Increased density of sensory nerve fibres in the endometriotic lesions and in the eutopic endometrium have also been found . Pertubation comprises passing solution through the uterine cavity and the fallopian tubes into the peritoneal cavity via a cuffed intra-cervical balloon catheter. Earlier studies have shown that pertubations with lignocaine hydrochloride can improve fertility and reduce dysmenorrhoea in patients with endometriosis [7–9]; the highest dosage
of lignocaine in these studies has been 10 mg. In total, more than 400 pertubations with lignocaine have been carried out without any lignocaine-related adverse events. Local anaesthetics in low concentrations have anti-inflammatory learn more properties, and the clinical effect seen on pain and fertility might be due to decreased inflammation in the peritoneal cavity . The adverse P-gp inhibitor effects of lignocaine have been well investigated and manifest most commonly on the central nervous
system (CNS) and cardiovascular systems [10, 11]. Plasma concentrations of lignocaine above 5 μg/ml can cause adverse effects (i.e. nausea, dysphoria, drowsiness, cardiovascular instability), but concentrations of lignocaine above 10 μg/ml are needed to produce serious toxicity. Serum levels above 10 μg/ml can cause disorientation, respiratory depression, seizures and even coma, but serum levels exceeding 20 μg/ml are needed to cause cardiovascular collapse . Serum levels of local anaesthetics after non-vascular administration correspond with the vascularity of the tissue . The surface area of the peritoneum is about equal to that of the skin, i.e. >2 m2. Small molecules diffuse rapidly and the diffusion rates decrease with the molecular weight to become extremely slow for molecules Methocarbamol with a molecular weight of
100,000 Da [13–15]. Lignocaine hydrochloride has a molecular weight of 271 Da. A review of systemic levels of local anaesthetics after intra-peritoneal application was conducted in 2010; nine trials in which lignocaine was used were found . The dosage used varied from 100 to 1,000 mg, and serum levels were detected as early as 5 min after application, with a time to maximum SC79 concentration (T max) ranging from 5 to 40 min for plain lignocaine. The addition of adrenaline prolonged the T max. Mean concentration maximum (C max) ranged from 1.01 to 4.32 μg/ml, and the highest observed value was detected after intraperitoneal administration of 80 ml lignocaine 0.5 % (400 mg) . No report of serum or clinical toxicity was found in any of the reviewed studies . We have previously reported a randomized controlled trial that was carried out to evaluate the effect of pertubation with lignocaine 10 mg on dysmenorrhoea and quality of life in patients with endometriosis.