Hypertensive disorders in pregnancy include preeclampsia, eclampsia, and HELLP syndrome (Hemolysis, Elevated Liver enzymes, and Low Platelet count), each of which presents distinct challenges for anesthesia management. To safely administer anesthetic care to these patients, anesthesia providers must fully grasp the underlying pathophysiology of these conditions and their potential impact on anesthetic planning and intervention.
Preeclampsia
Preeclampsia is a multisystem disorder that typically develops after 20 weeks of gestation and is characterized by new-onset hypertension and proteinuria. In some cases, it may also present without proteinuria but with other end-organ damage, such as renal dysfunction, hepatic involvement, or neurological symptoms. While the precise cause of preeclampsia is not fully understood, abnormal placentation is thought to be a key initiating factor, leading to endothelial dysfunction, vasospasm, and increased vascular permeability.
From an anesthetic perspective, the endothelial dysfunction and increased vascular permeability present significant challenges. Intravascular volume may be depleted, despite edema, complicating fluid management. Blood pressure control becomes critical to avoid further end-organ damage. Anesthesia providers must be acutely aware of the risk of exacerbating hypertension with intubation or other stimuli. General anesthesia in patients with preeclampsia can result in significant hypertension during induction, so strategies for smooth induction and maintenance are crucial. Regional anesthesia, such as epidural or spinal anesthesia, is often preferred in preeclampsia cases, as it helps to manage blood pressure more effectively and avoids the hypertensive spikes associated with general anesthesia.
Eclampsia
Eclampsia refers to the development of seizures in a patient with preeclampsia. It remains a life-threatening emergency, as seizures can lead to severe hypoxia, placental abruption, or aspiration. In the context of anesthesia, the management of eclamptic seizures includes airway protection, control of the seizure, and stabilization of maternal and fetal hemodynamics.
Magnesium sulfate is the mainstay of therapy for seizure prevention and treatment in preeclamptic and eclamptic patients. Anesthesia providers must be familiar with the dosing and side effects of magnesium sulfate, which include respiratory depression and muscle weakness. Careful monitoring of neuromuscular function is essential, particularly if general anesthesia is required, as magnesium potentiates neuromuscular blockade. In cases where regional anesthesia is feasible, it is often preferred due to its beneficial effects on blood pressure and the avoidance of the systemic effects of general anesthesia.
HELLP Syndrome
HELLP syndrome is a severe variant of preeclampsia, characterized by hemolysis, elevated liver enzymes, and low platelet counts. It can rapidly deteriorate, leading to liver rupture, disseminated intravascular coagulation (DIC), and multi-organ failure. For anesthesia providers, the low platelet count associated with HELLP syndrome is particularly concerning, as it increases the risk of bleeding during surgical and anesthetic procedures.
In patients with HELLP syndrome, decisions regarding the use of regional anesthesia must be made carefully. If the platelet count is severely low (<100,000/microliter, though some providers use <70,000/microliter as a threshold), regional anesthesia may be contraindicated due to the risk of epidural hematoma. General anesthesia may be required in such cases, though it also comes with significant risks. Meticulous hemodynamic management and monitoring of coagulation parameters are critical throughout the perioperative period.
| Feature | Preeclampsia | Eclampsia | HELLP syndrome |
|---|---|---|---|
| Defining picture | Multisystem disorder after 20 weeks with new-onset hypertension and proteinuria, or without proteinuria but with renal, hepatic, or neurological end-organ damage. | Seizures developing in a patient with preeclampsia. | Hemolysis, elevated liver enzymes, and low platelet count. |
| What makes it dangerous | Abnormal placentation is thought to initiate endothelial dysfunction, vasospasm, and increased vascular permeability. | Seizure activity threatening severe hypoxia, placental abruption, or aspiration. | Rapid deterioration toward liver rupture, disseminated intravascular coagulation, and multi-organ failure. |
| Chief anesthetic concern | Intravascular volume may be depleted despite edema, complicating fluid management; intubation and other stimuli can worsen hypertension. | Airway protection and seizure control while maternal and fetal hemodynamics are stabilized. | Low platelet count raises bleeding risk during surgical and anesthetic procedures. |
| Technique preference | Regional anesthesia is often preferred; it controls blood pressure better and avoids the hypertensive spikes of general anesthesia. | Regional preferred where feasible, for its blood pressure effects and avoidance of systemic general anesthetic effects. | Regional may be contraindicated at a severely low platelet count — <100,000/µL, with some providers using <70,000/µL — because of epidural hematoma risk. |
| Management priority | Blood pressure control to prevent further end-organ damage. | Magnesium sulfate is the mainstay for seizure prevention and treatment; it causes respiratory depression and weakness and potentiates neuromuscular blockade. | Meticulous hemodynamic management with monitoring of coagulation parameters throughout. |
