Intrathecal clonidine prolongs labour analgesia but worsens fetal outcome: a pilot study

Sufentanil vs. Dexmedetomidine as Neuraxial Adjuvants in Cesarean Section: A Mono-Centric Retrospective Comparative Study

Spinal anesthesia is the best choice for caesarean delivery. This technique is characterized by a complete and predictable nerve block with a fast onset and few complications. Several intrathecal adjuvants are used in order to improve the quality and duration of anesthesia and reduce its side effects. Sixty-two patients who underwent caesarean delivery under spinal anesthesia were included in this medical records review. In this retrospective study, after adopting exclusion criteria, we assessed 24 patients who received Hyperbaric Bupivacaine 0.5% 10 mg and dexmedetomidine 10 μg (G1), and 28 patients who received an institutional standard treatment with Hyperbaric Bupivacaine 0.5% 10 mg and sufentanil 5 μg (G2). We evaluated the difference in terms of motor and sensory block, postoperative pain, and adverse effects during the first 24 h following delivery and neonatal outcome. Our study found that the sufentanil group had a significantly lower requirement for analgesia than the dexmedetomidine group. Postoperative pain, assessed with the VAS scale, was stronger in G1 than in G2 (4 ± 2 vs. 2 ± 1, p-value < 0.01). Differences between the two groups regarding the intraoperative degree of motor and sensory block, motor recovery time, and neonatal Apgar scores were not noticed. Pruritus and shivering were observed only in G2. Itching and shivering did not occur in the dexmedetomidine group. Postoperative analgesia was superior in the sufentanil group, but the incidence of side effects was higher. Adjuvant dexmedetomidine prevented postoperative shivering.

Neuraxial labor analgesia: is there a place for neuraxial adjuvants beyond opioids

Neuraxial labor analgesia is considered the gold standard technique for analgesia. Ideally, a good neuraxial technique uses dilute local anesthetic solutions to produce effective pain relief with no or minimal motor impairment. Adjuvant drugs that are co-administered with the local anesthetic either epidurally or intrathecally are useful in achieving this goal. The current review focuses on the effectivity and side-effect profile of various commonly used or tested adjuvants.

Pharmacodynamics of intrathecal and epidural fadolmidine, an α2-adrenoceptor agonist, after bolus and infusion in dogs-comparison with clonidine

An α₂-adrenoceptor agonist, clonidine, is extensively used in both anesthesia and intensive care medicine. However, clonidine may produce pronounced hemodynamic side effects such as hypotension and bradycardia which may limit its usefulness in certain conditions. Fadolmidine is a potent α₂-adrenoceptor agonist with different physicochemical properties than clonidine. Here, the effects of fadolmidine and clonidine on analgesia (an increase in thermal skin twitch response latency), sedation, blood pressure, heart rate, respiratory rate, and body temperature were evaluated either up to 8 h after either intrathecal or epidural bolus injections or during a 24-h continuous intrathecal infusion at equipotent analgesic doses in non-anesthetized Beagle dogs. Fadolmidine and clonidine produced a dose-dependent and equipotent maximal antinociception after intrathecal bolus injection (ED₅₀: 67 μg and 78 μg, respectively), but the duration of action of fadolmidine was more long-lasting. During the intrathecal infusion, fadolmidine achieved a good analgesic effect without evoking cardiovascular side effects, e.g., hypotension; these were evident during clonidine infusion. Epidurally, the antinociceptive potency of fadolmidine was weaker (ED₅₀: 128 μg) than when intrathecally administered and weaker than that of epidural clonidine (ED₅₀: 51 μg). At analgesic doses, fadolmidine injection induced moderate initial hypertension concomitantly with a decrease in heart rate whereas clonidine evoked hypotension and bradycardia. These results suggest that especially when non-opioid long-term pain relief is needed, an intrathecal infusion of fadolmidine can provide long-term antinociception with less of the known use-limiting adverse effects associated with clonidine.

Outcomes of intrathecal analgesia in multiparous women undergoing normal vaginal delivery: A randomised controlled trial

Background and Aims

Although intrathecal analgesia is an effective option during labour, there is a need to establish sustainable and assured analgesia during the entire labour process. We aimed to assess the effect of adding dexmedetomidine, fentanyl or morphine to low-dose bupivacaine-dexamethasone for intrathecal labour analgesia in multiparous women.

