Mg Of Bupivacaine Research Articles

The Effect of Levobupivacaine and Bupivacaine on QT, Corrected QT (Qtc), and P Wave Dispersions in Cesarean Section

Background and ObjectivesIn our study we aimed to investigate the effect of bupivacaine and levobupivacaine on QT, corrected QT (QTc), and P wave dispersion durations during spinal anesthesia in cesarean section. MethodsSixty parturients scheduled for elective cesarean section in ASA I-II risk groups were included in the study. Baseline electrocardiographic (ECG) records of the patients were obtained in the operation room. Heart rate (HR), non-invasive blood pressure (NIBP), peripheral oxygen saturation (SpO2) and respiration rates (RR) were recorded. Venous cannulation was performed with 18G cannula and fluid preload made with 10mL.kg-1. Lactated Ringer solution. After fluid preload, second ECG recordings were taken and the patients were randomly separated into two groups. Group B (n = 30) received 10mg of bupivacaine and Group L (n = 30) received 10mg of levobupivacaine for spinal anesthesia. ECG recordings were repeated at 1, 5 and 10minutes after spinal block. HR, NIBP, SpO2, RR and sensory block levels were also recorded at the same time intervals. At predetermined time intervals of spinal anesthesia, P wave dispersion (Pwd), QT dispersion (QTd), and QTc dispersion (QTcd) durations were measured from ECG records. QT and QTc durations are calculated with Bazzett formula. ResultsThere was no difference between two groups according to block levels, hemodynamic parameters, Pwd, QTd, QTc and QTcd durations. ConclusionBupivacaine and levobupivacaine may be preferred in spinal anesthesia in pregnant patients who have extended Pwd and QTcd preoperatively.

A comparison of intrathecal dexmedetomidine, clonidine, and fentanyl as adjuvants to hyperbaric bupivacaine for lower limb surgery: A double blind controlled study

Background:Various adjuvants are being used with local anesthetics for prolongation of intraoperative and postoperative analgesia. Dexmedetomidine, the highly selective 2 adrenergic agonist is a new neuraxial adjuvant gaining popularity.Settings and Design:The study was conducted in prospective, double blind manner. It included 120 American Society of Anesthesiology (ASA) class I and II patients undergoing lower limb surgery under spinal anesthesia after approval from hospital ethics committee with written and informed consent of patients.Materials and Methods:The patients were randomly allocated into four groups (30 patients each). Group BS received 12.5 mg hyperbaric bupivacaine with normal saline, group BF received 12.5 mg bupivacaine with 25 g fentanyl, group BC received 12.5 mg of bupivacaine supplemented 30 g clonidine, and group BD received 12.5 mg bupivacaine plus 5 g dexmedetomidine. The onset time to reach peak sensory and motor level, the regression time of sensory and motor block, hemodynamic changes, and side effects were recorded.Results:Patients in Group BD had significantly longer sensory and motor block times than patients in Groups BC, BF, and BS with Groups BC and BF having comparable duration of sensory and motor block. The mean time of two segment sensory block regression was 147 ± 21 min in Group BD, 117 ± 22 in Group BC, 119 ± 23 in Group BF, and 102 ± 17 in Group BS (P > 0.0001). The regression time of motor block to reach modified Bromage zero (0) was 275 ± 25, 199 ± 26, 196 ± 27, 161 ± 20 in Group BD, BC, BF, and BS, respectively (P > 0.0001). The onset times to reach T8 dermatome and modified Bromage 3 motor block were not significantly different between the groups. Dexmedetomidine group showed significantly less and delayed requirement of rescue analgesic.Conclusions:Intrathecal dexmedetomidine is associated with prolonged motor and sensory block, hemodynamic stability, and reduced demand of rescue analgesics in 24 h as compared to clonidine, fentanyl, or lone bupivacaine.

