Tag: caesarean

Categories : Pain Management Surgeries & ProceduresTags :

A Handful of Procedures Account for Large Share of Post-surgical Opioids

On By ModernMedia
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A handful of common surgical procedures account for large shares of all opioids dispensed after surgery in children and adults, according to two studies recently published by researchers at the University of Michigan.

The studies, published this week in Pediatrics and JAMA Network Open, report that the top three procedures for children ages 0–11 account for 59% of opioids dispensed after surgery (tonsillectomies and adenoidectomies 50%, upper extremity fractures 5% and removal of deep implants 4%). Among those ages 12–21, the top three procedures account for about a third of post-surgery opioid prescriptions (tonsillectomies and adenoidectomies 13%, knee arthroscopies 13% and caesarean deliveries 8%).

For adults ages 18–44, C-sections account for the highest share of opioids dispensed post-surgery (19%), followed by hysterectomies (7%) and knee arthroscopies (6%). Among those ages 45-64, four of the top five procedures were orthopaedic procedures, collectively accounting for 27% of total opioid prescriptions dispensed after surgery.

“Our findings suggest that surgical opioid prescribing is highly concentrated among a small group of procedures. Efforts to ensure safe and appropriate surgical opioid prescribing should focus on these procedures,” said Kao-Ping Chua, lead author of the study in Pediatrics, assistant professor at the U-M Medical School and School of Public Health, and co-director of the Research and Data Domain at the U-M Opioid Research Institute.

To conduct the study, the researchers developed an algorithm to identify 1082 major surgical procedures using procedure codes, a medical classification tool used to identify specific surgical, medical or diagnostic interventions. The algorithm was then applied to identify privately and publicly insured children and adults undergoing surgery from Dec. 1, 2020 through Nov. 30, 2021.

The information was organized through a novel system developed by the study team, which allowed them to connect different sets of data that had previously been seen as unrelated. This new method allows for improved comparability and contrast, according to lead investigators.

In addition to determining which procedures accounted for the highest shares of opioids, the researchers also examined the size of opioid prescriptions for each procedure. For many procedures, prescriptions were far larger than the amount patients typically need for a particular procedure.

“Our findings suggest that there are important opportunities to reduce surgical opioid prescribing without compromising pain control,” said Dominic Alessio-Bilowus, lead author of the paper focused on adults published in JAMA Network Open and a medical student at Wayne State University who just completed a research year at U-M.

Source: University of Michigan

Categories : Obstetrics & Gynaecology VaccinesTags :

Birth by C-section More than Doubles Odds of Measles Vaccine Failure

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A study by the University of Cambridge, UK, and Fudan University, China, has found that a single dose of the measles jab is up to 2.6 times more likely to be completely ineffective in children born by C-section, compared to those born naturally.

Failure of the vaccine means that the child’s immune system does not produce antibodies to fight against measles infection, so they remain susceptible to the disease.

A second measles jab was found to induce a robust immunity against measles in C-section children.

Measles is a highly infectious disease, and even low vaccine failure rates can significantly increase the risk of an outbreak.

A potential reason for this effect is linked to the development of the infant’s gut microbiome — the vast collection of microbes that naturally live inside the gut. Other studies have shown that vaginal birth transfers a greater variety of microbes from mother to baby, which can boost the immune system.

“We’ve discovered that the way we’re born – either by C-section or natural birth – has long-term consequences on our immunity to diseases as we grow up,” said Professor Henrik Salje in the University of Cambridge?’s Department of Genetics, joint senior author of the report.

He added: “We know that a lot of children don’t end up having their second measles jab, which is dangerous for them as individuals and for the wider population.

“Infants born by C-section are the ones we really want to be following up to make sure they get their second measles jab, because their first jab is much more likely to fail.”

The results are published today in the journal Nature Microbiology.

At least 95% of the population needs to be fully vaccinated to keep measles under control but the UK is well below this, despite the Measles, Mumps and Rubella (MMR) vaccine being available through the NHS Routine Childhood Immunisation Programme.

An increasing number of women around the world are choosing to give birth by caesarean section: in the UK a third of all births are by C-section, in Brazil and Turkey over half of all children are born this way.

