Intermittent Epidural Injections Research Articles

Comparative Evaluation of Haemodynamic Effects of Continuous Versus Intermittent Epidural Injections of Bupivacaine with Fentanyl for Major Gynaecological Surgeries

Background: Epidural anaesthesia can be administered as single shot, intermittently, continuously or as patient controlled injection. Our study compared the intraoperative haemodynamic effects of continuous versus intermittent epidural injections of bupivacaine with fentanyl for major gynaecological surgeries.

Comparison of programmed intermittent epidural bolus injection and continuous epidural injection in controlling nighttime pain and improving sleep quality after thoracotomy.

Postoperative pain after open thoracotomy is known to be very severe and affects sleep quality. This study aimed to investigate the effects of a programmed intermittent epidural bolus injection versus continuous epidural injection for controlling nighttime pain and improving sleep quality after thoracotomy. Seventy-six patients scheduled for open thoracotomy for lung cancer or other lung diseases were enrolled. The participants were divided into 2 groups. Group A was continuously injected with 0.2% levobupivacaine at 1.1 mL/h, and group B was injected intermittently with 3 mL 0.2% levobupivacaine at 3 hours intervals through a thoracic epidural catheter via a programmed infusion pump. Within 48 hours after surgery, the degree of pain control using visual analog scale and the patients' sleep conditions on postoperative day (POD) 0 and 1 were evaluated, and other adverse events were investigated. On POD 1 night, the visual analog scale in group B showed lower than group A (P = .009). Comparison of time to fall asleep showed no differences between 2 groups. Total sleep time was no difference on POD 0 but was longer in group B than that in group A on POD 1 (P = .042). Awakening from sleep on POD 0 was lower in group B than that in group A (P = .033), and satisfaction with sleep quality on POD 0 was superior in group B compared to group A (P = .005). Postoperative nausea and vomiting occurred more frequently in group B than in group A (P = .018). The programmed intermittent epidural bolus technique of patient-controlled epidural analgesia reduces postoperative nighttime pain and improves sleep quality in patients undergoing thoracotomy for lung cancer or other lung diseases.

Comparison of the effects of programmed intermittent epidural bolus and continuous epidural infusion of ropivacaine for labor analgesia in latent phase

Objective To compare the efficacy of programmed intermittent epidural bolus and continuous epidural infusion of ropivacaine in labor analgesia. Methods From May 2014 to May 2017, 170 patients, 24-32 years, for full-term primipara in the Maternal and Child Health Care Hospital of Quzhou were selected as study objects, and they were randomly divided into intermittent epidural injection group(T group) and continuous epidural pump group(C group) by computer random software, with 85 cases in each group.All patients were epidurally injected 2% lidocaine 3mL and 0.2% ropivacaine 2mL at the opening of the uterus, less than 3cm.T group was given programmed intermittent epidural bolus 0.1% ropivacaine 6mL/h.C group was given continuous epidural infusion 0.1% ropivacaine 6mL/h.The pain of maternal(NRS score) and motor block situation of maternal (Bromage score) were monitored.The number of PCEA, PCEA pressure times, the rate of instrumental delivery and APGAR score were also recorded. Results The number of Bromage score≥2 in C group was higher than that of T group at 4-10h after labor analgesia (3 cases vs.11 cases, 3 cases vs.15 cases, 4 cases vs.17 cases, 4 cases vs.18 cases, 6 cases vs.19 cases, 6 cases vs.21 cases, 7 cases vs.22 cases; χ2=4.982, 8.947, 9.182, 10.230, 7.926, 9.907, 9.354, all P 0.05). The number of PCEA, PCEA pressure times and the rate of instrumental delivery in T group were lower than those in C group [8 cases vs.18 cases, 22 cases vs.41 cases, (3.5±1.5)times vs.(4.9±2.2)times; χ2=4.541, 9.104; t=2.666, all P 0.05). Conclusion Compared with continuous epidural infusion, programmed intermittent bolus of ropivacaine for labor analgesia exerts good analgesic effect, it has minor effects on exercise function and can decrease the rate of instrumental delivery. Key words: Parturition; Analgesia, obstetrical; Analgesia, epidural; Analgesia, patient-controlled; Programmed intermittent bolus; Continuous epidural infusion; Apgar score

