Hypotension In Cesarean Delivery Research Articles

Impact of Sub-Anesthetic Dose of Ketamine on Post Spinal Hypotension in Cesarean Delivery

Abstract Background Spinal anesthesia is the commonest technique used in Cesarean Section (CS) and most frequently associated with maternal hypotension, for whicha lot of techniques have been described to prevent but an effective method is yet to be found. Objectives The aim was to study the effect of using a sub-anesthetic dose of ketamine to prevent post-spinal hypotension in CS delivery. Methods This double-blinded randomized controlled study was conducted on 60 participating parturients who were ASA І, П term pregnant. All the parturients received spinal anesthesia. The parturients were then randomly divided into two equal groups (n = 30 in each); ketamine group received a sub- anesthetic dose of ketamine of 0.5 mg/kg IV bolus in 3 ml saline and control group received the same volume of normal saline IV bolus. Heart Rate (HR) and Mean Arterial blood Pressure (MAP) were recorded at baseline (5 minutes prior to the intrathecal injection), at 5, 10, 15 and 20 minutes after the injection and then every 15 minutes till the end of the operation. Incidences of hypotension and severe hypotension were recorded. The total dose of ephedrine was recorded. Modified Ramsay sedation score was recorded at baseline then 5, 10, 15, 30, 45 minutes after injection and then at the end of the operation. Results The study revealed that ketamine didn’t prevent hypotension, it only delayed it for 10 min compared to control group 5 min. Also, observed that total ephidren dose significantly decreased in ketamine group compared to control group. And sedation scores in the first 30 min were higher in ketamine group. HR wasn’t affected. No changes in APGAR score were noticed between the two groups. No side effects from ketamine except for nystagmus. Conclusion This study concluded that the use of intravenous ketamine in low dose (0.5mg/kg) doesn’t prevent postspinal hypotension but it only decreases ephidren requirements.

Postspinal Anesthesia Hypotension in Caesarean Delivery: A Narrative Review.

Anesthesiologists frequently deal with spinal hypotension when administering spinal anesthesia (SA) for a Caesarean section (C-section). The physiological changes that occur during pregnancy necessitate modifications to anesthesia and analgesia procedures to provide safe and efficient care for the expectant patient. It is believed that giving the patient SA during a C-section will increase their degree of comfort and pain management both during and after the surgical process. It is less expensive, easier to give, and delivers a consistent anesthetic onset, early ambulation, and the start of breastfeeding.As C-section is a very common operation performed in every healthcare unit, dealing with postspinal hypotension is a daily situation faced by anesthetists with variable levels of experience. However, understanding and addressing hypotension induced by SA is crucial as it affects the mother and the fetus negatively. This review aims to contribute to enhancing patient care and safety in the context of C-sections by identifying hypotension timely and managing it effectively. It is advised to healthcare workers to leverage the insights from the review to improve patient outcomes in routine practice.

Prevention of post-spinal anaesthesia hypotension in caesarean delivery using delayed supine positioning - A randomised controlled trial.

Maternal hypotension is a common and dangerous consequence after a subarachnoid block for a caesarean section. Combining pharmacological methods such as norepinephrine infusion, ondansetron and non-pharmacological methods in delayed supine positioning better impacts the maternal haemodynamic profile. The present study assessed the benefits and adverse effects of combining pharmacological and non-pharmacological methods in hypotension prophylaxis. This randomised controlled trial was conducted at Cairo University Hospital's obstetric theatre from January to October 2020. The study included 85 parturients who were randomised to two groups. Group Sitting was left seated for 2 min after injection, and Group Control was made to lie down in the supine position immediately after the subarachnoid block. Both groups received prophylactic intravenous norepinephrine infusion, in addition to an ondansetron bolus, before surgery. Patients' systolic blood pressure (SBP) from intrathecal injection until delivery of the foetus, was documented. The Sitting group's SBP (122 (14) mmHg) till delivery was statistically higher than the Control group's readings (114 (10) mmHg) (P = 0.004). The Sitting group's intraoperative SBP values were often greater than the Control group values. In addition, the Sitting group had a reduced hypotension incidence and a lower rate of ephedrine use than the other group, but bradycardia incidence was comparable between both groups. In elective caesarean delivery, combining pharmacological and non-pharmacological methods achieve better results regarding maternal hypotension, vasopressor consumption, nausea and vomiting, and foetal outcomes.

