Bilateral transversus abdominis plane (TAP) block with 24 hours ropivacaine infusion via TAP catheters: A randomized trial in healthy volunteers.

BACKGROUND: The analgesic effect of a TAP block has been investigated in various surgical settings. There are however limited information about block level and block duration. Furthermore, there is a lack of information about continuous TAP block after ultrasound-guided posterior TAP blocks.The aim of this double-blind randomized study was therefore to investigate the effect of an ultrasound-guided posterior TAP block with 24 hours local anesthetic infusion via a TAP catheter. METHODS: In this randomized study 8 male volunteers received a bilateral TAP block (20 mLs 0.5% ropivacaine) and were allocated to receive active infusion (ropivacaine 0.2% 5 mL/hr) via a TAP catheter on one side and placebo infusion on the other side. PRIMARY OUTCOME: Dermatomal sensory block involvement after 24 hours evaluated with pinprick. SECONDARY OUTCOMES: Sensory block involvement evaluated with cold test and heat-pain detection thresholds (HPDT) on the abdominal wall. Assessment points: 15 min before block performance and 1, 4, 8, 12 and 24 hours after block performance. RESULTS: The TAP block primarily involved sensory changes in the Th10 to Th12 dermatomes. On the placebo side there was a decrease in extension beginning at 4-8 hours after block performance and with no detectable effect beyond 12 hours. Median number of dermatomes anesthetized (pinprick) at 24 hours after block performance was 1.5 (0-3) on the active side compared with 0 (0-0) on the placebo side (P = 0.039).There were no statistical significant between-side differences in HPDT measurements at 24 hours after block performance. CONCLUSIONS: The spread of sensory block following ultrasound-guided posterior TAP block is partly maintained by a continuous 24 hour ropivacaine infusion through a TAP catheter. TRIAL REGISTRATION: The study was registered at NCT01577940.

Multimodal analgesia with gabapentin, ketamine and dexamethasone in combination with paracetamol and ketorolac after hip arthroplasty: a preliminary study.

BACKGROUND AND OBJECTIVE: It has been hypothesized that combinations of analgesics with different mechanisms of action may reduce or even prevent postoperative pain. We, therefore, investigated the analgesic effect of gabapentin, dexamethasone and low-dose ketamine in combination with paracetamol and ketorolac as compared with paracetamol and ketorolac alone after hip arthroplasty. METHODS: In this double-blind study, 42 patients were randomly assigned to either a combination group [gabapentin 1200 mg+dexamethasone 8 mg+ketamine (0.15 mg kg(-1))+paracetamol 1 g+ketorolac 15 mg] or a control group (placebo+paracetamol 1 g+ketorolac 15 mg). The medication was given preoperatively except for ketorolac, which was given at the end of surgery. Postoperative pain treatment was paracetamol 1 gx3; ketorolac 15 mgx3; and patient-controlled intravenous morphine. Morphine consumption, pain intensity at rest and during mobilization, nausea and vomiting, sedation, dizziness, hallucination and consumption of ondansetron were recorded 2, 4 and 24 h after operation. A P value of less than 0.05 was considered statistically significant. RESULTS: Morphine consumption was not significantly different between groups (P=0.085). Overall pain scores were improved in the combination group as compared with the control group both at rest (P=0.042) and during mobilization (P=0.027). In the combination group, individual pain score above 30 mm on a 100 mm visual analogue scale was almost eliminated. The incidence of side effects did not differ between the groups. CONCLUSION: Preoperative gabapentin, dexamethasone and ketamine combined with paracetamol and ketorolac reduced overall pain scores in patients after hip arthroplasty as compared with paracetamol and ketorolac alone. Morphine consumption was not reduced.

Effect of Gabapentin on morphine demand and pain after laparoscopic sterilization using Filshie clips. A double blind randomized clinical trial.

BACKGROUND: A considerable number of patients require opioids during recovery after laparoscopic sterilization. This implies nausea, dizziness and sedation and increases the number of unplanned admissions. Gabapentin has shown excellent postoperative analgesic effect in a number of recent studies with few side effects. This study was designed to test whether gabapentin given preoperatively can reduce the number of patients needing morphine in the recovery period. METHODS: 80 females scheduled for laparoscopic sterilization using Filshie clips were randomized to two treatment groups (Gaba group and control group). All patients received lornoxicam 8 mg p.o. 30 min. before the procedure. Patients in the Gaba group received gabapentin 1200 mg p.o. and patients in the control group received placebo capsules prior to the procedure. All patients were anesthetized according to a protocol, using remifentanil and propofol. Postoperative analgesia was obtained with patient controlled infusion of morphine. Pain, nausea, dizziness and sedation were scored at 2 and 4 hours after end of anesthesia. The expenditure of morphine was the primary measure for the effect of analgesia and the number of patients demanding morphine was the primary endpoint. RESULTS: Three patients were excluded because of procedural errors and one because of conversion to open surgery. 38 patients completed the study in each group.32 (84%) patients in the gabapentin group and 37 (97%) patients in the control group did require morphine in the recovery period. (p = 0,049). There was no significant difference between mean morphine consumption, pain scores and frequency of adverse effects (nausea, dizziness, sedation and vomiting) CONCLUSION: The postoperative analgesic effect of gabapentin given preoperatively was confirmed in this study. For this procedure, with pain predominantly in the immediate recovery period, and of less intensity than after major surgical procedures, the effect demonstrated is much less pronounced than in similar studies of major surgery. General use of gabapentin as analgesic for laparoscopic sterilization is not supported by this study. TRIAL REGISTRATION: Current Controlled Trials ISCRTN39209275.