Post-spinal Anesthesia Hypotension Research Articles

Postspinal Anesthesia Hypotension in Caesarean Delivery: A Narrative Review

Postspinal Anesthesia Hypotension in Caesarean Delivery: A Narrative Review

Oral midodrine for prophylaxis against post-spinal anesthesia hypotension during hip arthroplasty in elderly population: a randomized controlled trial

BackgroundWe aimed to evaluate the efficacy of midodrine as a prophylaxis against post-spinal hypotension in elderly patients undergoing hip arthroplasty.MethodsThis randomized controlled trial included elderly patients undergoing hip arthroplasty under spinal anesthesia. Ninety minutes before the procedure, patients were randomized to receive either 5-mg midodrine or placebo (metoclopramide). After spinal anesthesia, mean arterial pressure (MAP) and heart rate were monitored every 2 min for 20 min then every 5 min until the end of the procedure. Post-spinal hypotension (MAP < 80% baseline) was treated with 10 mg ephedrine. The primary outcome was intraoperative ephedrine consumption. Secondary outcomes were the incidence of post-spinal hypotension, bradycardia, and hypertension (MAP increased by > 20% of the baseline reading).ResultsWe analyzed 29 patients in the midodrine group and 27 in the control group. The intraoperative ephedrine consumption was lower in the midodrine group than in the control group (median [quartiles]: 10 [0, 30] mg versus 30 [20, 43] mg, respectively, P-value: 0.002); and the incidence of intraoperative hypotension was lower in the midodrine group than that in the control group. The incidence of hypertension and bradycardia were comparable between the two groups.ConclusionThe use of 5 mg oral midodrine decreased the vasopressor requirements and incidence of hypotension after spinal anesthesia for hip surgery in elderly patients.Clinical trial registrationThis study was registered on September 22, 2022 at clinicaltrials.gov registry, NCT05548985, URL: https://classic.clinicaltrials.gov/ct2/show/NCT05548985.

The diagnostic accuracy of preoperative perfusion index as a predictor of postspinal anesthesia hypotension in parturients undergoing cesarean delivery: A prospective non-blinded observational study.

Spinal anesthesia is the technique of choice for elective cesarean section with a prominent side effect of postspinal anesthesia hypotension (PSH). This needs an early prediction to avoid feto-maternal complication. This study aimed to assess the diagnostic accuracy of perfusion index (PI) and inferior vena cava collapsibility index (IVCCI) in the prediction of PSH. Thirty parturients of American Society of Anesthesiologists Physical Status (ASA-PS) 1 and two undergoing cesarean delivery participated in the study. IVCCI, PI, baseline systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and heart rate (HR) were noted in the preoperative period. The fall of MBP by 20% from baseline or below 65 mm Hg was considered PSH. After spinal anesthesia, SBP, DBP, MBP, and HR were noted again for diagnosing PSH. It did not show any statistical difference when comparing the PI between the PSH and non-PSH groups in both the PSH definition groups. IVCCI was significantly higher when PSH was considered MBP <65 mm Hg (P = 0.01). However, IVCCI was found to be statistically insignificant if PSH was considered a 20% reduction in baseline MBP. The correlation matrix between IVCCI and PI showed Pearson's r-value of 0.525, indicating a substantial relationship between the two (P = 0.003). Multivariate logistic regression analysis had shown that neither IVCCI nor PI was a good predictor of PSH in parturients for both definition groups for PSH. Although there is a modest correlation between PI and IVCCI, both cannot be used to predict postspinal hypotension in parturients undergoing elective lower-segment cesarean section (LSCS).

A Double-Blinded Prospective Randomized Control Study of Preoperative Administration of Intravenous Mephentermine Vs Intramuscular Mephentermine in Preventing Post-Spinal Hypotension in Caesarean Section

