Effect of intravenous Lignocaine and Dexmedetomidine infusion based anaesthetic technique on anti-tumor immunity as assessed by transforming growth factor-β levels in adult patients undergoing surgery for Oral cancer: a prospective randomized study.

AIMS AND OBJECTIVES:

AIM**:** To compare the effects of lignocaine and dexmedetomidine infusion based anaesthesia technique on anti-tumor immunity as assessed by TGF-β in patients of oral Cancer undergoing surgery.

PRIMARY OBJECTIVE:

To detect the difference in the Post-operative Serum TGF-β levels in patients receiving lignocaine infusion and dexmedetomidine infusion based anaesthesia in patients of Oral Cancer undergoing surgery.

SECONDARY OBJECTIVE:

1.   To detect the difference in perioperative systemic inflammation and anti-tumour immunity: change   between preoperative and postoperative T-helper cell profile, IL-6, Neutrophil Lymphocyte ratio  (NLR), Platelet Lymphocyte ratio (PLR), Monocyte Lymphocyte Ratio (MLR) and modified   Glasgow Prognostic Score (m GPS).

2.  To compare incidence of peri-operative complications (pruritus, nausea, vomiting, bradycardia,    hypotension) among the study groups.

3.  To compare the total opioid consumption in perioperative period among the study groups.

 METHODOLOGY:

Design of the study: Prospective, Randomized trial

Inclusion criteria:

1.   Age 18 -70 years.

2.   Patients undergoing surgery for Oral cancer.

3.   ASA I, II, III.

Exclusion criteria:

1.    Patient refusal.

2.    Allergy to any of the study drugs.

3.    Chronic kidney and liver disease.

4.    Blood transfusion in perioperative period.(30 days prior to surgery and Up to 24 hrs postoperative period)

5.   Atrioventricular conduction disorders.(Either with pacemaker or on antiarrhythmics)

6.   Heart failure on treatment with beta blockers.

7.   Patients with chronic pain preoperatively already receiving Opioids

Preoperative visit:

Recruitment of the patients for the study will begin after getting approval from the institutional scientific and ethics committee. Informed written consent will be obtained. All the selected patients will undergo a routine pre-anaesthetic check-up. All the routine investigations pertaining to anaesthesia management will be done.On the day of surgery, upon arrival at the operation theatre, I.V. line will be secured and routine monitors (Spo2, NIBP, and E.C.G,) will be attached. Baseline heart rate (HR) and blood pressure (BP) will be noted. A blood sample for preoperative neutrophil lymphocyte ratio (NLR), Monocyte Lymphocyte Ratio (MLR), platelet lymphocyte ratio (PLR), CRP, IL-6, and TGF beta with T-helper cell profile will be sent and noted.

Randomization and allocation concealment:

Patients will be randomly allocated into three groups “A†, “B†and “C†using a computer generated random numbers sequence and allocation concealed in a sequentially numbered opaque envelope.

Intraoperative Management:

For Group A, after adequate preoxygenation, an initial bolus dose of opioid Injection fentanyl (2 µg/kg) will be administered. Anaesthesia will be induced with injection propofol (2-2.5 mg/kg titrated to effect of loss of consciousness) and followed by muscle relaxant Injection rocuronium (0.6 mg/kg I.V bolus) after checking ventilation. Intubation plan and technique will be as per anaesthesia provider attending the case. For patients of this group intraoperative sedo-analgesia will be provided with Inj. fentanyl (1 µg/kg bolus) as required. Total opioid consumption will be noted.

For Group B, after adequate preoxygenation, an initial bolus dose of opioid Inj fentanyl (2 µg/kg) will be administered. Anaesthesia will be induced with i.v propofol (2-2.5 mg/kg titrated to effect of loss of consciousness and followed by muscle relaxant rocuronium (of 0.6 mg/kg I.V bolus). Intubation plan and technique will be as per anaesthesia provider attending the case. This will be followed by starting Injection lignocaine (preservative free, trade name –XYLOCARD) 2% intravenous infusion at the rate of 1.5 mg/kg/hr. If heart rate and/or blood pressure rises from baseline by 20%, Inj Fentanyl (1 µg/kg) may be given for sedo-analgesia. Total opioid consumption will be noted.

For Group c, after adequate preoxygenation, an initial bolus dose of opioid Inj fentanyl (2 µg/kg) will be administered. Anaesthesia will be induced with i.v propofol (2-2.5 mg/kg) titrated to effect of loss of consciousness and followed by muscle relaxant rocuronium (of 0.6 mg/kg I.V bolus). Intubation plan and technique will be as per anaesthesia provider attending the case. This will be followed by infusion of Inj. Dexmedetomidine (loading dose 1 µg/kg over 10 minutes followed by maintenance dose 0.5 µg/kg/hour). If heart rate and/or blood pressure rises from baseline by 20%, Inj Fentanyl (1 µg/kg) may be given for sedo-analgesia. Total opioid consumption will be noted.

For all the patients, intraoperative maintenance of anaesthesia will be done with Oxygen+ air + sevoflurane + rocuronium infusion. All patients will receive Inj. paracetamol 15mg/kg I.V. and Inj. diclofenac 1.5 mg/kg I.V. as part of multimodal analgesia towards end of the surgery. For patients of group B and C the respective infusions will continue for 24 hours and then stopped.

Intraoperative HR, Spo2, ECG, invasive/non-invasive BP, and temperature will be measured, urine output will be monitored. Patients will be mechanically ventilated in a volume-controlled mode to maintain tidal volumes of 6-8 ml/kg, at respiratory rates (10- 14 breaths/min) to maintain a target end-tidal carbon dioxide (EtCO2) partial pressure of 35- 40 mmHg with a positive end-expiratory pressure of 5 mmHg. Any hypotensive episodes, defined as a decrease in mean arterial pressure by 20% of baseline value, will be treated by i.v bolus doses of 6 mg of Mephenteramine. Blood loss will be replaced as per institutional protocol. Pain will be managed by multimodal analgesia.

Postoperative Management:

The patients will be shifted to the ICU and electively mechanically ventilated as per the institutional protocol. ICU sedation will be provided with Inj. Midazolam infusion (0.5mg-2mg /hr) and Inj fentanyl (0.5µg-2µg/kg/hr). Sedation will be switched off prior to planned extubation. Pain will be managed with multimodal analgesia required to keep an NRS score <3/10. In the post-operative period all patients will receive Injection paracetamol (15mg/kg) intravenous TDS as part of post-operative analgesia. Inj. diclofenac 1.5 mg/kg will be used for rescue analgesia if needed.

Incidence of pruritus, nausea, vomiting, bradycardia, hypotension and any other complication/event will be noted in all the study groups and treated as per institutional protocol. Total 24 hour consumption of opioids will be noted. 24 hours after the surgery, a blood sample would be sent for post-operative neutrophil lymphocyte ratio (NLR), Monocyte Lymphocyte Ratio (MLR) and platelet lymphocyte ration (PLR), CRP, IL-6 and TGF beta with T-helper cell profile.