Single shot spinal anaesthesia with hypobaric bupivacaine for hip fracture repair surgery in the elderly. Randomized,double blinded comparison of 3.75 mg vs. 7.5 mg

BackgroundArterial hypotension is the most frequent adverse effect of subarachnoid anaesthesia in the elderly sustaining a femoral proximal fracture. Decreasing the local anaesthetic dose reduces the incidence of hypotension but shortens sensory block duration that could be insufficient in some surgical procedures. Sensory block duration could be prolonged using hypobaric local anaesthetics. We evaluated whether low hypobaric bupivacaine doses were adequate for this type of surgery while maintaining the haemodynamic stability.MethodsA prospective, randomized, double blinded study was designed. Patients over 65 years old, sustaining traumatic hip fracture, were assigned to one of two groups: B0.5 group, hypobaric bupivacaine 7.5 mg 5 mg/ml (control group), and B0.25 group, hypobaric bupivacaine 3.75 mg 2.5 mg/ml (study group). After subarachnoid injection, sensory level and motor blockade degree were registered, as were blood pressure, and heart rate at basal time and at 2, 5, 10, 15, 20 and 30 min after injection. The doses of vasopressor needed were registered as well. Surgical conditions and the duration of the surgical procedure—whether rescue analgesia or anaesthesia was needed—and sensory level regression to T12, were registered as well.ResultsSixty four patients was the calculated sample size. The study was stopped in an interim analysis because an elevated number of patients in the B0.25 group needed iv rescue anaesthesia. In the analyzed cases, blood pressure was significantly lower in the B0.5 group at the 15 and 30 min measurements. Vasopressor drugs needs were similar between groups [ephedrine accumulated mean (SD) doses 11.4 (5.2) mg vs. 9.1 (2.7) mg, p = 0.045)]. Sensory block regression to T12 was faster in the B0.25 group, [(mean (SD) 68.2 (29.0) min vs. 112.8 (17.3) min in the B0.5 group, p < 0.05]. Five out of 19 patients in the B0.25 group needed intravenous anaesthesia rescue before surgery started.ConclusionLowering hypobaric bupivacaine dose to 3.75 mg in subarachnoid anaesthesia for hip fracture repair surgery in elderly patients decrease intraoperative blood pressure, but in an important number of patients intravenous anaesthesia rescue was needed and preclude recommendation.     

A new modality for improving the efficacy of intrathecal injection for cesarean section

BackgroundIntrauterine resuscitation (IUR) is to improve O2 delivery to the placenta and umbilical blood flow, for reversal of foetal hypoxia and acidosis. We evaluated whether maintaining a lateral position after an intrathecal injection of a relatively low dose of hyperbaric bupivacaine and high dose of fentanyl improving the efficacy of spinal anaesthesia, IUR and preventing hypotension during cesarean delivery.MethodsOne hundred and seventy two healthy women undergoing elective cesarean delivery were enrolled in a double blind prospective randomized study. Spinal anesthesia was conducted in the right lateral position which maintained for 6 min for all the patients participated in the study, and then the subjects were turned supine. Patients were randomly allocated to two groups: low-dose spinal bupivacaine (LD) group (n = 86) patients received 6 mg of hyperbaric bupivacaine 0.5% and 15 μg of fentanyl, high-dose spinal bupivacaine (HD) group (n = 86) patients received 10 mg of hyperbaric bupivacaine and 15 μg of fentanyl. The incidence of hypotension and nausea, ephedrine requirement, maximal block height, and Apgar score at 1 and 5 min.ResultsThe authors found significant decrease in MAP in the group that was given the high dose of bupivacaine the incidence of hypotension was 80% but the LD spinal bupivacaine group was hemodynamically stable. The lowest blood pressure, boluses of inj. ephedrine used, or nausea were more significant in the HD group than in LD group. Onset of hypotension was more rapid (8 ± 3 vs. 16 ± 6 min, P < 0.001), and the sensory block level was more cephalad in HD group than in LD group (T2 [C8–T5] vs. T4 [T1–T6], P = 0.001). Apgar scores did not differ between the groups.ConclusionMaintaining the lateral position for 6 min after an intrathecal injection of a relatively low dose of hyperbaric bupivacaine and high dose of fentanyl resulted in improving the efficacy of spinal anaesthesia, IUR by more gradual and higher cephalad sensory block, without an increase in the incidence of maternal hypotension.     