Clinical observation of regular intermittent epidural injection combined with different puncture points in suppressing breakthrough pain in labour analgesia

The aim of the current study was to evaluate the clinical effects of the regular intermittent epidural injection combined with different puncture points (RIEI-dPP) in suppressing breakthrough pain during a labour analgesia. A total of 90 primipara were randomly divided into three groups (n = 30): Group L2–3 (A), Group L3–4 (B) and Group L4–5 (C). The analgesic pump parameters were set as: impact dose 8 mL, locking time 15 minutes, background dose 0, and the additional impact dose 8 mL after each hour intermittence. The pain’s visual analogue scale (VAS), breakthrough pain, maximum block segment, modified Bromage score, labour duration and the neonatal Apgar score were recorded and compared. Compared with the pre-analgesia time, the VAS scores were found to be significantly decreased in the three groups (p < .05), but there were significant differences among the three groups (p > .05). During analgesia, the maximum block segment in Group C was more significantly reduced than in the other two groups (p > .05), but there was no significant difference in the breakthrough pain among the three groups (p > .05). The comparison of other indexes among the three groups showed there was no significant difference (p > .05). RIEI-dPP at L2–3, L3–4 and L4–5 during labour analgesia can effectively inhibit breakthrough pain.Impact StatementWhat is already known on this subject? According to human anatomical features, the injection speed and capacity are the prerequisite for obtaining the ideal block range. Experiments confirm that a more uniform and wider drug distribution can be achieved by epidural intermittent rapid infusion with higher injection pressure than a continuous infusion with low injection pressure. Compared with the continuous epidural administration mode, the regular intermittent epidural injection mode can better inhibit breakthrough pain with a lower amount of anaesthetic.What the results of this study add? Similar labour analgesic effects can be achieved by regular intermittent epidural injection mode with different puncture points.What the implications are of these findings for clinical practice and/or further research? Compared with a continuous infusion, a regular intermittent epidural injection can achieve a more uniform drug distribution in the epidural space, so the block range can be more extensive, which can not only reduce the amount of anaesthetic but also effectively reduce the incidence of breakthrough pain. However, the selection of an intervertebral puncture site still lacks a uniform standard. The outcomes of this study can directly verify that regular intermittent epidural injection at L2–3, L3–4 and L4–5 can effectively inhibit breakthrough pain and achieve good analgesic effects, so selecting the intervertebral space with clear anatomical structure positioning and easier puncture pathway can benefit a labour analgesia.

Analysis of thoracic epidurography and correlating factors affecting the extent of contrast medium spread.

BackgroundThoracic epidural anesthesia is frequently used to maintain intraoperative and postoperative analgesia. Frequently, 3 ml of local anesthetic is used as a test dose, or for intermittent epidural injection. We assessed the extent of the spread of 3 ml of contrast medium in the thoracic epidural space and attempted to identify any correlating factors affecting the epidurography.MethodsA total of 70 patients were enrolled in the study, and thoracic epidural catheterizations were performed under fluoroscopic guidance. Using 3 ml of contrast medium, epidurography was evaluated to confirm the number of spinal segments covered by the contrast medium. Correlation analysis was performed between patient characteristics (sex, age, body mass index, weight, height, and location of catheter tip) and the extent of the contrast spread.ResultsThe mean number of vertebral segments evaluated by contrast medium was 7.9 ± 2.2 using 3 ml of contrast medium. The contrast spread in the cranial direction showed more extensive distribution than that in the caudal direction, with statistical significance (P < 0.01). Patient height demonstrated a negative correlation with the extent of distribution of contrast medium (r = −0.311, P < 0.05).ConclusionsThoracic epidurography using 3 ml of contrast medium results in coverage of a mean of 7.9 ± 2.2 spinal segments, with more extensive cranial spread, and patient height showed a weak negative correlation with the distribution of contrast medium.

