During the past decades, numerous computational fluid dynamics (CFD) studies, constructed from CT or MRI images, have simulated human nasal models. As compared to rhinomanometry and acoustic rhinometry, which provide quantitative information only of nasal airflow, resistance, and cross sectional areas, CFD enables additional measurements of airflow passing through the nasal cavity that help visualize the physiologic impact of alterations in intranasal structures. Therefore, it becomes possible to quantitatively measure, and visually appreciate, the airflow pattern (laminar or turbulent), velocity, pressure, wall shear stress, particle deposition, and temperature changes at different flow rates, in different parts of the nasal cavity. The effects of both existing anatomical factors, as well as post-operative changes, can be assessed. With recent improvements in CFD technology and computing power, there is a promising future for CFD to become a useful tool in planning, predicting, and evaluating outcomes of nasal surgery. This review discusses the possibilities and potential impacts, as well as technical limitations, of using CFD simulation to better understand nasal airflow physiology.
Humans ; Hydrodynamics ; Nasal Cavity ; Nasal Surgical Procedures ; Nose ; Rhinomanometry ; Rhinometry, Acoustic

INTRODUCTIONUntil recently, vancomycin-resistant enterococcus (VRE) infection or colonisation was a rare occurrence in Singapore. The first major VRE outbreak involving a 1500-bed tertiary care institution in March 2005 presented major challenges in infection control and came at high costs. This study evaluates the predictors of VRE carriage based on patients' clinical and demographic profiles.

MATERIALS AND METHODSStudy patients were selected from the hospital inpatient census population during the VRE outbreak (aged 16 years or more). Clinical information from 84 cases and 377 controls were analysed.

RESULTSSignificant predictors of VRE carriage included: age>65 years Odds ratio (OR), 1.98; 95% CI (confidence interval), 1.14 to 3.43); female gender (OR, 2.15; 95% CI, 1.27 to 3.65); history of diabetes mellitus (OR, 1.94; 95% CI, 1.14 to 3.30), and staying in a crowded communal ward (OR, 2.75; 95% CI, 1.60 to 4.74). Each additional day of recent hospital stay also posed increased risk (OR, 1.03; 95% CI, 1.01 to 1.04).

CONCLUSIONElderly diabetic females with prolonged hospitalisation in crowded communal wards formed the profile that significantly predicted VRE carriage in this major hospital-wide outbreak of VRE in Singapore. It is imperative that active VRE surveillance and appropriate infection control measures be maintained in these wards to prevent future VRE outbreaks.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Case-Control Studies ; Cross Infection ; drug therapy ; epidemiology ; microbiology ; Disease Outbreaks ; Enterococcus ; drug effects ; Enterococcus faecalis ; isolation & purification ; Enterococcus faecium ; isolation & purification ; Female ; Humans ; Infection Control ; Male ; Medical Audit ; Middle Aged ; Risk Factors ; Singapore ; epidemiology ; Streptococcal Infections ; drug therapy ; epidemiology ; Vancomycin ; pharmacology ; therapeutic use ; Vancomycin Resistance

INTRODUCTIONWith the potential threat of an avian influenza (AI) pandemic, healthcare workers (HCWs) are expected to play important roles, and they encounter significant stress levels from an expected increase in workload. We compared the concerns, perceived impact and preparedness for an AI pandemic between HCWs working in public primary care clinics and a tertiary healthcare setting.

MATERIALS AND METHODSAn anonymous, self-administered questionnaire was given to 2459 HCWs working at 18 public polyclinics (PCs) and a tertiary hospital (TH) in Singapore from March to June 2006. The questionnaire assessed work-related and non-work-related concerns, perceived impact on personal life and work as well as workplace preparedness.

RESULTSWe obtained responses from 986 PC and 873 TH HCWs (response rate: 74.6% and 76.7%). The majority in both groups were concerned about the high AI risk from their occupation (82.7%) and falling ill with AI (75.9%). 71.9% accepted the risk but 25.5% felt that they should not be looking after AI patients with 15.0% consider resigning. HCWs also felt that people would avoid them (63.5%) and their families (54.1%) during a pandemic. The majority expected an increased workload and to feel more stressed at work. For preparedness, 74.2% felt personally prepared and 83.7% felt that their workplaces were prepared for an outbreak. TH HCWs were more likely to be involved in infection-control activities but the perception of infection-control preparedness in both groups was high (>80.0%).

CONCLUSIONSHCWs in both public primary and tertiary healthcare settings felt prepared, personally and in their workplaces, for a pandemic. Their main concerns were risks of falling ill from exposure and the possibility of social ostracism of themselves and their families. Preparedness levels appeared high in the majority of HCWs. However, concerns of HCWs could affect their overall effectiveness in a pandemic and should be addressed by incorporating strategies to manage them in pandemic planning.

Adolescent ; Adult ; Aged ; Animals ; Attitude of Health Personnel ; Birds ; Disaster Planning ; Disease Outbreaks ; Female ; Humans ; Infectious Disease Transmission, Patient-to-Professional ; prevention & control ; Influenza A Virus, H5N1 Subtype ; pathogenicity ; Influenza in Birds ; transmission ; Influenza, Human ; epidemiology ; prevention & control ; transmission ; virology ; Male ; Middle Aged ; Primary Health Care ; Singapore