A randomized controlled study to compare the accuracy of pre-procedural ultrasound versus conventional landmark method for locating subarachnoid space in patients undergoing cesarean delivery under spinal anaesthesia

Spinal anaesthesia is gold standard anaesthetic technique in obstetric patients because of lower complication rate and better neonatal outcome as compared to general anesthesia

However in obstetric patients there are increased lumbar lordsis, obesity and soft tissue edema making spinal anesthesia technically more challenging ,also there are many more anatomical and physiological changes in pregnancy predisposing them to multiple needle pass attempts and  increased difficulty in administrating successful subarachnoid block.

Use of landmark method of locating subarachnoid space may sometime be inaccurate, which invariably leads to repeated attempts and redirections of the needle leading to complications such as bloody tap, nerve injury, spinal hematoma, paresthesia, postdural puncture headache, patient discomfort and dissatisfaction and delay in treatment which may sometimes also affect the neonatal outcome.

Due to challenges associated with spinal anaesthesia in obstetric patients, pre-procedural ultrasound could be helpful in locating the subarachnoid space accurately thus decreasing the number of attempts and needle redirections while performing the subarachnoid block, reducing many complications.

The existing literature explores the utility of pre-procedural ultrasound in various patient populations, but its application in obstetric anesthesia remains relatively underexplored. Therefore we planned our study in obstetric population which may guide about its utility routine practice.

Administrating spinal anaesthesia is difficult in obstetric patients due to various anatomical and physiological changes. This causes multiple needle pass attempts leading to many complications such as bloody tap, nerve injury, spinal hematoma, paresthesia, post dural puncture headache, patient discomfort and dissatisfaction.

Pre-procedural ultrasound may facilitate spinal anaesthesia by locating the accurate needle insertion point accurately in obstetric patients making the technique easier resulting in lesser needle first pass attempts, ultimately enhancing maternal and neonatal outcomes.

There is a paucity of literature regarding utility of pre-procedural ultrasound for locating sub arachnoid space in obstetric patients, its superiority over the landmark technique has not been proven yet.