Project description:BackgroundNorepinephrine infusion decreases hypotension after spinal anesthesia during cesarean section. This study aimed to compare the efficacy of norepinephrine infusion and ephedrine bolus against post-spinal hypotension in parturients.MethodsIn this double-blinded, randomized controlled clinical trial, parturients scheduled for elective cesarean section were randomly allocated to receive norepinephrine infusion (0.05 μg·kg-1·min-1) just before spinal anesthesia continuing for 30 min or ephedrine bolus (0.15 mg/kg) just before spinal anesthesia. A rescue bolus (5 μg norepinephrine for the norepinephrine group, and 5 mg ephedrine for the ephedrine group) was administered whenever hypotension occurred. Our primary outcome was the incidence of hypotension within 30 min of spinal anesthesia administration. Secondary outcomes included maternal and neonatal outcomes 30 min after spinal block, and neonatal cerebral oxygenation 10 min after birth.ResultsIn total, 190 patients were enrolled; of these patients, 177 were included in the final analysis. Fewer patients suffered hypotension in the norepinephrine group than in the ephedrine group (29.5% vs. 44.9%, odds ratio [OR]: 0.51, 95% confidence interval [CI]: 0.28-0.95, P = 0.034). Moreover, the tachycardia frequency was lower in the norepinephrine group than in the ephedrine group (OR: 0.22, 95% CI: 0.11-0.44, P < 0.001), and patients suffered less nausea and vomiting (OR: 0.28, 95% CI: 0.11-0.70, P = 0.004). There was no difference in Apgar scores and umbilical arterial blood gas analysis between the two groups. However, neonatal cerebral regional saturations were significantly higher after birth in the norepinephrine group than in the ephedrine group (mean difference: 2.0%, 95% CI: 0.55%-3.45%, P = 0.008).ConclusionIn patients undergoing elective cesarean section with spinal anesthesia, norepinephrine infusion compared to ephedrine bolus resulted in less hypotension and tachycardia, and exhibited potential neonatal benefits.Trial registrationClinicalTrials.gov, NCT02542748; https://clinicaltrials.gov/ct2/show/record/NCT02542748.
Project description:BackgroundFluid loading is an essential component of treatment for reducing the incidence of post-spinal anesthesia hypotension and is necessary to maintain intravascular volume, perfuse tissues, and control spinal anesthesia hypotension after sympathetic blockade. We performed a randomized sequential allocation dose-finding study to compare the effects of 10 mL/kg crystalloid and 6% hydroxyethyl starch (130/0.4) co-load on the ED90 of prophylactic norepinephrine infusion for preventing post-spinal anesthesia hypotension during cesarean delivery.MethodsEighty patients were randomly allocated to receive either a 10 mL/kg crystalloid (Crystalloid Group, n = 40) or 6% hydroxyethyl starch (130/0.4) (Colloid Group, n = 40) co-load combined with prophylactic norepinephrine infusion during spinal anesthesia for cesarean delivery. The first patient received an initial prophylactic norepinephrine infusion rate of 0.025 μg/kg/min. Subsequent patients received a 0.005 μg/kg/min gradient dose of prophylactic norepinephrine. This dose was administered as a gradient based on its effectiveness for preventing post-spinal anesthesia hypotension (defined as SBP < 80% of baseline value) and determined by the up-and-down sequential allocation methodology. The primary study outcome was the ED90 of prophylactic norepinephrine infusion. Secondary outcomes included the incidence of post-spinal anesthesia hypotension, bradycardia, hypertension, Apgar scores, and umbilical artery blood gas values were also measured.ResultsThe ED90 values of prophylactic norepinephrine infusion for preventing post-spinal anesthesia hypotension during cesarean delivery were 0.063 μg (95% CI: 0.050 to 0.064) and 0.062 μg (95% CI: 0.045 to 0.064) using isotonic regression analysis, and 0.068 μg (95% CI: 0.056 to 0.353) and 0.060 μg (95% CI: 0.050 to 3.590) using probit regression analysis in the Crystalloid Group and Colloid Group, respectively. The secondary outcomes were comparable between the two groups.ConclusionThe administration of a 10 mL/kg 6% hydroxyethyl starch (130/0.4) does not provide additional benefits compared to crystalloid co-load in reducing the ED90 of prophylactic norepinephrine infusion for preventing post-spinal anesthesia hypotension during cesarean delivery.
