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Background Neuromodulation therapies offer a treatment option that has minimal side effects and is relatively safe and potentially reversible. Spinal cord stimulation (SCS) has been used to treat various pain conditions for many decades. High-frequency SCS (HFSCS) involves the application of a single waveform at 10,000 Hz at a subthreshold level, therefore providing pain relief without any paresthesia. Methods We tested whether early HFSCS treatment attenuated spared nerve injury (SNI)-induced neuropathic pain. The phosphorylation profile of mitogen-activated protein kinases (MAPKs), i.e., extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinases (JNKs), and p38, was evaluated to elucidate the potential underlying mechanism. Results SNI of rat unilateral sciatic nerves induced mechanical hyperalgesia in the ipsilateral hind paws. Rats were assigned to SCS sessions with HFSCS (frequency 10 kHz; pulse width 30 μs; pulse shape of charge-balanced, current controlled; delivered continuously for 72 h), or sham stimulation immediately after SNI. Tissue samples were examined at 1, 3, 7, and 14 days after SNI. Behavioral studies showed that HFSCS applied to the T10/T11 spinal cord significantly attenuated SNI-induced mechanical hyperalgesia compared with the sham stimulation group. Moreover, western blotting revealed a significant attenuation of the activation of ERK1, ERK2, JNK1, and p38 in the dorsal root ganglia and the spinal dorsal horn. Conclusion Application of HFSCS provides an effective treatment for SNI-induced persistent mechanical hyperalgesia by attenuating ERK, JNK, and p38 activation in the dorsal root ganglia and the spinal dorsal horn.

Background and Goal of StudytIntubation difficulty is an important issue in daily clinical practice for anesthesiologists.1 Intubation difficulty scale (IDS) was introduced in 1997 to capture 7 major factors comprehensively,2 but there has been no estimation on relative impacts of time for each one of them. Otherwise, predict power of IDS has been questioned on video tracheal intubation system.3 This study aims to quantify the time required to tackle every factor. Materials and MethodsAfter approval from the IRB (institutional review board), we collected written informed consent from each patient (CYCH IRB: 097028). Preoperatively, a complete medical history related to tracheal intubation (TI) was obtained from every adult patient that would receive an operation and TI under direct laryngoscopy with a #3 Macintosh blade. After induction, the anesthetists recorded the direct view score according to the 7 IDS factors.. With a stop watch, a research assistant independently recorded the duration of each attempt until a successful intubation. We construct multiple linear regression and mixed effects models to determine the relative time impact of each factor.ResultsA total of 1095 patients were collected. The IDS score ranged from 0 to 10. There were 37.1% and 1.8% of them with IDS=0 and >5, respectively, which were lower than those reported by Adnet,2 or, 5.3%. (Figure 1) The mean duration of intubation was 23.9u00b121.8 seconds. The final linear regression equation was as follows: Duration of intubation time in seconds = 15.2 + 31.1 (no. additional attempts) + 26.2 (no. additional operators) + 11.4 (no. alternative techniques) + 7.9 (intubation with increased lift force) + 4.9 (intubation with external laryngeal pressure) + 3.5 (Cormack grade - 1). (Table 1) After adjustment for repeated intubations by the same anesthesiologists with mixed effects model, we found the regression coefficients were largely the same, indicating the robustness of this model. ConclusionAll factors included in the IDS contribute to the time required for intubation except vocal cord adduction. After more corroboration in different settings, the equation would be useful to predict the required time as a feedback on training sessions of tracheal intubation.

