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 Table of Contents  
ORIGINAL ARTICLE
Year : 2019  |  Volume : 6  |  Issue : 1  |  Page : 119-124

General versus spinal anesthesia during elective cesarean section in term low-risk pregnancy as regards maternal and neonatal outcomes: a prospective, controlled clinical trial


1 Department of Obstetrics & Gynecology, Zagazig University, Zagazig, Egypt
2 Department of Anesthesia and Surgical ICU, Zagazig University, Zagazig, Egypt

Date of Submission10-Dec-2017
Date of Acceptance09-Jan-2018
Date of Web Publication27-Feb-2019

Correspondence Address:
Nadia M Madkour
Department of Obstetrics & Gynecology, Zagazig University, Zagazig, 35842
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/roaic.roaic_104_17

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  Abstract 

Objective The objective of this study was to compare general and spinal anesthesia as regards its maternal and neonatal outcomes in low-risk pregnancies undergoing elective cesarean section (C-section) at term.
Patients and methods In a prospective, controlled clinical trial, 64 low-risk pregnant women underwent elective C-section for the first time for variant indications. The included women were randomly divided into two groups; group I (n=32) received spinal anesthesia and group II (n=32) received general anesthesia. The distinction between preoperative and postoperative maternal hematological indices, intraoperative and postoperative maternal hemodynamic parameters, the maternal requirement for analgesia, return of bowel function, and neonatal outcomes were compared between the two groups.
Results The mean time for bowel to be open (9.7±1.3 vs. 6.8±1.6 h, P=0.001), and the first analgesia requirement was significantly (5.33±4 vs. 2.91±2.16 h, P=0.004) longer, and the hemoglobin and hematocrit difference values at 24 h postoperative were significantly (P=0.03, and 0.02, respectively) larger in group II. Urine output at the first postoperative hour was more (P=0.002) in the spinal group. The median Apgar scores at the first minute and at fifth minute were significantly higher (P=0.001, and 0.005, respectively) in the spinal group.
Conclusion As long as it is not contraindicated, spinal anesthesia during elective C-section was safer for both neonates (higher Apgar scores), and mother (less bleeding, less postoperative pain) than general anesthesia and can be the ideal anesthesia and method of choice during elective C-section.

Keywords: anesthesia, cesarean section, general, maternal, neonatal, spinal


How to cite this article:
Madkour NM, Ibrahim SA, Ezz GF. General versus spinal anesthesia during elective cesarean section in term low-risk pregnancy as regards maternal and neonatal outcomes: a prospective, controlled clinical trial. Res Opin Anesth Intensive Care 2019;6:119-24

How to cite this URL:
Madkour NM, Ibrahim SA, Ezz GF. General versus spinal anesthesia during elective cesarean section in term low-risk pregnancy as regards maternal and neonatal outcomes: a prospective, controlled clinical trial. Res Opin Anesth Intensive Care [serial online] 2019 [cited 2020 May 31];6:119-24. Available from: http://www.roaic.eg.net/text.asp?2019/6/1/119/253113


  Introduction Top


The cesarean section (C-section) is the most frequent surgical procedure in obstetrics and gynecology. It is the route of delivery in ∼30% of live births [1]. As C-section deliveries frequency rises all over the world, and although it has become safer than before, it is still associated with higher maternal and perinatal mortality and morbidity than vaginal deliveries [2]. This higher mortality and morbidity rates are not only because of the surgical procedure but also related are to the anesthesia used. Cesarean anesthesia has gained importance as its frequency has increased, but is still under discussion and choosing the spinal or general anesthesia also has many controversies as regards its maternal and neonatal safety [3]. The choice of anesthesia depends on the mother’s request, obstetric indications, and on the anesthesiologist’s experience level. For many years, general anesthesia was the preferred one in a C-section [4]. The rates of the C-section using regional anesthesia have been increasing aiming to avoid fetal exposure to depressant medications and to allow the mother to stay awake during labor [5], and then became the preferred anesthetic technique by many anesthesiologists in elective conditions [6]. Still now, no optimal cesarean technique or ideal and standard anesthesia method for reducing maternal and perinatal morbidity has yet been described in the literature. Our aim was to compare the general and spinal anesthesia as regards maternal and fetal outcomes in women undergoing elective C-section for the first time at term to identify an ideal anesthetic method to decrease both maternal and perinatal morbidity and mortality related to anesthesia.