Effect of electroacupuncture in postanesthetic shivering during regional anesthesia: a randomized controlled trial

BackgroundShivering during regional anesthesia is a common complication and is related to a decrease in the patient’s core body temperature. Previous studies have shown that acupuncture on specific acupoints can preserve core body temperature. The present study evaluated the effect of electroacupuncture in preventing the shivering caused by regional anesthesia.MethodsThis prospective and randomized controlled study analyzed the data from 80 patients undergoing urological surgery, who were classified as ASA I or II. Spinal anesthesia was performed in all patients using 15 mg of bupivacaine. The patients were randomly allocated to receive either placebo acupuncture (Group P, n = 40) or electroacupuncture (Group A, n = 40) for 30 min before administration of spinal anesthesia. Shivering score was recorded at 5 min intervals, with 0 representing no shivering and 4 representing the most severe shivering possible. Heart rate, blood pressure, and tympanic temperature were recorded before the intrathecal injection, and again every 5 min thereafter until 30 min.ResultsAfter spinal anesthesia, the decrease in tympanic temperature was less for Group A patients than Group P, with the difference being statistically significant. After 15 min, 13 patients in Group P attained a shivering score of 3 or more, compared with 3 patients in Group A. Significantly more patients in Group P attained a shivering score of at least 1.ConclusionsThe prophylactic use of electroacupuncture might maintain core body temperature, and may effectively prevent the shivering that commonly develops during regional anesthesia.Trial registrationAustralian New Zealand Clinical Trials Registry ACTRN12612000096853.

Prolonged Nerve Block by Microencapsulated Bupivacaine Prevents Acute Postoperative Pain in Rats

To minimize acute postoperative pain, a new formulation of slowly released bupivacaine was developed. Bupivacaine was microencapsulated at 60% (wt/wt) in poly-lactide-co-glycolide polymers and characterized for physicochemical properties and bupivacaine release kinetics. This formulation was injected around the rat sciatic nerve to produce an antinociceptive effect to toe pinch. Mechanical hyperalgesia following lateral plantar paw incision in rats was assessed for 7 to 14 days when the bupivacaine slow-release formulation was placed at the ipsilateral sciatic nerve and compared with the hyperalgesia that developed with various controls. Bupivacaine was released in vitro at a relatively constant rate over a period of ≈ 72 to 96 hours. Complete antinociception, shown as no response to toe pinch, lasted for 23 ± 7 hours, with a half-recovery time of 42 ± 8 hours after sciatic nerve injection of 0.4 mL of the microspheres delivering 34 mg of bupivacaine. Solutions of 0.5% (wt/vol) bupivacaine-HCl (0.1 mL) produced complete antinociception for less than 2 hours and recovery half-times of 2 hours. Postincisional mechanical hyperalgesia, shown by increased withdrawal responses to von Frey filaments, was absent for 24 hours and was lower than control for 96 hours, when the sciatic nerve was blocked by bupivacaine microspheres, whereas the 0.5% bupivacaine solution reduced postincisional pain for only 4 hours. Corresponding to its far greater functional blocking time, the microsphere-bupivacaine formulation was able to significantly reduce postoperative pain below control levels for up to 4 days. These findings of several days of postoperative pain relief, for an injectable formulation containing a single active agent, present an improved and potentially promising therapy to prevent acute pain after surgery.

Effects of adjunct intrathecal magnesium sulfate to bupivacaine for spinal anesthesia: a randomized, double-blind trial in patients undergoing lower extremity surgery

The aim of this study was to evaluate the effect of additional magnesium sulfate (MgSO(4)) 100 mg to intrathecal (IT) isobaric 0.5% bupivacaine 3 ml on spinal anesthesia in patients undergoing lower extremity orthopedic surgery. In a double-blind randomized clinical trial, 79 American Association of Anesthesiologists (ASA) I or II adult patients undergoing lower extremity orthopedic surgery were recruited. The patients were randomly allocated to receive 100 mg MgSO(4) 5% (0.2 ml) plus 15 mg of bupivacaine 0.5% (MgSO(4) group) or 15 mg bupivacaine 0.5% combined with 0.2 ml normal saline (control group) intrathecally. Response to treatment was assessed as onset and duration of sensory block, the highest level of sensory block, time to complete motor block recovery, duration of spinal anesthesia, and postoperative analgesic requirement. The onset of the sensory block was slower in the MgSO(4) group than in the control group (13.3 vs. 11.6 min, P = 0.04), and the duration of the sensory blockade was significantly longer in the MgSO(4) group than the control group (106.5 vs. 85.5 min, P = 0.001). Total analgesic requirements for 24 h following surgery were lower in the MgSO(4) group than in the control group (96.8 vs. 138.5 mg, P = 0.001). Mean duration of spinal anesthesia was not significantly different between two groups (178.0 vs. 167.4 min, P = 0.23). In patients undergoing lower extremity surgery with spinal anesthesia, the addition of 100 mg IT MgSO(4) to 15 mg bupivacaine without opioid supplement, prolonged the duration of the sensory block, decreased postoperative analgesic consumption, and significantly prolonged the onset of spinal anesthesia.