Project description:Background: Cesarean delivery is performed under spinal anesthesia, and vasodilation is the main cause for a drop in blood pressure. The compression of the aorta and inferior vena cava by the gravid uterus is of additional clinical importance. Hypotension may occur during cesarean delivery even if prophylactic infusion of phenylephrine is practiced. We have tested if a 3 minute supine observation, can identify a subset of women with decreasing systolic arterial pressure (SAP) under spinal anesthesia. Methods: We performed a prospective observational study at Oslo University Hospital on healthy pregnant women for planned cesarean delivery. Continuous measurements of calibrated invasive SAP and estimated cardiac output were recorded for 76 women in a 3 minutes measurement with the woman in the left lateral position, followed by supine position for 3 minutes. Using functional data clustering, principal component analysis and curve smoothing, to filter way noise and reduce the dimensionality of the signal, we clustered the women into separate SAP groups. Results: We identified two significantly different groups of women during supine position; one characterized by initial drop in SAP, the other showed initial increase. After spinal anesthesia, the mean SAP curve of the women in the first group showed a drop in blood pressure, which was more rapid than for the other women. A minor difference in cardiac output was observed between the two groups of women with the mean cardiac output curve for the first group being higher. Conclusions: This work indicates that supine position affect clinically relevant cardiovascular measurements in pregnant women. A simple test may identify patients with increased risk of spinal anesthesia induced hypotension.
Project description:To determine whether crystalloid infusion just after intrathecal injection (coload) would be better than infusion before anesthesia (preload) for hypotension prophylaxis in spinal anesthesia for cesarean delivery.We searched PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and other databases for randomized controlled trials comparing coload of crystalloid with preload in parturients receiving spinal anesthesia for cesarean delivery. Primary outcome was intraoperative incidence of hypotension. Other outcomes were intraoperative need for vasopressors, hemodynamic variables, neonatal outcomes (umbilical artery pH and Apgar scores), and the incidence of maternal nausea and vomiting. We used RevMan 5.2 and STATA 12.0 for the data analyses.Ten studies with 824 cases were included. The incidence of hypotension was significantly higher in the preload group compared with the coload group (57.8% versus 47.1%, odds ratio [OR] = 1.62, 95% confidence interval [CI] = 1.11-2.37, and P = 0.01). More patients needed intraoperative vasopressors (OR = 1.71, 95% CI = 1.07-2.04, and P = 0.02) when receiving crystalloid preload. In addition, the incidence of nausea and vomiting was higher in the preload group (OR = 3.40, 95% CI = 1.88-6.16, and P < 0.0001). There were no differences in neonatal outcomes between the groups.For parturients receiving crystalloid loading in spinal anesthesia for cesarean delivery, coload strategy is superior to preload for the prevention of maternal hypotension.
Project description:BackgroundData on the best norepinephrine bolus dose for management of hypotension are limited. The aim of this study was to compare the efficacy and safety of two norepinephrine bolus doses in the rescue management of maternal hypotension during cesarean delivery.MethodsThis randomized, controlled trial included mothers scheduled for cesarean delivery with spinal anesthesia with a prophylactic norepinephrine infusion. Following spinal anaesthesia administration, a participant was considered hypotensive if systolic blood pressure was ≤80% compared to the baseline reading. Participants were allocated to receive either 6 mcg or 10 mcg norepinephrine bolus for the management of hypotensive episodes. The hemodynamic response after administration of norepinephrine bolus was recorded. The episode was considered successfully managed if systolic blood pressure returned to within 80% from the baseline reading within 2 min after norepinephrine bolus administration, and did not drop again within 6 min after the norepinephrine bolus. The primary outcome was the incidence of successful management of the first hypotensive episode. Other outcomes included systolic blood pressure, heart rate, incidence of maternal bradycardia, and reactive hypertension.ResultsOne hundred and ten mothers developed hypotensive episodes and received norepinephrine boluses for management. The number of successfully managed first hypotensive episodes was 50/57 (88%) in the 6 mcg-treated episodes and 45/53 (85%) in the 10 mcg-treated episodes (p = 0.78). Systolic blood pressure was comparable after administration of either bolus dose. Heart rate was lower after administration of 10 mcg bolus compared to 6 mcg bolus, without significant bradycardia requiring atropine administration. The incidence of reactive hypertension was comparable between both groups.ConclusionIn mothers undergoing elective cesarean delivery under prophylactic norepinephrine infusion at 0.05 mcg/kg/min, there was no advantage to the use of 10 mcg norepinephrine bolus over 6 mcg norepinephrine bolus for the rescue management of first hypotensive episode. Neither of the 2 bolus doses reached a 100% success rate. The incidences of bradycardia and reactive hypertension were comparable between both norepinephrine doses.Trial registrationAt clinicaltrial.gov registry system on January 4, 2019 Clinical trial identifier: NCT03792906.