Methods

This was a triple-blind, randomised controlled trial that included 140 multiparous women. Eligible women were randomly allocated to have intrathecal bupivacaine-dexamethasone with dexmedetomidine (group D), fentanyl (group F), morphine (group M) or saline (placebo) (group C). The duration of analgesia, intrathecal block characteristics and maternal and foetal outcomes were assessed and analysed.

Results

The longest analgesia duration and S1 regression time was recorded in group D followed by groups M, F and C, respectively, with statistical significance between all of them (P < 0.001). The shortest analgesia onset time and the highest sensory levels were recorded in group D followed by group F then group M with statistical significance between all of them (P < 0.001 and 0.003, respectively). Visual analogue scale values were comparable among groups M, F and D (P > 0.05) at most of the measurement time points and at the peak of the last uterine contraction before delivery while being significantly lower than those in group C (P < 0.001). However, there were similar motor block characteristics and normal neonatal outcomes in all groups.

Conclusion

In comparison to morphine and fentanyl, dexmedetomidine addition to intrathecal bupivacaine-dexamethasone significantly prolonged the duration and accelerated the onset of labour analgesia, with a good maternal and neonatal outcome.

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

Background

Studies 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.

Methods

Ninety 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.

Results

The 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.

Conclusion

Intrathecal 5 mcg dexmedetomidine potentiated hyperbaric bupivacaine antinociception by 31% in spinal anaesthesia for patients undergoing caesarean section.

Trial registration

We registered this study in a Chinese Clinical Trial Registry (ChiCTR) centre on Nov 1st 2016 and received the registration number: ChiCTR-IPR-16009699.

The impact of neuraxial clonidine on postoperative analgesia and perioperative adverse effects in women having elective Caesarean section-a systematic review and meta-analysis

Neuraxial clonidine improves postoperative analgesia in the general surgical population. The efficacy and safety of neuraxial clonidine as a postoperative analgesic adjunct in the Caesarean section population still remains unclear. This systematic review and meta-analysis aims to evaluate the effect of perioperative neuraxial clonidine on postoperative analgesia in women having Caesarean section under neuraxial anaesthesia. We included randomized controlled trials comparing the analgesic efficacy of the perioperative administration of neuraxial clonidine alone or in combination with a local anaesthetic and/or opioids in women having elective Caesarean section under neuraxial anaesthesia when compared with placebo. PubMed, the Cochrane Central Register of Controlled Trials, and EMBASE were searched until February 2017. Eighteen studies were included in the meta-analysis. Neuraxial clonidine reduced 24 h morphine consumption [mean difference (MD): -7.2 mg; 95% confidence interval (CI): -11.4, -3.0 mg; seven studies] and prolonged time to first analgesic request (MD: 135 min; 95% CI: 102, 168 min; 16 studies) when compared with the control group. Neuraxial clonidine increased intraoperative hypotension [odds ratio (OR): 2.849; 95% CI: 1.363, 5.957], intraoperative sedation (OR: 2.355; 95% CI: 1.016, 5.459), but reduced the need for intraoperative analgesic supplementation (OR: 0.224; 95% CI: 0.076, 0.663). The effect of clonidine on intraoperative bradycardia, intraoperative and postoperative nausea and vomiting, postoperative sedation, and pruritus were inconclusive. Neuraxial clonidine did not negatively impact neonatal umbilical artery pH or Apgar scores. This review demonstrates that neuraxial clonidine enhances postoperative analgesia in women having Caesarean section with neuraxial anaesthesia, but this has to be balanced against increased maternal adverse effects.

Intrathecal magnesium sulfate does not reduce the ED50 of intrathecal hyperbaric bupivacaine for cesarean delivery in healthy parturients: a prospective, double blinded, randomized dose-response trial using the sequential allocation method

Background

Addition of intrathecal magnesium sulfate to local anesthetics has been reported to potentiate spinal anesthesia and prolong analgesia in parturients. The current study was to determine whether intrathecal magnesium sulfate would reduce the dose of hyperbaric bupivacaine in spinal anesthesia with bupivacaine and sufentanil for cesarean delivery.

