Background: Tramadol, an analgesic, is a prodrug requiring bioactivation through cytochrome P450 enzymes (CYP450) to obtain O-desmethyltramadol (M1), its active metabolite. However, little is known on the African pharmacogenetic profile of tramadol metabolism. Hence, we aimed to study the biological efficacy of tramadol in an African population.Methods: This was a prospective cohort study over a 3-month period carried out at intensive care unit of a Cameroonian tertiary hospital. We enrolled patients with moderate-to-severe pain surgery, who had not been administered drugs metabolized by CYP450. Immediately after surgery, 2 mg/kg of tramadol was administered intravenously every 6 hours. Pain was assessed using the visual analog scale (VAS) within the first 24 hours. Vital signs and side effects were recorded. Plasma samples were collected at 3rd and 6th hours to assay tramadol and M1 using HPLC-UV.Results: We enrolled 30 patients with a mean age of 32 years operated for caesarean section, laparotomy and cancer surgery, under spinal and general anesthesia. Before administration of tramadol, the VAS was 6/10. The VAS decreased 4/10 to 1/10 between the 3rdand the 6th hour. There was a reduction of the respiratory rate of 3 breath cycles per minute as early as the 6th hour. Samples from 13 patients were analyzed. M1 was found in all patients; of which 4 had a slow metabolism and 3 had a faster metabolism.Conclusions: Overall there was good correlation between the clinical and biological analgesic efficacy of tramadol.

Background: The transversus abdominis plane (TAP) block is a regional anaesthetic technique that provides postoperative analgesia after abdominal surgery. This study was done to evaluate its feasibility and its efficacy on postoperative analgesia in patients undergoing total abdominal hysterectomy in a resource-limited setting. Methods: Ninety women, aged 30 to 68 years, classified ASA I and II, proposed for total abdominal hysterectomy indicated for uterine fibroids, were divided into two groups by randomization. Group A received a blind bilateral TAP block with ropivacaïne (1.5 mg/kg on each side) and after installation of sensory block, the general anaesthesia was carried out with propofol, fentanyl, rocuronium and isoflurane. Group B received only general anaesthesia with the same protocol like in group A. The success rate of TAP block was recorded in group A. In both groups, postoperative pain scores at rest, coughing efforts and postoperative analgesic consumption have been compared. Results: In Group A, the success rate of blind TAP block was 95.5 %. At the complete awakening of the patients, the mean visual analogue scale scores were significantly lower in patients in Group A compared to the patients in Group B (at rest 10.46 ± 0.92 versus 32.05 ± 20.81 mm, p=0.006 and with coughing 23.61 ± 12.04 versus 41.25 ± 18.50 mm, p=0.009). Compared to women in Group B, those in Group A had significantly lower visual analogue scale scores at rest, coughed less during the first 48 hours postoperatively and consumed significantly less ketoprofen (176.47 ± 65.40 mg versus 300.00 ± 41.40 mg, p =0.000) and no morphine (0 mg versus 15.19 ± 3.6, p=0.000). Conclusion: In a resource-limited setting, blind TAP block is feasible and should be practiced because it is easy to achieve. It significantly decreases postoperative pain and reduces the requirement for opioids and other analgesics.

Background: The efficacy of transversus abdominis plane (TAP) block has been demonstrated in postoperative analgesia, but few studies have evaluated its intraoperative effects. We aimed to describe the intraoperative hemodynamic and analgesic effects of pre-incisional TAP block in patients undergoing total abdominal hysterectomy. Methods: Seventy women proposed for total abdominal hysterectomy indicated for uterine fibroids, classified ASA I and II were randomized in a double-blinded model to Group A (n = 35) receiving bilateral ultrasound-guided TAP block with ropivacaine and Group B (n = 35) receiving bilateral ultrasound-guided TAP block with normal saline, followed by general anesthesia. The variations of the heart rate (HR) and mean arterial blood pressure (MABP) and intraoperative fentanyl consumption were studied. Results: At the arrival in the operating room, there was no significant difference in heart rate and mean arterial pressure noted in both groups. (HR: 85.38 ± 8.44 pulsations/min versus 86.30 ± 10.05 pulsations/min, p = 0.621; MABP: 94.97 ± 13.46 mmHg versus 96.36 ± 12.41 mmHg, p = 0.533). Before surgical incision, no statistically significant difference was detected between the two groups regarding the heart rate and the mean arterial blood pressure. After surgical incision, both the heart rate and mean arterial blood pressure were significantly higher in the Group B. There was a significant decrease in intraoperative fentanyl requirements in the Group A compared to the Group B (293.58 ± 60.59 mcg versus 449.44 ± 71.31 mcg, p < 0.001). Conclusion: Pre-incisional TAP block attenuates hemodynamic responses to surgical stress and decreases intraoperative fentanyl requirements How to cite this paper:

This was an open prospective study that was conducted from January 2012 to June 2016 at the Emergency Department of the Yaoundé Central Hospital in Cameroon. After taking approval from the National Ethics Committee, and obtaining a written informed consent from all patients, we included 64 SCD patients, aged above six years, and admitted for a vaso-occlusive bone crisis whose pain intensity assessed using the visual analogue scale (VAS) was greater than five. Patients who did not understand the VAS, those with contra-indications to the drugs used and patients

Patients and MethodsAfter approval by the National Ethical Committee and obtaining a signed informed consent from participants, we carried out a prospective simple-blinded randomised study at the Anaesthesiology and Intensive Care Unit of the Yaoundé Central Hospital from January 01, 2013 to December 31, 2015. We enrolled ASA I and II patients who were to undergo total abdominal hysterectomy for uterine fibroids and who could understand the visual analogue scale (VAS). We excluded patients with obesity (body mass index >30kg/m2), cardiovascular diseases, neuropsychiatric pathologies and those on longterm analgesics. Other exclusion criteria were the inability to comprehend the VAS, known allergy or a contra-indication to any