Hemodynamic Instability
Significant fluctuations in blood pressure, heart rate, or cardiac output during obstetric procedures. Common with neuraxial anesthesia and requires prompt intervention to maintain uteroplacental perfusion.
Full Definition
Hemodynamic instability in obstetric anesthesia refers to significant, often rapid changes in cardiovascular parameters including blood pressure, heart rate, cardiac output, and systemic vascular resistance. This is particularly common following neuraxial blockade due to sympathetic nervous system blockade, which can cause profound hypotension, bradycardia, and decreased venous return. In pregnant patients, hemodynamic instability poses risks to both mother and fetus by compromising uteroplacental blood flow and oxygen delivery. Risk factors include high sensory block levels, inadequate preloading, aortocaval compression, and pre-existing cardiovascular disease. Management involves immediate recognition, left uterine displacement, intravenous fluids, and vasopressors such as phenylephrine or ephedrine. Severe cases may require advanced cardiovascular support.
Usage
Usage note: Use specific terms when possible (e.g., 'hypotension,' 'bradycardia') rather than the general term 'hemodynamic instability.'
In Context
- "Hemodynamic instability following the spinal block required immediate vasopressor support and fluid resuscitation." — Case report
- "Continuous hemodynamic monitoring is essential during cesarean section to detect and treat instability promptly." — Clinical protocol