Lacerations of the perineum : their causes, formation, and primary repair : with report of forty-eight illustrated cases / by Ellice McDonald.

  • McDonald, Ellice, 1876-1955.
Date:
1908
Catalogue details

Licence: In copyright

Credit: Lacerations of the perineum : their causes, formation, and primary repair : with report of forty-eight illustrated cases / by Ellice McDonald. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Of these, Emmet (17) has been the greatest contributor toward the subject and recognized that the torn muscles and fasciae caused a loss of support to the pelvic floor. His operation is the one commonly performed at the present time. Since the time of these masters, a multitude of new operations have been devised to restore the anatomical support of the pelvic floor and close the perineal wound, caused by descent of the head at labor. All these operations have as their aim the intimate approximation of the edges of the torn fasciae and muscles. To this end, in secondary operations, many forms of denudation of the vaginal mucous membrane have been exploited. The majority of these attempt the excision of the scar tissue of the old wound and the restoration of the torn mus- cles and fasciae. Without a proper appreciation of the causes, processes, and forms of perineal rupture, it is useless to attempt to judge the value of each modification of the various operations. With this end in view I have made sketches of forty- eight consecutive perineal lacerations at the time of labor and have noted the most evident and directly causative factors. These lacera- tions occurred in 100 women, of whom go were primiparae. This gives a percentage of occur- rence of forty-eight percent, which is within Williams’ estimate of 45 to 58 per cent. Every wound of the mucous membrane other than a small tear of the fourchette has been reckoned in the series, none over 1.5 cm. in length have been excluded. The various causes of perineal laceration are usually cited as follows: 1. Too rapid expul- sion of the child, so that tearing of the perineum instead of stretching results; 2. Relative dis- proportion between the presenting part and the parturient outlet; 3. A faulty mechanism of labor whereby the largest circumference of the head passes the perineal ring; 4. The use of forceps. Rapidity of delivery is without doubt the most frequent cause of perineal laceration. This is particularly seen in those cases of pre- cipitate delivery where the head comes through the birth canal rapidly and impinges upon the perineum with almost the force of a blow. This rapidity of advancement of the head is sometimes seen in cases of contracted pelvis, where strong uterine pains are required to force the head through the bony pelvis, with the result that the less resistance of the soft parts does not retard its way. The quick descent of the head was also seen in one case (No. 25), where the membranes had remained intact until the head had come through the brim; when the membranes ruptured, the head was advanced with great rapidity, causing a laceration in a multipara with a compara- tively lax outlet. The passing of the head through the perineal outlet should undoubtedly be retarded, until the parts have softened and stretched. A pre- liminary digital stretching .is most useful in primiparae, although often a painful proced- ure. It can, however, be done during the labor pains and is a means of stimulation of their force and frequency. A frequent cause of perineal laceration is the pressure of the head upon the perineal body and the lack of retraction between pains. The maternal parts become bloodless and tense, and tear readily with further descent of the head. An additional factor in the produc- tion of this condition is the attempt to control expulsion by pressing the taut perineum against the sinciput. This wounds the perineum and aids in the production of the anemic condition. The advancement of the head should be con- trolled without making any pressure upon the perineum. Strong pains are a definite factor in the pro- duction of perineal injuries, but may be readily controlled by chloroform. Relative disproportion between the present ing part and the parturient outlet is commonh thought to be one of the main causes of perineal injuries. In any attempt to estimate the size of the fetal head in relation to the perineum, it should be decided which is the greatest diameter of the fetal head to' engage in the perineal ring. In this study, it will be considered to be the occipito-frontal diameter, which comes into relation with the perineum by the final exten- sion of the head. It is the diameter most capable of accurate measurement and gives a more dependable estimate of the size of the fetal head than do the suboccipito-bregmatic