Retrospective study of maternal mortality in a tertiary hospital in Egypt.

BACKGROUND: Making efforts to decrease maternal mortality rate is a moral, economic and human rights related issue. This issue could not be handled without investigation of maternal mortality related factors. The role of anesthesia in maternal mortality in developing countries is obscure. The aim of the study is to estimate the prevalence, causes and risk factors of maternal mortality related to anesthesia. PATIENTS AND METHODS: An observational retrospective study was carried out in our university hospital from January 2004 till December 2008.
RESULTS: The study revealed that maternal mean age of death was 34.9 years, 59% of women came from rural areas and 41% from urban ones, 65% delivered inside the hospital while 35% delivered outside, 71% were multiparous, 65% had no antenatal care and 29.7% irregular one, 12% were complaining of concomitant diseases, 77.5% labored with cesarean section, 17% died before labor, 36% during and 47% after labor. Causes of death are given in the order of the most leading cause of death to the least as follows: postpartum hemorrhage, eclampsia, pre-eclampsia, postpartum eclampsia, ruptured uterus, amniotic fluid embolism, accidental hemorrhage, anesthesia and at last unexplained causes.
CONCLUSIONS: Maternal mortality was 953 per 100,000 cases and the greatest number of deaths took place among women considered to be at low risk. Anesthesia was responsible for about 8% of the causes of death. Difficult airway management during general anesthesia was the major anesthetic reason for maternal mortality.

INTRODUCTION

Maternal mortality is considered a basic health indicator that reflects the adequacy of health care.[1] Despite numerous improvements in health care, poor outcome in the parturient remains a major public health concern that follows us into the 21st century.[2]

In 2005, an estimated 536,000 women died of maternal causes worldwide of which 86% occurred in sub-Saharan Africa and South Asia and less than 1% in more developed countries. The large regional differences in maternal deaths demonstrate that many of these deaths are preventable.[3]

Maternal mortality related to anesthesia is low compared with that resulting from obstetric factors in developed countries.[4] The role of anesthesia in maternal mortality in developing countries is obscure. The purposes of this study were to determine the incidence of maternal mortality related to anesthesia, to analyze the causes and to suggest measures to improve anesthetic safety for parturient.

MATERIALS AND METHODS

Data were collected from registered files at the department of gynecology and obstetrics in Tanta University Hospital from January 2004 to December 2008. Data included personal history (age, residence), medical history, obstetric history (antenatal care, number of pregnancies, number of labor) operative details and suspected cause of death. In situations where these data were deficient, verbal autopsy was done through interview with patient relatives or phoning them.

Statistical Analysis

Data were expressed as number and percentage and Chi-square was used to determine the level of significance .

RESULTS

From January 2004 till December 2008, a total of 187 maternal deaths were recorded during the 5-year study period, out of 19,619 cases admitted at the Department of Obstetrics at our university hospital, giving a maternal mortality ratio (MMR) of 953/100,000 deliveries. The yearly MMR was 950/100,000 in 2004, 925/100,000 in 2005, 947/100,000 in 2006, 953/100,000 in 2007 and 677/100,000 in 2008.

Personal History

Age: Age ranged from 18 to 43 years. The mean age was 34.9±6.44 years, 121 cases (64.7%) were above 35 years.

Residence: 110 patients came from rural area and 77 patients from urban areas (P=0.048) [Table 1].

Table 1

Distribution of cases according to residence

Site of Medical Care

More than one-third of the cases (35%) were referred from outside hospital (private clinics, private hospitals, maternity care units, general hospitals) [Table 2].

Table 2

Distribution of cases according to the site of delivery

Obstetric History

Exactly 133 cases were multiparous (71%) while 54 cases were primigravida (29%) (P=0.0005).

Concerning antenatal care, majority of the cases received no antenatal care (65%); only 10 cases had regular antenatal care (5.3%). Rest of the cases experienced irregular antenatal care (29.7%) [Table 3].

Table 3

Distribution of cases according to antenatal care

Concommittent Disease

Twenty-two cases (12%) involved in this study had past history of hepatic, cardiac, or other chronic diseases.

Method of Delivery

Exactly 120 cases in this study delivered by cesarean sections (64.2%) and only 35 cases have had vaginal delivery (18. 7%) (P=0.00002) [Table 4].

Table 4

Distribution of cases according to the type of labor

Time of Death

Eighty-eight cases in this study died after delivery, representing 47% of total cases; 67 cases (36%) died during labor and only 17% died before labor [Table 5].

Table 5

Distribution of cases according to time of death

Cause of Death

The first leading cause of obstetric death was postpartum hemorrhage (18.2%) followed by eclampsia (17.1%), pre-eclampsia (11.2%) and postpartum eclampsia (10.7%). Ruptured uterus led to death in 10.2% of the cases and accidental hemorrhage in 8.6% of cases. Amniotic fluid embolism was suggested as a cause of death in 9.1% of the cases and anesthesia in 8% of the cases. In 6.9% of the cases, the cause of death was unexplained [Table 6, Figure 1].

