Andrea Perniola

Postoperative pain after abdominal hysterectomy: a double-blind comparison between placebo and local anesthetic infused intraperitoneally.

Abdominal hysterectomy is associated with moderate to severe postoperative pain. We randomly divided 40 patients (ASA status I–II) undergoing elective abdominal hysterectomy into 2 groups: group P received an infusion of normal saline 5 mL/h via a catheter placed intraperitoneally at the end of surgery, and group L received 0.25% levobupivacaine 12.5 mg/h (5 mL/h). Ketobemidone was administered IV via a patient-controlled analgesia pump as a rescue analgesic in all patients. The catheter was removed after 24 h. Incisional pain, deep pain, and pain on coughing were assessed 1, 2, 3, 4, 8, 16, and 24 h after surgery by using a visual analog scale. Ketobemidone consumption during 0–72 h was recorded. Time to sit, walk, eat, and drink; home discharge; and plasma concentrations of levobupivacaine were also determined. Pain at the incision site, deep pain, and pain on coughing were all significantly less in group L compared with group P at 1–2 h after surgery. After 4 h, the mean visual analog scale pain scores at rest and during coughing remained <3 cm during most time periods. Total ketobemidone consumption during 4–24 h was significantly less in group L compared with group P (mean, 19 versus 31 mg, respectively). A less frequent incidence of postoperative nausea, but not vomiting, was also found during 4–24 h in group L compared with group P (P < 0.025). Total and free plasma concentrations of levobupivacaine were small. We conclude that levobupivacaine used as an infusion intraperitoneally after elective abdominal hysterectomy has significant opioid-sparing effects.

A meta-analysis of the efficacy of wound catheters for post-operative pain management.

Local anesthetics (LA) are injected via catheters placed in surgical wounds for post‐operative analgesia. The primary aim of this systematic review was to assess whether LA reduce pain intensity when injected via wound catheters. A literature search was performed from Medline via PubMed, EMBASE and the Cochrane database from 1966 until November 2009. The search strategy included the following key words: pain, postoperative, catheters and local anesthetics. Two co‐authors independently read every article that was initially included and extracted data into a pre‐defined study record form. A total of 753 studies primarily fit the search criteria and 163 were initially extracted. Of these, 32 studies were included in the meta‐analysis. Wound catheters provided no significant analgesia at rest or on activity, except in patients undergoing gynecological and obstetric surgery at 48 h (P=0.03). The overall morphine consumption was lower (≈13 mg) during 0–24 h (P<0.001) in these patients. No significant differences in side effects were found, except for a lower risk of wound breakdown (P=0.048) and a shorter length of hospital stay (P=0.04) in patients receiving LA. A statistically significant heterogeneity was seen between the studies in most end‐points. LA injected via wound catheters did not reduce pain intensity, except at 48 h in a subgroup of patients undergoing obstetric and gynecological surgery. Rescue analgesic consumption was also lower in this group at 0–24 h. The magnitude of these effects was small and compounded by pronounced heterogeneity.

Efficacy of intra-articular bupivacaine, ropivacaine, or a combination of ropivacaine, morphine, and ketorolac on postoperative pain relief after ambulatory arthroscopic knee surgery: a randomized double-blind study.

Effective pain relief is important after diagnostic and therapeutic arthroscopic knee surgery to permit early discharge and improve comfort and mobility at home. The aim of this study was to assess the efficacy of bupivacaine, ropivacaine, or a combination of ropivacaine, morphine, and ketorolac injected intra-articularly for postoperative pain relief after arthroscopic knee surgery. Methods: Sixty-three healthy patients undergoing knee arthroscopy under local anesthesia (LA) were randomized to receive 1 of the following substances intra-articularly postoperatively: group B: 30 mL of bupivacaine (150 mg); group R: 30 mL of ropivacaine (150 mg); and group RMK: ropivacaine 150 mg, morphine 4 mg, and ketorolac 30 mg in normal saline (total volume 30 mL). Oral paracetamol 1g and tramadol 50 mg were used as rescue drugs. Postoperatively, pain was assessed at rest and movement, and side effects were recorded. The patients were asked to self-assess pain for 7 days and record analgesic consumption as well as activities of daily living (ADLs). Plasma concentration of LA was measured in another 8 patients. Results: All groups had excellent analgesia at 0 and 4 hours postoperatively. Group RMK had significantly lower visual analog pain score at rest at 8 hours and during movement at 8 and 24 hours compared with the other groups (P < .05). Group RMK required less paracetamol and tramadol on day 1 (P < .05), had less sleep disturbances because of pain, more patients were ready to work on days 1 and 2 (P < .05), and were more satisfied on days 1 and 4 to 7. Postoperatively, plasma concentrations of ropivacaine and lidocaine were far below known systemic toxic concentrations in all patients. Conclusion: Addition of morphine and ketolorac to ropivacaine intra-articularly enhances analgesic efficacy of LA, reduces postdischarge analgesic consumption, and improves ADLs without increasing side effects after ambulatory arthroscopic knee surgery.

