What is the mortality rate associated with general anesthesia in pregnant patients over the past five years?

Mortality with General Anesthesia in Pregnant Patients: Recent Evidence

Current Mortality Rates and Trends

General anesthesia for cesarean delivery continues to carry significantly higher maternal mortality risk compared to neuraxial techniques, with a three-fold increased odds of maternal death in low-to-middle income countries and a 16.7-fold increased case-fatality risk ratio in the United States after 1985. 1, 2

Quantified Mortality Data

• Anesthesia-related maternal mortality accounts for 2.8% of all maternal deaths globally, 3.5% of direct maternal deaths, and 13.8% of deaths after cesarean section 1
• The overall risk of death from anesthesia in women undergoing obstetric procedures is 1.2 per 1,000 women (95% CI 0.8-1.7) in low-to-middle income countries 1
• In the United States, anesthesia-related maternal mortality decreased from 4.3 per million live births (1979-1981) to 1.7 per million (1988-1990), though deaths involving general anesthesia have remained stable in absolute numbers 2

Critical Risk Comparison: General vs. Neuraxial Anesthesia

The evidence unequivocally demonstrates that general anesthesia triples the odds of maternal death compared to neuraxial anesthesia, with this disparity increasing over time. 3, 1

• General anesthesia increases odds of maternal death by 3.3-fold (OR 3.3,95% CI 1.2-9.0) compared to neuraxial anesthesia 1
• The case-fatality risk ratio for general anesthesia was 2.3 times that of regional anesthesia before 1985, but increased to 16.7 times (95% CI 12.9-21.8) after 1985 2
• Perinatal deaths are also increased 2.3-fold with general anesthesia (OR 2.3,95% CI 1.2-4.1) 1

Primary Mechanisms of Mortality with General Anesthesia

Airway-Related Complications (Leading Cause)

Failed intubation and airway management complications remain the primary cause of anesthesia-related maternal mortality with general anesthesia. 4, 3, 5

• Pregnancy causes airway edema, friability, hypersecretion, and smaller upper airway diameter, making intubation significantly more difficult than in non-pregnant patients 5
• Rapid desaturation occurs during apnea due to decreased functional residual capacity and increased oxygen consumption 5
• Hypoxemia from difficult airway management is a specific documented risk of general anesthesia mortality 4, 3

Pulmonary Aspiration

• Pulmonary aspiration risk is substantially elevated in pregnant patients, particularly those in labor or with a full stomach 4, 3
• The risk profile increases significantly when the patient is not adequately starved, is in labor, or has not received antacids 4

Thromboembolic Complications

• Thromboembolic complications contribute to general anesthesia mortality risk in the obstetric population 4, 3

Specific High-Risk Clinical Scenarios

When General Anesthesia Mortality Risk is Highest

The following situations carry the greatest mortality risk with general anesthesia 4:

• Patient in active labor (full stomach)
• Emergency cesarean section without adequate preparation time
• Lack of antacid prophylaxis
• Anticipated difficult airway without awake intubation planning
• Rural or low-resource settings with non-physician anesthetists

Provider-Related Mortality Factors

The rate of maternal death is nearly double when managed by non-physician anesthetists (9.8 per 1,000 anesthetics) compared to physician anesthetists (5.2 per 1,000). 1

Evidence-Based Recommendations to Minimize Mortality

Primary Prevention Strategy

Neuraxial anesthesia (spinal or epidural) should be used for cesarean delivery whenever clinically feasible, as it is associated with significantly lower maternal mortality and morbidity rates. 3, 5

• The American Society of Anesthesiologists recommends neuraxial techniques over general anesthesia for most cesarean deliveries 3
• Regional anesthesia is the first-line approach and should be used even in many urgent circumstances 6

Limited Indications for General Anesthesia

General anesthesia should be reserved only for specific emergency circumstances where neuraxial techniques are contraindicated or time does not permit their use. 3

Appropriate indications include 3:

• Profound fetal bradycardia requiring immediate delivery
• Ruptured uterus
• Severe hemorrhage with hemodynamic instability
• Severe placental abruption
• Umbilical cord prolapse
• Preterm footling breech (in specific circumstances)

Critical Safety Measures When General Anesthesia is Required

If general anesthesia is necessary, awake tracheal intubation should be used rather than rapid sequence induction when significant airway difficulties are predicted. 5

• Multidisciplinary planning with antenatal assessment is essential for patients with anticipated difficult airways 4, 5
• Equipment, facilities, and support personnel must be comparable to the main operating suite 3
• Never underestimate airway difficulty in pregnant patients 5

Recent Trends and Persistent Concerns (Last 5 Years)

Evolving Mortality Patterns

• While the absolute number of general anesthesia-related deaths has remained stable, they now account for an increased proportion of total anesthesia-related maternal deaths because regional anesthesia deaths have decreased 2, 7
• Fatal complications during obstetric regional anesthesia have doubled in recent years, though general anesthesia fatality risk remains substantially higher 7
• Many reported maternal deaths are potentially avoidable with adherence to current guidelines and standards 7

Persistent Disparities

Racial and socioeconomic disparities and low-resource settings are major contributing factors in both the use of general anesthesia and associated maternal mortality. 6

• Both maternal and perinatal mortality increase when general anesthesia is provided in low-resource settings 6
• Unnecessary general anesthesia for cesarean delivery is associated with serious anesthesia-related complications, surgical site infection, and venous thromboembolic events 6

Critical Pitfalls to Avoid

• Never choose general anesthesia for convenience or speed in non-emergency situations 3
• Do not delay spinal anesthesia to administer a fixed volume of IV fluid 3
• Avoid underestimating airway difficulty in pregnant patients—use awake intubation techniques when significant difficulties are predicted 5
• Do not fail to provide adequate antacid prophylaxis and ensure appropriate fasting when possible 4
• Ensure early anesthesia consultation and multidisciplinary planning for high-risk pregnancies to avoid delays 5

Quality of Life and Morbidity Considerations

Beyond mortality, general anesthesia is associated with 6:

• More significant maternal pain postoperatively
• Higher rates of postpartum depression requiring hospitalization
• Reduced immediate mother-infant bonding
• Lower Apgar scores at 1 and 5 minutes compared to neuraxial techniques 3