Broadband diffuse optical spectroscopy measurement of hemoglobin concentration during hypovolemia in rabbits.

Serial blood draws for the assessment of trauma patients' hemoglobin (sHgb) and hematocrit (sHct) is standard practice. A device that would allow for continuous real-time, non-invasive monitoring of hemoglobin and tissue perfusion would potentially improve recognition, monitoring and resuscitation of blood loss. We developed a device utilizing diffuse optical spectroscopy (DOS) technology that simultaneously measures tissue scattering and near-infrared (NIR) absorption to obtain non-invasive measurements of oxy- (Hb-O(2)), deoxyhemoglobin (Hb-R) concentrations and tissue hemoglobin concentration (THC) in an animal model of hypovolemic shock induced by successive blood withdrawals. Intubated New Zealand White rabbits (N = 16) were hemorrhaged via a femoral arterial line every 20 min until a 20% blood loss (10-15 cc kg(-1)) was achieved to attain hypovolemia. A broadband DOS probe placed on the inner thigh was used to measure muscle concentrations of Hb-O(2) and Hb-R, during blood withdrawal. THC and tissue hemoglobin saturation (S(T)O(2)) were calculated from DOS [Hb-O(2)] and [Hb-R]. Broadband DOS-measured values were compared against traditional invasive measurements: systemic sHgb, arterial oxygen saturation (S(a)O(2)) and venous oxygen saturation (S(v)O(2)) drawn from arterial and central venous blood. DOS and traditional invasive measurements versus blood loss were closely correlated (r(2) = 0.96) showing a decline with removal of blood. S(T)O(2) and [Hb-O(2)] followed similar trends with hemorrhage, while [Hb-R] remained relatively constant. These measurements may be limited to some extent by the inability to distinguish between hemoglobin and myoglobin contributions to DOS signals in tissue at this time. Broadband DOS provides a potential platform for reliable non-invasive measurements of tissue oxygenated and deoxygenated hemoglobin and may accurately reflect the degree of systemic hypovolemia and compromised tissue perfusion.

New stressors for GDPs in the past 10 years.

In 1987 Cary Cooper published research in the BDJ identifying factors which caused stress in dentists in general practice. It also identified that stress levels in the dental profession as a whole were high. Ten years later, Cary Cooper and Gerry Humphris have returned to this subject to see what new stressors are affecting GDPs today.

MRI update: a pilot scheme for a multidisciplinary liaisons project.

This MRI update brings you details of two research projects that are currently underway. The first is a project by Mark Bowen researching into multidisciplinary liaisons and whether it can improve patient care. The second is about the influence of quality management on the success of dental practices by David Ward, a GDP working in Sheffield.

MRI update: are you disrupting your practice by failing to value your dental nurse?

It is widely accepted that the practice support staff, and particularly the dental nurse, have a major role to play in ensuring patient satisfaction and reassurance. Despite this, findings from recent research by Maria Mindak show that dental nurses do not as a rule receive praise, encouragement or feedback from their dentist. As a result, morale is low and staff turnover is high. It is all well and good for dentists to shrug their shoulders and accept that this is just how things are, but as leaders of the dental team is it their responsibility to encourage 'job satisfaction.' And as business people is it in their interest to keep staff in whom they have invested training time and resources. Is it time to rethink your people resources strategy?

MRI update: the effect of dentist attire on patient perceptions of skill, caring and professionalism.

We are trained from our earliest years to draw significance from colour and dress. Thus, whilst Cinderella shyly appears in a sparkling white gown, the wicked stepmother flaunts in purple and black; in the same way we come to expect doctors to wear a white coat. But does what doctors and dentists wear really affect patient perceptions of the professionalism of the service and quality of care received? The results of a recent study by Martin Fallowfield, a GDP in Peterborough, will soon uncover the facts. Dentists can then know whether what they wear affects their patients' perceptions of the service they provide.

MRI--the story so far.

On October 20, 1994, the Management Research Initiative was launched. Its aim? To support and publish sound quality research in management specifically related to dental practice so that a body of informed knowledge is available for dentists who want real answers to their questions about what management techniques work in practice. This article brings you up to date on what the MRI has achieved so far.

MRI update.

The Management Research Initiative is successfully attracting interest from the business and management world in a drive to see dentistry recognised as a key area for management research. This issue's MRI update reports on the reception the initiative received at this year's British Academy of Management conference, and how dental practitioners can assess and improve their strategy planning by participating in research to be carried out at the Sheffield Business School.

MRI update.

The Management Research Initiative aims to encourage research in dental practice management. We hope that GDPs and dental teams will get involved either by looking at management issues in their own practice or by collaborating with other researchers. In this update we give details of research being carried out that will give GDPs evidence of what influences a patient's choice of dentist and how the changing role of the dentist as manager is affecting stress levels.