Project description:BackgroundMaternal hypotension is the most frequent complication of spinal anesthesia for cesarean delivery, and intravenous fluid preloading is a preventive measure. We aimed to assess the efficacy of colloids versus crystalloids for preloading to reduce the incidence of spinal anesthesia-induced hypotension and vasopressor requirement in healthy parturients during elective cesarean delivery.MethodsWe searched the Cochrane Library, MEDLINE and EMBASE to identify all studies published to June, 2019, through OVID and PubMed. We included randomized controlled trials, comparing colloid preloading with crystalloid preloading in women having spinal anesthesia for cesarean delivery. Primary outcomes were the incidence of hypotension and vasopressor requirement. Secondary outcomes included nausea and/or vomiting, neonatal Apgar score, neonatal umbilical blood pH. We used standardized mean differences for expressing continuous outcomes and risk ratios for dichotomous outcomes. Random-effect model was performed to estimate the pooled risk ratios and standardized mean differences.ResultsThirty-three randomized controlled trials contributed data for this meta-analysis. Fewer women experienced hypotension in the colloid group compared with the crystalloid group (risk ratio: 0.72, 95% confidence interval: 0.63-0.82; 2566 women, 32 studies; P < .00001). The total ephedrine dose required was significantly lower with colloid preloading (standardized mean difference: -0.37, 95% CI: -0.64 to -0.09; 1472 women, 19 studies; P = .009). Colloid preloading was also associated with fewer phenylephrine requirement compared with crystalloid preloading (standardized mean difference: -0.54, 95% CI: -0.82 to -0.25; 169 women; P = .0002). The incidence of nausea and/or vomiting was significantly reduced with colloid preloading (risk ratio: 0.72, 95% CI: 0.55-0.95; 1601 women, 20 studies; P = .02). However, the incidence of 1-minute Apgar score < 7, umbilical artery pH < 7.2 and umbilical vein pH < 7.2 were not statistically different between groups.ConclusionsColloid preloading is superior to crystalloid preloading in reducing the incidence of hypotension induced by spinal anesthesia and vasopressor requirement in the healthy parturients undergoing elective cesarean delivery.The PROSPERO registration number: CRD42018096402.
Project description:BackgroundIntradialytic hypotension (IDH) is a critical pathological condition associated with all-cause mortality in patients undergoing hemodialysis (HD). However, few studies have investigated IDH-related changes in hepatic and cerebral regional tissue oxygen saturation (rSO2). This study investigated IDH-induced changes in hepatic and cerebral rSO2.MethodsHepatic and cerebral rSO2 during HD were measured using an INVOS 5100C oxygen saturation monitor, and their percentage (%) changes during the development of IDH were analyzed. Ninety-one patients undergoing HD were investigated, including twenty with IDH.ResultsIn patients with IDH, % changes in hepatic and cerebral rSO2 decreased at the onset of IDH. Additionally, the % change in hepatic rSO2 was significantly larger than that in cerebral rSO2 (p < 0.001). In patients without IDH, no significant differences were found between the % changes in hepatic and cerebral rSO2 at the time of the lowest systolic blood pressure during HD. Multivariable linear regression analysis showed that the difference between the % changes in cerebral and hepatic rSO2 was significantly associated with the development of IDH (p < 0.001) and the ultrafiltration rate (p = 0.010).ConclusionsHepatic and cerebral rSO2 significantly decreased during the development of IDH, and hepatic rSO2 was more significantly decreased than cerebral rSO2 at the onset of IDH.
