Does the Preoperative Midazolam Dose Affect Postoperative Pain?
- Conditions
- Pain, Postoperative
- Interventions
- Other: Normal salineProcedure: Spinal anesthesiaProcedure: SurgeryDrug: Postoperative analgesiaDrug: Rescue analgesiaDrug: Wound infiltrationDrug: Analgesia at home
- Registration Number
- NCT03534895
- Lead Sponsor
- Universidade do Porto
- 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 ambulatory surgery.
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 clinical trial will be conducted in Portuguese ambulatory surgery units. A convenience sample with consecutive design will include patients admitted for open inguinal hernia repair, varicose vein stripping, knee arthroscopy or hallux valgus surgery under spinal anesthesia. Patients will be randomized into 3 premedication groups, and this randomization will be stratified for each centre and each type of surgery. Postoperative pain will be blindly assessed by telephone interviews at 24h, 7 days, and 3 months.
The investigators will use multiple regression models to explore the interaction of midazolam dose with preoperative anxiety, gender and chronic benzodiazepine use, as they hypothesize there might be a differential effect of midazolam on postoperative pain amongst these subgroups.
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- All
- Target Recruitment
- 168
- adult patients submitted to open inguinal hernia repair, varicose vein stripping, knee arthroscopy or hallux valgus surgery in Portuguese ambulatory surgery units
- psychiatric disorders
- alcoholism
- illiteracy or poor understanding of Portuguese language
- history of chronic pain under opioids
- recurrent surgery
- contraindication for midazolam or deep sedation
- contraindication for spinal anesthesia
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description PC3 Midazolam Injectable Solution midazolam 0.06mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC3 Normal saline midazolam 0.06mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC3 Postoperative analgesia midazolam 0.06mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC3 Wound infiltration midazolam 0.06mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC1 Rescue analgesia 5mL normal saline intravenous, single-administration, as pre-medication PC1 Wound infiltration 5mL normal saline intravenous, single-administration, as pre-medication PC3 Rescue analgesia midazolam 0.06mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC2 Surgery midazolam 0.02mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC2 Wound infiltration midazolam 0.02mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC1 Normal saline 5mL normal saline intravenous, single-administration, as pre-medication PC1 Analgesia at home 5mL normal saline intravenous, single-administration, as pre-medication PC2 Midazolam Injectable Solution midazolam 0.02mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC1 Spinal anesthesia 5mL normal saline intravenous, single-administration, as pre-medication PC1 Surgery 5mL normal saline intravenous, single-administration, as pre-medication PC1 Postoperative analgesia 5mL normal saline intravenous, single-administration, as pre-medication PC2 Postoperative analgesia midazolam 0.02mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC2 Rescue analgesia midazolam 0.02mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC3 Spinal anesthesia midazolam 0.06mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC3 Surgery midazolam 0.06mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC2 Normal saline midazolam 0.02mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC2 Spinal anesthesia midazolam 0.02mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC2 Analgesia at home midazolam 0.02mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication PC3 Analgesia at home midazolam 0.06mg/Kg in 5mL normal saline, intravenous, single-administration, as pre-medication
- Primary Outcome Measures
Name Time Method Postoperative pain Day 1 after surgery Assessed by the Brief Pain Inventory severity score (24h recall time): mean of 4 items assessing pain at the moment of the interview, on average, at its least and at its worst during the last 24h
- Secondary Outcome Measures
Name Time Method Pain interference in daily life Month 3 after surgery Assessed by the Brief Pain Inventory interference score (24h recall time): interference of pain in general activity, mood, walking ability, normal work, relations with other people, sleep and enjoyment of life.
Analgesic consumption Day 7 after surgery Total analgesic drugs taken in a time period (first week after surgery)
Postoperative pain Month 3 after surgery Assessed by the Brief Pain Inventory severity score (24h recall time): mean of 4 items assessing pain at the moment of the interview, on average, at its least and at its worst during the last 24h. Features of neuropathic pain as assessed by DN4 patient-reported symptoms
Patient satisfaction Month 3 after surgery NRS 0-10
Adverse events Day 7 after surgery Number of patients with adverse events like bleeding, nausea, uncontrolled pain
Global surgery recovery index Month 3 after surgery Global surgery recovery index (0-100%)
Trial Locations
- Locations (2)
Centro Hospitalar Vila Nova de Gaia / Espinho, EPE
🇵🇹Vila Nova De Gaia, Portugal
Centro Hospitalar Entre Douro e Vouga, EPE
🇵🇹Santa Maria Da Feira, Portugal