To Evaluate Reduction of Pain in Wounds Treatment Previously Applying Lidocaine Topical Solution vs Placebo.

Double-blind Randomized Clinical Trial to Evaluate the Reduction of Pain in the Wounds Treatment Previously Applying Lidocaine Topical Solution vs Placebo, in the Outpatients Area.

The purpose of this study is to evaluate if applying a lidocaine topical solution before wounds treatment decreases the pain of the procedure in comparison with placebo solution.

The manipulation of the wounds for its treatment is a painful process and there is currently no marketed any topical drug to decrease this suffering.

The objective of this study is to demonstrate that lidocaine topical solution applied prior to wounds treatment, reduces the pain of the procedure compared to the treatment done after application of placebo solution. In addition, if the process was less painful, the consumption of systemic analgesics would be reduced (or eliminated) and, therefore, also its secondary effects.

It is a single-center clinical trial, prospective, randomised, double-blind, placebo-controlled study that will include 46 patients (23 lidocaine group, 23 placebo group) who presents painful wounds during treatment in the Bellvitge University Hospital (HUB) outpatients area.

The Pharmaceutical Department of HUB prepares a dilution of lidocaine 0.5% in 20ml disposable syringes and identical disposable syringes containing 20ml saline solution (process authorized by the Spanish Agency of Medicines and Sanitary Products).

When a patient arrives at the outpatient area (dermatology or plastic surgery departments) to treat a wound, the nursery or the doctor who does the procedure evaluates the pain during the treatment. If it is 5 or more points according the "Verbal Numerical Scale" (VNS), the nursery will explain to the patient the possibility of being a participant in this study, and give the information document. If the patient is interested, the doctor of the Pain Department will be warned and an EKG and a pregnancy test (if the patient is a woman in fertile age) will be done.

The doctor of the Pain Department will answer to any question about the study, will collect the medical record, will evaluate de EKG and the pregnancy test if it was done. Counting with all this information, and checking inclusion/exclusion criterias, the patient will be recluted. The patient will be ask to register in a data document any analgesic needed in the following 24 hours and also to register the VNS punctuation (0-10) 24 hours after the procedure, and to bring all this information the day of the next wound treatment. To avoid bias, the doctor of the Pain Department, will ask the patient to take the same analgesics the day of the study.

Between the basal wound treatment (it is, the day of the recruitment) and the wound treatment of the study (it will be the next wound treatment, when lidocaine or placebo will be applied, depending on the random list) there will not elapse more than 10 days.

The random process, will be done in the Pharmaceutical Department, following a table of random, starting at numer 01. The pair number will receive lidocaine, and the odd numbers saline solution. Each syringe will be named by an ordinary number, according with the recruitment number. And they will give this syringes to the outpatient area.

The day of the study, the nursery or the Pain Department doctor will record the VNS punctuation before treatment; then the nursery will apply wetted gauzes with the study solution and will wait 7-15 minutes to effect (exactly time counted and registrered with a chronometer). After this time the habitual treatment will be applied and at this moment the pain in the VNS will be recored. The nursery or the Pain Department doctor will be attentive to any secondary effect appears. And finally, the nursery will ask again about the pain 15 minutes after the procedure.

The nursery or the Pain Department doctor will ask to the patient to record the analgesics need in the following 24 hours and, after this period, the Pain Department doctor will call the patient to ask about this record, about the pain at 24 hours after the procedure and if any secondary effect has been detected.

Comparing the procedures carried out after lidocaine solution with saline solution, the investigators will evaluate the reduction of pain in the wounds treatment.

Inclusion Criteria:

• Patient who has accepted and signed the informed consent before the random process.
• Women or men aged more than 18 years
• Patients with painful wound treatments (> or = 5) who come to outgoing area for the treatment
• Wounds or sores of any aetiology sauf arterial deficit that implies at minimum dermis or epidermis, it is, II to IV degree in the Spanish Classification of Sores made by the "National Group to Study and Management of Pressure Ulcers and Chronic Wounds" (GNEAUPP).
• Women in fertile age with pregnancy test negative

Exclusion Criteria:

• Precedents of allergic reaction to local anesthesics type amides.
• Wounds or sores degree I on the GNEAUPP Classification (it is, without discontinuity of skin).
• Wounds or sores too large (which requirej more than 40 ml of solution to cover)
• Wounds around the eyes
• Wounds secondary to arterial deficit
• Patients who presents disturbance of cardiac conduction: atrioventricular block (second or third degree) or bifascicular block
• Patients with altered level of consciousness (Glasgow Coma Scale value less than 14)
• Patients following hemodialysis, peritoneal dialysis or continuous hemofiltration treatment
• Patients suffering moderate or severe hepatic insufficiency
• Pregnant or lactating women
• Once the patient has already participate in the study during a previous wound treatment
• Patients who refuse to participate in the study