The flaws of laser Doppler in negative-pressure wound therapy research.

Recent studies, using modalities other than laser Doppler, have indicated that perfusion during negative-pressure wound therapy (NPWT) is reduced, contrary to world literature. The aim of the present study was to evaluate whether the measuring technique of the laser Doppler could be influenced by the compressive nature of NPWT dressings and whether this could explain the conflicting findings. A hypothesis that it may be possible for laser Doppler to record similar readings to those obtained during NPWT by merely compressing tissues manually was tested on 12 NPWT dressings, with each undergoing an alternating series of manual compressive forces and NPWT (-125 mmHg).

The influence manufacturers have on negative-pressure wound therapy research.

Background: Studies investigating the effects of negative-pressure wound therapy using the Chariker-Jeter system (gauze-based interface) and the vacuum-assisted closure system often have outcomes that favor one particular system. This study attempts to examine whether manufacturer involvement could be related to the outcomes of these scientific studies.

Methods: A literature review was undertaken to identify a cohort of studies that compared these two forms of negative-pressure wound therapy.

Does a zone of increased perfusion exist around negative-pressure dressings?

Background: Although recent work has demonstrated that perfusion adjacent to a negative-pressure wound therapy dressing is decreased, laser Doppler studies have indicated that there is a zone of increased perfusion a couple of centimeters away. The existence of such a zone of increased perfusion is counterintuitive to the fact that negative-pressure wound therapy has been shown to increase tissue pressure. This study, using an alternative to laser Doppler, evaluated whether such a zone exists.

Pneumocephalus following gunshot injury to the thoracic vertebral column: a case report.

Subarachnoid pleural fistula (SPF) following injury to the vertebral column is an extremely rare complication and is usually described after blunt trauma. We report the first case of SPF with pneumocephalus due to a gunshot wound to the spine.

Avoiding futile damage control laparotomy.

Background: The age of a patient, lowest pre-operative pH and lowest core temperature are significant predictors of mortality in patients undergoing damage control surgery (DCS). An equation had previously been devised based on these three variables, which could predict which patients would die despite undergoing DCS (100% positive predictive value, 25% sensitivity). The aim of this study was to validate this equation by testing it on a different cohort of patients undergoing DCS.

Negative-pressure wound therapy II: negative-pressure wound therapy and increased perfusion. Just an illusion?

Background: A recent study demonstrated that negative-pressure wound therapy increases underlying tissue pressure. This finding is incongruous with studies using laser Doppler that show that perfusion is immediately increased on initiation of suction. This study investigated perfusion in negative-pressure wound therapy using two alternative modalities.

Negative-pressure wound therapy I: the paradox of negative-pressure wound therapy.

Background: Does negative-pressure wound therapy reduce or increase the pressure of wound tissues? This seemingly obvious question has never been addressed by a study on living tissues. The aim of this study was to evaluate the nature of tissue pressure changes in relation to negative-pressure wound therapy.

Methods: Three negative-pressure wound therapy dressing configurations were evaluated-circumferential, noncircumferential, and those within a cavity-on 15 human wounds, with five wounds in each category.

The paradox of negative pressure wound therapy--in vitro studies.

Negative-pressure wound therapy (NPWT) has revolutionised wound care. Yet, it is still not understood how hypobaric tissue pressure accelerates wound healing. There is very little reported on the relevant physics of any substance subjected to suction in this manner.