Negative sliding sign by ultrasound in repeat cesarean section predicts presence of severe intrabdominal adhesions

Photo courtesy: YouTube video clip by Green Journal

A negative sliding sign by ultrasonography (USG) in patients with previous cesarean section helps alert the surgeon to expect massive intraabdominal adhesions, difficult repeat cesarean section and need of blood transfusion during surgery reports the results of a prospective observational study published ahead of print in the February issue of Journal Obstetrics and Gynecology.

Postoperative adhesion formation is quite prevalent after an abdominal or pelvic surgery and any method which can predict the existence of such adhesion could optimize the outcome of current surgery.

Real-time ultrasound-based technique of ‘slide test’ is the non-invasive way of detecting pelvic and intrabdominal adhesions preoperatively. The test measures the relative motion between abdominal and uterine wall.

The researchers recruited 370 women with previous cesarean section. The women underwent transabdominal sonography and a video-clip was recorded at deep inspiration in sagittal plane lateral to the midline.

The findings of preoperative ultrasonography were correlated with adhesions found during surgery by surgeons who were not aware about the preop USG findings.

Statistical analysis of these findings showed that when less or no movement was detected between the uterus and abdominal wall (negative ‘slide test’), it correctly identified patients with severe adhesion in 56% of cases (sensitivity 56%, 95% CI 35–76). It also predicted absence of severe adhesions correctly in 95% of patients (specificity 95%, 95% CI 93–97).

When the USG findings was combined with history of adhesions in previous surgery, severe adhesions were correctly predicted in 64% of patients and absence of adhesions was predicted in 94% of patients.

The surgeons noted a longer delivery time and significant blood loss in patients with negative sliding sign.

Thus, it was seen that ‘slide test’ is a simple, reliable and non-invasive screening test in repeat cesarean cases to predict technical difficulty during surgery.

Here is a short video of visceral slide test from video gallery of Journal Obstetrics and Gynecology.

This short video clip explains the equipment needed, how to perform, and how to interpret the visceral slide test. An example of a normal test and an abnormal ultrasound visceral slide test are illustrated, including a laparoscopic view of the patient with an abnormal test.

Video courtesy of Erica C. Dun, MD, MPH.

 Abstract 

A C-section rate of approximately 19 percent seems to be ideal for the health of both women and newborns.

All generalization are false including the recent statement by India’s Union women and Child Development Minister about bringing down the C-section rate to 10%. The minister recently asked the health minister to issue a mandate to all the hospitals displaying the C-section rates. She took this action in response to a Change.org petition against hospitals and doctors profiteering by pushing women towards surgical deliveries instead of natural vaginal birth.

The petition has received 1.3 lakh signatures so far, a number that is not much looking at the total population of the country.

"We have entered into an area, very sorry to say, in the last 20 years, where doctors care more about money than about patients' health. We would like the hospitals to display data on how many cesarean section deliveries they have done," said the Minister.

"The normal Cesarean delivery rate in a country would not be more than 10 percent, because it is usually done as a last resort. In this country, it is extremely high because it brings the doctor more money," she further added.

Well, you cannot generalize and mandate a uniform C-section rate for all the hospitals in all the states across country. It all depends upon the healthcare infrastructure, geographical location, access to prenatal care and surgical expertise and the needs of individual woman.

Pointing a finger at the obstetrician and asking her to stop doing C-section is like treating a symptom instead of going into the root of problem. A hospital can have a C-section rate as high as 70% if it a tertiary care high risk hospital.

A review of trends around the world shows that currently about 18.6% of births take place by Cesarean section.  The rates vary from as low as 2% to as high as 50%. In U.S.A, about 1.3 million babies are delivered by Cesarean every year, which roughly equals to every 1 in every 3 children born in US(33%).

The WHO recommends that the ‘ideal’ rate of C-section for optimum maternal and fetal outcome should be around 10-15%.This was  based on the  observation that some countries with the lowest perinatal mortality rates had cesarean delivery rates that were less than 10 per 100 live births. The study also has insufficient data and relied upon average C-section rate from multiple previous year.

However, new study recently examined the relationship between C-section rates and maternal and neonatal mortality in 194 countries around the globe concluded that C-section rate up to 19 percent is associated with lower maternal and neonatal outcome. C-section delivery rates above 19 percent showed no further improvement in maternal and neonatal mortality rates.[1] Researchers used mathematical modeling to impute C-section rates for countries where data was missing and to account for other contributing factors such as health expenditure.

Latin America and the Caribbean region has the highest CS rates (40.5%) while some countries in Africa have the lowest (7%). Brazil occupies the top slot with a rate that exceeds 50% (55.6%).

The  study  found out that in countries with very low C-section rate, people did not have access to basic healthcare and surgical facilities resulting in high maternal and neonatal morbidity and mortality. In fact, a study by WHO concluded that in countries with C-section rate < 10%, there is an additional need for 0.8 – 3.2 million CS every year to improve maternal and neonatal mortality and morbidity. [2]

Dr. Thomas Weiser, an assistant professor of surgery at Stanford School of Medicine says “As countries increase the number of C-sections they provide, mortality goes down— but only to a point, when the C-section rate tops 19 percent, benefits for maternal and infant health plateau.

