Free WCC Practice Test
1. Which of the following wound irrigation devices will provide approximately 8 psi in irrigant pressure to the wound surface?
- 35-mL syringe with 19-gauge Angiocath
- 250-mL squeeze bottle
- Bulb syringe
- 6-mL syringe with 19-gauge Angiocath
2. A patient with an infected abdominal wound is taking a number of drugs. Which of the following is most likely to impair healing?
3. Using transcutaneous oxygen pressure measurement (TCPO2), which of the following values indicates that oxygenation is adequate for healing?
- 18 mm Hg
- 20 mm Hg
- 30 mm Hg
- 42 mm Hg
4. A patient has second and third degree burns on 30% of the body and is in severe pain. Which method of debridement is most indicated?
- Autolytic debridement
- Enzymatic debridement
- Sharp instrument debridement
- Surgical debridement
5. Which method of mechanical debridement may cause damage to granulation tissue and is generally contraindicated?
- Wet to dry dressings
- Whirlpool bath
- Irrigation under pressure
- Ultrasound treatment
Answers and Explanations
- A: A 35-mL syringe with 19-gauge needle provides irrigation pressure at about 8 psi. A squeeze bottle (250 mL) provides about 4.5 psi, but a bulb syringe usually only <= 2 psi. Both syringe/catheter and needle size affect irrigant pressure. Pressures < 4 psi do not provide adequate wound cleansing, but pressures >15 psi can result in wound trauma.
- 6 mL/19 gauge = 30 psi
- 12 mL/19 gauge = 20 psi
- 12 mL/22 gauge = 13 psi
- 35mL/21 gauge = 6 psi
- 35mL/25 gauge = 4 psi
- B: Corticosteroids may impair wound healing by interfering with vascular proliferation and epithelialization. The anti-inflammatory effect may interfere with the inflammatory phase of healing by decreasing migration of macrophages and polymorphonuclear leukocytes to the wound, interfering with angiogenesis, and increasing susceptibility to wound infection. Other drugs that may impair healing include vasoconstrictors, NSAIDs, aspirin, colchicine, immunosuppressant's, DMARDS (antirheumatoid arthritis drugs), and anticoagulants. Some drugs appear to promote wound healing, including phenytoin, prostaglandin, and estrogen.
- D: Transcutaneous oxygen pressure measurement (TCPO2) is a noninvasive test that measures dermal oxygen, to show the effectiveness of oxygen in the skin and tissues. A value of >40 mm Hg indicates adequate oxygenation for healing. Values of 20 to 40 mm Hg are equivocal findings, and values < 20 mm Hg indicate marked ischemia, affecting healing. Two or three different sites on the lower extremities should be tested to give a more accurate demonstration of oxygenation. TCPO2 is often used to determine if oxygen transport is sufficient for hyperbaric therapy.
- D: Surgical debridement is most commonly used when very large amounts of tissue must be debrided, such as with extensive burns or when there is immediate debridement is needed in order to effectively treat a serious wound infection. General anesthesia allows extensive debridement to be done without the patient suffering associated pain and trauma, although postoperative pain is common. One advantage is that most debridement can be done in one procedure. Lasers may also be used for surgical debridement, with pulsed lasers posing less risk to adjacent tissue than continuous lasers.
- A: In the past, wet-to-dry gauze dressing were frequently used for wound care; but wet-to-dry dressings have little use in current wound care unless the wound is very small, because the gauze adheres to the wound and can disrupt granulation or epithelization. While a whirlpool bath may effectively cleanse debris from a wound, concerns about cross infection have resulted in less frequent use of the whirlpool. Ultrasound may effectively debride wounds. Irrigating a wound with pressurized solution can be effective if the pressure remains in the optimal range, usually 8 to 12 psi.
Last Updated: 12/14/2017