623 Ultra fast track cardiac surgery and anaesthesia: A collaborative team approach

The advantages of minimally invasive coronary artery bypass grafting (CABG) surgery over conventional CABG include shorter recovery time, overall reduction in morbidity, blood transfusion, greater patient satisfaction, shorter hospital stay, and earlier return to work. In order to explore the opportunities within our practice to improve patient care while at the same time protecting our patients from harm and reducing costs to our financially challenged hospitals, we identified an opportunity to explore the option of bypassing the intensive care unit (ICU) in a highly selected group of patients undergoing minimally invasive coronary artery bypass surgery. This was accomplished through an extensive collaboration between nurses, administrators and physicians alike. A collaborative pathway was constructed for selection of suitable patients by the surgeon and anaesthesiologists based on the grounds of compatible coronary anatomy for minimally invasive coronary artery revascularization. Secondary factors included minimal systemic co-morbidity. A total of 14 patients underwent successful fast track cardiac surgery. There were 12 males and 2 females. They all received preoperative spinal injection of 15 mg of bupivacaine and 3 to 5 mcg/kg of preservative free morphine prior to their general anaesthesia. Using single lung ventilation they underwent Robotic-assisted CABG. Immediately after the revascularization they underwent cardiac catheterization to confirm patency of their graft and simultaneous percutaneous coronary intervention in 2 patients in the hybrid operating suite. Simultaneously, their anaesthetic and neuromuscular blockade was reversed achieving spontaneous respiration. Following clinical confirmation of return of spontaneous respiration, wakefulness and protective airway reflexes, the endotracheal tube was removed, and the patients were transferred to the post anaesthetic care unit (PACU). All patients were monitored in the PACU for 4 to 6 hours before being transferred to the postoperative ward. One patient had to return to the operating room for increase bleeding after 3 hours. He underwent uncomplicated exploration for chest wall bleeding. All patients had patent grafts, no post-operative complications and were extremely satisfied on discharge. Average length of stay in hospital was 3.1 ± 0.78 days. We believe Ultra fast track cardiac surgery is a safe and efficient way to conduct cardiac surgery in a highly selected group of patients. The importance of collaboration and a team based approach cannot be emphasized enough. We anticipate expanding this program within our own institution and look forward to evaluating the cost effectiveness of avoiding the ICU.

Effect of combined spinal–epidural analgesia versus epidural analgesia on labor and delivery duration

Objective To determine whether combined spinal–epidural analgesia (CSEA) can decrease the known epidural effect of lengthening delivery. Methods Between April and May 2010, 144 women undergoing childbirth in hospital with epidural pain relief were randomized to receive either low-dose epidural analgesia (LEA) or CSEA. The spinal component included 2.5 mg of bupivacaine, 25 μg of fentanyl, and 200 μg of morphine. The epidural component of the CSEA procedure was started once pain returned. The primary outcome was total labor duration measured from the time of initiation of labor analgesia to delivery. Results The difference in duration between LEA (n = 72) and CSEA (n = 72) was 5 minutes for labor ( P = 0.82), 2 minutes for delivery ( P = 0.60), and 7 minutes for total labor duration ( P = 0.75). The combined group used less levobupivacaine ( P < 0.001) and had lower sensory blockade at the dermatomal level ( P = 0.037). Women in the CSEA group had a higher incidence of pruritus ( P = 0.002) and lightheadedness ( P = 0.02) during labor; and a higher incidence of pruritus ( P = 0.002), nausea–vomiting ( P = 0.026), and drowsiness ( P = 0.003) in the postpartum period. Conclusion As compared with LEA, CSEA did not shorten the duration of labor length; however, it did reduce levobupivacaine consumption and motor weakness.

