Wound cleansing and irrigation
The following is from information in reference (1) in References:
- Through wound cleansing and irrigation are the most important steps in repairing wounds and lacerations.
- Povidone iodine solution (not scrub preparation) is the most effective skin, or periphery, cleanser. [However, the 10% povidone iodine solution is still too concentrated to be used. Please see the information on how to prepare a 1% povidone iodine solution for wound cleansing below.]
- Either water or saline can be used as a wound irrigation to flush debris and bacteria from inside a laceration.[See wound irrigation below for details and caveats.]
- Don’t use hydrogen peroxide for wound care.
- Shaving hair over wounds can lead to dermal injuries and an increased infection rate. It can be cleaned of the same as skin and left alone, clip with scissors, or flattened away from the wound with lubricants.
- Never Shave an eyebrow. It can grow back abnormally or not at all.
- Wound care exposes the caregiver [and others in the room] to pathogens such as human immunodeficiency virus (HIV) and hepatitis B and C. Blood and body fluid precautions should be observed. [These precautions, which need to be in place for everyone in the room, should include eye protection and a mask.]
- Anesthesia should proceed wound preparation to minimize the pain of a thorough cleansing and irrigation. [see Anesthesia below]
- [Determine the presence or absence of foreign material in the wound. This is critical. See foreign material below.]
Povidone iodine for wound cleansing:
Povidone iodine comes as a 10% solution and as an anionic detergent scrub (povidone iodine scrub preparations). Excessive exposure of open wounds to the scrub solution by wounds scrubbing or soaking is not recommended. Scrub solutions were designed for preoperative preparation of intact skin before operative incisions. So do not use the the scrub solution for lacerations.
Povidone iodine, without the detergent, is distributed most commonly is a 10% solution. When diluted to 1% concentration or lower, it can be applied safely to wounds, and it retains its bacterial activity. It has no inherent negative effects on wound healing. Adverse and allergic reactions are extremely rare, even when the solution is used in known iodine allergic patients.
Wound periphery cleansing:
The main purpose for periphery wound cleansing or “scrubbing” is removal of any visible contamination and dried blood. Periphery cleansing alone is insufficient for wound preparation without accompanying irrigation. The endpoint of skin cleansing is when the area surrounding the wound or laceration is visibly clean. There is no fixed scrubbing time. If the skin itself cannot be cleansed of all particulates, the risk for “tattooing” increases.
Scrubbing within the wound itself is controversial [but often necessary. See reference one, pages 77 and 78 for details. ]
Wound irrigation is the most effective way to remove debris and contaminants from within a laceration. Irrigation also is the most effective method of reducing bacterial counts on wound surfaces. In comparing methods of irrigation for highly contaminated wounds, high-pressure streams (5 to 70 PSI) of saline are clearly superior to low-pressure streams, such as those that might be obtained with a bulb type syringe (0.521 PSI). Current practice is based on work done with a 35 mL syringe attached to a 19 gauge catheter. This system develops 7 to 8 PSI and is effective in reducing debris and bacterial contamination from the types of wounds and lacerations managed by emergency caregivers. Pulsatile lavage, which develops a PSI of 50 to 70, is effective in lowering bacterial counts and wound infection rates. [But] Significant amounts of irrigation fluid can dissect well beyond the wound margins, however pulsatile lavage systems are suited for larger, heavily contaminated ones best managed by surgical specialists in the operating room.
Traditionally, saline is been used as the solution of choice. It is sterile and compatible with body tissues. More recently, saline’s primacy as the best fluid for this task has been challenged. For example, in a large prospective trial of 530 pediatric patients comparing saline with running tap water, there was no difference in wound infection rates between groups (2.8% versus 2.9%). These were simple wounds with low levels of contamination.
After periphery cleansing, the wound is irrigated with the syringe and splash shield. Periphery cleansing in irrigation can be alternated until there are no visible skin nor wound contaminants. The amount of irrigation fluid can vary from 100 to 250 mL or more, depending on the level of contamination of the wound. The 35 mL syringe and splash shield are held close to the wound so that the force of the stream is not dissipated by distance. Whatever cannot be irrigated out of the wound is removed by mechanicals scrubbing with a sponge or with sharp debridement.
If visible contamination remains despite thorough cleansing and irrigation, sharp debridement is performed with tissue scissors or a surgical scalpel with a number 15 blade. Ultimately, other strategies, such as wound excision might be necessary to handle ones that cannot be managed with these steps. Strategies for the difficult wound are discussed in another post and that post is based on Chapter 9 of the reference.
Cleansing is complete and a wound is ready to close when, literally, the wound looks clean to the eye. There should be no visible contaminants, and the tissue should appear to be pink and viable. Usually there is slight fresh bleeding. A sterile sponge can be laid over the wound until the operator is ready to proceed with repair.
Because wound cleansing can be uncomfortable if not outright painful, most wounds should be anesthetized before cleaning. Not only is the patient more comfortable, but also the cleansing can be more vigorous and effective. Techniques for administering anesthetics are discussed fully in Chapter 6.
An issue that often arises concerning the administration of anesthetics before wound cleansing is whether the bacteria can be embedded further into a wound if the needle is passed through a contaminated surface. There’s no clear scientific evidence that needles can spread bacteria beyond the wound margins. In clean, sharp ones, this issue is of no concern, and direct wound infiltration can be performed safely. For wounds that are visibly in heavily contaminated. The parallel injection technique or an appropriate nerve block can be used if necessary to avoid this hypothetical complication.
As part of wound preparation, it is important to determine the presence or absence of foreign bodies in the wound. Foreign bodies of all types should be considered harmful with the potential for causing infection if left in the tissues. In addition, retained foreign objects are among the most common reasons for malpractice suits wrought against emergency physicians. Although where irrigation removes most debris, direct visualization and removal by instruments often are required. An alert patient can report the “sensation” of a foreign body still in the wound. Radiographs are particularly useful to find tooth fragments, metallic objects, and glass. It is a popular misconception that glass cannot be visualized by radiographs; 90% of all glass (0.5 mm or larger) can be detected by radiographs. The removal of foreign bodies is discussed in more detail in Chapter 16.
Wounds and Lacerations: Emergency Care and Closure, Fourth Edition, 2012.
Ma and Mateer’s Emergency Ultrasound, Third Edition, 2014.