Efficacy of isobaric intrathecal levobupivacine in laproscopic procedures : Case series

After obtaining approval from the Institutional Ethics Committee, the study will be prospectively registered with the Clinical Trials Registry of India and will be conducted at our tertiary care centre.This single-centre, prospective, interventional study will be conducted on 20  patients undergoing elective laparoscopic surgery, after obtaining written informed consent. Patients who are ASA grade 1 and 2 , Age 18-65 years will be included in the study.

A sample size of 20 will be taken to ensure that the expected number of observations per category throughout our analysis will be well over the minimum data required for reliable chi-squared tests and to increase generalizability of our results.

The pre-anaesthetic check-up will be done, written informed consent will be taken and patients will be counselled about the procedure one day prior to surgery. They will be reassured that their discomfort or anxiety would be managed by the administration of systemic medication or GA if the need arose. Similarly, surgeons will be reassured that they could ask for GA if at any point during the surgery they felt that the anaesthetic technique is posing technical difficulty.

Patients will be kept fasting as per standard guidelines.

After establishing monitoring (electrocardiogram, pulse oximetry, non-invasive blood pressure, respiratory rate and end-tidal carbon dioxide), baseline vitals will be noted and an intravenous line will be secured with a 20 gauge cannula.

Pre-loading will be started at this juncture with Ringer lactate (10 ml/kg in approximately 15 minutes). Premedication with glycopyrrolate 0.2 mg, ondansetron 4 mg, and midazolam1 mg will given systemically.

Under all aseptic precautions, sub arachnoid block will be given by midline approach in one of the intervertebral spaces between L1 to L3 spines, with the patient in a sitting position. If the midline approach posed a difficulty, then paramedian approach will be tried. The spinal will be given very cautiously, with a 25 G Quincke spinal needle, until loss of resistance is felt. Once the flow of clear CSF is established, injection levobupivacaine 0.5%(isobaric), 2ml, along with injection fentanyl 25 µg, (as adjuvant), is injected into the subarachnoid space. The patient is subsequently made to lie supine.

All patients will receive oxygen via Hudson’s mask at the flow rate of 5 l/min. Time of anaesthesia is recorded. Vital parameters are recorded every minute for 15 minutes and every 5 minutes thereafter. Upper and lower levels of sensory block are assessed by pinprick every 1-2 min until minimum block levels between T6 to L1 is achieved.

This is noted as the time of onset. At this point in time, the motor block is evaluated according to the modified Bromage scale. (0-able to lift extended leg, 1- just able to flex knee, 2-no knee movement and some ankle movement, 3- complete lower limb paralysis). Once the onset of block is established surgery will be commenced using carbon dioxide insufflation. The pressure limit of intra-abdominal pressure(IAP) will be kept at 12 mm Hg. Intraoperative adverse events(bradycardia, hypotension etc) will be recorded and managed. Bradycardia (HR<55) will be treated with injection atropine 0.6mg (iv) and hypotension (Systolic BP<80 mm Hg) is managed with 6mg boluses of Injection mephentermine and fast (iv) fluids. Drugs and fluids administered are noted. The intraoperative fluid used will be ringer lactate at the rate of approximately 25ml/min. The rate of infusion can be increased during hypotension. In the end, the duration of surgery is noted.

Patient will be assessed for intraoperative shoulder pain according to visual analog score , and on the score of more than 3 patient is administered with inj fentanyl 100mcg iv .

In the recovery room, vital parameters, sensory and motor block is noted every 15 min until the block regressed completely. Pain scoring will be done as per the Visual Analogue Scale(VAS). Time of onset of postoperative pain (at VAS 3) is recorded. Injection Diclofenac 75 mg will be administered at this point.

Postoperative side–effects in the form of shoulder pain, nausea, vomiting, urinary retention, headache, backache will be noted and managed on day 0, day 1 and day 2. An overall procedure satisfaction score will be established individually for surgeon and patient based on 5 robust scoring criteria to evaluate the success of the procedure.