Hemorrhoidectomy usually leads to severe postoperative pain that often causes urinary retention. Topical EMLA cream (lidocaine 2.5% and prilocaine 2.5%) has been used extensively in the clinical setting. This prospective study tested the effectiveness of EMLA cream for postoperative pain control after hemorrhoidectomy.Thirty patients admitted for hemorrhoidectomy were enrolled and randomly assigned into either a control group (n = 15) or EMLA group (n = 15). Postoperatively, the control group received approximately 5 g of neomycin ointment, and the EMLA group received approximately 5 g of EMLA. A visual analog scale (VAS) score was recorded on arrival in the postanesthesia recovery unit (PAR), after 2 hours in the PAR, on the first postoperative evening, and on the first postoperative morning. The requested frequency and dosage of meperidine, the first spontaneous voiding time, the frequency of single urinary catheterization, and a patient satisfaction score were also obtained.The VAS score and frequency and dosage of meperidine injections were significantly lower in the EMLA group than in the control group (P.01). The voiding time was significantly later in the control group (P = .04). The frequency of single catheterization was significantly lower in the EMLA group than in the control group (P = .03). Patient satisfaction with postoperative pain control was significantly higher in the EMLA group than in the control group (P.01). No systemic complications were observed.Topical EMLA cream decreased pain intensity and meperidine requests, reduced the frequency of single catheterizations, and improved patient satisfaction with postoperative pain management after hemorrhoidectomy in adults.

For optimal use of antinociceptive gene therapy, it may be important to have extrinsic control of the expression of the transfected gene. To achieve this goal, we used a tetracycline-inducible system (Tet-On) composed of three plasmids coding for beta-endorphin, the tetracycline transcriptional activator rtTA, and the silencer tTS. The regulation of beta-endorphin expression was first assessed in cultures of dorsal root ganglion neurons. The three plasmids were then electrotransfected into the spinal cord of mononeuropathic rats and the analgesic potential of this therapy in vivo was evaluated by thermal-withdrawal latency and the mechanical-withdrawal threshold. Intraperitoneal injections of doxycycline were made to evaluate the possibility of exogenous upregulation of transfected beta-endorphin gene expression in vivo. The levels of beta-endorphin were analyzed by intrathecal microdialysis and radioimmunoassay. We found that, after doxycycline administration, the expression of beta-endorphin was rapid, stable, and tightly regulated (low background and high induction level) both in vitro and in vivo. The beta-endorphin protein was secreted into cerebrospinal fluid at a peak level of 53 pmol/L in dialysate, which was sufficient to inhibit neuropathic pain. In conclusion, tightly controlled expression of beta-endorphin can be obtained following intrathecal electrotransfer of a tetracycline-inducible, three-plasmid-based system, and doxycycline-dependent beta-endorphin protein expression in this system alleviates sciatic nerve constriction-induced limb pain.

To determine whether a combination of topical anesthetic (EMLA) and local injection with lidocaine is better than lidocaine alone for pain relief after Ferguson hemorrhoidectomy.Sixty patients scheduled for hemorrhoidectomy were randomized into 2 groups: (1) control group (CG, n=30) received neomycin ointment (5 g), and (2) EMLA group (EG, n=30) received EMLA (5 g), both agents applied topically after surgery. Before the surgical incision was made, lidocaine (10 mL of a 1% solution) was locally injected into all 60 patients. After surgery, analgesics were provided when necessary. The visual analog scale score was recorded at 4 time points: (1) upon arrival in the postanesthesia room, (2) 2 hours after arriving in the postanesthesia room, (3) between 9 and 10 PM on the first postoperative evening, and (4) on the first postoperative morning. The frequency of meperidine requests, 1-time catheterizations for urinary retention, and patient satisfaction with postoperative pain management, were also recorded.The median visual analog scale scores and cumulative dosages of meperidine were significantly lower in the EG than the CG (P0.05). Patient satisfaction with postoperative pain control was also significantly higher in the EG than the CG (P0.01). No systemic complications occurred.EMLA is considered a breakthrough in cutaneous analgesia, capable of reducing pain in many cutaneous procedures. Because Ferguson hemorrhoidectomy has been performed for years with ongoing concerns over postoperative pain, we felt that using EMLA could lower postoperative pain intensity and the number of requests for additional medication.