Oxytocin infusion for maintenance of uterine tone under prophylactic phenylephrine infusion for prevention of post-spinal hypotension in cesarean delivery: a prospective randomised double-blinded dose-finding study

BackgroundPrior studies have shown that, when administered as an intravenous bolus to prevent uterine atony, prophylactic phenylephrine infusion increased the dose requirement of oxytocin and second-line uterotonics. For the prevention of uterine atony, oxytocin should be delivered by continuous infusion. Here, we aimed to determine the ED50 and ED90 parameters (the effective doses for 50 and 90% patients without uterine atony) of oxytocin for co-infusion with prophylactic phenylephrine during cesarean delivery.MethodsIn this prospective randomized double-blinded dose-finding study, one hundred patients were divided into four groups to receive 2.5, 5.0, 7.5, or 10 IU/h oxytocin infusion, after the umbilical cord was clamped during the study period. The uterine tone was evaluated and defined as either adequate or inadequate. Probit regression analysis was applied to calculate the ED50 and ED90 of oxytocin infusion. Uterine tone, the percentage of patients who needed additional oxytocin bolus, second-line uterotonics, side effects, estimated blood loss, and neonatal outcomes were monitored.ResultsThe estimated ED50 and ED90 values of the oxytocin infusion doses for the prevention of uterine atony were 1.9 IU/h (95% CI -4.6-3.8) IU/h and 9.3 IU/h (95% CI 7.3–16.2) IU/h, respectively. Across groups, there was a significant linear trend between the infusion dose and the percentage of patients who required additional oxytocin (p-value = 0.002). No differences were observed in the incidence of side effects and neonatal outcomes.ConclusionUnder the conditions of this study, the ED90 of oxytocin infusion for the prevention of uterine atony was 9.3 IU/h, which is higher than the current recommendation. This finding is helpful for clinical practice, because of the routine use of phenylephrine in cesarean delivery. Further studies are needed to determine the appropriate initial bolus of oxytocin after neonatal delivery.Trial registrationThe study was registered on the Chinese Clinical Trial Register (register no. ChiCTR2200059556).

The Overview of Shivering and Blood Preassure Occurance Before and After Liquid Co-Loading on Sectio Caesarea Patients

Background: The incidence of shivering and hypotension in cesarean delivery is frequent. The incidence of shivering due to spinal anesthesia is reported to reach 50-65%. While hypotension after spinal anesthesia in sectio caesarea can occur up to 80%. Fluid coloading is done to reduce shivering and overcome hypotension in mothers who have cesarean delivery. Purpose: the study was to determine the description of the incidence of shivering and blood pressure before and after fluid coloading in sectio caesarea patients at RSI Banjarnegara. Method: The design of this study was descriptive with a cross-sectional approach. The study was conducted in June 2023. The sample of this study was 44 respondents with purposive sampling techniques. Results: The showed that the incidence of shivering was experienced by many respondents after being given coloading, which was 37 respondents (84.1%) compared to before coloading there were only 5 respondents (11.4%). While in blood pressure, before coloading the majority experienced hypotension events as many as 37 respondents (84.1%) and after coloading most of the blood pressure became normal as many as 41 respondents (93.2%). Conclusions: It can be concluded that fluid coloading is less effective for shivering treatment, but fluid coloading is effective in maintaining blood pressure in mothers undergoing sectio caesarea after spinal anesthesia.

