Extended spinal anaesthesia using a spinal micro-catheter was used as a primary method of anaesthesia for elective colorectal cancer surgery in 68 high risk patients over a 14-year period in our institution. The technique was also useful in eight elective and 13 emergency abdominal surgeries. All patients suffered from severe chronic obstructive airway disease requiring multiple inhalers and drugs (ASA III). Thirty nine of these patients also suffered from angina, myocardial infarction, diabetes and other systemic diseases (ASA IV). Surgery included right hemicolectomy, left hemicolectomy, total colectomy, sigmoid colectomy, Hartman's resection, anterior resection of rectum, abdominoperineal resection, cholecystectomy (open and laparoscopic) and obstructed inguinal hernia requiring laparotomy. Spinal anaesthesia was performed under strict aseptic conditions with a 22 gauge spinal needle with a mixture consisting of 2.75ml of 0.5% heavy bupivacaine and 0.25ml of fentanyl (25microg). This was followed by placement of a spinal micro-catheter and the duration of anaesthesia was extended by intermittent injection of 0.5% isobaric bupivacaine. Brief hypotension occurred in 12.4% of patients during the establishment of anaesthetic block height to T6-7 and was duly treated with intravenous administration of fluid and ephedrine hydrochloride. Good anaesthesia resulted in all patients except for brief discomfort in some patients during hemicolectomy surgery possibly due to the dissection and traction on the peritoneum causing irritation to the diaphragm. The use of sedation was avoided. General anaesthesia was administered in one patient and this patient required postoperative ventilation and cardiovascular support in the Intensive Care Unit. The spinal micro-catheter was removed at the end of surgery. Postoperative pain relief was obtained by administering intravenous morphine through a patient controlled analgesia machine in the critical care ward area (High Dependency Unit). There was a low incidence of minor postoperative side effects such as nausea (14.6%), vomiting (7.9%), minor post dural puncture headache (5.6%) and pruritus (5.6%). We conclude that spinal anaesthesia with a micro-catheter may be used as a primary method of anaesthesia for colorectal cancer surgery and other major abdominal surgery in high-risk patients for whom general anaesthesia would be associated with higher morbidity and mortality.

OBJECTIVE To evaluate the effect of intrathecal pumping tramadol on cell-mediated immunity in rats with formalin inflammatory pain. METHODS Thirty-two Sprague-Dawley adult male rats weighting 250 approximately 300 g were randomly divided into 4 groups (n=8 in each group):Saline group (NS) and 3 tramadol groups (T1,T2,and T3). The rats were anesthetized with intraperitoneal chloral hydrate (300 approximately 350)mg/kg. Microspinal catheter was inserted into the subarachnoid space at the lumber region according to modified Yaksh techniques. In the tramadol groups,after 5 days tramadol was continuously infused through the spinal catheter at 50 (T1),25 (T2), and 12.5 microg/h (T3) for 7 days. In the NS group normal saline was continuously infused instead of tramadol. On Day 7 formalin (5%, 50 microL) was injected into the plantar surface of the left hindpaw. The number of flinches, lickings and total time of licking was recorded for 60 min.Pain intensity scoring(PIS)(0 approximately 3;0= no pain, 3=severe pain) was used to assess the antinociceptive effect of intrathecal tramadol. The rats were killed after the evaluation of pain intensity. Body weight and spleen weight were measured and spleen index (spleen weight/body weight) was calculated. T-lymphocyte function was evaluated based on Concanavalin-A(ConA) induced splenocyte proliferation. A modified lactic acid dehydrogenase(LDH) release assay was done to assess the NK cell activity. Phenotypic expressions of cell surface markers of T lymphocyte subsets (CD3+, CD3+ CD4+, CD3+ CD8+, and CD4+/ CD8+) and NK cell(CD161+) in the spleen were analyzed by flow cytometry. RESULTS The PIS scores were significantly lower in the T1,T2,and T3 groups than those in the NS group. The spleen index and splenocyte proliferation induced by ConA were significantly suppressed in the T1 group,and the phenotypes of T lymphocyte subsets were significantly changed,but no significant difference was found in the T2 and T3 groups compared with the NS group. There were no differences in NK cell activity in the 3 tramadol groups from the control group. CONCLUSION Intrathecal pumping tramadol has significantly antinociceptive effect. Intrathecal pumping higher dosage tramadol (50microg/h) suppresses T lymphocyte proliferation and alteres T lymphocyte subset phenotype but does not affect NK cell activity. General analgesic dosage tramadol (25 and 12.5 microg/h) has no effect on the immune function.