Background: Animal and human studies indicate that genetics may contribute to the variability of morphine efficacy. A recent report suggested that cancer patients homozygous for the 118G allele caused by the single nucleotide polymorphism at nucleotide position 118 in the -opioid receptor gene require higher doses of morphine to relieve pain. The purpose of the current study was to investigate whether this polymorphism contributes to the variability of morphine efficacy in women who undergo abdominal total hysterectomy. Methods: After informed consent was obtained, 80 female patients (American Society of Anesthesiologist physical status I or II) scheduled to undergo elective total hysterectomy surgery were enrolled in this study. All patients received general anesthesia and were screened for A118G polymorphism by blood sample. Intravenous morphine patient-controlled analgesia was provided postoperatively for satisfactory analgesia. The authors recorded the morphine consumption doses and demand times. Pain at rest and side effects were measured with rating scales. Results: Forty-three women were A118 homozygous, 19 were heterozygous, and 18 were G118 homozygous. Patients homozygous for G118 required more morphine doses (33 10 mg) to achieve adequate pain relief compared with patients homozygous for A118 (27 10 mg) in the first 24 h (P 0.02). However, there was no statistically significant difference for morphine consumption at 48 h. Conclusion: Genetic variation of the -opioid receptor may contribute to interindividual differences in postoperative morphine consumption. In the future, identifying single nucleotide polymorphisms of patients may provide information to modulate the analgesic dosage of opioid for better pain control. IT has been known for a long time that the effects of morphine as an agent for pain control vary in different individuals. Morphine produces its clinical effects mainly through -opioid receptors. Polymorphisms in the -opioid receptor gene may be associated with the clinical effects of opioid analgesics, 1–3 which encourages research into human genetic polymorphisms and their clinical consequences. Several single nucleotide polymorphisms (SNPs) have been identified in the human -opioid receptor gene. The A118G mutation is the most common one leading to a change in the gene product in the human -opioid receptors, which is an A to G substitution in exon 1 and results in an amino acid exchange at position 40 from asparagine to aspartate (N40D). 4 Functional effects of the A118G polymorphism have been demonstrated both in vitro and in vivo. In vitro, -endorphin has been shown to bind three times more tightly at the receptor of homozygous G allele than at that of homozygous A allele. 4 A recent report also suggested that cancer patients who were homozygous for the G118 variant required higher doses of oral morphine for long-term treatment of their pain. 2 Romberg et al. 5,6 studied the pharmacokinetics and pharmacodynamics of morphine-6-glucuronide (M6G), a -opioid agonist, and also found that A118G mutation of the human -opioid receptor gene reduced analgesic responses to M6G. The effect of -opioid receptor genotype on acute postoperative morphine requirements has not been reported; therefore, we decided to determine morphine consumption with intravenous patient-controlled analgesia in women undergoing total abdominal hysterectomy according to A118G polymorphism.

Background Brain damage is a serious complication of cardiac anesthesia. The purpose of this study was to detect brain damage at different surgical stages during coronary artery bypass graft with or without cardiopulmonary bypass. Methods We conducted a prospective, longitudinal study to evaluate serum S-100 β protein, an early marker of brain injury, in patients electively undergoing off-pump (n = 30) or traditional coronary artery bypass graft (n = 60). Blood was sampled immediately before anesthesia, before and after cardiopulmonary bypass, and on the day after surgery. Results Serum S-100 β protein was lowest immediately before induction of anesthesia and significantly increased before and after cardiopulmonary bypass, then declined by the first postoperative day in both groups. Peak values were highest in the traditional group directly after coronary artery bypass graft. On the day after surgery, S-100 β protein levels were similar between groups, but were higher than baseline within each group. Significant increase in serum S-100 β protein was also observed even before cardiopulmonary bypass in cardiopulmonary bypass patients, or before manipulation of the heart and aorta in off-pump patients. These reflect the possibility that brain damage may occur before major manipulation (cardiopulmonary bypass or manipulating heart and aorta). Moreover, S-100 β levels did not return to normal on the day after the operation. Conclusions This prospective study has shown that serum S-100 β protein was not only higher than baseline both after cardiopulmonary bypass and on the day after surgery in both groups of patients but it was also significantly increased before cardiopulmonary bypass or manipulation of the heart or aorta. These findings may have implications for anesthesiologic care during the total course of cardiac surgery.

