Postoperative sensitization and pain after cesarean delivery and the effects of single im doses of tramadol and diclofenac alone and in combination

Postcesarean analgesia: effective strategies and association with chronic pain

PURPOSE OF REVIEW

The management of postoperative pain after cesarean section slightly differs from that of the general surgical population, specifically women need to recover quickly to take care of their newborn baby. Optimal pain management is imperative for the success of immediate-term and long-term rehabilitation and this principle applies to obstetric patients. There is growing evidence that perioperative pain management has consequences extending well beyond the immediate recovery period. Unrelieved postoperative pain is a striking risk factor for the development of residual pain.

RECENT FINDINGS

A recent study has highlighted that chronic pain may be a significant clinical problem after cesarean section. Among the risk factors, recalls of severe acute postoperative pain led to the reconsideration of postoperative pain management after cesarean delivery. Current published data agree that drug combinations, that is, multimodal or balanced analgesia, are mandatory to achieve satisfactory and effective pain relief with reduced side effects.

SUMMARY

The use of balanced analgesia has significantly improved acute pain management after cesarean section. Future studies should extend their investigations beyond the first 48 h and consider the long-term effects of different analgesic regimens, that is, those that alter the development of residual pain.

Attenuation of C-reactive protein increases after exodontia by tramadol and ibuprofen

The anti-inflammatory effects of ibuprofen and tramadol were investigated by measuring C-reactive protein concentrations after removal of an impacted lower third molar. Forty-five American Society of Anesthesiologists Class I patients were randomly categorized into 3 equal groups according to postoperative analgesic medication. The first group received tramadol (100 mg every 8 hours), the second group received ibuprofen (400 mg every 8 hours), and the last group received half doses of both drugs in combination (50 mg tramadol every 8 hours and 200 mg ibuprofen every 8 hours). C-reactive protein was measured before surgery to exclude the presence of any preexisting inflammatory condition that might interfere with the study. C-reactive protein was also determined immediately after surgery and 72 hours postoperatively. At 72 hours, C-reactive protein had increased over postsurgery baseline by 123% in the tramadol group (P < .001), 84% in the ibuprofen group (P < .001), and only 37% in the combined analgesic group (P = .078). These results suggest that tramadol may produce supra-additive anti-inflammatory effects with ibuprofen after third-molar extractions.

The effect of preoperative intravenous use of tenoxicam: a prospective, double-blind, placebo-controlled study

In this study, we aimed to investigate the postoperative pain relief effect of preoperative tenoxicam usage in patients who undergo elective laparoscopic cholecystectomy or groin hernia repair. Eighty patients undergoing laparoscopic cholecystectomy or groin hernia repair procedures were randomized to receive either physiologic serum at 100 mL (group I, n = 40) or 20 mg iv tenoxicam (group II, n = 40) immediately before induction. Postoperative analgesic requirement, peroperative side effects and complications of drugs, operating time, post-operative mobilization time and pain score, hospitalization time, and patient pleasure were recorded. Postoperative pain was assessed by the visual analogue scale (VAS) on the recovery unit (RU), at 4, 8, and 24 h and every day at the same times in the morning. The RU median VAS score was also not different when Group 1 was compared with Group 2 (p = .97). However, the postoperative 4-h and 8-h median VAS score was significantly less (p = .01 and p = .03, respectively); first postoperative mobilization time was earlier in group 2 (p = .32). The median pain score and intramuscular analgesic requirement of patients were also reduced in Group 2 in postoperative day 1 (p = .015). The median duration of intramuscular analgesic requirement and total amount of intramuscular analgesic used in patients were also significantly less in Group 2 (p = .0001 and p = .0001, respectively). Thus, this study showed that preoperative use of iv tenoxicam is safe, simple, and effective for postoperative pain relief after laparoscopic cholecystectomy or inguinal hernia repair.

What’s new and novel in obstetric anesthesia? Contributions from the 2003 scientific literature

THE PREGNANT PATIENT: Age; maternal disease; prophylactic antibiotics; gastroesophageal reflux; obesity; starvation; genotyping; coagulopathy; infection; substance abuse; altered drug responses in pregnancy; physiological changes of pregnancy. THE FETUS: Fetal monitoring; intrauterine surgery. THE NEWBORN: Breastfeeding; maternal infection, fever, and neonatal sepsis evaluation. OBSTETRIC COMPLICATIONS: Embolic phenomena; hemorrhage; preeclampsia; preterm delivery. OBSTETRIC MANAGEMENT: External cephalic version and cervical cerclage; elective cesarean delivery; fetal malpresentation; vaginal birth after cesarean delivery; termination of pregnancy. OBSTETRIC ANESTHESIA: Analgesia for labor and delivery; anesthesia for cesarean delivery; anesthesia for short obstetric operations; complications of anesthesia. MISCELLANEOUS: Consent; ethics; history; labor support; websites/books/leaflets/journal announcements.

Spinal noradrenaline transporter inhibition by reboxetine and Xen2174 reduces tactile hypersensitivity after surgery in rats

Spinal noradrenaline (NA) released in response to noxious stimuli may play an important role in suppression of nociceptive transmission. Here, we investigated the efficacy of a competitive NA transporter inhibitor (reboxetine) and a noncompetitive NA transporter inhibitor peptide, Xen2174, isolated from the Pacific cone snail, to treat tactile hypersensitivity following paw incisional surgery. Male Sprague-Dawley rats were anesthetized, an incision of the plantar aspect of the hind paw was performed, and withdrawal threshold to von Frey filaments near the surgical site determined. Reboxetine (0.5-5 microg) and Xen2174 (0.3-100 microg) increased withdrawal threshold when injected 24h after paw incision, with a peak effect at 15-60 min, for Xen2174, an ED50 value of 0.64 microg. Administration of Xen2174 (3-30 microg) 15 min before incision also reduced hypersensitivity in a dose-dependent manner. Withdrawal threshold after the single 30 microg dose was greater than vehicle control even at 2, 3, and 5 days after incision. Doses <or=30 microg did not alter spontaneous behavior. The anti-hypersensitivity effect of 10 microg of Xen2174 was totally blocked by the alpha2-adrenoceptor antagonist, idazoxan, and partially blocked by the muscarinic antagonist, atropine. These data suggest that selective NA transporter inhibition suppresses post-incisional hypersensitivity through a different mechanism from that of neuropathic pain, since we previously reported that reversal of hypersensitivity by intrathecal clonidine, an alpha2-adrenoceptor agonist, following spinal nerve ligation is completely blocked by intrathecal atropine. Finally, these data suggest that intrathecal administration of Xen2174 at the time of spinal anesthesia might produce postoperative analgesia in humans.