Comparison between conventional-dose and high-dose rocuronium use in general anesthesia for Cesarean section.

Background: There have been few studies comparing the effects of high- and low-dose rocuronium during cesarean section by directly measuring the concentration. Therefore, we conducted a study to examine the blood concentrations and clinical effects of both doses of rocuronium on mothers and fetuses. Methods: Eighteen patients were randomly assigned to two groups: C Group (0.6 mg/kg), and H Group, (1.0 mg/kg). The primary outcome was the comparison of umbilical vein rocuronium concentration between two groups. We assessed ease of intubation, time from rocuronium administration to some TOF points, post-anesthesia care unit (PACU) stay time, infused remifentanil dose, maternal rocuronium concentration, and Apgar scores. Results: No differences were observed in demographic data, ease of intubation, PACU stay time, 1 min Apgar scores, umbilical venous blood gas analysis between both groups. However, the time from rocuronium administration to T3 disappearance was shorter (p=0.009) and time to T1 and T2 reappearance were longer (p=0.003, p=0.009) in H group than that in C group. The administered remifentanil dose (p=0.042) was lower in the H group than in the C group. Rocuronium concentrations in the umbilical vein (p=0.004) and maternal vein before cord clamping (p=0.002) and at discharge (p<0.001) were also found to be higher in the H group than in the C group. Conclusions: We observed no prolongation of PACU stay, and no differences in Apgar scores in H group compared to C group. It suggests that 1.0 mg/kg of rocuronium has no negative effects on the fetus and mother in cesarean section.

Objective Assessment of Perioperative Anxiety using Functional Near-infrared Spectroscopy in Elderly Patients: A Prospective Randomized Observational Pilot Study.

Background: Assessing and managing patient anxiety is essential to reduce postoperative complications in elderly patients. However, monitoring patient anxiety objectively is impossible. This study aimed to investigate the correlation between the level of fNIRS signals and anxiety in patients aged 65 and older undergoing artificial joint replacement surgery. Material and Methods: Sixty patients aged ≥65 years scheduled for elective total knee arthroplasty under spinal anesthesia were included. To differentiate the degree of anxiety, the patients were randomly divided into three groups, each consisting of 20 patients (group 1: administered normal saline as a placebo; groups 2 and 3: administered dexmedetomidine at a rate of 0.2 and 0.5 µg/kg/h, respectively, for 10 min). Functional near-infrared spectroscopy was measured continuously for 10 min in each session (session 1: pre-anesthetic period; session 2: immediately after the spinal anesthesia period; session 3: normal saline or dexmedetomidine receiving period) in all patients. Vital signs were measured thrice at 5-min intervals during each session. State-Trait Anxiety Inventory -S (STAI-S) and Ramsay Sedation Scale (RSS) scores were assessed at the end of each session. Results: The STAI-S score was significantly correlated with power of bandwidth (p = 0.034). In addition, the RSS score was significantly correlated with BW 1, 2, and 3 (p = 0.010, p < 0.001, and p = 0.003, respectively). Conclusion: The STAI-S score and BW 3 were significantly correlated, suggesting that fNIRS might help objectively and directly monitor anxiety levels.

Impact of Nonselective and Selective α-1 Adrenergic Blockers on the Sedative Efficacy of Dexmedetomidine in Urologic Surgery: A Prospective, Observational Study.

