Epidural Pain Relief Research Articles

Combined Programmed Intermittent Bolus and Patient-Controlled Bolus Is a More Favorable Setting for Epidural Pain Relief Than Continuous Infusion.

Epidural analgesia is a suitable and effective treatment for labor pain. However, the preferable modality setting for delivery remains debatable. This study adopted a programmed intermittent epidural bolus (PIEB) setting in conjunction with a patient-controlled epidural analgesia (PCEA) setting to improve the quality of labor analgesia and reduce the number of medical staff. We conducted a prospective observational analysis of primigravida parturients scheduled for spontaneous labor, which required epidural analgesia for painless labor. A total of 483 healthy primigravida parturients with singleton pregnancies were included in this cohort; 135 nulliparous patients were assigned to the continuous infusion setting (CEI) group and 348 to the PIEB + PCEA group. Compared to the CEI setting, the PIEB + PCEA setting significantly reduced the manual rescue by the clinician, extended the time required for the first manual rescue dose, and acclaimed good maternal satisfaction. The use of the CEI mode increased for poor performance requiring more than two rescues with an odds ratio of 2.635 by a binary logistic regression analysis. Using the PIEB + PCEA setting as the maintenance infusion had a longer duration for the first requested manual rescue, fewer manual rescue boluses, excellent satisfaction, and no significant increase in adverse events compared to the CEI setting.

Comparison of Chloroprocaine Versus Lidocaine With Epinephrine, Sodium Bicarbonate, and Fentanyl for Epidural Extension Anesthesia in Elective Cesarean Delivery: A Randomized, Triple-blind, Noninferiority Study

(Anesth Analg. 2021;132: 666–675) Neuraxial analgesia is utilized in over 70% of labors in the United States. The authors of this study report a general consensus among their local and nonlocal peers that 3% chloroprocaine or CP, a local anesthetic with a quick preparation time, and 2% lidocaine, epinephrine, bicarbonate, and fentanyl, or LEBF, which needs additional preparation time, have similar onset times when used to convert epidural pain relief to epidural anesthesia for cesarean delivery (CD). To their knowledge, no study has confirmed this assumption. This study analyzes the onset times of CP and LEBF.

Determinants and Factors Associated with the Maintenance of Exclusive Breastfeeding after Hospital Discharge after Birth.

The benefits of exclusive breastfeeding are well known for both mother and baby. Despite this, rates of exclusive breastfeeding remain low. The present study aimed to determine the factors associated with the maintenance of this type of feeding after being discharged from the hospital after childbirth. A cross-sectional study was carried out with 1200 postpartum women in Spain. Sociodemographic, obstetric, and neonatal data were collected. Odds ratios (OR) and adjusted odds ratios (aOR) with 95% confidence intervals were calculated. Early breastfeeding initiation was identified as a factor that favors breastfeeding after hospital discharge (aOR: 2.47; 95%CI: 1.77, 3.45). Other factors that favor breastfeeding after discharge included the woman feeling very supported by her partner during pregnancy, childbirth, and the puerperium (aOR: 2.54; 95%CI:1.30, 5.00) and having previously breastfed other children (aOR: 1.97; 95%CI: 1.40, 2.76). Among the factors that hindered exclusive breastfeeding after discharge were multiple or twin pregnancies (aOR: 0.31; 95%CI 0.12, 0.83), induction of labor (aOR: 0.73; 95%CI: 0.53, 0.99), admission of the newborn to the neonatal intensive care unit (NICU) (aOR: 0.31; 95%CI 0.19, 0.52), using epidural pain relief during labor (aOR: 0.41; 95%CI: 0.27, 0.64), or a preterm newborn (aOR: 0.38; 95%CI: 0.21, 0.69). For all these reasons, it is essential to promote certain practices such as the early start of breastfeeding or the induced onset of labor, among others, in order to promote the maintenance of exclusive breastfeeding beyond hospital discharge after childbirth.

