Key words
Caesarean section - section modification - Vejnović method
Schlüsselwörter
Sectio caesarea - Sectio-Modifikation - Vejnović-Methode
Introduction
Caesarean section is one of the most commonly performed operations for women all over
the world. Until the middle of the last century caesarean section rates in Europe
rarely exceeded 3–5 % [1]. Currently around every 3rd baby (31.3 % on average) born in German hospitals is
delivered by caesarean section [2], [3], [4].
The increase in the numbers of caesarean sections performed has been ascribed to the
increased range of indications, increased numbers of preterm deliveries and increased
legal disputes. The most important indications for caesarean section include breech
presentation, protracted birth including failure to progress in labour, incipient
intrauterine hypoxia and previous C-section [5], [6], [7], [8]. In the past few years it appears that the rate of elective C-sections has also
risen, but no reliable figures are available on this point. It is also assumed that
improvements in C-section techniques resulting in decreased maternal and foetal morbidity
and mortality have also contributed to a more general use of this method of delivery
[9], [10]. Over the past few decades the “classic” Pfannenstiel technique has been
replaced, first by the Joel-Cohen method and then by the “gentle” Misgav-Ladach technique
[11], [12], [13]. The changes in operative techniques have resulted in shorter operating times, less
loss of blood, reduced tissue trauma and a greater patient satisfaction [14], [15], [16].
Other modifications to the C-section method were developed at the beginning of 2000
at the University of Novi Sad (Serbia) and have been retrospectively compared with
the classic C-section technique [17]. A Doerfler C-section was done in 600 patients [18] and 5648 patients were operated using the newly modified method. A comparison with
the classic caesarean section method showed that the modified technique reduced blood
loss (342 vs. 495 ml) and postoperative pain and shortened the time required for surgery
(average time: 12 vs. 40 min). The in-hospital stay was also significantly shorter
(3.3 vs. 6.7 days) [17]. Overall, intraoperative and postoperative morbidity were significantly reduced
with the modified technique.
We describe this technique in detail below and present the first data of a prospective
comparative study comparing the “classic” C-section method and the modified technique.
Patients and Methods
Study design
The prospective study was carried out between 1 May 2008 and 1 March 2009 in the Department
for Gynaecology and Obstetrics of the Clinical Centre Vojvodina in Novi Sad, Serbia.
Inclusion criteria were primiparity and planned elective C-section together with informed
consent signed by the patient. Patients were randomised into one of two groups by
computer randomisation. A total of 122 patients were investigated in the study; the
new C-section method was used in 72 patients (59.1 %) (Group A) while the classic
Doerfler C-section method was used in 50 patients (40.9 %) (Group B). Exclusion criteria
were emergency C-section for various reasons, refusal of patient consent to take part
in the study and incomplete follow-up data.
The surgeon was only informed a short time prior to the operation which technique
would be used. On the day of discharge patients were informed which arm of the study
they had been randomised to. Operations were performed under local or spinal anaesthesia.
The time required for surgery, duration of inpatient stay and blood loss were recorded
for comparison. The operating time was measured from starting the skin incision at
the start of the operation to completion of skin suturing at the end of the operation.
Blood loss was measured using a suction device which suctioned only blood and not
amniotic fluid. Blood loss was also measured indirectly through the determination
of preoperative and postoperative Hb levels. A total of 10 surgeons were involved
in the study, half of them operated the women using the classic method and the other
half used the modified technique. All surgeons had performed at least 30 C-sections
using their chosen method prior to taking part in
the study. The number of patients of each group operated on by each surgeon was relatively
balanced and evenly distributed. Each surgeon operated on at least 10 patients.
Postoperative clinical follow-up was done at regular intervals; laboratory tests were
done as needed. Postoperatively, scar length, local reddening, swelling, seroma or
haematoma formation and pain in the area around the scar were evaluated. Patient satisfaction
was also investigated.
Comparison of Classic Caesarean Section with New Operative Technique
Comparison of Classic Caesarean Section with New Operative Technique
Description of the classic operative technique
The skin incision in the classic C-section technique is done as a horizontal Pfannenstiel
incision 2 cm above the pubic symphysis; subcutaneous adipose tissue and the abdominal
fascia are also sharply dissected using a scalpel and the aponeurosis of the transverse
abdominal muscles is detached from the straight abdominal muscles. The rectus abdominis
muscles are then pushed apart. This is followed by cranio-caudal incision of the peritoneum.
