Gowri Dorairajan1
(1)
Obstetrics and Gynecology, JIPMER, Puducherry, India
There have been many occasions when a multigravida with neglected labour presented to the emergency room in shock with the clinical features of tachycardia (low volume pulse), hypotension, and severe pallor. The woman may not complain of much pain because the violent contractions have ceased. In a typical case, the abdominal examination would reveal free fluid (haemoperitoneum), superficial foetal parts, absent foetal heart sounds, and variable (usually mild) vaginal bleed. Vaginal examination in such a scenario would reveal recession of the presenting part or no foetal parts felt either through the os if it admits a finger or through the fornices.
Developed countries have phased out rupture of the uterus due to neglected and obstructed labour. Unfortunately, these maladies still happen in our and other developing countries [11–13]. These have distinctly come down over the last two decades with efficient referrals and emergency obstetric facilities made available at community health centres. It was very disheartening to read the article by Prajapati and co-authors [10]. The authors reported three cases on whom they performed a postmortem. All of them were reported to have difficult labour, and postmortem revealed haemorrhagic shock with ruptured uterus and foetus in the peritoneal cavity.
Such cases should be recognized early, and one must carry out the needful like resuscitation and definitive treatment with laparotomy promptly. If recognized early and treated appropriately, the maternal mortality due to ruptured uterus and haemorrhagic shock should be brought to zero.
Singh and Shrivastava [13] reported rate of rupture of 0.152 % in women without a uterine scar. In yet another study from Rohtak (North of India), Gupta and Nanda [7] reported that 52.6 % cases of rupture were due to neglect and obstructed labour.
Khooharo et al. [8] observed that the incidence of ruptured uterus was 20 % in obstructed labour. They studied 40 patients with obstructed labour and barring one woman who was a primigravida, all the other seven women who ruptured their uterus were multigravida. Rupture of the uterus following obstructed labour has high perinatal mortality. Fortunately, this kind of a typical case is very easy to recognize even by an undergraduate student.
However, a rupture of the uterus in a multigravida can have varied presentations.
3.1 Rupture in the Second Stage
I would like to narrate a few cases. A woman pregnant for the second time with a previous normal, uneventful delivery presented in labour. I examined her at admission. The vitals were normal. She was not anaemic. Abdomen revealed a singleton term foetus with moderate contractions. The foetal heart sound was 120 dropping to 100/min. On vaginal examination, she was fully dilated with vertex at +2 station and a normal pelvis. There was no caput or moulding. I admitted her and informed the sister to take her delivery immediately. The dropping foetal heart sound worried me. I got a call from the sister half an hour later that she has not delivered, and the foetal heart sound is no longer heard. I rushed to attend to her. She was stable. Pulse was 100/min. BP was 120/70 mm of Hg. There were no contractions, and the foetal heart sound was absent. On vaginal examination, the head had receded to 0 station. There was no bleeding from the vagina. When I inserted a urinary catheter, there was frank haematuria. I wheeled her for immediate laparotomy which confirmed a rent in the left lateral wall (Fig. 3.1) involving both the upper and lower segments. The rent had involved the bladder, and the foetus was lying in the peritoneal cavity. I had to resort to a hysterectomy. The bladder rent was repaired.
Fig. 3.1
Rupture of the lateral wall of the uterus
Unlike the bladder rents following obstructed labour or involving previous scars, in this case, the edges of the bladder rent did not seem to be oedematous or friable. On later questioning, she gave a history of curettage for a previous spontaneous abortion. I presume there must have been a low perforation with the bladder getting adhered to it. It is very important to understand that the uterus is likely to rupture in the second stage after going through the whole labour if there is a weak point in the lower segment. Xia and colleagues [20] reported two cases, one of whom had a scarring due to placenta accreta and the other without apparent cause. Both these cases also had manifested with foetal bradycardia before manifesting rupture. Foetal heart rate abnormalities were found to be the most frequent manifestation [6] among the 25 cases with complete rupture in a retrospective analysis of ruptures over 20 years. The gradual diminution of amplitude of uterine contraction followed by severe prolonged bradycardia has been described as staircase sign by Matsuo and colleagues [9].
The case emphasizes the need to monitor and be vigilant even in the second stage of a woman who appears to be a low-risk case in labour.