Perceived stress during labor and its association with depressive symptomatology, anxiety, and pain catastrophizing

Perceived stress is a dimension of the maternal stress response, however little data is available on perceived stress levels and its associated psychological risk factors during labor. In this secondary data analysis from a prospective study evaluating epidural regimens, we investigated the potential associations between depressive symptomatology, anxiety, and pain catastrophizing with perceived stress during labor. Healthy nulliparous adult women with term singleton pregnancies requesting for epidural analgesia in early labor were included. Assessments were administered after epidural analgesia and adequate pain relief were achieved. Perceived stress (Perceived Stress Scale, PSS, high PSS ≥ 16), depressive symptomatology (Edinburgh Postnatal Depression Scale, EPDS, high EPDS ≥ 10), and pain catastrophizing (Pain Catastrophizing Scale, PCS, high total PCS ≥ 25) were assessed as categorical variables. Additionally, anxiety (State-trait Anxiety Inventory, STAI), PCS total and its subscales (rumination, magnification and helplessness) were analyzed as continuous variables. Univariate and multivariable logistic regression models were used to identify factors associated with high PSS. Of 801 women included, 411 (51.9%) had high PSS. High EPDS (OR 2.16, 95%CI 1.36–3.44), increasing trait anxiety (OR 1.17, 95%CI 1.14–1.20), and increasing pain magnification (OR 1.12, 95%CI 1.05–1.19) were independently associated with high PSS. Depressive symptomatology, trait anxiety, and pain magnification were associated with perceived stress during labor, providing impetus for future research aimed at detecting and alleviating stress and its psychological or pain association factors.

Conversion of epidural analgesia to anesthesia for cesarean section

The frequency of cesarean sections is increasing from year to year, and the choice of optimal anesthetic management is important. Regional anaesthesia is the anaesthesia of choice for the cesarean section because it reduces maternal and neonatal risks. If an epidural pain relief of labor is performed, then this epidural catheter can be successfully used for conversion to epidural anaesthesia. The choice of drug for conversion depends on the degree of urgency; the highest rate of onset of anesthesia is shown by lidocaine with adjuvants (fentanyl, sodium bicarbonate). Conversion failure occurs in 0–21% of cases; the main risk factors for conversion failure are inadequate epidural analgesia and patient height. The management of failed conversion depends on the category of urgency and other factors and may include spinal, combined spinal-epidural, or general anesthesia

Maternal Fetal Health

Maternal Fetal Health

Comparison of the effectiveness between epidural methylprednisolone injection and intranasal calcitonin in reduction of back pain due to osteoporosis in postmenopausal patients: a randomized controlled trial

<p class="abstract"><strong>Background:</strong> Back pain is a common symptom in osteoporotic patients due to spinal compression fracture. Conservative management like nonsteroidal anti-inflammatory drugs and spinal orthoses has not been able to produce early pain relief. Intranasal calcitonin spray is considered effective because of its analgesic effect and increase in bone density. Role of epidural steroid injection for the treatment of osteoporotic back pain has not been studied. This study was conducted to find out the efficacy of epidural methylprednisolone injection in management of osteoporotic back pain in postmenopausal patients.</p><p class="abstract"><strong>Methods:</strong> Hundred patients with osteoporotic back pain in postmenopausal subjects were allocated into two groups: epidural and calcitonin. Epidural group received a single dose of interlaminar epidural steroid injection with methylprednisolone 80 mg. Calcitonin group received one puff of 200 IU given through one nostril followed to the other nostril the next day. Visual analogue scale for pain was the outcome measurement used. Pain relief at rest within 7 days was taken as early pain relief and within 21days as late pain relief. Pain relief after 21<sup>st</sup> day was considered no response. Test of significance was done by Kaplan Meier, Chi square and Fisher exact tests.</p><p class="abstract"><strong>Results:</strong> Out of 50 patients, 38 patients in the epidural group got pain relief within 7 days and the finding was statistically significant.</p><p class="abstract"><strong>Conclusions: </strong>Epidural methylprednisolone gives faster pain relief as early as the first post-injection day with a median value of 2 days against 15 days in case of intranasal calcitonin spray.</p>

Impact of video demonstration on willingness of pregnant women to receive epidural labor analgesia in a Nigerian hospital- An open label trial