The peritoneum is severed from the front uterine wall and pushed away caudally. In
the classic C-section method the uterine wall is completely dissected using a scalpel,
and the incision is then extended manually in a slight horizontal curve. The child
is delivered manually after opening the amniotic sac. After determining the neonatal
pH-value, the placenta is removed by hand. Curettage of the uterus is done if there
is any suspicion that remnants of the placenta have been retained. Depending on the
extent of cervical dilation,
manual cervical dilatation or dilatation using Hegar pins is done to a width of around
3 cm. The uterus is closed using continuous or interrupted sutures. The peritoneum
and the musculature are sutured with continuous or interrupted sutures. The fascia
is closed as usual with a continuous suture. Finally the skin incision is closed with
intracutaneous continuous sutures.
Description of the new operative technique
Opening the abdomen (abdominotomy)
The site for the skin incision is selected by gently pressing the abdominal wall caudally.
The incision is then done along the skin fold created by this gentle pressure ([Fig. 1 a]) at approximately 5 cm above the pubic symphysis. The initial length of the incision
is approx. 6–7 cm. Later during the operation the incision is adapted to the circumference
of the babyʼs head (fronto-occipital diameter) or the breech presentation. This can
be achieved without difficulty if the skin is incised precisely along the skin fold.
The abdominal fascia are then sharply severed with a scalpel above the pyramidalis
muscles ([Fig. 1 b]). The abdomen is opened at the linea alba through traction on and dissection of
the fascia and access is subsequently enlarged through vertical and transversal traction
and blunt dissection.
Fig. 1 a to d Skin incision, uterotomy and delivery of the baby. a The skin incision is done along the skin folds and b the fascia are dissected above pyramidalis muscles. c The uterotomy is done using blunt forceps and scissors. d The baby is “born” by expanding the uterine wound using the fingertips to cranially
push the edges of the wound (arrows pointing cranially) over the babyʼs head like
a collar and exerting pressure on the uterine fundus (from [12]). The pressure on the fundus moves the babyʼs head in a caudal direction (s. arrows).
Uterotomy
After incising (approx. 2 cm) the uterine serosa 2 cm above the uterovesical fold,
gentle pressure is used to introduce a long anatomical forceps into the uterine cavity
at the level of the isthmic cervical segment at an oblique angle of approx. 30° past
the foetal head or breech presentation ([Fig. 1 c]). Using scissors positioned between the two arms of the forceps, the uterine wall
is incised along a length of 5 to 6 cm and bluntly expanded manually.
Delivery of the baby
The lower pole of the presenting part of the foetus is visible in the uterine opening
and is rotated into position. In the second phase the presenting part is “born” by
pushing the upper (“front”) and lower (“back”) uterine wound using the fingers of
the left hand cranially over the foetal presentation ([Fig. 1 d]). The “birth” is assisted by pressure exerted on the uterine fundus. The uterotomy
and the skin incision can be bluntly extended (digital manoeuvre) to adapt the incision
to the circumference of the foetal head. The right hand of the surgeon or assistant
is used to “press the baby out” of the uterus by pressing on the uterine fundus. No
wound retractors (i.e. no Fritsch or Roux retractors) are required during delivery
of the baby as skin elasticity is sufficient.
After delivery of the baby and clamping of the cord, a piece of the umbilical cord
between two clamps is removed to determine the neonatal pH-value, and the placenta
is removed using cord traction (traction using the remaining Pean clamp) and pressure
on the fundus. If the placenta is complete, digital exploration of the uterine cavity
is sufficient. If there is a suspicion that part of the placenta has been retained,
curettage of the uterine cavity is done using a large blunt curette. Depending on
the extent of cervical dilation, manual cervical dilatation or dilatation using Hegar
pins is done to a width of around 3 cm.
Uterine sutures
The uterine wall is closed using 2 sutures starting from the middle of the uterotomy
([Fig. 2]). The 1st suture is placed 3–4 cm medially from the anatomical corner of the wound.
