Chen-Jung Lin

Prophylactic intravenous ondansetron reduces the incidence of intrathecal morphine-induced pruritus in patients undergoing cesarean delivery.

Pruritus is a common side effect of intrathecal morphine injection for postoperative pain control. Its incidence is especially high in patients undergoing cesarean delivery. We investigated the effectiveness of ondansetron in preventing intrathecal morphine-induced pruritus in such patients. We included 60 consecutive nonbreastfeeding women who were scheduled for elective cesarean delivery. After the administration of spinal anesthesia with bupivacaine and intrathecal morphine 0.15 mg injection, the patients were randomly divided into three groups. Group 1 received placebo (normal saline) IV injection, Group 2 diphenhydramine 30 mg IV injection, and Group 3 ondansetron 0.1 mg/kg IV injection. The incidence of pruritus was significantly lower in the ondansetron group (25%) when compared with that in the placebo group (85%) and in the diphenhydramine group (80%) (both P < 0.05). The postoperative pain score and time to flatus passage were not significantly different among the three groups. There were no headache or extrapyramidal signs associated with ondansetron use. In conclusion, ondansetron prophylaxis significantly reduced the incidence of intrathecal morphine-induced pruritus in patients undergoing cesarean delivery. Implications Ondansetron prophylaxis significantly decreases the incidence of pruritus, a common side effect of intrathecal morphine used to treat postcesarean delivery pain.

The addition of morphine prolongs fentanyl-bupivacaine spinal analgesia for the relief of labor pain.

The combination intrathecal fentanyl (25 μg) and bupivacaine (2.5 mg) provides effective labor analgesia for approximately 90 minutes. The purpose of this prospective, randomized, double-blinded investigation was to determine if the addition of morphine (150 μg) to the intrathecal combination of fen

Analgesic Effect of Lidocaine Patch 5% in the Treatment of Acute Herpes Zoster: A Double-Blind and Vehicle-Controlled Study

Background and Objectives: Although lidocaine patch 5% has been widely used for postherpetic neuralgia, its analgesic effect on the intense pain associated with acute herpes zoster has not been investigated because of its potential hazard to damaged skin. Methods: Forty‐six patients suffering from moderate to severe pain caused by acute herpes zoster infection (within 4 weeks of onset) were enrolled in a randomized, double‐blind, vehicle‐controlled, parallel study. Lidocaine patch 5% or vehicle patch were applied to the intact portion of the painful skin area without blisters at 12‐hour intervals twice a day for 2 consecutive days. Analgesic efficacy and side effect profiles were assessed before and 48 hours after patch application. Results: We found that both groups of patients experienced significant pain relief during rest and movement. Differences of mean reduction of pain intensity between the two groups were 14.7 (4.7‐24.8, P = 0.005) during rest and 10.4 (1.6‐19.3, P = 0.007) during movement, favoring the lidocaine patch. The lidocaine patch produced a greater percentage change in a patients global impression than the vehicle patch. The incidence and severity of adverse events were low with both treatments. Conclusions: This study demonstrates that lidocaine patch 5%, applied twice a day, could serve as a well tolerated and effective modality to relieve moderate to severe pain associated with acute herpes zoster presumably through its pharmacological action and physical barrier effect on sensitized skin.

Does the Suggested Lightwand Bent Length Fit Every Patient?The Relation between Bent Length and Patient's Thyroid Prominence–to–Mandibular Angle Distance

Background To date, no study has explored the effect of bent length on lightwand intubation. For successful intubation in daily practice, the authors found that bent length should be approximated to the patients thyroid prominence-to-mandibular angle distance (TMD), but some patients have a TMD much shorter than the suggested bent length range. The purposes of this study were to understand TMD distribution in adults and to test the influence of bent length on lightwand intubation. Methods The TMD, airway, and demographic data of 379 patients were collected. To test the bent length influence, patients were enrolled in group A (158 patients, TMD ≤ 5.5 cm) and group B (131 patients, TMD > 5.5 cm) and were intubated randomly using the lower (6.5 cm) and upper (8.5 cm) limits of the suggested range. Success rate and lightwand search time were compared. Results In group A, the success rate was 98.8% with 6.5-cm bent length and 78.2% with 8.5-cm bent length (P < 0.05). Search times were 5.7 ± 2.90 and 8.9 ± 5.80 s with 6.5- and 8.5-cm bent length, respectively (P < 0.01). In group B, there was no statistical difference in success rate and search time between 6.5- and 8.5-cm bent length. Conclusion The suggested range was suitable for patients in group B (TMD > 5.5 cm). However, in group A (≤5.5 cm), the large discrepancy between the upper limit of the suggested range and this TMD caused difficulty in lightwand intubation. A 6.5-cm bent length is more suitable than an 8.5-cm bent length in these patients.

