Basic science investigations into clinically relevant orthopaedic conditions are very common—and often very fruitful. What’s not very common is seeing results from large, multicenter randomized trials published in the same time frame as high-quality in vivo basic-science research on the same clinical topic.
But the uncommon has occurred. In the November 1, 2017 issue of The Journal, Chiaramonti et al. present research on the effects of 20-psi pulsatile lavage versus 1-psi bulb-syringe irrigation on soft tissue in a rat model of blast injuries. With support from the US Department of Defense, Chiaramonti et al. developed an elegant animal study that found radiological and histological evidence that lavage under pressure—previously thought to be critical to removing contamination in high-energy open fractures—results in muscle necrosis and wound complications.
Although none of the rats developed heterotopic ossification during the 6-month study period, the authors plausibly suggest that the muscle injury and dystrophic calcification they revealed “may potentiate the formation of heterotopic ossification by creating a favorable local environment.” Heterotopic ossification is an unfortunately common sequela in patients who suffer blast-related limb amputations.
The aforementioned rare alignment between basic-research findings and clinical findings in people relates to a large multicenter randomized clinical trial recently published in The New England Journal of Medicine. That study found that one-year reoperation rates among nearly 2,500 patients treated surgically for open-fracture wounds were similar whether high, low, or very low irrigation pressures were used. This is a case where the clinical advice from basic-study authors Chiaramonti et al. to keep “delivery device irrigation pressure below the 15 to 20-psi range” when managing open fractures is based on very solid ground.
Marc Swiontkowski, MD
Irrigation and debridement of open fractures have been standard practices since the late 1800s. However, the finer details have not been agreed upon. For example, should we use higher pressures with pulsatile lavage devices? And will adding soap to standard saline irrigation solution get better results? Answers to those two questions from lab and animal studies over the years have been limited and contradictory. The goal of the recently reported FLOW study (Fluid Lavage of Open Wounds) was to answer those questions definitively.
Initially, a pilot study with just over 100 patients suggested that using soap might yield fewer adverse events requiring a return to the OR. Little difference was noted between high and low pressures using a pulsatile lavage device. Most importantly, the pilot showed that a definitive study was feasible.
FLOW investigators, of which I was one, then began pursuing a multicenter, international, randomized, controlled study to evaluate the effects of irrigation pressure and solutions on open fractures. The US Department of Defense (DoD), the Canadian Institutes of Health Research, and others supported us in the definitive trial. From what we learned in the pilot study and from DoD input, we added a third arm to the pressure investigation and included gravity flow, which is essentially a bag of fluid run through quarter-inch tubing into the wound.
We collected data for five years from 2,447 patients at 41 sites worldwide and achieved a 90% 12-month follow-up. The results demonstrated that reoperation rates for the three different pressures were similar. But unlike the size-limited data from the pilot study, using soap in the irrigation solution resulted in a significantly higher reoperation rate than normal saline.
This second finding should convince us that saline is the irrigation solution of choice and that by avoiding soap, adverse outcomes can be diminished and costs lowered for institutions. The discrepancy between the soap findings in the pilot data and the full study may simply reflect the need for larger numbers. Intuitively, we might think that soap, which we use all the time for hand-washing, would be better because it helps remove debris and bacteria. However, the FLOW findings suggest that soap may have a negative impact on soft tissues and bone, making reoperation rates significantly higher. In regard to pressures, the use of a pulsatile lavage with high or low pressures offered no apparent benefit compared to irrigation with gravity flow. This should allow sites to avoid the cost of using pulsatile lavage devices.
Taken together, these findings should reassure institutions worldwide that do not have access to soap or pulsatile lavage devices that their wound-irrigation practices are not compromised and may indeed be the standard of care based on the FLOW data.
Kyle Jeray, MD
Greenville Health System
Vice-Chairman of Academics, Department of Orthopaedic Surgery
JBJS Associate Editor