Table 6

Distribution of cases according to the cause of death

Figure 1

Pie chart showing percentage incidence of mortality

Regarding maternal deaths related to direct anesthetic causes, 15 women died in this study. eleven women were under general anesthesia and only four were under spinal (epidural or intrathecal) anesthesia; 10 women were morbidly obese.

Causes of anesthetic maternal mortality:

Four deaths were due to difficult airway management with trainee.

Two deaths were due to high spinal block.

Two deaths were due to inadvertent intrathecal adminstration during epidural block.

One death was due to aspiration during anesthetic emergency.

Two deaths were attributed to lack of preoperative evaluation (emergency) and unknown preoperative medical conditions (cardiomyopathy and ischemic heart disease).

One death was attributed to lack of monitoring and failure to detect postoperative apnea in postoperative care unit.

Two deaths were due to overdose of opioid at the end of operation in morbidly obese patients and failure to detect because of absence of pulse oximetry in postoperative care unit.

One death was due to barotruma and tension pneumothorax in morbidly obese patients.

DISCUSSION

Maternal mortality rate recorded in this study (953 per 100,000) is higher than the mortality rate in Egypt (84 per 100,000). This may be explained based on the fact that Tanta university hospital is a tertiary care unit and complicated cases from peripheral areas are referred to the hospital.

In the current study, anesthesia was responsible for about 8% of the causes of death and a large proportion of the cases (59%) came from rural areas. This may play a role in increased maternal mortality. However, in a recent South African maternal mortality report, anesthesia was the cause of 5% of direct maternal deaths.[5] Another study in the sub-Saharan African country of Zimbabwe put the avoidable maternal mortality rate in their hospital at 21/10,000 cesarean deliveries/anesthetics.[6]

The incidence of failed intubation in obstetric patients (1:280) is higher than that in the general operating theater (1:2230).[78] This is explained by difficult airway caused by enlarged tongue, breasts, vascular engorgement and edema of nasal, oral pharynx, larynx and trachea. Failed intubation and aspiration were responsible for five deaths in our study. Reducing the incidence of aspiration or failed intubation by either avoiding general anesthesia or standardizing airway management became the focus of attention. Maternal mortality rate was significantly declined by improving monitoring techniques during general anesthesia,[2] such as pulse oximetry (1989), the introduction of the ASA Difficult Airway Algorithm (1993), and capnography (1995); so, it must be available in all operating theaters.

Pre-anesthetic visits for evaluation of suspected difficult airway and premedication with antacids and H2 receptor antagonists is a must for improving general anesthesia outcome.[9]

There have been reports of anesthesia-related maternal mortality with regional anesthesia performed by poorly trained providers of anesthesia.[1011] Regional anesthesia was responsible for about four deaths in our study; so, provision of safe regional anesthesia is mandatory to decrease mortality related to anesthesia.

Interestingly, in this study, more than one-third of obstetric deaths (35%) were referred from outside hospital. This may be due to delay in receiving adequate health care at the facility or delay in referral which put a great burden on anesthesiologist for this emergency difficult situation.

We found that 64.7% of the cases were above 35 years, 71% of the cases were multiparous and majority of the cases received no antenatal care (65%). Girls below 18 years and women above 34 years have been reported to be at a higher risk of pregnancy-related mortality.[12] Multiparous women, multiple pregnancies and the women who have undergone IVF have also been reported to be at a higher risk of maternal deaths. Ethnicity has also been associated with maternal deaths and so is the social class and access to health care.[12]

This study revealed that 64.2% of mortality cases were undergoing cesarean section. Many studies have found that the risk for maternal death is significantly greater for women undergoing cesarean section than for those who have a vaginal delivery.[13] The increased risk of cesarean delivery may be related not only to the labor or delivery complications necessitating the cesarean section but also to the specific risks of anesthesia for this method of delivery. Eighty-eight cases in this study died after delivery. This may highlight the importance of postoperative intensive care ready to deal with cases of bleeding and other emergencies.

Recommendations of our study include: increased utilization of regional anesthesia for both vaginal and operative delivery regarding availability of resuscitation drugs and equipment; early epidural placement in patients at highest risk for urgent cesarean delivery; use of algorithms for difficult intubation with adaptations for fetal distress; equipment and resuscitation drugs should be available in obstetric theater; elective fiberoptic intubation in patients with anticipated difficult intubation, which is not easily available due to shortage of financial resources in a developing country; consultant should be available all the times and avoid inappropriate delegation of responsibility (telephone consultation); improvement of intensive care facility, blood products and a clear policy for the prevention or treatment of conditions such as pulmonary embolism, eclampsia or massive hemorrhage.