Sufentanil and Bupivacaine Combination versus Bupivacaine Alone for Spinal Anesthesia during Cesarean Delivery: A Meta-Analysis of Randomized Trials

Mechanisms and treatment of opioid-induced pruritus: Peripheral and central pathways

BACKGROUND AND OBJECTIVE

Pruritus (also known as itch) is defined as an unpleasant and irritating sensation of the skin that provokes an urge to scratch or rub. It is well known that opioid administration can cause pruritus, which is paradoxical as itch and pain share overlapping sensory pathways. Because opioids inhibit pain but can cause itching. Significant progress has been made to improve our understanding of the fundamental neurobiology of itch; however, much remains unknown about the mechanisms of opioid-induced pruritus. The prevention and treatment of opioid-induced pruritus remains a challenge in the field of pain management. The objective of this narrative review is to present and discuss the current body of literature and summarize the current understanding of the mechanisms underlying opioid-induced pruritus, and its relationship to analgesia, and possible treatment options.

RESULTS

The incidence of opioid-induced pruritus differs with different opioids and routes of administration, and the various mechanisms can be broadly divided into peripheral and central. Especially central mechanisms are intricate, even at the level of the spinal dorsal horn. There is evidence that opioid receptor antagonists and mixed agonist and antagonists, especially μ-opioid antagonists and κ-opioid agonists, are effective in relieving opioid-induced pruritus. Various treatments have been used for opioid-induced pruritus; however, most of them are controversial and have conflicting results.

CONCLUSION

The use of a multimodal analgesic treatment regimen combined with a mixed antagonist and κ agonists, especially μ-opioid antagonists, and κ-opioid agonists, seems to be the current best treatment modality for the management of opioid-induced pruritus and pain.

SIGNIFICANCE

Opioids remain the gold standard for the treatment of moderate to severe acute pain as well as cancer pain. It is well known that opioid-induced pruritus often does not respond to regular antipruritic treatment, thereby posing a challenge to clinicians in the field of pain management. We believe that our review makes a significant contribution to the literature, as studies on the mechanisms of opioid-induced pruritus and effective management strategies are crucial for the management of these patients.

Post-cesarean Delivery Analgesia Using Spinal Anesthesia: Ropivacaine-Fentanyl vs. Ropivacaine-Sufentanil

Background

To improve the quality of intraoperative and postoperative analgesia during spinal anesthesia, intrathecal opioids are used as adjuvant drugs in combination with local anesthetics.

Objectives

This study aimed to compare the intrathecal injection of ropivacaine-fentanyl with ropivacaine-sufentanil in terms of the duration of analgesia after cesarean section (CS).

Methods

This randomized, double-blind clinical trial study was conducted on women referred to Imam Khomeini Hospital of Ahvaz City for elective CS in 2021. A total of 51 patients were randomly divided into 2 groups. The first group (n = 25) received ropivacaine (17.5 mg) + fentanyl (25 μg), while the second group (n = 26) received ropivacaine (17.5 mg) + sufentanil (2.5 μg) for spinal anesthesia. Eventually, several parameters were investigated, including the duration of sensory and motor block, duration of analgesia (based on the Visual Analog Scale (VAS)), hemodynamic parameters, and possible complications.

Results

The duration of surgery (P = 0.059) and the duration of motor block (P = 0.962) were not significantly different between the 2 groups. The mean duration of analgesia (from the time of entering recovery to reaching VAS = 3) was 203.12 ± 72.93 and 207.46 ± 69.59 minutes in the fentanyl and sufentanil groups, respectively (P = 0.658). Systolic and diastolic blood pressure (SBP/DBP) drops in minute 5 were observed more frequently in the sufentanil group than in the fentanyl group (P = 0.027 and P = 0.002, respectively). At the other time points, however, no significant difference was observed between the 2 groups in terms of hemodynamic variables (P > 0.05). Finally, the frequency of pruritus was higher in the sufentanil group than in the fentanyl group (26.9% vs. 4.0%; P = 0.024).

Conclusions

Adding fentanyl or sufentanil to intrathecal ropivacaine provides a similar duration of analgesia. However, fentanyl was associated with better hemodynamic stability and a lower incidence of pruritus.