Context: Mephentermine by intramuscular route prevents post-spinal anesthesia hypotension. However, the intravenous route had not been tried earlier for this prophylactic purpose. Aims: Comparing the safety and efficacy of intravenous and intramuscular routes of mephentermine in preventing maternal hypotension during cesarean section (CS). The primary objective was to compare the incidences of hypotension. Methods and Material: ASA II term parturients posted for CS were randomized into three groups. Group I received intravenous mephentermine 10 mg just before spinal and 1 ml normal saline (NS) by intramuscular route 10 minutes before spinal. Group M received intramuscular mephentermine 15 mg 10 minutes before spinal and 1 ml NS by the intravenous route just before spinal. Group C received 1 ml NS intramuscularly 10 minutes before spinal and 1 ml NS by the intravenous route just before spinal. The vital parameters, episodes of hypotension, adverse events, and neonatal parameters were assessed. Results: During midterm analysis, it was found that Group I had significantly higher adverse effects, so data collection was stopped, with a total intake of 25 patients in Group M, 22 patients in Group I, and 20 patients in Group C, respectively. The incidence of hypotension was less with the use of IM (8%) and IV (22.7%) mephentermine compared to the control group (P value: &lt;0.05). Group I had significantly more adverse events like headache (59%), chest pain (36.36%), and ST changes compared to other groups (P value: &lt;0.001). Conclusions: We conclude that the intramuscular route is better for preventing post-spinal hypotension in cesarean section with lesser maternal side effects and a better Apgar score.

Prophylactic norepinephrine combined with 6% hydroxyethyl starch (130/0.4) co-load infusion for preventing postspinal anesthesia hypotension during cesarean section: a randomized, controlled, dose-finding trial.

Colloid and/or co-load may be more effective than crystalloid for preventing postspinal anesthesia hypotension. We tested five different prophylactic norepinephrine dosages combined with colloid co-load infusion in patients receiving cesarean section and spinal anesthesia. Patients were randomly allocated to receive different prophylactic norepinephrine dosages (0 [NE 0 group], 0.025 [NE 25 group], 0.05 [NE 50 group], 0.075 [NE 75 group], or 0.1 [NE 100 group] µg/kg/min) combined with 500mL 6% hydroxyethyl starch (130/0.4) immediately following spinal anesthesia (n = 35 per group). The primary endpoint was the incidence of postspinal anesthesia hypotension (systolic blood pressure [SBP] < 80% of baseline). Secondary endpoints included severe hypotension, bradycardia, nausea or vomiting, hypertension, SBP stability control versus baseline, the 50% (effective dose, ED50) and 90% (ED90) dose effective for preventing postspinal anesthesia hypotension, Apgar scores, and umbilical cord blood gases. The incidence of postspinal anesthesia hypotension was 48.6%, 31.3%, 17.1%, 14.3%, and 5.7% in the respective groups. As the prophylactic norepinephrine dosage increased, the incidence of postspinal anesthesia hypotension declined (p < 0.001), and SBP remained stable relative to baseline (median performance error [MDPE], p < 0.001; median absolute performance error [MDAPE], p = 0.001). The ED50 and ED90 values were -0.006 (95% CI -0.046-0.013) and 0.081 (95% CI 0.063-0.119) µg/kg/min. Other endpoints were comparable across the groups. An initial prophylactic norepinephrine dosage of 0.05µg/kg/min combined with 500mL 6% hydroxyethyl starch (130/0.4) co-load infusion was optimal for preventing postspinal anesthesia hypotension during cesarean section. NCT05133817, registration date: 12 Nov, 2021.

Post-spinal hypotension management for cesarean section in low resource settings: efficiency and safety of two very low-dose boluses of norepinephrine, a randomized double-blinded controlled trial

Spinal anesthesia is the gold standard anesthetic technique for cesarean section. However, its major complication is hypotension. Norepinephrine has recently been described as an efficient and safe alternative to Phenylephrine. The aim of this study was to determine the effective target bolus of Norepinephrine to prevent and treat post-spinal anesthesia hypotension. We conducted a prospective controlled randomized study including 126 parturients scheduled for cesarean delivery under spinal anesthesia. We compared two groups that received a prophylactic bolus of either 1μg/kg or 0.5μg/kg of Norepinephrine without fluid loading. The rescue intravenous bolus of Norepinephrine was half the dose of the prophylactic bolus. The main outcomes were the percentage of decrease in systolic and mean blood pressure. The secondary outcomes included the timing of the first hypotension, duration of hypotension, number of rescue boluses, total Norepinephrine consumption, incidence of hypotension and maternal adverse effects and fetal outcomes. Our primary outcome has shown similarities between groups; delta systolic blood pressure before delivery was 19.4% in group 1µg/kg versus 20.5% in group 0.5µg/kg. Both groups were similar for all secondary outcomes, except that the higher dose of Norepinephrine resulted in more hypertension. Fetal outcomes were similar in both groups. Bolus of 0.5μg/kg followed by rescue doses of 0.25μg/kg of Norepinephrine was efficient in preventing and treating spinal anesthesia-induced hypotension. These doses may be recommended for routine use in healthy parturients.