Methods

Sixty healthy parturients undergoing scheduled cesarean delivery were randomly assigned to receive spinal anesthesia with 0.5% hyperbaric bupivacaine and 5 μg sufentanil with either 0.9% sodium chloride (Control group) or 50% magnesium sulfate (50 mg) (Magnesium group). Effective anesthesia was defined as a bilateral T₅ sensory block level achieved within 10 min of intrathecal drug administration and no additional epidural anesthetic was required during surgery. Characteristic of spinal anesthesia and the incidence of side effects were observed. The ED₅₀ for both groups was calculated using the Dixon and Massey formula.

Results

There was no significant difference in the ED₅₀ of bupivacaine between the Magnesium group and the Control group (4.9 mg vs 4.7 mg) (P = 0.53). The duration of spinal anesthesia (183 min vs 148 min, P < 0.001) was longer, the consumption of fentanyl during the first 24 h postoperatively (343 μg vs 550 μg, P < 0.001) was lower in the Magnesium group than that in the Control group.

Conclusions

Intrathecal magnesium sulfate (50 mg) did not reduce the dose requirement of intrathecal bupivacaine, but can extend the duration of spinal anesthesia with no obvious additional side effects.

Trial registration

This study was registered with Chinese Clinical Trial Registry (ChiCTR) on 15 Jul. 2014 and was given a trial ID number ChiCTR-TRC-14004954.

Neuroprotection and neurotoxicity in the developing brain: an update on the effects of dexmedetomidine and xenon

Growing and consistent preclinical evidence, combined with early clinical epidemiological observations, suggest potentially neurotoxic effects of commonly used anesthetic agents in the developing brain. This has prompted the FDA to issue a safety warning for all sedatives and anesthetics approved for use in children under three years of age. Recent studies have identified dexmedetomidine, the potent α2-adrenoceptor agonist, and xenon, the noble gas, as effective anesthetic adjuvants that are both less neurotoxic to the developing brain, and also possess neuroprotective properties in neonatal and other settings of acute ongoing neurologic injury. Dexmedetomidine and xenon are effective anesthetic adjuvants that appear to be less neurotoxic than other existing agents and have the potential to be neuroprotective in the neonatal and pediatric settings. Although results from recent clinical trials and case reports have indicated the neuroprotective potential of xenon and dexmedetomidine, additional randomized clinical trials corroborating these studies are necessary. By reviewing both the existing preclinical and clinical evidence on the neuroprotective effects of dexmedetomidine and xenon, we hope to provide insight into the potential clinical efficacy of these agents in the management of pediatric surgical patients.

Effect of adding clonidine to intrathecal bupivacaine on the quality of subarachnoid block: A prospective randomized double-blind study

Context:

The purpose of adding an adjuvant to local anesthetic in a central neuraxial blockade is to augment the desirable pharmacological actions of the agent and/or to minimize its undesirable pharmacological effects. Clonidine is an alfa-2 receptor agonist which has gained popularity in recent times as an adjuvant in spinal anesthesia.

Aims:

To evaluate the influence of clonidine on the hemodynamic stability and the duration of anesthesia when added to intrathecal hyperbaric bupivacaine.

Settings and Design:

Prospective randomized double blind study.

Subjects and Methods:

Fifty patients scheduled for spinal anesthesia were randomized into two Groups A and B with 25 in each. Group A patients received 3 ml 0.5% heavy bupivacaine + 30 μg (0.2 ml) clonidine and Group B patients received 3 ml 0.5% heavy bupivacaine + 0.2 ml normal saline in the subarachnoid space. The blood pressure and heart rate were closely monitored. The time for attaining peak sensory block, time for two segment regression, decrease in the heart rate, total requirement of mephentermine to counter the hypotension, and the number of patients requiring mephentermine in each group was tabulated and analyzed.

Statistical Analysis Used:

Descriptive and inferential statistical methods were used to analyse the data. The power of the study was calculated using online power calculator for two independent sample study.

Results:

The time for attaining peak sensory block was similar in both the groups. The time for two segment regression in Group A was 62.6 min and in Group B was 38.08 min. Twelve percent of patients in Group A and 52% of patients in Group B required mephentermine with the mean consumption being 0.72 mg in Group A and 5.65 mg in Group B.