OBJECTIVE To observe the effect of propofol combined with flurbiprofen axetil for abortion anesthesia. METHODS Eighty ASA I - II induced abortion patients were randomly divided into 4 groups. Group I was administrated 1 microg/kg with tramadol first, after 10 minutes with 2 mg/kg propofol. Group II was administrated with 1 mg/kg tramadol first, after 10 minutes with 2 mg/kg propofol. Group III was administrated flurbiprofen axetil 50 mg first, after 10 minutes 2 mg/kg propofol. Group IV was administrated propofol 2 mg/kg. The speed of intravenous injection of propofol was 100 mg/min in all groups. Induction time, recovery time, propofol dosage, HR, BP, SpO2, and side effect were recorded. The anesthesia effect was judged by operation doctors. RESULTS Propofol consumption and awaken time in Group IV was more than those of other groups. The number of patients in Group I with minimum value of SpO2 in the operation (85%- 90% or SpO2<85%) was higher than that of other groups (P<0.05). The number of patients in Group I and II with the tongue falling backwards during anesthesia, with post-anesthesia nausea and vomit was higher than that of other groups (P<0.05). Incidences of post-anesthesia excitement or delirium were higher than other groups. Fewer patients in Group IV showed a good level anesthesia effect than other groups. The post-operative hypogastric pain of VAS score (0 - 2) in Group III was better than others. CONCLUSION Propofol combined with flurbiprofen axetil gives more efficient anesthesia for induced abortion patients in gynecology department. It can not only have satisfactory anesthesia effect, but also decrease adverse effects and obtain better depression effects to the post-operative hypogastric pain.

OBJECTIVE To compare the anaesthetic effect and hemodynamic changes between the continuous spinal anaesthesia(CSA) and combined spinal-epidural anaesthesia (CSEA) in patients for uterectomy. METHODS Sixty patients undergoing uterectomy were randomly divided into two groups: CSA group and CSEA group. Spinal anesthesia was performed at L2-3 interspace. An initial subarachnoid bolus of 0.5% hyperbaric bupivacaine 2 ml was injected in the CSA group; if analgesia did not reach T8, supplemental bupivacaine was injected by titrate incremental doses. In the CSEA group, epidural anesthesia was performed at T12-L1 with a catheter inserted into the epidural space for anesthesia maintenance, and then 0.5% hyperbaric bupivacaine 3 ml was injected to the subarachnoid at L2-3. The levels and times of sensory and motor block and hemodynamic changes were measured and analysed. RESULTS The anesthetic dosage of the CSA group was smaller than that of the CSEA group (group P < 0.05). The times of sensory block to T8 or the maximal level and motor block were more rapid in the CSEA group than those of the CSA group (P < 0.05). Mean arterial pressure (MAP), which decreased significantly, was related with the baseline in the two groups; the time was 15 min and 25 min in the CSEA group and CSA group respectively (P < 0.05). There was no difference in the maximum decline of MAP in the two groups (P < 0.01). CONCLUSION CSA is a safe technique of spinal anesthesia with small anesthetic dosages, more reliable and hemodynamically stable in patients for uterectomy.