An in vitro evaluation of the pressure generated during programmed intermittent epidural bolus injection at varying infusion delivery speeds

Study objectiveProgrammed intermittent bolus injection of epidural anesthetic solution results in decreased anesthetic consumption and better patient satisfaction compared with continuous infusion, presumably by better spread of the anesthetic solution in the epidural space. It is not known whether the delivery speed of the bolus injection influences analgesia outcomes. The objective of this in vitro study was to determine the pressure generated by a programmed intermittent bolus pump at 4 infusion delivery speeds through open-ended, single-orifice and closed-end, multiorifice epidural catheters. DesignIn vitro observational study. SettingNot applicable. PatientsNot applicable. InterventionsA CADD-Solis Pain Management System v3.0 with Programmed Intermittent Bolus Model 2110 was connected via a 3-way adapter to an epidural catheter and a digital pressure transducer. Pressures generated by delivery speeds of 100, 175, 300, and 400 mL/h of saline solution were tested with 4 epidural catheters (2 single orifice and 2 multiorifice). These runs were replicated on 5 pumps. Analysis of variance was used to compare the mean peak pressures of each delivery speed within each catheter group (single orifice and multiorifice). Main resultsThirty runs at each delivery speed were performed with each type of catheter for a total of 240 experimental runs. Peak pressure increased with increasing delivery speeds in both catheter groups (P<.001). Peak pressures were higher with the multiorifice catheter compared with the single-orifice catheter at all delivery speeds (P<.001, for all). ConclusionUsing a pump designed for programmed intermittent infusion boluses, the delivery speed of saline solution through epidural catheters was directly related to the peak pressures. Future work should evaluate whether differences in the delivery speed of anesthetic solution into the epidural space correlate with differences in the duration and quality of analgesia during programmed intermittent epidural bolus delivery.

The incidence of maternal fever during labor is less with intermittent than with continuous epidural analgesia: a randomized controlled trial

Background This prospective, randomized study was performed to see if intermittent labor epidural analgesia was protective against maternal intrapartum fever, compared to continuous epidural infusion. Methods Ninety-two healthy, term, nulliparous women in spontaneous labor were assigned to either intermittent (ILEA) or continuous labor epidural analgesia (CLEA), 46 in each group. In both groups, epidural analgesia was established with fentanyl 100 μg, and 8 mL of either 0.125% bupivacaine with fentanyl 0.0002%, or 0.1% ropivacaine with fentanyl 0.0002%. Maintenance in the CLEA group was with the same bupivacaine/fentanyl or ropivacaine/fentanyl solutions at 10-15 mL/h. In the ILEA group, additional boluses of the same solution were given as needed. Maternal tympanic temperature was measured before epidural insertion, 4-hourly during labor and 4 h post partum. Fever was defined as a temperature of ⩾38 °C. Newborn temperature was noted within 60 min of birth. Results The incidence of fever in ILEA was significantly lower at four hours (2/42, vs. 10/44 in CLEA, P = 0.036). No significant differences were detected at other time periods. Mean maternal temperatures did not differ between groups at any time. There were no differences in neonatal temperature or neonatal sepsis evaluation rate (CLEA vs. ILEA 0/46 vs. 2/43, P = 0.45). Conclusions Intermittent epidural injections appear to protect against intrapartum fever in the first 4 hours of labor analgesia, compared to continuous infusion. This may be due to intermittent partial recovery of heat loss mechanisms between injections. Neonatal sepsis evaluation rates were similar in the two groups.