BACKGROUND This study aimed to compare the impact of a-1 adrenergic blockers - nonselective (alfuzosin, doxazosin, and terazosin) and selective (silodosin and tamsulosin) - on the sedative effects of the alpha-2 adrenergic agonist dexmedetomidine (DMT) in patients undergoing urologic surgery. The primary outcome was the sedative effect of DMT as determined by the bispectral index (BIS) and Modified Observer's Assessment of Alertness/Sedation (MOAA/S) scale scores. MATERIAL AND METHODS One hundred eighteen patients undergoing elective urologic surgery with spinal anesthesia were recruited. Patients were assigned based on their medication status to group N (no medication; n=33), group NS (nonselective alpha-1 blocker; n=27), or group S (selective alpha-1 blocker; n=58). Mean blood pressure (MBP), heart rate (HR), oxygen saturation (SpO2), BIS, and MOAA/S scale scores were recorded at 5-minute (min) intervals after DMT administration. RESULTS Group NS had significantly higher BIS scores than groups N and S at 25 min (P=0.045) and 30 min (P=0.030) after DMT administration, indicating lower sedation levels. MBP significantly differed between the 3 groups at all time points, with group N experiencing a lower MBP than groups NS and S. No significant differences were found between the groups in MOAA/S scale scores, SpO2, or HR. CONCLUSIONS Nonselective alpha-1 adrenergic blockers can reduce the sedative effects of DMT. Consequently, there may be a need for individualized anesthesia management considering the specific subtype of alpha-1 adrenergic blocker medication.

A Study of 57 Patients with Prostate Cancer to Compare Outcomes of Estimated Blood Loss and Postoperative Pain Between Robot-Assisted Laparoscopic Radical Prostatectomy and Standard Laparoscopic Radical Prostatectomy.

BACKGROUND Robot-assisted radical prostatectomy (RARP) is becoming an increasingly common method for treatment of prostate cancer. This study aimed to compare outcomes of estimated blood loss and postoperative pain, determined by patient-controlled analgesia (PCA), between RARP and standard laparoscopic radical -prostatectomy (LRP). MATERIAL AND METHODS We enrolled 57 patients who had localized prostate cancer (28 patients in RARP, 29 patients in LRP). Primary outcomes were estimated blood loss (EBL) measured by gravimetric method for gauze and visual estimation for suction bottle, and PCA bolus count that the bolus doses were injected at the 1st, the 6th, the 24th, and the 48th hour after the operation. We recorded anesthesia and operation time, pneumoperitoneum duration, vital signs, fluid volume, and remifentanil use. Using the numeric rating scale (NRS), adverse effects were checked at the 1st, the 6th, the 24th, and the 48th hour and patient satisfaction was assessed at the 48th hour after the operation. RESULTS Anesthesia time, operation time, and gas insufflation time were longer (P=0.001, P=0.003, P=0.021), and patient-controlled analgesia (PCA) bolus counts at the 1st hour after the operation and volumes of administered crystalloid and remifentanil were higher in the RARP group than in the LRP group (P=0.013, P=0.011, P=0.031). There were no significant differences in EBL. CONCLUSIONS The RARP group required longer anesthetic time and more analgesics during the acute postoperative period compared to the LRP group. Regarding anesthesia, LRP is as good a surgical procedure as RARP until the operation time and the number of ports are reduced.

The EZ-Blocker® for one-lung ventilation in a patient with Kartagener syndrome and tracheal bronchus -a case report.

BACKGROUND: The tracheal bronchus in Kartagener syndrome is a rare case that may cause difficulty in one-lung ventilation (OLV). Here we reported a case of successful OLV using bronchial blocker in a patient with tracheal bronchus and Kartagener syndrome (KS). CASE: A 66-year-old female patient with Kartagener syndrome was admitted for left-side diaphragmatic plication. The patient's preoperative computed tomography image showed a tracheal bronchus of the apical segment in the right upper lobe. The patient received epidural analgesia and general anesthesia through total intravenous anesthesia. An EZ-Blocker® (Teleflex Life Sciences Ltd., Ireland) was used to perform OLV. CONCLUSIONS: OLV through an EZ-Blocker® can be successfully performed in tracheal bronchus patients with Kartagener syndrome without side effects.

Paradoxical carbon dioxide embolism during laparoscopic hepatectomy without intracardiac shunt: A case report.