Background: The aim of the study was to compare the recovery profile of epidural and general anesthesia for hemorrhoidectomy. Methods and patients: Anesthesia and post-anesthetic recovery records of sixty patients undergoing hemorrhoidectomy were reviewed retrospectively. Thirty patients received general anesthesia (group I) and 30 epidural anesthesia (group II). The procedure time, discharge time from the post anesthetic care unit (PACU), demerol required for pain relief in PACU and 24 hours in the ward were recorded and compared using the Kruskal–Wallis test. The incidence of urinary retention, nausea and vomiting were also recorded. Results: There was no different in the age, weight and the operating time between groups. In PACU, 80% of the patients from group I suffered form postoperative pain requiring 22.8 ± 16.9 mg demerol for pain relief, while no patients from group II complained of pain and were discharged to ward significantly earlier. In the ward, the number of patients suffering from...

Background: Epidural anesthesia is widely used in the obstetric setting for providing not only labor pain relief, but also surgical analgesia for cesarean section and postoperative pain relief. However, the side effect of pruritus is of great concern for its high occurrence rate. The aim of our study was to compare and analyze the effectiveness of different regimens of epidural morphine analgesia for postcesarean section patients experiencing pruritus. Methods: We had retrospectively studied from June 2003 to April 2004 144 subjects undergoing cesarean section who agreed to accept postoperative pain relief via epidural route. Visual analogue scales (VAS) were compared between subjects not experiencing pruritus (Group I) and subjects experiencing pruritus (Group II) with modified regimens. Results: Thirty six subjects (Group II) out of 144 patients (25%) suffered from pruritus. Six different regimens were prescribed by anesthesiologists in these subjects. The characteristic of most different regim...

Background The purpose of the study was to compare the intraoperative blood glucose changes and the dosage of glucose infused between biliary atresia and glycogen storage disease (GSD) patients undergoing living donor liver transplantation (LDLT). Patients and methods The anesthesia records of biliary atresia and GSD patients undergoing LDLT were reviewed retrospectively. The levels of intraoperative blood glucose before operation, after induction of anesthesia, in the dissection, anhepatic, 10 min after reperfusion, and at the end of operation, as well as the dosage glucose infused, were compared between groups. The Mann-Whitney U test was used for statistical analysis; P Results Seventy-two biliary atresia patients were grouped into group I (GI) and 8 GSD patients into group II (GII). The blood glucose levels of both groups increased after operation and remained hyperglycemic, around 100–300 mg/dl, until the end of the operation. The mean glucose amounts infused were 2.7 ± 1.9 and 2.5 ± 1.15 mg/kg/min for GI and GII, respectively. Conclusion No significant difference was found in the anesthetic management between groups. The only difference was that the GSD patients required continuous glucose supply the night before the operation, while biliary atresia patients did not.

In this case report, we describe a 70-year-old male patient who sustained Kounis syndrome induced by cisatracurium administration immediately following induction of general anesthesia. Acute coronary syndrome combined with anaphylactic shock, termed Kounis syndrome, should be investigated in percutaneous coronary intervention to solve this complex and life-threatening condition. A team effort by cardiologist and anesthesiologist is essential for successful resuscitation. In general, the incidence of an anaphylactic reaction to cisatracurium is low, but a high serum IgE level in combination with a positive skin prick test in our patient was strongly suggestive of cisatracurium-induced Kounis syndrome. In addition, a cross-reaction be tween cisatracurium and rocuronium is reported.

Video-assisted thoracoscopic surgery (VATS) has been performed during ganglionectomy and bullectomy and usually requires a collapsed or immobilized lung. Transtracheal insufflation of oxygen (TRIO) maintains an immobilized lung, adequate oxygenation, and partial CO2 elimination but has never been used for VATS. We have simplified the TRIO design with a catheter inserted through the lumen of the orotracheal tube in what we call "transorotracheal tube TRIO" (TRIO-TOTT) and investigated its clinical use on simple VATS. Eleven patients undergoing bullectomy for primary simple pneumothorax (PSP) were studied. During the performance of VATS, a 12-gauge suction catheter was inserted as our modification and connected to the gas outlet of an anesthetic machine. The flow rate of oxygen was maintained at 10 L/min. Blood gas was collected prior to TRIO-TOTT, during TRIO-TOTT at 5, 10, 15, and 20 min, and 5 min after TRIO-TOTT. The blood gas data showed excellent oxygenation while the PaCO2 increased at a rate of 1.2 mm Hg/min compared to 3-4 mm Hg/min for apnea oxygenation. After 20 min, the mean +/- SEM PaO2 and PaCO2 were 428 +/- 27 and 65.0 +/- 2.6 mm Hg, respectively. We conclude that TRIO-TOTT is a simple, safe, and effective ventilation method for simple VATS.