Effects of intravenous ondansetron and granisetron on hemodynamic changes and motor and sensory blockade induced by spinal anesthesia in parturients undergoing cesarean section

BackgroundSpinal anesthesia has many advantages for cesarean section parturients, but hypotension is considered the most frequent complication and can be managed by different interventions. One of these interventions is to give a serotonin receptor antagonist prior to spinal anesthesia.ObjectivesTo compare between two serotonin receptor antagonists on the hemodynamics, sensory, and motor blockade induced by intrathecal bupivacaine in parturients undergoing cesarean section.Patients and methodsSixty patients undergoing elective cesarean section under spinal anesthesia by intrathecal bupivacaine were randomly divided into three groups (20 pregnant females of ASA I–II physical status in each group). Group O received intravenous 4 mg ondansetron diluted in 10 ml normal saline and injected over 1 min, 5 min before spinal anesthesia, group G given intravenous 1 mg granisetron by the same route and group S given 10 ml normal saline. Mean arterial blood pressure, heart rate, vasopressor use, sensory, and motor blockade were assessed.ResultsDecreases in mean arterial pressure were significantly lower in group O than groups G and S with lower vasopressor use (P < 0.05), while there was significant faster sensory recovery in group G than groups O and S (P < 0.05). Actually, there were significant decrease in the incidence of nausea in groups O and G than group S (P = 0.008).ConclusionIn parturient females undergoing elective cesarean section, intravenous 4 mg ondansetron before subarachnoid block significantly decreased both the hypotension and the doses of vasopressor used, while intravenous 1 mg granisetron prior to subarachnoid block induced faster sensory recovery compared to both the ondansetron and the saline groups, with no significant differences between the later two groups.     

Low-dose bupivacaine with sufentanil prevents hypotension after spinal anesthesia for hip repair in elderly patients

BACKGROUND: Hip fracture is common in the geriatric population. Patients in this group are often at high risk for perioperative complications from concurrent diseases. Conventional spinal anesthesia can be associated with hypotension but has a better postoperative outcome compared to general anesthesia. We judged that a reduced dose of bupivacaine in combination with sufentanil could give reliable blocks with minimal hypotension. METHODS: Fifty elderly patients were randomized into two groups. The study group received spinal anesthesia as a combination of hyperbaric bupivacaine 7.5 mg and sufentanil 5 microg while the control group received hyperbaric bupivacaine 15 mg. The hemodynamic stability of the patients and the quality of the blocks were compared. RESULTS: All patients had adequate duration of reliable blocks. More control group patients than study group patients required ephedrine due to hypotension. CONCLUSION: A reduced dose of hyperbaric bupivacaine (7.5 mg) in combination with sufentanil (5 microg) provides reliable spinal anesthesia for the repair of hip fracture in aged patients with few events of hypotension and little need for vasopressor support of blood pressure.     

Efficacy of dexmedetomidine addition to bupivacaine on the quality of blind fascia iliaca compartment block in children undergoing femur fracture surgery

Efficacy of dexmedetomidine addition to bupivacaine on the quality of blind fascia iliaca compartment block in children undergoing femur fracture surgery.ObjectivesThe objectives of this study were designed to detect the effects of addition of dexmedetomidine to bupivacaine on the quality of blind fascia iliaca compartment block and its possible side effects in children undergoing fracture femur surgery.MethodsThis study was conducted on 28 children (2–6 years of age), scheduled for fracture femur surgery. Children were randomly allocated to receive either 0.25% bupivacaine 1 ml kg^?1 (B group), or 0.25% bupivacaine 1 ml kg^?1 with dexmedetomidine 2 μg kg^?1 (BD group). Anesthesia was maintained with sevoflurane 1–1.5 minimum alveolar concentration. Intraoperative sevoflurane concentration, hemodynamic, postoperative emergence delirium, sedation scores and pain scores were recorded. Duration of surgery and emergence time were recorded. Postoperative complications such as (nausea and vomiting, respiratory depression, purities, hypotension and bradycardia) were reported.ResultsCompared to the group B, patients received bupivacaine–dexmedetomidine for fascia iliaca compartment block had lower intraoperative sevoflurane concentration, higher sedation score, longer duration of postoperative analgesia, less use of rectal paracetamol for the first 24 h postoperatively and less number with postoperative agitation. No patients developed postoperative respiratory depression, purities, hypotension or bradycardia.ConclusionThe present study concluded that the combined use of bupivacaine–dexmedetomidine for fascia iliaca compartment block in children provided significant reduction of end-tidal sevoflurane concentration, remarkable hemodynamic stability, significant postoperative analgesia with lower postoperative analgesics requirements without any undesirable complications.     