BACKGROUND: Laparoscopic hepatectomy has recently become popular because it results in less bleeding than open hepatectomy. However, CO2 embolism occurs more frequently. Most CO2 embolisms during laparoscopic surgery are self-resolving and non-symptomatic; however, severe CO2 embolism may cause hypotension, cyanosis, arrhythmia, and cardiovascular collapse. In particular, paradoxical CO2 embolisms are highly likely to cause neurological deficits. We report a case of paradoxical CO2 embolism found on transesophageal echocardiography (TEE) during laparoscopic hepatectomy, although the patient had no intracardiac shunt. CASE SUMMARY: A 71-year-old man was admitted for laparoscopic left hemihepatectomy. During left hepatic vein ligation, the inferior vena cava was accidentally torn. We observed a sudden drop in oxygen saturation to 85%, decrease in systolic blood pressure (SBP) below 90 mmHg, and reduction in end-tidal CO2 to 24 mmHg. A "mill-wheel" murmur was auscultated over the precordium. The fraction of inspired oxygen was increased to 100% with 5 cmH2O of positive end-expiratory pressure (PEEP) and hyperventilation was maintained. Norepinephrine infusion was increased to maintain SBP above 90 mmHg. A TEE probe was inserted, revealing gas bubbles in the right side of the heart, left atrium, left ventricle, and ascending aorta. The surgeon reduced the pneumoperitoneum pressure from 17 to 14 mmHg and repaired the damaged vessel laparoscopically. Thereafter, the patient's hemodynamic status stabilized. The patient was transferred to the intensive care unit, recovering well without complications. CONCLUSION: TEE monitoring is important to quickly determine the presence and extent of embolism in patients undergoing laparoscopic hepatectomy.

Comparison of efficacy between palonosetron-midazolam combination and palonosetron alone for prevention of postoperative nausea and vomiting in patients undergoing breast surgery and patient controlled analgesia: A prospective, randomized, double-blind study: A CONSORT-compliant study.

BACKGROUND: Postoperative nausea and vomiting (PONV) is a common complaint in patients following general anesthesia. Various antiemetics, including 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, are effective but still have limited efficacy. Therefore, combination therapy is preferable to using a single drug alone in high-risk patients. We performed a comparative study on the antiemetic effect of palonosetron, a 5-HT3 receptor antagonist, monotherapy vs palonosetron-midazolam combination therapy for the prevention of PONV. METHODS: A total of 104 female patients scheduled for breast cancer surgery were enrolled. They were randomly divided into 2 groups, a palonosetron monotherapy group (group P) and palonosetron-midazolam combination therapy group (group PM). Both groups received 0.075 mg palonosetron intravenously after induction of anesthesia. Patient-controlled analgesia (PCA) was applied according to the allocated group. Intravenous (IV)-PCA in group P consisted of fentanyl 20 µg/kg plus normal saline (total volume: 100 ml); IV-PCA in group PM consisted of fentanyl 20 µg/kg plus midazolam 4 mg plus normal saline (total volume: 100 ml). Efficacy parameters were collected during 0 to 1, 1 to 6, 6 to 24, and 24 to 48 hours postoperative time intervals. These measures included complete response (defined as no PONV and no rescue anti-emetic use) rate, incidence of PONV, sedation score, rescue antiemetic use, rescue analgesic use, and numerical rating scale (NRS) for pain. The complete response rate during the 0 to 24 hours interval was analyzed as the primary outcome. RESULTS: Although the complete response rate between 0 and 24 hours was higher in group PM (42.3% and 48.1% in group P and PM, respectively), there was no statistically significant difference (P = .55). The complete response rates in other time intervals were not different between the 2 groups as well. The sedation score and NRS score also showed no differences between the 2 groups. CONCLUSIONS: The combination therapy of palonosetron with midazolam did not lead to a greater reduction in the incidence of PONV than monotherapy in patients undergoing breast surgery and receiving IV-PCA containing fentanyl.

Usefulness of using additional ultrasonic dissection device in breast cancer surgery: a retrospective cohort study.

