The initiation of a neuraxial analgesia service on the rate of cesarean delivery in Hubei, China. a 1-year restrospective studyThe initiation of a neuraxial analgesia service on the rate of cesarean delivery in Hubei, China. a 1-year restrospective study

Background No Pain Labor Delivery (NPLD) is a nongovernmental project to increase access to safe neuraxial analgesia through specialized training. This study explores the change is overall cesarean delivery (CD) and maternal request CD(MRCD) rate in our hospital after the initiation of neuraxial analgesia service. Methods The neuraxial labor analgesiaNA was initiated in May 1st 2015 by the help of NPLD. Since then, the application of NA became a routine operation in our hospital, and every parturient can choose to use NA or not according to her own requirement. The monthly rates of NA, CD, MRCD, multiparous women, intrapartum CD, episiotomy, postpartum hemorrhage (PPH), operative vaginal delivery and neonatal asphyxia of vaginal delivery were analyzed from May 1st 2015 to April 30th 2016. Results The rate of NA in our hospital was getting increasingly higher from 26.1% in May 2015 to 44.6% in April 2016 (p<0.001); the rate of CD was decreased from 50.4% in May 2015 to 36.3% in April 2016 ( p<0.001); the rate of MRCD was decreased from 10.8% in May 2015 to 5.7% in April 2016 (p<0.001), but the rate of multiparous women had no change (p0.05). There was a negative correlation between the rate of NA and that of overall CD, r=-0.803 (95%CI[-0.951, -0.642], p=0.002), and also a negative correlation between the utilization rate of NA and that of MRCD, r=-0.790 (95%CI[-0.971, -0.497], p=0.004). The rates of episiotomy, PPH, operative vaginal delivery and neonatal asphyxia in women underwent vaginal delivery as well as the rates of intrapartum CD, neonatal asphyxia, and PPH in women underwent CD remained unchanged from May 1st 2015 to April 30th 2016. Conclusions: Our study shows that the rates of CD and MRCD in our department significantly were decreased over a year period (2015. 05.01~2016. 04.30), which may be due to the increasing use of NA during vaginal delivery by the help of NPLD.


Background
The rate of cesarean delivery (CD) in China [1][2][3][4][5] has risen markedly from 2.0% (14/701) in 1978-1985 to 36.6% (813/2224) during 2006-2010 [1] . In the recent years, nearly half of all newborns in China were delivered by CD [2,3] , among which 23.2% were performed based on maternal request cesarean delivery (MRCD) rather than on medical indications [6] . The high rate of overall CD may result in increased risk of maternal complications such as infection, hemorrhage, or even death [6] . Previous researches have showed that Chinese women choose CD only to avoid the pain during vaginal delivery, because normally no analgesia will be given during their labor and delivery in China [2,7] .
Neuraxial labor analgesia (NA) is a safe and commonly available method in developed countries [7] , which has been recommended as a proactive approach for high-risk parturient during labor [8] . However, very few hospitals in China regularly carry out this approach at present [3,4] . A high CD rate and low or no availability of NA for labor is a common situation in Chinese hospitals. No Pain Labor Delivery(NPLD) is a nongovernment project, which was proposed by an anesthesiologist named Ling-Qun Hu at the Northwestern University Feinberg School of Medicine, and launched in 2008. After 10 years of efforts, this project has been supported by many nongovernment organizations from both America and China [7] . Before the use of NA, common services provided in our delivery room include midwives service, accompanying family members, and water immersion service [9] during the first stage of labor if patients had requirement(about 20% of them chose water immersion delivery). With the help of NPLD, NA has been regularly carried out in our hospital since May 1st, 2015.
This study is an retrospective study to evaluate the correlation between NA availability 4 and the rate of overall CD, MRCD, episiotomy, postpartum hemorrhage (PPH), operative vaginal delivery and neonatal asphyxia in women undergoing vaginal delivery, and intrapartum CD and neonatal asphyxia in women undergoing cesarean delivery after regular implementation of NA in our hospital from May 1st, 2015 to April 30th, 2016.

Participants and methods
This study was conducted from May 1st, 2015 to April 30th, 2016 in our hospital, a tertiary-care teaching hospital in Hubei province, in the central of China.

Ethical approval
The study protocol was approved by the Ethics Committee of Maternal and Child Health Hospital of Hubei Province (Record No. 2015008) on September 23th, 2017. All parturient women requiring the NA service had signed informed consent.