Background: Labor pain is an inevitable experience for parturients with choice for labor analgesia depending on awareness, parturients' education, availability, cost and adverse effects of the analgesic materials. Methods: All pregnant women attending booking clinics in the obstetric units of our hospital were recruited into an open-label randomized control trial for a period of 3 months into either intervention or control group. The pregnant women in the intervention group were shown a video demonstration on epidural labor analgesia in addition to distribution of epidural information leaflets with verbal explanation on pain management in labour. The control group had the same exposure except the video demonstration. An interviewer semi-structured questionnaire was used to collect information on biodata, knowledge of pain management in labor, previous labor pain experience, willingness to receive epidural labor analgesia in the current pregnancy and factors associated with willingness to receive epidural labor analgesia. Data were analyzed using descriptive and inferential statistics with P < 0.05 accepted as statistically significant. Results: Out of the 199 expectant mothers that participated in the study, 95 (47.7%) were in the intervention group and 104 (52.3%) in the control group with 18 (18.9%) and 5 (4.8%) patients had prior knowledge of epidural labor analgesia respectively. A higher proportion of 41 (43.2%) of participants in the intervention group were willing to receive epidural analgesia in the current pregnancy, when compared with 13 (12.5%) in the control group (P = 0.001). Conclusion: Addition of video demonstration to epidural leaflet information with verbal explanation in the intervention group increased the willingness of pregnant women to request for epidural pain relief in the current pregnancy compared to the control group.

Epinephrine on Continuous Epidural Pain Relief in Labor

Epinephrine on Continuous Epidural Pain Relief in Labor

Maternal quality of life in routine labor epidural analgesia versus labor analgesia on request: results of a randomized trial

IntroductionThe purpose of this study was to evaluate the changes in maternal quality of life (QOL) from pregnancy to 6 weeks after delivery between routine labor epidural analgesia (EA) and pain relief on maternal request only.Methods\\Women delivering of a singleton in cephalic presentation beyond 36 + 0 weeks’ gestation were randomly allocated to EA as a routine during labor (routine EA group), or to any kind of analgesia on request only (control group). The Short Form health survey (SF-36) was used to assess women’s QOL before randomization, and 6 weeks postpartum. Data were analyzed according to the intention to treat principle.ResultsA total of 488 women were included, and antepartum as well as postpartum SF-36 questionnaires were filled in by 356 (73.0%) women, 176 (49.4%) in the routine EA group, and 180 (50.6%) in the control group. Changes from the QOL antepartum to the QOL 6 weeks postpartum were comparable between both groups, also in the subgroup of women in the control group who gave birth without any pain medication (n = 41, 22.8%). Maternal age and the incidence of adverse events related to EA, which were both higher in the routine EA group, had no influence on the changes in QOL. Differences in request for pain relief were comparable with other studies.ConclusionRoutine administration of EA during labor and pain relief on maternal request only are associated with comparable changes of women’s QOL antepartum to 6 weeks postpartum.

Variations in childbirth interventions in high-income countries: protocol for a multinational cross-sectional study

IntroductionThere are growing concerns about the increase in rates of commonly used childbirth interventions. When indicated, childbirth interventions are crucial for preventing maternal and perinatal morbidity and mortality, but their...

Place of Birth and Concepts of Wellbeing

AbstractThis article is based on analysis of a series of ethnographic case studies of midwifery units in England. Midwifery units1 are spaces that were developed to provide more home-like and less medically oriented care for birth that would support physiological processes of labour, women’s comfort and a positive experience of birth for women and their families. They are run by midwives, either on a hospital site alongside an obstetric unit (Alongside Midwifery Unit – AMU) or a freestanding unit away from an obstetric unit (Freestanding Midwifery Unit – FMU). Midwifery units have been designed and intended specifically as locations of wellbeing and although the meaning of the term is used very loosely in public discourse, this claim is supported by a large epidemiological study, which found that they provide safe care for babies while reducing use of medical interventions and with better health outcomes for the women. Our research indicated that midwifery units function as a protected space, one which uses domestic features as metaphors of home in order to promote a sense of wellbeing and to re-normalise concepts of birth, which had become inhabited by medical models and a preoccupation with risk. However, we argue that this protected space has a function for midwives as well as for birthing women. Midwifery units are intended to support midwives’ wellbeing following decades of professional struggles to maintain autonomy, midwife-led care2 and a professional identity founded on supporting normal, healthy birth. This development, which is focused on place of birth rather than other aspects of maternity care such as continuity, shows potential for restoring wellbeing on individual, professional and community levels, through improving rates of normal physiological birth and improving experiences of providing and receiving care. Nevertheless, this very focus also poses challenges for health service providers attempting to provide a ‘social model of care’ within an institutional context.1The term midwifery unit was adopted by the Birthplace research programme in place of the more popular term ‘birth centre’ to avoid ambiguity. In a midwifery unit care is not only provided by mid-wives but is also managed by midwives and does not normally include use of obstetric instruments or interventions. If a woman planning birth in a mid-wifery unit develops obstetric complications, or decides she wishes to have a medical intervention such as epidural pain relief, she is transferred for care to an obstetric unit. Some units called birth centres are not managed by midwives in this way.2Midwife-led care refers to care where the midwife, rather than an obstetrician or other professional is the lead professional, who takes responsibility for a woman’s maternity care through from pregnancy to postnatal. Following the Changing Childbirth report in 1993, this was re-established as the usual model for women classified as at low risk of pregnancy and birth complications.