BACKGROUND: In breast cancer surgery, electrocautery (EC) is commonly used with the basic method of knot tying, and there are few reports of using other devices such as ultrasonic dissection device (UDD). This study was designed to compare the case of using EC with the basic method of knot tying and the case of using UDD in breast cancer surgery. METHODS: From April 2019 to March 2020, 376 patients who underwent breast cancer surgery at Pusan National University Hospital were enrolled. We compared operation time, complications, and blood loss volume between surgery with and without UDD. RESULTS: We included 306 patients for the final analysis, 142 in the control group and 164 in the trial group. The operation time [minutes (min)] was significantly reduced in the trial group compared to the control group (111.2 vs. 95.5 min, P<0.001). In subgroup analysis, the operation time in the trial group was significantly reduced. There was no significant difference in intraoperative blood loss (P=0.999) and complications [seroma (P=0.965), hematoma (P=0.999), cellulitis (P=0.999)]. CONCLUSIONS: Our study showed that the use of a UDD for surgeons to select instruments for breast cancer surgery may be a good option for both patients and surgeons.

Evaluation of Analytical Performances of Magnetic Force-Assisted Electrochemical Sandwich Immunoassay for the Quantification of Carcinoembryonic Antigen.

Carcinoembryonic antigen (CEA) is a biomarker indicated in different cancers, targeted for quantitative analysis via immunoassay. Here we introduce a new technique called magnetic force-assisted electrochemical sandwich immunoassay (MESIA) for determination of CEA level in a drop of human serum using a fully automated point-of-care testing (POCT) device. The analytical performances of the assay are assessed based on precision, accuracy, limit of blank (LoB), limit of detection (LoD) and limit of quantitation (LoQ), linearity, Hook effect, interference, cross-reactivity, and method comparison following the guidelines of the Clinical Laboratory Standards Institute (CLSI). The LoD is 0.50 ng/ml. A linear relationship is shown in the range of 0.5-200 ng/ml. A high dose effect is not seen up to approximately 500,000 ng/ml. The recovery range is from 94.7 to 108.9%. The %CV of run-to-run and within-lab variations are less than 2.04 and 4.41% across the CEA concentrations, respectively, whereas reproducibility is 4.45-6.24%. Method comparison shows that the assay correlates well with the reference device (R 2 = 0.9884). The assay demonstrates acceptable precision, accuracy, LoB, LoD and LoQ, hook effect, linearity, interference, cross-reactivity, and high correlation with its reference device. Thus, the system is suitable for the quantification of CEA in clinical practices with a POCT manner.

The analgesic efficacy of a single injection of ultrasound-guided retrolaminar paravertebral block for breast surgery: a prospective, randomized, double-blinded study.

BACKGROUND: The thoracic paravertebral block is an effective analgesic technique for postoperative pain management after breast surgery. The ultrasound-guided retrolaminar block (RLB) is a safer alternative to conventional paravertebral block. Thus, we assessed the analgesic efficacy of ultrasound-guided RLB for postoperative pain management after breast surgery. METHODS: Patients requiring breast surgery were randomly allocated to group C (retrolaminar injection with saline) and group R (RLB with local anesthetic mixture). The RLB was performed at the level of T3 with local anesthetic mixture (0.75% ropivacaine 20 mL + 2% lidocaine 10 mL) under general anesthesia before the skin incision. The primary outcome was cumulative morphine consumption using intravenous patient-controlled analgesia (IV-PCA) at 24 hour postoperatively. The secondary outcomes were the visual analogue scale (VAS) scores at 1, 6, 24, and 48 hour postoperatively and the occurrence of adverse events and patient satisfaction after the surgery. RESULTS: Forty-six patients were included, 24 in group C and 22 in group R. The cumulative morphine consumption using IV-PCA did not differ between the two groups (P = 0.631). The intraoperative use of remifentanil was higher in group C than in group R (P = 0.025). The resting and coughing VAS scores at 1 hour postoperatively were higher in group R than in group C (P = 0.011, P = 0.004). The incidence of adverse events and patient satisfaction was not significantly different between the two groups. CONCLUSIONS: A single injection of ultrasound-guided RLB did not reduce postoperative analgesic requirements following breast surgery.

Randomized controlled trial assessing the effectiveness of midazolam premedication as an anxiolytic, analgesic, sedative, and hemodynamic stabilizer.