The effect of acupuncture at life-saving point on the central nervous depressive action of anesthetics was investigated in rabbits. Stimulation with electroacupuncture (EA) inserted in Jen-Chung point, which is located at the mid-point on the upper lip, decreased the sleeping time induced by pentobarbital or propofol. However, this action of acupuncture was not modified by naloxone at the doses sufficient to block opiate receptors. Plasma β-endorphin detected by radioimmunoassay was also not markedly changed in rabbits which received similar electrostimulation. Moreover, pretreatment with para-chlorophenylalanine at a dose sufficient to deplete endogenous 5-hydroxytryptamine (5-HT) failed to influence the action of EA. Mediation of endogenous opioids and/or 5-HT in this action of EA was then ruled out. Prazosin reversed the sleeping time decreasing action of acupuncture in a dose-dependent manner. Also, the action of acupuncture was eliminated in rabbits which received intracerebroventricular injection of guanethidine at a dose which could block noradrenergic nerve terminals. It is suggested that stimulation of Jen-Chung point through EA can activate noradrenergic neurotransmission in the brain, which in turn reduces the central nervous depressive activity of anesthetics.

Anesthesiologist-directed anesthetic preoperative evaluation clinic (APEC) is used to prepare patients to receive anesthesia for surgery. Studies have shown that APEC can reduce preoperative tests, consultations, surgery delays and cancellations. APEC with video-teaching has been purposed as a medium to provide comprehensive information about the process of anesthesia but it has not been practiced in small groups of patients. It is rational to assume that video-teaching in a small group patients can provide better information to patients to understand the process of anesthesia and in turn improve their satisfaction in anesthesia practice. This study was designed to evaluate the difference of satisfaction between patients who joined in small group video-teaching at APEC and patients who paid a traditional preoperative visit in the waiting area, using questionnaire for evaluation.Totally, 237 eligible patients were included in the study in a space of two months. Patients were divided in two groups; 145 patients joined the small group video-teaching designated as study group and 92 patients who were paid traditional preoperative visit at the waiting area served as control. All patients were requested to fill a special questionnaire after postoperative visit entrusted to two non-medical persons.There were significantly higher scores of satisfaction in anesthesia inclusive of waiting time for surgery in the operation room, attitude towards anesthetic staffs during postoperative visit and management of complications in patients who were offered small group video-teaching in comparison with patients of traditional preoperative visit.The results indicated that APEC with group video-teaching could not only make patients more satisfied with process of anesthesia in elective surgery but also reduce the expenditure of hospitalization and anesthetic manpower.

Minimizing the time of anesthesia emergence can facilitate faster patient turnover in the operating rooms of a busy surgery center. According to Lin's new concept of inhalation uptake, after turning off the vaporizer under close-circuit anesthesia (CCA) with a very low fresh gas flow rate, the concentration of desflurane decreases at a slow rate. The aim of this study was to determine if earlier cessation of desflurane supply would shorten the emergence time and at the same time register the changes of desflurane concentration in the circuit after turning off the vaporizer.30 patients were randomly assigned to two groups, i.e., the control group and the study group. In the control group, the desflurane supply was continued up till the end of the operation, while in the study group the desflurane supply was cut off prior to the suturing the skin. In the study group, data regarding the hemodynamic changes, time from turning off desflurane with high flow washout to wakefulness, and the inspired as well as the expired desflurane concentrations at the low-flow anesthetic phase were collected. The time required from high flow washout to emergence was recorded in all patients. Inter-group and intra-group data were analyzed with nonparametric 2-independent-samples Mann-Whitney test and 2 related-samples Wilcoxon signed ranks test, respectively.Under CCA with similar surgical duration, the patients in the study group emerged from anesthesia significantly faster than those in the control group (5.6 +/- 1.9 min versus 8.8 +/- 2.3 min; P0.05), without molestation of stable hemodynamic signs. At the low-flow wash-in stage, the inspired desflurane concentrations were significantly higher than the expired ones from 0 to 2nd min; no significant difference was noted from the 3rd to 6th min, but after which the expired concentrations were significantly higher. Desflurane concentrations decreased most noticeably during the first 5 min (0.35 +/- 0.14%), and then the decrease was moderating from 6th to 10th min (0.21 +/- 0.58%) and staggered from 11th to 15th (0.14 +/- 0.06%). The mean duration of low flow wash was 25.6 +/- 11.6 min. No patient reported awareness during surgery.Ceasing desflurane supply earlier in CCA (250 mL/min) significantly shortens emergence time without significant hemodynamic changes.