Epidural pain relief versus systemic opioid-based pain relief for abdominal aortic surgery.

Epidural analgesia offers greater pain relief compared to systemic opioid-based medications, but its effect on morbidity and mortality is unclear. This review was originally published in 2006 and was updated in 2012 and again in 2016. To assess the benefits and harms of postoperative epidural analgesia in comparison with postoperative systemic opioid-based analgesia for adults undergoing elective abdominal aortic surgery. In the updated review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and five trial registers in November 2014, together with reference checking to identify additional studies. We included all randomized controlled trials comparing postoperative epidural analgesia and postoperative systemic opioid-based analgesia for adults who underwent elective open abdominal aortic surgery. Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information and data when required. We assessed the level of evidence according to the scale provided by the GRADE working group. We included 15 trials published from 1987 to 2009 with 1498 participants in this updated review. Participants had a mean age between 60.5 and 71.3 years. The percentage of women in the included studies varied from 0% to 28.1%. Adding an epidural to general anaesthesia for people undergoing abdominal aortic repair reduced myocardial infarction (risk ratio (RR) 0.54 (95% confidence interval (CI) 0.30 to 0.97); I(2) statistic = 0%; number needed to treat for one additional beneficial outcome (NNTB) 28 (95% CI 19 to 1423), visual or verbal analogical scale (VAS) scores up to three days after the surgery (mean difference (MD) -1.78 (95% CI -2.32 to -1.25); I(2) statistic = 0% for VAS scores on movement at postoperative day one), time to tracheal extubation (standardized mean difference (SMD) -0.42 (95% CI -0.70 to -0.15); I(2) statistic = 83%; equivalent to a mean reduction of 36 hours), postoperative respiratory failure (RR 0.69 (95% CI 0.56 to 0.85); I(2) statistic = 0%; NNTB 8 (95% CI 6 to 16)), gastrointestinal bleeding (OR 0.20 (95% CI 0.06 to 0.65); I(2) statistic = 0%; NNTB 32 (95% CI 27 to 74)) and time spent in the intensive care unit (SMD -0.23 (95% CI -0.41 to -0.06); I(2) statistic = 0%; equivalent to a mean reduction of six hours). We did not demonstrate a reduction in the mortality rate up to 30 days (RR 1.06 (95% CI 0.60 to 1.86); I(2) statistic = 0%). The level of evidence was low for mortality and time before tracheal extubation; moderate for myocardial infarction, respiratory failure and intensive care unit length of stay; and high for gastrointestinal bleeding and VAS scores. Epidural analgesia provided better pain management, reduced myocardial infarction, time to tracheal extubation, postoperative respiratory failure, gastrointestinal bleeding, and intensive care unit length of stay compared with systemic opioid-based drugs. For mortality, we did not find a difference at 30 days.

A Comparative Evaluation of Levobupivacaine Hydrochloride and Levobupivacaine Hydrochloride with Dexmedetomidine in Epidural Anesthesia and Postoperative Pain Relief undergoing Infraumbilical Surgeries

A Comparative Evaluation of Levobupivacaine Hydrochloride and Levobupivacaine Hydrochloride with Dexmedetomidine in Epidural Anesthesia and Postoperative Pain Relief undergoing Infraumbilical Surgeries