Traction on the suture thread is used to properly approximate the corner of the wound
and the wound is closed using one or two transfixing sutures. The same thread is then
used to create 2–4 continuous sutures and the ends of the suture threads are knotted
and left long ([Fig. 2 a]). Using a second suture thread the contralateral side is closed analogously ([Fig. 2 b]). The middle of the uterus incision which is still open is then completely closed
using one of the two threads to create a continuous line of sutures ([Fig. 2 c]). The wound is then shortened further by alternately knotting the two ends of the
suture threads, burying the suture ([Fig. 2 d]).
Fig. 2 a to d Uterine suture technique. The uterus is closed by 2 sutures starting from either
end of the wound. a The first suture stitch is placed slightly medially from the anatomical corner of
the wound. The same suture thread is used to make 2–4 more continuous sutures and
the ends of the suture thread are knotted. b Analogously a second suture thread is used to close the uterine wall starting from
the other side. c Both sutures are knotted in the middle and d subsequently the suture is buried by knotting the suture threads (from [12]).
Closure of the peritoneum and the fascia
After inspecting both adnexa, the peritoneum is placed on the front wall of the uterus.
The peritoneum is not sutured. The fascia is closed as usual using a continuous suture.
Skin suture
The skin is closed using intracutaneous continuous sutures starting and ending approx.
2 cm medial to the corners of the wound ([Abb. 3]). This modification permits natural drainage of wound secretions and blood. After
disinfection, a large compress is placed on the wound. Although the subcutaneous adipose
tissue will be free of blood at the end of the operation the compress will typically
be soaked with blood after 2–3 hours and have to be replaced. Stitches are removed
between the 8th and the 10th postoperative day.
Fig. 3 a and b Skin suture. a The skin is closed using a continuous suture but both ends are left open for approx.
2 cm. b Schematic representation of the skin incision (from [12]).
Instruments required
A not unimportant aspect of this modified C-section technique is the low number of
instruments required, which results in a considerable reduction of costs. The following
instruments are required: scalpel, Kocher forceps, 2 Pean clamps, a long anatomical
forceps, long straight scissors, needle holder. Depending on the indication, obstetrical
Hegar pins for cervical dilatation and a large blunt curette for curettage of the
uterine cavity may be used. Both C-section techniques are described in [Table 1].
Table 1 Differences between the classic and modified the procedure.
Procedure
|
Vejnovic modification
|
Classic caesarean section
|
Skin incision
|
Joel-Cohen
|
Pfannenstiel
|
Incision of subcutaneous tissue
|
in the middle along a length of 3 cm
|
along the full length
|
Incision of the fascia
|
in the middle with minimal severing of the musculature
|
along the full length with severing of the musculature
|
Opening of the peritoneum
|
in the middle, blunt dissection, with minimal severing of the musculature
|
along the full length, sharp, bladder is pushed to one side
|
Uterotomy
|
superficial incision of the uterine serosa (scalpel), blunt introduction of forceps,
horizontal expansion of incision using scissors
|
incision through all layers of the uterus using a scalpel, manual horizontal expansion
|
Placenta extraction
|
cord traction
|
manual extraction
|
Uterine suture
|
buried, short suture
|
continuous, long suture
|
Peritoneal suture
|
none
|
continuous
|
Myosuture
|
none
|
interrupted sutures
|
Subcutaneous tissue
|
none
|
interrupted sutures
|
Skin suture
|
intracutaneous, continuous, open at either end
|
intracutaneous, continuous
|
Pain score
The patientʼs subjective pain sensation was assessed using the visual analogue pain
scale. Pain intensity was recorded daily by the patient, with 0 representing no pain
and 9 standing for worst possible pain. The pain intensity was recorded using a score:
0 no pain; 1–3 slight pain; 4–6 moderate to severe pain; 7–9 very severe pain.
Statistical evaluation
Data were obtained from questionnaires completed by the patients and from medical
records (operation protocol, postoperative follow-up etc.). The data was then encoded
and sent to a specially developed online database. The algorithm was subsequently
additionally verified and validated (logic control). Basic descriptive methods were
used for statistical analysis of the data. Absolute and relative figures, mean, standard
deviation and ranges were calculated.