  Patients and methods Top


A prospective, controlled clinical trial carried out on 64 low-risk pregnant women, full-term (37–40 weeks gestation), singleton, cephalic presentation, and who were scheduled for elective C-section for the first time, at Zagazig University Hospital (tertiary hospital) were recruited between January 2016 and October 2016 after approval by the ethics committee/institutional review board provisions of Zagazig University. Signed informed consent was collected from all included women. Women who were requiring emergency C-section for delivery, previous C-section or laparotomy, have high-risk pregnancy (e.g. hypertensive disorders, cardiac disorders, or blood diseases), BMI of at least 30 kg/m2, fetal abnormalities (fetal anomaly, multiple gestations, macrosomia: ≥4500 g, polyhydramnios: amniotic fluid index>25 cm, oligohydramnios: amniotic fluid index<5 cm, intrauterine growth restriction; birth weight to SDs below the population mean for gestational age and sex), and/or placental abnormalities, such as placental abruption, placenta previa, or abnormal adherent placenta were excluded from the research. Dating of pregnancy was based on sure last menstrual period and/or early pregnancy ultrasound examination. Preoperative evaluation for all cases included full history, physical examination and laboratory investigations [hemoglobin (Hb) level, platelet count, random blood glucose, liver function tests, prothrombin time and international normalized ratio, prothrombin concentration, urea, and creatinine]. Preoperative medications included H2-blocker 50 mg, and metoclopramide 10 mg intravenously. Patients’ basic demographic information was recorded in a study information sheet. All included women were classified randomly into two groups: group I (n=32) undergo C-section under spinal anesthesia and group II (n=32) undergo C-section under general anesthesia.

General anesthesia

Preoperative setup: patients should be preferably laid in the left lateral decubitus position until placed supine on the operating table with a left uterine displacement. Intraoperative positioning: Patients should be placed supine on the operating table with left uterine displacement; the operating table should have a left lateral tilt of 15°. Standard general monitoring should be placed before the induction of anesthesia including ECG, noninvasive blood pressure, pulse oximetry, bladder catheterization planning, and assistance availability. In addition to the preparation and monitoring of the mother, the neonatal resuscitation team was prepared to receive and care for the newborn; all equipment for resuscitation was present simultaneously with the presence of powerful suction. To reduce the time between anesthesia induction and delivery, the patient’s abdomen was prepared and draped before initiation of general anesthesia. Intravenous wide-pore catheter was inserted 18 G with slow infusion of lactated Ringer’s solution, and preinduction oxygenation with100% O2 for 3–5 min. Rapid-sequence crash induction was done with cricoid pressure by our skilled assistant with the insertion of endotracheal tube sized 7–7.5; the induction was done by using thiopentone (5–7 mg/kg), succinylcholine 1.5 mg/kg. Anesthesia was maintained using isoflurane 0.75%, N2O : O2 (5–5) to ventilate the lungs to maintain an end-tidal CO2 concentration of 32 mmHg. For further muscle relaxation, atracurium was given in a dose of 0.1 mg/kg every 20 min after delivery of the baby. Fentanyl was given in a dose of 1–2 ml/kg. Isoflurane adjusted to a maintained end-tidal CO2 concentration of 0.3 and 70% nitrous in oxygen. At the end of surgery, neostigmine and atopine was given in a dose of 0.08 and 0.1 mg/kg, respectively. Nitrous was stopped and oxygen concentration was raised to 100%; the gastric tube was inserted to decrease the risk of aspiration on an emergency. Blood loss was assessed. Anesthesia gastric tube was removed and awake extubation was performed.