BACKGROUND Encephalopathy is a common complication of sepsis, and its onset can occur at any stage of sepsis and implies worse prognosis. However, the incidence, epidemiology, and pathogenesis of sepsis-associated encephalopathy remain controversial. The purpose of this study was to investigate the epidemiological features and risk factors for sepsis-associated encephalopathy. METHODS Our retrospective study included all patients with sepsis admitted to our intensive care unit from 2008 to 2011. After excluding 91 patients, 232 patients were assigned to either a sepsis-associated encephalopathy group or sepsis without encephalopathy group. Between-group differences in baseline patient data including vital signs, disease severity, pathogens, sites of infection, biochemical indicators, and time on a mechanical ventilator, intensive care unit (ICU) stay, and 28-day mortality rate were analyzed. RESULTS The incidence of sepsis-associated encephalopathy was 17.7%. The sepsis-associated encephalopathy group had significantly higher 28-day mortality (56.1% vs. 35.1%; P=0.013), spent a significantly longer time on a ventilator ((8.2±2.2) days vs.(2.9±0.4) days; P=0.021), and had a significantly longer ICU stay ((12.4±2.4) days vs.(7.1±0.6) days; P=0.042). Acute physiology and chronic health evaluation II score, Glasgow coma scale, heart rate, blood lactate, serum sodium, platelets, serum albumin, and pH values were related to the presence of encephalopathy. Patients with biliary tract infections and intestinal infections caused by Staphylococcus aureus, Enterococcus faecium, Acinetobacter spp, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia, were more prone to develop sepsis-associated encephalopathy. CONCLUSIONS Encephalopathy increases mortality rate in septic patients. Clinical intervention to reduce risk factors and thereby morbidity and mortality depends on a correct understanding of the differences between patients with sepsis and patients with both sepsis and encephalopathy.

BACKGROUND Several studies suggest that cyclooxygenase-2 (COX-2) contributes to the delayed progression of ischemic brain damage. This study was designed to investigate whether COX-2 inhibition with parecoxib reduces focal cerebral ischemia/reperfusion injury in rats. METHODS Ninety male Sprague-Dawley rats were randomly assigned to three groups: the sham group, ischemia/reperfusion (I/R) group and parecoxib group. The parecoxib group received 4 mg/kg of parecoxib intravenously via the vena dorsalis penis 15 minutes before ischemia and again at 12 hours after ischemia. The neurological deficit scores (NDSs) were evaluated at 24 and 72 hours after reperfusion. The rats then were euthanized. Brains were removed and processed for hematoxylin and eosin staining, Nissl staining, and measurements of high mobility group Box 1 protein (HMGB1) and tumor necrosis factor-α (TNF-α) levels. Infarct volume was assessed with 2,3,5-triphenyltetrazolium chloride (TTC) staining. RESULTS The rats in the I/R group had lower NDSs (P < 0.05), larger infarct volume (P < 0.05), lower HMGB1 levels (P < 0.05), and higher TNF-α levels (P < 0.05) compared with those in the sham group. Parecoxib administration significantly improved NDSs, reduced infarct volume, and decreased HMGB1 and TNF-α levels (P < 0.05). CONCLUSIONS Pretreatment with intravenous parecoxib was neuroprotective. Its effects may be associated with the attenuation of inflammatory reaction and the inhibition of inflammatory mediators.

The effects of aluminum on water distribution system and human health are mainly attributable to their presence in drinking water. Laboratory experiments were performed to investigate the influence of temperature and pH on the distribution of aluminum species applying alum synthetic water. Aluminum species studied in the experiments included monomeric aluminum, soluble aluminum, suspended aluminum, and polymeric aluminum, which were determined by fluorescence spectrophotometry method. Results indicated that suspended aluminum was the major species at pH 6.5, occupied about 62.2% in the total aluminum mass concentration. While at pH above 7.0, monomeric aluminum was the major species; and varied little as reaction time increased. Polymeric aluminum mass concentration was low at studied water quality condition and also varied little as reaction time increased. The influence of temperature on aluminum species distribution was similar to solution pH; and both could be explained by pOH. Aluminum species in drinking water could be controlled by adjusting the pOH value, which provided theoretical guidance for the operation of the water distribution system and aluminum toxicity control.