BACKGROUND: Midazolam premedication is widely used before general anesthesia, but lacks clinical evidence of effectiveness. The present study aimed to evaluate the effectiveness of midazolam premedication following 4 aspects: anxiety reduction, sedation, hemodynamic stabilization, and analgesia. METHODS: In a randomized, single-blind, prospective study, a total of 128 women were allocated to the midazolam premedication group (Group P, n = 64) or the control group (Group N, n = 64). The patients were asked to complete the Beck anxiety inventory (BAI) 2 times: on the day before surgery (BS) and 30 minutes after midazolam premedication (T0). Depth of anesthesia using state entropy (SE), conventional hemodynamic data using heart rate (HR) and mean blood pressure (MBP), and analgesic profiles using surgical pleth index (SPI) were acquired at the following 4 points: T1-pre-induction, T2-prior to intubation, T3-intubation, and T4-20 minutes after intubation. RESULTS: No change in BAI score was observed between BS and T0 in both groups P and N (median and interquartile range [IQR], Group P: BS-4.5 [2.0-7.0], T0-4.0 [1.0-9.0], P = .603; Group N: BS-4.0 [1.0-8.5], T0-3.5 [1.0-6.0], P = .066). Midazolam premedication reduced SE at T2-4 (mean difference with 95% confidence interval [95% CI], T2-7.1 [1.6-12.6], P = .012; T3-10.4 [6.5-14.4], P < .001; T4-9.2 [5.0-13.4], P < .001). Midazolam premedication also reduced HR (mean differences [95% CI], T1-7.3 [2.5-12.1], P = .003; T3-6.6 [1.1-12.2], P = .020) and MBP at T1 and T3 (mean differences [95% CI], T1-7.3 [2.5-12.1], P = .003; T3-8.6 [1.3-15.9], P = .021), and lowered SPI at T1-3 (mean differences [95% CI]: T1-12.7 [6.1-19.4], P < .001; T2-6.0 [0.5-11.5], P = .033; T3-7.9 [1.7-14.1], P = .012). CONCLUSION: Midazolam premedication did not reduce the level of anxiety. However, midazolam premedication reduced the entropy values, stabilized hemodynamics, and provided analgesia during the induction of anesthesia. The purpose of midazolam premedication needs to be reconsidered.

Comparison of patient-controlled epidural analgesia with patient-controlled intravenous analgesia for laparoscopic radical prostatectomy.

BACKGROUND: Patient-controlled epidural analgesia (PCEA) is known to provide good postoperative analgesia in many types of surgery including laparoscopic surgery. However, no study has compared PCEA with patient-controlled intravascular analgesia (PCIA) in laparoscopic radical prostatectomy (LARP). In this study, the efficacy and side effects of PCEA and PCIA after LARP were compared. METHODS: Forty patients undergoing LARP were randomly divided into two groups: 1) a PCEA group, treated with 0.2% ropivacaine 3 ml and 0.1 mg morphine in the bolus; and 2) a PCIA group, treated with oxycodone 1 mg and nefopam 1 mg in the bolus. After the operation, a blinded observer assessed estimated blood loss (EBL), added a dose of rocuronium, performed transfusion, and added analgesics. The numeric rating scale (NRS), infused PCA dose, and side effects were assessed at 1, 6, 24, and 48 h. RESULTS: EBL, added rocuronium, and added analgesics in the PCEA group were less than those in the PCIA group. There were no significant differences in side-effects after the operation between the two groups. Patients were more satisfied with PCEA than with PCIA. The NRS and accumulated PCA count were lower in PCEA group. CONCLUSIONS: Combined thoracic epidural anesthesia could induce less blood loss during operations. PCEA showed better postoperative analgesia and greater patient satisfaction than PCIA. Thus, PCEA may be a more useful analgesic method than PICA after LARP.

Anesthetic experience of frontotemporal dementia patient with severe autonomic dysfunction: a case report.