Increasing C-section rates in recent years are due to modern technology of continuous FHS monitoring in labor room which is a two-way sword, practicing defensive medicine, rise in on-demand C-sections beside other maternal and perinatal factors that come into play.

According to ACOG " Safe reduction of the rate of primary cesarean deliveries, is the only way to  lower  the repeat  cesarean section rate and total cesarean rate."

To conclude, it is impossible to form a policy regarding relationship between delivery methods and birth outcomes. Each case must be decided taking into consideration social, medical, obstetrical and healthcare factors.

Our goal as an obstetrician should be to see that every woman who needs a C-section should get one and every woman who does not need a C-section should not get one.

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[1] http://jamanetwork.com/journals/jama/fullarticle/2473490

[2] http://www.who.int/healthsystems/topics/financing/healthreport/30C-sectioncosts.pdf

Every 1 in 3 babies in US is delivered by C-section.

Cesarean section is the number one surgery performed in US today, even surpassing all the orthopedic and heart surgeries. About 1.3 million babies are delivered by Cesarean every year, which roughly equals to every 1 in every 3 children born in US.  This is in stark contrast to a world cesarean section rate of 19%, according to data published in the Journal of the American Medical Association in December, 2015. 

United states have seen a steep rise in the C-section rate from 5 percent in 1970 to nearly 33% in 2016.

Consumer report finds a wide variation across US and also among different hospitals in the same region. The rate for low risk deliveries varies from 11% to 53% state wise to 17% to 30% in the same community. In fact Hialeah Hospital, outside of Miami, had the highest C-section rate of 66% of all hospitals in US. In fact, there were 221 hospitals in the U.S. with C-section rates above 33.3 percent for low-risk deliveries.

The National Target is 23.9% for nulliparous, low risk women, with only 40% of the hospitals meeting the target. Researchers estimate that almost half of all the C-sections could be avoided and babies delivered safely by vaginal route.

The American Congress of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM) were so concerned by the rising rate that they jointly issued a recommendations  to prevent the first C-section.

Dr. Thomas Weiser, an assistant professor of surgery at Stanford School of Medicine says “As countries increase the number of C-sections they provide, mortality goes down— but only to a point, when the C-section rate tops 19 percent, benefits for maternal and infant health plateau.”

Aaron B. Caughey, M.D., chair of the Department of Obstetrics and Gynecology at Oregon Health & Science University School of Medicine in Portland and a lead author of the new ACOG/SMFM recommendations says “Once cesarean rates get well above the 20s and into the 30s, there are probably a lot of non-medically indicated cesareans being done, that’s not good medicine.”

But, the rise in Cesarean rates have not helped in bringing down the mortality and infant mortality rates in US, which sadly stands at 14 deaths per 100,000 live births and 5.6 per  1000 babies respectively, far worse than other developed countries, according to CDC statistics.

So, what are the causes for such high C section rates in  US? 

• Repeat cesarean section was the most common indication with low rate of VBAC constituting about one third of all cesarean deliveries.
• Experts blame a part of it on technology advances like continuous fetal monitoring.  Continuous FHR monitoring is not backed by extensive research when it comes to interpreting the results. Different obstetricians have different policies and when they see ups and down in the FHR tracing, it may trigger a Cesarean Section, even if it is not clear whether the baby is actually in distress.
•  In approximately 44% of patients, the labor was induced instead of allowing them to go into spontaneous labor. These patients had C-section rate twice that of patients who opted for a natural onset of labor.
• Obstetricians in USA are sued a lot, so the idea of practicing ‘defensive medicine’ prevails in the labor room also. It is always justified to explain a mishap in labor when cesarean section was performed than being delivered vaginally.
• Women is US can choose to be delivered by cesarean section like most western countries.  According to a study Zhang et al in American Journal of Obstetrics and Gynecology elective cesarean section accounts for less than 10% of all scheduled procedures.
• And the current focus in obstetrics is to manage postpartum hemorrhage, prevention of thromboembolism and ecclampsia which have all shown an increasing trend.

So, to bring down the cesarean section rate in US, preventing unnecessary primary cesarean deliveries is the key, because they contribute to one third of total cesarean deliveries.

If first Cesarean is prevented than we are preventing the subsequent ones down the lane. According to Dr. Shah from Harvard Medical school Right now in the U.S., if you get a C-section the first time, you have a 90 percent chance of getting another one the second time. 

If the fetus status is reassuring than awaiting for vaginal births in patients with dystocia could also bring down the rate. A further small reduction can be achieved by external cephalic version (2-3%) and attempting VBAC.

References:

http://www.cdc.gov/reproductivehealth/maternalinfanthealth/infantmortality.htm

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2947574/

http://www.consumerreports.org/doctors-hospitals/your-biggest-c-section-risk-may-be-your-hospital/

http://www.acog.org/Resources-And-Publications/Obstetric-Care-Consensus-Series/Safe-Prevention-of-the-Primary-Cesarean-Delivery

https://www.statnews.com/2015/12/01/cesarean-section-childbirth/