Comparison of fractionated dose versus bolus dose of injection Levobupivacaine in Spinal Anaesthesia for patients undergoing lower limb and lower abdominal surgery: A Randomized control trial

INTRODUCTION

•Spinal Anaesthesia is a commonly used anaesthetic technique in patients undergoing lower-limb, lower abdomen, pelvis and perineum surgeries. It is often preferred over general anaesthesia for its properties of providing a dense block, rapid action, its effect on mental status being minimal, decreased blood loss and its protective effect against thrombo-embolic complications.

•Spinal Anaesthesia causes a sympathetic blockade by way of sympathetic denervation resulting in prolonged and occasionally severe hypotension. This occurs because of the rapid sympathetic block extension, impeding adaptation of cardiovascular system, hence causing significant morbidity and mortality.

•Fractionated dose of a Spinal Anaesthetic can also be administered, in which two thirds of the total calculated dose is initially administered; and one third dose after a time-gap of 60 seconds, which in turn achieves adequate motor and sensory blockade.

•The administration of fractionated dosage of the local anaesthetic agent, provides a dense block with greater hemodynamic stability.

•In recent years levobupivacaine, the pure S (−) enantiomer of bupivacaine, has emerged as a safer alternative for regional anaesthesia than its racemic parent. It demonstrated less affinity and strength of depressant effects onto myocardial and central nervous vital centers in pharmacodynamic studies, and a superior pharmacokinetic profile.

•Clinically, levobupivacaine is well tolerated in a variety of regional anesthesia techniques both after bolus administration and continuous postoperative infusion. Reports of toxicity with levobupivacaine are scarce and occasional toxic symptoms are usually reversible with minimal treatment with no fatal outcome. Levobupivacaine has not entirely replaced bupivacaine in clinical practice.

•In anesthesia and analgesia practice, levobupivacaine and bupivacaine produce comparable surgical sensory block with similar adverse side effects, and equal labor pain control with comparable maternal and fetal outcome.

AIMS & OBJECTIVES

AIM - The aim of this study is to compare fractionated dose versus bolus dose injection in spinal anaesthesia for patients undergoing lower abdominal surgeries.

OBJECTIVES

Primary objective: To compare hemodynamic stability and duration of analgesia

Secondary objective: To assess time of onset, level and regression of motor and sensory block

To assess two segment regression time

Requirement of vasopressors if any

STUDY DESIGN - A Randomized Control Trial

SAMPLE SIZE

•Alpha error was taken as 0.03, beta- 0.20,

•k=n2/n1=1

•n1 = (σ12+σ2 2/K) (z1−α/2+z1−β) 2 /Δ2

• Δ = |μ2-μ1| = absolute difference between two means

•σ1, σ2 = variance of mean #1 and #2

•n1 = sample size for group #1

•n2 = sample size for group #2

•α = probability of type I error =2.17 at 97% CI

•β = probability of type II error

•z = critical Z value for a given α or β

•k = ratio of sample size for group #2 to group #1

•n1= 24 subjects in group 1≈ 25 subjects

•n2 = 24 subjects in group 2 ≈ 25 subjects

•Hence the total sample size will be 50

MATERIALS AND METHODS

**Inclusion criteria:**ASA GRADE 1, 2 & 3 patients

Age: 18 years to 70 years

Both Gender

Elective and Emergency Surgeries under Spinal Anaesthesia

**Exclusion criteria:**Patients refusing to participate in the study

History of allergy to study drug

Patients with infection at the site of injection, coagulopathy, increased Intracranial Pressure

Severely altered mental status

Spine deformities or history of laminectomy

Unknown duration of surgery,

Patients converted to general anaesthesia intra-operatively.

METHODOLOGY

Spinal Anaesthesia will be given in sitting position with a 26‑gauge Quincke spinal needle in

L3–L4 or L4–L5 interspace after skin infiltration with 2% Inj Lignocaine.

On noticing free flow and aspiration of Cerebrospinal Fluid, Inj Levobupivacaine 0.5% 3.5ml(17.5mg) along with Inj Buprenorphine 0.3 ml(90mcg) will be injected according to respective groups, B and F (group B

– bolus dose group F – fractionated dose)

Group B patients will receive a single bolus dose of 0.5% Inj Levobupivacaine 3.5ml(17.5mg) along with Inj Buprenorphine 0.3ml(90mcg) over 10 seconds

Group F patients will receive fractionated dose of 0.5% Inj Levobupivacaine 3.5ml(17.5mg) along with Inj Buprenorphine 0.3ml(90mcg), two‑third of the total calculated dose given initially followed by one‑third dose after 60 seconds.

After injection of initial two‑third dose, the syringe will be kept attached to the spinal needle for remaining 60 seconds, after which remaining one‑third dose will be administered. Both the drug will be given at a rate

of 0.2 ml/second.

Patients will be put in supine position (5-10â—¦ Trendelenburg).

The time of onset, level and the regression of sensory and motor block will be assessed.

Assessment of sensory block will be done and confirmed by loss of sensation to pinprick, while modified

Bromage scale will be used to assess motor block.

Surgeon will be allowed for incision when sensory block at T10 level and Bromage scale of 3 will be achieved.

Patients with inadequate sensory blockade and requiring conversion to general anaesthesia are excluded from the study.

The number of hypotensive episodes and the use Inj. Ephedrine/Inj Phenylephrine will be

recorded.

The tests will be performed every 5 min till the achievement of maximum sensory and

motor block (Bromage scale 3) and every 30 min post‑operatively until the sensory and motor

variables are back to normal.

REFERENCES

1. Srivastava N, Ahluwalia P, Jheetay GS, Singh G. Bolus dose versus fractionated dose injection

of hyperbaric bupivacaine in spinal anaesthesia among adult patients undergoing lower limb

surgery: A prospective study. Indian J Clin Anaesth 2020;7(2):238-244

2. Bajwa SJ, Kaur J. Clinical profile of levobupivacaine in regional anesthesia: A systematic

review. J Anaesthesiol Clin Pharmacol. 2013 Oct;29(4):530-9. doi: 10.4103/0970-9185.119172.

PMID: 24249993; PMCID: PMC3819850

3. Goyal A, Singi Y, Mallya P, Bhat G, P S. A Comparison Between Intrathecal Levobupivacaine

and Bupivacaine for Quality and Safety During Infraumbilical Surgeries. Cureus. 2022 Oct

22;14(10):e30590. doi: 10.7759/cureus.30590. PMID: 36426304; PMCID: PMC9681702

4. Derakhshan P, Faiz S H R, Rahimzadeh P, Salehi R, Khaef G. A Comparison of the Effect of

Fractionated and Bolus Dose Injection on Spinal Anesthesia for Lower Limb Surgery: A

Randomized Clinical Trial. Anesth Pain Med. 2020;10(5):e102228.

https://doi.org/10.5812/aapm.102228