The effect of intrathecal dexmedetomidine on the dose requirement of hyperbaric bupivacaine in spinal anaesthesia for caesarean section: a prospective, double-blinded, randomized study

Abstract

BackgroundStudies have shown that dexmedetomidine (Dex) can prolong the duration of analgesia when added to local anaesthetic as an adjuvant in a central or peripheral nerve block. We hypothesized that intrathecal Dex can reduce the ED95 of spinal hyperbaric bupivacaine. Therefore, we conducted this prospective, double-blinded, randomized study to verify our hypothesis.MethodsNinety patients were allocated into the Dexmedetomidine group (received bupivacaine + 5 mcg dexmedetomidine) and the Control group (received bupivacaine + the same volume of saline) using a double-blinded and randomized method. The first patient in each group received 5 mg of IT hyperbaric bupivacaine, and the next dose for the following patient was determined by the probability of successful anaesthesia of the previous neighbouring dose. An improved up-down sequence allocated method combined with probit analysis was used to determine the ED95 of intrathecal hyperbaric bupivacaine for the two groups.ResultsThe ED95 and 95% confidence intervals (95% CI) of IT hyperbaric bupivacaine of the Dex group and Control group were 8.4 mg (95% CI, 6.5~ 13.8 mg) and 12.1 mg (95% CI, 8.3~ 312.8 mg), respectively. The duration of sensory block was longer in the Dex group than in the Control group (110.3 ± 35.3 vs 67.5 ± 26.2). The duration of analgesia was also longer in the Dex group than in the Control group (224.9 ± 45.4 vs 155.1 ± 31.6). The consumption of postoperative rescued sufentanil was significantly higher in the Control group than in the Dex group.ConclusionIntrathecal 5 mcg dexmedetomidine potentiated hyperbaric bupivacaine antinociception by 31% in spinal anaesthesia for patients undergoing caesarean section.Trial registrationWe registered this study in a Chinese Clinical Trial Registry (ChiCTR) centre on Nov 1st 2016 and received the registration number: ChiCTR-IPR-16009699.

Effect of Different Doses of Intrathecal Dexmedetomidine as an Adjuvant Combined With Hyperbaric Ropivacaine in Patients Undergoing Cesarean Section

“…But intrathecal opioids will increase nausea and vomiting (Weigl et al, 2017) and itching (Sun et al, 2001;Chen et al, 2010;Sun et al, 2017) that is an uncomfortable experience and prolong the recovery for the parturients after the surgery. Intrathecal dexmedetomidine, an a 2 -adrenergic receptor agonist used as an adjuvant to bupivacaine, has been found to provide better intraoperative nerve blockade than bupivacaine alone as well as prolong postoperative analgesia and alleviate shivering in patients undergoing cesarean section (Bi et al, 2017;He et al, 2017;Xia et al, 2018;Liu et al, 2019). And this minimal dose of intrathecal dexmedetomidine after absorbed into blood and metabolized by the liver may not cause potential fetal toxicity based on the previous studies (Bi et al, 2017;He et al, 2017;Xia et al, 2018;Liu et al, 2019).…”

“…Intrathecal dexmedetomidine, an a 2 -adrenergic receptor agonist used as an adjuvant to bupivacaine, has been found to provide better intraoperative nerve blockade than bupivacaine alone as well as prolong postoperative analgesia and alleviate shivering in patients undergoing cesarean section (Bi et al, 2017;He et al, 2017;Xia et al, 2018;Liu et al, 2019). And this minimal dose of intrathecal dexmedetomidine after absorbed into blood and metabolized by the liver may not cause potential fetal toxicity based on the previous studies (Bi et al, 2017;He et al, 2017;Xia et al, 2018;Liu et al, 2019). Zhou et al found that dexmedetomidine can reduce the traumatic stress response and immune suppression caused by surgery and has a protective effect on the spinal cord in spinal surgery (Zhou et al, 2017).…”

Assessing the Benefits of Adding Dexmedetomidine to Intrathecal Hyperbaric Bupivacaine for Caesarean Section

“…Dose of 2.5 -10 gm is considered optimal for intrathecal use by many authors. [3][4] So we took 5gm Dexmedetomidine as optimum dose for intrathecal addition to Bupivacaine in this study. 13 In present study Group D received intrathecal hyperbaric Bupivacaine 0.5% 9 mg (1.8 ml) and Dexmedetomidine 5µgm while group C received intrathecal hyperbaric Bupivacaine 0.5% 9 mg (1.8 ml) and 0.9% saline.…”

“…They potentiate the effect of local anaesthetics and allows a decrease in the required dose. [3][4] Both of these drugs are well studied as intrathecal adjuvants in orthopaedic and general surgeries. 5 Dexmedetomidine, is 8 times more selective α 2 adrenergic receptor agonist as compared to Clonidine, thus it can be safely used as intrathecal adjuvant in caesarean surgeries due to its limited effects on respiratory system and level of patient's consciousness during surgery.…”

Fetal and Maternal Responses to Dexmedetomidine Intrathecal Application During Cesarean Section: A Meta-Analysis

“…The meta-analysis ultimately included 10 RCTs (Figure 1) with a total of 706 patients, of which 9 studies [10,21,22,[24][25][26][27][28][29] used bupivacaine and 1 study [23] used lidocaine for spinal anesthesia. In these studies, 6 compared DEX with saline, and the remaining 4 studies compared DEX with tramadol and saline, clonidine with DEX and saline and fentanyl, DEX with morphine and saline, and DEX with saline and fentanyl, respectively.…”