The World Health Organization (WHO) [1] defines maternal mortality as the death of a woman occurring during pregnancy or within 42 days of its termination regardless of its duration or location, for any cause determined or aggravated by the pregnancy or the care it motivated. There is no standardized definition of maternal morbidity. It has been proposed to define severe morbidity concerning the main obstetric emergencies as the set of complications requiring urgent medical intervention to avoid maternal death [2]. We defined maternal anesthetic morbidity and mortality when the cause of which is directly related to the anesthetic act. According to the WHO report [3], 300,000 maternal deaths are recorded each year around the world, 99% of which come from low and middle income countries. Morbidity linked to complications in pregnancy, childbirth and postpartum affects approximately 9% to 15% of parturients and remains difficult to measure because it depends on the quality of available care and the information system. In 2019, the WHO [4] estimated that around 830 women die worldwide every day from complications related to pregnancy or childbirth. Anesthesia for cesarean section is characterized by the need to ensure safety for the mother-child pair and the risk of maternal morbidity and mortality is not zero given the physiological changes in pregnancy, the indication for cesarean section and maternal state [5]. The maternal anesthesia-related mortality rate is low in high-income countries [6] [7] [8], 14.8 per 100,000 caesarean sections in South Africa, a contribution of 2.4% to overall mortality [9], in Nigeria out of 5.6 deaths per 1000 cesarean sections, 6 were related to anesthesia [10]. Maternal morbidity for planned cesarean section in Japan between 2010 and 2013 was 2% under general anesthesia (GA) and 0.7% under locoregional anesthesia (LRA) [11]. This morbidity increased from 0.74% to 1.29%, between 1998 and 1999 to 2008 and 2009 in the USA [7]. It doubled in LRA and decreased in GA in Germany [8]. In low- and middle-income countries, the risk of dying for a woman who underwent cesarean section is 1.2/1000. Anesthesia accounts for 2.8% [2.4 - 3.4] of all maternal deaths, 3.5% of all direct maternal deaths, and 13.8% of deaths after cesarean section [12]. In the Democratic Republic of Congo (DRC), with a maternal mortality rate of 690 per 100,000 live births in 2015 [13], there are no data on maternal morbidity and mortality related to anesthesia. This study was conducted with the objective of investigating the determinants of maternal mortality and morbidity related to anesthesia during cesarean section in a low-income setting.

Type of study: It is a prospective, analytical and one-center study. The population consisted of all women who underwent cesarean section at the Mère-Enfant MONKOLE Hospital (MEMH) from 1/1/2011 to 31/12/2018. The MEMH is a level II hospital, acting as the general referral hospital of the urban-rural health zone of Mont Ngafula I.

Patients selection: All women anesthetized and caesarized at the MEMH during the study period were included. Those operated secondarily after vaginal delivery was not included. An electronic file containing the data of women who underwent cesarean section has been drawn up and the women recruited exhaustively and consecutively. The vital outcome was assessed until the first postnatal appointment, six weeks after cesarean section. The variables collected were: Sociodemographic variables: age (divided into three: <18 years old, between 18 and 35 years old and over 35 years old), the body mass index (BMI) in kg/m². Obstetric variables: the place for prenatal consultation (MEMH or referred); parity grouped into 4: primiparous (one childbirth), pauciparous (2 to 3 childbirths) multiparous (4 to 6 childbirths) and large multiparous (more than six childbirths); fundal height and indications for cesarean section grouped into three according to the degree of emergency: extreme emergency (immediate action: <5 to 15 minutes), absolute emergency (action <30 minutes) and relative emergency (action >30 minutes). Clinical variables: Glasgow coma score, anesthetic risk according to the American Society of Anesthesiologists (ASA) classification before the 2020 revision and Cormack and Lehanne’s grade. Biological variables: hemoglobin level grouped into three: severe anemia (<7 g/dl), moderate (7 to 10.9 g/dl) and normal (11 g/dl and more) and platelet count. Intraoperative variables: anesthetic technique, intraoperative complications (an anesthetic complication is one that can only be linked to anesthetic products or technique), intraoperative transfusion, operative procedures performed (cesarean section alone and or another act), qualification of the interveners (senior or junior), degree of emergency and time of intervention (day: 8:00 a.m. to 5:00 p.m. or night: 5:00 p.m. to 8:00 a.m. and public holidays). Postoperative complications, maternal outcome, and determinants of morbidity and mortality were investigated. The definition of maternal death was that of the WHO [1] but only in the context of cesarean section.