I would like to detail another case I had managed about 10 years back. The case was handed over to me in the labour room as a third gravida with previous two normal deliveries. She had been admitted half an hour earlier with term pregnancy in the second stage with foetal demise. There was no history of bleeding. She had been started on oxytocin drip as there had been no contractions observed at admission. When I examined the woman, she appeared peaceful and comfortable. Her pulse was 90/min. Blood pressure was 120/80 mm of Hg. She was mildly anaemic. Abdominal examination revealed term size uterus with expected foetal weight of 3 kg. The contour was well made out. There were no contractions. The foetal heart sound was absent. Vaginal examination revealed a fully dilated and effaced cervix. The vertex was at 0 station. There was no caput or moulding. There was no bleeding. The pelvis was normal gynaecoid. She did not have any pain. In fact, she requested me to do a caesarean as she had not delivered in spite of 1 h of being in the second stage. I reassured her and counselled for oxytocin drip and vaginal delivery. I continued the oxytocin drip. The patient’s condition remained the same. The labour had come to a standstill. Contractions failed to establish, so I took her up for a caesarean section as she refused any destructive operation. On opening the abdomen, I observed that the lower segment had completely given way with the shoulders presenting at the edges of the rupture. The foetal trunk and breech were still inside the upper segment. There was minimal haemoperitoneum. The shoulders had probably tamponade the ruptured edges (Fig. 3.2).
Fig. 3.2
Line diagram depicting tamponade by shoulders s on the edges of the ruptured lower segment LS preventing exsanguination
It indeed made me feel miserable to have missed rupture. In this case, foetal demise and the loss of uterine contractions in established labour especially in the second stage were the features signalling possible rupture. In the previously discussed case, the sequence of events happened right after admission, and the changing findings with the contractions ceasing, the station receding, and the foetal heart disappearing were clear features of rupture. Thus even though the woman is stable without any other features of rupture, these two important findings of cessation of contractions and foetal demise in labour in a multigravid woman may be the only clue for suspecting rupture especially when the previous record of the station of the presenting part is not available. I still vividly remember the name and face of the patient and her earnest request for caesarean. Fortunately, I did not try any instrumentation or destructive procedure. The adage that when a multiparous woman feels that something is not well with her in established labour, we need to heed to her, is so true for this case. There was no other cause for this rupture other than the fact that she was a multiparous woman.
3.2 Rupture Misdiagnosed as Antepartum Haemorrhage Due to Placenta Previa
I would like to narrate two cases that bring out a close differential diagnosis confusing the picture and delaying the diagnosis.
A woman in her third pregnancy presented at term pregnancy with bleeding from the vagina. It was the first episode of bleeding. She was in shock at admission. Abdominal examination, however, revealed a lax abdominal wall with a poor tone of the rectus muscle. The contour was made out. The foetal parts were not superficially palpable but were easily palpable. There were no uterine contractions. The duty resident made a diagnosis of placenta previa with intrauterine foetal demise. The patient was quickly resuscitated and wheeled for caesarean. At laparotomy it was realized that the uterus had ruptured, the foetus was in the amniotic sac with fluid pockets around it, and the back of the foetus was under the abdominal wall resulting in a false sign of maintained contour of the uterus. What was perceived as low-lying placenta on sonography was the retracted uterus. In this case, the definitive management was immediate laparotomy as she was in shock. So the exact preoperative diagnosis may be inconsequential.
I would like to narrate yet another interesting case we recently managed in our hospital. A woman pregnant for the third time, with previous two normal deliveries, was referred from a primary health centre as a case of suspected abruption. She was 32 weeks pregnant and complained of sudden onset painful bleeding followed by loss of foetal movements. She was not hypertensive. There was no history of trauma or previous fibroids. She had been transfused a pint of blood in the primary health centre 16 h before she came to our hospital. Her pregnancy was so far unsupervised. There was no history of prior caesarean/abortions/uterine procedures.