Statistical calculations were done using SPSS 18 (SPSS, Chicago, IL, USA). The correlation
between C-section technique and clinical parameters was analysed using χ2 test and Fisherʼs exact test. Independent samples were analysed using the non-parametric
Mann-Whitney U-test. Values < 0.05 were considered statistically significant.
Results
The mean age was statistically similar in both groups: 29.6 years for Group A and
28.7 for Group B ([Table 2]). There were no statistically significant differences between the two groups with
regard to body mass index (BMI) or co-morbidities (e.g. diabetes mellitus, preoperative
anaemia, etc.). A comparison with the classic C-section method showed that with the
modified C-section technique the inpatient stay, particularly the postoperative in-hospital
stay, could be distinctly reduced ([Table 2]). The comparison shows a clear decrease in blood loss (p = 0.013) and a reduction
in operating times (p < 0.001). The mean loss of blood was 471 ml in Group A and 561 ml
in Group B ([Table 2]). The mean operating time in Group A was 10 min less than the mean operating time
for Group B (20.6 vs. 30.7 min).
Table 2 Patient age, in-hospital stay, duration of surgery and blood loss in both study groups.
|
Group A
|
Group B
|
|
Parameter
|
n = 72
|
n = 50
|
p-value
|
Age (years)
|
29.6
|
28.7
|
0.350
|
Inpatient stay (days)
|
5.56
|
6.08
|
0.018
|
Duration of surgery (minutes)
|
20.6
|
30.7
|
< 0.001
|
Blood loss (ml)
|
471
|
561
|
0.013
|
In addition, other outcomes such as scar length, skin reddening, formation of seroma
and haematoma and administration of antibiotics were analysed in relation to the chosen
surgical technique. The patients operated on using the modified technique reported
significantly less pain in the first 4 days postoperatively ([Table 3], p < 0.001). The average length of the scar in Group A was shorter (12.6 cm) compared
to the length of the scar in the control group (14.1 cm). Fewer incidences of reddening
and swelling were noted in Group A compared to patients in Group B ([Table 3]). There were no differences between groups with regard to seroma and haematoma formation,
skin dehiscence, inflammation or fever. A total 68 of 72 patients (94.4 %) in Group
A and only 34 of 50 patients (68 %) in Group B reported that they were very satisfied
with the C-section scar and this difference was statistically significant
(p < 0.001).
Table 3 Complications in both study groups.
|
Group A
|
Group B
|
|
Parameter
|
n = 72
|
n = 50
|
p-value
|
Pain (subjective)
|
Score
|
Score
|
< 0.001
|
|
2.89
|
4.1
|
|
|
2.22
|
2.96
|
|
|
0.71
|
1.18
|
|
|
0.06
|
0.3
|
|
Length of scar (skin)
|
12.6 cm
|
14.1 cm
|
< 0.001
|
Fever
|
2.8 %
|
4 %
|
1.000
|
Wound healing
|
|
|
|
|
13.9 %
|
32 %
|
0.029
|
|
2.8 %
|
14 %
|
0.048
|
|
1.4 %
|
0
|
1.000
|
|
0 %
|
2 %
|
0.854
|
|
4.2 %
|
8 %
|
0.617
|
Discussion
The operative technique presented here represents a further development of the so-called
“gentle” Misgav-Ladach C-section technique, which is already very popular all over
the world as the optimal method for caesarean section [13]. Use of the modified method was introduced in the University Gynaecological Clinic
of Novi Sad in Serbia in 2000 and it has been used there ever since [17]. Since 3 years it has also been used very successfully in the University Gynaecological
Clinic Magdeburg. The aim of the modifications was to reduce tissue trauma and minimise
perioperative morbidity. These basic aims of the modified method are already discernable
when performing the skin incision. In the horizontal Pfannenstiel incision and the
Misgav-Ladach C-section the skin is incised 2 cm above the pubic symphysis or 2 cm
below the linea interspinalis [11], [13]. The incision is
done using a scalpel along a length of 10–15 cm. In the Vejnovic modification, the
skin is incised along the skin folds which initially results in a relatively small
incision. The incision is later bluntly expanded depending on the circumference of
the babyʼs head and is thus adapted to fit the circumstances. This creates a scar
with an optimal length and generally with a very good cosmesis because it is not very
visible in the skin folds.