“With a C-section birth, children aren’t exposed to the mother’s microbiome in the same way as with a vaginal birth. We think this means they take longer to catch up in developing their gut microbiome, and with it, the ability of the immune system to be primed by vaccines against diseases including measles,” said Salje.

To get their results, the researchers used data from previous studies of over 1500 children in Hunan, China, which included blood samples taken every few weeks from birth to the age of 12. This allowed them to see how levels of measles antibodies in the blood change over the first few years of life, including following vaccination.

They found that 12% of children born via caesarean section had no immune response to their first measles vaccination, as compared to 5% of children born by vaginal delivery. This means that many of the children born by C-section did still mount an immune response following their first vaccination.

Two doses of the measles jab are needed for the body to mount a long-lasting immune response and protect against measles. According to the World Health Organization, in 2022 only 83% of the world’s children had received one dose of measles vaccine by their first birthday – the lowest since 2008.

Salje said: “Vaccine hesitancy is really problematic, and measles is top of the list of diseases we’re worried about because it’s so infectious.”

Measles is one of the world’s most contagious diseases, spread by coughs and sneezes. It starts with cold-like symptoms and a rash, and can lead to serious complications including blindness, seizures, and death.

Before the measles vaccine was introduced in 1963, there were major measles epidemics every few years causing an estimated 2.6 million deaths each year.

The research was funded by the National Natural Science Foundation of China.

The original text of this story is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International Licence.

Source: University of Cambridge

Categories : Obstetrics & GynaecologyTags :

New Intrauterine Device Rapidly Controls Postpartum Haemorrhage

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A study led by Columbia University obstetricians has shown that a new intrauterine device can rapidly control postpartum haemorrhage, a major cause of severe maternal morbidity and death, in real-world situations.

“Our findings show that the device is an important new tool in managing postpartum bleeding,” says Dena Goffman, MD, professor of obstetrics and gynaecology at Columbia University and senior author of the study, which is published in the journal Obstetrics & Gynecology.

“We had previously shown that the device worked well with patients who were experiencing relatively minor bleeding, so it’s really reassuring to see that the device worked almost as well among a wider range of patients and when used by many different doctors.”

Overall, the device succeeded in controlling haemorrhage in 93% of vaginal deliveries and 84% of caesarean deliveries.

Major cause of severe maternal morbidity and death

Shortly after birth and delivery of the placenta, the uterus contracts and closes off the blood vessels that nourished the placenta. Failure of the uterus to contract after delivery can result in prolonged and excessive blood loss, which may necessitate blood transfusions, ICU admission, or surgery to try to stop the bleeding and, if needed, removal of the uterus.

“Less than 10% of people who give birth will have excessive postpartum bleeding, but when it happens, it can get really serious really fast,” says Goffman, who co-authored the most recent guidelines from the American College of Obstetrics and Gynecology for the treatment of postpartum haemorrhage.

Current treatment options not ideal for all patients

To stop excessive bleeding, clinicians usually start by manually stimulating the uterus and giving medications that help the uterus contract, but some of these drugs are not safe for patients with hypertension or asthma. When medication fails or isn’t an option, patients may be treated with a balloon-like tamponade device that is inserted into the uterus and controls bleeding by placing pressure on the uterine wall.

Balloon tamponade devices have a high success rate, but this treatment has an impact on the patient and family experience. “The balloon often stays in the uterus for 12 to 24 hours until the uterus is well-contracted, and during that time the patient can’t sit up in bed, can’t walk around, can’t easily care for the baby,” Goffman says.

New device approved in 2020

In 2020, the FDA approved a new intrauterine device to control postpartum bleeding that uses low-level suction to promote uterine contractions.

“With postpartum haemorrhage being one of the most preventable causes of maternal morbidity and mortality, practice-changing innovation was needed to better equip our teams and care for our patients,” says Mary D’Alton, MD, chair of the Department of Obstetrics & Gynecology at Columbia University Vagelos College of Physicians and Surgeons and national leader of the clinical trial that first tested the safety and efficacy of the device.

In that initial trial, which led to FDA approval, the device controlled bleeding in a median of 3 minutes among 106 patients experiencing relatively minor blood loss after childbirth and was removed about 3 hours after insertion. Most patients in the trial delivered vaginally. The trial also excluded patients with preterm births < 34 weeks.

