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Dominic Lee

Publications and source records attributed to Dominic Lee.

6 recordsLinked to original sources
PubMed2006

Parameter identification and sedative sensitivity analysis of an agitation-sedation model.

Sedation administration and agitation management are fundamental activities in any intensive care unit. A lack of objective measures of agitation and sedation, as well as poor understanding of the underlying dynamics, contribute to inefficient outcomes and expensive healthcare. Recent models of agitation-sedation dynamics have enhanced understanding of the underlying dynamics and enable development of advanced protocols for semi-automated sedation administration. In this research, the agitation-sedation model parameters are identified using an integral-based fitting method developed in this work. Parameter variance is then analysed over 37 intensive care unit patients. The parameter identification method is shown to be effective and computationally inexpensive, making it suited to real-time clinical control applications. Sedative sensitivity, an important model parameter, is found to be both patient-specific and time-varying. However, while the variation between patients is observed to be as large as a factor 10, the observed variation in time is smaller, and varies slowly over a period of days rather than hours. The high fitted model performance across all patients show that the agitation-sedation model presented captures the fundamental dynamics of the agitation-sedation system. Overall, these results provide additional insight into the system and clinical dynamics of sedation management.

Computer Simulation↗
PubMed2006

Comparative stigma of HIV/AIDS, SARS, and tuberculosis in Hong Kong.

This study compares public stigma towards three types of infectious diseases- human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), severe acute respiratory syndrome (SARS), and tuberculosis (TB)-tests an attribution model of stigma, and explores the relationships between stigma and public attitudes towards government policies in Hong Kong. Using a population-based telephone survey, 3011 Hong Kong Chinese adults were randomly assigned to one of the three disease conditions and were interviewed about their attitudes and beliefs towards the assigned disease. Findings showed that public stigma was the highest towards HIV/AIDS, followed by TB and SARS. Using multi-sample model structural equation modeling, we found that the attributions of controllability, personal responsibility, and blame were applicable in explaining stigma across three disease types. Knowledge about the disease had no significant effect on stigma. Participants with less stigmatizing views had significantly more favorable attitudes towards government policies related to the diseases. The study is an important attempt in understanding the attributional mechanisms of stigma towards infectious diseases. Implications for stigma reduction and promotion of public awareness and disease prevention are discussed.

Acquired Immunodeficiency Syndrome↗
PubMed2004

Modeling and control of the agitation-sedation cycle for critical care patients.

Agitation-sedation cycling in critically ill patients, characterized by oscillations between states of agitation and over-sedation, is damaging to patient health, and increases length of stay and healthcare costs. The mathematical model presented captures the essential dynamics of the agitation-sedation system for the first time, and is statistically validated using recorded infusion data for 37 patients. Constant patient-specific patient parameters are used, illustrating the commonality of these fundamental dynamics over a broad range of patients. The validated model serves as a basis for comparison of sedation administration methods, devices, therapeutics and protocols. Heavy derivative feedback control is shown to be an effective means of managing agitation, given consistent agitation measurement. The improved agitation management reduces the modeled mean and peak agitation levels 68.4% and 52.9% on average, respectively. Some patients showed over 90% reduction in mean agitation level through increased control gains. This improved agitation management is achieved via heavy derivative feedback control of sedation administration, which provides an essentially bolus-driven management approach, aligned with recent sedation practices.

Computer Simulation↗
PubMed2003

Suprapubic stab cystostomy: a safer technique.

Suprapubic catheters have gained wide acceptance in urology. Although many regard their insertion a simple procedure, morbidity is significant and is probably underreported. We describe a percutaneous technique using intraoperative ultrasonography combined with flexible cystoscopy to ensure safe insertion, minimizing the risk to adjacent viscera.

Cystoscopy↗
PubMed2002

A qualitative study of the experiences of a group of Hong Kong Chinese women diagnosed with postnatal depression.

AIM OF THE STUDY: To examine the lived experiences of a group of Hong Kong Chinese women diagnosed with postnatal depression. BACKGROUND: Postnatal depression affects approximately 1 in 10 childbearing women in Hong Kong. However, most studies of postnatal depression have been carried out in Western societies and no qualitative research was found describing the experience of Hong Kong Chinese mothers with postnatal depression. DESIGN: A phenomenological study was conducted. Data were collected by semi-structured interviews. A purposive sample of 35 women diagnosed with postnatal depression was interviewed. Interview data were analysed following Colaizzi's phenomenological methodology. RESULTS: Themes that emerged describing participants' experiences included trapped in the situation, ambivalent towards the baby, uncaring husband, and controlling and powerful in-laws. Women felt hopelessness, helplessness and loss of control. They were trapped in a situation that had no way of escape except by violent means, such as homicide or suicide. Feelings towards the baby were ambivalent, both hate and love. Several women had injured, or had thought of injuring or killing, their babies and/or themselves. Women's unhappiness was attributed to a noncaring husband, and controlling and powerful in-laws. Generally, women did not seek help until their depression was diagnosed by screening tests. CONCLUSION: This study has revealed insights into how women experienced postnatal depression in Hong Kong, and what they perceived as contributing to their depression. These insights may be used to guide interventions for women and their families to raise awareness regarding the support childbearing women need.

Adaptation, Psychological↗