Comparison of crystalloid and colloid co-load combined with norepinephrine prophylaxis on post-spinal anesthesia hypotension during cesarean delivery: a randomized sequential allocation dose-finding study.

Fluid 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. Eighty 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. The 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. The 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.

The Comparative Study of Intravenous Ondansetron and Dexamethasone Effects on Reducing the Incidence of Post-Spinal Anesthesia Hypotension in Elderly Pa- tients Undergoing Urologic Surgeries in Yasuj Shahid Beheshti &amp; Tehran Shahid Modarres Hospitals

The Comparative Study of Intravenous Ondansetron and Dexamethasone Effects on Reducing the Incidence of Post-Spinal Anesthesia Hypotension in Elderly Pa- tients Undergoing Urologic Surgeries in Yasuj Shahid Beheshti &amp; Tehran Shahid Modarres Hospitals

Prophylactic Fixed-Rate Phenylephrine Versus Norepinephrine Infusion in the Prevention of Post-spinal Anesthesia Hypotension During Cesarean Delivery.

Background Maternal hypotension following spinal anesthesia can be actively countered by the use of vasopressors. Prophylactic infusion of vasopressors with a rescue bolus dosing was observed to be more effective for hemodynamic stability when compared to administering a bolus dose alone. Although phenylephrine is the recommended drug to treat spinal hypotension, many recent studies have focussed on the role of norepinephrine infusions during cesarean section. In this study, we compared prophylactic fixed-rate intravenous infusions of phenylephrine and norepinephrine during cesarean delivery under spinal anesthesia and the requirement of intraoperative provider-administered rescue bolus of phenylephrine needed to overcome post-spinal anesthesia hypotension. Methodology A total of 208 patients undergoing elective cesarean section under spinal anesthesia were randomly assigned to two groups (group P and group N). Group N included 104 patients who received norepinephrine infusion at a rate of 2.5 μg/minute (0.04 μg/kg/minute), and group P included 104 patients who received phenylephrine infusion at a rate of 50 μg/minute (0.8 μg/kg/minute)to treat spinal hypotension. The primary outcome of our study was to compare the reduction in the number and total dose of intraoperative provider-administered rescue bolus of phenylephrine needed to maintain systolic blood pressure. The secondary outcome of our study was to compare the neonatal outcome using umbilical venous blood gas sampling and Apgar score at one and five minutes. Results The total number of phenylephrine rescue bolus required to treat hypotension was significantly lower in group N (p = 0.0005) compared to group P. The neonatal outcome was similar between the two groups. Conclusions Prophylactic norepinephrine infusion when compared to prophylactic phenylephrine infusion is associated with a lesser requirement of rescue phenylephrine boluses.

Preoperative assessment of inferior vena cava collapsibility index by ultrasound is not a reliable predictor of post-spinal anesthesia hypotension

BackgroundPost-spinal anesthesia hypotension is of common occurrence, and it hampers tissue perfusion. Several preoperative factors determine patient susceptibility to hypotension. This study aimed to assess the effectiveness of the Inferior Vena Cava Collapsibility Index (IVCCI) for predicting intraoperative hypotension. MethodsOne hundred twenty-nine adult patients who were scheduled for elective surgical procedures after administration of spinal (intrathecal) anesthesia were included in the study. Ultrasound evaluation of the Inferior Vena Cava (IVC) was done in the preoperative area, and the patients were shifted to the Operating Room (OR) for spinal anesthesia. An independent observer recorded the change in blood pressure after spinal anesthesia inside the OR. ResultsTwenty-five patients developed hypotension (19.37%). Baseline systolic blood pressure and mean blood pressures were statistically higher in those patients who developed hypotension (p = 0.001). The logistic regression analysis for IVCCI and the incidence of hypotension showed r2 of 0.025. Receiver Operating Characteristic (ROC) curve analysis demonstrated the Area Under the Curve (AUC) of 0.467 (95% Confidence Interval, 0.338 to 0.597; p = 0.615). ConclusionsPreoperative evaluation of IVCCI is not a good predictor for the occurrence of hypotension after spinal anesthesia.

