Bystander resuscitation attempts at heroin overdose: does it improve outcomes?

Study objective: To document the characteristics and effectiveness of cardiopulmonary resuscitation (CPR) at non-fatal heroin overdose events in Melbourne, Australia. Methods: A retrospective analysis of a computerised database of ambulance attendance records at non-fatal heroin overdose cases for the period 1/12/1998 to 31/7/2000 was undertaken.

Main outcome measures: The main outcome measure was the rate of patient hospitalisation. The rate of CPR administration at heroin overdose cases was also examined, along with characteristics of the attendance, such as the age and sex of the overdose case, the relationship of person providing CPR to the overdose case as well as the location, time and date of the event.

Results: CPR was administered prior to ambulance arrival in 579 heroin overdose cases (9.4% of total heroin overdose cases attended) between 1/12/98 and 31/7/2000. A greater proportion of female overdose cases were administered CPR than males and CPR administrations were evenly distributed across attendances occurring in private and public locations. Bystander administration of CPR prior to ambulance attendance resulted in a significantly lower rate of heroin user hospitalisation (14.5%) compared to cases where bystander CPR was not administered (18.8%).

Conclusions: While CPR administration prior to ambulance attendance at heroin overdose events is relatively uncommon (especially compared to out-of-hospital cardiac arrest), such administration was associated with a statistically significant improvement in clinical outcomes in cases of non-fatal heroin overdose. These findings suggest that the provision of CPR training to people likely to come into contact with heroin overdose events may be an effective strategy at minimising consequent overdose-related harm.

Thermal control of high pressure die casting using computational fluid dynamics

The quality of high pressure die castings is a function of many interdependent parameters. It has been observed that many defects detected in the HPDC castings can be tracked back to poor die temperature distribution in the critical areas. It has therefore been recommended that the development of a technique to directly control the critical features - making them less sensitive to thermal related parameters - be very beneficial to the HPDC industry. From the information obtained from thermal image (processing), computational fluid dynamics has been applied to design the layout of internal cooling system and assign the flow conditions such as flow rate and pressure of the cooling water. it is observed that CFD prediction provides an excellent insight into the thermal balance of the high pressure die casting.

Family member presence during resuscitation in the emergency department: an Australian perspective

Objective: The practice of family member presence during resuscitation in the ED has attracted widespread attention over the last few decades. Despite the recommendations of international organizations, clinical staff remain reluctant to engage in this practice in many EDs. This paper separates the evidence from opinion to determine the current state of knowledge about this practice.

Methods: A search strategy was developed and used to locate research based publications, which were subsequently reviewed for the strength of evidence providing the basis for recommendations.

Results: The literature was examined to reveal what patients and their family members want; the outcomes of family presence during resuscitation for patients and their family members; staff views and practices regarding family presence during resuscitation. Findings suggest that providing the opportunity to be with their critically ill family member is both important to and beneficial for families, however, disparity in staff views has been identified as a major obstacle to family presence during resuscitation. Examination of published guidelines and staff practices described in the literature revealed consistent elements.

Conclusion: Although critics point to the lack of rigour in this body of literature, the current state of knowledge suggests merit in pursuing future research to examine and measure effects of family member presence during resuscitation on patients, family members and healthcare providers.

Effect of surface roughness of Ti, Zr, and TiZr on apatite precipitation from simulated body fluid

Some of the critical properties for a successful orthopedic or dental implant material are its biocompatibility and bioactivity. Pure titanium (Ti) and zirconium (Zr) are widely accepted as biocompatible metals, due to their non-toxicity. While the bioactivity of Ti and some Ti alloys has been extensively investigated, there is still insufficient data for Zr and titanium-zirconium (TiZr) alloys. In the present study, the bioactivity, that is, the apatite forming ability on the alkali and heat treated surfaces of Ti, Zr, and TiZr alloy in simulated body fluid (SBF), was studied. In particular, the effect of the surface roughness characteristics on the bioactivity was evaluated for the first time. The results indicate that the pretreated Ti, Zr and TiZr alloy could form apatite coating on their surfaces. It should be noted that the surface roughness also critically affected the bioactivity of these pretreated metallic samples. A surface morphology with an average roughness of approximately 0.6 microm led to the fastest apatite formation on the metal surfaces. This apatite layer on the metal surface is expected to bond to the surrounding bones directly after implantation.

Characterization of high fluid strain micro contractions to study the stress on biological fluids

Microfluidics has the potential to enhance the understanding of the biological fluids under strain, due to the laminar nature of the fluid and the possibility to mimic the real conditions. We present advances on charaterization of a microfluidic platform to study high strain rate flows in the transport of biological fluids. These advances are improvements on the reproduction of a  constant extensional strain rate using micro contractions and development of 3D numerical models. The micro geometries have been fabricated in polydimethyl siloxame (PDMS) using standard soft-lithography techniques with a photolithographically patterned mold. A comparison of some microcontractions with different funnel characteristics is presented. The Micro Particle Image Velocimetry technique has been applied to validate the numerical simulations. We demonstrate the use of microfluidics in the reproduction of a large range of controllable extensional strains that can be used in the study of the effect of flow on biological fluids.