A new technique for hamstring donor site blockade in anterior cruciate ligament reconstruction

Harvesting of the hamstrings for anterior cruciate ligament reconstruction can be a significant cause of postoperative pain along the course of the stripped tendons. This can be attenuated via direct infusion of local anaesthesia.1 We have devised a technique for administering local anaesthetic along the hamstring graft harvest tract. A Kendall Argyle™ (Covidien LP, Gosport, UK) suction catheter is trimmed to length and stabilised with a femoral tunnel depth gauge (Fig 1). This device is inserted along the course of the harvested hamstring tendons; the depth gauge is removed. We inject 62.5mg of bupivacaine made up to a total volume of 50ml with normal saline 0.9% as the catheter is withdrawn. This is given as a single bolus with no subsequent top-up. Figure 1 A Kendall Argyle™ suction catheter trimmed to length and stabilised with a femoral tunnel depth gauge

The potencies for motor block after intrathecal ropivacaine and bupivacaine

Objective To determine the median effective doae (ED50) for motor block after intrathecal ropivacaine and bupivacaine. Methods Sixty ASA Ⅰ or Ⅱ patients, aged 18-64, weighing 46-75 kg, undergoing elective urological surgery under combined spinal-epidural anesthesia, were randomized into 2 groups ( n = 30each) receiving intrathecal 0.5% ropivacaine and 0.5% bupivacaine respectively. The ED50 was determined by up-down sequential allocation. The initial dose was 4 mg. Each time the dose increased/decreased by 1 mg. Efficacy was determined by the occurrence of any motor block in either lower extremity (modified Bromage scale > 0)within 5 or 10 min after the spinal injection. Results The intrathecal ED50 for motor block was 6.68 mg for ropivacaine (95% confidence interval 6.27-7.13 mg) and 4.07 mg for bupivacaine (95% confidence interval 3.56-4.47mg) . The relative motor blocking potency ratio was ropivacaine/bupivacaine 0.61. Conclusion The potency of intrathecal ropivacaine is lower than that of bupivacaine for motor block. Key words: Anesthesia, spinal; Anesthetics, local; Motor block

Continuous Block of the Articular Branches of the Femoral Nerve as a Novel Technique for Pain Control after Hip Arthroplasty

Background: We present a novel continuous block of the articular branches of the femoral nerve (ABFN) for analgesia after hip arthroplasty.Methods: In this prospective audit, twenty-five patients underwent hip arthroplasty performed by the same surgeon (MT) under spinal anaesthesia performed by the same anaesthesiologist (TH) using 10 to 15 mg of Bupivacaine 0.5%. Before February 2008, pain management after hip arthroplasty was provided solely using patient-controlled analgesia (PCA) with morphine (N = 10; PCA-group). After February 2008, block of ABFN with Ropivacaine 2% at 6 to 8 mL/h for 24 hours was additionally performed immediately after surgery (N = 15; PCA + ABFN-group) in the postoperative care unit (PACU). Pain scores were compared using a numeric pain score (NPS) at discharge from the PACU, 24 hours after surgery; total morphine consumption for the first 12 and 24 hours after surgery was compared. Data presented as means � SD and compared using Mann-Whitney rank sum test or Fisher test. P < 0.05 was considered to show a statistically significant difference.Results: Patients� demographic data were not significantly different. Pain scores were significantly lower in the PCA + ABFN-group (1 � 1.2 vs 3.5 � 2.9 in the PCA-group) at the time of discharge from the PACU, but did not differ significantly 24 hours after surgery. Morphine consumption both at 12 hours (14.7 � 7.4 mg vs 36.8 � 13.3) and 24 hours (25.7 � 14 mg vs 52.5 � 26.8) after surgery was significantly lower in the PCA + ABFN-group.Discussion: Blocking the ABFN combined with PCA morphine provides superior analgesia after hip arthroplasty than PCA morphine alone.

Clinical Comparison of 12 mg Ropivacaine and 8 mg Bupivacaine, Both with 20 µg Fentanyl, in Spinal Anaesthesia for Major Orthopaedic Surgery in Geriatric Patients