Optimal intrathecal hyperbaric bupivacaine dose with opioids for cesarean delivery: a prospective double-blinded randomized trial

BackgroundSingle-shot spinal anesthesia is commonly used for cesarean delivery. Achieving adequate anesthesia throughout surgery needs to be balanced with associated complications. We investigated the optimal dose of intrathecal hyperbaric bupivacaine, co-administered with opioids, for anesthesia for cesarean delivery.MethodsThis prospective, randomized, double-blinded, dose-ranging trial included parturients scheduled to undergo cesarean delivery under spinal anesthesia. An epidural catheter was first inserted at the T11–12 vertebral interspace, followed by spinal anesthesia at the L2–3 or L3–4 vertebral interspace. Subjects were randomly assigned to one of seven doses of intrathecal hyperbaric bupivacaine 0.5% (6, 7, 8, 9, 10, 11 or 12 mg), with added 15 μg fentanyl and 75 μg morphine. Successful induction of anesthesia (success_ind) was defined as achievement of bilateral sensory loss to cold at the T6 dermatome or higher, within 10 minutes. Successful maintenance of anesthesia (success_main) was defined by no epidural supplementation within 60 minutes of intrathecal injection. The effective doses for 50% (ED₅₀) and 95% (ED₉₅) of patients were estimated using logistic regression analysis.ResultsThe ED₅₀ and ED₉₅ for success_main were 6.0 mg (95% CI: 4.5 to 7.5 mg) and 12.6 mg (95% CI: 7.9 to 17.2 mg), respectively. The incidence of respiratory discomfort and maternal satisfaction scores did not differ significantly between dose groups. Phenylephrine dose and nausea/vomiting incidence increased with increasing doses of bupivacaine.ConclusionUnder study conditions, our results suggest that 12.6 mg of intrathecal bupivacaine, administered with fentanyl and morphine, is required to achieve adequate intraoperative analgesia without the need for epidural supplemention.     

Observational study of continuous spinal anesthesia with the catheter-over-needle technique for cesarean delivery

BackgroundFew studies have assessed the efficacy and safety of continuous spinal anesthesia in obstetrics, although placement of a catheter in the intrathecal space theoretically offers advantages in these patients.MethodsNinety-two women scheduled for elective cesarean delivery using continuous spinal anesthesia with the catheter-over-needle technique (22- or 24-gauge Spinocath^®) were included in the study. The doses of local anesthetic used, hemodynamic variables, use of ephedrine and other drugs, and incidence of complications such as technical failure and postdural puncture headache (PDPH) were recorded.ResultsThe mean (±SD) dose of hyperbaric bupivacaine used was 8.2 ± 1.8 mg. The incidence of hypotension was 30% and the mean total dose of ephedrine was 4 ± 7 mg. The continuous spinal anesthetic technique failed in 18 women (20%). The overall incidence of post-dural-puncture headache was 29%; 18% of patients with post-dural-puncture headache required a blood patch.ConclusionsCompared to previous reports, the incidence of block failure and PDPH in this study was unacceptably high and therefore the risks of the technique appear to outweigh the advantages of continuous spinal anesthesia in obstetric practice.     

Hetastarch co-loading is as effective as pre-loading for the prevention of hypotension following spinal anesthesia for cesarean delivery

BackgroundPre-loading with hetastarch decreases the incidence and severity of hypotension after spinal anesthesia for cesarean delivery. However, pharmacokinetic studies with crystalloid predict that fluid loading should be more efficacious if rapidly administered immediately after induction of spinal anesthesia. The aim of this study was to compare pre- and co-loading of hetastarch for the prevention of hypotension following spinal anesthesia for cesarean delivery.MethodsForty-six healthy term parturients scheduled for cesarean delivery were randomized to receive 500 mL of 6% hetastarch intravenously, either slowly before spinal anesthesia (pre-loading) or as quickly as possible immediately after spinal anesthesia (co-loading). Systolic blood pressure was maintained at or above 90% of baseline with intravenous vasopressor boluses (ephedrine 5 mg/mL + phenylephrine 25 μg/mL). The primary outcome was the volume of vasopressor mix required. Secondary outcomes included blood pressure and heart rate changes, time to first vasopressor use, nausea or vomiting, and neonatal outcomes (umbilical artery and vein pH, Apgar scores).ResultsThe pre-loading group used 3.5 ± 2 mL (mean ± SD) of vasopressor mixture compared with 3.2 ± 3 mL in the co-loading group (P = 0.6). There were no differences in any important maternal hemodynamic or neonatal outcome values between the two study groups.ConclusionHetastarch co-loading is as effective as pre-loading for the prevention of hypotension after spinal anesthesia for cesarean delivery. Surgery need not be delayed to allow a predetermined pre-load to be administered before induction of spinal anesthesia.     

