Comparison of thoracic epidural anaesthesia with general balanced anaesthesia for perioperative management of modified radical mastectomy - a randomized control trial

Breast cancer isthe most common cause of cancer in women. Surgery, pain, opioid use, stress hormones andimmune-suppression are suspected to have an influence on cancer recurrence.Animal studies have shown that opioids, volatile anesthetics, thiopental,and ketamine, could inhibit natural killer cell (NK) activity and cause cancermetastasis. But propofol has anti-inflammatory properties and aids in thepreservation of NK cell activity.

Breastsurgeries are commonly performed under balanced general anaesthesia along withregional plane blocks to reduce the consumption of opioids. However,limitations include technical difficulties and increased possibilities ofcomplications like pneumothorax. Moreover use of blocks alone as an anaesthetictechnique is not feasible. We hypothesized that the use of thoracic epiduralanaesthesia would provide complete anaesthesia for performing modified radicalmastectomy thereby reducing the postoperative complications, ICU and hospitalstay and reduced health care cost. Primary objective is to comparepost operative pain score between the two groups. Secondary objectives includeincidence of postoperative hoarseness of voice, cough, PONV, intra operativeand postop analgesic requirement, duration of hospital and ICU stay,anaesthetic cost, patient and surgeon satisfaction.

Methods

Thisprospective, randomised study will be conducted after obtaining approval fromhospital ethical committee, clinical trial registryof India (CTRI) and informed written consent from patients.  Patients aged 18–60 years, of theAmerican Society of Anaesthesiologists (ASA) physical status 2–3 undergoing unilateralmodified radical mastectomy will be included in this study. Patients with anycontraindications to epidural, infection at the site of the planned epiduralplacement, any coagulation disorders, or known allergy to lignocaine or anyanaesthetic drug will be excluded from the study.

Thepatients will be randomly assigned into two equal groups, G and E based oncomputer-generated random sequence of numbers. Concealment will be achieved byclosed envelope technique.  Patients inboth groups will receive oral ranitidine 150 mg,metoclopramide10 mg, and alprazolam 0.25 mg on the night before surgery andranitidine 150 mg and metoclopramide 10 mg on the morning of surgery. In theoperation theatre, intravenous (IV) cannula will be inserted and monitoringwith electrocardiography, noninvasive blood pressure monitor, and pulse‑oximeter will be done. Standardgeneral anaesthesia protocol will be followed in group G.Patients will be preoxygenated with 100% O2; glycopyrrolate 0.2 mg,midazolam 2 mg, and fentanyl 2 µg/kg will be given intravenously. They willthen be induced with IV propofol 1.5–2.5 mg/kg till there is loss of responseto verbal Command and patient becomes apnoeic. Classic LMA size 3/4 will beinserted after full deflation. Patient will be maintained on O2, N2Oand isoflurane 0.5%–1.5%. LMA cuffs will be filled with 20/30 ml of room air.Patients will be maintained on spontaneous ventilation.

Patientsin group E, will be placed in left lateral position and under strict asepticprecautions epidural catheter will be placed in T5-T6 using18 gauge Tuohy needle under mild sedation with 10-20mg of titrated doses ofpropofol. Supplemental oxygen 5 L/min will be administered through a face mask for the entire duration of the surgery. The epidural catheter will beinserted 3-5cm into the epidural space. A test dose of 3 mL of  2% lignocaine with epinephrine 1:200,000 will be given to excludE intravascular orintrathecal injection.  Titrated dose of 5–8 mL of 2% lignocaine will be injected through the catheter andanaesthetic dermatomal levels achieved will be determined by a pinprick. Followingthis, a titrated infusion of the same drug will be maintained.

  Towardthe end of the surgery, IV ondansetron 4 mg and IV paracetamol 1 g will be given topatients in both groups and thesurgeon will give local infiltration with 5–10 mL of  2% lignocaine. Ingroup G, on completion of the surgery, LMA will be removed after suctioning anddeflating the cuff. The epidural catheter is removed at the end of surgery ingroup E. Four hours after surgery all patients will receive oral paracetamol650 mg 8th hourly. Patients will be given rescue analgesia with IV ketorolac1mg.kg−1 if the patient complained of pain. The total dose ofketorolac given in the first 24 h will be noted for both groups.

Postoperativesore throat, cough, hoarseness, VAS scores, nausea, vomiting, monitoring willbe done in the Intensive Care Unit (ICU) by the anaesthetist who will beblinded to the group allocation and the responses will be noted at 0, 2, 4, 12,and 24 h. The patients will be asked to grade POST, cough, and hoarseness usinga predefined category scale with scores 0–3 and nausea vomiting will be gradedas 0-2. Totalintra-operative, as well as post-operative opioid consumptions, will bedocumented. The incidence of postoperative side effects (e.g.,nausea, vomiting, dizziness), duration of the postanesthesia care unit andhospital stays, was documented.Pain intensity will be assessed using numerical pain scale 0–10 (0=no pain to10=worst imaginable pain). Postanesthesia recovery was evaluated by using themodified Aldrete score system involving the level of consciousness, motoractivity, respiration, and circulation. An Aldrete score of 10 (patient fullyawake, oriented, and comfortable, with stable cardiovascular and respiratorysigns) will be used for discharge from the postanesthesia care unit. Homereadiness was assessed by the operating surgeon.  Patient satisfaction with the anaestheticexperience was noted. All were asked to rate their overall experience with theanaesthetic technique as “satisfactory†or “unsatisfactory.â€We will also becomparing the anaesthesia charges between the two groups.