Statistical analysis: Data were entered into an Excel file, coded, analyzed with SPSS 21.0 and presented as frequency and mean. The comparison of the variables was made with the Student’s t test or Chi-square or Fischer’s exact test. Determinants of mortality were sought using the logistic regression test. The odds ratios and their confidence intervals were used to establish the degree of association. The p-value was set to <0.05.

Ethical considerations: The approval of the CEFA/MONKOLE ethics committee has been obtained (letter N/ref: 004 CEFA-MONKOLE/CEL/2020). The principles of anonymity and confidentiality of the Helsinki Convention have been respected during all data collection and processing processes and informed consent obtained.

During this period, 1954 cesarean sections were performed out of 6720 registered deliveries, a rate of 29%.

Our study, although mono-centric, includes a population fairly representative of the local context with regard to age groups with a majority between 18 and 35 years (75.53%), few women were obese (13.2%), non-negligible rate of women referred from primary structures (20.7%), the relatively high emergency cesarean section rate (32.6%), on the other hand the qualification of the interveners differs from what happens in the majority of hospitals in the low income countries [14]. The cesarean rate in our series was 29%. A study led by WHO [14] reports that between 1990 and 2014, the global average rate of cesarean section fell from 12.4% to 18.6% with rates varying according to the regions, between 6 and 27.2%, and increasing at an average rate of 4.4% per year. This increase was slight but real in sub-Saharan Africa during the same period. This is the case in our institution, where the rate fell from 15% in 2005 to 29% in 2018 when it became a general referral hospital. The overall mortality in our series was 0.56% and with no cases attributable to anesthesia. The determinants of maternal mortality in multivariate analysis were: extreme emergency, coma on admission, general anesthesia and intraoperative transfusion. In a multicenter study that included 2,933,457 cesarean sections in 59 countries, Sobhy [15] found 8 maternal deaths in 1000 women (0.8%) in the low- and middle-income country. Our mortality is lower, perhaps because of the qualifications of the interveners and the internal organization of the hospital allowing rapid treatment of emergencies. Maternal mortality in South Africa was 18.9 deaths per 10,000 caesarean sections and 14.8 deaths were related to anesthesia which contributed to 2.4% of the maternal mortality rate [9]. Our overall rate exceeds that of South Africa even though no death was attributed to anesthesia in our series. This shows the disparities between countries. In our series, the average age of women is 31.01 years old, close to Trabelsi [16] in Tunisia (30.2 years) and the majority (75.53%) are between 18 and 35 years old, results different from Beye [17] in Mali (15 to 25 years old), with a different grouping from ours. Although maternal age beyond 35 increases the obstetric risk, our results do not show excess mortality in this age group. A fairly recent review of the literature had shown that the causes of maternal death in adolescents and elderly women are the same in low-income countries [18], which corroborates our results.