Preparation stage of NA in our hospital
On March 1st, 2015, an organizing committee of NA was founded, which consisted of 10 members from our hospital, including administrators, anesthesiologists, obstetricians, neonatologist, nurses, midwives, and 3 experts from NPLD team. Of the members in the founded committee, three experts were born and educated in China and then immigrated to the United States for further academic development. They were fluent in both Mandarin and English and familiar with Western standards of obstetric care. In our hospital, a meeting is regularly organized 1-2 times a week. Questions would be discussed and communicated with the experts from NPLD through WeChat (the most popular online chat platform in China designed by Tencent Company), and the care givers of operator from our hospital were versed in the institution of epidural and had more than 5 years of work experience in the department of anesthesia(attending physician) and took turns to observe at least 7 days in the hospitals that had helped by NPLD in China.
Before May 1st, 2015, cesarean section could not be carried out in labor and delivery suite. The process can be described as that all pregnant women with labor onset were generally transferred to labor and delivery suite when the dilation of cervix was more than 1 cm. If intrapartum CD was needed in labor, they would be transferred to the operating suite. In our labor and delivery suite, various . However, during labor, no NA could be provided, nearly 20% of them chose water immersion during first stage of labor. All of the parturient women received bilateral perineal block anesthesia when the fetal head was crowned. After delivery, all of postpartum women would be returned to maternity room again.
After May 1st, 2015, with the help of NPLD team via WeChat, NA could be provided every day at any time in our labor and delivery suite. One of our labor and delivery suites (total 10 rooms) was also set as operation suite for intrapartum CD, in which there would be an anesthesiologist and an anesthesia nurse on duty every day, two shifts a day, at 8:00am and 17:00 pm, respectively.

The NPLD program in our hospital
From June 21 to 27 of 2015, a professional NPLD team from American travelled to our hospital to give us a one-week training. This American team [7] consisted of 4 obstetric anesthesiology attending physicians, 2 anesthesiology residents, 1 obstetrician, 1 labor and delivery nurse, 1 neonatologist, and 3 interpreters (Supplementary file 1). The were held at the end of each day. The practiced drills included 5-minute crash CD, how to deal with neurological complications in labor and delivery suite, how to use operation instrument during vaginal delivery, how to reduce the rate of episiotomy, and how to perform resuscitation of neonatal asphyxia.

Data sources
This retrospective study focused on the maternity departments of a tertiary-level public hospital in Wuhan, China. This is a big birth center, where the annual number of newborn babies were around 20.000 in recent 3 years. The delivery data were collected from the hospital's information system from May 1st, 2015 to April 30 th, 2016. A total of 20 174 deliveries were included in our study, of which 40 cases of incomplete information, 20 cases of abortion before 28 weeks' gestation, 601 cases of labor induction for fetal malformation, 49 cases of intrauterine fetal death were excluded. Therefore, a complete data of 19 464 cases was finally included (accounting for of all the data 96.48%). The data set contains information such as demographic data, mother's age, gravidity, parity, date of delivery, principal diagnosis of maternal or fetal pregnancy-related complications, gestational age at delivery, mode of delivery, primary indications of CD, maternal request cesarean delivery(MRCD), intrapartum CD, whether or not using NA, episiotomy, postpartum hemorrhage (PPH), operation vaginal delivery, neonatal asphyxia. (See Fig 1) In China, CD with medical indications can be divided into CD with absolute medical indications and CD with relative medical indications (for instance age more than 35 years). In our study, MRCD refers to a cesarean delivery on maternal request, which lacks any medical indications of absolute and relative medical indication according to the classification standards above [10,11] .