Objective: The aim of this study was to compare the haemodynamic and anaesthetic effects of 12 mg ropivacaine and 8 mg bupivacaine, both with 20 µg fentanyl, in spinal anaesthesia for major orthopaedic surgery in geriatric patients. Subjects and Methods: Sixty American Society of Anesthesiologists (ASA) II–III patients scheduled for hip arthroplasty were randomly assigned to receive an intrathecal injection of either 12 mg ropivacaine with 20 µg fentanyl (group R, aged 70 ± 7 years, range 67–89) or 8 mg hyperbaric bupivacaine with 20 µg fentanyl (group B, aged 69 ± 6 years, range 66–92). Motor and sensory block, haemodynamics and side effects were recorded. Results: Mean levels of sensory block were similar, but the onset time of sensory block in group B (2.52 ± 0.69 min) was shorter than that in group R (3.17–0.72 min); the difference was statistically significant (p < 0.01), and the number of patients who had motor Bromage scale 3 in group B (24) was greater than in group R (16). The difference was also statistically significant (p < 0.05). Systolic and diastolic arterial pressures (SAP, DAP) and heart rate (HR) decreased after the block in both groups. SAP (after the 60th and 120th min of block), DAP (all measurement times), and HR (after the 20th, 25th and 30th min of block) were lower in group B than in group R. Conclusions: The data showed that 12 mg of ropivacaine and 8 mg of bupivacaine with 20 µg fentanyl in spinal anaesthesia can provide sufficient motor and sensory block for major orthopaedic surgery in geriatric patients. However, ropivacaine caused less motor block and haemodynamic side effects than bupivacaine during the procedure.

Hipotensión arterial materna con dosis bajas de bupi y levobupivacaína intradural para cesárea más extensión epidural con salino

Epidural volume extension (EVE) with saline solution can contribute to greater cephalad spread of drugs injected into the subarachnoid space during cesarean section. We studied the incidence of material hypotension with spinal bupivacaine or levobupivacaine (L-bupivacaine) and the spread after epidural saline injection. After ethics committee approval, we randomized women scheduled for cesarean section to 4 groups to receive 5 mg of 0.25% bupivacaine with (n=51) or without (n=6) saline EVE; 5 mg of 025% L-bupivacaine (n=50); or 6 mg of 03% L-bupivacaine (n=50). All patients also received 25 microg of fentanyl per 2 mL of local hyperbaric spinal anesthetic. In all except the non-EVE group, 10 mL of saline was infused through an epidural catheter 5 minutes after anesthetic infusion. We recorded patient demographic data, procedural and anesthetic times, incision-clamping times, occurrence of hypotension, ephedrine dose required, motor and sensory blockade, requirement for rescue analgesics, and neonatal outcome. After 6 patients had been randomized to the non-EVE group, no further patients were assigned because all the women required rescue analgesics. Demographic data, duration of procedure, time between. incision and delivery, and Apgar scores were similar in all the groups. The incidence of hypotension was lower in the group receiving 5 mg of L-bupivacaine (26% vs. 52.9% in the bupivacaine 5-mg group, and 56% in the 6-mg L-bupivacaine group, P = .04). More women given 5 mg of L-bupivacaine required rescue analgesia (46%) than did those receiving 5 mg of bupivacaine (235%) or 6 mg of L-bupivacaine (28%) (P = .039). Hypotension was associated with a lower umbilical cord pH (P = .001). Ephedrine doses over 20 mg were also associated with a lower umbilical cord pH (P = .031). The incidence of hypotension was lowest in the group anesthetized with 5 mg of L-bupivacaine, but the need for rescue analgesia was greater in this group. Doses of 5 mg and 6 mg may be sufficient for cesarean section, as they provide a good level of sensory blockade.

Dose Requirement of Intrathecal Bupivacaine for Cesarean Delivery Is Similar in Obese and Normal Weight Women

The effect of BMI on the spread of intrathecal bupivacaine is controversial. This study assessed the ED95 of intrathecal bupivacaine for elective cesarean delivery in obese and normal weight women. We studied normal weight (BMI < 25 kg x m(-2)) and obese (BMI > 30 kg x m(-2)) women with singleton term pregnancies undergoing elective cesarean delivery. The study was conducted as a single blinded, up-down sequential allocation study (modified by the Narayana rule). All patients received a combined spinal-epidural anesthesia with a variable intrathecal dose of hyperbaric 0.75% bupivacaine, plus fentanyl 10 microg and morphine 100 microg. The first patient received 9 mg of bupivacaine. Supplemental anesthesia was provided through the epidural catheter if required. The primary outcome was successful analgesia, defined as a sensory block to at least T6, and no request for supplemental anesthesia. The ED95 for the satisfactory outcome was determined by a logistic model with non-log-transformed doses. Twenty-four normal weight and sixteen obese patients were enrolled. The estimated ED95 for all forty patients was 12.92 mg (95% CI: 11.49 to 34.77). The estimated ED95 for the normal weight and the obese subgroups were similar at 12.78 mg (95% CI: 10.75 to + infinity) and 11.86 mg (95%CI: 11.31 to 15.61), respectively. If single shot spinal anesthesia is used for cesarean delivery, obese and normal weight patients should receive similar doses of hyperbaric bupivacaine. Although in our study the effective dose 95% could not be precisely determined, it is possible to state that it is at least 11.49 mg.