OBJECTIVE To investigate the antinociceptive effect of intrathecal (IT) injection of Herpes simplex virus type I (HSV-1) amplicon vector-mediated HPPE on chronic neuropathic pain. METHODS 45 Sprague-Dawley rats underwent chronic constriction. Injury (CCI) of unilateral sciatic nerve and then were randomly divided into 3 equal groups: CCI + normal saline group, undergoing insertion of microspinal catheter into the subarachnoid space at the lumber region and intrathecal delivery of NS, CCI + pHSVIRES-LacZ (SHPZ) group undergoing intrathecal delivery of and recombinant HSV-I amplicon vector pHSVIRES-HPPE-LacZ containing human pre-proenkephalin (HPPE) gene, and CCI + blank vector (SHZ) group receiving pHSV-HPPE-LacZ. Another 15 rats underwent sham operation to be used as control group. One week after IT administration 9 rats from each group were killed with their lumber segments of spinal cord removed to detect the expression of LacZ by X-gal staining, HPPE mRNA expression by RT-PCR, and L-enkephalin (L-EK) content by radioimmunoassay. Paw mechanical withdrawal threshold (PMWT) and paw withdrawal thermal latency (PWTL) were measured before CCI (baseline) and 3 days after CCI and then once a week for 5 weeks after IT administration. RESULTS After IT administration of SHPZ expression of HPPE mRNA was detected in the spinal cord. One week after the IT injection the L-EK level of the SHPZ group was (748 +/- 185 ng/L), significantly higher than those of the Sham operation, NS, and SHZ groups [(452 +/- 89),(453 +/- 92), and (451 +/- 99) ng/L respectively, all P < 0.05]. The PWMT and PWTL levels of the SHPZ group were significantly increased since 1 week after the IT administration in comparison with the baseline values and those of the other 3 groups (all P < 0.05), and these effects peaked in the third week and then lasted to the fifth week. However, the threshold to mechanical and thermal stimuli was not affected by intrathecal delivery of vehicle or SHZ compared with the threshold before intrathecal delivery. CONCLUSIONS Intrathecal administration SHPZ can produce significant analgesic effects on chronic neuropathic pain in rats.

OBJECTIVE To examine the characteristics of drug-induced fatal adverse effects in the United States from 1999 to 2004 and put forward suggestions for China's control of drug-induced adverse effects. METHODS The data came from the compressed mortality file of Centers for Disease Control and Prevention (CDC) of the United States. Drug-induced mortality was used to analyze the effects of gender, race, age, and drug on drug-induced fatal adverse effects. RESULTS During 1999-2004, 1 700 persons died of drug-induced adverse effects (mortality, 0.10/100,000). No difference was found in mortality between males and females. The drug-induced mortalities of whites, blacks and Native Americans, and other racial groups were respectively 0.10, 0.12, and 0.04 per 100,000 persons. The mortality increased quickly with the increase of age since the age group of 5-9. In this period, the 5 most common drugs that led to deaths were:(1) agents primarily affecting blood constituents;(2) analgesics, antipyretics, and anti-inflammatory drugs;(3) primarily systemic agents;(4) systemic antibiotics; and (5) hormones and their synthetic substitutes and antagonists, not elsewhere classified. At the age group of 20-84, 3 most common drugs leading to deaths for whites were: anticoagulants,opioids and related analgesics, and insulin and oral hypoglycaemic drugs. For blacks and Native Americans, they were: hydantoin derivatives, anticoagulants, and anaesthetic, unspecified. For people ages older than 84, anticoagulants, opioids and related analgesics, and drug or medicament, unspecified, were the 3 most common drugs resulting in deaths. For the rest of racial groups, the number of deaths caused by all kinds of drugs was less than 3. CONCLUSION Obvious differences on race, gender, age, and drug were found for drug-induced fatal adverse effects in the United States during 1999-2004, and these differences should be considered by the government when interventions are developed. China can learn something from the United States in controlling drug adverse effects, and improve its surveillance system of drug adverse effects as soon as possible.

OBJECTIVE To determine an optimal clinical dose of ketamine after comparing the efficacy and security of 3 low dose ketamines mixed with butorphanol in the postoperative continuous intravenous analgesia. METHODS Eighty ASA (American Society of Anesthesiologists) I-II patients scheduled for elective gynecological surgery under general anesthesia were divided randomly into 4 groups (n=20): Group B received butorphanol 3 microg/(kg x h);Group BK1 received butorphanol 2 microg/(kg x h) mixed with ketamine 60 microg/(kg x h); Group BK2 received butorphanol 2 microg/(kg x h) mixed with ketamine 90 microg/(kg.h); and Group BK3 received butorphanol 2 microg/(kg x h) mixed with ketamine 120 microg/(kg x h). Continuous intravenous infusion pump was used when the patients had obvious pain (visual analgesia scale of five), and the bolus infusion (4 mL) was given before the operation, and continuous infusion at 2 mL/h. In the postoperative period, pain was assessed using visual analogue scale (VAS) at 2,6,12,24, and 48 h.At the same time, Ramsay scores and adverse effects were recorded. RESULTS There was no significant difference in the adverse effects and the postoperative mean arterial pressure, heart rate, respiratory rate values, and pulse oxygen among the 4 groups. Postoperative VAS values in Group BK3 was the lowest, followed by Group BK2. There was no significant difference between Group BK1 and Group B. The incidence of somnolence in Group B was higher than that in Group BK1, BK2 and BK3(P<0.05). CONCLUSION Ketamine in subanaesthetic dose added to butorphanol for postoperative continuous intravenous infusion has a better postoperative analgesic effect and sedation. It can effectively spare butorphanol consumption without increasing adverse effects. The optimal combined dose is 90-120 microg/(kg x h).