Comparison of Crystalloid Preloading and Coloading for Prevention of Spinal-induced Hypotension in Cesarean Delivery: A Randomized Controlled Trial at a Tertiary Facility in Ghana

BACKGROUND: Spinal anesthesia is the recommended technique for cesarean section. It is easy to perform and provides a reliable, safe, effective, and fast sensory and motor block of high quality. Hypotension, which can be deleterious to both mother and baby, is however a common side effect. Preloading has not been shown to consistently prevent spinal-induced hypotension. AIM: The aim of this study was to compare coloading with preloading using crystalloids for preventing spinal anesthesia-induced hypotension in parturients undergoing scheduled cesarean delivery. MATERIALS AND METHODS: A single-blinded, randomized, and controlled study was conducted on 88 patients at term scheduled for elective cesarean delivery under spinal anesthesia at the Korle-Bu Teaching Hospital. Parturients were randomly assigned to receive a preload of 12.5 mL/kg of Ringer’s Lactate (Group P) before the spinal anesthetic or a coload of 12.5 mL/kg of Ringers Lactate (Group C) at the time of the spinal procedure. Blood pressure, heart rate, incidence and timing of nausea and vomiting, and amount and frequency of vasopressor used were recorded for the first 10 minutes post-spinal anesthesia. Neonatal Apgar scores were determined at 1 and 5 minutes after birth. RESULTS: The two groups were comparable with respect to age, weight, height, gestational age, ASA classification, baseline hemodynamic measurements, time to onset of hypotension, and time to delivery of baby post-spinal anesthesia. Post-spinal anesthesia changes in the heart rate, systolic blood pressure and mean arterial blood pressure were also comparable between the two groups. None of the patients in both groups experienced nausea or vomiting without hypotension. Although the cumulative dose of ephedrine to treat hypotension in the preload group was higher compared to the coload group, the difference was not statistically significant (16.3 vs. 12.4; p-value = 0.110). CONCLUSION: Preloading and coloading with 12.5 mL/kg of Ringer’s Lactate are comparable but neither is effective alone for preventing spinal-induced hypotension in the obstetric population. A vasopressor regimen is required to improve efficacy of the fluid load for preventing spinal-induced hypotension.

Incidence of bradycardia during noradrenaline or phenylephrine bolus treatment of postspinal hypotension in cesarean delivery: A randomized double-blinded controlled trial.

The treatment of choice for spinal anesthesia-induced hypotension during cesarean section is phenylephrine. As this vasopressor can cause reflex bradycardia, noradrenaline is a suggested alternative. This randomized double-blinded controlled trial included 76 parturients undergoing elective cesarean delivery under spinal anesthesia. Women received noradrenaline in bolus doses of 5mcg or phenylephrine in bolus doses of 100 mcg. These drugs were used intermittently and therapeutically to maintain systolic blood pressure ≥ 90% of its baseline value. The primary study outcome was bradycardia incidence (<60 bpm) with intermittent bolus administration of these drugs. Secondary outcomes included extreme bradycardia (<40 bpm), number of bradycardia episodes, hypertension (systolic blood pressure > 120% of baseline value), and hypotension (systolic blood pressure < 90% of baseline value and requiring vasopressor use). Neonatal outcomes per the Apgar scale and umbilical cord blood gas analysis were also compared. The incidence of bradycardia in both groups (51.4% and 70.3%, respectively; p=0.16) were not significantly different. No neonates had umbilical vein or artery pH values below 7.20. The noradrenaline group required more boluses than phenylephrine group (8 vs. 5; p=0.01). There was no significant intergroup difference in any of the other secondary outcomes. When administered in intermittent bolus doses for the treatment of postspinal hypotension in elective cesarean delivery, noradrenaline, and phenylephrine have a similar incidence of bradycardia. When treating hypotension related to spinal anesthesia in obstetric cases, strong vasopressors are commonly administered, thought these can also have side effects. This trial assessed bradycardia after bolus administration of noradrenaline or phenylephrine, and found no difference in risk for clinically meaningful bradycardia.

