Effect of Morphine, Tramadol, and Ketorolac on Postoperative Stress and Immune Responses

Sixty patients aged (20-60 years), weighting (50 -75 Kg), with American Society of Anesthesiologists (ASA) physical status I or II scheduled for modified radical mastectomy surgery under general anesthesia were enrolled in this prospective clinical study. The Ethics Committee of South Egypt Cancer Institute (SECI), assuit University, assuit, Egypt approved the study. Informed written consent was obtained from each patient to be enrolled in this study.

Patients with known allergy to opioids or Non Steroidal Anti-inflammatory drugs NSAIDs, with gastric or duodenal ulcer, on radiotherapy or chemotherapy, received blood transfusion before the surgery or preoperative NSAIDs, steroid or opioid medications 48 hours prior to operation were excluded.

All patients were taught how to evaluate their own pain intensity using the visual analogue scale (VAS) scored from 0 to 10 (where 0 = no pain and 10 = the worst pain imaginable). Both the patient and the anesthetist involved in the study were kept blinded to group assignment. Randomization codes were not decoded till the end.

No pre-medications were given. Basic monitoring probes (ECG, non invasive blood pressure, end-tidal carbon dioxide, pulse oximetry and temperature) were applied. base line VAS, sedation score, systolic and diastolic blood pressure, heart rate, respiratory rate and oxygen saturation were assessed before the beginning of surgery. Venous blood sample was taken for assessment of the base line stress hormones (cortisol, prolactin) and immune response (cluster of differentiation (CD) 3, 4, 8 and 56), General anesthesia was induced with I.V. fentanyl 1 μg/kg, thiopental 5mg/kg. Endotracheal intubation was facilitated by cis-atracurium 0.15 mg/kg, and was maintained with isoflurane 1.5-1.7 MAC, cis-atracurium 0.03 mg/kg and controlled ventilation in a ventilation parameters that maintain normocapnia (35- 45 mmHg). Neuromuscular block was antagonized by neostigmine 50µg/kg and atropine 20µg/kg. Venous blood sample was taken for assessment of stress hormones (cortisol, prolactin) and immune response (CD3, CD4, CD8 and CD56) immediately postoperatively after extubation in the operative room before the analgesic drug administration. VAS, sedation score, systolic and diastolic blood pressure, heart rate, respiratory rate and oxygen saturation were also assessed. Patients were allocated according to computer-generated randomization tables into one of three groups of 20 patients each to receive:

Group I: (n=20) received IV 0.1mg/kg morphine sulphate (morphine sulfate ®, Misr CO Pharma).

Group II: (n=20) received IV 2 mg/kg tramadol Hcl (tramadol ®, October Pharma S.A.E).

Group III: (n=20) received IV 30 mg ketorolac tromethamine (ketorolac ®, Amriya Pharma).

Patients were transferred to the post anesthesia care unit (PACU). During this period observation of heart rate, systolic and, diastolic blood pressure, respiratory rate, oxygen saturation and VAS were recorded at 2, 4, 6, 8, 12, 18 and 24hrs postoperatively. In addition, side effect such as nausea, vomiting, respiratory depression and sedation (using sedation score from 0 to 4, where 0= awake, 1= easily aroused, 2= awaken after verbal stimulation, 3=awaken after tactile stimulation and 4= not arousable) were recorded and treated. Another venous blood samples were taken for assessment of stress hormones at 40 mins, immune response at 90 mins and for both stress hormones and immune responses at 24 hours later. In order to keep VAS ≤ 3 for 24hours postoperative, repeated doses of the same analgesic medications (morphine to the first group, tramadol to the second group, and ketorolac to the third group) were given all over the observation period at the same doses.

Determination of serum cortisol and prolactin levels was done by fully automated ELISA (enzyme linked immunosorbent assay) (EVOLIS®, Biorad, Germany). Expressions of (CD3+, CD4+, CD8+ and CD56+) in blood samples were measured as percentages of total lymphocytes by fluorescence activated cell sorter (FACS) calibur flow cytometry with cell quest software (Becton Dickinson Biosciences, USA). Anti-human IgG was used as an iso type-matched negative control for each sample. Forward and side scatter histogram was used to define the lymphocyte population. Then, the percentages of CD3+, CD4+, CD8+ and CD56 were assessed in lymphocytes population. The positive percentage was >20%