Analgesic efficacy of dexamethasone as an adjuvant with levobupivacaine in fascia iliaca compartment block undergoing femur neck fracture surgeries: a randomized comparative trial

The study will be conducted in Mahatama Gandhi hospital and Mathura DasMathur Hospital of Dr. S. N. Medical college and associated group of hospitals, Jodhpur. All patients will be examined during preoperative visit, prior to surgery by attending anaesthesiologist. In preoperative visit patient’s detailed history, general physical examination and systemic examination will be carried out. Basic demographic datas like name, age, sex, height, weight will be recorded. A detailed assessment of airway will be performed to rule out any airway difficulty. Routine investigations like hemoglobin (Hb), complete blood count (CBC), renal function test (RFT), urine complete, bleeding time (BT), clotting time (CT), or any specific test (if required) will be carried out. Patients will be explained in detail about the procedure, drugs and visual analogue scale(VAS). All the patients were instructed for minimum 6 hours fasting for solid food and 2 hours for clear liquid.

Continuous ECG, non-invasive blood pressure and peripheral oxyhemoglobin saturation monitor will be applied on arrival to operation theatre prior to block performance. A peripheral intravenous (IV) line will be secured with 18 G cannula on the forearm and 0.5ml/kg/hr crystalloid solution will be started. Patients will be pre-medicated with midazolam 1mg IV. The patients will be randomly allocated to two groups. The block will be performed with ultrasound Machine. The high frequency linear probe will be covered with sterile dressing after applying ultrasound gel. The probe will placed in a horizontal direction over the anterior part of thigh just below the inguinal ligament. Group L will be receiving 30ml of 0.5% levobupivacaine + 2ml normal saline and Group LD will be receiving 30ml of 0.5% levobupivacaine + 2ml dexamethasone.

**Observation:**Standard monitoring will be used throughout the study, including heart rate (HR), SpO2, noninvasive blood pressure (NIBP). Sensory block, VAS will be evaluated every 5 min after block placement to assess the adequacy of surgical anaesthesia. The patient ready for spinal anaesthesia will be judged only when he or she will show complete loss of pinprick sensation in femoral, obturator and lateral femoral cutaneous nerve distribution or VAS ≤4. After 30 mintues of fascia iliaca compartment block, sub arachnoid block will be performed in the sitting posture under strict aseptic precautions in the L3-L4 space using 25G Quincke needle with bupivacaine heavy 0.5% 3 ml. After giving spinal anaesthesia motor block is assessed. The surgery will be commenced after complete motor block.The zero time will  be considered on at completion of anaesthetic injection in fascia iliaca compartment block.

PRIMARY OUTCOME:

**Duration of analgesia:-**It is defined as from the time of completion of injection to administration of rescue analgesia to patient. Patients will be instructed to ask for supplementary analgesia when **VAS ≥**4 of 10 on the operated leg in the form of injection tramadol 100mg IV and at every 8 hours thereafter.

SECONDARY OUTCOMES:

**(1)**SENSORY BLOCK: Progression of sensory block will be assessed by using 22 G hypodermic needle and compared with the contralateral leg every 5 minutes after 30 minutes of injection.The grading of pin prick test will be determined as

0= normal sensation     1= blunted sensation (analgesia)    2= absence of sensation (anaesthesia)

Onset of sensory block will be time interval between end of local anaesthetic injection to the complete loss of pin prick sensation in the femoral, obturator and lateral femoral cutaneous nerve distribution.

**Duration of sensory block:-**It is defined as time interval from onset of sensory block to   disappearance of pinprick sensation in the femoral, obturator and lateral femoral cutaneous nerve distribution.

(2).   MOTOR BLOCK:-

Motor block will be assessed by modified bromage scale

Score

Criteria

|1

Complete block ( unable to move feet or knees).

|2

Almost complete block ( able to move feet only).

|3

Partial block ( just able to move knees).

|4

Detectable weakness of hip flexion while supine ( full flexion of knees).

|5

No detectable weakness of hip flexion while supine.

|6

Able to perform partial knee bend.

Onset of motor block will be defined as time interval from end of local anaesthetic injection to the inability of patient to move the leg of the operating limb.

Duration of motor block will be defined as time interval from onset of motor block to the recovery of leg motion of the operating limb.

(3). QUALITY OF ANALGESIA: Analgesia will be assessed using visual analogue scale scores at every 5 minutes till 30 minutes after the block in both group.

(4). VITAL PARAMETERS: Standard monitoring including HR, NIBP, SpO2will be evaluated every 5 minute after block placement till 30 minutes. After administration of spinal anaesthesia, HR, SBP, DBP, MAP, and SpO2 will be recorded every 15 min till the completion of surgery.

(5). ADVERSE EFFECTS: The untoward event in the perioperative period such as pain in foot on injection, blood aspiration during puncture, systemic toxicity of local anaesthetic drug, nausea, vomiting, haemodynamic disturbances(hypotension, bradycardia, tachycardia) or any side effect of the drug will be recorded and managed as follows:

1. Minor adverse effects that has not affected the patient’s lifestyle such as: minimal   pruritis, nausea, vomiting, drowsiness, shivering will be managed symptomatically without dose reduction/stopping.

2.  Bradycardia, defined as heart rate less than 50 beats/min or <20% from the baseline, will be treated with intravenous atropine 0.6 mg.

3.  Hypotension defined as a decrease in systolic blood pressure by more than 20% from baseline or MAP less than 60mmHg will be treated with bolus intravenous fluid and if not corrected will be treated further with incremental intravenous doses of Mephentermine 6 mg.

4.   In case of failure of block, patients will be excluded from the study.

(6). ADEQUACY OF BLOCK: The block will be considered

1.      Successful: If the sensory block in both femoral, obturator and lateral femoral cutaneous nerve distribution will complete within the first 30 minutes.

2. Delayed: If complete within 30 to 45 minutes of the performance, and

3. Incomplete If analgesic supplement will required for positioning of patients.

4. Failure if there will be an absence of anesthesia even 45 minutes after injection.

(7). PATIENT SATISFACTION :

Satisfaction with the anaesthetic technique will be evaluated 24 hours after surgery by using a two point score:-

1= Satisfactory, “if ever operated again in the future, I would accept the same anaesthetic procedure.â€

2 = Unsatisfactory, “if ever operated again in the future, I would prefer a different anaesthetic technique.â€