Conclusions:

Addition of low-dose clonidine to intrathecal bupivacaine not only prolonged the duration of spinal anesthesia but also provided a stable intraoperative hemodynamic profile.

Combined spinal-epidural versus epidural analgesia for labor and delivery

The rapid onset of analgesia and improved mobility with combined spinal-epidural (CSE) techniques has been associated with a higher degree of maternal satisfaction compared with conventional epidural analgesia. However, controversy exists in that initiation of labor analgesia with a CSE may be associated with an increased risk for nonreassuring fetal status (ie, fetal bradycardia) and a subsequent need for emergent cesarean delivery. Overall, both epidural and CSE techniques possess unique risk/benefit profiles, and the decision to use one technique rather than the other should be determined based on individual patient and clinical circumstances.

Effects of imidazoline I₂ receptor ligands on morphine- and tramadol-induced antinociception in rats

Currently available analgesics cannot meet the increasing clinical needs and new analgesics with better therapeutic profiles are in great demand. The imidazoline I₂ receptor is an emerging drug target for analgesics. However, few studies have examined the effects of selective I₂ receptor ligands on the antinociceptive activity of opioids. This study examined the antinociceptive effects of the opioids morphine (0.1-10 mg/kg) and tramadol (3.2-56 mg/kg), the nonselective I₂ receptor ligand agmatine (10-100 mg/kg), and the selective I₂ receptor ligands 2-(2-benzofuranyl)-2-imidazoline hydrochloride (2-BFI; 1-10 mg/kg) and 2-(4, 5-dihydroimidazol-2-yl) quinoline hydrochloride (BU224; 1-10mg/kg), alone and in combination, in a warm water tail withdrawal procedure in rats. Morphine and tramadol but not agmatine, 2-BFI or BU224 increased tail withdrawal latency in a dose-related manner at 48°C water. Agmatine and 2-BFI but not BU224 dose-dependently enhanced the antinociceptive effects of morphine and tramadol, shifting the dose-effect curves of morphine and tramadol leftward. The enhancement of agmatine and 2-BFI on morphine and tramadol antinociception was prevented by BU224. These results, combined with the fact that BU224 and 2-BFI share similar behavioral effects under other conditions, suggest that BU224 has lower efficacy than 2-BFI at I₂ receptors, and that the enhancement of opioid antinociception by I₂ receptor ligands depends on their efficacies.

Evaluation of analgesic effects of intrathecal clonidine along with bupivacaine in cesarean section

Aims and Context:

The objective of the present study was to evaluate the analgesic and adverse effects of intrathecal clonidine with hyperbaric bupivacaine in spinal anesthesia.

Settings and Design:

Randomized single blind trial.

Methods:

210 ASA I-II pregnant females undergoing emergency cesarean section were randomized in a single-blind fashion to one of the three groups. In group I (n=70) patients received 12.5 mg of 0.5% hyperbaric bupivacaine intrathecally. In group II (n=70) patients received intrathecal mixture of 0.5% hyperbaric bupivacaine (8 mg) and clonidine 50 μg. In group III (n=70), patients received 0.5% hyperbaric bupivacaine (10 mg) intrathecally along with 50 μg of clonidine.

Statistical Analysis Used:

Groups were compared using one-way ANOVA with the Bonferroni multiple comparison post hoc test. The proportion of adverse events was compared using the chi-square test (χ² =57.2410).

Results:

On adding 50 μg clonidine, we were able to reduce intrathecal dose of bupivacaine for cesarean section to 8 mg. Patients receiving intrathecal clonidine along with bupivacaine had significantly long lasting analgesia with lower bupivacaine dose [246.21±5.15 min. (group II) vs 146.0±4.55 min (group I), P=0.021; 95% confidence interval: 238.01-257.40, group II and 134.99-157.0 group I].

Conclusions:

Addition of intrathecal clonidine causes some sedation in the postoperative period, but it provides adequate analgesia and motor paralysis at lower dose of bupivacaine. It also significantly prolongs postoperative pain relief.

