Prevalence of Pain During Cesarean Section

Pain during cesarean section and its poor perception can lead to serious psychological consequences for the woman experiencing pain. The topic has also been discussed in the media, which has caused stress for women in labor. A recent meta-analysis on the subject suggested that 14% of women in labor reported pain when using spinal anesthesia and 33% with epidural anesthesia. The reported difference is understandable - spinal anesthesia is used for surgery using a stronger anesthetic system, while epidural anesthesia is used for emergency cesarean section during labor.

By combining spinal and epidural anesthesia, it is theoretically possible to achieve the advantages of both spinal anesthesia (rapid and intensive anesthesia) and epidural anesthesia (possibility to continue anesthesia). Surprisingly, the meta-analysis showed that the incidence of pain with CSE anesthesia, which combines spinal-epidural anesthesia, would exceed that during spinal anesthesia alone with a reported perioperative pain rate of 18 %. It was speculated that combined anesthesia would be used mainly in complicated cases, where it is suspected from the start that the procedure will be prolonged. In a European multicenter study published this year, CSE anesthesia was used in only 10% of planned cesarean sections, and even of these cases in the data, about a third were performed in Finland.

Combined spinal-epidural anesthesia (CSE anesthesia) is widely used in Finland, for example at the HUS Women's Clinic, Oulu University Hospital and Kuopio University Hospital, especially when performing anesthesia for planned cesarean sections.

In this prospective cohort study, we will investigate the incidence of patient reported pain during planned cesarean section in three university hospitals in Finland using CSE anesthesia. 200 parturient women undergoing planned cesarean section will be recruited. Additionally the quality of recovery after the elective cesarean section will be monitored by QoR -15 questionnaire up to 30 days after the operation for those participants whose cesarean delivery is performed in Oulu or Kuopio centers.

The study will investigate the prevalence and severity of pain during cesarean section in Finland. The primary outcome of the study is the proportion of parturient women who report experiencing pain during surgery, defined as the highest pain NRS value for pain during surgery reported by the parturient immediately after surgery being 4/10 or more (0=no pain and 10=worst possible pain) or the parturient reporting an answer other than "none" to the question "I have experienced pain during surgery" on the questionnaire. Based on the power calculation, the study requires 157 parturient women to reliably determine (a=0.05; b=0.20) the expected incidence of pain in our data (10%) compared to the reported incidence of pain with CSE anesthesia (18%). As a secondary outcome variable, we will investigate which patient, surgical and anesthesia-dependent factors are associated with pain during surgery.

In the study, an assessment of the success of anesthesia from the anesthesiologist (prevalence and intensity of pain), as well as the method used to test the anesthesia and the level of numbness observed, will be collected using an interview form. For the analysis of the primary outcome variable, an assessment of the nausea, discomfort and pain experienced by the parturient woman (intensity, duration) will be collected in the recovery room after the procedure. After the subject has completed the assessment form, she will close it in an envelope and the staff treating her will not know the answers. In addition, the following background information is collected from the study subjects from the information system: previous pregnancies (number), previous caesarean sections (number), height and weight of the mother, age of the mother (years); duration of pregnancy (weeks); long-term illnesses; smoking; fear of childbirth diagnosis (if established before the day of the procedure); duration of the operation (minutes); hemorrhage (millilitres); lumbar interspace in the spine (used for anesthesia); number of attempts to perform the anestehsia; paresthesias; spinal anesthesia (type and dose); level of experience of the anesthetist (non-specialist vs. specialist); additional medications (sedatives and analgesics) during the procedure, general anesthesia (yes/no). Quality of recovery is followed using QoR-15 questionnaire before ward transfer at the recovery room, before discharge from hospital and 7, 14 and 30 days after surgery. This will be performed to patients operated in Kuopio and Oulu University hospital.

Pain during caesarean section and unresponsiveness to it cause considerable harm to the patient, can lead to post-traumatic stress disorder, thinking about whether to have more children, and postpartum depression. For the hospital, these painful experiences and the subsequent investigations and complaint processes that arise from them place a strain on the anaesthetists working in the surgical unit. This study provides additional information on the functionality of the form of anaesthesia commonly used in caesarean sections in Finland under Finnish conditions, and based on its results, it can be assessed whether operating instructions or patient information should be changed or improved.