Comparison between colloid preload and crystalloid co-load in cesarean section under spinal anesthesia: a randomized controlled trial

BackgroundHypotension is a common problem during spinal anesthesia for cesarean delivery. Intravenous fluid loading is used to correct preoperative dehydration and reduce the incidence and severity of hypotension. Different fluid regimens have been studied but colloid preload and crystalloid co-load have not been compared.MethodsIn this randomized double-blind study, 210 patients scheduled for elective cesarean section under spinal anesthesia were randomly allocated to receive either 6% hydroxyethyl starch 130/0.4 500 mL before spinal anesthesia (colloid preload) or Ringer’s acetate solution 1000 mL administered rapidly starting with intrathecal injection (crystalloid co-load). Maternal hypotension (systolic blood pressure <80% of baseline or <90 mmHg) and severe hypotension (systolic blood pressure <80 mmHg) were treated with 5 and 10 mg ephedrine boluses, respectively. The primary outcome was the incidence of hypotension. Secondary outcomes included the incidence of severe hypotension, total ephedrine dose, nausea and vomiting and neonatal outcome assessed by Apgar scores and umbilical artery blood gas analysis.ResultsData analysis was performed on 205 patients; 103 in the colloid preload group and 102 in the crystalloid co-load group. There were no significant differences in the incidence of hypotension (52.4% vs. 42.2%; P=0.18) or severe hypotension (15.5% vs. 9.8%; P=0.31) between colloid preload and crystalloid co-load groups, respectively. The median [range] ephedrine dose was 5 [0–45] mg in the colloid preload group and 0 [0–35] mg in the crystalloid co-load group (P=0.065). There were no significant differences in maternal nausea or vomiting or neonatal outcomes between groups.ConclusionThe use of 1000 mL crystalloid co-load has similar effect to 500 mL colloid preload in reducing the incidence of hypotension after spinal anesthesia for elective cesarean delivery. Neither technique can totally prevent hypotension and should be combined with vasopressor use.     

Intrathecal vs intravenous magnesium as an adjuvant to bupivacaine spinal anesthesia for total hip arthroplasty

BackgroundThe aim of this study was to investigate the effect of intravenous infusion vs intrathecal magnesium sulfate during spinal anesthesia on postoperative pain, analgesic consumption, and intraoperative blood loss on patients undergoing total hip arthroplasty surgery.MethodsIn this prospective randomized controlled study, 75 adult patients, ASA physical status I and II scheduled for total hip arthroplasty, were included and randomized into three groups. Patients in Group I (control) received spinal anesthesia with hyperbaric bupivacaine and fentanyl. In Group II (IT Mg), 50 mg of magnesium sulfate was added to bupivacaine and fentanyl. In Group III (IV Mg), after induction of spinal anesthesia as in group I, a bolus dose of i.v. magnesium sulfate 40 mg kg^?1 was injected over 10 min, followed by continuous infusion of 15 mg kg^?1 h^?1 till the end of surgery. Arterial blood pressure, heart rate, electrocardiography, and O₂ saturation were continuously monitored. Onset, duration of sensory and motor block, and postoperative pain scores were assessed. Serum magnesium concentrations were checked before induction of anesthesia, immediately after surgery, at 6 h and 24 h after surgery. Total analgesic consumption and intraoperative blood loss were calculated.ResultsThere were no significant differences between the study groups in terms of onset time and maximum sensory level achieved, as well as onset and duration of motor block. Postoperative pain scores and 24 h analgesic consumption were lower in group II and III with insignificant differences between them. Intraoperative blood loss was significantly lower in group III. Postoperative Mg levels were higher in group III, without significant side effects.ConclusionsBoth i.v. infusion and intrathecal injection of Mg sulfate improved postoperative analgesia after total hip replacement. In addition, i.v. infusion of Mg sulfate reduced intraoperative blood loss.     