Neuraxial labor analgesia
Women undergoing vaginal delivery were evaluated both by anesthesiologist and 7 obstetrician to assess their desire for and suitability for NA once their cervical dilation was greater than 1 cm. Parturient women who had any systemic and local sepsis, had deranged coagulation profile, or had drug allergy (Lidocaine, bupivacaine and fentanyl) were excluded from the study. The detail records for NA can be listed according to nulliparous or parous, spontaneous labor or medicine induced labor, full-term delivery or premature delivery, spontaneous vaginal delivery or instrument assisted vaginal delivery or intrapartum CD. Except for Epidural analgesia was initiated in the left lateral decubitus position. A sterile preparation with 1% alcohol iodophor was applied by an anesthesiologist after at least 500 mL of Ringer's lactate solution was administered by an anesthesia nurse. Then, an 18-gauge epidural catheter was inserted into the epidural space at the L3-4 or L4-5 interspace.
After giving 2-3 mL test dose of 2% lidocaine, if there was no adverse reaction after 5 min, the catheter was fixed and connected to a patient controlled epidural analgesia (PCEA) pump (Master PCA pump, Fresenius Kabi USA, without continuous background infusion) to give 10 mL of mixed drugs of 0.08% ropivacaine +2ug/mL fentanyl. The PCEA pump was set to an automatic mode to deliver a 10 mL dose with a lockout time of 1 hour. We advised the patient to push the PCEA button whenever she felt uncomfortable. If the pain relief was inadequate, 15 minutes after having activated the PCEA bolus, a bolus dose of 10 mL was manually given. The continuous infusion rate was set to 0mL/h. Anesthesia infusion was stopped after finishing the perineal stitch and was removed in two hours after delivery generally.
Maternal HR, NIBP and SpO2 were continuously monitored throughout the PCEA period, meanwhile the fetal heart rate was monitored continuously as well. Parturient women were supervised by midwife one-on-one, and observed by anesthesia nurse at regular intervals. Common side effects such as nausea, somnolence, and pruritus were recorded 8 by anesthesia nurses. The PCEA pump was administered by the parturient woman herself according to the instruction of anesthesiologist. Parturient women received exogenous oxytocin to obtain an enhanced labor process when they need. All fetal and maternal events, therapeutic interventions, outcome of labor, and Apgar score of new born at 1 and 5 min, PPH, and the mode of delivery were recorded. The analgesia effect was evaluated by visual analog scale (VAS) and numerical rating scale (NRS). The VAS was assessed on a 10 cm horizontal line. The patients were informed that the left end of the scale represented "no pain" and that the right end represented the "most severe pain imaginable". The patients were then instructed to mark the intensity of pain they were currently experiencing on the line. For the NRS an 11-point scale was used, with "0" representing "no pain" and "10" representing the "most severe pain imaginable." All pain assessments were performed by the anesthesiologist before and after NA. After delivery, there was a questionnaire survey about labor including the satisfaction degree on the NA effect by scanning the code on WeChat.

Patient's education
All our patients were educated by obstetrician in prenatal examination and the brochure for NA were given to them. On working day, midwives conducted specialized classes about NA for pregnant women to teach them how to improve compliance during analgesia.
Women undergoing vaginal delivery were evaluated both by anesthesiologist and obstetrician to assess their desire for and suitability for NA once their cervical dilation was greater than 1 cm and all of them signed written informed consent for NA. Women undergoing vaginal delivery also could choose water immersion delivery once their cervical dilation was greater than 5 cm.

Data analysis
All data were inputted into SPSS software (v.19.0, SPSS Inc, Chicago, IL, USA) for 9 statistical analysis. The Pearson correlation was adopted to evaluate the relationship among observed rates during 12 months. Value r and their 95% CIs were calculated.
Cochran-Armitage Trend Test was carried out to evaluate the change trend of observed rates. All statistical tests were performed with 2-sided P values. If p value 0.05, the difference was considered statistically significant. parous, and the rate of parous remained unchanged over the 12-month study period according to Cochran-Armitage Trend Test (z=1.076, p=0.300). (Fig 2) Among those 19464 cases, 3869 cases chose NA during labor, but 10 cases failed epidural,

The change trend of episiotomy, operation vaginal delivery, PPH and neonatal asphyxia in women undergoing vaginal delivery
After the implementation of NA in our hospital, the monthly rates of episiotomy, operation vaginal delivery, and PPH and neonatal asphyxia in women undergoing vaginal delivery remained unchanged during 12 months. Moreover, there was no correlation between NA and the rates of episiotomy, operation vaginal delivery, and PPH and neonatal asphyxia in women undergoing vaginal delivery. (Table2, 3)

The change trend of intrapartum CD, PPH and neonatal asphyxia in women undergoing CD
From Table 4,5, it can be found that the monthly rates of intrapartum CD, neonatal asphyxia and PPH in women undergoing CD remain unchanged during 12 months, and there is no correlation between the rate of NA and the rates of intrapartum CD, neonatal asphyxia, and PPH in women undergoing CD (p>0.05).

