Ketamine Versus Dexmedetomidine as an Adjuvant in Ultrasound-guided Supraclavicular Brachial Plexus Block
Phase: NA
Conditions: Supraclavicular Brachial Plexus Block
Sponsor: Minia University

Cover page 
Ketamine versus dexmedetomidine as an adjuvant in ultrasound-
guided supraclavicular brachial plexus block 
NCT number: 146:4/2019 
document date: February 21, 2019 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
Ketamine versus dexmedetomidine as an adjuvant in ultrasound-
guided supraclavicular brachial plexus block 
Background:  peripheral nerve block has gained increased popularity due to less 
postoperative pain, reduced need for post-operative analgesic drugs, reduction of PACU time, 
and improved patient satisfaction. 
 
Objectives: The aim of the study was to compare the effect of ketamine and dexmedetomidine 
as additives to bupivacaine on onset and duration of the block, post-operative VAS, and 
analgesic consumption, after ultrasound guided supraclavicular nerve block.  
Study Design 
Study type: interventional 
Actual enrollment: 75 patients 
Allocation: randomized 
Intervention model: parallel assignment 
Intervention model description: The patients were randomly classified 
into three groups using computer generated table numbers each contain 
(25) patient.  
Ketamine group (group K): 20 ml 0.5%bupivacaine and 20 ml 0.9% 
normal saline plus 1 mg\kg ketamine,   
Dexmedetomidine group (group D): 20 ml 0.5% bupivacaine and 20 ml 
0.9% normal saline plus 1µg\kg dexmedetomidine 
Control group (group C): 20 ml 0.5%bupivacaine and 20 ml 0.9% normal 
saline.   
Masking: double blind (participant and investigator) 
Masking description: The investigator’s study is a prospective, 
randomized, double blind 
 
Actual study start date: April 21, 2019 
Primary study completion date February. 21, 2020 
Site of study: El-Minia university hospital 
Eligibility criteria:  
Age: 18-75 years 
Sex: All 
ASA Physical Status: I–II 
Inclusion Criteria: The study included 75 patients undergoing elective 
and emergency forearm and hand surgeries under ultrasound guided 
supraclavicular brachial plexus block. 

Exclusion Criteria:   
Patient with bleeding disorders  
Damage or disease of the brachial plexus 
Uncontrolled diabetes mellitus 
Patients with neuromuscular diseases 
Patients with local skin infection at the site of injection  
Patients with known hypersensitivity to studied drugs 
Outcome Measure: 
Primary outcome:  
1. Evaluate onset and duration of sensory and motor block 
secondary outcome:  
1. Assess postoperative pain score 
2. time to first analgesic request 
3. total analgesic requirements  
4. sedation score secondarily 
 
Preparation of the studied medications:   The patients were randomly 
classified into three groups using computer generated table numbers each 
contain (25) patient. Ketamine group (group K): 20 ml 0.5%bupivacaine 
and 20 ml 0.9% normal saline plus  1 mg\kg ketamine,  Dexmedetomidine 
group (group D)  20 ml 0.5% bupivacaine and 20 ml 0.9% normal saline 
plus 1µg\kg dexmedetomidine (precedex® Hospira,Inc.,Lake Forest USA).  
Control group (group C) 20 ml 0.5%bupivacaine and 20 ml 0.9% normal 
saline.  All medications were prepared in similar sterile coated bottles by 
the supervisor who didn't included in anesthetic or operative team, 75 
bottles numbered from 1 to 75 were prepared . After completion of the 
study, the key was opened by the supervisor  
Block technique   : On patient's arrival to the operating room, a 20 G 
intravenous cannula was inserted  in a peripheral vein of unaffected limb 
and standard monitoring commenced as noninvasive blood pressure 
(NIBP), 
(ECG), 
and 
Oxygen 
saturation 
(Spo2) 
(UltraviewSL2700,Spacelaps,USA), all equipment and drugs for general 
anesthesia and resuscitation were prepared, the ultrasound device (Sonosite,  
Nanomax ,USA ) lubricating gel, 21guge 50 mm length, short bevel, insulated 
stimulating needle (Laboratoires pharmaceutiques, Vygon,France). Patient lie 
supine with head turned to the other side and ipsilateral arm adducted 
gently with flexed elbow. Under complete aseptic condition , the identified 