Combination of Low-dose Nalbuphine and Morphine in Patient-controlled Analgesia Decreases Incidence of Opioid-related Side Effects

BACKGROUND/PURPOSE The addition of ultra-low-dose naloxone to patient-controlled analgesia (PCA) with morphine reduces opioid-related side effects. Nalbuphine, a mixed opioid agonist-antagonist, may be able to attenuate opioid-related side effects. The goal of the present study was to investigate the effect of combined low-dose nalbuphine and morphine in PCA for postoperative pain control after gynecological surgery. METHODS This randomized, double-blind, controlled study enrolled 174 female patients who were undergoing total abdominal hysterectomy, myomectomy, or ovarian tumor excision. In the control group, the PCA formula was 1 mg/mL pure morphine. In the study group, the PCA formula was 1 mg/mL morphine and 10 microg/mL nalbuphine (1:100). Numerical rating score, PCA requirement, nausea, vomiting, use of antiemetics, pruritus, use of antipruritics, and opioid-related adverse events were investigated at 1, 2, 4, and 24 hours postoperatively. RESULTS One hundred and sixty-nine patients completed the study: 86 in the control group and 83 in the study group. The incidence of nausea was lower in the study group (41%) than in the control group (65%). The incidence of vomiting, use of antiemetics, pruritus, and use of antipruritics did not differ between the two groups. The numerical rating pain score and PCA requirements were not significantly different between the two groups. CONCLUSION Combination of low-dose nalbuphine and morphine in PCA decreases the incidence of opioid-related nausea, without affecting the analgesia and PCA requirement. This novel combination can improve the quality of PCA used for postoperative pain control after gynecological surgery.

Propofol attenuates the decrease of dynamic compliance and water content in the lung by decreasing oxidative radicals released from the reperfused liver.

BACKGROUND: Remote pulmonary injuries after hepatic reperfusion are frequently caused by reactive oxygen species (ROS)-induced damage. The choice of anesthetics may affect the balance between oxidants and antioxidants, and propofol, a commonly used anesthetic, has an antioxidant effect. In this study, we developed a model to study pulmonary function with hepatic ischemia/reperfusion (I/R) manipulation, with the aim of defining remote pulmonary dysfunction after hepatic reperfusion and determining if propofol affects this dysfunction by altering ROS production from the liver or lungs. METHODS: Adult male rats weighing 160–250 g were randomly divided into four groups according to the type of surgery (sham or I/R) and the anesthetic administered (pentobarbital or propofol). To induce I/R, the portal vein and hepatic artery to the left and medial lobes of the liver were clamped. All of the measurements were done after 5 h of reperfusion, after 45 min of ischemia. Pulmonary function after hepatic I/R was determined by dynamic compliance, resistance and wet-to-dry ratio, and by histopathology. Hepato-cellular injuries were confirmed by alanine aminotransferase, whereas ROS production was measured from the inferior vena cava, jugular vein, and carotid artery. Products of lipid peroxidation, thiobarbiturate acid reactive substances and malondialdehyde, were measured in lung and hepatic tissues. RESULTS: Remote lung injury after hepatic I/R was shown by a significant decrease of Cdyn, and increases in resistance and the wet-to-dry ratio. ROS production was significantly increased and was highest in samples from the inferior vena cava. Thiobarbiturate acid reactive substances and malondialdehyde in the liver and serum alanine aminotransferase were significantly increased only in the I/R+pentobarbital group. All of the changes were significantly attenuated in the I/R+ propofol group (P = 0.05). With propofol infusion, there was decreased ROS production from the reperfused liver, with less hepato-cellular injury, followed by well-maintained pulmonary function. CONCLUSION: Remote pulmonary dysfunction and reperfusion injury in the liver were demonstrated in our rat model, as well as massive ROS production and lipid peroxidation. Propofol infusion attenuated remote pulmonary injury by lessening oxidative injury from the reperfused liver.

Differential analgesic effect of tenoxicam on the wound pain and uterine cramping pain after cesarean section.

BackgroundNonsteroidal anti-inflammatory drugs (NSAIDs) are widely used to enhance opioid analgesia in the acute pain service. The question, however, of whether NSAIDs produce a similar extent of potentiation among different types of pain, has not been thoroughly investigated. Materials and MethodsA randomized, placebo-controlled, double-blind study was performed to characterize the analgesic effect of tenoxicam, a long-acting NSAID, on resting wound pain, evoked wound pain, and uterine cramping pain after cesarean section. Saline (n = 48) or 20 mg tenoxicam (n = 45) was intravenously injected immediately after clamping the umbilical cord. All patients were instructed to obtain maximal postoperative analgesia by intravenous patient-controlled morphine. ResultsTenoxicam profoundly reduced the intensity of uterine cramping pain (3.6 [2.0–5.6] versus 5.5 [3.4–6.6];p < 0.01) but had no additional effect on wound pain at rest, with movement, changing position, sitting, and walking. Intraoperative injection of 20 mg tenoxicam decreased the demand ratio for patient-controlled analgesia (PCA) and 24-hour morphine consumption by approximately 30%. ConclusionsThe data show that tenoxicam potentiates opioid analgesic effect on the somatic and visceral types of pain to different extents, and they suggest that intraoperative injection of 20 mg tenoxicam is sufficient to enhance intravenous PCA morphine on uterine cramping pain for the first 24 hours after cesarean section.