We recorded 81.83% of maternal deaths among the referred women (PNC outside the MEMH). In fact, a significant number of them had either not followed the PNC at all or had followed it poorly. This explains the very high mortality described by other authors [19] [20] [21]. In addition, these referred women arrived at the hospital either on foot, on a motorbike or car, but never with an ambulance. Although performing LRA in obesity conditions is difficult [22], we had neither failure nor insufficiency of obesity-related block, probably because we had no cases of morbid obesity [23]. We did not record excess mortality in women who had multiple cesarean sections, but relatively more intraoperative bleeding as Hyginus [24] found. Maternal mortality is very high during an extremely emergency cesarean section (45.5% of deaths), which corroborates the data in the literature [25]. We observed that a uterine height greater than 34cm was accompanied by arterial hypotension (32.5% versus 23.7%) suggesting aorto-caval compression by the uterus as described in the literature [26]. Our results show that the mortality in ASA IV patients is very high (72% of deaths) confirming the relationship between the ASA class and mortality [27]. Although the pregnant woman is considered difficult to intubate [26], no cases of difficult intubation or inhalation in the 143 women who underwent general anesthesia were recorded. Trabelsi [16] reported 0.21% difficult intubation in his series with a general anesthesia rate higher than ours. However, some authors have underlined that this difficult intubation 5 to 8 times than the non-pregnant woman remains rare as in their series [28] [29]. Although the platelet count was not taken in some women who received LRA, no cases of peri-medullary hematoma were recorded as Bloom found (0%) in 14,797 patients. [27] Nine out of 11 deaths, 81.8% occurred during GA which has emerged as a major determinant of maternal death. However, the pathologies presented by women operated on under GA were not only indications of general anesthesia but also factors of maternal mortality (eclampsia, uterine rupture, hemorrhagic placenta previa). Bloom in 2005, for example, found that 38% of general anesthesia was performed for emergencies [27]. All of the participants were doctors, unlike the other African series, and their qualification did not influence mortality [30] [31]. Mortality is higher in emergency surgery: 90.9%, vs regulated surgery: 9.1% (p < 0.001). This deleterious role of emergency has been found by other authors [32]. Arterial hypotension without maternal-fetal consequences because treated quickly was the most frequent complication due to the justified use of spinal anesthesia [33]. The rate of intraoperative maternal incidents in our series is 32.2%, higher than those reported by other authors due to the different understanding of intraoperative incidents [34] [35]. Typical anesthetic complications accounted for 3% as Bloom [27] had found: one in 29 deaths. We recorded 0.15% of uretero-vesical lesions, unlike Onsrud [36] who, in eastern DRC where insecurity reigns, found that 25% of all fistulas treated were caused by cesarean section, but in the context of rape. The overall mortality was 0.56% in our study (no anesthesia-related deaths), lower than the 1% found by Fenton [37] in Malawi. Ouro-Bang’na Maman AF [38] estimates that mortality linked to anesthesia in general is more than 4 times in Togo. This mortality rate varies from country to country and from hospital to hospital, from 0.87% to 3.88% [12]. Bleeding is an important part, as other authors have noted [15] [39] [40]. A WHO-led study [41] had shown the role of hemorrhage (26.7%) and pre-eclampsia (25.9%) in maternal mortality as we have found. Our hysterectomy rate is high: 0.32% more than Trabelsi [16] 0.07% and this is associated with significant mortality because these were the women referred with uterine rupture in a state of persistent hemorrhagic shock. The lack of technical facilities for arterio embolization made hysterectomy the only maternal lifesaving solution [42]. Haemorrhages (uterine rupture, DPPNI, placenta previa) and preeclampsia are still the major causes of maternal mortality as found by several authors [43] [44] [45].

The limits of this study lie in its monocentric nature, which does not allow the results to be generalized over the entire city of Kinshasa or the whole country.

The overall maternal mortality in this series was 0.56%. No maternal deaths related to anesthesia, either general or locoregional, have been recorded. Maternal morbidity is low and represented mainly by intraoperative hypotension without consequences. Uterine rupture, hemorrhagic placenta previa and eclampsia are major causes of maternal death.

In multivariate analysis: general anesthesia, extreme emergency, intraoperative transfusion and coma persisted as determinants of mortality in this series. However, general anesthesia as well as blood transfusion is a consequence of the severe maternal condition, often hemorrhagic shock contraindicating the realization of a locoregional anesthesia and imposing and general anesthesia and blood transfusion. Bleeding appears to be an important element that must be acted upon to reduce maternal mortality, as it is decried throughout the literature. In perspective, a provincial or national multicenter study would be useful to have a more precise idea of the situation in our country.

We would like to thank the operating theater and maternity teams of the Mère-Enfant Monkole Hospital and Milka Mbuyi Mbombo (for helping on traduction).

WMD: design and writing of the manuscript, NKM: writing of the manuscript, ANN: statistical analyzes and correction of the manuscript, LTM: correction of the manuscript, all other authors: reading of the manuscript.

The authors declare no conflicts of interest regarding the publication of this paper.

Dibue, W.M., Muanza, N.K., Nganzele, A.M., Mukishi, F.M.W., Natuhorila, A.N., Mbamba, C.T., Lokakao, S.B., Nyani, M.M., Ngwangi, H.M., Lukusa, F.Z., Badianyama, R.K., Kambala, R.L., Manzanza, A.K., Nsimire, B.B. and Muepu, L.T. (2022) Determinants of Maternal Morbidity and Mortality Related to Anesthesia in Course of Cesarean Section in a Low-Income Country: Experience from the Centre Hospitalier Mère- Enfant Monkole. Open Journal of Anesthesiology, 12, 168-183. https://doi.org/10.4236/ojanes.2022.125015

Data collection sheet