MYTHS ABOUT WOUND IRRIGATION & HOW TO IMPROVE YOUR PRACTICE
PATRICK O’MALLEY, MD
Irrigation of wounds is probably the most important thing we can do to prevent infection, so we must have a good understanding of this often overlooked and underappreciated component of laceration management. There are three components to consider – water type, volume, and pressure. Let’s look at all these components and some associated misbeliefs.
“The solution to pollution is dilution!” Water is the key here-and lots of it! Interestingly, the type of water is less important than one may think. It is perfectly fine to use sterile water or saline, but you don’t HAVE to. Potable water, yes; water from the tap is just as safe and effective in reducing the risk of infection in a laceration repair. Numerous studies have shown us that we can safely use tap water for wound irrigation. (1,2,3) As an added benefit, this may lead to a small cost savings. A liter of saline may be several dollars per bottle.
Next is the VOLUME of water needed for irrigation. Many sources recommend using 50-100ml of water per centimeter of laceration. (4) A 5 cm laceration therefore should be irrigated with 250-500 ml of water! Using a syringe and splash guard is the most common method to achieve this. If the location of the wound is amenable, you can also place the laceration directly under the tap and let the water run over it for a few minutes. Probably not feasible for grandma’s scalp laceration, but a large number of lacerations can be irrigated this way. This allows for a copious amount of water to come into contact with the wound, remove gross contamination, and bacteria. This will greatly exceed the 50-100 ml/cm guideline and reduce the risk of infection even further.
Lastly is pressure. Sources as far back as the 1970’s recommend anywhere from 8-15 psi at the wound surface to properly irrigate a traumatic skin injury. (4) The goal here is to overcome the adhesive forces of bacteria and biofilm formation that accumulates shortly after a wound occurs. These studies used a 19-gauge needle and 35 cc syringe, both products I have never seen before. It is accepted that moderate pressure onto the plunger of a 20 cc syringe, combined with a splash guard, is enough to generate pressure within the 12-15 psi range. Even though every sink tap is different, it is accepted that the pressure generated by a common tap in a hospital or clinic room is enough to achieve this goal. What is NOT acceptable is using a bulb syringe or a plain syringe without a splash guard or punching holes in the cap of a saline bottle and squeezing it. These do NOT generate enough pressure and are practices that should be abandoned.
Paying closer attention to these elements of wound irrigation will give your patients a better chance at healing better without infection!