This report cites the usefulness of fiberoptic scope-guided endotracheal tube intubation through a classical laryngeal mask airway (LMA) during spontaneous breathing. Treacher Collins Syndrome (TCS) is a condition where airway management is stressful to anesthesiologists. We report a pediatric patient with TCS undergoing cleft palate repair. The patient had a history of sleep apnea syndrome, chronic lung disease, and congenital heart disease. Intubation by rigid laryngoscopy was unsuccessful at the first attempt. One month later, under spontaneous ventilation, tracheal intubation was smoothly performed with the use of a fiberoptic scope through an LMA under intravenous anesthesia with propofol. Fiberoptic scope-guided endotracheal intubation through an LMA with the push of another ETT of the same size to curb the back slippage of the endotracheal tube already inserted in the trachea can be easily and safely performed under spontaneous breathing in a pediatric patient with TCS.

Nitric oxide (NO) has been shown to play a dual role as a neuroprotectant and a neurotoxin in cerebral ischemia. Free radical scavengers protect brain tissue from ischemic injury. Consequently, we examined the neuroprotective action of NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO), in cerebral ischemia induced by permanent middle cerebral artery occlusion (MCAO) in rats and mice.All experiments were performed in a randomized fashion. In the first series of experiments, adult Sprague-Dawley rats (n = 31) subjected to permanent MCAO were treated with carboxy-PTIO (0.3, 0.6 mg/kg) or vehicle (normal saline) injected intraperitoneally (IP) 1 hr before permanent MCAO. In the second series of experiments, adult C57BL/6NCrj mice (n = 49) were treated with carboxy-PTIO (0.6, 1.2 mg/kg) or vehicle saline 30 min following MCAO. Neurobehavioral scores were determined 22-24 hr following permanent MCAO and infarct volumes determined by quantitative image analysis of 2, 3, 5-triphenyltetrazolium (TTC)-stained brain sections.Pre-treatment with carboxy-PTIO at 0.6 mg/kg IP in rats significantly attenuated infarct volume (19.9 +/- 2.9%; n = 10) as compared with vehicle-treated controls (29.2 +/- 2.7%; n = 16), but not at 0.3 mg/kg (28.3 +/- 8.4%; n = 5). Post-MCAO treatment in mice with 0.6 mg/kg carboxy-PTIO (30.3 +/- 3.9%; n = 16) significantly attenuated infarct volume as compared with vehicle-treated controls (46.1 +/- 2.8%; n = 18).These data demonstrate that NO scavenger, carboxy-PTIO, provides significant ischemic neuroprotection when given as a pre-treatment as well as after the onset of permanent focal ischemia in two animal species.

We evaluated paravertebral transcutaneous electrical nerve stimulation (TENS) as a means of enhancing anesthesia during hysterectomy. Patients were randomly assigned to experimental (n = 21) and control (n = 20) groups. Anesthesia with isoflurane was performed uniformly for all patients. Paravertebral (T6 and T7) TENS (50 mA, 15 Hz, continuously) was applied in the experimental group. After 15 min of isoflurane, a lower abdominal, skin-to-adipose-tissue incision was made. Seventeen of 21 patients in the experimental group showed no arm or leg movements during the incision, compared to 8 with 20 patients in the control group (P = 0.007). TENS deserves further exploration as an adjunct technique for general anesthesia.

