Received: 12-Nov-2022, Manuscript No. gpmp-22-79620; Editor assigned: 13-Nov-2022, Pre QC No. P-79620; Reviewed: 28-Nov-2022, QC No. Q-79620; Revised: 05-Dec-2022, Manuscript No. R-79620; Published: 29-Dec-2022
Background: Obstetric anal sphincter injuries (OASIS) are reported to depend greatly on episiotomy angle. Episiotomy is done in almost all forceps deliveries.
Aim: To evaluate the extent of vaginal and perineal trauma using the angled episiotomy scissors versus straight scissors.
Design: Prospective comparative observational study conducted in 2 hospitals in Saudi Arabia.
Methods: 60 patients delivered by forceps were divided in 2 groups; angle episiotomy group (n=30) vs. straight episiotomy group (n=30), with each having given birth to in a different hospital. The primary outcome measures were the suture angle, suture distance from midline, length of episiotomy, and occurrence of OASIS. Secondary outcomes were pain and neonatal outcomes.
Results: Women with the angled episiotomy scissors, compared with those with straight scissors, had significantly higher post-delivery suture angle, and a longer post-delivery distance from midline. OASIS was significantly lower among angled episiotomy scissors group than among straight scissors group. There were no significant differences between both groups regarding pain or neonatal outcomes.
Conclusion: There has been a statistically significant reduction in OASIS in angled episiotomy scissors group during forceps assisted vaginal delivery and thus we recommend this.
OASIS; Forceps delivery; Angled episiotomy scissors; Episiotomy
Episiotomy was introduced in 1950as a prophylactic procedure to decrease the risk of vaginal and perineal tears as well as to fasten delivery . In a Cochrane review in 2017 there was no evidence that routine episiotomy has the previously assumed benefits and concluded that more restricted use of episiotomies will result in lesser women with severe perineal or vaginal trauma . WHO, 2018 recommend episiotomy performance only when there is a strong clinical indication .
In the study of Zhu et al., 2015, It was reported that during low forceps or outlet delivery the use of episiotomy may decrease the rate of vaginal and perineal tears which in turn decrease the amount of intrapartum hemorrhage and decrease the post-episiotomy pain . There are relative indications in second stage of labor for performing low and outlet forceps delivery include; delay of progress of second stage of labor, inability of patient to push especially with increase in use of epidural analgesia, non-reassuring fetal CTG . Also there are strong indications to use outlet forceps in cases of persistent or direct occiptoposterior with delay in descent of head but with head station +2 .
In our study we conducted low and outlet forceps delivery with baby’s head is at +2 station or +3. In a systematic review in 2010, O'Mahony F et al., found that there is no restriction on rotation for this station in forceps delivery .
Obstetric anal sphincter injuries (OASIs) are the leading cause of anal incontinence in women. Episiotomies with a post- delivery suture angle of less than 30° to the midline are more likely to injure the anal sphincter directly, while those with a suture angle of more than 60° are associated with increased incidence of OASIs, as they do not relieve the pressure on the perineum. A safe zone of 40°–60° has been proposed [7,8].
The aim of the study was to evaluate the extent of vaginal and perineal trauma using the episiotomy versus straight scissors. Also, assessment of neonatal APGAR score and birth trauma.
This study is a Prospective comparative observational study conducted in 2 hospitals in Saudi Arabia (both hospitals are of the same class and level). Selection of cases was according to inclusion and exclusion criteria.
Women who underwent normal vaginal delivery were recruited for this trial. All patients were informed about the purpose of the trial, the procedure modalities, and their benefits as well as risks. Patients were asked whether they are prepared to participate in the trial prior to their inclusion. After being screened for the inclusion and exclusion criteria eligible patients were included into the trial.