Ultrasound guided single injection caudal epidural anesthesia of isobaric bupivacaine with/without dexamethasone for geriatric patients undergoing total hip replacement surgery

BackgroundDexamethasone has anti-inflammatory properties that can affect postoperative analgesia when added to caudal bupivacaine.MethodsSeventy-two geriatric patients scheduled for elective total hip replacement under ultrasound guided caudal anesthesia were randomized blindly into two groups: Group BD received caudal isobaric bupivacaine 0.25% (20 ml) and dexamethasone 8 mg (2 ml) and Group BS received caudal isobaric bupivacaine 0.25% (20 ml) and normal saline (2 ml). Postoperative analgesia was assessed by recording time to first rescue analgesia and the analgesic doses (paracetamol and meperidine hydrochloride) required during the first 24 h postoperatively as a primary outcome. Secondary outcomes were the time taken to the onset of sensory analgesia at T10, time to the onset of complete motor block, VAS pain score at rest and on movement at 1, 2, 4, 6, 8, 12 and 24 h, and postoperative adverse events.ResultsGroup BD had a significantly longer time to first rescue analgesia [402 (63) vs 213 (53)] min and significantly lower doses of paracetamol [3389 (728) vs 2833 (697)] mg meperidine hydrochloride [78 (30) vs 142 (28)] mg than Group BS. VAS scores were significantly lower in Group BD than Group BS both at rest and on movement respectively at 4, 6, 8, 12 and 24 h.ConclusionAdding dexamethasone with isobaric bupivacaine caudal anesthesia prolongs the duration of postoperative analgesia and decreased postoperative analgesic requirement in geriatric patients undergoing total hip replacement surgery in comparison isobaric bupivacaine alone.     

A comparison between post-operative analgesia after intrathecal nalbuphine with bupivacaine and intrathecal fentanyl with bupivacaine after cesarean section

BackgroundAdding intrathecal opioids to intrathecal local anesthetics to decrease their doses and provide hemodynamic stability are major goals during spinal anesthesia in cesarean section. Different opioids were used to select the one with the longest duration of analgesia and the least side effects. In this study, intrathecal nalbuphine was compared with intrathecal fentanyl as an adjuvant to hyperbaric bupivacaine in cesarean section.Patients and methodsSixty female patients of ASA grades I and II presented for elective cesarean deliveries with spinal anesthesia were randomly allocated to 2 equal groups; Group F: 30 patients received intrathecal injection of 2 ml of 0.5% hyperbaric bupivacaine plus 0.5 ml fentanyl (25 μg); Group N: 30 patients received intrathecal injection of 2 ml of 0.5% hyperbaric bupivacaine plus 0.5 ml nalbuphine (0.8 mg). The onset of sensory and complete motor blockade, time of sensory blockade, duration of analgesia and motor blockade, fetal Apgar score, visual analog scale score, oxygen saturation, adverse effects and hemodynamic parameters were recorded intra-operatively and up to 4 h post-operatively. The effective analgesic time was recorded.ResultsThe onset of complete motor block was significantly more rapid in fentanyl group than in nalbuphine group. The duration of post-operative analgesia was more prolonged in nalbuphine group but the difference was insignificant. No significant difference was found between both groups as regards the duration of sensory block, motor block, duration of analgesia, fetal Apgar score, visual analog scale score, hemodynamic parameters and oxygen saturation. Adverse effects were less common in nalbuphine group but the difference was insignificant.ConclusionEither intrathecal nalbuphine 0.8 mg or intrathecal fentanyl 25 μg combined with 10 mg bupivacaine provides good intra-operative and early post-operative analgesia in cesarean section.     

Effects of intrathecal bupivacaine–fentanyl versus bupivacaine–dexmedetomidine in diabetic surgical patients