A Comparative Study on the Effect of Intrathecal Bupivacaine vs. Ropivacaine on Maternal and Neonatal Outcomes After Cesarean Section: A Systematic Review and Meta-analysis

Context

The type of anesthesia in cesarean section can affect the mother and baby. This study aimed to determine the comparative effect of intrathecal hyperbaric bupivacaine vs. hyperbaric ropivacaine on maternal and neonatal outcomes after cesarean section.

Evidence Acquisition

PubMed, Web of Science, Embase, Google Scholar, IranDoc, MagIran, and Scopus databases were searched from 1 September 2022 to 1 November 2022. Eighteen clinical trials with 1542 patients were included in the analysis.

Results

There was no statistically significant difference in hypotension, bradycardia, and Apgar score between the 2 groups (P > 0.05). The risk of nausea (relative risk (RR), 1.526; 95% CI, 1.175 - 1.981; P = 0.001) and vomiting (RR, 1.542; 95% CI, 1.048 - 2.268; P = 0.02) caused by bupivacaine was 0.53% and 0.54% higher than that of ropivacaine. The incidence of shivering (RR, 2.24; 95% CI, 1.480 - 3.39; P = 0.00) was 2.24 times higher in the bupivacaine group than in the ropivacaine group. The average onset time of sensory block (standardized mean difference (SMD), -0.550; 95% CI, -1.054 to -0.045; P = 0.032) and motor block (SMD, -0.812; 95% CI, -1.254 to -0.371; P = 0.000) was significantly lower in the bupivacaine group than in the ropivacaine group.

Conclusions

Despite the fact that ropivacaine and bupivacaine are effective in cesarean section, ropivacaine is more favorable because of less hemodynamic changes, less duration of sensory and motor block, and fewer side effects, which are effective in patient recovery.

Comparison of dexmedetomidine and remifentanil on reducing coughing during emergence from anesthesia with tracheal intubation: A meta-analysis

Background: Dexmedetomidine and remifentanil are well known to suppress airway reflex during emergence from anesthesia, but which one is more effective is unclear. We conducted a meta-analysis to compare the effect of dexmedetomidine and remifentanil on reducing the occurrence of coughing.

Methods: We systematically searched PubMed, Embase, and Cochrane Library for randomized controlled trials (published between 1 January 1950, and 30 December 2021; no language restrictions) comparing dexmedetomidine infusion with remifentanil infusion. The primary endpoint was the incidence of moderate to severe coughing during the recovery period. The secondary endpoints were the time of recovery and extubation, and residual sedation. We assessed pooled data by using a random-effects model.

Results: Eight studies with 502 participants were included. The meta-analysis showed no statistically difference between dexmedetomidine and remifentanil in the occurrence of moderate to severe coughing during emergence from anesthesia (OR 1.45,95%CI 0.62–3.38), the extubation time (MD 0.93 min, 95%CI -0.28–2.14), and the residual sedation (OR 2.52, 95%CI 0.92–6.91). Compared with dexmedetomidine, the average recovery time of remifentanil was shorter (MD 3.88 min, 95%CI 1.01–6.75).

Conclusion: Dexmedetomidine and remifentanil infusion had no difference in the occurrence of moderate to severe coughing during emergence from anesthesia.

Clinical Trial Registration:https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42021239710

Maternal and neonatal outcomes with the addition of intrathecal midazolam as an adjuvant to spinal anesthesia in cesarean delivery: A systematic review and meta-analysis of randomized controlled trials

STUDY OBJECTIVE

To determine the efficacy and safety, in terms of maternal and neonatal outcomes, of adding intrathecal midazolam to spinal anesthesia for cesarean delivery in healthy pregnant women.

DESIGN

A meta-analysis of randomized controlled trials was conducted. PubMed, Cochrane Library, Embase, and Web of Science were searched manually, and citation screening was completed on May 20, 2021.

SETTING

Most of the included data were collected in the operating room and postoperative recovery area.

PATIENTS

A total of 1382 healthy parturients undergoing cesarean delivery with single-shot spinal anesthesia were recruited in 19 eligible randomized controlled trials.

INTERVENTIONS

Single intrathecal midazolam adjuvant was compared to a control, with the local anesthetic dose in spinal anesthesia identical between the intervention and control groups.

MEASUREMENTS

The primary outcomes were time to first analgesic use, maternal adverse effects, and neonatal Apgar scores at 1 and 5 min. The secondary outcomes were the onset and duration of the sensory and motor blocks.

