DOI: https://doi.org/10.21203/rs.3.rs-2172034/v1
The incidence of cerebral aneurysms in the pregnant population is similar to that of the non-pregnant population. Subarachnoid hemorrhage occurs in 5.8 per 100,000 deliveries among women between 15- and 44-year-old. Studies have found that the incidence of aneurysmal rupture is higher during the third trimester and lower during the first trimester. The risk of aneurysmal rupture and subarachnoid hemorrhage during general anesthesia or spinal anesthesia is unclear. We report a case of aneurysm rupture in the postpartum period.
We describe a case of a 28-year-old woman, Gravida 3 Para 2, who went elective Cesarean delivery under spinal anesthesia at 39 weeks. She developed a headache, right-sided body weakness, and left-sided focal seizures postoperatively. Computed Tomography (CT) scan showed basal ganglia hemorrhage with intraventricular extension, subarachnoid hemorrhage, and midline shift to the right side. The World Federation of Neurological Surgeons (WFNS) grade was 4, and the modified Fischer grade was 4. A right frontal external ventricular drain was inserted, and the patient was admitted to the intensive care unit (ICU). Magnetic Resonance Angiography (MRA) and Magnetic Resonance Venography (MRV) showed a small left supraclinoid aneurysm, and the patient underwent balloon-assisted coiling. Seven days later, the Glasgow Coma Scale (GCS) dropped again, the Computed Tomography (CT) scan showed brain edema, and decompressive craniectomy was done. The patient subsequently improved, and later the external ventricular drain (EVD) was removed, and the patient was referred to a rehabilitation center. Cranioplasty was done three months later. Glasgow Outcome Scale (GOS-E) after six months was 6 (moderate disability).
The use of vasopressors and cerebrospinal fluid (CSF) leakage may increase the risk of cerebral aneurysm rupture after spinal anesthesia.
Globally, the incidence of subarachnoid hemorrhage was estimated to be 6.1 per 100,000 person-years in 2010.1 The incidence of cerebral aneurysms in the pregnant population is similar to that of the non-pregnant population. In a nationwide study in the United States, the prevalence of pregnancy-related SAH was 5.8 per 100,000 deliveries among women between 15 and 44-year-old. Two third of these cases were postpartum. It has also been suggested that the SAH in pregnant patients is less likely to be aneurysmal compared to the general population.2
An Egyptian 28-year-old woman, Gravida 3 Para 2, unknown to have any chronic illness, was admitted to the hospital at 39 weeks for elective Cesarean delivery under spinal anesthesia. She had a history of two previous Low Segment Caesarean Section (LSCS) with no complications.
Preoperatively, the blood pressure was 145/80 mmHg, and the heart rate was 75 beat-per-minute (bpm). The clinical exam was within normal limits, and the preoperative laboratory investigations were within normal limits. The patient received 10mg of Heavy Bupivacaine intrathecally. The heart rate dropped subsequently to 49 bpm, ephedrine 6 mg was administered, and the heart rate was improved to 60 bpm. Additionally, the patient received Lactated Ringer solution of 1500 mL. Urine output was 600 mL during the surgery, and the estimated blood loss was 250 mL. She also received Cefazoline, Oxytocin, Ranitidine, Diclofenac, Dexamethasone, and Paracetamol. The surgery went smoothly, and a baby girl was born.
Postoperatively, the patient was transferred to the recovery room. In the recovery room, the blood pressure ranged between 140–150/70–80 mmHg, and the heart rate was around 60 bpm. One hour later, the patient developed a headache without any neurological deficit. Four hours after the procedure, the patient developed right-sided weakness and left-sided focal seizures. Her Glasgow Coma Scale (GCS) was 13 (Eye-opening 4, Motor 5, and Verbal 4). Power was 0 in both the right upper and lower limbs. Pupils were equal and reactive. Blood pressure was 140/80, Heart Rate was 70, SpO2 was 95% on room air, and the respiratory rate was 20 bpm. The patient received IV phenytoin. An emergency Computed Tomography (CT) head scan was done, and the patient was transferred to the Intensive Care Unit (ICU). The CT scan showed a left basal ganglia hemorrhage of 50x37x37 mm, with a mass effect over the left lateral ventricle and a midline shift of 4mm to the right side, with intraventricular extension to the lateral, third, and fourth ventricles [see Fig. 1]. There was also a subarachnoid hemorrhage with blood in the basal cisterns and the suprasellar and Sylvian fissures. The World Federation of Neurological Surgeons (WFNS) grade was 4, and modified Fischer grade 4.
