Cephalic Spread of Block With Head Down Tilt in Spinal Anaesthesia - A Randomised Controlled Study

Not Applicable

Completed

• Conditions: Head-Down Tilt Following Spinal Anesthesia
• Interventions: Procedure: Group C - neutral; Procedure: Group Y - head low tilt; Procedure: Group X - head low tilt

• Registration Number: NCT03491319
• Lead Sponsor: Nitte University

Brief Summary

Subarachnoid block has become an established and reliable method of providing anaesthesia for lower abdominal and lower limb surgeries. Several factors determine the spread of local anaesthetic solutions in CSF. Among them, patient position is an important determining factor. Anesthesiologists give various degrees of head down tilt which they believe is both safe for the patient and will result in adequate level of block. Often these are arbitrarily done by the operator as most of the operation theatre tables are not equipped with any device to measure the accurate degree of tilt. As there is no agreement on the effect of Trendelenberg position on height of subarachnoid block, the current clinical study will be undertaken to estimate the effect of operation theatre table tilt at the time of lumbar puncture on the height of subarachnoid block.

Detailed Description

Subarachnoid block has become an established and reliable method of providing anaesthesia for lower abdominal and lower limb surgeries. A definitive advantage that subarachnoid block provides is the profound nerve block that can be produced in a large part of the body by the relatively simple injection of a small amount of local anaesthetic. Twenty-five factors have been invoked as determinants of the spread of local anaesthetic solutions in CSF. Among them, patient position is an important determining factor.

Operation theatre table tilts have been used to influence the spread of hyperbaric solution to ultimately influence the final height of the block. Studies have shown that a 10 degree head down tilt can result in cephalad spread of analgesia when compared to the horizontal group. So, in cases where the spinal block level was not high enough to perform a given surgery, the Trendelenburg position has been used to extend the level of the block. Hence, it is assumed that a higher level of block can be achieved with a smaller volume of the local anaesthetic agent, thus reducing the side effects. But others have noted that there was no statistically significant increase in the level of block even with 15 degree head down tilt.

In spite of this, anesthesiologists give various degrees of head down tilt which they believe is both safe for the patient and will result in adequate level of block. Often these are arbitrarily done by the operator as most of the operation theatre tables are not equipped with any device to measure the accurate degree of tilt.

An application called clinometer that utilizes the gyroscope sensor and determines the plane of the gadget in vertical as well as horizontal directions has been described. This application can be used to measure the exact degree of tilt given after sub arachnoid block.

As there is no agreement on the effect of Trendelenberg position on height of subarachnoid block, the current clinical study will be undertaken to estimate the effect of operation theatre table tilt at the time of lumbar puncture on the height of subarachnoid block.

Study Timeline

• Study Start: 2016-10-01
• Primary Completion: 2017-01-31
• Study Completion: 2017-01-31
• Status Verified: 2017-07
• Study First Submitted: 2018-03-31
• Study First Submitted QC: 2018-03-31
• Last Update Submitted: 2018-03-31
• Study First Posted: 2018-04-09
• Last Update Posted: 2018-04-09

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 60

Inclusion Criteria

• Patients belonging to ASA physical status I and II undergoing lower abdominal and lower limb surgeries under spinal anaesthesia

Exclusion Criteria

• Patient refusal
• contraindicated for spinal anaesthesia
• allergy to local anaesthetic agents used
• obesity (body mass index >29 kg/m2)
• Pregnancy

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Group C Control	Group C - neutral	spinal anaesthesia was given with table in neutral positon. Same position was maintained after spinal anaesthesia
Group Y	Group Y - head low tilt	the table was put in 10 degree head low position before proceeding to give spinal anaesthesia. Head low position was maintained for 10 minutes following spinal
Group X	Group X - head low tilt	spinal anaesthesia was given with table in neutral positon. 10 degree head low position was maintained for 10 minutes following spinal

Primary Outcome Measures

Name	Time	Method
Maximum height of block	from 5 minutes to 150 minutes after intrathecal injection
Two segment regression time	from 5 minutes to 150 minutes after intrathecal injection	time from injection of spinal drug to regression of the sensory block by two segments from the maximum

Secondary Outcome Measures

Name	Time	Method
Hypotension	every minute for 5 min after intrathecal drug administration, every 5 min till 30 min and thereafter every 10 minutes till 150 minutes after intrathecal injection	drop in systolic blood pressure to less than 30% of baseline values or systolic blood pressure (SBP) below 90mmHg
Bradycardia	every minute for 5 min after intrathecal drug administration, every 5 min till 30 min and thereafter every 10 minutes till 150 minutes after intrathecal injection	heart rate less than 50bpm or decrease by more than 30% below baseline value.
Tachycardia	every minute for 5 min after intrathecal drug administration, every 5 min till 30 min and thereafter every 10 minutes till 150 minutes after intrathecal injection.	heart rate more than 100bpm or increase by more than 30% over baseline value.