Modern neuraxial labor analgesia: options for initiation, maintenance and drug selection

In the present review we outline the state-of-the-art of neuraxial analgesia. As neuraxial analgesia remains the gold standar of analgesia during labor, we review the most recent literature on this topic. The neuraxial analgesia techniques, types of administration, drugs, adjuvants, and adverse effects are investigated from the references. Most authors would agree that central neuraxial analgesia is the best form to manage labor pain. When neuraxial analgesia is administered to the parturient in labor, different management choices must be made by the anesthetist: how will we initiate analgesia, how will analgesia be maintained, which local anesthetic will we use for neuraxial analgesia and which adjuvant drugs will we combine? The present manuscript tries to review the literature to answer these questions.

Effects of subchronic versus acute in utero exposure to dexmedetomidine on foetal developments in rats

Dexmedetomidine is a highly selective and specific alpha-2 adrenergic agonist with sedative, analgesic and sympathetic activities. This study was undertaken to investigate the effects of in utero exposure of dexmedetomidine on foetal development and postnatal behaviour in the offspring. Pregnant Sprague-Dawley rats were chronically treated with dexmedetomidine (0, 5, 10 and 20 microg/kg, subcutaneously) daily from gestation day 7 to day 19. Another group of animals received only a single acute dose of dexmedetomidine (20 microg/kg) on gestational day 19 to mimic a model for systemic analgesia during labour. Administration of dexmedetomidine did not affect the frequency of implantations. Chronic administration of 10 and 20 microg/kg of dexmedetomidine significantly reduced the body weight and crown-rump length of pups, whereas a single acute dose (20 microg/kg) did not affect these parameters. None of the pups exhibited any external malformations or skeletal abnormalities irrespective of treatment assigned. All the pups showed a normal postnatal weight gain during the developmental phase. No significant differences were observed among any of the groups with respect to behavioural performances of offspring in beam balance, grip strength and inclined plane tests as well as motor activity. In conclusion, acute exposure to dexmedetomidine at the anticipated delivery time does not exert any adverse effects on perinatal morphology of pups, their birth weight, crown-rump length, physical growth and postnatal behavioural performances. Since this study was conducted in rats, its clinical relevance in human beings remains to be unclear and warrants further studies.

Labor analgesia with ropivacaine added to clonidine: a randomized clinical trial

CONTEXT AND OBJECTIVE

Previous studies have led to speculation that the association between ropivacaine and clonidine might be more effective than ropivacaine alone. We examined the maternal-fetal effects of two pharmacological approaches: a low dose of ropivacaine or a lower dose of ropivacaine plus clonidine for epidural analgesia during labor.

DESIGN AND SETTING

Prospective study at Department of Anesthesiology, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista.

METHODS

Thirty-two pregnant women in American Society of Anesthesiologists physical status I and II randomly underwent epidural analgesia using 15 ml of ropivacaine 0.125% (R group) or 15 ml of ropivacaine 0.0625% plus 75 microg clonidine (RC group). Pain intensity, sensory block level, latency time, motor block intensity, duration of labor analgesia and duration of epidural analgesia were evaluated. The newborns were evaluated using Apgar scores and the Amiel-Tison method (neurological and adaptive capacity score).

RESULTS

There were no statistically significant differences between the groups regarding pain score, sensory block level, duration of epidural analgesia or Apgar score. The latency time, duration of labor analgesia and motor block were R group < RC group. The half-hour and two-hour neurological and adaptive capacity scores were higher in the R group. All of the R group newborns and 75% of the RC group newborns were found to be neurologically healthy at the 24-hour examination.

RESULTS

There were no statistically significant differences between the groups regarding pain score, sensory block level, duration of epidural analgesia or Apgar score. The latency time, duration of labor analgesia and motor block were R group < RC group. The half-hour and two-hour neurological and adaptive capacity scores were higher in the R group. All of the R group newborns and 75% of the RC group newborns were found to be neurologically healthy at the 24-hour examination.

CONCLUSION

Both low-dose ropivacaine and a lower dose plus clonidine relieved maternal pain during obstetric labor. Newborns of mothers who received only ropivacaine showed better neurological and adaptive capacity scores.