At admission to our hospital, her pulse was 100/min and blood pressure was 110/70 mm of Hg. She was moderately pale, ill-nourished, and asthenic. The admitting resident made a diagnosis of abruption because the uterus was 32 weeks size with normal contour and slight tenderness. The foetal heart sound was absent. The cervix was uneffaced and closed, and there was no bleeding observed. Urinary catheter revealed high-coloured but adequate urine. We transfused one more pint of whole blood as the baseline investigations revealed moderate anaemia with a haemoglobin of 6.5 g%. The coagulation profile and blood urea and creatinine were normal. Labour induction was started with 50 μg of misoprostol sublingually. The junior consultant reviewed the case and concurred with the clinical findings. The bedside sonography by the consultant revealed a foetus with signs of spalding, with adequate liquor around the foetus. The foetus was presenting as vertex high up. The placenta was found anterior, but a succenturiate lobe of the placenta was found to be overlying the os. There was no free fluid. The revised diagnosis was as placenta previa with foetal demise. The patient had not responded to labour induction. The case was discussed with me and I saw the woman nearly 36 h after admission. I observed that she was asthenic, ill-nourished, and not in pain. Her pulse had settled to 90/min. and BP was stable at 120/80. There was adequate urine output. Abdominal examination revealed a 32-week size relaxed uterus with absent foetal heart sounds. Vaginal examination revealed a closed cervix but no presenting part from the fornices. We discussed, and since she was stable with a macerated foetus, with placenta previa, with no further bleed, we took a calculated risk of extra-amniotic saline instillation after counselling and discussing with the woman. The same was performed uneventfully. She was under strict observation for any bleeding. Facilities for immediate caesarean section were kept ready in the case of bleeding. She remained status quo for the next 24 h. I must confess I was internally reflecting with the finding of no presenting part from the fornices gnawing at me, when in the middle of the night I woke up agonized when it dawned on me that we have missed ruptured uterus. I felt miserable. Laparotomy confirmed a longitudinal rupture of the anterior wall of the upper segment (Fig. 3.3).
Fig. 3.3
Longitudinal rupture of the anterior wall of the uterus with friable oedematous margins
The foetus was lying in the peritoneal cavity with intact membranes and amniotic fluid. The placenta was anterior and so was the back of the foetus. There was about 400 ml haemoperitoneum.
The case humbled me. Thinking back, I realized that the bias of admission diagnosis, the false appearance of preserved contour due to anterior back with intact amniotic sac and amniotic fluid around it, and the steadily settling pulse rate and stable blood pressure had misled me.
However, there were enough typical features. The presence of painful bleeding, moderate pallor, and inability to establish labour with inducing agents and the lack of presenting part from the fornices or through the cervical os are glaring enough to suggest rupture. The woman was not in shock possibly due to retraction of the uterine margins which were no longer bleeding briskly inside. These cases may get misdiagnosed as antepartum haemorrhage due to low-lying placenta or abruption placenta at the first presentation.
I would like to bring out this important take-home message and an important component of the checklist. I would like to emphasize that whenever one does an abdominal sonography for cases of antepartum haemorrhage, one should look at the continuity of the uterus from the cervix preferably with some fluid in the urinary bladder (which we all ignored with the patient on a continuous bladder drainage). As a checklist, the continuity of the myometrium should be traced till the fundus and posteriorly to rule out rupture in every case of antepartum haemorrhage. In this case, once again it was the retracted ruptured uterus that was mistaken for a placental lobe overlying the cervix (Fig. 3.4).
Fig. 3.4
Schematic line diagram showing the retracted uterus U mistaken as the placental lobe. The extruded foetus F is in the intact amniotic cavity with amniotic fluid A. The placenta P is anterior
This lady must have ruptured when she initially presented with bleeding to the health centre. The omental reaction and the oedematous and friable edges of the ruptured uterus put in vain all efforts to repair resulting in cut through and more bleed, and after all the struggle at repair, we decided to do a subtotal hysterectomy. The procedure and recovery were uneventful. It is therefore very important to have a high index of suspicion of rupture in every case with antepartum haemorrhage. The reason for rupture, in this case, remains unexplained.
