to evaluate reduction of pain in wounds treatment previously applying lidocaine topical solution vs placebo

Conditions: Wounds; Local Anesthesia

Summary: 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 pilot, single-center clinical trial, prospective, randomised, double-blind, placebo-controlled study that will include 26 patients admitted in bellvitge university hospital (hub) who present painful wound treatments. the pharmaceutical department of hub prepares a dilution of lidocaine 0.5% in 20ml disposable syringes and also identical disposable syringes containing 20ml saline solution (process authorized by the spanish agency of medicines and sanitary products). each patient included will be subject to 6 procedures, randomised according to the sequence of treatment ababab or bababa ("a" is lidocaine solution, "b" is placebo solution), according to a random list. after a doctor of the pain department evaluates and includes the patient into the study, prescribes the treatment and the pharmaceutical department provides 3 identical syringes (numbered), for each procedure, to the nurse of the patient. the first syringe will contain always saline solution (this is unknown for the patient and the nurse) doing this, the investigators obtain the basal pain of each procedure. the other two syringes contain the studying solution (lidocaine or saline solution, according the sequence of the random list) but always the same solution in both. the doctors of the pain department ask the patient about the pain before starting the procedure and determine according the "verbal numerical scale" (vns) from 0 to 10 points. the nurse, under sterile conditions, will dampen two sterile gauzes with the solution contained in the syringe 1, and will apply on the wound during 10 minutes before starting the treatment. after this time, the nurse starts the treatment of the wound and the doctor asks again about the pain punctuation on the vns and register it. all this procedure is repeated with the contain of the syringe 2 and register the punctuation. if the procedure is still painful, the nurse applies (following the same procedure) gauzes with the solution contained in the syringe 3 and the doctor register the vns punctuation. if even this third application, the treatment is still painful, each patient has prescribed a systemic analgesic to be used at this point if necessary (it does not matter which analgesic, the best for each patient, the only condition is that it can not be modified during the period of inclusion into the study, it is, 6 procedures) and the punctuation in the vns is also registered. furthermore, during each procedure, the nurse and the doctor, control the appearance of side effects and 7 days after the last procedure, the doctor contacts to the patient for check the clinical safety. comparing the procedures carried out after lidocaine solution with saline solution, the investigators will evaluate the reduction of pain in the wounds treatment.

Eligibility criteria:
inclusion criteria: * patient who has accepted and signed the informed consent before the random process. * patients with painful wound treatments * wounds or sores of any aetiology (vascular insufficiency, diabetics, traumatic, postsurgical...) 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. * men and women in fertile age using contraceptive measures exclusion criteria: * precedents of allergic reaction to local anesthesics type amides. * wounds or sores degree i on the gneaupp classification (without discontinuity of skin). * wounds or sores too large (which require more than 40 ml of solution to cover). * wounds around the eyes. * 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. * patients who refuse to participate in the study. * patients requiring wounds treatment more than once each day.

Keywords: wound treatment lidocaine pain reduction local anesthetic