The Median Effective Dose of Bupivacaine, Levobupivacaine, and Ropivacaine After Intrathecal Injection in Lower Limb Surgery

Intrathecal anesthesia is commonly used for lower limb surgery. Bupivacaine, levobupivacaine, and ropivacaine have all been used as intrathecal drugs, but their relative potency in this context has not been fully determined. In this study, we determined the median effective dose (ED(50)) of these three local anesthetics for intrathecal anesthesia in lower limb surgery and hence their relative potencies. Seventy-five patients scheduled for lower limb surgery under combined spinal-epidural anesthesia were randomly allocated to one of three groups receiving intrathecal bupivacaine, levobupivacaine, or ropivacaine. The dose of local anesthetic was varied using up-down sequential allocation technique. The dose for the first patient in each group was 8 mg, and the dosing increment was set at 1 mg. Subsequent doses in each group were determined by the outcome in the previous patient using success or failure of the spinal anesthesia as the primary end point. A success was recorded if a bilateral T12 sensory block to cold was attained within 20 min after intrathecal injection, and the surgery proceeded successfully until at least 50 min after the intrathecal injection without supplementary epidural injection. The ED(50) was calculated using the method of Dixon and Massey. The ED(50)s were 5.50 mg for bupivacaine (95% confidence interval [CI]: 4.90-6.10 mg), 5.68 mg for levobupivacaine (95% CI: 4.92-6.44 mg), and 8.41 mg for ropivacaine (95% CI: 7.15-9.67 mg) in intrathecal anesthesia. The relative anesthetic potency ratios are 0.97 (95% CI: 0.81-1.17) for levobupivacaine/bupivacaine, 0.65 (95% CI: 0.54-0.80) for ropivacaine/bupivacaine, and 0.68 (95% CI: 0.55-0.84) for ropivacaine/levobupivacaine. This study suggests that in intrathecal anesthesia for lower limb surgery, ropivacaine is less potent than levobupivacaine and bupivacaine, whereas the potency is similar between levobupivacaine and bupivacaine.

The potencies for motor block after intrathecal bupivacaine and levobupivacaine

Objective To determine the median effective dose (ED50) for motor block after intrathecal bupivacaine and ievobupivacaine and define their motor-blocking potency ratios. Methods In this study ED50 was determined by up-down sequential allocation. Sixty ASA Ⅰ or Ⅱ patients aged 20-60 yr with body mass index <30 kg/m2/ undergoing elective gynecological surgery under combined spinal-epidural anesthesia were randomized into 2 groups receiving intrathecal 0.5% bupivacaine and levobupivacaine respectively. The initial dose was 5 mg.Each time the dose increased/decreased by 1 mg. Efficacy was determined by the occurrence of maximum motor block (Bromage scale = 3) in both lower limbs within 20 min after the spinal injection. Results Intrathecal ED50for motor block was 6.04 mg for bupivacaine (95% CI 5.30-6.93 mg), 9.55 mg for levobupivacaine (95% CI 8.62-10.97 mg) (P <0.01). The relative motor blocking potency ratio was levobupivacaine/bupivacalne 0.63 (95 % CI 0.52-0.75). Conclusion The potency of intrathecal levobupivacaine is lower than that of bupivacaine for motor block. The ratio is 0.63. Key words: Bupivacaine ; Dose-response relationship, drug ; Anesthesia, spinal; Levobupivacaine

Factors determining the doses of local anesthetic agents in unilateral inguinal hernia repair