The stiff total knee replacement: Evaluation and treatment

Stiffness after TKR is a frustrating complication that has many possible causes. Though the definition of stiffness has changed over the years, most would agree that knee flexion of less than 75° and a 15° lack of extension constitutes stiffness. This presentation will focus on the potential causes of a stiff TKR, intraoperative tips to avoid this outcome, the postoperative evaluation and management, and the results of revision for a stiff TKR. The management of this potentially unsatisfying situation begins preoperatively with guidance of the patient’s expectations; it is well known that preoperative stiffness is strongly correlated with postoperative lack of motion. At the time of surgery, osteophytes must be removed and the components properly sized and aligned in all planes. Flexion/extension gaps must be equalized and soft-tissue balancing must be attained. One must avoid overstuffing the tibiofemoral and/or patellofemoral compartments with an inadequate bone resection. Despite these surgical measures and adequate pain control and rehabilitation, certain patients will continue to frustrate our best efforts. These patients likely have a biological predisposition for formation of scar tissue. Other potential causes for the stiff TKR include complex regional pain syndrome or joint infection. Close follow-up of a patient’s progress is crucial for the success in return of ROM. Should motion plateau early in the recovery phase, the patient should be evaluated for manipulation under anesthesia. At our institution, most manipulations are performed within 3 months postop under an epidural anesthetic; on occasion, patients will stay overnight for continuous epidural pain relief and immediate aggressive PT. The results of re-operations for a stiff TKR are variable due to the multiple etiologies. A patient with arthrofibrosis with a clear cause of stiffness, such as component malposition, malrotation, or overstuffing of the joint, has a greater chance of regaining motion than arthrofibrosis without a clear cause. Although surgical treatment with open arthrolysis, isolated component, or complete revision can be used to improve TKR motion, results have been variable and additional procedures are often necessary.

Occurrence and Predictors of Vacuum and Forceps Used Sequentially for Vaginal Birth

BackgroundSequential use of vacuum and obstetric forceps for vaginal delivery is associated with increased risks of adverse maternal and infant outcomes. MethodsWe conducted a retrospective cohort study to estimate the frequency of sequential use of vacuum and forceps for planned vaginal delivery and to identify predictors, using data collected in Ontario between 2004 and 2007. Multivariate logistic regression models were used to estimate the adjusted odds ratios and 95% confidence intervals of predictors of sequential use of vacuum and forceps. ResultsOf 186 988 pregnant women with a singleton, vertex presentation at term and a planned vaginal birth, 1062 (0.57%) required the sequential use of vacuum and forceps for delivery. The major predictors for sequential use of vacuum and forceps were mother’s primary language being other than English or French, nulliparity, a history of Caesarean section, dystocia, use of epidural or other pain relief, labour induction, labour augmentation, fetal macrosomia, and advanced gestational age. ConclusionIn this population-based study we found that 0.57% of planned vaginal births were delivered with sequential use of vacuum and obstetric forceps. Abnormal labour, fetal macrosomia, language barriers, and advanced gestational age are significant predictors of requiring this sequential use.

48 A PROSPECTIVE AUDIT OF ONE-HUNDRED PATIENTS PRESENTING FOR THORACIC EPIDURAL PAIN RELIEF FOR HEPATOBILIARY SURGERY

Background: There is a perception that epidurals provide the best pain relief for major abdominal surgery. Prospective trials comparing epidural anesthesia with i.v. narcotics have failed to show differences in complications. Using an epidural, however, is associated with significantly less pain during the first 3 postoperative days, decreases respiratory complications, and facilitates early ambulation. Aim: This was a prospective audit of 100 patients to assess the effectiveness of epidural analgesia for hepatobiliary surgery and review complications. Method: We prospectively audited 100 patients undergoing hepatobiliary surgery where thoracic epidural pain relief was offered as combined general and neuraxial anesthesia and continued for postoperative pain relief. Result: Four patients refused epidural and preferred morphine patient-controlled analgesia PCA. Two cases failed epidural placement and morphine PCA was given as an alternative. Ninety-four patients received thoracic epidural between T6 and T10. There was difficulty in placement in 8% of patients. Postoperatively, 2 patients had no sensory block and were given PCA morphine. All patients were followed up for 24 h postoperatively. There were significant interventions in the epidural management; 92% required at least one intervention. PCA morphine was added in 6 patients. Referred shoulder tip pain and discomfort from central venous neck lines required additional analgesia NSAIDs and paracetamol in 50% of patients. Patient satisfaction of analgesia was good, 92%. Hypotension requiring additional i.v. fluids occurred in 68% of patients. Conclusion: Thoracic epidural pain relief may be considered as the gold standard but it has significant failures in our series and additional pain relief was required. 47

Effect of combined spinal–epidural analgesia versus epidural analgesia on labor and delivery duration

