Role of Intravenous Dexmedetomidine in Reducing Shivering After Shivering Cesarean Section Due to Spinal Anesthesia

Post-spinal shivering is a common complication that occurs in 40-65% of patients undergoing spinal anesthesia. It is characterized by involuntary, rhythmic muscle contractions that can lead to discomfort, anxiety, and increased oxygen consumption.

The exact mechanisms underlying post-spinal shivering are not fully understood, but several factors contribute to its development:

• *Hypothermia*: Spinal anesthesia can cause a decrease in core body temperature, leading to shivering.
• *Sympathetic blockade*: Spinal anesthesia blocks sympathetic nerve fibers, causing vasodilation and decreased blood flow to the extremities.
• *Increased oxygen consumption*: Shivering increases oxygen consumption, which can be detrimental in patients with pre-existing cardiovascular or respiratory disease.

*Effects of Dexmedetomidine on Post-Spinal Shivering*

Dexmedetomidine, an alpha-2 adrenergic agonist, has been shown to effectively reduce post-spinal shivering. Its effects include:

• *Decreased shivering intensity*: Dexmedetomidine reduces the severity of shivering, making patients more comfortable.
• *Increased core body temperature*: Dexmedetomidine helps to maintain core body temperature, reducing the likelihood of hypothermia-induced shivering.
• *Reduced oxygen consumption*: By decreasing shivering, dexmedetomidine reduces oxygen consumption, which is beneficial for patients with cardiovascular or respiratory disease.
• *Improved patient comfort*: Dexmedetomidine's sedative and anxiolytic effects contribute to improved patient comfort and satisfaction.
• *Reduced need for other anti-shivering interventions*: Dexmedetomidine's effectiveness in reducing post-spinal shivering may reduce the need for other interventions, such as meperidine, clonidine, or forced-air warming.

Dexmedetomidine's anti-shivering effects are thought to be mediated by its actions on the following mechanisms:

• *Alpha-2 adrenergic receptors*: Dexmedetomidine activates alpha-2 adrenergic receptors, which decreases sympathetic outflow and reduces shivering.
• *Hypothalamic thermoregulation*: Dexmedetomidine may affect the hypothalamus, the body's thermoregulatory center, to reduce shivering and maintain core body temperature.
• *Spinal cord mechanisms*: Dexmedetomidine may also act on the spinal cord to reduce shivering, possibly by inhibiting the release of excitatory neurotransmitters.

Inclusion criteria

• Elective Cesarean section
• Age limit 18 to 35 years
• ASA II

Exclusion criteria

• Emergency cesarean delivery
• hypersensitive to dexmedetomidine
• Pateint with hear, renal, or hepatic diseases requiring follow up
• Pre-eclemptic pateint
• Patient with GA
• Combined spinal epidural anesthesia