Today, local anesthesia is used in specialized hernia clinics in most cases. The technique for establishing local anesthesia for inguinal surgery may differ among surgeons. Few articles to date have mentioned the exact doses of local agents. This prospective study aimed to research the doses of local anesthetic agents needed in practice and determine the patient-related and other factors which affected those doses. Three hundred consecutive patients who underwent an elective unilateral inguinal hernia repair were planned to be included in the study. Lidocaine as a short-acting, medium-lasting agent and bupivacaine 0.5% as a long-acting agent were chosen. Gender, age, body mass index (BMI), side of hernia (right/left), concomitant disease, history of hernia (primary/recurrent), type of hernia (indirect/direct), Gilbert class of hernia (1-6), size of hernia (small or medium/large or massive), hernia sac content (omentum/intestine), time shift (8 am to 4 pm/later than 4 pm), duration of operation, and institutional experience (first 150 cases vs. latter 150 cases) were recorded. There were 277 male and 23 female patients. The mean age was 49.73 years (range 16-83; median 50.00). The mean volume of total anesthetic agents (lidocaine + bupivacaine) was 19.79 ml (range 5.5-40; median 19.5). The mean volumes separately were 101.79 mg for lidocaine (range 30-200; median 100) and 48.12 mg for bupivacaine (range 12.5-110; median 50). The patients were discharged after a median time of 2 h postoperatively. Univariate analysis for the total dose of the two agents showed that younger age (< or =60 vs. > or =61 years), larger size of hernia, longer duration of operation (> or =61 vs. < or =60 min), recurrent hernia, hernia sac content (omentum > intestine), and higher BMI (> or =25.1 vs. < or =25.0) were significant parameters. On the other hand, BMI, recurrent hernia, size of hernia, and omentum in the hernia sac were factors that significantly affected the mean lidocaine dose. Higher BMI and recurrent hernia also caused a higher need for bupivacaine. In addition, significantly lower doses of bupivacaine was used in older patients. The significant independent parameters in the multivariate analysis were duration of operation, sac content, and BMI for lidocaine dose, whereas the duration of operation and sac content were determinative for the sum volume of the two agents. None of the recorded parameters were found to be significant for bupivacaine dose in the logistic regression. This prospective study showed, again, the feasibility of local anesthesia in elective inguinal hernia repair in all patient groups with different characteristics. The mean and maximum doses of local anesthetic agents were well within safety limits, even in recurrent and large hernias. Younger age, large hernias, recurrent hernias, omental mass in the hernia sac, high BMI, and duration of operation might be the factors affecting local anesthetic doses. The significant independent parameters in the multivariate analysis were duration of operation, sac content, and BMI for lidocaine dose, whereas the duration of operation and sac content were determinative for the sum volume of lidocaine and bupivacaine.

Comparison of intrathecal magnesium, fentanyl, or placebo combined with bupivacaine 0.5% for parturients undergoing elective cesarean delivery

Intrathecal (i.t.) administration of magnesium has been reported to potentiate opioid antinociception in rats and humans. In this prospective, randomized, double-blind, study, we investigated the sensory, motor, and analgesic block characteristics of i.t. magnesium 50 mg compared with fentanyl 25 microg and saline when added to 0.5% bupivacaine (10 mg). Ninety ASA I or II adult patients undergoing cesarean section were randomly allocated to receive 1.0 ml of 0.9% sodium chloride in group S, 50 mg of magnesium sulfate (1.0 ml) 5% in group M, or 25 microg of fentanyl (1.0 ml) in group F following 10 mg of bupivacaine 0.5% i.t. We recorded the following: onset and duration of sensory and motor block, maximal sensory block height, the time to reach the maximal dermatomal level of sensory block, and the duration of spinal anesthesia. Magnesium did not shorten the onset time of sensory and motor blockade or prolong the duration of spinal anesthesia. The duration of sensory (P<0.032) and motor (P<0.002) blockade was significantly shorter in M and S groups than in the F group. The time to reach the maximal dermatomal level of sensory block was significantly shorter in the F group than in the S and M groups (P<0.002). In patients undergoing cesarean section with spinal anesthesia, the addition of magnesium sulfate (50 mg) i.t. to 10 mg of spinal bupivacaine (0.5%) did not shorten the onset time of sensory and motor blockade or prolong the duration of spinal anesthesia, as seen with fentanyl.