MAIN RESULTS

Adjuvant intrathecal midazolam prolonged the time to the first analgesic (mean difference [MD]: 59.96 min, 95% confidence interval [CI]: [23.12, 96.79]) and decreased perioperative maternal nausea and/or vomiting (odds ratio [OR], 0.28; 95% CI: [0.17, 0.45]). However, more sedation events were observed with midazolam (OR, 3.93; 95% CI: [1.12, 13.78]). There was no significant difference in the neonatal Apgar scores at 1 or 5 min (MD: -0.29, 95% CI: [-0.61, 0.03]; MD: -0.00, 95% CI: [-0.11, 0.1], respectively). Intrathecal midazolam also shortened sensory and motor block onset by less than 1 min and prolonged sensory block duration but had no significant effect on motor block duration.

CONCLUSIONS

Current evidence indicates that intrathecal midazolam, as an adjuvant to spinal anesthesia, provides modest analgesic and significant antiemetic effects at the cost of more sedation events in cesarean delivery patients. The neonatal Apgar score was not affected by intrathecal midazolam administration. However, more objective, sensitive, and long-term measurements of neonatal safety and maternal neurological effects should be performed in the future.

Effectiveness of Patient-Controlled Intravenous Analgesia (PCIA) with Sufentanil Background Infusion for Post-Cesarean Analgesia: A Randomized Controlled Trial

Purpose

To investigate the effectiveness of sufentanil patient-controlled intravenous analgesia pump (PCIA) and background infusion in patients of post-cesarean analgesia.

Patients and Methods

This trial compared two groups of women undergoing cesarean section and receiving PCIA: no background infusion group (n=30), 6-min lockout time, and background infusion group (n=30), 2 mL/h infusion, 10-min lockout time. Both groups with 2 μg/kg sufentanil was diluted to 100 mL with normal saline. VAS scores at rest at 36 h was the primary endpoint. The secondary endpoints were the VAS scores at rest at 6, 12, and 24 h, the total amount of sufentanil consumed, the Ramsay sedation score (RSS) assessed at the same time points, postpartum bleeding within 24 h, the injection/attempt (I/A) ratio, BP and HR, PONV, side effects of sufentanil.

Results

Compared with the no background infusion group, the background infusion group showed lower VAS pain scores at 6, 12, and 24 h (P<0.01), but no differences at 36 h (95% CI = -0.5-0.8. P>0.05). Attempts, injections, and total sufentanil consumption were significantly different between the two groups (P<0.001), but without difference in I/A. Bleeding was less in the background infusion group at 1 h (P=0.03). The minimal respiration rates were not significantly different between groups.

Conclusion

Background infusion increased the total consumption of sufentanil within 36 h after cesarean section. Although it did not reduce uterine contraction pain and wound pain at 36 h, it significantly reduced the pain at 6, 12, and 24 h after cesarean section. It improved patient satisfaction and reduced the amount of bleeding after 1 h. Importantly, it did not increase the incidence of hypertension, PONV and respiratory depression.

Sufentanil for Spinal Analgesia during Cesarean Section Delivery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To investigate the effect of sufentanil for spinal analgesia during cesarean section.

METHOD

Eligible papers were systematically retrieved from PubMed, Embase, Ovid, and ScienceDirect. Two researchers independently extracted primary and secondary endpoints to compute relative risk and mean difference by using the random-effects model or the fixed-effects model, as appropriate. Publication bias was quantified and assessed using funnel plot and Egger's test.

RESULT

A total of 8 publications with 503 pregnant women were included in this study for meta-analysis. Subarachnoid administration of sufentanil did not significantly reduce the onset time of sensory block and motor block. Nonetheless, subarachnoid administration of sufentanil significantly increased the incidence of postoperative skin pruritus (RR = 5.25, 95%CI: 1.90, 14.49, P < 0.001).

CONCLUSION

Subarachnoid administration of sufentanil has no significant difference in the combined effect value of shortening the onset time of sensory block and motor block, prolonging the onset time of local anesthesia and the incidence of some adverse reactions (such as postoperative nausea, vomiting, hypotension, and tremors). However, the incidence of skin pruritus was significantly increased, and the difference was statistically significant. Because of this, the drug still needs to be used with caution in combination with the actual situation in clinical use.

