Clinical trial NCT03499730: Does Midazolam Affect Postoperative Pain?
Official title: Does Preoperative Midazolam Dose Affect Postoperative Pain? - a Multicentric Observational Study in Open Inguinal Hernia Repair
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Pain, Postoperative
Keywords: Midazolam
Inguinal hernia
Lead sponsor: Universidade do Porto
Sponsor class: OTHER
First posted: 2018-04-17
Enrollment: 300
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Consecutive adult patients proposed for open inguinal hernia repair in Portuguese ambulatory surgery units, under general or spinal anesthesia.

Brief summary: To investigate whether midazolam has any effect on postoperative pain in outpatient surgery, the investigators will assess the impact of different midazolam doses on pain scores 24h, 7 days and 3 months after open inguinal hernia repair.

The investigators hypothesize that patients being administered higher midazolam doses will refer more pain.

Detailed description: Systemic midazolam prescribed perioperatively might have impact on pain, with studies suggesting antinociceptive and hyperalgesic effects. Anxiety might be a confounder in this association. In order to investigate the effect of midazolam on postoperative pain, a prospective cohort study will be conducted in four Portuguese ambulatory surgery units. A convenience sample with consecutive design will include patients admitted for open inguinal hernia repair. After anxiety and pain evaluation, a tailored dose of midazolam will be administered as premedication according to the anesthetist's best judgement within each unit's protocol (routine care; this dose may be null). Subsequent anesthesia and analgesia will be standardized. Postoperative pain will be blindly assessed by telephone interviews at 24h, 7 days, and 3 months. Statistical analysis will be performed separately for each gender, centre and type of anesthesia, adjusting for preoperative anxiety and other confounding variables with multivariate analysis.

The investigators intend to clarify the relation between anxiety, preoperative midazolam and postoperative pain.

Eligibility criteria: Inclusion Criteria:

- adults proposed for open inguinal hernia repair in Portuguese ambulatory surgery units

Exclusion Criteria:

* psychiatric disorders
* alcoholism
* illiteracy or poor understanding of the Portuguese language
* history of chronic pain under opioids
* recurrent surgery

Primary outcomes:
measure: Postoperative pain
timeFrame: 24h after surgery
Secondary outcomes:
measure: Postoperative pain
timeFrame: 7 days after surgery
measure: Postoperative pain
timeFrame: 3 months after surgery
measure: Patient satisfaction
timeFrame: 7 days after surgery
measure: Patient satisfaction
timeFrame: 3 months after surgery
measure: Analgesic consumption
timeFrame: 24h after surgery
measure: Analgesic consumption
timeFrame: 7 days after surgery
measure: Adverse events
timeFrame: 7 days after surgery
measure: Global surgery recovery index
timeFrame: 3 months after surgery
Other outcomes:
Locations:
city: Aveiro
country: Portugal
facility: Centro Hospitalar Baixo Vouga, EPE
city: Faro
country: Portugal
facility: Centro Hospitalar Universitário do Algarve
city: Santa Maria Da Feira
country: Portugal
facility: Centro Hospitalar Entre Douro e Vouga, EPE
city: Vila Nova De Gaia
country: Portugal
facility: Centro Hospitalar Vila Nova de Gaia / Espinho, EPE
Study officials:
affiliation: UPorto /CINTESIS
name: Caroline Dahlem, MD
role: PRINCIPAL_INVESTIGATOR
References:
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citation: Day MA, Rich MA, Thorn BE, Berbaum ML, Mangieri EA. A placebo-controlled trial of midazolam as an adjunct to morphine patient-controlled analgesia after spinal surgery. J Clin Anesth. 2014 Jun;26(4):300-8. doi: 10.1016/j.jclinane.2013.12.011. Epub 2014 Jun 2.
citation: Hasani A, Maloku H, Sallahu F, Gashi V, Ozgen SU. Preemptive analgesia with midazolam and diclofenac for hernia repair pain. Hernia. 2011 Jun;15(3):267-72. doi: 10.1007/s10029-010-0772-y. Epub 2010 Dec 28.
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