Project description:AimsA systematic literature review comparing the efficacy of ephedrine and phenylephrine for the management of spinal anesthesia-induced hypotension during Cesarean sections (C-sections) was published in 2002. A number of well-designed trials with controversial results have been published afterward. Therefore, an updated meta-analysis was necessary.MethodsThe MEDLINE, EMBASE, and the Cochrane Library databases were searched (last search performed on September 26, 2011). Pooled risk ratio (RR) or standard mean difference (SMD) and their 95% confidence intervals (95% CI) were calculated for the incidence of intra-operative hypotension or umbilical blood pH values.ResultsA total number of 15 trials and 742 parturients under elective C-sections were analyzed. When used to prevent hypotension, patients receiving ephedrine and phenylephrine did not differ significantly in the incidence of hypotension (RR = 1.22; 95% CI, 0.83-1.80), umbilical arterial pH values (SMD = -0.38; 95% CI, -1.67 to 0.92) or venous pH values (SMD = -0.18; 95% CI, -0.44 to 0.07). And administration routes did not affect the incidence of hypotension and umbilical blood pH values. When used to treat hypotension, patients given ephedrine and phenylephrine had comparable incidence of intra-operative hypotension (RR = 0.79; 95% CI, 0.40-1.56), while parturients receiving phenylephrine had neonates with higher umbilical arterial pH values (SMD = -1.32; 95% CI, -2.35 to -0.30) and venous pH values (SMD = -0.79; 95% CI, -1.09 to -0.49) than those given ephedrine.ConclusionProphylactic use of ephedrine and phenylephrine were both effective in preventing maternal hypotension during C-section under spinal anesthesia; phenylephrine was superior to ephedrine in treating hypotension, evidenced by higher umbilical blood pH values.
Project description:BackgroundSpinal anesthesia is the method of choice for cesarean section and in most cases causes hypotension.ObjectiveThe aim of this study was to treat hypotension by ephedrine in order to prevent maternal and fetal complications, and also to determine the effective amount of ephedrine for reducing arterial hypertension in order to prevent its complications, including cardiac arrhythmias.MethodThis cross-sectional descriptive study was conducted on 131 patients. Mean arterial blood pressure (MAP) of the candidates for cesarean section in the supine position was measured and recorded as mean baseline blood pressure. 75 mg of lidocaine (5%) was used as spinal anesthesia, following which the average blood pressure was measured every 1 min. In the event of a decrease in the mean arterial blood pressure of at least 20% of the mean baseline blood pressure, ephedrine 0.1/mg/kg was injected intravenously and after 1 min of MAP was measured.ResultThe prevalence of hypotension was 89.30%. 25.60% of patients with hypotension had 30-34.99% reduction in MAP compared to baseline MAP. 12% patients had 40% drop in their MAP. 4 min following spinal anesthesia, the incidence of hypotension reduced by 20%. The average dose of ephedrine required to reduce the incidence of hypotension was 20.5 mg.ConclusionReduction in MAP following spinal anesthesia using lidocaine is common. Ephedrine at the dose of 20 mg is effective to reduce the incidence of perioperative hypotension.
Project description:BACKGROUND:Spinal anesthesia is a type of regional anesthesia that has been practicing for obstetric anesthesia since the beginning of the 20th century. Despite the simplicity and lower maternal mortality risk, compared to general anesthesia, spinal anesthesia is linked to different adverse effects, of which hypotension is the most common complication. The main aim of this study was to determine the incidence and associated factors of hypotension after spinal anesthesia during cesarean section. METHOD:Institution-based cross-sectional study was conducted with 410 clients. The study was conducted on cesarean section under spinal anesthesia from 5th January to 30th April 2019, at the Gandhi Memorial Hospital, Addis Ababa, Ethiopia. Both bivariable and multivariable logistic regression analysis were done on the associated factors. The level of statistical significance was represented at p<0.05. RESULTS:The incidence of hypotension among mothers who underwent a cesarean section after spinal anesthesia was 64%. Newborn weight ≥4kg (AOR = 5.373; 95%CI: (1.627-17.740)) showed an increase risk of association with hypotension. A baseline systolic blood pressure < 120mmHg (AOR = 6.293; (95%CI: 2.999-13.204)) was found to be associated with increased risk of hypotension. Sensory block height >T6 AOR = 2.230; 95%CI: (1.329-3.741), the time interval between spinal induction and skin incision > 6minutes AOR = 1.803; 95%CI: (1.044-3.114) and anesthetist experience AOR = 5.033(95%CI: 2.144-11.818) were also associated with hypotension. CONCLUSION:The identified risk factors for hypotension, after spinal anesthesia are sensory height block, weight of the baby, the time interval between spinal induction and skin incision, baseline systolic blood pressure, and anesthetist experience.