The fascia are initially incised and the incision is then expanded manually (bluntly).
Caudally they are no longer severed from the pyramidalis muscles. The fascia incision
can also be adapted to the circumference of the babyʼs head during delivery of the
baby. In contrast to classic methods and analogously to the Misgav-Ladach technique
the peritoneum is opened bluntly and horizontally [11], [12], [13]. This helps prevent injury to the bladder and the vasculature and excessive bleeding.
The most important modifications are related to the uterotomy and its closure. With
this uterotomy technique, after incising the uterine serosa with a scalpel, long anatomical
forceps are introduced through the uterus wall into the uterine cavity. By introducing
the forceps obliquely past the babyʼs head, it is possible to avoid injuries to the
babyʼs skin. In the classic C-section the uterine wall is completely incised, which
can occasionally (e.g. if the amnion has already ruptured and the amniotic fluid is
no longer present or if there is increased bleeding because the placenta is on the
anterior uterine wall) result in cuts to the babyʼs skin. In the Vejnovic modification
the uterotomy is incised using scissors between the arms of the forceps and is then
extended bluntly. The uterotomy is “adapted” to the circumference of the babyʼs head
when the head is delivered. The vertical cut using scissors through all the uterine
wall layers results in a better adaptation of
the two wound edges of the uterotomy, which may otherwise not always occur if they
are simply bluntly “torn apart”. Closure of the uterine wall is done in a single layer
as with the Misgav-Ladach method, but there are a few differences. Thus, the uterine
suture is started approx. 3 cm from both corners of the wound and suturing is then
continued laterally. Traction on the suture thread gives an optimal view of the wound
edges. Knotting the different suture threads together reduces the size of the uterotomy
to around 50 % and buries the suture. This helps avoid additional secondary sutures
to treat bleeding from the uterine wall. The resulting scar is short with a relatively
thick myometrium and very stable. This is done with the aim of decreasing the incidence
of uterine rupture and suture dehiscence and minimising placental disorders in subsequent
pregnancies. While complete uterine rupture after a classic or Misgav-Ladach C-section
is rare (0.7 % after one and 0.9 %
after repeated C-section deliveries, cf. [19], [20]), the length of the uterotomy scar, measured ultrasonographically after a C-section,
appears to correlate with suture dehiscence during birth. It has been shown that suture
dehiscence or uterine rupture occurs in 5.3 % of cases with smaller scars compared
to 42.9 % with large scars [21]. Whether this suture technique could be an important factor in preventing uterine
rupture in subsequent pregnancies will only be clear with longer follow-up times.
As more than 7000 C-sections have been carried out using the new technique at the
University Gynaecological Clinics of Novi Sad and Magdeburg, the data obtained could
offer a good basis to answer such questions.
In contrast to other C-section techniques, in the modified C-section technique presented
here the fascia and skin incisions are adapted to the size of the babyʼs head or breech
position by manually pushing back the anterior and posterior uterine walls. The baby
is literally “born” through pressure exerted on the uterine fundus. It is conceivable
that this compression pressure could help expel amniotic fluid from the lungs as occurs
in vaginal births. Only a prospective study in a defined patient collective could
show whether there are fewer respiratory adjustment disorders with the method described
here compared to classic caesarean sections.
The fascia is closed using a continuous suture as is done in other C-section techniques.
The two ends of the skin suture are left 2 cm open. This modification creates “natural
drainage” and helps prevent haematomas and seromas. The cosmesis with this method
is very good as the initially open edges of the wound close within a few hours and
no fluid-filled cavities remain subcutaneously.
Conclusion
C-sections are the most common obstetrical operations. In Germany around one third
or all children are now delivered by caesarean section. This amounts to approximately
200 000 C-sections annually. The “gentle” Misgav-Ladach C-section technique is currently
the standard procedure used in Germany. The modification of the caesarean section
technique described here changes the position and length of the skin incision, avoids
injury to the baby by the blunt introduction of forceps into the uterus and involves
a different type of closure of the uterine wall. This new type of closure should help
reduce complications in subsequent pregnancies. The first promising results are expected
from prospective studies in a defined patient collective.