Inclusive criteria for patients include: Women between the 21 and 30 years of age, vertex presentation, uncomplicated singleton and term pregnancy in active labor (that was defined as the presence of at least three regular, painful uterine contractions over 10 min with cervical dilatation 4 cm or more), Active labor, Patient willingness to randomize to delivery technique. Exclusive criteria for patients include: age below 20 or more than 30 yrs. Malpresentation and malposition such as breech face and oblique lie, evidence of cephalopelvic disproportion, multiple pregnancies, obstetric complications such as pre-eclampsia, antepartum hemorrhage or known fetal abnormality. Maternal unwillingness to undergo randomization.
The Ethical Committee of two hospitals approved this study. All patients willing to participate signed an informed consent immediately after admission to labor ward and were subjected to detailed history taking (personal, menstrual, obstetric & past history), examination (general, abdominal & local pelvic examination), ultrasonography and laboratory investigations (C.B.C, Rh, blood grouping and albumin in urine).
The primary outcome measures were the suture angle, suture distance from midline, and length of episiotomy while secondary outcomes were maternal pain, wound complications and neonatal outcome.
Sample size justification
The study included all women fulfilling the inclusion and exclusion criteria who were admitted between June 2020 and December 2020 at the 2 hospitals.
All patients were subjected to complete history taking (personal, past history of blood transfusion, previous, Obstetrical history: in details such as last menstrual period, expected date of delivery etc. (to exclude any contraindication for vaginal delivery). General and obstetric examination was conducted including fetal lie, fetal presentation, estimated fetal weight, fetal heart rate, uterine contraction, and the amount of liquor. Vaginal examination including cervical dilation, effacement and position, state of fetal membranes, presenting part, position of fetal head, color of liquor and pelvic adequacy.
Group A: Included 30 women who had low or outlet forceps delivery with mediolateral episiotomy with the use of the curved episiotomy scissors in first hospital while Group B: Included 30 women who had low or outlet forceps delivery with mediolateral episiotomy with the use of straight scissors. All forceps deliveries were performed by consultants or senior registrars of the same level of experience in both hospitals.
First group had low forceps vaginal delivery after the cervix was fully dilated and retracted and the membranes ruptured. The urinary bladder was empty, with the use of a catheter. The station of the head was at least +2 in the lower birth canal. The woman was placed on her back, usually with the aid of stirrups or assistants to support her legs. Ascertaining the precise position of the fetal head is paramount accomplished by feeling the fetal skull suture lines and fontanelles.
At this point, the angled episiotomy scissors was introduced vaginally at crowning, and aligned to orient the guide limb vertically from the posterior fourchette to the anus. While a single cut is preferred, a stagger cut was needed for some women. The two blades of the forceps were individually inserted, the left blade first for the commonest occipitoanterior position; posterior blade first if right or left occipito anterior position, then locked. The position on the baby's head was checked. The fetal head was then rotated to the occiput anterior position when it was not already in that position. The baby was then delivered with gentle traction in the axis of the pelvis. Post-delivery angle was measured by placing a protractor transparency on the perineum after delivery and marking the angle with an indelible ink pen. Per rectal examination was performed prior to suturing to detect OASIs.
Other group had a mediolateral episiotomy with straight scissors, before forceps application followed by the same steps.
Perineal repair following delivery
As soon as birth was completed the initial assessment performed gently and sensitively to classify the perineal trauma caused by episiotomy. Third- and fourth-degree trauma excluded from the research. After full explanation of the procedure to the mother, she was placed in a position allowing good visualization, vulval/perineum washed and draped with sterile drapes. The vagina inspected and the apex of the episiotomy or perineal tear identified. If needed, another infiltration with 1% Lignocaine up to a total of 20mls to the area. A gauze maternity tampon was inserted into the upper vagina, above the trauma to absorb any bleeding from the uterus, which may obscure the field of operation.
The vagina was sutured after good visualization of the apex of the wound starting approximately 0.5cm above this point and the vaginal wall was repaired using a continuous non-locking stitch Continued to the hymenal remnants, then the needle placed behind the hymenal remnants and emerge in the center of the perineal muscle. After checking the depth of trauma, the perineal muscles were repaired in one or two layers with the same continuous stitch leaving no dead space . The skin was sutured with subcuticular stitches.