Discussion
At present, the high CD rate is a social problem in China. However, there are few hospitals conventionally carrying out NA during delivery and labor to meet the needs of parturient women [12] . Many Chinese people think labor pain is normal which is difficult to be avoided for parturient women especially nulliparous, so they choose CD. Under the policy of one-child family taking effect from 1979, wrong cognitions on delivery were prevalent in China, for example they thought the damage caused by episiotomy and that caused by CD were the same, CD might be less likely to affect the quality of sexual life than vaginal birth [13] , and giving birth by selecting a particular date may be more safe [14] . The relative medical indications of CD widely vary all over China, such as pregnancy with severe shortsightedness of eyes, pregnancy by assisted reproduction techniques, primipara more than 35 years old [7,15,16] . Most obstetric centers in China cannot meet the rising expectations of pregnant women, such as lacking the company of family members especially husband, analgesia, or emotional support in labor [3,4] . In recent years, a few Chinese hospitals have started to control the unusually high CD rates with health education, painless delivery, doula delivery and psychological comforting and training programs for midwives and obstetricians [17] . In our birth center, with the help of NPLD program, NA was available for women who requested in to relieve labor pain from May 1, 2015. We observed that the rate of NA also had a good correlation with the rates of overall CD and MRCD There were several reports in the US back in 1990 about the effects of a sudden increase in neuraxial analgesia rate on cesarean delivery rates, with almost all of them showing no effect [18,19] . NPLD is a nongovernment project aiming to help Chinese parturient women and their health care providers about the safe and effective use of NA [7] . According to the data collected from Shijiazhuang Obstetrics and Gynecology Hospital where the project was first introduced in 2008, the rate of overall CD decreased from 40.5% to 33.6% in the period when the rate of neuraxial labor analgesia increased from 0 to 33.5% [20]. Our results are in accordance with those observational studies on the use of NA with the help of NPLD program [7,20] . At the second Affiliated Hospital, Wenzhou Medical University, Wang Q found that as the labor epidural analgesia rate increased from 0 to 57%, the vaginal delivery rate increased, and cesarean delivery rate decreased by 3.5%, at the same time the rate of episiotomy and severe perineal injury were decreased [21] . In our study, with the increase of usage of NA, the rates of overall CD and MRCD were dropped.
At the early implementation stage of NPLD program, the rate of NA was the lowest (26.1%); while the rates of overall CD and MRCD were 50.36% and 10.76% in May 2015, respectively. As the rate of NA increased to 44.6% in April 2016, the rates of overall CD and MRCD decreased to 36.3% and 5.7% respectively. There was a negative correlation between the rate of NA with the rate of CD or MRCD, and there was a positive correlation between the rate of CD and that of MRCD. Our research was consistent with the other's birth center helped by NPLD in China, but inconsistent with that in the US back in 1990.
The difference may be related to China's family policy and the high rate of MRCD.
After implementing "one-child" policy for 30 years, the selective 2-child policy was announced in November 2013, which means that if one of the couples is the only child in her or his family, the couple will have the chance to have two children. China's universal two-child policy was released in October of 2015 [22] . These policies may have an impact on the overall CD rate in China. Liao et al [23] collected data from 6 hospitals in Hubei and Gansu province of China from 2013 to 2016 and found that the overall CD rate decreased from 45.1% during 1-child policy period to 40.4% during selective 2-child policy period, and further to 38.9% during universal 2-child policy period, which is consistent with the results of many other studies [24,25] . Our study period was from May 1st 2015 to April 30th 2016, during which selective 2-child policy period, the family planning policy did not make big influence on the overall CD rate. At the same time, the rate of parous in our study was still around 24.59%, which was not affected by the following universal twochild policy. From those analyses, we believed that the decrease of overall CD rate was mainly related to initiation of labor analgesia services.
Labor pain is probably the most severe pain that most women will endure in their lifetime.
Neuraxial techniques are accepted as the gold standard for intrapartum labor analgesia 13 [26,27] . Ropivacaine has a high threshold for cardiovascular toxicity, and it has been reported that low concentration of ropivacaine is extremely safe and effective for labor delivery analgesia [26,27] . Compared with continuous infusion, intermittent bolus administration of mixed drug of ropivacaine 0.1% with fentanyl 0.0002% provides a more efficacious route of drug delivery without adversely affecting maternal safety or satisfaction [28] . Our clinical trial demonstrated that the NA proposed by NPLD project was effective. For NA, the low concentration of mixed drug of 0.08% ropivacaine plus 2ug/ml fentanyl was effective, in reducing delivery pain from average 9.2 to 3.1 by VAS and NRS.
NA does not increase the risk of CD [7,29] , but its impact on operative vaginal delivery and other parturient safety outcomes is still controversial [30,31] . Anwar S [30] conducted a quasi-experimental study and found that epidural analgesia did prolong the duration of second stage of labor and increased the instrumental delivery rate (58% vs 12%). Wassen MM [31] found the rate of epidural tripled increased from 7.7% to 21.9% over 10 years span while the rates of CD and operation vaginal delivery did not change too much in the Netherlands. This study showed that with the increase of NA rate, the rates of operative vaginal delivery, episiotomy, and PPH and neonatal asphyxia of vaginal delivery, and intrapartum CD, PPH, neonatal asphyxia of CD remained nearly unchanged.

Conclusions
Our study has shown that initiation of a 24-hour labor analgesia services can have benefits beyond simply pain relief, as critical as pain relief itself can be, the rates of CD        Cochran-Armitage Trend Test (z=1.076, p=0.300).

Figure 3
The results of Cochran-Armitage testing