Spinal anesthesia

All parturients were infused with 1000–1500 ml of Ringer’s lactated solution through an 18-G intravenous cannula over a period of 15 min before induction. All equipment and medications should be checked. Full resuscitation facilities were present as well as standard patient monitoring [ECG, noninvasive blood pressure and oxygen saturation (SpO2) as a minimum]. Aseptic technique was employed, sterilization using povidone-iodine solution, with infiltration of local anesthetic 1 ml xilocaine 10%. Spinal needle was inserted (anesthesia was achieved by intrathecal injection of 2.4 ml hyperbaric 0.5% bupivacaine and 20 µg of fentanyl through a 25-G pencil point needle). All patients were monitored with noninvasive blood pressure, pulse oximeter, ECG, intravenous fluids 1.5 ml/kg, and ephedrine was administered in 3 mg increments as required to support blood pressure if hypotension (mean arterial blood pressure falling below 60 mmHg) occurs together with fluids. Atropine in a dose of 0.1 mgl/kg was given for bradycardia [heart rate (HR) falls below 50 beats/min], and pethidine 30 mg for shivering. In case of SpO2 lower than 90%, 100% O2 was administered at a rate of 4 l/m, through a face mask.

After applying the respective anesthesia to the groups, a standard lower-segment transverse uterine incision was made. The placenta was removed manually. All the cesarean deliveries were performed by a single expert, MD, a surgical obstetrician. After delivery of the baby and the placenta (removed manually), all patients received 0.2 mg/ml of ergometrine (methergine) intramuscularly, 1 g of prophylactic second-generation cephalosporin intravenous and 20 U of oxytocin on 500 ml intravenous drip at a rate of 125 ml/h. With the closure of uterine incision in a double layer, continuous suturing with a 1-0 polyglycolic acid suture (Vicryl; Ethicon), and layers of visceral peritoneum were brought together. In group II, when the skin closure began, 0.5 mg/kg of tramadol HCl was administered intravenously. The duration of the operation, from beginning the skin incision to applying the last skin closure suture, was recorded. The newborn assessment was done by a single, senior pediatrician in the operating room. All newborns were attended at the delivery room by a single, senior pediatrician who was blind to the anesthetic technique used. Newborn’s information: its sex, birth weight, first and fifth minute Apgar scores, medications given, the need and indications for incubation were recorded. After complete recovery from anesthesia, the postoperative treatment was the same for each group. All patients were monitored for the first hour: systolic blood pressure, diastolic blood pressure, mean arterial blood pressure, HR, peripheral SpO2, and urine output volume (ml) were recorded. The severity of postoperative pain was assessed using the verbal rating scale (VRS): 0=no pain and 10=the worst pain [7]. When VRS was 4 or more, 75 mg of diclofenac sodium (Voltaren) was given intramuscularly. Then, whenever VRS was at least 4, analgesic was given. The time (h) at which the first dose of analgesic was required and the total number of doses administered within the first, 24 postoperative hours were recorded. A measure of 3 l of intravenous fluid containing oxytocin (10 IU/l) over the first 24 h was given postoperatively. Patients were mobilized 6 h postoperative and were allowed for oral liquid intake. Then aqueous food intake was allowed after the return of gastrointestinal functions. The time that elapsed until postoperative bowel action (auscultation of bowel sounds and/or gas discharge) was calculated (h). Body temperature measurements (°C) (every 4 h over the first 24 postoperative hours) were recorded. Hb (g/dl) and hematocrit (Hct, the fraction of blood, i.e. red blood cells) values (%) were determined both before and at the 24th hour postoperatively. Blood loss (ml)=blood volume (ml)×(initial hematocrit−final hematocrit). Hcts were measured as percentage (from 0 to 100%). Blood volume=Weight×average blood volume (65/kg for women) [8].

Statistical analyses

Statistical analyses were performed using SPSS (SPSS Inc., Chicago, Illinois, USA) and described as the mean, SD, frequency, and percentage. Student’s t-test was used for continuous variables and the χ2-test for categorical variables. Statistical significance was defined as P value less than 0.05 formed using the statistical package for social sciences 15.0 software for Windows.


