Efficacy and Safety of the Application of Local Anaesthetic in Spray to Repair of 1st- 2nd Perineal Lacerations

The study aims to compare the effectiveness of pain treatment during the suturing of postpartum perineal lacerations with lidocaine spray vs skin infiltration. The hypothesis of the study is that the treatment of perineal pain with nebulization demonstrates comparable efficacy vs the infiltration of mepivacaine hydrochloride in a population of patients subjected to suturing of postpartum lacerations. Eligible women will be randomly assigned to receive, after wound disinfection and cleansing of bleeding with mild haemostasis:

• nebulization 3 puffs of 10 mL Lidocaine hydrochloride 10% spray at a distance of 4-5 cm (experimental group).
• subcutaneous / submucosal infiltration depending on the type of perineal laceration of 10 ml of 1% mepivacaine hydrochloride (control group).

Since there are no previous published studies, regarding the use of nebulized lidocaine hydrochloride for the suturing of perineal lacerations, the number of puffs chosen was chosen based on what is indicated on the technical data sheet of lidocaine hydrochloride and making use of previous studies in the gynecological field, but with other indications.

The suture will be made once anesthetic efficacy is achieved, as per pharmacological indications. The administration of the anesthetic and the suturing of the lacerations will be performed by the gynecologist or by the gynecology resident who will be working at that time in the delivery room, as is routinely done in our Clinic. The patients will be enrolled consecutively following the order generated by the randomization list itself. By filling in specific pre-set cards, the data will be collected.

Initially, the primary outcome was NRS at the beginning of suturing and NRS at the end of the procedure. In a second moment, the investigators thought it would be better to ensure that adequate analgesia (NRS<4) was achieved for all patients during suturing, rather than varying the dosage of the anesthetic itself. The investigators then decided to reassess pain at successive time points, evaluating it at 0, 2, 4, 12, and 24 hours.

Inclusion criteria

• have a 1st or 2nd degree postpartum perineal laceration requiring suturing;
• have reached 37 gestational weeks;
• are over 18 years of age;
• had a top birth;
• are able to understand the Italian language;
• have a consent to participate in the study;

Exclusion criteria

• have received epidural anesthesia within 2 hours prior to delivery;

• had an operative birth;
• have a psychiatric pathology;
• have had a twin birth;
• have experienced adverse reactions to any local anesthetic in the past;
• hypersensitivity to the active substance or to any of the excipients
• Severe disturbances of the cardiac conduction system
• Acute non compensated heart failure
• Severe arteriopathies
• Severe uncontrolled hypertension
• Intravascular injections
• Septicemia Dysfunction
• Infection at the injection site
• Kidney failure. Providing for the exclusion of patients with severe renal impairment (estimated GFR <30 mL / min / 1.73 m2 at the time of screening).
• Advanced liver dysfunction
• Hyperthyroidism
• Acute angle glaucoma
• Participation in a clinical trial in which an investigational drug was administered within 30 days of screening or 5 half-lives of the study drug
• Any clinical condition that in the investigator's judgment would render the patient unsuitable for the study including, but not limited to, infectious, inflammatory, psychiatric, neurological, cardiological, renal, hepatic, respiratory, diabetes) conditions or laboratory value at clinically meaningful screening that, an investigator's opinion, may present a safety risk, interface with study compliance and follow-up;
• have had in pregnancy liver disease including pre-eclampsia.