BackgroundDiabetes mellitus is the most common endocrine disorder encountered during anesthesia. Experimental researches showed that the functional μ opioid receptors in the dorsal horn of spinal cord in diabetics are either reduced or impaired in their function. This prospective study was postulated to differentiate between the effects of either opioid like fentanyl versus nonopioid like dexmedetomidine agents added to spinal bupivacaine in diabetic patients.MethodsSixty diabetic patients of either sex were submitted for elective lower limb orthopedic surgery. Patients were randomly allocated into three equal groups (each group 20 patient): bupivacaine group in which patients received 2.5 ml of hyperbaric bupivacaine 0.5% plus 0.5 mL of normal saline, bupivacaine–fentanyl group in which patients received 2.5 ml of hyperbaric bupivacaine 0.5% plus 25 μg fentanyl in 0.5 mL of normal saline and bupivacaine–dexmedetomidine group in which patients received 2.5 ml of hyperbaric bupivacaine 0.5%, plus 10 μg dexmedetomidine in 0.5 mL of normal saline. Duration and quality of sensory and motor block were assessed.ResultsThe duration of sensory and motor block as well as duration of effective analgesia was significantly longer in the bupivacaine–dexmedetomidine group as compared with both bupivacaine–fentanyl and control bupivacaine groups.ConclusionAddition of intrathecal dexmedetomidine to heavy bupivacaine 0.5% was more advantageous than fentanyl with special regard to its analgesic properties in diabetic surgical patients.     

Study of equivalence: spinal bupivacaine 15 mg versus bupivacaine 12 mg with fentanyl 15 μg for cesarean delivery

BackgroundA safe and effective intrathecal dose of bupivacaine alone for cesarean delivery has not yet been established. This study tested the hypothesis that an intrathecal dose of hyperbaric bupivacaine 15 mg would produce equivalent spinal anesthesia for cesarean delivery as the combination of hyperbaric bupivacaine 12 mg and fentanyl 15 μg.MethodsThis was a single center, double-blind, randomized clinical trial of equivalence. One hundred and thirty-eight healthy parturients scheduled for elective cesarean delivery were randomized to receive either intrathecal hyperbaric bupivacaine 15 mg (Group B) or hyperbaric bupivacaine 12 mg with fentanyl 15 μg (Group BF). Parturients where asked to describe their degree of sensation during surgery using a four-point scale 20 min after spinal injection. Secondary outcomes included the incidence of maternal side effects, maternal hemodynamics and the need for supplemental analgesia.ResultsThere was no difference in the quality of anesthesia between the two groups. Sixty-eight of 69 and 69/69 patients in Group B and Group BF, respectively had anesthesia classified as successful (RR = 1.01; 95% CI 0.85, 1.22). The only two secondary outcomes that were different between the groups were the largest change in mean arterial pressure (decrease of 40 mmHg and 34 mmHg for Group B and Group BF, respectively; P = 0.004) and the incidence of nausea (59% and 35% for Group B and Group BF, respectively; P = 0.006).ConclusionThere was no difference in the degree of sensation at 20 min between Group B and Group BF. The only significant differences between the two techniques were a higher incidence of nausea and decrease in maternal blood pressure in Group B.     

Efficacy of prophylactic use of hydrocortisone and low dose ketamine for prevention of shivering during spinal anesthesia

BackgroundSpinal anesthesia is commonly associated with shivering. The aim of this study was to compare the efficacy of i.v. hydrocortisone with i.v. low dose ketamine or placebo for prevention of shivering during spinal anesthesia.MethodIn this prospective, randomized, double-blind study, 90 female patients ASA I–II age 30–60 years old, undergoing posterior vaginal repair surgeries under spinal anesthesia with 3 ml heavy bupivacaine 0.5% (15 mg), patients were randomly allocated into one of three groups, (Group S, n = 30) (control) received saline, (Group K, n = 30) received ketamine 0.25 mg kg^?1 or (Group H, n = 30) received hydrocortisone 2 mg kg^?1, the drugs were given i.v. just after spinal anesthesia with recording of vital signs, and core temperature every 15 min intraoperative and every 10 min in recovery room. The incidence and intensity of shivering, number of patients received meperidine, sensory level, motor block grade, and side effects (hypotension, hypertension, tachycardia, nausea and vomiting, sedation and hallucinations) were also recorded.ResultsIncidence of shivering were significantly reduced in k and H groups being 20% and 23.3% respectively compared to S group (p < 0.05). Patients received meperidine to control shivering were significantly low in Groups K and H compared to group S (p < 0.05), with no difference between Groups K and H.ConclusionsThe prophylactic administration of low dose ketamine (0.25 mg kg^?1) and hydrocortisone (2 mg kg^?1) were comparable in reducing the incidence of shivering and both had significant antishivering effect compared to placebo, in female patients under spinal anesthesia for posterior vaginal repair surgeries.     