Pre-operative Ultrasonographic Evaluation of the Internal Jugular Vein Collapsibility Index and Inferior Vena Cava Collapsibility Index to Predict Post Spinal Hypotension in Pregnant Women Undergoing Caesarean Section.

BackgroundPost spinal anesthesia hypotension (PSAH) is frequently encountered in anesthetic practice, especially during cesarean section. Ultrasound is a safe and easy technique for hemodynamic monitoring.ObjectivesThis study was conducted to assess the efficacy of pre-operative inferior vena cava collapsibility index (IVCCI) and internal jugular vein collapsibility index (IJVCI) in predicting PSAH.MethodsThis cross-sectional blinded study included 55 pregnant females prepared for elective cesarean section. They were divided into two groups based on the incidence of PSAH: (1) cases with PSAH (26 cases); and (2) cases without PSAH (29 cases). All the cases underwent ultrasound-guided measurement of IVCCI and IJVCI. The efficacy of these parameters was assessed in predicting PSAH.ResultsCases in both groups expressed non-significant differences regarding demographic data. However, IVCCI had mean values of 38.27 and 23.97%, while IJVCCI had mean values of 46.50 and 33.41%, respectively, in cases with and without PSAH. For IVCCI, using a cut-off point of 33% had sensitivity and specificity (84.6 and 93.1%, respectively) for predicting PSAH, with a diagnostic accuracy of 89.1%. IJVCI had sensitivity and specificity of 84.6 and 82.8%, respectively, for predicting the same complication using a cut-off value of 38.5%.ConclusionIVCCI and IJVCI are efficacious and reliable tools in predicting PSAH in pregnant ladies undergoing cesarean section, with a slight superiority for IVCCI regarding specificity and accuracy.

Inferior Vena Cava Collapsibility Index Can Predict Hypotension and Guide Fluid Management After Spinal Anesthesia

PurposeWe hypothesized that inferior vena cava collapsibility index (IVCCI)-guided fluid management would reduce the incidence of postspinal anesthesia hypotension in patients undergoing non-cardiovascular, non-obstetric surgery.MethodsA receiver operating characteristic (ROC) curve was used to determine the diagnostic value of IVCCI for predicting hypotension after induction of spinal anesthesia and calculate the cut-off value. Based on the cut-off variation value, the following prospective randomized controlled trial aimed to compare the incidence of postspinal anesthesia hypotension between the IVCCI-guided fluid administration group and the standard fluid administration group. Secondary outcomes included the rate of vasoactive drug administration, the amount of fluid administered, and the incidence of nausea and vomiting.ResultsROC curve analysis revealed that IVCCI had a sensitivity of 83.9%, a specificity of 76.3%, and a positive predictive value of 84% for predicting postspinal anesthesia hypotension at a cut-off point of >42%. The area under the curve (AUC) was 0.834 (95% confidence interval: 0.740–0.904). According to the cut-off variation value of 42%, the IVCCI-guided group exhibited a lower incidence of hypotension than the standard group [9 (15.3%) vs. 20 (31.7%), P = 0.032]. Total fluid administered was lower in the IVCCI-guided group than in the standard group [330 (0–560) mL vs. 345 (285–670) mL, P = 0.030].ConclusionsPrespinal ultrasound scanning of the IVCCI provides a reliable predictor of hypotension following spinal anesthesia at a cut-off point of >42%. IVCCI-guided fluid management before spinal anesthesia can reduce the incidence of hypotension following spinal anesthesia.

Distribution of cesarean delivery by Robson classification and predictors of postspinal anesthesia hypotension in Windhoek referral hospitals: A cross-sectional study.