Ambulatory epidural anesthesia and the duration of labor

Objectives: Ambulatory epidural analgesia has become a common option for women in labor in France. We tested the hypothesis that a method of epidural analgesia that allowed women to walk had specific advantages regarding mode of delivery, consumption of local anesthetic, oxytocin requirement, and labor duration. Methods: Two hundred and twenty-one women with uncomplicated pregnancies who presented in spontaneous labor between 36 and 42 weeks of gestation or who were scheduled for induced labor were randomly divided into two groups, ambulatory and non-ambulatory. All were given intermittent epidural injections of 0.1% ropivacaine with 0.6 μg/ml sufentanil for analgesia during labor ( P<0.05 was considered significant). None of the women had previous cesarean delivery. Results: There were no significant differences between the two groups in mode of delivery, consumption of local anesthetic, or oxytocin requirement. However, a significant difference was noted in labor duration (173.4±109.9 min vs. 236.4±130.6 min; P=0.001). Conclusions: Walking with ambulatory labor analgesia shortens labor duration but has no other effect on the progress and outcome of labor.

Labor pain relief using bupivacaine and sufentanil: Patient controlled epidural analgesia versus intermittent injections

Objectives To determine whether the use of patient-controlled epidural analgesia (PCEA) versus intermittent injections (CIT) resulted in local anesthetic dose reduction. Study Design PCEA and CIT using a mixture of 0.125% bupivacaine with sufentanil 1 or 0.75 μg/ml were compared in 60 and 195 parturients, respectively. Assessments included pain scores, local anesthetic consumption, degree of motor blockade, type of delivery and neonatal outcome. Statistical analysis was done using Student's t test and Chi-squares. Results PCEA and CIT provided effective analgesia during labor and delivery. A higher dose of opioid significantly reduced the use of local anesthetic solution in PCEA-patients. There was no difference in motor blockade, type of delivery and neonatal outcome. Conclusion Patient-controlled epidural analgesia is an effective, safe and acceptable alternative to conventional intermittent epidural injections for pain relief during labor and delivery.

Management of postoperative pain by continuous epidural infusion of analgesics

The anatomy and physiology of the epidural space and the mechanism of action, sites of action, and pharmacokinetics of analgesics administered by continuous epidural infusion are reviewed, and the efficacy, adverse effects, and postoperative indications for use of analgesics administered by this route are discussed. Narcotics selectively block pain conduction by occupying specific opiate receptors in the spinal cord. Local anesthetics provide analgesia by axonal membrane blockade; they also can produce nonselective sympathetic and somatic (sensory and motor) blockade in addition to analgesia. A narcotic-local anesthetic mixture should provide an additive analgesic effect, without an increase in the incidence of adverse effects. Comparative efficacy studies have shown that continuous epidural infusions of narcotics, local anesthetics, and narcotic-local anesthetic combinations, when used appropriately, may produce better analgesia than conventional bolus methods of pain relief. Continuous epidural infusions also offer a safety advantage over intermittent epidural injections because peak and trough levels of the analgesic agent are avoided. Adverse effects of epidurally administered narcotics include respiratory depression, pruritus, urinary retention, nausea and vomiting, and sedation. Adverse effects of epidurally administered local anesthetics include urinary retention, hypotension, numbness, motor weakness, tachyphylaxis, and, rarely, systemic toxicity. The cost of epidurally administered drugs is substantially higher than that for i.m. or i.v. narcotic analgesia, but this cost may be offset by other benefits such as a shorter hospital stay. Current studies suggest superior analgesia for the majority of surgical procedures with continuous epidural analgesia infusions compared with more traditional methods of providing analgesia.

Comparison of continuous epidural infusion and intermittent bolus epidural injection of local anesthetics for postoperative pain relief.

Comparison of continuous epidural infusion and intermittent bolus epidural injection of local anesthetics for postoperative pain relief.