All women were assessed for the primary outcome measures including: suture angle, suture distance from midline, length of episiotomy, and the occurrence of OASIS.
Secondary outcome measures of neoborne APGAR score and any evidence of neonatal birth trauma were assessed after delivery.
In the postnatal ward patients were evaluated for pain using VAS score. Follow up: all participants were assessed in the postpartum visit 7-10 days after delivery for wound healing and pain score.
Recorded data were analyzed using the statistical package for social sciences, version 20 (SPSS Inc., Chicago, Illinois, USA). The comparison between two groups regarding quantitative data with parametric distribution was done by using Independent t-test. Chi-square (χ2) test of significance was used in order to compare proportions between qualitative parameters. Relative risk: The ratio between the risks of the outcome in the patients group to the risk of outcome in the straight scissors group. The confidence interval was set to 95% and the margin of error accepted was set to 5%. So, the p-value was considered significant as the following (p<0.05, Significant and p<0.001 highly significant).
The demographic data was similar in both groups without any statistically significant difference. Regarding the key outcome indicators displayed in (Tab. 1.) in our study: using angled-60 scissors, the average episiotomy suture angle was (40.56 ± 2.24 degrees) CI ± 2.24, IQR =35-44, while with the straight scissors, the angle was (29.48 ± 3.37 degrees) CI ± 3.37 IQR =22.0–36.0, P<0.001).
|Mean ± SD||26.32 ± 2.14||26.21 ± 2.55||^0.857|
|Range||22.0 – 30.0||21.0 – 30.0|
|Mean ± SD||27.85 ± 1.33||28.15 ± 1.22||^0.366|
|Range||25.4 – 31.7||25.2 – 30.8|
|Mean ± SD||38.35 ± 0.71||38.36 ± 0.81||^0.960|
|Range||37.0 – 40.0||37.0 – 40.0|
|Previous NVD||10 (33.3%)||9 (30.0%)||#0.785|
Tab. 1. Demographic characteristics among the studied groups.
Post-delivery mean distance from midline in was (36.12 ± 3.37) in the angled- 60 scissors group while with the straight scissors, the distance was (20.30 ± 3.06) (36.12 mm, 95% CI ± 3.37, IQR =29-44 versus 20.30; 95% CI ± 3.06, IQR =15–27 P<0.001).
Additionally, we discovered that the angled episiotomies were greater in length (47.323.77 mm compared to 42.333.26 mm for the straight episiotomies, P0.001) (47.32 mm, 95% CI 3.77, IQR =38.0-57.0 versus 42.33 mm, 95% CI 3.26, IQR = 40.4-42.6 P0.0001).
OASIS was significantly less frequent among angled scissors group than among straight group.
Tab. 2. Shows no significant difference between angled scissors and straight scissors groups regarding maternal pain and complications at follow up. Tab. 3. shows no significant difference between angled scissors and straight scissors groups regarding Neonatal outcomes. Tab. 4. shows the maternal pain and complications at follow up among the studied groups. Tab. 5. shows the neonatal outcomes among the studied groups.
|Mean ± SD||40.56 ± 2.24||29.48 ± 3.37||<0.001**|
|Benefit of angled scissors over straight scissors|
|Items||Mean ± SE||95% CI|
|Degree elevation||11.30 ± 0.61||10.2–12.7|
|Mean ± SD||36.12 ± 3.37||20.30 ± 3.06||<0.001**|
|Benefit of angled scissors over straight scissors|
|Items||Mean ± SE||95% CI|
|Distance elevation||16.04 ± 0.61||14.8–17.3|
|Mean ± SD||47.32 ± 3.77||42.33 ± 3.26||<0.001**|
|Harm of angled scissors over straight scissors|
|Items||Mean ± SE||95% CI|
|Length elevation||5.45 ± 0.71||4.08–6.94|
Tab. 2. Difference between angled scissors and straight scissors groups regarding maternal pain.
