Impedance Spectroscopy in Detection of Obstetric Anal Sphincter Injuries

Evaluation of the Effectiveness and Safety of Impedance Spectroscopy Device in Detecting Sphincter Injuries in Women After Natural Delivery

The main purpose of the study is to evaluate the effectiveness and safety of the impedance spectroscopy device prototype in detection of anal sphincter injuries in women in the early postpartum period. The study is prospective. The study group comprises 24 patients; included in it 6-8 weeks after natural delivery. The planned participation of each patient in the study is up to 4 weeks and three visits will take place at that time. After obtaining written consent, at the screening visit (V0) each patient will undergo a physical examination, blood samples for laboratory tests and stool samples for calprotectin concentration assessment will be collected. On the second visit (V1), after the final verification of inclusion/exclusion criteria, impedance spectroscopy using tested device will be performed in each patient, the electrical impedance of pelvic floor muscles will be measured and the degree of anal sphincter damage will be evaluated. Full gynecological and proctological examination (including a gynecological speculum, two-handed examination, rectal examination and anoscopy) will be carried out. On the third visit (V2), two reference diagnostic tests (with evidenced effectiveness and safety), transanal ultrasonography and anorectal manometry, will be conducted. The collected data will be used to select the optimal therapeutic method for each participant individually.

24 women will be included in the study and divided into two subgroups. 12 of them (first subgroup) came from patients within 6 to 8 weeks after natural delivery, that had a perianal tear of grade 1 or 2 in OASIS classification. Remaining 12 (second subgroup) came from patients within 6 to 8 weeks after natural delivery, that had a perianal tear of grade 3 or 4 in OASIS classification. The planned interventions are: Blood and faeces tests Impedance spectroscopy test Full gynecological and proctological examination Transanal ultrasonography Anorectal manometry

During V1 - Examination with a gynecological speculum, Two-handed examination, Rectal examination and Anoscopy

During V2 - reference diagnostic methods with documented effectiveness and safety; for comparison with impedance spectroscopy results.

During V2 - reference diagnostic methods with documented effectiveness and safety; for comparison with impedance spectroscopy results.

Assessed by subsequent measures: Sphincter continuity in physical examination, Sphincter tension in physical examination, OASIS classification of perineal tears in transanal ultrasonography Starck scale for classification of anal sphincter injuries in transanal ultrasound (0-16 scale, no defect - 0; maximum - 16, means severe damage of both sphincters on a considerable length and circumference) Norderval scale for classification of anal sphincter injuries in transanal ultrasound (0-7 scale, no defect - 0, 7 is the maximal damage of both anal sphincters) anorectal manometry assessment to measure anal sphincters function All measurements are used to estimate the presence, extent and severity of anal sphincter injury. The main aim of the study is to establish whether the extension and severity of obstetric anal sphincter injury can be precisely assessed with parameters calculated from pelvic floor muscles using impedance spectroscopy.

Evaluation of the frequency and intensity of adverse events associated with the use of the new diagnostic method.

Inclusion Criteria: after natural delivery and post-partum period (6-8 weeks after delivery) physiological pregnancy observed a perianal tear of grade 1-4 in the OASIS classification signed informed consent Exclusion Criteria: presence of acute diseases during treatment presence of chronic diseases untreated or insufficiently treated (e.g. poorly controlled hypertension), presence of diseases, with symptoms of fecal incontinence, previous proctological operations, the presence of inflammatory bowel diseases in the stage of exacerbation, treatment in the last year due to severe, progressive, uncontrolled cardiac, pulmonary, nephrological, infectious or psychiatric disease, which course could affect the patient's risk due to participation in study, significant deviations from the norm in a physical examination during V0 visit or laboratory tests taken during the same visit, significant disease symptoms so far undiagnosed and reported during the V0 visit presence or suspected malignant disease or previous oncological treatment during the last 5 years, presence of a cardiac stimulator or cardioverter-defibrillator, severe surgery or severe trauma in the last year.