Objective  To evaluate the intraoperative efficacy of intrathecal anaesthesia with hyperbaric bupivacaine 0.5% and morphine 1% solution (HIA) in dogs undergoing hind limb orthopaedic surgery, using the cardiovascular response to surgical stimulation and to report the perioperative side effects. Study design  Retrospective clinical study. Animals  Forty-three dogs that underwent general anaesthesia for hind limb orthopaedic surgery between 2010 and 2011. Methods  The anaesthesia records of dogs that received HIA were reviewed. The bupivacaine and morphine doses were calculated based on body mass (BM) and spinal cord length (SCL). Cardiovascular response (CR) to surgical stimulation, the incidence of hypotension, bradycardia, urinary retention, pruritus and offset of motor block were all reported. The intraoperative time-to-event probability of CR was analyzed using Kaplan-Meier survival analysis. Results  The median (range) bupivacaine dose related to BM was 0.57 (0.40-0.78) mg kg(-1), while that related to SCL was 0.13 (0.08-0.19) mg cm(-1). A CR was observed in 3/39 (8%) dogs within the first hour after intrathecal injection (Ii) and in 9/39 (23%) dogs over the entire duration of surgery. At 70 minutes from Ii the event-free probability of CR fell below 80%. Hypotension was observed in 12/39 (31%), bradycardia in 6/39 (15%), pruritus in 3/39 (8%), and urinary retention in 3/39 (8%) dogs respectively. Five hours after Ii, 35/39 (89%) dogs were able to walk with only residual ataxia. Conclusions and clinical relevance  Intrathecal anaesthesia with hyperbaric bupivacaine 0.5% and morphine 1% solution provided effective intraoperative antinociception up to 70 minutes in dogs undergoing hind limb surgery. The technique of HIA can provide effective analgesia during short hind limb surgeries in dogs.

BACKGROUND The directional flow of injection through a Whitacre needle can be used to modify the level of sensory blockade. We hypothesized that injection of hyperbaric local anesthetic through a Whitacre needle with the bevel oriented laterally can produce a more symmetric sensory block. METHODS Patients scheduled for lower limb surgery under spinal anesthesia with the patient in lateral decubitus position were randomized to receive 10 mg, 0.5% hyperbaric bupivacaine with the Whitacre needle orifice in 1 of 2 orientations, cephalad and lateral. The patient's position was maintained for 15 min after the injection, and sensory blocks were recorded. The primary outcome was the sensory levels between the dependent and nondependent side. The Wilcoxon-Mann-Whitney U-test odds was used to compare unpaired nonparametric data. For the paired samples, 95% confidence intervals (CI) of differences between group medians were calculated using the Hodges-Lehman estimator for the median difference in number of blocked segments. RESULTS There was no significant difference in block level between dependent and nondependent sides in the lateral group. The Hodges-Lehmann point estimator was 0.5% and 95% CI was 0-2.5, suggesting a more symmetric sensory block in patients in the lateral decubitus position maintained for a sufficient period of time. A significantly lower level of blockade was noticed on the nondependent side compared to the dependent side in the cephalad group. The Hodges-Lehmann point estimator was 2.5 segments and 95% CI was 0.5-5. CONCLUSIONS Injection of 10 mg of 0.5% hyperbaric bupivacaine with the bevel of the Whitacre needle oriented laterally produces more symmetric sensory levels of blockade between the dependent and nondependent sides.

