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The effects of adding epinephrine to ropivacaine for popliteal nerve block on the duration of postoperative analgesia: a randomized controlled trial.

Schoenmakers KP, Fenten MG, Louwerens JW, Scheffer GJ, Stienstra R - BMC Anesthesiol (2015)

Bottom Line: Both technique and type of local anesthetic used, either with or without adjuncts, may result in different duration times of the block.The results of this study did not show any significant increase in the duration of postoperative analgesia by adding epinephrine to ropivacaine for popliteal nerve block.The absence of a significant difference can also be the result of a type II error caused by a large variation in the individual TTFR.

View Article: PubMed Central - PubMed

Affiliation: Department of Anaesthesiology, Post box 9011, 6500 GM, Nijmegen, The Netherlands. k.schoenmakers@maartenskliniek.nl.

ABSTRACT

Background: Duration of peripheral nerve blocks depends on multiple factors. Both technique and type of local anesthetic used, either with or without adjuncts, may result in different duration times of the block. The purpose of the present study was to compare the duration of postoperative analgesia of 30 mL ropivacaine 0.75 % with or without epinephrine for popliteal sciatic nerve block.

Methods: Thirty-eight patients were included to receive ultrasound guided continuous popliteal nerve block with ropivacaine 0.75 % either without (ROPI) or with epinephrine 5 μg/mL (ROPI-EPI) for ankle fusion, subtalar fusion, or a combination of both. The primary outcome parameter was the duration of postoperative analgesia as reflected by the time to first request for postoperative analgesia (TTFR) through the popliteal nerve catheter. Secondary outcome measures included the onset of sensory and motor block and NRS score for pain at rest and during movement.

Results: Thirty patients, 15 in each group, were studied. Eight patients were withdrawn because of specific withdrawal criteria described in the protocol and replaced according to their group allocation. Median [interquartile range] TTFR was 463 [300-1197] min and 830 [397-1128] min for the ROPI vs ROPI-EPI group respectively. Hodges Lehman median difference between groups was 71 min (95 % CI -415 - 473 min). There was no difference in any clinical outcome measure between the groups.

Conclusion: The results of this study did not show any significant increase in the duration of postoperative analgesia by adding epinephrine to ropivacaine for popliteal nerve block. This may be due to the intrinsic vasoconstrictive properties of ropivacaine. The absence of a significant difference can also be the result of a type II error caused by a large variation in the individual TTFR.

Trial registration: Trial register.nl identifier: NTR3330 , keyword TTFR.

No MeSH data available.


Related in: MedlinePlus

Consort flowchart of patients enrolled in the study
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Fig1: Consort flowchart of patients enrolled in the study

Mentions: In order to study 15 patients in each group, 38 patients were included in the study protocol between July 2012 and March 2013. A Consort flowchart is shown in Fig. 1. Five patients in the ROPI group and three in the ROPI-EPI group were withdrawn on account of specific withdrawal criteria described in the protocol. These included absence of the primary outcome parameter: no request for postoperative analgesia at t = 48 h and absence of sensory sciatic nerve block (one in each group); pain requiring therapy in the distribution of the sciatic nerve upon arrival at the recovery directly postoperatively (block failure; three in the ROPI group, one in the ROPI-EPI group); and start of surgery before preoperative block assessment could be made (one in each group). The latter two patients were withdrawn from the study because there was no time for the sciatic nerve block to develop and the attending anesthesiologists were allowed to use long acting opioids at their own descretion. There were no significant differences in patient characteristics between the two groups (Table 1). None of the patients showed signs of local anaesthetic systemic toxicity or inadvertent intravascular injection of epinephrine (such as rise in heart rate, systolic blood pressure or flushing).Fig. 1


The effects of adding epinephrine to ropivacaine for popliteal nerve block on the duration of postoperative analgesia: a randomized controlled trial.

Schoenmakers KP, Fenten MG, Louwerens JW, Scheffer GJ, Stienstra R - BMC Anesthesiol (2015)

Consort flowchart of patients enrolled in the study
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4496888&req=5

Fig1: Consort flowchart of patients enrolled in the study
Mentions: In order to study 15 patients in each group, 38 patients were included in the study protocol between July 2012 and March 2013. A Consort flowchart is shown in Fig. 1. Five patients in the ROPI group and three in the ROPI-EPI group were withdrawn on account of specific withdrawal criteria described in the protocol. These included absence of the primary outcome parameter: no request for postoperative analgesia at t = 48 h and absence of sensory sciatic nerve block (one in each group); pain requiring therapy in the distribution of the sciatic nerve upon arrival at the recovery directly postoperatively (block failure; three in the ROPI group, one in the ROPI-EPI group); and start of surgery before preoperative block assessment could be made (one in each group). The latter two patients were withdrawn from the study because there was no time for the sciatic nerve block to develop and the attending anesthesiologists were allowed to use long acting opioids at their own descretion. There were no significant differences in patient characteristics between the two groups (Table 1). None of the patients showed signs of local anaesthetic systemic toxicity or inadvertent intravascular injection of epinephrine (such as rise in heart rate, systolic blood pressure or flushing).Fig. 1

Bottom Line: Both technique and type of local anesthetic used, either with or without adjuncts, may result in different duration times of the block.The results of this study did not show any significant increase in the duration of postoperative analgesia by adding epinephrine to ropivacaine for popliteal nerve block.The absence of a significant difference can also be the result of a type II error caused by a large variation in the individual TTFR.

View Article: PubMed Central - PubMed

Affiliation: Department of Anaesthesiology, Post box 9011, 6500 GM, Nijmegen, The Netherlands. k.schoenmakers@maartenskliniek.nl.

ABSTRACT

Background: Duration of peripheral nerve blocks depends on multiple factors. Both technique and type of local anesthetic used, either with or without adjuncts, may result in different duration times of the block. The purpose of the present study was to compare the duration of postoperative analgesia of 30 mL ropivacaine 0.75 % with or without epinephrine for popliteal sciatic nerve block.

Methods: Thirty-eight patients were included to receive ultrasound guided continuous popliteal nerve block with ropivacaine 0.75 % either without (ROPI) or with epinephrine 5 μg/mL (ROPI-EPI) for ankle fusion, subtalar fusion, or a combination of both. The primary outcome parameter was the duration of postoperative analgesia as reflected by the time to first request for postoperative analgesia (TTFR) through the popliteal nerve catheter. Secondary outcome measures included the onset of sensory and motor block and NRS score for pain at rest and during movement.

Results: Thirty patients, 15 in each group, were studied. Eight patients were withdrawn because of specific withdrawal criteria described in the protocol and replaced according to their group allocation. Median [interquartile range] TTFR was 463 [300-1197] min and 830 [397-1128] min for the ROPI vs ROPI-EPI group respectively. Hodges Lehman median difference between groups was 71 min (95 % CI -415 - 473 min). There was no difference in any clinical outcome measure between the groups.

Conclusion: The results of this study did not show any significant increase in the duration of postoperative analgesia by adding epinephrine to ropivacaine for popliteal nerve block. This may be due to the intrinsic vasoconstrictive properties of ropivacaine. The absence of a significant difference can also be the result of a type II error caused by a large variation in the individual TTFR.

Trial registration: Trial register.nl identifier: NTR3330 , keyword TTFR.

No MeSH data available.


Related in: MedlinePlus