A Randomized Double-Blinded Dose-dependent Study of Metaraminol for Preventing Spinal-Induced Hypotension in Caesarean Delivery.

Purpose: Prophylactic infusion of a vasopressor is preferred as a rational choice in clinical practice in Cesarean delivery. Metaraminol is one of most common vasopressors used in obstetric clinical practice. However, the dose-response of metaraminol has not been fully determined and the optimal infusion dose is unknown. Therefore, this study aimed to determine the median effective dose (ED50) and 90% effective dose (ED90) of weight-based fixed-rate metaraminol infusions for preventing spinal-anesthesia-induced hypotension in patients having combined spinal-epidural anesthesia for elective Caesarean delivery. Methods: One hundred and seventeen patients with singleton pregnancies were enrolled and randomly allocated into one of five groups in this study. Patients received prophylactic metaraminol infusion at a fixed rate of 0, 0.25, 1.0, 1.75 or 2.5 μg/kg/min in each group immediately after induction with intrathecal 10 mg of hyperbaric bupivacaine mixed with 5 μg of sufentanil. An effective prophylactic dose was defined as no occurrence of hypotension during the period of spinal introduction and neonatal delivery. Values for ED50 and ED90 of prophylactic infusion of metaraminol were calculated using probit regression. Characteristics of spinal anesthesia and side effects were recorded. Results: The ED50 and ED90 values of weight-based fixed rate of metaraminol infusion were 0.64 (95% CI, 0.04–1.00) μg/kg/min and 2.00 (95% CI, 1.58–2.95) μg/kg/min respectively. The incidence of hypotension decreased with an increased infusion rate of metaraminol in the five groups (test for trend, p < 0.001). The incidence of hypotension was similar between group 0 and 0.25, but significant higher than other groups; the incidence of hypotension was also similar between group 1.0 and 1.75, but higher than group 2.5. The incidence of reactive hypertension was significantly higher in group 2.5 compared to the other groups. Physician interventions were more frequent in group 0, 0.25 and 2.5 than in group 1.0 and 1.75 (adjusted p < 0.001). No difference was found in neonatal outcomes, including Apgar score and pH value of the umbilical artery. Conclusion: In summary, we have compared four different prophylactic weight-based infusion doses of metaraminol for preventing post-spinal hypotension in Cesarean delivery. The ED50 and ED90 values of metaraminol infusion for preventing spinal anesthesia-induced hypotension were 0.64 μg/kg/min and 2.00 μg/kg/min, respectively. This finding may be helpful for guiding clinical practice and further research.

Norepinephrine for the prevention of spinal-induced hypotension during caesarean delivery under combined spinal-epidural anaesthesia: Randomised, double-blind, dose-finding study.

During caesarean delivery under spinal anaesthesia hypotension may be managed by norepinephrine in preference to phenylephrine due a perception of less bradycardia and fewer reductions in cardiac output. As the optimum prophylactic dose of norepinephrine is unclear, we aimed to investigate its dose-response for preventing postspinal hypotension in caesarean delivery. A randomised, double-blinded, dose-finding study. Jiaxing University affiliated Women and Children Hospital, Jiaxing, China. Ninety-nine patients undergoing elective caesarean delivery from 1 February to 5 August: excluding patients with ASA III or above, preeclampsia or hypertension, pre-existing or gestational diabetes, BMI more than 35 kg m, height less than 150 cm or with more than 175 cm, or with contraindications to local anaesthesia. Patients received 0, 0.04, 0.05, 0.06 or 0.07 μg kg min preventive norepinephrine infusions immediately after intrathecal injection of 10 mg bupivacaine with 5 μg sufentanil. The norepinephrine (Median effective dose) or (95% effective dose) ED50 and ED95, which were estimated using Probit analysis to compare haemodynamic changes associated with the different doses. The incidence of hypotension was 70, 47.4, 40, 20 and 15% in the 0, 0.04, 0.05, 0.06 and 0.07 μg kg min groups, respectively. The ED50, ED80 and ED95 values were 0.029 (95% CI 0.008 to 0.042 μg kg min), 0.068 (95% CI 0.055 to 0.099 μg kg min) and 0.105 μg kg min (95% CI 0.082 to 0.172 μg kg min), respectively. Apgar scores or umbilical arterial pH were similar among groups. The ED50, ED80 and ED95 were 0.029, 0.068 and 0.105 μg kg min respectively. A 0.07 μg kg min norepinephrine infusion may be optimum for preventing postspinal hypotension after intrathecal injection of 10 mg bupivacaine combined with 5 μg sufentanil. Chinese Clinical Trial Registry (identifier: ChiCTR-TRC-1800014614).