Highly effective in real-world conditions

The current study, which included more than 800 patients giving birth at 16 hospitals, was designed to study the effectiveness of the new device outside of a controlled clinical trial. One third of the patients in the new study had a caesarean, and 50 patients had a preterm birth < 34 weeks.

Median blood loss volume before device insertion was also higher in the new study, reflecting a greater range in blood loss, with some patients losing substantial amounts of blood (up to 3000mL). Most patients had been treated with medications to manage postpartum bleeding prior to device insertion.

Treatment with the new device was successful in 93% of patients who had a vaginal birth and 84% of patients who had a caesarean birth (similar to efficacy with intrauterine balloon devices). For most patients, the device brought bleeding under control in five minutes. Treatment success rates were higher in patients with less blood loss prior to device insertion.

Next steps

The researchers say that early recognition of postpartum hemorrhage and timely intervention are crucial in managing the condition and preventing potentially life-threatening complications.

“Postpartum haemorrhage is a treatable condition,” Goffman says. “Delivery teams need to be attuned to recognising it quickly and managing it in a seamless and sequential manner before a patient experiences significant blood loss.”

Additional studies comparing the new device with other treatments for postpartum haemorrhage are being planned to determine if using the device earlier produces better outcomes.

“Until we have more data, we’re using the new intrauterine device after medications have been tried,” Goffman says. “But for patients with underlying conditions who cannot be treated with one or more of our available medications, the device is a critically important tool to have.”

Source: Columbia University Irving Medical Center

Categories : Obstetrics & GynaecologyTags :

Labour Induction in 39th Week Does not Decrease Risk of Needing Caesarean

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In recent years, experts have debated the benefits of labour induction once at a certain stage of pregnancy. But a new US study suggests that inducing labour at the 39th week of pregnancy for those having their first births with a single baby in a head down position, or low risk, doesn’t necessarily reduce the risk of caesarean births. In fact, for some, it may even have the opposite effect if hospitals don’t take a thoughtful approach to induction policies.

“Some people in the field have suggested that after 39 weeks of gestation, medical induction should be standard practice,” said lead author Elizabeth Langen, MD, a high-risk maternal fatal medicine physician and researcher at University of Michigan Health Von Voigtlander Women’s Hospital, of Michigan Medicine.

“We collaborated with peer hospitals to better understand how labour induction may influence caesarean birth outcomes in real world maternity units outside of a clinical trial. In our study sample, we found inducing labour in this population of women and birthing people did not reduce their risk of caesarean birth.”

The new research, published in the American Journal of Perinatology, was based on more than 14 135 deliveries in 2020 analysed through a statewide maternity care quality collaborative registry.

Results conflict with national trial findings

The study was conducted in response to published research in 2018 from a multicentre trial known as “ARRIVE” (A Randomized Trial of Induction Versus Expectant Management.)

Findings from ARRIVE indicated that medical induction at 39 weeks gestation in first time low risk pregnancies resulted in a lower rate of caesarean deliveries compared to expectant management – or waiting for labour to occur on its own or for a medical need for labour induction.

Michigan researchers mimicked the same framework used in the national trial and analysed data from the collaborative’s data registry, comparing 1558 patients who underwent a proactively induced labour versus 12 577 who experienced expectant management. However, their results failed to support a link between elective induced labour in late pregnancy and a reduction in caesarean births.

In fact, results from the general Michigan sample were contradictory to the ARRIVE trial: Women who underwent elective induction were more likely to have a caesarean birth compared with those who underwent expectant management (30% versus 24%.)

In a subset of the sample, matching patient characteristics for a more refined analysis, there were no differences in c-section rates. Authors noted that time between admission and delivery was also longer for those induced.

Expectantly managed women were also less likely to have a postpartum haemorrhage (8 % versus 10 %) or operative vaginal delivery (9 % versus 11 %), whereas women who underwent induction were less likely to have a hypertensive disorder of pregnancy (6 % versus 9%.) There were no other differences in neonatal outcomes.

Authors point to several possible explanations for why the two studies had conflicting results. One key difference was that the Michigan study collected data after births for the purpose of quality improvement in a general population of low-risk births. The ARRIVE trial, however, used data collected in real time as part of a research study.