Objective To determine whether combined spinal–epidural analgesia (CSEA) can decrease the known epidural effect of lengthening delivery. Methods Between April and May 2010, 144 women undergoing childbirth in hospital with epidural pain relief were randomized to receive either low-dose epidural analgesia (LEA) or CSEA. The spinal component included 2.5 mg of bupivacaine, 25 μg of fentanyl, and 200 μg of morphine. The epidural component of the CSEA procedure was started once pain returned. The primary outcome was total labor duration measured from the time of initiation of labor analgesia to delivery. Results The difference in duration between LEA (n = 72) and CSEA (n = 72) was 5 minutes for labor ( P = 0.82), 2 minutes for delivery ( P = 0.60), and 7 minutes for total labor duration ( P = 0.75). The combined group used less levobupivacaine ( P < 0.001) and had lower sensory blockade at the dermatomal level ( P = 0.037). Women in the CSEA group had a higher incidence of pruritus ( P = 0.002) and lightheadedness ( P = 0.02) during labor; and a higher incidence of pruritus ( P = 0.002), nausea–vomiting ( P = 0.026), and drowsiness ( P = 0.003) in the postpartum period. Conclusion As compared with LEA, CSEA did not shorten the duration of labor length; however, it did reduce levobupivacaine consumption and motor weakness.

Intrapartum risk factors for levator trauma

To determine intrapartum risk factors associated with levator trauma as identified by ultrasound imaging. A prospective observational study. Antenatal clinic of a tertiary hospital between May 2005 and February 2008. Nulliparous women (n=488) in their first ongoing pregnancy. An interview and four-dimensional translabial ultrasound was carried out between 36 and 38 weeks and again 3-4 months after delivery. Obstetric data were collected from the hospital database and/or participants' records. Levator macrotrauma ('avulsion') and microtrauma (irreversible overdistension). A total of 367 women (75%) returned for the postpartum assessment after normal vaginal delivery (n=187, 51%), vacuum (n=34, 9%), forceps (n=20, 5%) and caesarean section (n=126, 34%). Median follow up was 4.08 months (interquartile range 3.68-5.03 months). Levator avulsion was diagnosed in 32 (13%) of the women who delivered vaginally and in none of the caesarean section group regardless of indication. On multivariable regression forceps delivery was significantly associated with avulsion (P=0.01; OR 3.83; 95% CI 1.34-10.94). Using >20% peripartum increase in hiatal area on Valsalva as the cutoff, 28.5% of vaginally parous women were shown to have suffered irreversible overdistension. This was positively associated with the length of second stage (P=0.001; OR 1.01 per minute; 95% CI 1.0-1.02). Intrapartum epidural appeared to have a protective effect (P=0.03; OR 0.42; 95% CI 0.19-0.93). Levator trauma at the time of first delivery is associated with vaginal delivery, forceps and a longer second stage. Epidural pain relief may exert a protective effect.

Effects of induced hyperthermia on pharmacokinetics of ropivacaine in rats

Ropivacaine is a local anaesthetic used for epidural anaesthesia and postoperative pain relief. Hyperthermia is a very common sign of infection associated with variations in physiological parameters, which may influence drugs pharmacokinetics. The aim of this study was to determine the effects of induced hyperthermia on ropivacaine pharmacokinetics in rats. Two groups of six rats were given a single subcutaneous ropivacaine injection. Hyperthermia-induced animals were placed in a water bath to obtain a stable mean core temperature of 39.7 degrees C. After blood samples collection, ropivacaine serum concentrations and pharmacokinetic parameters were determined. Two other groups of six rats were sacrificed 30 min after ropivacaine injection to determine serum and tissues (brain and heart) concentrations. Our results (median +/- inter quartile range) reveal a significant increase of the total apparent clearance (0.0151 +/- 0.000800 L/min vs. 0.0134 +/- 0.00134 L/min), apparent volume of distribution (V(d)) (2.19 +/- 0.27 L vs. 1.57 +/- 0.73 L) and a significant decrease in exposure (488 +/- 50.6 mgxmin/L vs. 572 +/- 110 mgxmin/L) in induced-hyperthermia group. We observed a significant increase in brain ropivacaine concentration in hyperthermic rats (8.39 +/- 8.42 microg/g vs. 3.48 +/- 3.26 microg/g) and no significant difference between cardiac concentrations in the two groups (5.38 +/- 4.83 microg/g vs. 3.73 +/- 2.44 microg/g). Results suggest a higher tissular distribution of ropivacaine and an increase in blood-brain barrier permeability during hyperthermia. The hyperthermia-induced increase in V(d) could be responsible for an increase in cerebral ropivacaine toxicity. These experimental data provide a basis for future clinical investigations in relation to local anaesthetic use in hyperthermic patients.