OBJECTIVE Observe the potency of various drugs doses as milliliters of 0.5% heavy bupivacaine with or without fentanyl for spinal block in transurethral cystoscopic procedures. These doses were calculated from patients and drugs 'characteristic risk factors that interfered with intrathecal drugs spread as weight, height, age, volume, and baricity. Various doses of fentanyl were also added to increase potency of block as necessary except the oldest group. MATERIAL AND METHOD One hundred fifty two ASA I-III adult patients, of both sexes, aged 19 to 80 years, and scheduledfor elective transurethral cystoscopic surgery, were allocated into four groups of age and doses (formulated by earlier studies and the authors' own experiences). Group I was the 16 to 59-years-old, n=32, and received [0.5% hyperbaric bupivacaine in ml (= 5/4 body surface area)+ 12.5 mcgfentanyl]. Group 2 was the 60 to 70-years-old group, n=65, and received [0.5% hyperbaric bupivacaine in ml (= I body surface area)+ 10 mcgfentanyl]. Group 3 was the 71 to 75-years-old group, n=35, and received[0.5% hyperbaric bupivacaine in ml (= 3/4 body surface area)+ 7.5 mcgfentanyl]. Finally, group 4 was the >75 years old, n=20, and received [0.5% hyperbaric bupivacaine in ml (= 3/4 body surface area) without fentanyl]. The statistical analysis included hemodynamic parameters and side effects. Post-hoc analysis was done using ANOVA among the four groups and logistic regression to find any association with successful outcomes. RESULTS Eighty-eight percent of the blocks were successful without analgesic supplements (VAS <2). The mean onset time (sensation loss to T10) of patients started at 5.4 +/- 1.4 minutes, time to regress to T11 (expected duration of operable time) was 119.7 +/- 37.9 (45-255) minutes, time to leg up (expected ready to discharge) 132 +/- 39 (65-250) minutes. Hypotension was strikingly low in the study (8%), while bradycardia was 16%, similar to other reports. The other side effects were pruritus 2%, nausea 7%, and vomiting 1%. Total successful without any supplement was 87.5% but increase to 93.4% with low dose of fentanyl <50 mcg intravenously. The formulas predicted less successful blocks for the oldest age groups that LA dose less than 1 BSA, and fentanyl added had a significant weight on the outcomes (OR 1.2635, 95% CI 1.0719-1.4894). CONCLUSION Age and body surface area guided spinal anesthesia is safe. The dose of bupivacaine is lower when combined with fentanyl. Furthermore, hemodynamic stability is better. The technique is suitable for transurethral procedure within 60 minutes but not in longer operation time. Additionally, it needs patients' cooperation due to less potent of motor and pressure sensation block.

We performed a prospective, double-blinded study in 20 patients undergoing gynecologic surgery with lower abdominal incision, to investigate characteristics of intrathecal hyperbaric levobupivacaine compared with isobaric levobupivacaine. We randomly assigned them to receive 3 mL of either isobaric or hyperbaric 0.42% levobupivacaine intrathecally. We found that hyperbaric levobupivacaine, compared with isobaric levobupivacaine, spread faster to T10 level (2.8 ± 1.1 versus 6.6 ± 4.7 minutes, P = 0.039), reached higher sensory block levels at 5 and 15 minutes after injection (T8 versus L1, P = 0.011, and T4 versus T7, P = 0.027, resp.), and had a higher peak level (T4 versus T8, P = 0.040). Isobaric levobupivacaine caused a wider range of peak levels (L1 to C8) compared with hyperbaric form (T7 to T2). The level of T4 or higher reached 90% in the hyperbaric group compared with 20% in the isobaric group (P = 0.005). Our results suggest that hyperbaric levobupivacaine was more predictable for sensory block level and more effective for surgical procedures with lower abdominal approach. Hyperbaric levobupivacaine seems to be suitable, but the optimal dosage needs further investigation.

Spinal anesthesia is a special regional anesthetic technique that is applied in lower limb orthopedic and other surgical procedures made below the transverse umbilical line, which is able to produce a neuraxial central block. The patient's position, together with the baricity of the drug solution injected, is a variable that can affect the success of anaesthesia. According to clinical practice, lateral decubitus or the sitting position are to be maintained for a period ranging from 15 to 20 minutes to avoid any possible motion of the injected solution that could cause side effects due to anesthetic being distributed up to thoracic segments. We describe a case of cardiovascular and respiratory effects occurred approximately 65 min after spinal anesthesia with 7 mg of 1% hyperbaric bupivacaine in a patient during change in posture from mild anti-Trendelemburg to supine decubitus. These findings show that a change in posture after spinal anaesthesia with hyperbaric bupivacaine can affect the safety of this anesthesia technique, also after a longer period of time than is usually recommended to avoid the spread of anaesthetic drug.