A significant difference between clinical trial participants and the general birthing population, Low says, may revolve around shared decision-making. Before trial enrolment, participants undergo a thorough informed consent process from trained study team members.

For the ARRIVE trial, this meant 72% of women approached to be in the study declined participation. Meanwhile, previous research has indicated that women in the general U.S. population often may feel pressured into agreeing to have their labour induced.

“Better outcomes may have occurred in the trial because the participants were fully accepting of this process,” Low said.

“Further research is needed to identify best practices to support people undergoing labour induction,” she added. “Prior to initiating an elective induction of labour policy, clinicians should also ensure resources and a process to fully support shared decision-making.”

Source: Michigan Medicine – University of Michigan

Categories : Cardiovascular Disease Obstetrics & GynaecologyTags :

C-section Delivery Linked to Later CVD Risk

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A new Australian and New Zealand Journal of Public Health study has found that Australian children who were born via caesarean section (C-section) have a greater risk of cardiovascular disease (CVD) and obesity. These findings have prompted a call to limit the increasingly popular practice.

According to a Lancet review, C-sections are already known to have a number of negative outcomes, with evidence higher rates of maternal mortality and morbidity than after vaginal birth. C-sections are further associated with an increased risk of uterine rupture, abnormal placentation, ectopic pregnancy, stillbirth, and preterm birth. Short-term risks of C-section include altered immune development, an increased likelihood of allergy, atopy, and asthma, and reduced gut microbiome diversity. Associations of C-section with greater incidence of late childhood obesity and asthma are frequently reported.

Researchers used data from the Longitudinal Study of Australian Children to analyse the health outcomes of children delivered by C-section.

“C-section births have risen across the world with a disproportionately higher rate in developed countries. In Australia, the C-section birth rate has increased from 18.5% in 1990 to 36% in 2019 and nearly half of Australian babies are projected to be caesarean born by 2045,” said study author Dr Tahmina Begum.

A relationship was discovered between C-section births and certain cardiovascular disease (CVD) risk factors in children.

“Four out of six individual CVD risk components and the composite index of the five CVD risk components showed a positive association with C-section birth. Our study also provided a direct relationship between C-section and increased overweight and obesity among children at 10–12 years of age,” said Dr Fatima.

A biologically plausible link involved the gut microbiome, she said. “There’s an altered microbial load from C-section birth as compared to vaginal birth. This altered microbial ecosystem hampers the ‘gut-brain axis’ and releases some pathogenic toxins that cause metabolic damage.”

Other possible causes included foetal stress from physiological or pharmacological induction of labour during a C-section. She said the study provides important insights into health care policy and the strategic direction towards chronic disease risk reduction.

“Growing rates of C-sections conducted for non-clinical reasons is a major public health concern that calls for a reduction in the rate of unnecessary C-sections and their associated human and economic costs,” said Dr Begum.

Source: James Cook University

Categories : Allergies Obstetrics & GynaecologyTags :

No Food Allergy Link to Caesarean Delivery

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Man holding newborn baby
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A new study found that caesarean delivery, either with or without labour, or elective or emergency, compared to vaginal birth does not impact on the likelihood of food allergy at 12 months of age. Led by the Murdoch Children’s Research Institute (MCRI), the study was published in the Journal of Allergy and Clinical Immunology: In Practice.

Associate Professor Rachel Peters of the Children’s Research Institute (MCRI) said the association between food allergy and mode of delivery remained unclear due to the lack of studies with food challenge outcomes.

The study involved 2045 infants from the HealthNuts study, with data linked to a perinatal database for detailed information on birth factors.

The study found that, of the 30% born by caesarean, 12.7% had a food allergy compared to 13.2% born vaginally.

“We found no meaningful differences in food allergy for infants born by caesarean delivery compared to those born by vaginal delivery,” Associate Professor Peters said. “Additionally, there was no difference in the likelihood of food allergy if the caesarean was performed before or after the onset of labour, or whether it was an emergency or elective caesarean.”

Associate Professor Peters said it was thought a potential link between caesarean birth and allergy could reflect differences in early microbial exposure from the mother’s vagina during delivery.