Efficacy of Intermittent Epidural Morphine Following Posterior Spinal Fusion in Children and Adolescents

Postoperative pain is a distressing and disabling feature of scoliosis surgery. Epidural morphine has recently been advocated to reduce the frequency and severity of postoperative pain in adults. A retrospective study of 35 patients was conducted to determine whether epidural administration of morphine is useful in the management of postoperative pain in children and adolescents following posterior spinal fusion. The derived data included dose and frequency of narcotic administration on the day of surgery and during the subsequent three days. On the first postoperative day, the total morphine given averaged only 16.4 mg in patients receiving epidural morphine compared to 27 mg in those receiving only conventional parenteral morphine. Similar significant differences persisted through the second postoperative day. Intermittent epidural injection of small doses of morphine can give satisfactory and prolonged analgesia for early postoperative pain management.

Thoracic epidural anaesthesia in patients with unstable angina pectoris.

The effect of high thoracic epidural anaesthesia with intermittent epidural bolus injections of bupivacaine (2.5 or 5 mg ml-1) was studied in 28 patients with unstable angina pectoris. The majority of the patients had a history of previous acute myocardial infarction(s) and/or angina pectoris and severe coronary artery disease. All patients were treated with nitroglycerin infusion for greater than 24 h and were included in the study if they had chest pain, not caused by acute myocardial infarction, at bed rest or recurrent anginal pain at rest greater than 2 days after infarction. 4.4 +/- 0.3 ml of bupivacaine induced a blockade of the upper seven sympathetic segments (Th1-7) for 98 +/- 9 min. Heart rate decreased significantly from 70 +/- 3 to 64 +/- 3 beats min-1 while blood pressure was unaffected by thoracic epidural anaesthesia. In 27 patients (96%) the anaesthesia induced complete analgesia. Nitroglycerin infusion was discontinued definitely within 3 h in 26 patients (93%) and pain was thereafter controlled by means of thoracic epidural anaesthesia as the sole treatment in 23 patients (82%) and as the major treatment in 25 patients (89%). Twenty-one patients (75%) were fully mobilized and stabilized. Treatment with thoracic epidural anaesthesia lasted for 6.0 +/- 1.1 days. The number of daily epidural injections decreased significantly with time from 2.7 +/- 0.3 the first day to 0.9 +/- 0.3 the fourth day (P less than 0.01, n = 19). Two patients developed acute myocardial infarction during the anaesthesia treatment period, and one of these patients died.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Levels of Mepivacaine during Continuous Epidural Anesthesia

Venous blood concentrations of mepivacaine were measured in 30 patients during 5 hr of surgical anesthesia following either multiple epidural injections of mepivacaine with or without epinephrine or continuous epidural infusion of mepivacaine with epinephrine. Patients were divided into three groups: group 1 initially received 10 or 15 ml followed by 10 ml of 2% plain mepivacaine at 1-hr intervals; group 2 received 10 or 15 ml followed by 10 ml of epinephrine-containing 2% mepivacaine at 1-hr intervals; group 3 received 10 or 15 ml followed by a constant infusion of 10 ml/hr of epinephrine-containing 2% mepivacaine. There were no significant differences between groups 1 and 2, but the mean blood concentration was slightly lower for the first 3 hr in group 2 than group 1. The mean blood concentration of mepivacaine in group 3 remained significantly lower than the concentrations in groups 1 and 2 from 3.5 to 5 hr. These results demonstrate that the blood concentrations of mepivacaine are not reduced by the addition of epinephrine to mepivacaine solutions when intermittent epidural injections are repeated more than four times at 1-hr intervals, but that blood mepivacaine levels are reduced below levels seen with intermittent injections by the continuous epidural infusion of epinephrine-containing mepivacaine.

Variation in spread of analgesia and loss of temperature discrimination during intermittent postoperative epidural bupivacaine administration.