The Options for Neuraxial Drug Administration

Neuraxial drug administration, i.e., the injection of drugs into the epidural or intrathecal space to produce anesthesia or analgesia, is a technique developed more than 120 years ago. Today, it still is widely used in daily practice in anesthesiology and in acute and chronic pain therapy. A multitude of different drugs have been introduced for neuraxial injection, only a part of which have obtained official approval for that indication. A broad understanding of the pharmacology of those agents is essential to the clinician to utilize them in a safe and efficient manner. In the present narrative review, we summarize current knowledge on neuraxial anatomy relevant to clinical practice, including pediatric anatomy. Then, we delineate the general pharmacology of neuraxial drug administration, with particular attention to specific aspects of epidural and intrathecal pharmacokinetics and pharmacodynamics. Furthermore, we describe the most common clinical indications for neuraxial drug administration, including the perioperative setting, obstetrics, and chronic pain. Then, we discuss possible neurotoxic effects of neuraxial drugs, and moreover, we detail the specific properties of the most commonly used neuraxial drugs that are relevant to clinicians who employ epidural or intrathecal drug administration, in order to ensure adequate treatment and patient safety in these techniques. Finally, we give a brief overview on new developments in neuraxial drug therapy.

Paravertebral Block versus Thoracic Epidural Analgesia for Postthoracotomy Pain Relief: A Meta-Analysis of Randomized Trials

OBJECTIVE

 Paravertebral block (PVB) and thoracic epidural analgesia (TEA) are commonly used for postthoracotomy pain management. The purpose of this research is to evaluate the effects of TEA versus PVB for postthoracotomy pain relief.

METHODS

 A systematic literature search was conducted in PubMed, EMBASE, Web of Science, and the Cochrane Library (last performed on August 2020) to identify randomized controlled trials comparing PVB and TEA for thoracotomy. The rest and dynamic visual analog scale (VAS) scores, rescue analgesic consumption, the incidences of side effects were pooled.

RESULTS

 Sixteen trials involving 1,000 patients were included in this meta-analysis. The pooled results showed that the rest and dynamic VAS at 12, 24, and rest VAS at 48 hours were similar between PVB and TEA groups. The rescue analgesic consumption (weighted mean differences: 3.81; 95% confidence interval [CI]: 0.982-6.638, p < 0.01) and the incidence of rescue analgesia (relative risk [RR]: 1.963; 95% CI: 1.336-2.884, p < 0.01) were less in TEA group. However, the incidence of hypotension (RR: 0.228; 95% CI: 0.137-0.380, p < 0.001), urinary retention (RR: 0.392; 95% CI: 0.198-0.776, p < 0.01), and vomiting (RR: 0.665; 95% CI: 0.451-0.981, p < 0.05) was less in PVB group.

CONCLUSION

 For thoracotomy, PVB may provide no superior analgesia compared with TEA but PVB can reduce side effects. Thus, individualized treatment is recommended. Further study is still necessary to determine which concentration of local anesthetics can be used for PVB and can provide equal analgesic efficiency to TEA.

Strategies of analgesic treatment after cesarean delivery. Current state and new alternatives

The number of caesarean sections performed worldwide is increasing, and with it, the need for the optimal analgesia strategies. Deficient postoperative analgesia increases the need for opioids, delays recovery, and is associated with chronic pain and postpartum depression. It is essential to find good postoperative pain control strategies that facilitate early mobility, early recovery, and early hospital discharge with minimal side effects on the mother and infant. Multimodal analgesia based on neuroaxial anaesthesia with morphine in combination with non-opioids such as non-steroidal anti-inflammatory drugs and paracetamol, gives the best post-caesarean analgesia outcome, and allows anaesthesiologists to reserve opioids, corticoids, gabapentin, magnesium or ketamine for situations where neuroaxial anaesthesia cannot be performed, for high-risk patients, or when pain is difficult to control. Peripheral nerve block techniques can also be added, such as transverse abdominis plane block, erector spinae block, or continuous wound infiltration.

Dexmedetomidine and sufentanil combination versus sufentanil alone for postoperative intravenous patient-controlled analgesia: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Previous studies have demonstrated that dexmedetomidine improves the quality of postoperative analgesia. In the present study, we performed a meta-analysis of randomized controlled trials to quantify the effect of dexmedetomidine as an adjuvant to sufentanil for postoperative patient-controlled analgesia (PCA).