Effective Epidural Blood Patch Volumes for Postdural Puncture Headache in Taiwanese Women

BACKGROUND/PURPOSE Epidural blood patch (EDBP) is the most commonly used method to treat postdural puncture headache (PDPH). The optimal or effective blood volume for epidural injection is still controversial and under debated. This study compared the therapeutic efficacy of 7.5 mL blood vs. 15 mL blood for EDBP via epidural catheter injection. METHODS Thirty-three patients who suffered from severe PDPH due to accidental dural puncture during epidural anesthesia for cesarean section or epidural analgesia for labor pain control were randomly allocated into two groups. EDBP was conducted and autologous blood 7.5 mL or 15 mL was injected via an epidural catheter in the semi-sitting position in Group I (n = 17) and II (n = 16), respectively. For all patients in both groups, the severity of PDPH was registered on a 4-point scale (none, mild, moderate, severe) and assessed 1 hour, 24 hours and 3 days after EDBP. RESULTS There was no significant difference between the two groups of patients at all time points with respect to the severity of PDPH. Two patients in Group I and nine in Group II developed nerve root irritating pain during blood injection (p < 0.05). No systemic complications were noted in both groups of patients throughout EDBP injection. CONCLUSION We conclude that injection of 7.5 mL autologous blood into the epidural space is comparable to 15 mL blood in its analgesic effect on PDPH, but with less nerve root irritating pain during injection.

Effect of Combining Ultralow-dose Naloxone with Morphine in Intravenous Patient-controlled Analgesia: The Cut-off Ratio of Naloxone to Morphine for Antiemesis After Gynecologic Surgery

BACKGROUND/PURPOSE Admixing an ultralow dose of naloxone with intravenous morphine patient-controlled analgesia (PCA) has been shown to decrease postoperative nausea. However, the cut-off ratio of the naloxone-morphine admixture for antiemetic effects has not been investigated. The purpose of this study was to investigate the cut-off ratio of naloxone-morphine admixture in PCA for antiemesis after gynecologic surgery. METHODS This double-blind study enrolled 120 female patients who were scheduled for gynecologic surgery under general anesthesia. Patients were randomly allocated to one of three groups (n = 40 for each group). The concentration of naloxone and morphine respectively was 0 microg/mL and 1 mg/mL in group 1, 0.1 microg/mL and 1 mg/mL in group 2 (1:10,000), and 1 microg/mL and 1 mg/mL in group 3 (1:1000). Morphine consumption, verbal rating score of wound pain at rest and with exertion, and morphine-related side effects were investigated at 1, 2, 4 and 24 hours postoperatively. RESULTS A total of 112 patients completed the study (37 in group 1, 36 in group 2, 39 in group 3). The incidence of nausea during the postoperative 4-24 hours was significantly lower in group 3 than in group 1 (23.1% vs. 56.8%, p < 0.05). Furthermore, the overall incidence of severe nausea was significantly lower in group 3 than in group 1 (2.6% vs. 24.3%, p < 0.05) as was the rescue antiemetic requirements (5.1% vs. 24.3%, p < 0.05). However, there were no significant differences between groups 2 and 1. The pain scores (at rest and with exertion) and 24-hour morphine consumption were not significantly different among the three groups. CONCLUSION The antiemetic efficacy of ultralow-dose naloxone combined with PCA morphine is limited by a cut-off ratio of naloxone to morphine of 1:10,000.

Polymorphism of μ-Opioid Receptor Gene (OPRM1:c.118A>G) Might Not Protect against or Enhance Morphine-Induced Nausea or Vomiting

A cohort, double blind, and randomized study was conducted to investigate the effect of a single nucleotide polymorphism of the μ-opioid receptor at nucleotide position 118 (OPRM1:c.118A>G) on the association with the most common side effects (nausea or vomiting) induced by intravenous patient control analgesia (IVPCA) with morphine, including incidence and severity analysis. A total of 129 Taiwanese women undergoing gynecology surgery received IVPCA with pure morphine for postoperative pain relief. Blood samples were collected and sequenced with high resolution melting analysis to detect three different genotypes of OPRM1 (AA, AG, and GG). All candidates 24 h postoperatively will be interviewed to record the clinical phenotype with subjective complaints and objective observations. The genotyping after laboratory analysis showed that 56 women (43.4%) were AA, 57 (44.2%) were AG, and 16 (12.4%) were GG. The distribution of genotype did not violate Hardy-Weinberg equilibrium test. There was no significant difference neither between the severity and incidence of IVPCA morphine-induced side effects and genotype nor between the association between morphine consumption versus genotype. However, there was significant difference of the relation between morphine consumption and the severity and incidence of IVPCA morphine-induced nausea and vomiting. The genetic analysis for the severity and incidence of IVPCA morphine-induced nausea or vomiting showed no association between phenotype and genotype. It might imply that OPRM1:c.118A>G does not protect against IVPCA morphine-induced nausea or vomiting.