Opioid-sparing effect of selective cyclooxygenase-2 inhibitors on surgical outcomes after open colorectal surgery within an enhanced recovery after surgery protocol

Table 1 Perioperative pain control regimen

Preoperative period	1 tablet of acetaminophen 500 mg
	± 1 tablet of a selective cyclooxygenase-2 inhibitor (either celecoxib 400 mg, etoricoxib 90 mg or etoricoxib 120 mg)
Intraoperative period	Balanced general anesthesia
	Application of atraumatic O-ring wound retractor (if available)
Postoperative period	Infiltration of 0.5% bupivacaine into fascial layer and muscle around the wound edge
	1 tablet of acetaminophen 500 mg every 6 h in the first 3 d
	± 1 tablet of a selective cyclooxygenase-2 inhibitor daily for 5-7 d
	Intravenous patient-controlled morphine (or tramadol) or intermittent intravenous morphine if pain score > 3

Table 2 Patient characteristics and operative details

	Patients with selective COX-2 inhibitor (n = 75)	Patients without selective COX-2 inhibitor (n = 75)	P-value
Age (yr)	64 (55-73)	65 (59-75)	0.15
Male	43 (57)	42 (56)	0.87
Weight (kg)	68 (51-58)	59 (50-66)	0.93
Body mass index	23.1 (20.9-25.4)	22.5 (20.6-24.6)	0.49
CR-POSSUM predicted mortality	1.8 (1.0-2.5)	1.9 (1.3-3.4)	0.07
Hematocrit (%)	38 (34-41)	35 (31-39)	0.0141
Serum albumin (g/L)	4.0 (3.6-4.3)	3.8 (3.4-4.1)	0.0131
Operative time (min)	180 (120-220)	160 (120-180)	0.21
Blood loss (mL)	150 (50-250)	150 (50-260)	0.75
Operation for malignancy	67 (89)	68 (91)	0.37
Rectal resection	41 (55)	37 (49)	0.51
Operation without bowel restoration	11 (15)	12 (16)	0.82
Use of atraumatic O-ring retractor	66 (88)	59 (79)	0.13
Adherence to ERAS protocol (%)	88 (82-88)	82 (82-88)	0.28

¹P < 0.05. COX-2: Cyclooxygenase-2; CR-POSSUM: The ColoRectal Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity; ERAS: Enhanced recovery after surgery.

Table 3 Postoperative pain score and intravenous opioid requirement

	Patients with selective COX-2 inhibitor (n = 75)	Patients without selective COX-2 inhibitor (n = 75)	P-value
Pain POD1	1.5 (0.7-2.1)	1.5 (0.5-2.7)	0.78
Pain POD2	0.7 (0-2.0)	0.6 (0-1.5)	0.74
Pain POD3	0.5 (0-1.5)	0.5 (0-1.7)	0.38
MME POD1	6 (2-12)	13 (6-20)	< 0.0011
MME POD2	3 (0-17)	20 (4-20)	< 0.0011
MME POD3	0 (0-0)	5 (0-15)	< 0.0011
MME/KG POD1	0.09 (0.03-0.23)	0.22 (0.11-0.42)	< 0.0011
MME/KG POD2	0.06 (0-0.28)	0.25 (0.07-0.37)	< 0.0011
MME/KG POD3	0 (0-0)	0.07 (0-0.25)	< 0.0011

¹P < 0.05. COX-2: Cyclooxygenase-2; MME: Morphine milligram equivalent; MME/KG: Morphine milligram equivalent per kilogram body weight; POD: Postoperative day.

Table 4 Gastrointestinal recovery, complication and hospital stay

	Patients with selective COX-2 inhibitor (n = 75)	Patients without selective COX-2 inhibitor (n = 75)	P-value
Time to tolerate solid diet (d)	1 (1-2)	2 (2-3)	< 0.0011
Time to defecate (d)	2 (2-3)	3 (3-4)	< 0.0011
Overall complication	9 (11)	17 (23)	0.08
Grade I	4	7
Grade II	5	7
Grade III	0	2
Grade IV	0	1
Prolonged postoperative ileus	4 (5)	6 (8)	0.75
Postoperative stay (d)
Median (IQR)	4 (3-5)	5 (4-6)	< 0.0011
Mean (SD)	4.3 (3.0)	5.3 (2.5)	0.0231
Readmission within 30 d	3 (4)	1 (1)	0.62

¹P < 0.05. If a patient had more than one complication, the highest Clavien-Dindo grade was reported. COX-2: Cyclooxygenase-2.