“The infant immune system undergoes rapid development during the neonatal period,” she said. Caesarean delivery may interfere with the normal development of the immune system, as there is less exposure to the mother’s vagina and gut bacteria, influencing the baby’s own microbiome. “However, this doesn’t appear to play a major role in the development of food allergy.”

Australia has the highest rates of childhood food allergy in the world, with about one in 10 infants and one in 20 children over five years of age having a food allergy.

These findings come as other MCRI-led research found 30% of peanut allergy and 90% of egg allergy resolves naturally by age six.

Associate Professor Peters said the resolution rates were great news for families and were even a little higher than what was previously thought.

The results, published in the Journal of Allergy and Clinical Immunology, found infants with early-onset and severe eczema and multiple allergies were less likely to outgrow their egg and peanut allergies.

Associate Professor Peters said these infants should be targeted for early intervention trials that evaluate new treatments for food allergy such as oral immunotherapy.

“Prioritising research of these and future interventions for infants less likely to naturally outgrow their allergy would yield the most benefit for healthcare resources and research funding,” she said.

Source: SciTech Daily

Categories : COVID Obstetrics & GynaecologyTags :

Caesarean and Induced Deliveries Fell During Pandemic

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During the first few months of the COVID pandemic, premature births from caesarean and induced deliveries fell by 6.5% – and remained consistently lower throughout, according to research reported in the journal Pediatrics. This is likely a result of fewer prenatal visits due to lockdown and social distancing rules, the researchers suggested, and call into question how many such interventions are necessary.   

The study, the first to examine pandemic-era birth data at scale, raises questions about medical interventions in pregnancy and whether some decisions by doctors may result in unnecessary preterm deliveries, according to Assistant Professor Daniel Dench, the paper’s lead author.

“While much more research needs to be done, including understanding how these changes affected fetal deaths and how doctors triaged patient care by risk category during the pandemic, these are significant findings that should spark discussion in the medical community,” A/Prof Dench said.

In effect, the study begins to answer a question that never could have been resolved in a traditional experiment: What would happen to the rate of premature C-sections and induced deliveries if women didn’t see doctors as often, especially in person, during pregnancy?

Doing such a study would be unethical, but lockdown had a side effect of reducing prenatal care visits by more than a third, according to one analysis. That gave A/Prof Dench and colleagues an opportunity to evaluate the impacts, after all.

The researchers took records of nearly 39 million US births from 2010 to 2020, and compared them to expected premature births (born before 37 weeks) from March to December 2020. 

The researchers found that in March 2020, when lockdowns began in the US, preterm births from C-sections or induced deliveries immediately fell from the forecasted number by 0.4%. From March 2020 to December 2020, the number remained on average 0.35% below the predicted values. That translates to 350 fewer preterm C-sections and induced deliveries per 100 000 live births, or 10 000 fewer overall.

Before the pandemic, the number of preterm C-sections and induced deliveries had been rising. Spontaneous preterm births also fell by a small percentage in the first months of the pandemic, but much less than births involving those two factors. The number of full-term caesarean and induced deliveries increased.

“If you look at 1000 births in a single hospital, or even at 30 000 births across a hospital system, you wouldn’t be able to see the drop as clearly,” said A/Prof Dench. “The drop we detected is a huge change, but you might miss it in a small sample.”  

The researchers also corrected for seasonality, for example, preterm births are higher on average in February than in March, which helped them get a clearer picture of the data.

The research comes with caveats. Up to half of all preterm C-sections and induced deliveries are due to a ruptured membrane, which is a spontaneous cause. But in the data Dench and his team used, it’s impossible to distinguish these C-sections from the ones caused by doctors’ interventions. So, Dench and co-authors are seeking more detailed data to get a clearer picture of preterm deliveries.

Still, these findings are significant because the causes for preterm births are not always known.

“However, we know for certain that doctors’ interventions cause preterm delivery, and for good reason most of the time,” A/Prof Dench said. “So, when I saw the change in preterm births, I thought, if anything changed preterm delivery, it probably had to be some change in how doctors were treating patients.”

The researchers’ findings raise a critical question: Was the pre-pandemic level of doctor intervention necessary?

“It’s really about, how does this affect foetal health?” said A/Prof Dench. “Did doctors miss some false positives – did they just not deliver the babies that would have survived anyway? Or did they miss some babies that would die in the womb without intervention?”  

