Article Citation: Weiss EA, Oldham G, Lin M, Foster T, Quinn JV. Water is a safe and effective alternative to sterile normal saline for wound irrigation prior to suturing: a prospective, double-blind, randomised, controlled clinical trial. BMJ Open. 2013 Jan 16;3(1). PMID: 23325896

 

What we already know about the topic: Traumatic wounds are a frequent complaint seen in the ER. Wound irrigation is an important step in management. Proper irrigation lowers the risk of retained foreign body and infection. There are a number of options for irrigation including tap water, sterile water or saline, and antiseptic solutions.

 

Why this study is important: Sterile normal saline is more expensive and can be less readily available than tap water. Using tap water in lieu of sterile saline in wound irrigation can prevent significant financial waste.

 

Brief overview of the study: This was a randomized, double-blind clinical trial. It compared the use of sterile saline against tap water for wound irrigation in lacerations. The main outcome of interest was the wound infection rate. The study was conducted at the Emergency Department of a tertiary care facility with 55,000 visits annually. Patients with a soft tissue laceration requiring repair were included. Exclusion criteria included age less than 1 year, underlying immunocompromising illnesses, currently being on antibiotics, puncture or bite wounds, underlying tendon or bone involvement, and wounds less than nine hours old. All wounds were anesthetized. 500mL of solution was delivered via a 35 mL syringe equipped with an 18 gauge IV catheter (which produces approximately 8 psi hydraulic pressure). Wounds were checked 2 days later in most cases. Patients were also contacted by telephone 1 month later to assess for delayed infection or other complications. 663 patients were enrolled, of which 32 were later excluded and 6 were lost to follow up. Overall infection rate was 4.9% (95% CI 3.4-7.0). Incidence in the sterile saline group was 6.4%, whereas incidence in the tap water group was 3.5%. The difference was not considered statistically or clinically significant. There were no delayed complications.

 

Limitations: (1) Primary measured outcome of wound infection was determined based on subjective indicators of infection, such as erythema or exudate. Bacterial counts, wound cultures, or wound biopsy were not considered practical. (2) Tap water was approximately 38 degrees Celsius, whereas sterile water was room temperature. The temperature difference was not accounted for.

 

Take home points: Next time you have an uncomplicated laceration, instead of breaking open a bottle of saline, consider just using water from the tap.

 

Image courtesy of www.advancedtissue.com.