Traumatic wound debridement: a comparison of irrigation methods

OBJECTIVES: To test wound debridement efficacy and soft tissue damage produced by high-pressure pulsatile lavage (HPPL), suction irrigation, and bulb syringe irrigation. DESIGN: Randomized trial in an in vitro model. SETTING: Medical school orthopaedic department. PATIENTS/PARTICIPANTS: No patients were used in this study. INTERVENTION: Beef flank steaks (100-g +/- 10-g) were divided into 8 test groups and incised uniformly. Four test groups were contaminated with 2 g of rock dust and 4 were not. The specimens were then treated as follows: nothing (control), bulb irrigation, suction irrigation, or HPPL. MAIN OUTCOME MEASUREMENTS: Runoff from the irrigation was collected, filtered, lyophilized, and ashed to allow for quantitative determination of organic and inorganic material removed from the wound by each irrigation method. Digital photographs of the tissue samples were subjected to blinded grading on a scale of 1 to 5 to assess macroscopic soft tissue damage. RESULTS: Qualitatively, tissue samples treated with HPPL consistently received worse grades for tissue damage than samples in any other experimental group. Quantitative soft tissue damage analysis revealed that significantly more organic material was removed from samples treated with HPPL (141.3 +/- 58.9 mg) than those treated with bulb syringe (50.7 +/- 28.6 mg) or suction irrigation (108.7 +/- 174.5 mg). Surprisingly, significantly less inorganic contaminant was removed from tissue samples treated with HPPL (1549.6 +/- 77.3 mg) than those treated with bulb syringe (1834.9 +/- 39.1 mg) or suction irrigation (1827 +/- 39.4 mg). CONCLUSIONS: There has been some concern regarding damage produced by HPPL. According to our quantitative soft tissue damage data, tissue treated by HPPL was damaged significantly more than tissue treated with bulb syringe or suction irrigation. Our qualitative tissue damage grade data showed that HPPL treated test groups appeared more damaged than other irrigation groups. Surprisingly, HPPL removed significantly less inorganic contaminant than other debridement methods, and it is proposed that HPPL may drive some contaminants deeper into the tissue rather than removing them. This study seems to support the concept that suction and sharp debridement, as practiced by most surgeons, may remove foreign bodies well without the use of HPPL.     

A novel method of studying wound healing

In order to study wound healing, it is often necessary to administer various wound-active substances by the systemic route. It is unclear whether the observed effects are the result of local or systemic influence of the agent administered. Furthermore, high systemic doses are often required to achieve activity at the wound level. Direct intrawound administration of substances is traumatic and disruptive to the fragile wound environment and increases the risk of infection. We devised a system for continuous atraumatic delivery of substances directly to subcutaneously implanted polyvinyl alcohol sponges, an adaptation of a well-established model of wound healing. Sponge-catheter constructs were fashioned by feeding identical lengths of silicone catheters through two 40-mg sponge disks (on edge). The distal sponge was fixed 0.5 cm from the distal, ligated end of the catheter and centered over two 1-mm holes in the catheter tubing. The proximal sponge was fixed over nonperforated catheter with its edge 2 cm proximal from the close edge of the distal sponge. Each construct was connected to a mini-osmotic pump (infusion rate 1 microl/h) loaded with an appropriate infusate and inserted subcutaneously on the dorsum of anesthetized male Sprague-Dawley rats. Hydroxyproline (OHP) content of sponges, a measure of collagen deposition, was determined at 7 days postwounding. Infusion of India ink confirmed selective delivery to the distal sponge. Saline infusion alone significantly elevated OHP content compared to noninfused sponges (450 +/- 43 vs 328 +/- 36 microg OHP/100 mg sponge, P < 0.05). Infusion of S-methylisothiourea (a selective iNOS inhibitor, 84 microg/sponge/24 h) successfully inhibited NO production (35.9 +/- 3.1 vs 49.6 +/- 3.6 microM, P < 0.05) and decreased sponge OHP content (385 +/- 60 vs 568 +/- 70 microg OHP/100 mg sponge, P < 0.05) without the toxic side effect (i.e., weight loss) seen with systemic administration. Infusion of an adenoviral solution containing mouse iNOS cDNA resulted in successful transduction of wound cells demonstrating the ability to deliver genes to a healing wound model. The data demonstrate that manipulation of wound physiology is possible by local delivery of low doses of wound-active compounds to the wound site. This promises to be a powerful tool for the study of both normal and impaired wound healing.     

Nurses' knowledge of wound irrigation and pressures generated during simulated wound irrigation.

OBJECTIVE: Our objective was to describe nurses' knowledge of wound irrigation and their ability to produce appropriate irrigation pressures established by the US Agency for Healthcare Research and Quality (AHRQ) during simulated procedures. Subjects and setting: A convenience sample of 28 registered nurses and licensed practical nurses from a university medical center in the Northwest United States comprised the subjects. METHODS: Participants were asked to complete a demographic data sheet and a questionnaire related to wound irrigation and to perform 2 simulated wound irrigations. The questionnaire developed for the study contained 9 questions about general knowledge of wound irrigation and 9 questions about wound irrigation technique. A device to measure the pressures generated by the participants during simulated wound irrigation was developed and calibrated using a transducer calibrated by the National Institute of Science and Technology. RESULTS: Participants' scores were high on items querying general knowledge of wound irrigation but lower on questions relating to irrigation technique. Thirteen participants achieved irrigation pressures within the guidelines established by the AHRQ, 14 fell below the guidelines, and 1 produced pressures exceeding the guidelines. CONCLUSION: The majority of nurses participating in this small study had some difficulty answering questions relating to wound irrigation technique. In addition, performance on simulated irrigation showed that the majority were not able to generate pressures in the recommended range. Nursing professionals and educators should be aware of these knowledge and performance issues and incorporate educational content and experiences in nursing programs designed to aid nurses in improving wound irrigation practice.     