METHODS

PubMed, Embase, the Cochrane Library, and Web of Science were systematically searched for randomized controlled trials in which dexmedetomidine was used as an adjuvant for PCA with sufentanil. In the retrieved studies, we quantitatively analyzed pain intensity, sufentanil consumption, and drug-related side effects.

RESULTS

Nine studies with 907 patients were included in this meta-analysis. Compared with sufentanil alone, dexmedetomidine-sufentanil for postoperative intravenous PCA reduced pain intensity at 24 h (mean difference (MD) = - 0.70points; 95% confidence interval (CI): - 1.01, - 0.39; P < 0.00001) and 48 h postoperatively (MD = -0.61points; 95% CI: - 1.00, - 0.22; P = 0.002). Moreover, dexmedetomidine-sufentanil reduced sufentanil consumption during the first 24 h (MD = -13.77 μg; 95% CI: - 18.56, - 8.97; P < 0.00001) and 48 h postoperatively (MD = -20.81 μg; 95% CI: - 28.20, - 13.42; P < 0.00001). Finally, dexmedetomidine-sufentanil improved patient satisfaction without increasing the incidence of side effects.

CONCLUSIONS

Dexmedetomidine as an adjuvant to sufentanil for postoperative PCA can reduce postoperative pain score and sufentanil consumption.

Combining Spinal-Epidural Anesthesia versus Single-Shot Spinal Anesthesia for Cesarean Delivery: A Meta-Analysis of 5 Randomized Controlled Trials

Background

This study compared combined spinal-epidural anesthesia (CSEA) and single-shot spinal anesthesia (SSSA) by performing a meta-analysis.

Material/Methods

An electronic search of relevant studies was done through 2017. Primary endpoints included duration of surgery, and time for (1) sensory recovery to thoracic vertebra (T10), (2) maximal sensory, (3) motor blockade, and (4) motor recovery. Secondary endpoints were the adverse effects. RevMan 5.3 analytical software was used with odds ratios (OR) and 95% confidence intervals (CIs) as the analytic parameters. Standard deviation and mean were used to evaluate data by weighted mean differences (WMDs) with 95% CI.

Results

A total of 370 patients were analyzed. A similar duration of surgery was observed with CSEA and SSSA (WMD: 0.24, 95%CI: −3.41–3.89; P=0.90). Time to maximal sensory blockade (WMD: 0.96, 95%CI: −2.91–4.83), time to maximal motor blockade (WMD: 0.25, 95%CI: −2.46–2.96), time for complete motor recovery (WMD: −6.28, 95%CI: −29.42–16.86), and time for sensory recovery to T10 vertebra (WMD: 0.42, 95%CI: −11.07–11.91) were not significantly different. Adverse effects such as hypotension (OR: 1.49, 95%CI: 0.27–8.31), pruritus (OR: 0.23, 95%CI: 0.03–2.18), nausea/vomiting (OR: 0.84, 95%CI: 0.12–5.99). and shivering (OR: 0.53, 95%CI: 0.11–2.56) were also similar with CSEA and SSSA.

Conclusions

CSEA was not associated with significantly different maximal duration of sensory/motor blockade, complete motor recovery, sensory regression to T10, or adverse drug events compared to SSSA. Hence, both should be considered effective in cesarean delivery.

The dose response of sufentanil as an adjuvant to ropivacaine in cesarean section for relief from somato-visceral pain under epidural anesthesia in parturients with scarred uterus