The Glasgow Coma Scale (GCS) did drop further to 7 (Eye-opening 4, Motor 5, Verbal 1), and the patient was subsequently intubated. The patient was then taken to the operating theatre, and a right frontal external ventricular drain (EVD) was inserted. Further evaluation by magnetic resonance angiography (MRA) and venography (MRV) showed a small left supraclinoid aneurysm measuring 4X4 mm. The patient underwent balloon-assisted coiling. The patient was extubated three days later.
Seven days after the initial incident, the patient became drowsy, and Glasgow Coma Scale (GCS) dropped again to 8. Computed Tomography (CT) scan showed brain edema, and she was taken again to the operating theatre and underwent decompressive craniectomy. The patient did improve afterward. She was extubated, the intracranial pressure (ICP) monitor was weaned off, and the external ventricular drain (EVD) was removed. Her Glasgow Coma Scale (GCS) became 15, with right upper limb power of 0/5, right lower limb power of 3/5, and right upper motor neuron facial nerve palsy (grade 3). A follow-up Computed Tomography (CT) angiogram showed 10% filling in the aneurysm.
She had been transferred to the rehabilitation center. Cranioplasty was done three months later. At six months, her right upper limb power was 1/5, and her right lower limb power was 4/5. Glasgow Outcome Scale (GOS-E) at six months was 6 (moderate disability).
Although subarachnoid hemorrhage is rare during frequency, the maternal mortality rate can vary from 13–35%, and the fetal mortality rate can range from 7–25%.3 A review of 167 patients found that the incidence of subarachnoid hemorrhage (SAH) during pregnancy was lower in the first trimester (< 15 weeks) and higher in the third trimester (30–40 weeks).4 A recent retrospective study of pregnant women with SAH found that pregnancy and labor do not increase the rate of aneurysmal rupture.5
The risk of aneurysmal rupture during anesthesia is unclear. A retrospective study of patients who underwent non-aneurysm-related surgical procedures found that general anesthesia didn’t precipitate aneurysm rupture during or within one week of the surgery.6 However, the sample size of this study and the possibility of selection bias limit its usefulness, and larger prospective studies are needed to evaluate the association further. There are no studies found in the literature that investigated the relationship between neuraxial anesthesia and SAH. However, some cases have been reported.7–10
The transmural aneurysmal pressure gradient (TMPG) is the pressure difference between the mean arterial pressure (the aneurysmal intraluminal pressure) and the intracranial pressure (the extraluminal pressure).11 It has been postulated that the cerebrospinal fluid (CSF) leak may decrease intracranial pressure, subsequently increasing the aneurysmal transmural pressure gradient (TMPG), causing rupture of the aneurysm.7,10 It is also possible that vasopressors (e.g., Ephedrine) might cause an increase in the mean arterial pressure (MAP), leading to rupture of the aneurysm.8 Ephedrine was used in the case described above.
Possible strategies to reduce the risk of aneurysmal rupture during anesthesia include blood pressure monitoring and control, avoiding spikes of systolic blood pressure over 140–150 mmHg, preventing vomiting, and minimizing coughing.6
The management of peripartum aneurysmal subarachnoid hemorrhage should be the same for non-pregnant patients. Coiling or clipping should be performed immediately to avoid rebleeding.12 The literature, however, lacks studies that compare coiling and clipping outcomes during pregnancy and postpartum.
This case suggests that cerebral aneurysm may rupture in the perioperative period. The use of vasopressors and cerebrospinal fluid (CSF) leakage increases the risk of cerebral aneurysm rupture after spinal anesthesia.
bpm: beat per minute
CSF: Cerebrospinal Fluid
CT: Computed Tomography
EVD: External Ventricular Drain
GCS: Glasgow Coma Scale
GOS-E: The Glasgow Outcome Scale Extended
ICP: Intracranial Pressure
ICU: Intensive Care Unit
LSCS: Lower Segment Cesarean Section
MAP: Mean Arterial Pressure
MRA: Magnetic Resonance Angiography
MRV: Magnetic Resonance Venography
SAH: Subarachnoid Hemorrhage
TMPG: Transmural Aneurysmal Pressure Gradient
WFNS: World Federation of Neurological Surgeons
Ethical declarations:
Informed consent is obtained from the patient to publish the case. IRB review is not required for case
Competing interests:
No competing interests to declare
Funding:
None to disclose
Acknowledgements:
None to disclose
Authors Contributions:
AS performed the literature review and drafted the manuscript. NS provided critical revision of the manuscript for intellectual content and provided input on the concept and design of this paper. The authors read and approved the final manuscript.