The objective of the current study was to determine the direct effect of propofol on intact isolated rabbit heart using the modified Langendorff model.Eighteen rabbits were decerebrated under light ether anesthesia. Their hearts were then excised and prepared pursuant to the modified Langendorff model. Left ventricular pressure, left ventricular contractility (dp/dt) and heart rate were recorded in the absence of propofol and in the presence of propofol of four different concentrations (1, 5, 25, 50 mg/L). In one group of hearts (N=11) the heart rate was not paced. In another group of hearts (N=7), the hearts were paced (during the control period and in propofol of each concentration) at a rate slightly higher than control rate and then allowed to revert to original state; pressure and contractility were measured and taken at both paced and unpaced rates.In the unpaced group of hearts, a significant dose-dependent, negative effect on both left ventricular pressure and contractility was found at the two higher propofol concentrations (25 and 50 mg/L). A significant heart rate decrease was also revealed at these two concentrations. In the paced group, the left ventricular pressure and dp/dt also decreased significantly at higher propofol concentrations, and they did not return toward control values even though the heart was paced at the baseline unpaced rate.Propofol depressed left ventricular pressure and contractility and heart rate in a dose-dependent manner at higher concentrations. These negative cardiac effects were independent of changes in heart rate.

Intrathecal midazolam acts synergically with other anesthetics to relieve surgical pain, and the drug combination may decrease complications attributable to each component drug. This prospective study was to determine the spinal effects of low-dose of bupivacaine (5 mg) combined with intrathecal midazolam (2 mg) in diabetes mellitus (DM) patients undergoing foot debridement.Sixty diabetic patients were admitted for foot debridement under spinal anesthesia were equally divided into two groups. Group 1 (M) received 7.5 mg of hyperbaric bupivacaine; group 2 (M+M) received 5 mg of hyperbaric bupivacaine combined with 2 mg of midazolam intrathecally. The intensity of motor block was assessed with modified Bromage scale 20 minutes after injection, and at 0, 30, 60, 90 and 120 min after arriving at the post anesthesia care unit (PACU). Pain score was assessed with a 10 cm visual analog scale (VAS, 0 = no pain and 10 = intolerable pain) at 0, 1, 2, 6 h and 24 h postoperatively.Anesthesia was smooth in all patients except one in group M, whose analgesia was inadequate and general anesthesia was given to complete the surgery. The number of patients who sustained moderate to severe pain (VAS5) was significantly less in the M+M group than in M group as accessed 6 and 24 h postoperatively. The requirement of additional analgesic as reinforcement was significantly less in the M+M group than in the M group within the space of 24 h postoperatively. Recovery of motor function was significantly faster in the M+M group.The combination of intrathecal midazolam and bupivacaine was a safe and effective anesthetic technique, and it also provided early recovery of motor function and reduced the requirement of analgesics postoperatively.

UNLABELLED We report an unexpected difficult ventilation with a double-lumen endotracheal tube in a patient receiving left upper lobe lung mass resection. The manufacturing defect in both limbs of the Opti-Port Right Angle Double Swivel Connector of the double-lumen tube resulted in this problem. This defect is difficult to localize by the usual recommended methods. We discuss a modified algorithm for difficult ventilation with a double-lumen endotracheal tube. IMPLICATIONS Difficult ventilation occurred during general anesthesia as the result of a manufacturing defect in both limbs of the connector of the double-lumen endotracheal tube. The problem was resolved with a careful approach, and there were no serious consequences.

Spinal anesthesia has been widely used in clinical setting with relatively high incidences of hypotension and bradycardia. Lowering the dosage of local anesthetics is one of the methods to mitigate the side effects. This study was to evaluate the feasibility of lowering the dosage of tetracaine in spinal anesthesia for patients undergoing anorectal surgery.Thirty patients scheduled for anorectal surgery were studied. Patients were randomly divided into experiment (n = 15, 3.0 mg of tetracaine) and control groups (n = 15, 6.0 mg of tetracaine). The extent of analgesia was assessed by loss-of-sensation to pinprick. Dermatomic level of the sensory block was evaluated and recorded every minute for 10 minutes. BP and HR were recorded at 3-min interval for the 10-min in the study period. Numeric data were statistically analyzed with Student's t-test. The categorical data were compared using the chi-square test. P-value less than 0.05 was considered statistically significant.Ten min after the injection, the mean peak level of sensory block reached T12 for experiment and T9 for control groups. A noticeable difference in frequency of hypotension between two groups was found though it was not statistically significant (P = 0.08). Incidences of moderate bradycardia and severe bradycardia were similar in both groups, being 13.3% and 6.7% respectively.This study confirmed that lowering the dosage of tetracaine to 3.0 mg could equally provide adequate spinal anesthesia for anorectal surgery. The reduced dosage has the tendency of reducing the rate of hypotension, but apparently it does not reduce the incidence of bradycardia.

