Table 1 Summary of Characteristics of Included Studies

Sagir 2007

160 patients 18-65 yr

urological surgery

SA

C(40): saline iv

K(40):ketamine 0.5 mg/kg iv;G(40):granisetron 3 mg,iv;KG(40) ketamine 0.25/kg + granisetron 1.5 mg iv

All patients were covered with drapes and a cotton blanket. Fluids were preheated to 37^oc

Honarmand 2008

120 patients 18-60 yr

orthopaedic surgery

SA

C(30) saline iv; K(30) ketamine 0.5 mg/kg iv;

M(30) midazolam 75 μg/kg iv; KM(30) ketamine 0. 25 mg/kg + midazolam 37.5 μg/kg iv

Fluids were preheated to 37^oc

Zahra 2008

120 patients 5-12 yr

tonsillectomy surgery

GA

C(40):saline

K(40):ketamine 1 mg/kg;P(40):pethidine 0.5 mg/kg

None.

Han 2010

93 patients 51-78 yr

transurethral resection of the prostate

SA

C(31): epidural 0.75% ropivacaine

K1(32): epdural ketamine 0.2 mg/kg + 0.75%ropivacaine; K2(30): epidural ketamine 0.4 mg/kg + 0.75%ropivacaine

None

Shakya 2010

120 patients

Lower abdominal surgery

SA

C(40):saline iv

K(40): ketamine 0.25 mg/kg iv;O(40):ondansetron 4 mg iv

Patients were covered with standard single blanket

Ayatollahi 2011

120 patients 20-50 yr

endoscopic sinus surgery

GA

C(30): saline iv

K1(30): 0.3 mg/kg iv; K2(30): 0.5 mg/kg iv; M(30): meperidine 0.4 mg/kg iv

Patients were covered with a cotton blanket

Norouzi 2011

120 patients 18-65 yr

elective orthopedic surgery

GA

C(30):saline iv

K1(30):ketamine 0.125 mg/kg iv;K2(30):ketamine 0.25 mg/kg iv;K3(30):ketamine 0.5 mg/kg iv

None

Wason 2012

200 patients 18-65 yr

ower abdominal or lower limb surgery

SA

C(50):saline iv

K(50):ketamine 0.5 mg/kg iv;C(50):clonidine 75mcg;T(50):tramadol 0.5 mg/kg iv

Fluids were preheated to 37^oc

Zavareh 2012

135 patients 18–70 yr

elective surgery

GA

K(45):ketamine 0.5 mg/kg iv;

P(45):pethidine 0.5 mg/kg;D(45):dexamethasone,0.6 mg/kg

None

Abdelhalim 2014

120 patients 18-45 yr

ENT surgery

GA

C(30): saline iv

O(30): ondansetron 8 mg iv; K(30): ketamine 0.5 mg/kg iv; OK(30) ondansetron 8 mg + ketamine 0.25 mg/kg iv

None

Petskul 2016

183 patients 18-65 yr

orthopedic surgery

GA

C(92):saline iv

K(91):ketamine 0.25 mg/kg iv

All patients were warmed by air force warmer

Mohtadi 2016

117 patients 18-40 yr

cesarean section

SA

C(39):saline iv

K(39):ketamine 0.25 mg/kg,iv;O(39):ondansetron 4 mg,iv

None

Hasannasab 2016

120 patients 20-45 yr

gynecologic surgery

GA

K(40): ketamine 0.25 mg/kg iv;

M(40): meperidine 20 mg iv; D(40): doxapram 0.25 mg/kg iv

Patients were covered with a standard blanket

Lakhe 2017

120 patients 18–65 years

gynecological and orthopedic surgery

SA

C(30):saline,iv

T(30):tramadol 0.5 mg/kg iv O(30):ondansetron 4 mg,iv;K(30):ketamine 0.25 mg/kg iv

Patients were covered with drapes

Lema 2017

123 patients 18-39 yr

cesarean section

SA

C(41):saline iv

K(41):ketamine 0.2 mg/kg iv;T(41): tramadol 0.5 mg/kg iv

Patients were covered with drapes