Impact of Sub-Anesthetic Dose of Ketamine on Post Spinal Hypotension in Cesarean Delivery

Background: Spinal anesthesia is the commonest technique used in Cesarean Section (CS) and most frequently associated with maternal hypotension, for which a lot of techniques have been described to prevent but an effective method is yet to be found. Objectives; The aim was to study the effect of using a sub-anesthetic dose of ketamine to prevent post-spinal hypotension in CS delivery. Methods: This double-blinded randomized controlled study was conducted on 80 participating parturients who were ASA І, П term pregnant. All the parturients received spinal anesthesia. The parturients were then randomly divided into two equal groups (n= 40 in each); ketamine group received a sub-anesthetic dose of ketamine of 0.5 mg/kg IV bolus in 3 ml saline and control group received the same volume of normal saline IV bolus. Heart Rate (HR) and Mean Arterial blood Pressure (MAP) were recorded at baseline (5 minutes prior to the intrathecal injection), at 5, 10, 15 and 20 minutes after the injection and then every 15 minutes till the end of the operation. Incidences of hypotension and severe hypotension were recorded. The total dose of ephedrine was recorded. Ramsay sedation score was recorded at baseline then 5, 10, 15, 30, 45 minutes after injection and then at the end of the operation. Results: Compared to the control group, sedation score was significantly higher among ketamine group at 5, 10 and 15 minutes. MAP and HR were significantly higher among ketamine group at 5, 10, 15, and 20 minutes. Total ephedrine dose was significantly lower among the ketamine group. Mild hypotension and severe hypotension were significantly less frequent among the ketamine group, as all the patients in the control group had an attack of mild hypotension and 55% of this group had an attack of severe hypotension. No significant difference between both the groups regarding diplopia, nystagmus, hallucination, nausea and vomiting. Conclusion: It is concluded that ketamine in a sub-anesthetic dose is an effective agent that can be used in preventing post-spinal hypotension in parturients undergoing CS delivery.

Strategies for Prevention of Spinal-associated Hypotension During Cesarean Delivery: Are We Paying Attention?

(Can J Anaesth 2017;64:991–996) Spinal anesthesia (SA)-induced hypotension is a common complication during cesarean delivery (CD) and can cause a wide range of adverse maternal and neonatal outcomes if untreated. Moore et al’s clinical trial aimed at assessing the median seated time to prevent hypotension in 50% of parturients undergoing elective CD after SA using an up-down sequential methodology. The participants were randomized to receive either 11.25 or 15 mg hyperbaric bupivacaine along with fentanyl 15 µg and morphine 150 µg. It was noted that the median seated time in the 11.25 mg bupivacaine group was a little more than 2 minutes whereas in the 15 mg bupivacaine group the median seated time was approximately 8 minutes, suggesting that extended seated time after SA could prevent hypotension in CD. Further studies elucidating the association of extended seated time and hypotension are essential to design effective prevention strategies for hypotension in CD. The current study was only powered to detect the intervention that prevented hypotension in 50% of patients, which questions its clinical relevance. Disadvantages of the prolonged seated strategy include a delay in surgical start time, reduced operating room efficiency, and shorter duration of anesthesia.