area and the ultrasound probe  was prepared with anti-septic (Povidone-
Iodine 10%) solution  and the skin infiltrated with 1-2 ml of  lidocaine 2% 
solution subcutaneously, the brachial plexus was visualized by placing the 
transducer in the sagittal plane in the supraclavicular fossa behind the 
middle-third of the clavicle. Two distinct appearances of the 
supraclavicular brachial plexus was seen, it either appeared as a grape like 
cluster of 5 to 6 hypoechoic circles, located lateral and superior to the 
subclavian artery between the anterior and middle scalene muscles at the 
lower cervical region or as 3 hypoechoic circles with hyperechoic outer 
rings , the predetermined volume of 40 mL of the study drug solution was 
administered around the brachial plexus after negative aspiration to avoid 
accidental intravascular injection, expansion  of the brachial plexus sheath 
was considered  as an indication of correct needle placement,  multiple 
injections  was used to deposit the total amount of the study drugs, skin 
massage for about 3 minutes was done to facilitate drug distribution . 
Parameters assessed : 
-Hemodynamic data: The hemodynamic variables as HR, MAP and Spo2 
were assessed. The parameters were recorded preoperatively just before 
the block as a baseline value, at 5,10,20,30,60, 90 minutes during the 
operative time and at 1,2,4,6,9 and 12 hours after the end of operation. 
-Sensory block was assessed by pin prick test using a 3-point scale [16]  
Grade 0 = normal sensation, Grade 1 = loss of sensation of pin prick 
(analgesia), and Grade 2 = loss of sensation of touch (anesthesia).  
- Motor block was determined by thumb abduction (radial nerve), thumb 
adduction (ulnar nerve), thumb opposition (median nerve), and flexion of 
elbow (musculocutaneous nerve) according to the modified Bromage  3 
point scale   :Grade 0: Normal motor function with full flexion and 
extension of elbow, wrist, and fingers. Grade 1: Decreased motor strength 
with ability to move the fingers only. Grade 2: Complete motor block with 
inability to move the fingers [16].  
- Onset time for sensory and motor block: the time interval between the end 
of local anesthetic administration and complete sensory and motor block 
by min. 
- Sensory block duration: the time interval between the complete sensory 
block and complete resolution of anesthesia on all the nerves (score 0 ( 

-Motor block duration: the time interval from complete motor block to 
complete recovery of motor function of hand and forearm (grade 0) by 
hours.  
-Visual analogue scale (VAS): postoperative, the patients were 
familiarized with a 10-point visual analog scale (VAS) ranged from 0 = no 
pain, up to 10 = the worse imaginable pain. VAS was measured at 1, 2, 3, 
6, 9, 12 hour. When it is equals or >4 we give IM diclofenac sodium (75 
mg amp) (voltaren , Novartis Pharmaceuticals Corporation, Switzerland). 
-Time of first analgesic request: The time passed from supraclavicular 
brachial plexus block to the patient's first request for analgesic medication 
by hours 
-Total analgesic requirements in 24 hours  ) diclofenac consumption)  
-Sedation score: was assessed according to the modified Ramsay Sedation 
Scale 1987(RSS) from 1-6 as follows: 1 = anxious, agitated, restless; 2 = 
cooperative, oriented, tranquil; 3 = responds to commands only; 4 = brisk 
response to light glabeller tap or loud noise; 5 = sluggish response to light 
glabellar tap or loud noise; 6 = no response [17].  
-Adverse effects: any adverse effects such as  hypotension (i.e. 20% 
decrease relative to baseline), bradycardia  (HR <60 beats/min), nausea, 
vomiting, hypoxemia (SpO2 <90%),local hematoma, hemothorax 
,pneumothorax ,recurrent laryngeal nerve block ,intravascular injection 
,Horner's syndrome and signs of local anesthetic toxicity were recorded 
during the operation and for 12 hours postoperative. 
Statistical analysis 
Results were calculated as mean ± standard deviation (SD) and Mann- 
Whitney  test for quantitative variables, categorical variables were 
calculated using Chi- square test or Fisher’s exact test Statistical 
significance was determined  when  P ≤ 0.05. All statistical analysis was 
done using SPSS software (version 13.0, SPSS Inc., Chicago, Illinois). To 
determine the sample size, we used sample size calculator for comparing 
two independent means [18]. It was calculated regarding the onset of 
analgesia using local anesthetics for supraclavicular nerve block, which 
was determined in previous studies [19]. Assuming a pooled standard 
deviation of 12 minutes and expected mean difference of 10 minutes 
between test and reference groups, the study would require a sample size 
of 23 patients for each group, with a power of 80% and two sided level of 
significance of 5%, at a confidence interval (CI) of 95%. Therefore, a 

sample of 25 patients in each group could be enough to achieve the targeted 
onset of analgesia.