A randomized comparison of onset of anesthesia between spinal bupivacaine 5 mg with immediate epidural 2% lidocaine 5 mL and bupivacaine 10 mg for cesarean delivery

BackgroundPrevious studies using low-dose spinal anesthesia for cesarean delivery have focused on hypotension and efficacy. This study evaluated whether, using a combined spinal–epidural technique, there was a difference in onset of anesthesia for cesarean delivery between low-dose spinal with an immediate epidural local anesthetic bolus, and conventional-dose spinal anesthesia.MethodsForty healthy term nulliparous women undergoing elective cesarean delivery with a combined spinal–epidural technique were enrolled into this prospective, randomized, double-blind study. Patients were randomly allocated to the low-dose (Group L) or conventional-dose group (Group C). Patients in Group L received intrathecal isobaric bupivacaine 5 mg with sufentanil 2.5 μg followed by epidural 2% lidocaine 5 mL; patients in Group C received intrathecal isobaric bupivacaine 10 mg with sufentanil 2.5 μg followed by epidural saline 5 mL. The onset of anesthesia (defined as the time from spinal injection to a block to T6), incidence of hypotension, maximal sensory block, epidural supplementation and side effects were recorded.ResultsAll blocks reached T6 within 11 min except for one patient in Group L. There were no differences in onset of anesthesia (9.9 ± 3.2 min in Group L vs. 8.5 ± 1.2 min in Group C, P = 0.08), maximal block level and the number of patients who required epidural supplementation in both groups. Hypotension occurred in 8 patients (40%) in Group L and 15 patients (75%) in Group C (P = 0.02).ConclusionsIntrathecal bupivacaine 5 mg with immediate 2% epidural lidocaine 5 mL provided comparable onset and efficacy of anesthesia as bupivacaine 10 mg with immediate epidural normal saline 5 mL for cesarean delivery.     

Pharmacokinetics of bupivacaine after bilateral ultrasound-guided transversus abdominis plane block following cesarean delivery under spinal anesthesia

BackgroundTransversus abdominis plane block is an effective method of post-cesarean analgesia. There are no data available about plasma bupivacaine levels after this block in adults. This study aimed to assess bupivacaine pharmacokinetic parameters after ultrasound-guided transversus abdominis plane blocks following cesarean delivery under spinal anesthesia.MethodsA prospective observational study in parturients undergoing elective cesarean delivery under hyperbaric bupivacaine spinal anesthesia was conducted. After surgery, patients received bilateral transversus abdominis plane block (50 mg bupivacaine each side). Venous blood samples were collected immediately before performing the block and at 10, 20, 30, 45, 60, 90, 120, 180, 240, 720 and 1440 minutes. High performance liquid chromatography was used to measure total plasma bupivacaine concentrations. Mean bupivacaine area under the curve (AUC) was calculated from 0 to 24 hours.ResultsData were collected from 17 parturients. Mean age and body mass index were 31 ± 6 y and 30 ± 4 kg/m² respectively. Mean plasma bupivacaine concentration before the block was 171 ng/mL. Mean peak concentration was 802.36 ng/mL (range 231.8 to 3504.5 ng/mL). Mean time to peak concentration was 30 min and mean area-under-the-curve (0–24 h) was 4505.4 h.ng/mL. Mean elimination half-life was 8.75 h. Three subjects had concentrations above the quoted toxic threshold and mild symptoms suggestive of neurotoxicity were reported by two subjects, but no treatment was required.ConclusionSingle-dose bilateral transversus abdominis plane block using 100 mg of bupivacaine, after spinal anesthesia for cesarean delivery, can result in toxic plasma bupivacaine concentrations.     

A comparison of epidural magnesium and/or morphine with bupivacaine for postoperative analgesia after cesarean section

BackgroundMagnesium can potentiate the antinociceptive effect of morphine. This prospective randomized double-blinded study was undertaken to establish the analgesic effect of adding magnesium to epidural morphine during cesarean section.MethodsTwo hundred patients undergoing cesarean section under combined spinal–epidural anesthesia were recruited. After administration of intrathecal bupivacaine 10 mg, patients were randomly assigned to receive one of four epidural study solutions: 0.1% bupivacaine 10 mL (Group B); 0.1% bupivacaine 10 mL and morphine 1.5 mg (Group B+Mor); 0.1% bupivacaine 10 mL and magnesium 500 mg (Group B+Mg); or 0.1% bupivacaine 10 mL morphine 1.5 mg and magnesium 500 mg (Group B+Mor+Mg). The primary outcome was the area under the curve for visual analog scale pain scores during 36 h postoperatively. Secondary outcomes included time to the use of rescue analgesics, patient satisfaction and side effects.ResultsPatients in Group B+Mor+Mg had lower for pain scores and area under the curve pain scores both at rest and on movement, increased time for first analgesic request, and increased satisfaction score at 24 h after surgery.ConclusionAddition of magnesium 500 mg and morphine 1.5 mg to epidural 0.1% bupivacaine 10 mL reduced postoperative pain compared with addition of morphine or magnesium alone or no additive.     

