The effect of pethidine hydrochloride on the cervical muscles in the active phase of labour.
The effect of pethidine hydrochloride (PHC) on the smooth muscles of cervix was studied in the active phase of induced labour in 27 primiparous women. The Electromyographic (EMG) root mean square (RMS) which provides information about the amplitude (intensity) of muscular cervical activity, and the median frequency (MF) which represents the EMG frequency spectrum were analyzed in connection with the intensity of intra-uterine pressure (IIUP). The RMS significantly decreases after the application of PHC, while the IIUP significantly increases. The effect of the applied drug disappears in one hour's time. The MF values increase insignificantly after the application and change in the opposite direction to the change of MSR. The change RMS, MF and IIUP values do not correlate with the duration of the active phase of labour.
Pajntar
M
M
University Department of Obstetrics and Gynecology, Ljubljana, Slovenia.
Valentincic
B
B
Verdenik
I
I
D002584:Cervix Uteri / Q000187:drug effects* / Q000502:physiology; D004576:Electromyography; D005260:Female; D006801:Humans; D007743:Labor, Obstetric / Q000502:physiology*; D008614:Meperidine / Q000494:pharmacology*; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D011247:Pregnancy; D011312:Pressure; D012044:Regression Analysis; D014599:Uterus / Q000502:physiology
D008614:Meperidine