Determination of the Optimal "Next Bolus" Interval for Programmed Intermittent Bolus Epidural Analgesia: A Randomized Controlled Trial
试验速览
- 阶段
- 不适用
- 状态
- 终止
- 入组人数
- 84
- 试验地点
- 2
- 主要终点
- Time to first administered Patient Controlled Epidural Analgesia (PCEA) request
研究概览
简要总结
The current standard of practice for the maintenance of epidural analgesia is through use of a continuous infusion pump. Enhanced technology now supports the use of programmed intermittent bolus (PIEB) administration. This novel drug delivery system provides small boluses of local anesthetic and opioid at programmed intervals. Several studies suggest that administration of PIEB allows a more extensive spread of local anesthetic in the epidural space and provides superior labour analgesia compared to traditional continuous epidural infusions. PIEB is associated with lower anesthetic consumption, a shorter second stage of labour and greater patient satisfaction.
The authors are focusing on a PIEB setting known as the "Next Bolus". "Next Bolus" (NB) determines when the first PIEB bolus is given after the initiation of the epidural and starting the PIEB pump. Currently we set this to be 15-45 minutes. In an attempt to optimize resources, authors hope to determine the optimal NB interval that will provide adequate analgesia but limit overall drug consumption. An optimally timed next bolus should minimize drug costs and limit nurse and physician intervention by decreasing the need for manual boluses.Increased local anesthetic consumption can cause undesirable side effects such as itchiness, decreased blood pressure and motor blockade. By assigning patients to receive the NB at 15, 30 or 45 minutes the authors hope to find the interval that provides analgesia while minimizing side effects, improving patient safety. If the bolus is given too late then there may be increased pain, less patient satisfaction, and the need for more analgesia in the form of Patient Controlled Epidural Anesthesia or a manual bolus.The authors hope that determining the NB will result in an institutional change to improve patient outcomes and facilitate knowledge transfer. This information will be the first available research to help guide other obstetrical centres using PIEB technology in determining the optimal NB interval.
详细描述
Background
Enhanced epidural pump technology now supports the use of automated or programmed intermittent bolus (PIB) administration. Anesthesiologists can now program pumps to deliver small, regularly timed intermittent boluses for maintenance of labour analgesia and specify "lockout" intervals to ensure patient safety.
Several studies suggest that administration of PIB may result in a more extensive spread of local anesthetic in the epidural space and provide superior labour analgesia compared to CEI. In a recently published systematic review by George et al. (1), PIB was associated with lower anesthetic consumption, a shorter second stage of labour and greater patient satisfaction compared to CEI (1).
The optimal PIB volume and dosing interval for programmed intermittent bolus has not been determined. A small volume with a short bolus interval may be associated with similar drawbacks as continuous infusion, while a large volume bolus interval may be associated with increased breakthrough pain and reduced patient satisfaction. Wong et al. showed that extending the PIB interval from 15 min to 60 min with a larger PIB volume (10 mL vs. 2.5 mL) results in decreased anesthetic consumption without affecting patient satisfaction (3). Until recently, there was not a pump that could provide PIB along with PCEA. Smith Medical now produces the CADD pump with this feature. It ensures that that there are specific limits set to not allow "stacking" of boluses and potentially unsafe administration of local anesthetics. This pump now has more variables to program and determine the quality of labour analgesia.
A variable that has not received any research attention is the "Next Bolus" (Figure 5). "Next Bolus" (NB) determines when the first PIB bolus is given after the initiation of the epidural and starting of the pump. Currently we set this to be 15-45 minutes depending on the clinician. Determining the optimal timing of the NB is important because if the bolus is given too late there may be increased pain and less patient satisfaction. This could lead to earlier initiation of PCEA, more frequent PCEA attempts and possibly the need for physician intervention for a manual bolus. As more local anesthetic is delivered, the patient may have a decrease in blood pressure or greater motor blockade (i.e. leg weakness) than desired.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Double (Participant, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •• American Society of Anesthesiologists (ASA) Physical Status I-II (ASA I - Healthy, ASA II - mild and controlled systemic disease)
- •Spontaneous labour
- •Nulliparous parturient
- •Single gestations ≥ 36 weeks
- •English speaking
- •Age 18-45 years
- •Vertex presentation
- •Requesting an epidural for labour analgesia
- •Cervical dilation less than 2 cm or greater than 6 cm at the time of initiation of neuraxial analgesia
排除标准
- •• Use of IV opioids within 1 hour of initiating the epidural
- •Use of nitrous oxide after initiating the epidural pump
- •Contraindications to neuraxial analgesia (i.e. coagulopathy, infection, neuropathy)
- •Abnormal spinal anatomy (i.e. scoliosis, spina bifida, spinal instrumentation)
- •Height < 5'0" or BMI ≥ 40 kg/m2
- •Chronic analgesics
- •Diseases of pregnancy (i.e. hypertension, preeclampsia, gestational diabetes)
- •Severe maternal cardiac disease
- •Known fetal anomalies /intrauterine fetal demise
- •Physical or psychiatric condition which may impair cooperation
研究组 & 干预措施
Next Bolus Interval 15 minutes
Next Bolus Interval 15 minutes
干预措施: Next Bolus Interval (Other)
Next Bolus Interval 30 minutes
Next Bolus Interval 30 minutes
干预措施: Next Bolus Interval (Other)
Next Bolus Interval 45 minutes
Next Bolus Interval 45 minutes
干预措施: Next Bolus Interval (Other)
结局指标
主要结局
Time to first administered Patient Controlled Epidural Analgesia (PCEA) request
时间窗: 360 minutes
The time from the start of the epidural pump to the first administered request for a PCEA bolus (in minutes).
次要结局
- Number of PCEA bolus attempts(360 minutes)
- Number of PCEA bolus received(360 minutes)
- Pain scores(360 minutes)
- Number of manual bolus doses administered by the anesthesiologist(360 minutes)
- Highest thoracic dermatome sensory level(360 minutes)
- Modified Bromage scores measured at 60, 120, 180, 240, 300, and 360 minutes(360 minutes)
- Occurrence of hypotension(360 minutes)
- Total local anesthetic consumption after pump initiation(360 minutes)
- Maternal satisfaction with labour analgesia(360 minutes)