The proximal-distal and bilateral extent of analgesia and loss of temperature discrimination were assessed during the initial 34.5 h after major abdominal surgery in ten patients receiving intermittent epidural bupivacaine injections according to a fixed dose regimen. Segmental spread of loss of temperature discrimination was invariably larger than analgesia at all times. During the later postoperative period (24-34 h) a pronounced intra-individual variation in both proximal-distal and bilateral spread of analgesia was observed despite identical epidural injections of bupivacaine. This variation in extent of analgesia was observed during injections of both 0.5% and 0.25% bupivacaine. The explanation of this observation is unknown but it may be shifts in catheter position, a variable disposition of the local anaesthetic agent or changes in the epidural space rather than tachyphylaxis.

Plasma concentrations of lidocaine and its principal metabolites during intermittent epidural anesthesia.

Plasma concentration-time courses of lidocaine and its principal metabolites (monoethylglycinexylidide, MEGX, and glycinexylidide, GX) were studied during intermittent epidural injections of lidocaine HCl in eight female patients (ASA status 1). The initial dose (320-400 mg without epinephrine) followed by top-up injections of about 60% of the mean initial dose every 35-55 min resulted in a plasma accumulation of lidocaine: the peak concentration increased from 2.30 +/- 0.46 (mean +/- SD) microgram/ml following the first injection and 3.34 +/- 0.76 microgram/ml after the second, to 4.11 +/- 0.72 microgram/ml following the third. The maximum concentrations of MEGX and GX were 0.66 +/- 0.22 and 0.28 +/- 0.08 microgram/ml, respectively. A pharmacokinetic model could successfully fit the entire plasma concentration-time profile of lidocaine during repeated epidural injections (r2 = 0.886 to 0.983). Such pharmacokinetic variables as elimination half-life (t1/2, 2.33 +/- 0.43 h), apparent volume of distribution divided by bioavailability (Vd/F, 2.51 +/- 0.61 l/kg), and clearance divided by bioavailability (Cl/F, 11.65 +/- 1.21 ml X kg-1 X min-1) obtained from the female patients were in reasonable agreement with those reported from healthy females receiving the intravenous lidocaine HCl. A computer-aided simulation generated from using the mean kinetic data in a 50-kg woman predicted that plasma lidocaine concentration would reach the postulated toxic range (approximately equal to 6 microgram/ml) after the fourth supplementary dose under a similar dosing scheme as performed in this study. In conclusion, an accumulation of lidocaine in plasma occurs during a usual intermittent epidural dosing.(ABSTRACT TRUNCATED AT 250 WORDS)

Continuous Epidural Infusion of Morphine for Treatment of Pain after Thoracic Surgery

We evaluated postoperative pain relief and the incidence of side effects of three methods of thoracic epidural analgesia. Ninety patients, divided into three equal groups, received postoperative analgesia after thoracic surgery either as intermittent epidural injections of bupivacaine (25 mg/5 ml, 0.5% solution) as needed, or, intermittent epidural injections of morphine (5 mg/5 ml of normal saline, 0.1% solution) as needed, or continuous epidural infusion of morphine (0.1 mg, in 1 ml of normal saline) per hour supplemented with intravenous morphine (2 mg) upon request. Pain relief was evaluated by each patient on a pain scale visual analogue and by pain relief questionnaire for a period of 72 hr. Postoperative pain relief was achieved equally with these three methods of epidural analgesia in all patients with no significant difference between groups. Intermittent epidural injection of bupivacaine relieved pain for 4.9 +/- 1.9 (SD) hr/injection and was associated with urinary retention in all patients, with numbness and weakness of the hands in 12 patients, and with severe hypotension in 7 patients. Intermittent epidural injection of morphine relieved pain for 5.8 +/- 2.3 hr/injection and was associated with urinary retention in all patients, with pruritus in 12 patients, and with central narcosis and respiratory depression in 8 patients. Continuous epidural infusion of morphine with occasional intravenous morphine (2 mg) supplementation also effectively relieved postoperative pain and was associated with minimal systemic side effects. One patient complained of pruritus, and two patients developed urinary retention.(ABSTRACT TRUNCATED AT 250 WORDS)