

Resuscitation, 1999

Although surface adhesion molecules mediate leucocyte-endothelial interactions at sites of inflam... more Although surface adhesion molecules mediate leucocyte-endothelial interactions at sites of inflammation, relatively little is known of the factors which increase the expression of L-selectin in circulating leucocytes. The expression of leucocyte L-selectin increases during acute stress events such as injury and is temporally related to an early neuroendocrine response. This study investigates whether adrenaline increases the expression of L-selectin on monocytes, neutrophils and lymphocytes in vitro and whether these effects are mediated via beta-adrenoceptors. A total of 20 ml of blood was withdrawn from 28 healthy volunteers (21 males) with a mean age of 29 years (range 23-67 years). Adrenaline at physiological doses mimicking trauma (0-200 nmol/l) was added to whole blood prior to immunofluorescent staining and analysis by flow cytometry. Propranolol (50 microl of 2 x 10(-5) M) was also added to separate tubes prior to incubation with adrenaline. Saline (40 microl 0.9% solution) was used as a control. Expression is described firstly as percentage of cells expressing L-selectin and secondly as average intensity (mean channel fluorescence, mcf) per cell expressing CD62L. Summary measures were used to analyse the data. A significant increase in both the percentage of monocytes expressing L-selectin and mean channel fluorescence of L-selectin was evident with adrenaline in vitro (P &amp;amp;lt; 0.0001). Maximal increases occurred at 100 nmol/l adrenaline when a 9% increase in the percentage of monocytes expressing L-selectin and a 23% increase in mean channel fluorescence were observed. These effects were both blocked by propranolol (P &amp;amp;lt; 0.0001). No significant differences were observed for neutrophils or lymphocytes except for a slight increase in the percent neutrophils expressing L-selectin, and a small decreasing trend in percent lymphocytes expressing L-selectin. Adrenaline upregulates the surface expression of L-selectin on monocytes in vitro, an effect which is partially mediated by beta-adrenoceptors. As monocytes initiate early aspects of the inflammatory response, these findings suggest that beta-blockade may have an inhibitory role for certain aspects of leucocyte trafficking.