BACKGROUND No drug, used as adjuvant to spinal bupivacaine, has yet been identified that specifically inhibits nociception without its associated side-effects. AIMS This prospective randomized double-blind study was conducted to evaluate the onset and duration of sensory and motor block as well as perioperative analgesia and adverse effects of dexmedetomidine and magnesium sulfate given intrathecally with 0.5% hyperbaric bupivacaine for spinal anesthesia. MATERIALS AND METHODS A total of 90 patients classified as American Society of Anesthesiologists status I and II scheduled for lower abdominal and lower limb procedures were prospectively studied. Patients were randomly allocated to receive intrathecally either 15 mg hyperbaric bupivacaine plus 0.1 ml (10 μg) dexmedetomidine (group D, n=30) or 15 mg hyperbaric bupivacaine plus 0.1 ml (50 mg) magnesium sulfate (group M, n=30) or 15 mg hyperbaric bupivacaine plus 0.1 ml saline (group C, n=30) as control. The onset time to reach peak sensory and motor level, the regression time for sensory and motor block, hemodynamic changes and side-effects were recorded. STATISTICAL ANALYSIS USED All statistical analyses were performed using INSTAT for windows. Continuous variables were tested for normal distribution by the Kolmogorov-Smirnov test. Data was expressed as either mean and standard deviation or numbers and percentages. Continuous covariates (age, body mass index and height) were compared using analysis of variance (ANOVA). For the times to reach T10 dermatomes, Bromage 3 scale and the regression of the sensory block to S1 dermatome and Bromage scale 0, one-way ANOVA was used to compare the means. The level of significance used was P<0.05. RESULTS The onset times to reach T10 dermatome and to reach peak sensory level as well as onset time to reach modified Bromage 3 motor block were significantly different in the three groups. The onset time to reach peak sensory and motor level was shorter in group D as compared with the control group C, and it was significantly prolonged in group M. We also found that patients in group D had significant longer sensory and motor block times than patients in group M, which was greater than in the control group C. CONCLUSION It was found that onset of anesthesia was rapid and of prolonged duration in the dexmedetomidine group (D). However, in the magnesium sulfate group (M), although onset of block was delayed, the duration was significantly prolonged as compared with the control group (C), but to a lesser degree than in the dexmedetomidine group (D). The groups were similar with respect to hemodynamic variables and there were no significant side-effects in either of the groups.

PURPOSE Unilateral spinal anesthesia is performed to provide restriction of sympathetic and motor block. The purpose of this study is to compare the effect of different speeds of intrathecal injection on unilateral spinal anesthesia. METHODS The patient cohort comprised 66 patients who were placed in the lateral position with the side to be operated on dependent. After dural puncture, the needle aperture was turned towards the dependent side, and hyperbaric 0.5% bupivacaine was injected at a rate of 1 ml/min in Group Slow patients (Group S, n = 33) or 0.5 ml/min in Group Extra Slow patients (Group ES, n = 33). The lateral position was maintained for 15 min. Skin temperature, loss of pinprick sensation, and degree of motor block were recorded. RESULTS There were significant differences in the characteristics of the non-operative side between the groups when on the block. Sensorial block was unilateral in 25 (75.8%) patients in Group S and in 29 patients in Group ES (87.9%) 15 min post-injection. At the end of the operation (approximately 50 min after spinal anesthesia), strictly unilateral anesthesia was present in 31 patients in Group ES (93.9%) and in 22 patients in Group S (66.6%)(p < 0.05). Unilateral sensory and motor block were observed in both groups, and the incidence of strict unilateral block was significantly higher in group ES patients. CONCLUSIONS The result of the study show that the extra-slow injection of hyperbaric bupivacaine provided strictly unilateral sensorial and sympathetic block in 93.9 and 87.9% of the patients, respectively, and that a slow injection of low doses of hyperbaric 0.5% bupivacaine 1 ml was sufficient to provide unilateral spinal anesthesia.