  Result Top


Sixty-four pregnant women with term, singleton, cephalic, of low-risk pregnancy, and undergone elective C-section for the first time were included. Their mean ages were: 26.4±4.3 years, range: 19–34 years. Mean BMI: 26.2±2.5, range: 20.6–30. The mean gestational age in weeks was: 38.4±0.7 (37–40). Gravidity ranged 1–5, and parity ranged 0–3. There was no statistically significant difference (P>0.05) as regards maternal age, gestational age, BMI, gravidity, parity, duration of surgery between spinal and general anesthesia groups, and preoperative and postoperative Hb levels (P=0.3 and 0.09, respectively), and Hct value (P=0.3 and 0.8, respectively), intraoperative or postoperative HR (P=0.6 and 0.2, respectively), postoperative: diastolic blood pressure (P=0.7), SpO2 (P=0.07), and temperature (P=0.4). The mean 24th postoperative Hb level (10.1±06 vs. 9.9±0.7 g/dl) and Hct values (33.4±2.3 vs. 33.3±2.4%, P=0.09 and 0.8, respectively) in group I versus II, whereas the 24th hour Hb difference values (1.02±0.1 vs. 1.5±0.2 g/dl) (P=0.03) and Hct difference values (1.4-6.1 vs. 2.7–6.3%, P=0.02) were higher in the general anesthesia group. The first postoperative hour urine output volume (P=0.002) was higher in the spinal group. Mean time until bowel to be opened (6.8±1.6 vs. 9.7±1.3 h, P=0.001), and the first requirement for analgesia was significantly (5.33±4 vs. 2.91±2.16 h, P=0.004) greater in group II. Also, the total dose of analgesia needed was more in the general anesthesia group (P=0.001). As regards neonatal outcome, the Apgar score at the first and fifth minutes was higher in the spinal group (5–9 vs. 4–7, 6–10 vs. 5–9, P=0.001, and 0.005, respectively). Meconium staining (1 vs. 10) and pediatric clinic attendance (1 vs. 7) were more frequent in the general group. But there was no significant difference as regards the neonatal birth weight, and/or the need for neonatal incubation (P=0.2) for either meconium aspiration and/or respiratory distress ([Table 1],[Table 2],[Table 3],[Table 4]).
Table 1 Demographic data of the studied groups

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Table 2 Preoperative, during, and postoperative maternal hemodynamics in both groups

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Table 3 Postoperative maternal general condition

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Table 4 Neonatal outcome in both groups

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  Discussion Top


Although the steady rise in the rate of cesarean delivery still carries a higher maternal and neonatal morbidity and mortality which is not related to surgical skills alone but also to the anesthesia used [9], and still there is no single ideal surgical technique or anesthetic method to be used in C-section [7]. Both experience and trends are shifted toward spinal anesthesia [10].

Our aim was to compare spinal anesthesia to general anesthesia as regards their maternal and neonatal outcomes in elective C-section.