O efeito de epinefrina,norepinefrina e fenilefrina no tratamento da hipotensão pós‐raquianestesia: estudo clínico comparativo

Background and objectivesLimited data are present on safety and efficiency of epinephrine for the prophylaxis and treatment of spinal‐hypotension. This study was conducted to compare the effect of epinephrine with norepinephrine and phenylephrine on the treatment of spinal‐hypotension and ephedrine requirement during cesarean delivery.MethodsOne hundred and sixty parturients with uncomplicated pregnancies undergoing elective cesarean delivery under spinal anesthesia were recruited. They were allocated randomly to receive norepinephrine 5 μg.mL^‐1 (n = 40), epinephrine 5 μg.mL^‐1 (n = 40), phenylephrine 100 μg.mL^‐1 (n = 40) or 0.9% saline infusions (n = 40) immediately after induction of spinal anesthesia. Whenever systolic blood pressure drops to less than 80% of baseline, 5 mg of iv ephedrine was administered as rescue vasopressor. The incidence of hypotension, total number of hypotension episodes, the number of patients requiring ephedrine, the mean amount of ephedrine consumption and side effects were recorded.ResultsThere was no statistically significant difference in incidence of maternal hypotension between groups. The number of patients requiring ephedrine was significantly greater in group saline than in group phenylephrine (p < 0.001). However, it was similar between phenylephrine, norepinephrine, and epinephrine groups. The mean ephedrine consumption was significantly higher in group saline than in norepinephrine, epinephrine, phenylephrine groups (p = 0.001).ConclusionThere is no statistically significant difference in incidence of hypotension and ephedrine consumption during spinal anesthesia for cesarean delivery with the use of epinephrine when compared to norepinephrine or phenylephrine. Epinephrine can be considered as an alternative agent for management of spinal hypotension.     

Dexmedetomidine decreases the required amount of bupivacaine for ultrasound-guided transversus abdominis plane block in pediatrics patients: a randomized study

BackgroundThe effect of dexmedetomidine on the potency of bupivacaine for transversus abdominis plane (TAP) block in pediatric patients has not been investigated.Study objectiveThe primary objective of this study was to assess the effectiveness of dexmedetomidine to decrease the concentration of bupivacaine needed for analgesia for ultrasound-guided TAP block in a pediatric patient undergoing hernia repair or hydrocelectomy.DesignThis is a randomized, double-blind, up-down, dose-finding study.SettingOperating room.PatientsSixty American Society of Anesthesiologists I and II patients aged 1-4 years scheduled for elective unilateral herniorrhaphy or hydrocelectomy.InterventionsPatients were randomly assigned to 1 of the 2 groups: group B (0.125% bupivacaine, 1 mL/kg) TAP block or group BD (0.125% bupivacaine plus 2 μg/kg dexmedetomidine, 1 mL/kg) TAP block.MeasurementsThe response of each child was observed for 60 seconds after skin incision and evaluated as ‘unsuccessful’ when skin incision caused a change in hemodynamic parameters (heart rate and mean blood pressure) 20% more than the preincision values. If the response was determined to be unsuccessful, the concentration of bupivacaine administrated to the next patient was increased by 0.02%. If it was successful, the concentration of bupivacaine administrated to the next patient was decreased by 0.02%.ResultsThe minimum local anesthetic concentration of bupivacaine was 0.0839% (0.0137) in the B group and 0.0550% (0.0169) in the BD group. The difference was statistically significant (t = 7.165, P = .0001). The total postoperative analgesic dosage of morphine was significantly higher in the B group (0.17 ± 0.04 mg/kg) than the BD group (0.11 ± 0.02 mg/kg, P = .001).ConclusionsThe addition of 2 μg/kg of dexmedetomidine reduced the minimum local anesthetic concentration of bupivacaine used for a TAP block and improved postoperative analgesia in children undergoing surgery for inguinal hernia repair or hydrocelectomy.