Pulsed lavage in wound cleansing

Abstract

The literature suggests that the amount of pressure used in irrigation is the key variable to achieve effective wound cleansing. Pressures of 1 psi or less have been found to be of little clinical value for wound cleansing. Although surface bacterial counts are reduced by irrigation in general, the literature indicates that higher pressures are more effective. Surface debris, such as loose necrotic tissue and wound exudate, has been shown to be most effectively removed using pressures between 5 and 10 psi. Irrigation pressures above 10 psi protect the wound from gross infections. Inconsistencies in reporting output and impact pressures, described previously, create confusion in performing a meta-analysis of research results. Future research examining the efficacy of pulsed lavage must demonstrate consistency in reporting impact pressures at the tissue's surface. Research comparing the efficacy of continuous or intermittent (pulsed) lavage procedures has produced less clear results. The results of one study suggest that both methods are effective at removing surface bacteria when using pressures of 10 to 15 psi, whereas another study suggests that continuous irrigation is more effective than pulsed irrigation at removing bacteria at 25 psi. Clearly, additional research is needed that compares the effects of pulsed and continuous irrigation at a variety of pressure levels, before suggesting a preferred method. Until there is definitive evidence, it may be advisable to eliminate the use of the phrase 'high-pressure irrigation' when referring to pulsed lavage because 'pulsed lavage' refers only to the application of an intermittent stream of fluid regardless of the pressure level. Research comparing the effectiveness of whirlpool and pulsed lavage on wound cleansing is scant. Two studies suggest that pulsed lavage following whirlpool agitation is more effective at removing bacteria than lavage alone. In a recent study, however, pulsed lavage was found to be more effective than whirlpool in promoting wound healing. Additional clinical studies comparing the effects of pulsed lavage and whirlpool on wound cleansing and healing are needed. Recognizing the progressive financial restrictions facing the clinician, future comparisons should also include cost analyses of the 2 methods. Total costs per incident, number of treatments required to achieve wound closure, and per-treatment costs should be included. Pulsed lavage appears to be a safe method for wound cleansing. Research has demonstrated no evidence of bacteremia following lavage applications, regardless of pressure. Concerns that 'high-pressure' (output pressure of 70 psi) lavage may disseminate contaminants to surrounding tissues appear to be unwarranted, but more research needs to be conducted in order to confidently apply pulsed lavage to all types of wounds at all stages of the healing process. Until more convincing controlled studies are performed, establishing safe levels of irrigation pressure in wound cleansing, Rodeheaver's suggestion needs to be heeded: continue to use the AHCPR guideline of irrigation pressures between 4 and 15 psi.