Electrogastrography during and after cesarean delivery

Although it has been generally believed that parturients have delayed gastric emptying during anesthesia, the most recent reports suggest that gastric emptying is not delayed during pregnancy except during labor. Electrical slow waves in the stomach determine the frequency and the peristaltic nature of gastric contractions. In this study we performed electrogastrography during and after elective cesarean section (CS) in an attempt to evaluate gastric motility. Sixteen American Society of Anesthesiologists physical status I or II term parturients undergoing elective CS were enrolled. Combined spinal-epidural anesthesia was initiated with 10 mg of bupivacaine plus 10 microg of fentanyl. Four-channel electrogastrography was obtained for 10 min prior to venous catheter insertion (baseline), 10 min following spinal injection of bupivacaine and fentanyl (Sp-1), 10 to 20 min following spinal injection (Sp-2), 10 min prior to the end of operation (end), and finally 10 min on the seventh postoperative day (POD 7). The mean +/- SD values for dominant frequency of electrogastrography (DF) were determined as: 1.57 +/- 0.36 cpm (baseline), 1.81 +/- 0.32 cpm (Sp-1), 2.08 +/- 0.36 cpm (Sp-2), 1.96 +/- 0.36 cpm (end), and 3.02 +/- 0.28 cpm (POD 7). The DF of Sp-1, Sp-2, and end were significantly higher than that of baseline (P < 0.05). The DF of POD 7 was significantly higher than that of baseline, Sp-1, Sp-2, and end (P < 0.01). Electrogastrography analysis suggests that the frequency of gastric contractions during CS was less than that in the postpartum period.

Is it possible to predict hypotension during onset of spinal anesthesia in elderly patients?

Study Objective To evaluate the sensitivity and specificity of various predictors of hypotension during onset of spinal anesthesia in elderly patients. Design Prospective study. Setting 32 ASA physical status I, II, and III patients, aged ≥60 years, scheduled for elective lower limb surgery with spinal anesthesia. Interventions Patients received spinal anesthesia with 10-17.5 mg of bupivacaine. No prophylactic ephedrine or fluid preloading was used. Measurements A 5-minute baseline was recorded and during onset of spinal anesthesia, hemodynamic changes were measured every 10 seconds from the radial artery pressure curve. Data collection ended when patients were ready for surgery, or if ephedrine was given to increase mean arterial pressure. Main Results 21 patients had hypotension. Baseline blood pressure variability low-frequency band power (BPV LF) >8 mmHg 2 and near-infrared spectroscopy (NIRS) reduction ≥5% had high sensitivity (0.73 and 0.90, respectively) and specificity (0.78 and 0.64, respectively), and were significantly associated with the development of hypotension. Conclusions Only NIRS and BPV LF could significantly predict hypotension among the elderly.

Results of arthroscopic adhesiolysis and manipulation in the stiff knee secondary to septic arthritis and inflammatory arthritis

The term stiV joint refers to the loss of the range of motion. It may occur as consequence of Wbrous adhesion by hemarthrosis or exudates, which may impair considerably the joint function and quality of life. The literature addressing the beneWt of arthroscopic adhesiolysis in arthroWbrosis due to septic arthritis or adhesions secondary to inXammatory arthritis is scarce [1, 2]. Although, most of the publications about arthroWbrosis are relative to trauma or surgical procedures, several medical conditions has been recognized [3–6]. To explore the beneWts of minimal invasive surgery in a series of patients who failed conservative treatment for stiV knee secondary to inXammatory or septic arthritis, we reviewed data on patients with arthritis and secondary arthroWbrosis of the knee joint, who underwent arthroscopic adhesiolysis and manipulation at our arthroscopy unit from 1991 to 2006. Of the 2,374 knee arthroscopies performed by a rheumatologist, 31 were arthroscopic adhesiolysis secondary to arthritis. The criteria for surgery were a Xexion less than 90°, and any limitation in extension. Arthroscopy was performed in the operating room under spinal or general anesthesia. Excision of Wbrotic adhesions was performed using four standard portals: suprapatellar medial and lateral, and infrapatellar medial and lateral. No posterior approaches were used. The procedure was completed with a gentle manipulation maneuvers, followed by intraarticular injection of 2 mg of morphine plus 50 mg of bupivacaine 0.25%. Postoperative pain management and rehabilitation were provided by anesthesiologist and physical therapist. The mean age of the patients was 38 (2–79) years. The average length of stay was 7.3 (0–32) days. Septic arthritis was the most common cause of stiV knee (74%), followed by gout (6.4%), juvenile idiopathic arthritis (3.2%), rheumatoid arthritis (3.2%), reactive arthritis (3.2%), and unknown arthritis (3.2%). The procedure was well tolerated and no complications were observed. Prior to arthroscopy and manipulation, extension was limited in 55% of patients, while Xexion was restricted in 90% of patients. One month after treatment, extension improved in 76% and Xexion was increased in 82% of patients. Prior to minimal invasive procedure, the mean extension was 173°, while the mean Xexion was 61°. After that, extension improved to 178° (165°–180°) and Xexion to 101°