The Median Effective Volume of Crystalloid in Preventing Hypotension in Patients Undergoing Cesarean Delivery with Spinal Anesthesia

Spinal anesthesia-associated maternal hypotension in Cesarean delivery is the most frequent and troublesome complication, posing serious risks to mothers and compromising neonatal well-being. The effective volume of intravenous crystalloid as the preventive strategy in this context has not been estimated. Eighty-five parturients with ASA physical status I/II undergoing elective Cesarean delivery were screened and 67 eligible women were assigned to receive pre-spinal crystalloid loading. Hyperbaric 0.5% bupivacaine 2mL (10mg) plus morphine 50μg was given to all patients. The volume of crystalloid was determined by an up-and-down sequential method. The crystalloid was infused at a rate of 100-150mL.min(-1) prior to the spinal anesthetic injection. The initial volume of crystalloid was 5mL.kg(-1). Volume-effect data were fitted to a sigmoidal maximum efficacy model and the median effective volume (EV(50)) and corresponding 95% confidence interval (95% CI) were estimated using maximum likelihood estimation and logistic regression with Firth's correction. A total of 67 subjects completed the study and were analyzed. Twenty-eight (41.8%) patients developed hypotension with their systolic blood pressure (SBP) decreasing > 20% of baseline. The EV(50) of crystalloid were 12.6mL.kg(-1) (95% CI, 11.6 to 14.8mL.kg(-1)). With Firth's correction, the pooled probability of an effective preventive volume of crystalloid at 13mL.kg(-1) was 50.2% (95% CI, 30% to 83.1%). The estimated EV(50) of the preloaded crystalloid required to prevent spinal anesthesia-induced hypotension in a Cesarean section is, approximately, 13mL.kg(-1). However, prophylactic or therapeutic vasoconstrictors should also be prepared and administered at an appropriate time.

Up-Down Determination of the 90% Effective Dose of Phenylephrine for the Treatment of Spinal Anesthesia-Induced Hypotension in Parturients Undergoing Cesarean Delivery

Hypotension frequently complicates spinal anesthesia for cesarean delivery, and vasopressors are the mainstay for treatment. The most effective dose of phenylephrine for the treatment of spinal anesthesia-induced hypotension has not been estimated. Healthy nonlaboring women undergoing a cesarean delivery were recruited. All women received spinal anesthesia using hyperbaric bupivacaine 12 mg with fentanyl and morphine. Each subject received an i.v. crystalloid fluid bolus before and at the time of initiation of spinal anesthesia (preload and coload). An up-down sequential allocation method using the biased-coin design was used to estimate the 90% effective dose (ED(90)) of phenylephrine. The assigned phenylephrine dose was based on the response of the preceding subject. If the systolic blood pressure (SBP) decreased > 20% of baseline (i.e., SBP 20%) or to an SBP < 90 mm Hg, the assigned dose of phenylephrine was administered. If the SBP returned to within 20% of baseline or > or = 90 mm Hg within 1 min, this was considered a success, otherwise it was a failure. The initial dose of phenylephrine was 100 microg. The ED(90) with 95% confidence intervals (CIs) was calculated using the maximum likelihood estimation and Firth logistic regression. Sixty-nine subjects were screened to participate, of whom 66 subjects consented. Forty-five of the enrolled subjects experienced spinal anesthesia-induced hypotension and received a blinded dose of phenylephrine. Those subjects who developed hypotension received doses of phenylephrine between 80 and 180 microg. No subjects experienced hypertension. Determined with the maximum likelihood estimation method, the ED(90) of phenylephrine was 147 microg (95% CI, 98-222 microg). With Firth regression, the probability of a successful response at 150 microg is 90.5% (95% CI, 66.0%-99.0%). In this study, we estimated that the ED(90) of phenylephrine required to treat spinal anesthesia-induced hypotension in cesarean delivery is approximately 150 microg.