Anesthetic experience in frontotemporal dementia (FTD) with severe hypotension associated autonomic dysfunction has not yet been reported. Here in case, we report on the case of treatment with vasopressin to refractory hypotension in FTD patient. A 54-year-old male presented with a ten-year history of FTD with frequent syncope. The patient was scheduled to undergo subtotal gastrectomy for resection of stomach cancer. During the operation, sudden hypotension occurred and it was refractory to fluid and 1 unit of blood resuscitation and did not respond to catecholamine. Transesophageal echocardiography showed normal heart with adequate volume state. After intravenous administration of arginine vasopressin, the patient's vital signs returned to baseline values. Arginine vasopressin might be considered as a valuable alternative for treatment of severe refractory hypotension in autonomic dysfunction patients with FTD.

A Randomized Clinical Trial of Nefopam versus Ketorolac Combined With Oxycodone in Patient-Controlled Analgesia after Gynecologic Surgery.

OBJECTIVES: Nefopam is a centrally-acting non-opioid analgesic, which has no effect on bleeding time and platelet aggregation. There has been no study about nefopam and oxycodone combination for postoperative analgesia. In this study, we present efficacy and side effects of nefopam/oxycodone compared with ketorolac/oxycodone in patient-controlled analgesia (PCA) after gynecologic surgery. METHODS: 120 patients undergoing gynecologic surgery were divided randomly into two groups: Nefopam group treated with oxycodone 1 mg and nefopam 1 mg bolus; and Ketorolac group treated with oxycodone 1 mg and ketorolac 1.5 mg bolus. After the operation, a blinded observer assessed the pain with a numeric rating scale (NRS), infused PCA dose and sedation score at 1, 4, 24, and 48 h, nausea, vomiting, headache, shivering, pruritus and delirium at 6, 24 and 48 h, and satisfaction at 48 h after the operation. RESULTS: Nefopam group showed less nausea than Ketorolac group within 6 h after the operation. There were no significant differences in demographic data and other complications between both groups. At 48 h after operation, satisfaction and the infused PCA volumes of Nefopam group (34.0± 19.7 ml) showed no significant differences compared to Ketorolac group (30.7± 18.4 ml, P-value= 0.46). CONCLUSION: Nefopam showed a similar efficacy and lower incidence of nausea within 6 h after the operation to that of ketorolac in PCA. Nefopam may be a useful analgesic drug for the opioid-based PCA after gynecologic surgery. Further evaluation of accurate equivalent dose of nefopam as well as pharmacokinetics of bolus administration is required.

Modeling of safe window for percutaneous thoracic sympathectomy.

PURPOSE: Despite the many benefits of percutaneous thoracic sympathectomy, it also has serious complications such as pneumothorax. This study was conducted in order to determine the safe percutaneous entering window and angles for the needle during T2 and T3 thoracic sympathectomy avoiding pneumothorax. METHODS: Transverse section of CT images that crosses at the middle of the T2 or T3 vertebral body was selected. Medial and lateral imaginary lines were drawn from the dorsoventrally midpoint on the lateral surface of the vertebral body (v) to the skin. The medial one was drawn to the skin medially as much as possible tangent to the vertebral body (vM). The lateral one was drawn to the skin tangent to parietal pleura (vL). c was defined as the point where the midsagittal line meets the skin. The distance cM and cL, the angle aM and aL made between the midsagittal line and vM or vL lines were measured. To determine the relations between patients' covariates and measured data, mixed-effect population analysis was performed for the cL, aL, and vL. RESULTS: In males, the mean values of cL were 85.3 and 79.2 mm for T2 and T3, respectively. In females, they were 71.5 and 63.7 mm for T2 and T3, respectively. Population analysis revealed that cL was best described with age, weight, gender covariates, and interindividual variability. The aL was best described with BMI and gender covariates. CONCLUSIONS: The covariates' relationship and interindividual variability resulting from the mixed-effect analysis enhanced individual prediction for safe widows.

Hemorrhagic shock occurring due to a concealed hematoma after insertion of a subclavian venous catheter in a patient undergoing anticoagulation therapy: a case report.