|Present||1 (3.3%)||6 (20.0%)||0.049*|
|Absent||29 (96.7%)||24 (80.0%)|
|Benefit of angled scissors over straight scissors in avoiding injury|
|Rate in angled scissors group||96.7%||91.9% – 99.6%|
|Rate in straight scissors group||80.0%||77.6% – 91.2%|
|Rate elevation||16.7%||2.1% – 23.9%|
|Efficacy||17.3%||1.2% – 24.8%|
|Relative Rate||1.160||0.998 – 1.462|
|Number needed to treat||6||3.09 – 102.30|
Tab. 3. Obstetric anal sphincter injuries among the studied groups.
|Mean ± SD||2.23 ± 0.61||2.14 ± 0.61||^0.570||--|
|Range||1.0 – 4.0||1.0 – 4.0|
|Impaired healing||1 (3.3%)||3 (10.0%)||#0.329||0.33
(0.04 – 3.03)
|Wound infection||1 (3.3%)||3 (10.0%)||#0.329||0.33
(0.04 – 3.03)
Tab. 4. Maternal pain and complications at follow up among the studied groups.
|APGAR 1||Mean ± SD||7.57 ± 0.92||7.56 ± 0.82||^0.728|
|Range||6.0 – 9.0||6.0 – 9.0|
|APGAR 5||Mean ± SD||8.48 ± 0.82||8.47±0.82||^0.512|
|Range||7.0 – 10.0||7.0 – 10.0|
|Neonatal trauma (n, %)||0 (0.0%)||0 (0.0%)||--|
Tab. 5. Neonatal outcomes among the studied groups.
Our results interpretation and comparison with similar studies.
This is a prospective comparative study comparing the Angled scissors with the straight scissors with assisted forceps delivery. The mean episiotomy suture angle measured postpartum in our study with Angled scissors was (40.2 ± 2.2). This is similar to that observed by Freeman et al.,  it is less than that achieved by Patel and Ubale however, 36% of women in their cohort were parous and this would influence perineal distensibility . Our results are also comparable to El-Din et al.,  who found a post-delivery suture angle of 44 degrees (achieved by marking the perineum with gentian violet).
Post-delivery mean distance from midline in our study was (35.8 ± 3.3) in the angled scissors group while with the straight scissors, the distance was (19.9 ± 3.0) This is similar to that observed by Swant and Kumar who found that the post-delivery linear distance from caudal end of the sutured episiotomy to the anus was 15 mm more with the ANGLED scissors compared to straight scissors .
In our analysis, we also found that angled scissors episiotomies were longer. This is similar to that observed by Swant and Kumar who found that angled scissors episiotomies measured longer (47 mm versus 40 mm, P<0.0001) .
Obstetric anal sphincter injuries OASIS were significantly less frequent among angled scissors group than among straight scissors group. It was one in the angled scissors episiotomies compared to 8 patients in the straight scissors group. This is similar to that observed by Swant and Kumar, there were no OASIS cases in the angled scissors group versus one in the straight scissors group . But we had higher number of OSAIS, this could be attributed to the instrumental delivery.
No significant difference was detected between the angled scissors and straight scissors groups in terms of maternal pain and complications at follow-up.
Additionally, we discovered no discernible change in APGAR score and neonatal outcomes between the research and straight scissors groups.
Strength point of our studies is that it contains adequate no of patients and it is performed in 2 centers but its main weak point is lack of randomization due to difficulty in making randomization in both hospitals.
In clinical practice, not all the hospitals supply the angled scissors that is designed to episiotomy, the normal deliveries can pass smoothly with straight scissors episiotomy but in outlet or low forceps deliveries the incidence of OASIS is higher.
Further studies are needed to study effect of angled scissors in ventose and kiwi deliveries.
To sum up, the use of angled scissors during assisted forceps deliveries has resulted in a statistically significant decrease in OASIS.
Study approved by the ethical commitee of the hospitals mentioned above.
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.
The authors report there are no competing interests to declare
This study received no financial support.
(A) Study Design · (B) Data Collection . (C) Statistical Analysis · (D) Data Interpretation · (E) Manuscript Preparation · (F) Literature Search · (G) No Fund Collection
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