Postoperative analgesic efficacy of single-shot and continuous transversus abdominis plane block after laparoscopic cholecystectomy: A randomized controlled clinical trial.

STUDY OBJECTIVE: To compare the analgesic efficacy of ultrasound-guided single-shot and continuous transversus abdominis plane (TAP) block to that of IV-PCA in patients undergoing laparoscopic cholecystectomy. DESIGN: Prospective randomized controlled trial. SETTING: Post-anesthesia care unit and General ward. PATIENTS: 108 American Society of Anesthesiologist (ASA) physical status I-II patients undergoing laparoscopic cholecystectomy. INTERVENTIONS: Group A received IV-PCA; group B received both ultrasound-guided single-shot TAP block with 0.2% ropivacaine (20mL) and IV-PCA; and group C received continuous TAP block using an ultrasound-guidance-inserted indwelling catheter. In group C, infusion of 0.2% ropivacaine at a basal rate of 3mL/h, bolus dose of 4mL, and a lockout interval of 30min was maintained for 48h postoperatively. The primary outcome was evaluated analgesic efficacy using the numeric rating scale (NRS) for 48h postoperatively. Other outcomes included the number of patients requiring additional analgesics, patient satisfaction with postoperative pain control, and incidence of postoperative adverse events. MAIN RESULTS: Compared to other groups, group C had higher deep abdominal NRS at 1h postoperatively (P<0.05), and lower incidence of postoperative urinary retention (P<0.05). There were no significant intergroup differences in the number of patients requiring additional analgesics, and patient satisfaction with postoperative pain control. CONCLUSIONS: Compared to IV-PCA with or without single-shot TAP block, ultrasound-guided continuous TAP block provided similar analgesia in somatic pain and less analgesia in visceral pain. Moreover, the latter resulted in a lower incidence of postoperative urinary retention.

Nefopam Reduces Dysesthesia after Percutaneous Endoscopic Lumbar Discectomy.

BACKGROUND: Neuropathic pain, including paresthesia/dysesthesia in the lower extremities, always develops and remains for at least one month, to variable degrees, after percutaneous endoscopic lumbar discectomy (PELD). The recently discovered dual analgesic mechanisms of action, similar to those of antidepressants and anticonvulsants, enable nefopam (NFP) to treat neuropathic pain. This study was performed to determine whether NFP might reduce the neuropathic pain component of postoperative pain. METHODS: Eighty patients, who underwent PELD due to herniated nucleus pulposus (HNP) at L4-L5, were randomly divided into two equal groups, one receiving NFP (with a mixture of morphine and ketorolac) and the other normal saline (NS) with the same mixture. The number of bolus infusions and the infused volume for 3 days were compared in both groups. The adverse reactions (ADRs) in both groups were recorded and compared. The neuropathic pain symptom inventory (NPSI) score was compared in both groups on postoperative days 1, 3, 7, 30, 60, and 90. RESULTS: The mean attempted number of bolus infusions, and effective infused bolus volume for 3 days was lower in the NFP group for 3 days. The most commonly reported ADRs were nausea, dizziness, and somnolence, in order of frequency in the NFP group. The median NPSI score, and all 5 median sub-scores in the NFP group, were significantly lower than that of the NS group until postoperative day 30. CONCLUSIONS: NFP significantly reduced the neuropathic pain component, including paresthesia/dysesthesia until 1 month after PELD. The common ADRs were nausea, dizziness, somnolence, and ataxia.

Intravenous Nefopam Reduces Postherpetic Neuralgia during the Titration of Oral Medications.

BACKGROUND: The recently known analgesic action mechanisms of nefopam (NFP) are similar to those of anticonvulsants and antidepressants in neuropathic pain treatment. It is difficult to prescribe high doses of oral neuropathic drugs without titration due to adverse effects. Unfortunately, there are few available intravenous analgesics for the immediate management of acute flare-ups of the chronic neuropathic pain. The aim of this study was to determine the additional analgesic effects for neuropathic pain of NFP and its adverse effects during the titration of oral medications for neuropathic pain among inpatients with postherpetic neuralgia (PHN). METHODS: Eighty inpatients with PHN were randomly divided into either the NFP or normal saline (NS) groups. Each patient received a 3-day intravenous continuous infusion of either NFP with a consecutive dose reduction of 60, 40, and 20 mg/d, or NS simultaneously while dose titrations of oral medications for neuropathic pain gradually increased every 3 days. The efficacy of additional NFP was evaluated by using the neuropathic pain symptom inventory (NPSI) score for 12 days. Adverse effects were also recorded. RESULTS: The median NPSI score was significantly lower in the NFP group from days 1 to 6 of hospitalization. The representative alleviating symptoms of pain after using NFP were both spontaneous and evoked neuropathic pain. Reported common adverse effects were nausea, dizziness, and somnolence, in order of frequency. CONCLUSIONS: An intravenous continuous infusion of NFP reduces spontaneous and evoked neuropathic pain with tolerable adverse effects during the titration of oral medications in inpatients with PHN.

Effective analgesia with ultrasound-guided interscalene brachial plexus block for postoperative pain control after arthroscopic rotator cuff repair.

PURPOSE: Ultrasound (US)-guided continuous interscalene brachial plexus block (CBPB) is known to provide effective pain relief for arthroscopic rotator cuff repair. This study was conducted to compare analgesic efficacy and forearm muscle tone of the basal infusion rate and bolus dose of 0.2 % ropivacaine for US-guided CBPB with intravenous patient-controlled analgesia (IV-PCA). METHODS: In a prospective trial, 99 patients scheduled to undergo arthroscopic rotator cuff repair were divided into three groups. In groups A and B, an US-guided 17-gauge Tuohy needle was inserted into the interscalene brachial plexus. A loading dose of 10 ml 0.2 % ropivacaine was administered via the needle. A 19-gauge perineural catheter was then inserted through the needle and advanced to a depth of 1.5 cm beyond the needle tip between the C5 and C6 nerve trunks. After surgery, groups A and B received a continuous infusion of 0.2 % ropivacaine at 4 or 0 ml/h, a bolus of 0 or 4 ml, and a lockout time of 60 min through the catheter, respectively. Group C received IV-PCA. Pain scores and the forearm muscle tone of patients were compared using a numeric rating scale (NRS), rates of patients taking supplementary opioid analgesics, and manual muscle test (MMT) scoring. RESULTS: The NRS scores and rate of patients taking supplementary opioid analgesics in groups A and B were lower than those in group C after surgery. Groups A and B showed similar clinical efficacy. There were no significant differences in MMT scoring among the three groups. CONCLUSIONS: The bolus dose of 0.2 % ropivacaine using US-guided CBPB would provide equivalent analgesic efficacy comparable with the basal infusion and motor weakness comparable with IV-PCA after arthroscopic rotator cuff repair.