[30 microg intrathecal clonidine prolongs labour analgesia, but increases the incidence of hypotension and abnormal foetal heart rate patterns]

OBJECTIVE

To assess the efficacy of spinal clonidine combined with bupivacaine and sufentanil and its effects on maternal and foetal outcome.

STUDY DESIGN

Prospective double-blind randomized study.

PATIENTS AND METHODS

One hundred and five patients requesting labour analgesia had combined spinal epidural analgesia with intrathecal bupivacaine 2.5 mg and were randomly assigned to receive in addition either sufentanil 5 microg (S5), sufentanil 5 microg and clonidine 30 microg (C30), or sufentanil 10 microg (S10). Onset time, duration of analgesia, visual analogue scores, blood pressure, ephedrine requirements, heart rate, nausea, pruritus, sedation, motor block, foetal heart rate abnormalities, mode of delivery and Apgar scores were recorded.

RESULTS

Mean duration of spinal analgesia was significantly longer in patients receiving spinal clonidine compared to patients in S5 group (144+/-61 min versus 95+/-37 min). The onset time of analgesia was significantly shorter in S10 group (3+/-1 min) versus C30 group (4+/-1 min) and S5 group (4+/-1 min) (P=0.002). Hypotension was significantly more frequent in C30 group (29 versus 3% and 3% in S5 and S10 groups) (p=0,001). Foetal heart rate abnormalities and sedation were also significantly more frequent in C30 group. Mode of delivery (spontaneous, instrumental or caesarean delivery) and Apgar scores were unaffected by clonidine treatment.

CONCLUSION

Intrathecal clonidine 30 mug prolongs analgesia. However, it increases the incidence of hypotension, and abnormal foetal heart rate patterns. Thus, this study confirms that the use of 30 mug intrathecal clonidine for labour analgesia is not recommended.

The use of neuraxial adjuvant drugs (neostigmine, clonidine) in obstetrics

PURPOSE OF REVIEW

Neuraxial adjuvant drugs are used to improve analgesia and to decrease complications associated with a high dose of a single drug. Opioids are used in routinely, but alpha2-agonists, such as clonidine or cholinesterase inhibitors (neostigmine), have also been used for labour analgesia or to relieve pain following caesarean section. Both drugs possess a common mechanism of action that can be beneficial.

RECENT FINDINGS

Small doses of intrathecal clonidine (30 microg), combined with local anaesthetics and opioids, prolong labour analgesia. Hypotension can occur and must be promptly treated by ephedrine to avoid fetal side effects. Epidural clonidine (60 to 75 microg) produces prolonged analgesia from local anaesthetics and opioids and allows a ropivacaine sparing effect. Intrathecal neostigmine has analgesic properties, but its gastro-intestinal side effects contraindicate its clinical use. Epidural neostigmine, combined with sufentanil or clonidine, initiates labour analgesia (minimum 6 to 7 microg/kg; 500 microg) without side effects, however, and allows a 'mobile epidural'. Epidural and spinal clonidine can be used to improve postcaesarean section analgesia. Epidural neostigmine at the doses studied produces modest analgesia following caesarean section.

SUMMARY

Co-administration of neuraxial drugs may enhance analgesia and reduce the side effects of each drug. Clonidine and neostigmine may be used in obstetrics, under some conditions.

Neuraxial analgesia and fetal bradycardia

PURPOSE OF REVIEW

To review the most recent data on labor analgesia and the risk of fetal heart rate changes.

RECENT FINDINGS

Fetal heart rate changes are more common with intrathecal opioids, especially when high doses are used. Intrathecal clonidine seems to increase the risk of hypotension and fetal heart rate changes. Intravenous fluid preloading is useful in high-dose labor epidural analgesia, but its use remains controversial with low-dose techniques of epidural analgesia. Despite the potential of neuraxial analgesia to induce fetal bradycardia, neonatal outcome is usually reassuring.

SUMMARY

Despite the potential of neuraxial analgesia to cause fetal heart rate problems, neuraxial analgesia is the most effective and safest form of labor analgesia. Specific techniques of labor analgesia, such as high-dose spinal opioids or intrathecal clonidine, must be avoided based on the most recent evidence. Maternal and neonatal outcome is good following regional analgesia.