There are concerns that high cesarean section (CS) rates are driven by nonmedical indications and unmitigated maternal hypotension following spinal anesthesia (SA) has materno fetal effects. Our objective was to investigate CS rates using Robson classification, identify patient groups for focused intervention as well as assess the incidence and predictors of maternal hypotension following SA for cesarean delivery. A cross sectional design was employed over 3 months (February-April, 2019). Data about total deliveries (vaginal and operative) were obtained from the hospital medical records. For parturients who had CS, variables which covered maternal characteristics, conduct of anesthesia, and the index pregnancy according to Robson classification system were entered into a proforma designed for the study. The total deliveries were 3031, of which 556 were CSs, giving a CS rate of 18.3%. Twenty one nonconsenting parturients were excluded, so 535 responded. Robson groups 5, 10, and 1 combined contributed 75% [401/535] to the overall CS. Two or more previous CS, 29.7% [159/535], was the main indication for performing CS, followed by maternal request 12.9% [69/535]. The incidence of maternal hypotension was 62.6% (293/468); the independent predictors were elective CS and having comorbidities. We found a low CS rate and Robson groups 5, 10, and 1 were the major contributors - previous CS (≥2) and maternal request were the predominant indications for performing CS. The independent predictors of SA induced hypotension were presence of comorbidities and elective CS.

Comparison of Norepinephrine and Ephedrine Boluses in the Control of Spinal Anesthesia-Induced Hypotension during Cesarean Section: A Randomized Controlled Trial

Introduction: Phenylephrine and ephedrine are the first-line vasopressors used in obstetric anesthesia to manage maternal hypotension, but phenylephrine is sometimes associated with maternal cardiac depression, limiting its use among mothers with cardiac comorbidities. The use of ephedrine is generally associated with maternal tachycardia along with a decrease in fetal pH. Norepinephrine is another vasopressor that has recently been introduced in obstetrical anesthesia and has attracted increasing attention as a feasible substitute for these two molecules in this context. The objective of our study is to compare two vasopressor agents (norepinephrine vs ephedrine) dedicated to the treatement of post-spinal anesthesia hypotension, and then to define the place of norepinephrine in the pharmacopoeia of the latter. Materials and Method: A Randomized controlled study of 80 ASAI parturient randomized to receive either 8µg boluses of norepinephrine (NG)or 6mg boluses of ephedrine(EG).The criteria for judgment included the occurrence of tachycardia, the maintenance of blood pressure, and the number of boluses required, as well as the clinical condition of the neonate. Results: The incidence of tachycardia (HR&gt;80bpm) was lower in NG (18%) compared to that in EG(67.6%) p=0.0001, crude Odds Ratio 14.968 95% CI] 4.924, 45.505[ . Six in NG (12%) and eight in EG (26.7%) patients experienced nausea, OR 2.667 95% CI] 0.823-8.641[while only three in NG (6%), and four EG (13%) patients experienced vomiting p=0.41 OR:2.41 CI 95% ]0.501-11.605[. Blood pressure was stablefor both groups but with a superiority of norepinephrine which allowed more marked maintenance: 75% to 112% of the initial systolic value in NG versus 72% to 100% in EG), the difference was highly significant p&lt;0.0001. No significant differences in neonatal outcomes were observed. Conclusion: Norepinephrine can maintain blood pressure more effectively than ephedrine with less incidence of tachycardia .............

Regional tissue oxygen saturation as a predictor of post-spinal anesthesia hypotension for cesarean delivery.

Regional tissue oxygen saturation as a predictor of post-spinal anesthesia hypotension for cesarean delivery.

Prophylactic norepinephrine infusion for postspinal anesthesia hypotension in patients undergoing cesarean section: A randomized, controlled, dose-finding trial.