Although propofol has been widely used the uncertainties about its pharmacokinetics and pharmacodynamics are still in existence especially on acute infusion model. This study was designed to observe the changes of the arterial and superior vena cava blood concentrations of propofol during cardiopulmonary bypass and to see whichever site is more appropriate for pharmacodynamic studies of propofol.Eight patients undergoing cardiopulmonary bypass were infused rapidly with propofol. Samples were collected concurrently from bypass arterial side (Ca) and superior vena cava (Cv) side at 0, 0.5, 1, 1.5, 2, 5, 10, 20, 30, and 40 minutes after infusion and analyzed with high pressure liquid chromatography (HPLC). Arterial blood pressure was also recorded at the same time.After administration, the concentration at Ca side was significantly higher than that at the corresponding Cv side from 0.5 to 5 min. The concentration at Ca side peaked at 0.5 min, then decreased rapidly and crossed the Cv curve at approximately 10 min. Thereafter Cv side concentration was slightly higher than that of Ca side. The mean arterial blood pressure decreased significantly from 1 to 20 min after injection. The change in Cv side was significantly consistent with the blood pressure change in the distribution phase (r = 0.78, r2 = 0.61 P0.001) (0 to 5 min).There was a significant arteriovenous concentration difference of propofol after a rapid infusion in the cardiopulmonary bypass model. The hypotensive effect of propofol in the distribution phase can be predicted better on Cv side.

UNLABELLED In a double-blinded study, we compared conventional dose tetracaine (8 mg), small-dose tetracaine (4 mg) with added fentanyl and epinephrine, and small-dose tetracaine (4 mg) with added fentanyl subarachnoid anesthesia. Forty-five patients scheduled for transurethral resection of prostate (TURP) under subarachnoid anesthesia were randomly assigned to Group 1 (8 mg hyperbaric tetracaine), Group 2 (4 mg hyperbaric tetracaine, 10 microg fen-tanyl, and 0.2 mg epinephrine), and Group 3 (4 mg hyperbaric tetracaine, 10 microg fentanyl, and 0.2 mL saline). Evaluations were performed after spinal anesthesia. Subarachnoid block was successful in all patients except one in Group 1, who required general anesthesia by mask. The median peak sensory levels 10 min after the induction of spinal anesthesia in Group 1 was T8, which was significantly higher than Group 2 and Group 3 (P < 0.05). The time of sensory and motor recovery in Group 3 was less than in Groups 1 and 2 (P < 0.05). Hypotension was observed in four patients in Group 1 and none in Groups 2 and 3. We conclude that small-dose 4-mg hyperbaric tetracaine plus 10 microg fentanyl might provide adequate anesthesia and fewer side effects for TURP when compared with the conventional (8 mg) dose. IMPLICATIONS Small-dose hyperbaric tetracaine (4 mg with 10 microg fentanyl added) may provide adequate anesthesia and fewer side effects for transurethral resection of the prostate.

In this study, Jen-Chung (J-C) point was stimulated by electroacupuncture (EA) in 10 patients, and by placebo treatment in 10 controls, immediately after termination of inhalation for 15 min. During the postoperative recovery period, plasma catecholamine (CA) levels were assessed before (0) and 15 and 30 min after treatment. The time from cessation of inhalation to the first eye opening and to extubation did not differ between groups. The plasma catecholamine levels increased by 30% from 0 to 15 min in the control group but decreased by 6% in the EA group. The levels at 30 min were approximately the same as at time 0. The change in catecholamine levels from 0 to 15 min was significantly lower (P < 0.02) in the EA groups than the control group.