A 74-year-old man who had been receiving warfarin for atrial fibrillation, underwent emergency thrombectomy. A central venous catheter (CVC) was inserted via the left subclavian vein, and heparin was administered to prevent preoperative and postoperative thrombotic events. After an uneventful thrombectomy, the patient was transferred to the intensive care unit (ICU). On the second postoperative day, the patient developed syncope and his blood pressure and oxygen saturation decreased. A computed tomography (CT) revealed a huge hematoma under the pectoralis major muscle. The patient was then treated with continuous renal replacement therapy and mechanical ventilation for multiorgan dysfunction syndrome, which developed due to hemorrhagic shock in the ICU. These findings suggest that when a CVC is inserted in patients requiring anticoagulant therapy, the possible risk of excessive bleeding must be carefully considered. Further, choosing a proper insertion site and performing an ultrasound-guided aspiration may be helpful in preventing these complications.

Oxycodone vs. fentanyl patient-controlled analgesia after laparoscopic cholecystectomy.

OBJECTIVES: Oxycodone is semi-synthetic opioid, oral and parenteral preparations have been widely used for acute and chronic pain. The aim of this study was to assess the efficacy and side effects of oxycodone and fentanyl in patient controlled analgesia (PCA) after laparoscopic cholecystectomy. METHODS: A prospective, randomized, double-blind study was conducted. 81 patients were randomly divided into two groups; fentanyl (10 mcg fentanyl and 1.5 mg ketorolac) and oxycodone group (1 mg oxycodone and 1.5 mg ketorolac). After the operation, a blinded observer assessed pain using a numerical rating scale (NRS), infused PCA dose, side effects, sedation levels, and satisfaction. RESULTS: Cumulative PCA dose of oxycodone group at 48 h (31.4 ± 16.0 ml) was significantly less than that of fentanyl group (43.8 ± 23.1 ml, P = 0.009). Oxycodone group showed more nausea at 6-24 h after the operation (P = 0.001), but there was no difference in satisfaction score (P = 0.073). There were no significant differences in other side effects, sedation and NRS scores between two groups. CONCLUSION: Oxycodone showed comparable effects for pain relief compared to fentanyl in spite of less cumulative PCA dose. Based on these results, we could conclude that oxycodone may be useful as an alternative to fentanyl for PCA after laparoscopic cholecystectomy.

Gender differences in paclitaxel-induced neuropathic pain behavior and analgesic response in rats.

BACKGROUND: Females show greater sensitivity than males to several modalities of experimental pain. However, the gender differences in paclitaxel-induced neuropathic pain have not been studied. The current study examined the gender differences in neuropathic pain behavior and the effect of analgesics in a paclitaxel-induced neuropathic pain model in rats. METHODS: Neuropathic pain was induced by intraperitoneal injection of paclitaxel (2 mg/kg) on 4 alternate days in Sprague-Dawley rats of both genders. Mechanical allodynia was measured using a von Frey filament. The gender differences in analgesic responses were determined after administration of morphine (2 or 5 mg/kg), ketamine (2 or 5 mg/kg), or combined morphine (2 mg/kg) and ketamine (2 mg/kg). RESULTS: Paclitaxel induced mechanical allodynia, which began to manifest on day 4, peaked within 10 days, and plateaued for at least 2 months after the first paclitaxel injection. No gender difference in the manifestation of mechanical allodynia was observed. A 2 mg/kg dose of ketamine increased the mechanical threshold only in males. The 5 mg/kg dose of ketamine significantly increased the mechanical threshold in both genders. Morphine (2 and 5 mg/kg) dose-dependently increased the mechanical thresholds in both genders. The 2 mg/kg dose of ketamine enhanced the antinociceptive effect of 2 mg/kg morphine only in females. CONCLUSIONS: No gender difference in paclitaxel-induced neuropathic pain or analgesic response to ketamine or morphine was observed in Sprague-Dawley rats. Low dose ketamine enhanced the analgesic effect of morphine on paclitaxel-induced mechanical allodynia but only in female rats.