Prophylactic norepinephrine infusion effectively lowers the incidence of postspinal anesthesia hypotension. The optimal prophylactic dose of norepinephrine remains undefined. The purpose of this study was to investigate the optimal prophylactic dose of norepinephrine to prevent postspinal anesthesia hypotension in patients undergoing cesarean section. Prospective, double-blind, randomized, controlled, dose-finding trial. Operating room from March 2020 to June 2020. Ninety nine primipara or multipara women 18 - 40 years of age, singleton pregnancy ≥ 37 weeks, American Society of Anesthesiologists' physical status 1 or 2, scheduled for elective cesarean section under spinal anesthesia were included in this study. Patients were randomly assigned into groups to receive normal saline (NS) or one of four different prophylactic doses (0.025 [NE25], 0.05 [NE50], 0.075 [NE75], and 0.1 [NE100] ug/kg/min) of norepinephrine. The primary end point was the incidence of postspinal anesthesia hypotension (systolic blood pressure [SBP] < 80% of baseline) within 15 min after spinal anesthesia. Secondary outcomes included the overall stability of SBP control versus baseline (median performance error [MDPE] and median absolute performance error [MDAPE]), the dose that would be effective in preventing postspinal anesthesia hypotension in 50% (effective dose, ED 50) and 90% (ED90) of patients, other adverse events (bradycardia, nausea, vomiting, hypertension, and the total additional bolus of norepinephrine and atropine), and neonatal outcomes (blood gas values and Apgar scores). The incidence of postspinal anesthesia hypotension in NS, NE25, NE50, NE75, and NE100 groups was 68.42% (13/19), 40.00% (8/20), 20.00% (4/20), 15.00% (3/20), and 10.00% (2/20), respectively. With increasing prophylactic doses of norepinephrine, the incidence of postspinal anesthesia hypotension decreased (p < 0.001), SBP was maintained closer to the baseline (MDPE, p < 0.001; MDAPE, p = 0.001), and the total additional bolus of norepinephrine decreased (p < 0.001). The ED50 and ED90 values of norepinephrine were 0.016 (95% CI: -0.014 - 0.033) and 0.088 (95% CI: 0.068 - 0.133) ug/kg/min, respectively. Other adverse effects, neonatal outcomes, and the total additional bolus of atropine did not differ among the five groups. A prophylactic dose of 0.05 or 0.075 μg/kg/min norepinephrine prevents postspinal anesthesia hypotension in patients undergoing cesarean section.

Use of Inferior Venacaval Collapsibility Index in Spinal Anesthesia during Orthopedic Surgeries.

Background:Volume deficit is one of the predictors of hypotension. Inferior venacaval collapsibility index (IVCCI) can detect volume deficit and aids volume resuscitation in patients of intensive care unit.Aims:The primary aim was to compare the incidence of postspinal anesthesia hypotension (PSAH) in IVCCI measured and nonmeasured groups. The secondary aim was to determine IVCCI association with PSAH within IVCCI measured group in spite of fluid bolus.Settings and Designs:This was a prospective, randomized, controlled, single-blinded study.Methodology:One hundred patients posted for orthopedic surgery under spinal anesthesia (SA) were randomly divided as IVCCI measured (CI) and non-IVCCI measured (NCI) groups before SA. If IVCCI was more than 40% fluid bolus was given. Intraoperative hemodynamics was monitored. PSAH managed with fluids and vasopressors which were noted. Data collected were analyzed with unpaired t-test, Z-test, logistic regression test, and Pearson's correlation.Results:PSAH incidence was 18% in group (CI) whereas 38% in group (NCI), and the difference was statistically significant. Vasopressors given were higher in group NCI. Perioperative fluids were more in group CI, but the intraoperative fluids were more in group NCI. There was no statistically significant association between PSAH after fluid preloading and IVCCI within the IVCCI measured group.Conclusion:Prespinal anesthesia evaluation of IVCCI to optimize fluid therapy can reduce the incidence of PSAH in orthopedic surgeries and the vasopressor requirement, and hence, the association of IVCCI of more than 40% with PSAH.

Role of left uterine placement in maternal care bundle for the prevention of spinal anesthesia-induced hypotension in cesarean section