A/Prof Dench plans to use foetal death records from March 2020 to December 2020 to answer this question. If he finds no change in foetal deaths at the same time as the drop in preterm births, that could point to “false positives” in doctor intervention that can be avoided in the future. Learning which pregnancies required care during the pandemic and which ones didn’t could help doctors avoid unnecessary interventions in the future.  

“This is just the start of what I think will be an important line of research,” A/Prof Dench said.

Source: Georgia Institute of Technology

Categories : Obstetrics & GynaecologyTags :

WHO Warns of Lethal Tranexamic Acid Mix-ups in Intrathecal Administration

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Intravenous IV drip in woman's hand
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The World Health Organization is alerting health care professionals about the risk of lethal administration errors that can potentially occur with tranexamic acid (TXA) injection. There have been reports of TXA being mistaken for obstetric spinal anaesthesia used for caesarean deliveries resulting in inadvertent intrathecal administration.

Intrathecal TXA is a potent neurotoxin and neurological sequelae are manifested, with refractory seizures and 50% mortality. The profound toxicity of intrathecal TXA was described in 1980. In a 2019 review, Patel et al. identified 21 reported cases of inadvertent intrathecal injection of TXA since 1988, of which 20 were life-threatening and 10 fatal. It appears that mortality risk is greater after caesarean delivery. Sixteen were reported between 2009 and 2018.

WHO recommends early use of intravenous TXA within three hours of birth in addition to standard care for women with clinically diagnosed postpartum haemorrhage (PPH) following vaginal births or caesarean section. TXA should be administered at a fixed dose of 1g in 10 ml (100 mg/ml) IV at 1 ml per minute, with a second dose of 1g IV if bleeding continues after 30 minutes. In South Africa, the incidence of maternal bleeding after caesarean delivery has been characterised as a national emergency, and obstetric haemorrhage remains the third most common cause of maternal mortality at 17%.

However, problems can arise as TXA is frequently stored in close proximity with other medicines, including injectable local anaesthetics indicated for spinal analgesia (eg, for caesarean section). The presentation of some of the local anaesthetics is similar to the TXA presentation (transparent ampoule containing transparent solution), which can be administered in error instead of the intended intrathecal anaesthetic, and resulting in serious undesirable adverse effects.

Obstetricians from several countries have recently reported inadvertent intrathecal TXA administration and related serious neurological injuries. In a South African clinical alert, Bishop et al. highlighted the different appearances of TXA used in state and private hospitals, with one example in private hospitals appearing very similar (white label, red text) at first glance to spinal bupivacaine and stored in the same container. Applicable recommendations were provided by the authors.

TXA is a lifesaving medicine, however, this potential clinical risk should be considered and addressed by all operating theatre staff. Reviewing of existing operating theatre drug handling practice is required in order to decrease this risk, such as storage of TXA away from the anaesthetic drug trolley, preferably outside the theatre.

Source: World Health Organization

Categories : COVID Obstetrics & GynaecologyTags :

Severe COVID Raises Risk of Pregnancy Complications

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Source: Pixabay

A University of Oxford study of over 4000 pregnant women indicates that severe COVID in pregnancy increases the risk of pre-labour caesarean birth, a very or extreme preterm birth, stillborn birth, and the need for admission to a neonatal unit.  

The study, published in Acta Obstetricia et Gynecologica Scandinavica, included 4436 pregnant women hospitalised in the UK with symptomatic COVID from March 1, 2020 to October 31, 2021, of whom 13.9% of had severe COVID. As well as having increased risks of adverse pregnancy-related outcomes, women with severe infection were more likely to be aged 30 years or over, be overweight or obese, be of mixed ethnicity, or have gestational diabetes compared with those with mild or moderate infection.  

“This new analysis shows that certain pregnant women admitted to a hospital with COVID face an elevated risk of severe disease. However, it shows once again the strongly protective effect of vaccination against severe disease and adverse outcomes for both mother and baby,” said senior author Marian Knight, FMedSci, of the University of Oxford. “This study emphasises the importance of ensuring that interventions to promote vaccine uptake are particularly focused towards those at highest risk.”

Source: Wiley