Conditions: Postoperative Pain Intra-articular Injection Dexmedetomidine Magnesium Sulfate
Keywords: Analgesia Anesthesia Arthroscopy Bupivacaine Dexmedetomidine Injections, Intra-Articular Magnesium Pain, Postoperative
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 62
Healthy volunteers: no

Brief summary:
Arthroscopic meniscus surgeries are the most frequent orthopedic procedures. The objective of the study is to compare the effects of intraarticular local anesthetic and adjuvant (dexmedetomidine vs magnesium) combinations in postoperative pain and analgesic requirement. The investigators' hypothesis is adjuvants added to the local anesthetics decreases the total local anesthetic dose, provides more effective pain relief according to local anesthetic only, and decreases the postoperative systemic non-steroidal analgesic and opioid doses.

Detailed description:
Arthroscopic meniscus surgeries are the most frequent orthopedic procedures. However, irritation of free nerve endings in the synovial tissue and anterior fat pads and stretching and resection in the joint capsule lead to pain at various levels. Proper pain management enhances recovery, provides early mobilization and shortens length of hospital stay.

"Opioid-free" analgesia methods are frequently emphasized in published postoperative pain management guidelines and multimodal treatment approaches such as local anesthetic infiltration is recommended. In the treatment of knee pain, intra-articular drug injections are the most commonly used method because of minimal systemic side effects.

The drugs most commonly administered intraarticularly included local anesthetics (bupivacaine, levobupivacaine, lidocaine), opioids (morphine, fentanyl), magnesium sulfate, steroids, and α2 agonists (clonidine, dexmedetomidine).

Dexmedetomidine is a selective, specific, lipophilic and potent α2 adrenergic receptor agonist with sedative, anxiolytic, analgesic, antihypertensive and sympatholytic effects. It provides analgesic activity through both the central and peripheral nervous system. The analgesic effects of intra-articular administration of dexmedetomidine in arthroscopic surgeries have been demonstrated. Most side effects of this drug included hypotension and bradycardia. However, these side effects have never been encountered with intra-articular injection of the drug.

Magnesium is also an adjuvant drug which has a key role in nociceptive transmission, and acts as a NMDA (N-Methyl-D-Aspartate) antagonist in spinal neurons.

While opioid free anesthesia and analgesia methods gain importance nowadays, there has been increased interest in non-opioid analgesic drugs and multimodal analgesia applications. In order to increase the effects of local anesthetics and prolong their analgesic times, the addition of various adjuvants to local anesthetics is frequently used.

In the randomized controlled trials, intraarticular local anesthetic drugs combined with adjuvant drugs for postoperative analgesia were found to be superior to local anesthetic drugs alone. It is also known that local anesthetics have negative effects on chondrocytes. One of the goals of the investigators' in this study is to reduce the amount of local anesthetic used by adding adjuvant to local anesthetics.

In this study, the investigators plan to compare the efficacy of 2 adjuvants (magnesium sulfate and dexmedetomidine) combined with local anesthetics to be given intraarticularly for postoperative pain management after elective arthroscopic surgery.

Intraarticular high-volume drug injections may cause pain due to tension in the joint capsule. Additionally, the investigators aim to decrease the total drug volume with adjuvant drugs used in combination with local anesthetic, and thus to prevent joint capsule tension pain.

Arms:
arm 1: 5ml 0.25% Bupivacaine ve 50mcg Dexmetedomidin (diluted to 5ml with normal saline) intraarticularly at the end of surgery (total volume: 10 ml) arm 2: 5ml 0.25% Bupivacaine ve 5ml Magnesium Sulfate intraarticularly at the end of surgery (total volume: 10 ml)

Interventions: intervention 1: Precedex intervention 2: Magnesium Sulfate
Intervention descriptions: intervention 1: 10 ml of Bupivacaine ve 50mcg Dexmetedomidin mixture will be injected intraarticularly at the end of the surgery. intervention 2: 10 ml of Bupivacaine ve magnesium sulfate mixture will be injected intraarticularly at the end of the surgery.

Protocol document:
Prot_SAP_000.pdf: 
Comparison of Intra-articular Dexmedetomidine and Magnesium in Postoperative Pain 
Hande Gurbuz Aytuluk, MD1, Alper Gultekin, MD2, K. Tolga Saracoglu, Assoc Prof1 
 
1: University of Health Sciences, Kocaeli Derince Training and Research Hospital, Department 
of Anesthesiology and Reanimation, 41900 Derince, Kocaeli, Turkey 
2: University of Health Sciences, Kocaeli Derince Training and Research Hospital, Department 
of Orthopedics and Traumatology, University of Health Sciences, Kocaeli Derince Training 
and Research Hospital, 41900 Derince, Kocaeli, Turkey 
 
Trial registration: NCT03479216  
Date of the document:  
Initial Release: March 21, 2018  
Study Start (Actual): March 26, 2018 
Study Completion (Actual): August 1, 2018 
Last Update: October 12, 2018 
 
 
 
 
 


Objectives: Arthroscopic meniscus surgeries are the most frequent day-case orthopedic 
procedures. However, these surgeries can lead to pain at various levels. This study’s objective 
is to compare the efficacy of magnesium sulfate and dexmedetomidine in combination with 
local anesthetics to be given intraarticularly for postoperative pain management in patients 
undergoing arthroscopic meniscectomy under spinal anesthesia.  
 
Design and Subjects: Fifty-two patients aged between 18 and 65 years with American Society 
of Anesthesiologists physical status I or II who were scheduled for elective arthroscopic 
meniscectomy (right or left) under spinal anesthesia were included in this prospective, 
randomized, double-blind study.  
Methods: Patients were randomly assigned to group D (bupivacaine + dexmedetomidine) or 
group M (bupivacaine + magnesium sulphate). Following skin closure at the end of the 
procedure, 10 minutes before the tourniquet release, 10 mL of study solution was injected 
intraarticularly. Perioperative data, postoperative visual analogue scale (VAS) scores at the 2nd, 
4th, 6th, 8th, 12th, and 18th hours, and total analgesic consumption were recorded.  
 
Statistical Analysis: For continuous variables, the Kolmogorov-Smirnov test was used for the 
normality of data distribution and followed by the Mann-Whitney U test when a significant 
difference was found (p<0.05). For intergroup comparisons of categorical data, Pearson’s Chi-
square test or Fisher’s exact test was applied. Wilcoxon’s signed-ranks test was used for 
intragroup comparisons of VAS scores. All data are presented as means (SD), median (min 
max) or numbers as appropriate. P < 0.05 was considered to be statistically significant. 
 
 
 


Ethical Consideration: This study protocol was approved by the research ethics committee of 
Kocaeli University (Institutional Review Board, KIA 2018/92, Approval Date: February 20th, 
2018), written informed consent was obtained from all subjects participating in the trial and all 
procedures followed were in accordance with the ethical standards of the responsible committee 
on human experimentation and with the Helsinki Declaration of the World Medical 
Association.