Background Hypotension is the most common serious scenario in patients undergoing cesarean sections under spinal anesthesia. Care bundles have been employed using a set of three to five approaches with the aim to prevent and manage hypotension after spinal anesthesia. This study was conducted to determine the effectiveness of left uterine placement in maternal care bundle for the prevention of spinal anesthesia-induced hypotension in cesarean section.Patients and methods A total of 100 parturients age 25–35 years with American Society of Anesthesia grades I and II, undergoing elective cesarean section under spinal anesthesia, were assigned into two equal groups at random: group A and group B (each group n=50). Both groups were subjected to a bundle of care using 4-mg ondansetron diluted in 10-ml normal saline given slowly intravenous for 5 min before the induction of spinal anesthesia, and spinal anesthesia was initiated using hyperbaric bupivacaine with a constant dose (10 mg), and administration of intravenous ephedrine 9 mg was done after spinal anesthesia had been cited. Group A was subjected to additional parameter in the care bundle, including patient’s suitable position with left displacement of the pregnant uterus. Mean arterial blood pressure (MABP) and heart rate (HR) were recorded every 5 min for 45 min after spinal anesthesia. The total ephedrine and atropine requirements were also determined.Results Both groups showed a nonsignificant difference of the MABP and HR at the baseline measurement values. Follow-up of MABP and HR values every 5 min for 45 min after the onset of spinal anesthesia showed a statistically significant decrease in both groups. Overall consumption of ephedrine and atropine showed statistically significant decrease in group A compared with group B (P<0.001 and 0.01, respectively). By comparing the effect size between both groups using Cohen’s d test regarding MABP, HR measurements, and total dose of ephedrine and atropine, we found that it had a small effect size.Conclusion The application of left uterine placement is an important and effective parameter in a maternal care bundle for decreasing the incidence of postspinal anesthesia hypotension in parturients undergoing elective cesarean section.

Observation of hemodynamic parameters using a non-invasive cardiac output monitor system to identify predictive indicators for post-spinal anesthesia hypotension in parturients undergoing cesarean section.

The administration of high-level spinal anesthesia for cesarean section may lead to significant hemodynamic changes. Bioreactance-based non-invasive cardiac output monitoring (NICOM™) provides an accurate monitoring system for parturients under spinal anesthesia. The present study hypothesized that baseline hemodynamic parameters obtained via the NICOM™ system could serve as predictive indicators for post-spinal anesthesia hypotension. Therefore, 80 full-term parturients with singleton pregnancies who underwent scheduled cesarean section were enrolled and allocated to either a supine position group or a 15˚ left tilt group. All parturients received standard pre-hydration with 750 ml of 0.9% saline. Baseline cardiac output index (CI), total peripheral resistance index (TPRI) and stroke volume (SV) were recorded using the NICOM™ system. Subsequently, spinal anesthesia with 2.4 ml of 0.5% hyperbaric bupivacaine, 10 µg of fentanyl and 0.2 mg of morphine was administered. Receiver operating characteristic (ROC) curves and multivariate logistic regression were used to analyze the data. A total of 40 parturients (51.9%) developed hypotension. The areas under the ROC curves were 0.666, 0.594 and 0.622 for the CI, TPRI and SV, respectively. The optimal cut-off value of the CI in predicting hypotension was 3.68 l/min/m2 (ROC, sensitivity=85.0%, specificity=48.6%). Furthermore, CI was considered as an independent factor for post-spinal anesthesia hypotension. In conclusion, the baseline CI obtained via the bioreactance-based NICOM™ system may serve as a predictor of post-spinal anesthesia hypotension in parturients regardless of patient position.

Norepinephrine prophylaxis for postspinal anesthesia hypotension in parturient undergoing cesarean section: a randomized, controlled trial.

To investigate the efficacy and safety of prophylactic infusion of norepinephrine (NE) versus normal saline in patients undergoing cesarean section. Patients (n = 97) were randomized to receive a bolus of NE (6μg) immediately following spinal anesthesia with maintenance NE (0.05μg/kg/min IV) or normal saline (n = 98). The primary endpoint was the incidence of postspinal anesthesia hypotension [systolic blood pressure (SBP) < 80% of baseline] at 1-20min following spinal anesthesia. Secondary outcomes were the overall stability of SBP control versus baseline, inferior vena cava collapsibility index (IVC-CI), other adverse events (bradycardia, nausea, vomiting, and hypertension), and neonatal outcomes (blood gas values and Apgar scores). The rates of postspinal anesthesia hypotension and severe postspinal anesthesia hypotension (SBP < 60% of the baseline) were significantly lower in the NE group (17.5% vs. 62.2%, p < 0.001; 7.2% vs. 17.4%, p = 0.031). In the NE group, SBP remained more stable and closer to baseline (p < 0.001), and IVC-CI values were lower 5min after spinal anesthesia and 5min after fetal delivery (p = 0.045; p < 0.001, respectively). Other adverse effects and neonatal outcomes were not different between the two groups. Prophylactic NE infusion effectively lowers the incidence of postspinal anesthesia hypotension and does not increase other adverse events in patients or neonates.