Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT03675555 |
Other study ID # |
R 47 / 2018 |
Secondary ID |
|
Status |
Completed |
Phase |
Phase 4
|
First received |
|
Last updated |
|
Start date |
March 1, 2018 |
Est. completion date |
August 31, 2018 |
Study information
Verified date |
December 2020 |
Source |
Ain Shams University |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
This study was conducted to evaluate the effect of a prophylactic dose of oral mirtazapine on
shivering compared with prophylactic intravenous infusion (IVI) dexamethasone in patients
undergoing gynecological surgeries under spinal anesthesia.
Description:
Enrollment After approval by the institute ethics committee, this study was conducted at
Ain-Shams university hospitals, from the 1st of March 2018 till the 31st of August 2018, on
300 patients aged 18-60 years of the American Society of Anesthesiologists (ASA) physical
status I or II and underwent gynecological surgeries under spinal anesthesia. A written
informed consent was obtained from all patients to participate in the study.
Patient's refusal, duration of surgery more than 120 min, obesity with body mass index (BMI)
>35 kg/m2, generalized infection or localized infection at level of blockade, neurologic
disease, coagulation disorder, patients with hypo- or hyperthyroidism, cardiopulmonary
disease, psychological disorders, a need for blood transfusion during surgery, an initial
body temperature >38.0C or <36.0C, a known history of alcohol or substance abuse, or
receiving vasodilators, or medications likely to alter thermoregulation excluded the patient
from the study.
Randomization and Blinding This study was designed to be a randomized, placebo-controlled,
double-blinded parallel study. Following enrollment, patients were randomized into 3 equal
groups;
1. The M (Mirtazapine) (Merta) group:(n=100) each patient received 30 mg Mirta tablet
orally with sips of water and 100 ml 0.9% sodium chloride (normal saline [NS]) (IVI)
over 15 min as a placebo for Dex 2 h preoperatively.
2. The D (Dexamethasone) (Dex) group: (n=100) each patient received a placebo tablet
identical to Mirta tablet orally with sips of water and Dex 8 mg ampoule diluted in 100
ml 0.9% NS IVI over 15 min, 2 h preoperatively.
3. The C (Control) group: (n=100) each patient received the same placebo tablet identical
to Mirta tablet orally with sips of water and 100 ml 0.9% NS IVI over 15 minas a placebo
for Dex 2 h preoperatively.
Randomization was done using computer-generated table of random numbers in a 1:1 ratio in
opaque and sealed envelope (SNOSE). The assigned treatment was written on a card and sealed
in opaque envelopes consecutively numbered. These envelopes were opened just immediately
before infusing the medication in the patient's room. The study drugs were prepared by the
hospital pharmacy and follow-up of patients were conducted by anesthesia residents not
involved in any other part of the study.
Study Protocol On arrival in the operating theatre, all patients had an inserted venous
cannula. I.V. fluids were preheated to 37oC. No other warming device was used. Lactated
Ringer's solution was warmed to 37 oC and was infused at 10 ml/kg over 30 min before spinal
anesthesia. The infusion rate was reduced to 6 ml/ kg.
Subarachnoid anesthesia was instituted at either L3/4 or L4/5 interspaces. Hyperbaric
bupivacaine, 5 mg /ml, 15 mg was injected using a 25 G Quincke spinal needle.
Supplemental oxygen (5 liter/ min) was delivered via a facemask during the operation. All
patients were covered with one layer of surgical drapes over the chest, thighs, and calves
during the operation and one cotton blanket over the entire body after operation. The
operating and recovery rooms temperatures were maintained at 23-25°C with approximately 60%
humidity.
Assessment parameters Heart rate, mean arterial pressure (MAP), and peripheral oxygen
saturation were recorded using standard noninvasive monitors before intrathecal injection and
thereafter at 5, 10, 15, 20 minutes then every 10 minutes to complete 90 minutes from the
intrathecal injection.
Sensory levels were assessed by pinprick to determine the peak sensory level and time to two
segment regression in minutes. Motor block were assessed by using Modified Bromage scale(16)
(0 = no block 1 = hip block, 2 = hip and knee block, 3 = hip, knee, and ankle block) to
determine the time to reach complete motor block and duration of motor blockade (minutes).
Sedation score was assessed with a four-point scale as per Filos et al.(17): 1: Awake and
alert. 2: Somnolent, but responsive to verbal stimuli. 3: Somnolent, arousable to physical
stimuli. 4: Unarousable.
Body temperature (axillary temperature) was recorded with an axillary thermometer. The
ambient temperature was measured by a wall thermometer. The ambient temperature will be
maintained at 25oC with constant humidity.
Shivering severity was assessed with a four-point scale (Badjatia et al):
1. None (Grade 0): no shivering noted on palpation of the masseter, neck, or chest wall
2. Mild (Grade 1): shivering localized to the neck and/or thorax only
3. Moderate (Grade 2): shivering involved gross movement of the upper extremities (in
addition to neck and thorax)
4. Severe (Grade 3): shivering involved gross movements of the trunk and upper and lower
extremities.
Shivering was assessed immediately before the block and every 10 minutes till the first 90
min (end point of the study) after the completion of the subarachnoid drug injection (start
point of the study). Grade 2 or 3 of shivering score was regarded failure of prophylaxis and
meperidine 25 mg IV was administered.
Side-effects, including hypotension (defined as a decrease in MAP of more than 20% from
baseline or a decrease of arterial blood pressure below 90 mmHg and baseline MAP was
calculated from three measurements taken on the ward before surgery) was treated by
crystalloid infusion and if necessary ephedrine 5 mg IV was administered. The amount of
ephedrine given in each group was recorded. Bradycardia was considered if the heart rate <50
beats/min and was treated with IV atropine (0.01mg/kg). Respiratory depression (RR < 12 bpm),
incidence of nausea and vomiting during early 2 hours postoperatively were recorded. IV
granisetron (1 mg) was given in case of vomiting or after 2 successive episodes of nausea.
Patients' satisfaction with shivering prophylaxis was done by asking the patient to answer
the question, "How would you rate your experience after the surgery?" using a 7-point Likert
verbal rating scale and acceptable satisfaction score of the patient being 5-7.
3-Analysis of Data:
The collected data were coded, tabulated, and statistically analyzed using IBM SPSS
statistics (Statistical Package for Social Sciences) software version 22.0, IBM Corp.,
Chicago, USA, 2013.