Electrolyzed strong acid aqueous solution irrigation promotes wound healing in a burn wound model

The purpose of the study was to understand the effectiveness of electrolyzed strong acid aqueous solution (ESAAS) for acceleration of epithelialization in a rat burn wound model. Eighteen anesthetized Sprague-Dawley rats received 30% total body surface area third-degree burns, and 2 days after injury, the wound eschars were removed. Rats were divided into 3 groups: Group 1, no irrigation; Group 2, irrigation with physiological saline; and Group 3, irrigation with ESAAS. Wounds were observed macroscopically until they were fully epithelialized, and epithelialized wounds were examined microscopically. Epithelialization of the wounds occurred significantly early in the rats treated with ESAAS (p < 0.05). Proliferation of associated lymphocytes and macrophages was more extensive in all rats that underwent irrigation than it was in control rats. ESAAS irrigation may promote tissue growth in burn wounds.     

Simultaneous irrigation and negative pressure wound therapy enhances wound healing and reduces wound bioburden in a porcine model

Infected foot wounds are one of the most common reasons for hospitalization and amputation among persons with diabetes. The objective of the study was to investigate a new wound therapy system that employs negative pressure wound therapy (NPWT) with simultaneous irrigation therapy. For this study, we used a porcine model with full‐thickness excisional wounds, inoculated with Pseudomonas aeruginosa. Wounds were treated for 21 days of therapy with either NPWT, NPWT with simultaneous irrigation therapy using normal saline or polyhexanide biguanide (PHMB) at low or high flow rates, or control. Data show that NPWT with either irrigation condition improved wound healing rates over control‐treated wounds, yet did not differ from NPWT alone. NPWT improved bioburden over control‐treated wounds. NPWT with simultaneous irrigation further reduced bioburden over control and NPWT‐treated wounds; however, flow rate did not affect these outcomes. Together, these data show that NPWT with simultaneous irrigation therapy with either normal saline or PHMB has a positive effect on bioburden in a porcine model, which may translate clinically to improved wound healing outcomes.     

Continuous wound irrigation in the pig

It was demonstrated in the pig that full-thickness wounds in the skin can be continuously treated by irrigation for several days. Irrigation was accomplished through a porous, occlusively applied dressing having two ports, one for supply and one for drainage. The fluid, delivered by means of an iv set, was sucked through the inert dressing, leaving it partially saturated, and with fluid spread evenly through its pores. Particulate matter was removed along narrow paths converging on the outlet, not showing any significant diversion. The apparatus for fluid supply and drainage was arranged to move with the animal, thus eliminating the risk of obstruction of the tubes as a result of twisting. The fluid was eliminated by one suction line, and the vacuum in the dressing maintained by another. This allowed the suction to be adjusted to a level near the atmospheric pressure.     

Suction/irrigation for deep wound infection after spinal instrumentation: a case study

Deep wound infection after spinal instrumentation is a serious complication that is difficult to treat without removing the instruments and bone graft. Debridement and suction/irrigation is an effective method of treatment in these cases. It was performed on six patients in our department who developed this complication between 1985 and 1994. Four patients with early post-operative infection were cured by this method without removing the instruments and bone graft, and two patients with delayed post-operative infection were cured by this method with instrument removal. Debridement and suction/irrigation is a useful method of treatment for both groups of deep wound infection and gives good results when performed soon after infection onset together with additional antibiotic therapy.     

Povidone‐iodine wound irrigation: A word of caution

Iodine‐based disinfectants are widely used by various surgical specialties to prevent and treat wound infection; however, its detrimental effects are often overlooked. We hereby report a dialysis‐dependent renal failure patient with clinical manifestation of systemic iodine toxicity after irrigation of an infected mediastinal wound with povidone‐iodine solution. Further study is required to determine the systemic absorption and side‐effect profile of povidone‐iodine especially when used for irrigation of deep body structures.     

A novel noncontact method to assess the biomechanical properties of wound tissue

A novel noncontact optical coherence tomography based air‐jet indentation system was developed for characterizing the biomechanical properties of soft tissue in a noncontact way. This study aimed to measure the stiffness of diabetic foot ulcer tissues by using this air‐jet indentation system, and examining the test/retest reliability. Eight subjects with diabetes (seven males, one female), with a total of 10 foot ulcers between them, participated in the study. A total of 20 measuring sites located at the central wound bed (n=10) or peri‐ulcer areas (n=10), respectively, were evaluated with the air‐jet indentation system. Four cycles of loading and unloading, each with a duration of approximately 36 seconds at an indentation rate of 0.08 mm/s, were carried out for each indentation trial. The test/retest reliability was examined at all measuring points. The average stiffness coefficient of the peri‐ulcer area (mean±SD: 0.47±0.15 N/mm) was significantly larger than that of the central wound bed area (mean±SD: 0.35±0.23 N/mm; p=0.042). A high value for test/retest reliability was shown (intraclass correlation coefficient: 0.986; Pearson's correlation: r=0.972, p<0.001). Our preliminary findings showed that the peri‐ulcer area had greater stiffness than the central wound bed. This greater magnitude of hardness and inelasticity at the peri‐ulcer region may scatter part of the contractile forces for wound contraction during the healing process. We found the novel air‐jet system to be a reliable tool for characterizing the stiffness of soft tissues around the wound in a noncontact way.