Intraabdominal local anaesthetics for postoperative pain relief following abdominal hysterectomy : a randomized, double-blind, dose-finding study

Background and objective Local anaesthetics administered intraabdominally have been found to reduce analgesic requirements postoperatively after hysterectomy. This study was designed to assess the optimal dose of local anaesthetics for best pain relief. Methods Sixty patients undergoing abdominal hysterectomy were randomly divided into three groups to receive 10 ml h−1 infusion of levobupivacaine intraabdominally postoperatively for 48 h in a double-blind manner: group L, 7.5 mg h−1; group M, 12.5 mg h−1 and group H, 17.5 mg h−1. Pain intensity was measured using the numeric rating scale, ketobemidone consumption over 48 h was measured with a patient-controlled analgesia pump, recovery parameters, expiratory muscle strength, time to home readiness, plasma concentration of levobupivacaine and health-related quality of life were all measured at defined time points postoperatively. Results No differences were found between the active groups in pain intensity, recovery parameters or health-related quality of life. Pain intensity was maximal during 0–4 h and during coughing. Expiratory muscle strength decreased significantly during 0–4 h in all active groups, with no differences between the groups. Plasma concentration of levobupivacaine was below known toxic concentrations in humans, and no patient had symptoms of local anaesthetic toxicity. Health-related quality of life showed improved scores at 3 months after the operation compared with preoperative values, but no differences between the groups were found in any of the parameters. Conclusion Satisfactory analgesia can be achieved with low doses of levobupivacaine administered intraabdominally, except during the early postoperative period. No advantages were seen in this study when higher doses of levobupivacaine were administered as a continuous infusion for postoperative pain relief.

Postoperative pain after abdominal hysterectomy: a randomized, double-blind, controlled trial comparing continuous infusion vs patient-controlled intraperitoneal injection of local anaesthetic

BACKGROUND Local anaesthetics (LA) injected intraperitoneally have been found to decrease postoperative pain. This double-blind randomized study was performed comparing continuous infusion or patient-controlled intraperitoneal (i.p.) bolus injection of LA. The primary endpoint was supplemental opioid consumption during the first 24 postoperative hours. METHODS Two multi-hole catheters were placed intraperitoneally at the end of the surgery in 40 patients undergoing elective abdominal hysterectomy. The patients were randomized into two groups: Group P: patients self-injected 10 ml of levobupivacaine 1.25 mg ml(-1) via the i.p. catheter as needed, maximum once per hour, and had continuous saline infusion 10 ml h(-1) into the second catheter. Group C: patients received a continuous infusion of 10 ml h(-1) of levobupivacaine 1.25 mg ml(-1) intraperitoneally through one catheter and 10 ml saline as bolus as needed via the other. Ketobemidone was administered intravenously as rescue medication. RESULTS Total ketobemidone consumption during 0-24 h was lower in Group P compared with Group C (mean 23.1 vs 35.7 mg, P=0.04). No differences in the median pain scores were found between the groups. Earlier return of gastrointestinal (GI) function was found in Group P vs Group C (mean 1.5 vs 2.2 days, P<0.01), which also resulted in earlier home-readiness (mean 1.9 vs 2.7 days, P=0.04). CONCLUSIONS A statistically significant opioid-sparing effect was found when patient-controlled levobupivacaine was administered intraperitoneally as needed compared with continuous infusion. This was associated with a faster return of GI function and home-readiness. There was, however, a wide confidence interval in the primary endpoint, opioid consumption.

Intraperitoneal Local Anesthetics Have Predominant Local Analgesic Effect: A Randomized, Double-blind Study

Background:It remains unclear whether analgesia from intraperitoneal local anesthetics is via local or central mechanisms. This double-blind clinical trial tests the hypothesis that intraperitoneal local anesthetic is superior to continuous IV infusion for pain management. Primary outcome was morphine consumption during 0 to 24 h. Methods:Informed consent was obtained from 60 patients, age 30 to 75 yr, American Society of Anesthesiologists physical status I to II, undergoing abdominal hysterectomy. A computer-generated program randomized patients in parallel arms to group IV: continuous infusion of lidocaine 50 mg/h (10 ml) IV and saline 10 ml/h intermittently intraperitoneal; group IP: injection of lidocaine 50 mg/h (10 ml) once every hour intraperitoneally and continuous infusion of saline 10 ml/h intravenously; and group P (placebo): saline 10 ml/h both intravenously and intermittent intraperitoneal injection. Postoperative morphine consumption, pain intensity, recovery, home discharge, and lidocaine concentrations were measured. Results:Morphine consumption during 0 to 24 h was lower in group IP versus group IV, mean difference −22.6 mg (95% CI, 11.4 to 33.8; P < 0.01). No difference was seen between group IV and group P. The total mean plasma concentration of lidocaine in group IP was significantly lower than group IV, 0 to 4.5 h postoperatively (P = 0.03) with no evidence of systemic toxicity. Pain intensity and other recovery parameters were similar between the groups. Conclusion:The lower supplemental morphine consumption and plasma lidocaine concentration in group IP would confirm that the effects of local anesthetics are likely to be predominant via local intraperitoneal receptors or anti-inflammatory effects and not via central mechanisms alone.