A comparative study of incidence of Post spinal Anesthesia Shivering associated With use of Dexmedetomidine and Nalbuphine as an adjuvant to 0.5% hyperbaric bupivacaine in lower abdominal surgeries

In the realm of modern anaesthesia practice, the pursuit of excellence in patient care has been an enduring goal. One of the challenges that anaesthesiologists frequently encounter in their clinical practice is the management of post-spinal anaesthesia shivering, a common side effect that can lead to patient discomfort, compromised surgical conditions, and increased healthcare costs. This vexing issue has prompted researchers and clinicians to explore various pharmacological interventions to effectively alleviate this symptom.

Shivering is a thermoregulatory response which is characterized by rhythmic muscle contractions that generate heat in an attempt to maintain normal body temperature. While shivering can occur in various clinical scenarios, its incidence is particularly high in patients undergoing spinal anaesthesia. Spinal anaesthesia is a widely employed technique for surgical procedures below the umbilicus due to its effectiveness and rapid onset of action. However, in many cases spinal anaesthesia is associated with shivering.

Post-spinal anaesthesia shivering poses several challenges in clinical practice. it may cause patient and hemodynamic instability. It may also interfere with the precision and sterility of the surgical field, complicating the work of the surgical team and potentially prolonging surgical times. Lastly, shivering increases oxygen consumption and carbon dioxide production, which can strain the respiratory and cardiovascular systems, particularly in vulnerable patient populations such as the elderly or those with pre-existing medical conditions.

To address these issues, anaesthesiologists have explored various pharmacological interventions to prevent and manage post-spinal anaesthesia shivering. Two drugs that have gained prominence in recent years for their potential efficacy in this regard are Dexmedetomidine and Nalbuphine.

Dexmedetomidine is a highly selective α2-adrenergic agonist. It has sedative, analgesic, and anxiolytic properties. Its unique pharmacological profile has made it a versatile tool in the hands of anaesthesiologists. Dexmedetomidine acts by inhibiting the release of norepinephrine in the central nervous system, leading to reduced sympathetic outflow and a consequent reduction in shivering thresholds. Moreover, it does not suppress ventilation, making it an attractive option for patients undergoing spinal anaesthesia.

Several studies have investigated the potential of Dexmedetomidine in reducing the incidence and severity of post-spinal anaesthesia shivering. These studies have reported promising results, demonstrating that Dexmedetomidine can effectively decrease the occurrence of shivering while maintaining hemodynamic stability and preserving respiratory function. Furthermore, its sedative and analgesic properties contribute to patient comfort and overall satisfaction.

Nalbuphine is a lipophilic semi-synthetic opioid related to both oxymorphone and naloxone. It possesses an agonist action at the kappa – opioid receptor and antagonist action at the mu- opioid receptor to provide reasonably potent analgesia of visceral nociception. Nalbuphine binds to kappa receptors distributed in the spinal cord and brain to produce analgesia. It is mixed synthetic agonist-antagonist, which attenuates the mu- opioid effects and enhances the kappa-opioid effect.

Numerous studies have investigated the use of Dexmedetomidine and Nalbuphine in preventing and treating post-spinal anaesthesia shivering. Some have reported favourable outcomes, showcasing potential of both this drugs to reduce the incidence and severity of shivering without significant adverse effects on respiratory or hemodynamic parameters.

Additionally, direct comparisons between Dexmedetomidine and Nalbuphine in the context of post-spinal anaesthesia shivering are limited, necessitating a comprehensive study to provide clinicians with evidence-based guidance. While both Dexmedetomidine and show promise Nalbuphine in managing post-spinal anaesthesia shivering individually, the choice between them in clinical practice remains largely empirical. Clinicians lack definitive guidance on which drug to choose and at what dose, given the paucity of head-to-head comparative studies.

This study aims to bridge this knowledge gap by conducting a rigorous comparison of Dexmedetomidine and Nalbuphine in the context of incidences of post-spinal anaesthesia shivering in lower abdominal surgeries. Through this comparative investigation, we seek to address several critical questions.