3.3 Rupture Due to Misdiagnosed Malpresentation
I would like to narrate one more case which I had managed as a registrar. A woman was admitted in her third pregnancy at 37 weeks in early labour with foetal demise. She had no comorbidities. She was in spontaneous labour. She had leaked amniotic fluid from the vagina about 3 h before presenting. There was a loss of foetal movements. The admitting registrar had made a diagnosis of a breech presentation with cord prolapse with absent pulsations. The woman progressed spontaneously in labour, and when I took over the labour room, she was getting good contractions and she was fully dilated with the feet of the baby in the vagina. There was no augmentation of labour. She was not anaemic. The uterus was regularly acting. After about 1 h when she did not expel the foetus spontaneously, I decided to deliver her. The feet were in the vagina, so I gave traction to the same and uneventfully delivered the dead foetus as assisted breech delivery. It was a 2 kg foetus. What followed was a nightmare. There was postpartum haemorrhage, and when I examined the vagina, it was intact, but there was a cervical tear on the left side. It was pretty deep. I tried reaching the apex. I gave traction after suturing the highest reachable level but still could not reach the apex. I informed the consultant and arranged blood and shifted her for proceeding under general anaesthesia. In the last 1 h of struggle, her pulse had risen to 120/min and systolic BP had fallen to 90 mm of Hg. Under anaesthesia, the consultant did a vaginal exam and suspected rupture. We proceeded with laparotomy. There was rent in the lateral wall of the uterus. The stay suture taken from below was seen, and the cervical tear was continuous with the rent on the uterus. A hysterectomy was carried out. The patient recovered from the procedure well. Fortunately, there was no colporrhexis. The audit with the consultant the next day was an unforgettable experience. The notes of the admitting resident revealed that the vagina was 2 cm dilated with feet, cord, and the head tipped to the side. There were no cord pulsations. The findings clearly meant that a transverse lie had been missed. Though the labour progressed spontaneously till full dilation and the feet got delivered from the cervix into the vagina, it was truly not breech throughout labour. The lower segment must have been in impending rupture when the feet were pulled in an attempt to deliver the baby as breech. The uterus would have ruptured as the delivery was being attempted. The learning point here is that one has to be very careful while interpreting the vaginal examination findings especially when it is a compound presentation with a cord loop. I just wondered whether an intrapartum scan would have revealed that it is a transverse lie. Of course, those days (nearly 20 years back) we never had any scan facilities in the labour room. The lie may sometimes get missed because the liquor has got drained and the pelvic grip does not appear empty. I have illustrated the above case in detail though it is a known fact that labour in a transverse lie can cause rupture to bring out how subtly the detection of transverse lie can get missed especially in a labour room with high turnover and changing doctors in shift duties.
3.4 Rupture Due to Trauma of Friable Lower Segment During Caesarean Section
I faced a once in a lifetime situation about 12 years back. The registrar operating in the emergency operation theatre called me. A second gravida admitted with obstructed labour had been taken up for caesarean section. The resident had carried out lower segment caesarean section. The baby was born alive but asphyxiated. The registrar called because he could not identify the edges of the incision and had suspected extension of the lower segment incision. The baby delivery was difficult. The woman had already bled quite a lot. When I joined in, what I observed was unimaginable. The incision on the lower segment had extended all around detaching the uterus completely from the vagina at the fornix. Whereas the upper edge of the incision was seen, the lower flap was nowhere identifiable. To orient myself I had to guide a finger from the vagina below. The finger was seen from above, but the upper segment was no way connected. The cervix or lower segment was not identifiable. I had to resort to hysterectomy and closure of the vault (Fig. 3.5). It was once in a lifetime finding. The birth canal with the merged cervix and vagina must have got avulsed from the attachment to the uterocervix. It might have been in the process of impending rupture, and the caesarean incision and extraction of the baby completely disrupted the attachment of the fornix all around.
Fig. 3.5
Schematic diagram showing upper segment completely detached from the vagina
I guess the incision for the caesarean must have been low on the fused vagino-cervix (part of the birth canal in the second stage). It might be a wise idea to keep the incision in the lower segment slightly higher to avoid caesarean through colpotomy in women subjected to caesarean section late in the second stage of labour.
Thus, a multiparous woman would rupture when there is an obstruction to labour or when there is a transverse lie. A spontaneous rupture in the absence of these can also happen in a multiparous woman as with increasing parity few of the myometrial fibres get replaced with scar tissue. Rupture can occur in grand multiparous woman, even in the absence of labour, as has been reported by Guèye et al. [5].
In an interesting study on mice, Skurupiy and colleagues [15] observed that after repeated pregnancies the involution of myometrium gets delayed. There is hypertrophy of myometrium against poor vascularization, thereby resulting in the destruction of myocytes. The same authors [16] further confirmed that involution after third pregnancy takes longer to remove the necrosed myometrium.