Visceral pain is common during epidural anesthesia with mini dose local anesthetics in parturients during cesarean section. To reduce or avoid this complication caused by traction on the abdominal viscera, this study aimed to determine the 50% effective dose (ED50) and 95% effective dose (ED95) of epidural sufentanil as an adjuvant combination with local anesthetics for relief visceral pain in parturients with scarred uterus undergoing elective cesarean section.One hundred parturients with scarred uterus undergoing elective cesarean section under epidural anesthesia were enrolled in this randomized, double-blinded, dose-ranging study. Parturients received 5, 10, 15, 20, and 25 μg epidural sufentanil as an adjuvant with 10 mL of 0.65% ropivacaine. Successful epidural anesthesia was defined as a sixth thoracic vertebra (T6) sensory level achieved within 20 minutes after epidural drugs administration and/or no visceral pain by traction on the abdominal viscera during the cesarean section. The ED50 and ED95 were calculated with a logistic regression model.ED50 and ED95 of epidural sufentanil for successful of the pain-free from visceral pain were 10.7 μg [95% confidence interval (CI): 2.4-14.4 μg) and 28.1 μg (95% CI: 19.4-44.0 μg), respectively. The onset time to sensory block, maximum Bromage scale and duration of motor block were significant different with dose of sufentanil >20 μg (P < .05, compared with the other dose groups). With the dose of epidural sufentanil >20 μg could result in an increase of incidence of maternals' adverse effects. Compared with a different dose of sufentanil, epidural administed sufentanil between 15 μg and 20 μg can maximize parturients' satisfaction.Our study showed that sufentanil could be used in combination with ropivacaine for relief from somato-visceral pain in patients with scarred uterus during elective cesarean section during epidural anesthesia, and that maximized parturients' satisfaction could be achieved when the use of sufentanil with the dose between 15 μg and 20 μg for epidural anesthesia.

Sufentanil Alleviates Intrathecal Lidocaine Induced Prolonged Sensory and Motor Impairments but not the Spinal Histological Injury in Rats

Spinal anesthesia has evolved into a safe and widely accepted method of anesthesia. Synergy between opioids and local anesthetics further increases the quality of analgesia and decreases the dose requirement of both local anesthetics and opioids. However, over the last decades compelling evidence suggested that lidocaine could be more neurotoxic than other commonly used local anesthetics. Whether opioids can modify the local anesthetics-induced neurotoxicity is largely unexplored. Here, we investigated the effect of sufentanil on the neurotoxicity induced by intrathecal lidocaine in a rat model. Our data showed that 5 µg/ml sufentanil didn't deteriorate nor reduce the histopathological injuries induced by intrathecal application of 10% lidocaine in a rat model. However, it did alleviate sensory and motor function impairments induced by 10% lidocaine. Repeated intrathecal injection of 5 µg/ml sufentanil also decreased the paw withdraw threshold compared to the baseline. An increase in expression of activating transcription factor 3, a stress response gene, as a marker for injured neurons, was also detected in lidocaine-induced neurotoxicity, while 5 µg/ml sufentanil inhibited lidocaine-induced the upregulation of activating transcription factor 3. These results suggest that sufentanil alleviates lidocaine induced sensory and motor impairments, and did not worsen histopathological injury induced by intrathecal lidocaine.

Maternal and anaesthesia-related risk factors and incidence of spinal anaesthesia-induced hypotension in elective caesarean section: A multinomial logistic regression

BACKGROUND AND AIMS

Although spinal anaesthesia (SA) is nowadays the preferred anaesthesia technique for caesarean section (CS), it is associated with considerable haemodynamic effects, such as maternal hypotension. This study aimed to evaluate a wide range of variables (related to parturient and anaesthesia techniques) associated with the incidence of different degrees of SA-induced hypotension during elective CS.

METHODS

This prospective study was conducted on 511 mother-infant pairs, in which the mother underwent elective CS under SA. The data were collected through preset proforma containing three parts related to the parturient, anaesthetic techniques and a table for recording maternal blood pressure. It was hypothesized that some maternal (such as age) and anaesthesia-related risk factors (such as block height) were associated with occurance of SA-induced hypotension during elective CS.

RESULTS

The incidence of mild, moderate and severe hypotension was 20%, 35% and 40%, respectively. Eventually, ten risk factors were found to be associated with hypotension, including age >35 years, body mass index ≥25 kg/m2, 11-20 kg weight gain, gravidity ≥4, history of hypotension, baseline systolic blood pressure (SBP) <120 mmHg and baseline heart rate >100 beats/min in maternal modelling, fluid preloading ≥1000 ml, adding sufentanil to bupivacaine and sensory block height >T4in anaesthesia-related modelling (P < 0.05).

CONCLUSION

Age, body mass index, weight gain, gravidity, history of hypotension, baseline SBP and heart rate, fluid preloading, adding sufentanil to bupivacaine and sensory block hieght were the main risk factors identified in the study for SA-induced hypotension during CS.