The intraoperative systolic and diastolic blood pressure was not significantly different between spinal and general anesthesia. This could be explained by the preoperative hydration with 1000 ml of colloid solution. However, intraoperative hypotension occurred in 26% of spinal cases in a study by Saygı et al. [7], and in a higher frequency with Kavak et al. [11] and Gogarten [12]. Abdallah et al. [13] found a higher incidence of intraoperative tachycardia with general anesthesia patients compared with combined spinal–epidural anesthesia patients and they attributed this to the stress of rapid-sequence induction and inadequate analgesic drugs which was postponed till delivery of the fetus. We used Bourke and Smith equation [8] which is one of the common formulae to calculate the intraoperative blood loss using preoperative and 24th hour postoperative Hct values. Intraoperative blood loss was significantly less (P=0.02) in spinal (−60 ml) than in general anesthesia that agreed with Afolabi and Lesi [14] and Martin et al. [15]. Two clinical trials [16],[17] and one meta-analysis [14] noticed that intraoperative bleeding was less with spinal anesthesia (−0.59 ml) than with general anesthesia and could be interpreted by the fact that agents used in general anesthesia interfere with uterine contractions and/or impair platelets function and hemostasis. Also, factors that can affect intraoperative blood loss, for example, maternal weight, parity, previous C-section, fetal causes, multiple gestations, polyhydramnios, malpresentation, and/or operative technique were excluded from our study. The postoperative pain was less in spinal anesthesia, lower visual analog scale scores, and longer elapsed time (320±240 min in spinal vs. 175±130 min in general) for the first analgesia requirement. Hong et al. [16] found the time for the first dose of analgesia was 690 min (spinal) versus 190 min in the general anesthesia group), and in a research by Saygı et al. [7] was 185±340 min (general) versus 340±401 min (spinal). Dyer et al. [17] found that the visual analog scale scores were 54 mm [spinal vs. 72 mm (general), P<0.001]. In contrast, Fassoulaki et al. [18] found higher scores among the neuraxial anesthesia patients (77 vs. 52 with general anesthesia, P=0.001). The time elapsed till bowel to be opened (audible sounds and/or passage of gases) was significantly longer in general anesthesia (9.7±1.3 vs. 6.8±1.6 h) than spinal, and was identical to Saygı et al. [7], who found the values to be 11.35±5.8 h in general vs.8.9±5.3 h in spinal; P=0.036. First and fifth minute Apgar scores were significantly higher in spinal anesthesia than in general type, first (7.6±1.1 vs. 5.9±0.8), fifth (9.2±0.8 vs. 8.4±1.1), which could be explained by the fact that although there was higher prevalence of maternal hypotension during spinal anesthesia, this was avoided by prehydration with 1000 ml colloid, and the fact that full-term newborns can tolerate the hypotensive effect on placental blood supply. In addition to the transient sedative effect of general anesthesia agents on neonates Mancuso et al. [19] found 25.9% of neonates were with first minute Apgar scores less than 7 at 1 min in general anesthesia group and 1.1% for the spinal anesthesia group (P<0.001); however, after 5 min, all neonates had a score of more than 9, and 14% of neonates in general anesthesia versus 0% in spinal group were requiring oxygen or positive pressure ventilation, but found no difference in the umbilical arterial pH in elective C-section, and none required tracheal intubation or ICU. He concluded that spinal anesthesia was superior to general anesthesia in neonatal outcome. Although, Korkmaz et al. [20] found no differences in the 1- and 5-min Apgar scores, when comparing spinal anesthesia versus general anesthesia even the umbilical artery pH was significantly lower in spinal anesthesia patients as compared with general anesthesia in studies by Dyer et al. [17], Petropoulos et al. [21], and Reynolds and Seed [22] who performed a meta-analysis on different types of anesthesia and they concluded that spinal anesthesia cannot be considered safer than epidural or general anesthesia for the fetus.


  Conclusion Top


As long as it is not contraindicated, spinal anesthesia during elective C-section was safer for both neonates (higher Apgar scores) and mother (less bleeding, less postoperative pain) than general anesthesia and can be the ideal anesthesia and method of choice during elective C-section.

Acknowledgements

The authors thank all included women for their valuable contribution in this work.

Financial support and sponsorship

Nil.

Conflicts of Interest

There are no conflicts of interest.

 
  References Top

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Bourke DL, Smith TC. Estimating allowable hemodilution. Anesthesiology 1974; 41:609–611.  Back to cited text no. 8
    
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Kavak ZN, Başgül A, Ceyhan N. Short-term outcome of newborn infants: spinal versus general anesthesia for elective cesarean section. Eur J Obstet Gynecol Reprod Biol 2001; 100:50–54.  Back to cited text no. 11
    
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Afolabi BB, Lesi FE. Regional versus general anesthesia for caesarean section. Cochrane Database Syst Rev 2012; 10:CD004350.  Back to cited text no. 14
    
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Mancuso A, de Vivo A, Giacobbe A, Priola V, Maggio Savasta L, Guzzo M, Mancuso A. General versus spinal anesthesia for elective caesarean sections: effects on neonatal short-term outcome: a prospective randomized study. J Matern Fetal Neonatal Med 2010; 23:1114–1118.  Back to cited text no. 19
    
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