3.5 Rupture of Unscarred Uterus from Literature
Rare causes of ruptured uterus in unscarred uterus have been described in the literature. Authors [14] have reported rupture of the fundus of the uterus following road traffic accident that caused foetal death and merited hysterectomy.
Sun et al. [17] reported the case of a third gravida. She had presented with upper abdominal pain at 17 weeks and later evolved into acute haemoperitoneum and shock. Laparotomy diagnosed rupture of the fundus of the uterus with intraperitoneal extrusion of the foetus. No cause could be attributed to the rupture. Various aetiologies for ruptured uterus including cocaine abuse have been reported in the literature as a cause of the uterine rupture [1]. An extremely interesting case was reported by Wang and colleagues [19]. The woman had cornual rupture but with live intact foetus in the uterus at 21 weeks. The same was managed by suturing of the rent and continuing the pregnancy. Caesarean delivery was later performed at 33 weeks of pregnancy.
Cuellar [3] reported a woman who was administered 800 μg of misoprostol for second-trimester abortion. She had previous two normal deliveries and had no scar. She developed a linear tear in the uterus which was diagnosed and sutured at laparotomy.
Syed and colleagues [18] reported a fifth gravid woman with missed abortion in the second trimester. Abortion was induced with 400 μg of misoprostol. After four doses she did not abort and so misoprostol had been repeated. She developed continuous pain. At laparotomy, she was found to have a broad ligament hematoma. On opening the same, there was a tear in the lateral wall.
In a recently published article [11], the authors observed the rate of rupture in an unscarred uterus to be 0.28 %. This study was from a large tertiary care hospital catering to women of low socioeconomic status. They observed that only 48.6 % of cases with ruptured uterus had a previous caesarean scar. 24.3 % had obstructed labour. 85.1 % had a complete rupture. Rupture involved the anterior wall in 69 %. 10.8 % had colporrhexis, and 6.8 % had associated bladder injury. A hysterectomy was necessary for 61 %. Internal iliac ligation had been performed in 2.7 % of cases. Perinatal mortality was 90.5 %, whereas maternal death occurred in 13.5 % cases. Rizwan and co-authors [12] observed similar results in their study over a 2-year period in Pakistan. They observed that prolonged neglected obstructed labour was responsible for 53.33 % of the ruptured uterus.
In a 2-year audit of ruptured uterus in a large tertiary care centre in Delhi, India, the authors [2] found that 12.6 % were in the unscarred uterus (0.04 % of the deliveries). Half of these were due to obstructed labour. Uterine malformations, administration of oxytocics, and instrumental deliveries were the other reasons for rupture in unscarred uterus.
Gibbins et al. [4] compared the ruptures in the unscarred uterus with those in the scarred uterus. They observed that the rupture in the unscarred uterus was more likely to occur in a multiparous woman and with oxytocin administration. They further observed that the maternal morbidity, hysterectomy, and perinatal mortality are significantly higher with rupture in unscarred uterus compared to rupture among women with previous caesarean section.
Thus, ruptures in an apparently unscarred uterus are usually seen in a multigravida. It can happen due to obstructed labour because of a big baby, a deflexed head with posterior position, and transverse lie in labour. Most of these ruptures would involve the lateral wall. The rupture could start in the lower segment but would invariably involve the uterine arteries. Cases with rupture due to neglected or prolonged or obstructed labour in a multiparous pregnant woman are more likely to involve the lateral wall. They are more likely to require a hysterectomy and have higher maternal mortality and perinatal deaths.
Box 3.1 summarizes the features associated with rupture of the unscarred uterus.
Box 3.1 Features of Rupture in Unscarred Uterus
· Haemorrhagic shock with haemoperitoneum in labour
· Loss of uterine contour and superficial foetal parts and foetal demise
· Bleeding in the third or late second trimester associated with pain and loss of foetal movements
· Cessation of uterine contractions in labour with or without bleeding from the vagina
· Profound foetal bradycardia invariably resulting in foetal demise in labour
· Recession of presenting part
· Inability to feel foetal parts through the cervix
· Brisk postpartum haemorrhage
· Intrapartum or postpartum haematuria
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