Background. The behaviour of isobaric levobupivacaine in relation to gravity when used in obstetric spinal anesthesia is unclear. Methods. 46 women with ASA physical status 1 undergoing cesarean section were randomly allocated to 2 groups. Spinal anesthesia with 12.5 mg levobupivacaine was performed in the sitting position in all women. Those in the first group were placed in the supine position immediately after the injection, while those in the second group were asked to remain seated for 2 minutes before assuming the supine position. The sensory block level, the onset of sensory and motor blocks, the regression of the sensory block for 2 dermatomes of the sensory block, the first request for analgesics, and the regression of motor block were recorded. Results. No differences in onset times, sensory level, or Bromage score were observed between the two groups. The time of first analgesic request was earlier in the seated group (supine 131 +/- 42 min, seated 106 +/- 29 min, P =.02). Conclusion. Isobaric levobupivacaine in women at term produces a subarachnoid block the dermatomal level of which does not depend on gravitational forces.

INTRODUCTION: Bupivacaine is anesthetic often used in spinal anesthesia in the hyperbaric form (with factory-made incorporated 8.25% glucose), and in isobaric form without additives,(so-called "plain"). Baricity manipulation of local anesthetic is made for the better match of necessary and achieved level of sensor block. Too high block is unnecessary and can compromise the patient's hemodynamic status. OBJECTIVE: To compare gained height and coherence of sensor block using hyperbaric and isobaric 0.5% bupivacaine. PATIENTS AND METHODS: Sixty patients were subjected to the elective operating orthopedic, urological or gynecological surgery in spinal anesthesia. Randomly selected thirty patients received 3 ml of hyperbaric 0.5% bupivacaine, while thirty others received 3 ml of isobaric 0.5% bupivacaine by an identical protocol. After application of anesthesia, the development of all modalities of the block was checked. Finally, after 20 minutes, the height of sensor blocks were determined by an insulin needle (pin-prick test) and that value was taken as the final. RESULTS: All blocks were sufficient to perform surgery. In the hyperbaric group the highest recorded level of the block was first thoracic segment-T1 (3.33%) and the lowest level was seventh thoracic segment T7 (6.66%). In the isobaric group the highest recorded level was T5 (3.33%) and the lowest was L2 (3.33%). Modus as the most frequent value in the series of the hyperbaric group was T5, and in the isobaric T10 (p < 0.01). CONCLUSION: Hyperbaric 0.5% bupivacaine because of the amount of the block may be adequate for all operational procedures that are made in the spinal anesthesia, but sometimes gives unnecessary high block that can give significant changes in the pressure and in the pulse. Isobaric 0.5% bupivacaine gives a very comfortable anesthesia for surgeries in which sensory block of T10 is sufficient.

BACKGROUND AND OBJECTIVES: Unilateral spinal anesthesia has its advantages, especially in patients undergoing outpatient basis surgeries. Low dose, slow speed of administration, and the lateral positioning make easier the unilateral distribution in spinal anesthesia. Isobaric, hyperbaric, and hypobaric solutions of bupivacaine were compared in the unilateral spinal anesthesia in patients undergoing outpatient basis orthopedic surgeries. METHODS: One hundred and fifty patients were randomly divided in three groups to receive 5 mg of 0.5% isobaric bupivacaine (Iso Group), 5 mg of 0.5% hyperbaric bupivacaine (Hyper Group), or 5 mg of 0.15% hypobaric bupivacaine (Hypo Group). The solutions were administered in the L3-L4 space with the patient in the lateral decubitus and remaining in this position for 20 minutes. Sensitive anesthesia was evaluated by the pin prick test. Motor blockade was determined by the modified Bromage scale. Both blockades were compared with the opposite side and among themselves. RESULTS: There was a significant difference between the side of the surgery and the opposite side in all three groups at 20 minutes, but the frequency of unilateral spinal anesthesia was greater with the hyperbaric and hypobaric solutions. Sensitive and motor blockades were observed in 14 patients in the Iso Group, 38 patients in the Hyper Group, and 40 patients in the Hypo Group. Patients did not develop any hemodynamic changes. Postpuncture headache and transitory neurological symptoms were not observed. CONCLUSIONS: Spinal anesthesia with hypobaric and hyperbaric solutions present a higher frequency of unilateral anesthesia. After 20 minutes, isobaric bupivacaine mobilized into cerebrospinal fluid (CSF) resulted in unilateral spinal anesthesia in only 28% of the patients.