Evidence map›Paper›PMID 34534232›Full record

Trial reportPloS one2021

The minimum effective concentration (MEC90) of ropivacaine for ultrasound-guided caudal block in anorectal surgery. A dose finding study.

Xuehan Li, Jun Li, Pei Zhang, Huifei Deng, Mingan Yang, Hongbo He, Rurong Wang

Open access · goldAbstract readRandomized Controlled Trial
PubMed Full text at PMC Publisher
In one paragraph

Trial report in PloS one, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 papers.

0numbers the graph read from it
0cells of the map it votes in
7citing papers in PubMed
1.5field-weighted citation impact, top 18% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

7 citing papers in PubMed, 12 citations in OpenAlex.

  1. Trial
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 2 institutions in 2 countries.

Xuehan LiDepartment of Anesthesiology, and Laboratory of Anesthesia and Intensive Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
Jun LiDepartment of Anesthesiology, and Laboratory of Anesthesia and Intensive Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
Pei ZhangDepartment of Anesthesiology, and Laboratory of Anesthesia and Intensive Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
Huifei DengDepartment of Anesthesiology, and Laboratory of Anesthesia and Intensive Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
Mingan YangDivision of Biostatistics & Epidemiology, School of Public Health, San Diego State University, San Diego, CA, United States of America.
Hongbo HeBenign Coloproctological Diseases Center, West China Hospital of Sichuan University, Chengdu, Sichuan, China.
Rurong WangDepartment of Anesthesiology, and Laboratory of Anesthesia and Intensive Care Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, China.ORCID 0000-0002-9213-3104
Sichuan University · CNSan Diego State University · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundCaudal epidural block (CEB) provides reliable anesthesia for adults undergoing anorectal surgery. Despite the widely utilization, the minimum effective concentration for 90% patients (MEC90) of ropivacaine for CEB remains unknown.

objectiveTo estimate MEC of ropivacaine for CEB in anorectal surgery.

designA prospective dose-finding study using biased coin design up-and-down sequential method.

settingOperating room and postoperative recovery area of Chengdu Shangjin Nanfu Hospital, from October 2019 to January 2020. PATIENTS: 50 males and 51 females scheduled for anorectal surgery.

interventionsWe conducted two independent biased coin design up-and down trials by genders. The concentration of ropivacaine administered to the first patient of male and female were 0.25% with fixed volume of 14ml for male and 12ml for female patients based on our previous study. In case of failure, the concentration was increased by 0.05% in the next subject. Otherwise, the next subject was randomized to a concentration 0.05% less with a probability of 0.11, or the same concentration with a probability of 0.89. Success was defined as complete sensory blockade of perineal area 15 min after the block evidenced by the presence of a lax anal sphincter and pain-free surgery.

main outcome measuresThe MEC of ropivacaine to achieve a successful CEB in 90%(MEC90) of the patients.

resultsThe MEC90 of ropivacaine for CEB were estimated to be 0.35% (95% CI 0.29 to 0.4%) for male and 0.353% (95%CI 0.22 to 0.4%) for female. By extrapolation to MEC in 99% of subjects (MEC99) and pooled adjacent violators algorithm (PAVA) adjusted responses, it would be optimal to choose 0.4% ropivacaine with a volume of 14ml for male and 12ml for female.

conclusionsA concentration of 0.35% ropivacaine with a volume of 14ml provided a successful CEB in 90% of the male patients, while 0.353% ropivacaine with a volume of 12ml provided a successful CEB in 90% of the female patients. A concentration of 0.4% and a volume of 14ml for male and 12 ml for female would be successful in 99% of the patients.

trial registrationChictr.org.cn identifier: No. ChiCTR 1900024315.

Indexed as

AdultAlgorithmsAnal CanalAnesthesia, EpiduralAnesthetics, LocalDose-Response Relationship, DrugFemaleHumansMaleMicrobial Sensitivity TestsMiddle AgedOperating RoomsPostoperative PeriodProspective StudiesRectumRopivacaineAnesthetics, LocalRopivacaine

Identifiers

PMID34534232
PMCPMC8448308
OpenAlexW3201553630

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.