Reachout Orthopedics - Issue 2

Duloxetine is a selective SNRI that is prescribed for treatment of depression and anxiety disorders [27]. It is also efficacious in treating pain in diabetic neuropathy and fibromyalgia [6]. The mechanism of its analgesic action could be explained by a combined central and peripheral pain modulating role [28] through the effect of serotonin and norepinephrine on descending inhibitory pain pathways in the brain and spinal cord [29] and activation of some cerebral prefrontal areas [5]. Also it has a antinociceptive effect through Na +  channel blocks [30] with antihyperalgesic effects through the inhibition of the neuronal cell firing resulting from peripheral injury [31]. Therefore, duloxetine has a great role in management of neuropathic pain and reducing postoperative pain. In addition, it may improve the depression and anxiety that are common during the perioperative period [32]. In this randomized study, despite the fact that each of the two drugs separately could not produce analgesia during move- ment, their combination induced signifi- cant reduction in pain score at rest and on movement over the study time points and also improved patients satisfaction at 24 h postoperatively. Although, each of the drugs separately were able to prolong the duration of first rescue to analgesia and reduce post- operative morphine consumption, the com- bination also remained significantly effective when compared with them. Therefore, this may accelerate the rehabilitation and reduce postoperative morbidity [33]. The analgesic effect of antidepressants is typically seen after 7 to 14 days, therefore It’s commonly used for chronic pain [34]. However, some investigators use duloxetine immediately preoperatively for acute pain management [8, 10]. In our study, we demonstrated that two doses of (60 mg) duloxetine 1 h before surgery and after 24 h could reduce opioid consumption with no significant effect on early postoperative pain score. Our result was comparable to Ho et al . [8] who assessed the use of two doses of duloxetine on pain scores postoperatively following knee arthroplasty. Also, Castro Alves et al . [10] examined the same regimen in patients undergoing abdominal hysterectomies and recently, Bedin et al . [11] performed the same assessment after spine surgery. On our study, the first dose of duloxetine was given 1 h before surgery. Table 2: Pain scores (NRS) at rest in the four groups. Group Variable Group (P) ( n =30) Group (E) ( n =30) Group (D) ( n =30) Group (D/E) ( n =30) P value At 0 h 5 (4-5.25)  bd 4 (3-4)  acd 4 (3-5)  bd 3 (3-4)  abc 0.0001 At 2 h 4 (3-5)  bd 3 (3-4)  acd 4 (3-5)  bd 3 (3-3)  abc 0.0001 At 4 h 4 (3-5)  bd 3 (3-4)  acd 3 (3-4)  bd 2 (2-3)  abc 0.0001 At 6 h 3 (3-4)  bd 3 (2-4)  ad 2.5 (2-3)  d 2 (1-3)  abc 0.0001 At 12 h 3 (3-3)  bd 3 (2-3)  ad 3 (2-3)  d 2.5 (1-3)  abc 0.0001 At 24 h 3 (2-3) bcd 2(2-3)  ad 2.5 (2-3)  ad 2 (1-2)  abc 0.0001 At 48 h 3 (2-3)  bcd 2 (2-3)  ad 2 (2-3)  ad 2 (0.75-2)  abc 0.0001 Placebo group (P), Etoricoxib (E), Duloxetine (D), Duloxetine/Etoricoxib (D/E) Data are presented as median (interquartile range). Data were analyzed by Mann–Whitney U-test and Kruksal-Wallis test and P <0.05 is considered significant. a: when compared with P group b: when compared with E group c: when compared with D group d: when compared with D/E group Table 3: Pain scores (NRS) on movement in the four groups. Group Variable Group (P) ( n =30) Group (E) ( n =30) Group (D) ( n =30) Group (D/E) ( n =30) P value 0 h 5 (5-6.25)  d 5 (5-6)  d 5 (5-6)  d 5 (4.5.25)  abc 0.013 After 2 h 5 (5-6)  d 5 (4-6)  d 5 (5-6)  d 5 (4-5)  abc 0.002 After 4 h 4 (4-5)  d 4 (4-5)  d 4 (4-5)  d 4 (3-4)  abc 0.019 After 6 h 4 (3-5)  d 4 (3-5)  d 4 (4-5)  d 4 (3-4)  abc 0.007 After 12 h 4 (3-5)  d 4 (3-4)  d 4 (3-4.25)  d 3 (3-4)  abc 0.030 After 24 h 4 (3-5)  d 4 (3-4.25)  d 4 (3-4)  d 3 (2.75-4)  abc 0.059 After 48 h 3.5 (3-4) d 3 (3-4)  d 3.5 (3-4)  d 3 (2.75-4)  abc 0.049 Placebo group (P), Etoricoxib (E), Duloxetine (D), Duloxetine/Etoricoxib (D/E) Data are presented as median (interquartile range). Data were analyzed by Mann–Whitney U-test and Kruksal-Wallis test and P <0.05 is considered significant. a: when compared with P group b: when compared with E group c: when compared with D group d: when compared with D/E group Table 4: Patient’s satisfaction in the four groups at 24 h. Group Patient satisfaction Group (P) ( n =30) Group (E) ( n =30) Group (D) ( n =30) Group (D/E) ( n =30) p Excellent 9 (30%) 12 (40%) 11 (36.7%) 21 (63.3%)* 0.004 Good 9 (30%) 10 (33.3%) 9 (30%) 5 (23.3%) 0.237 Fair 8 (26.7%) 5 (16.5%) 6 (20%) 2 (6.7%) 0.069 Poor 4 (13.3%) 3 (10%) 3 (10%) 2 (6.7%) 0.933 Data are presented as number (%). Data were analyzed using Chi square. Placebo group (P), Etoricoxib (E), Duloxetine (D), Duloxetine/Etoricoxib (D/E). P <0.05 is considered significant * P =0.016 when compare with P Table 5: Side effects in the four groups. Group Side effect Group (P) ( n =30) Group (E) ( n =30) Group (D) ( n =30) Group (D/E) ( n =30) p PONV (%) IIII&IV 13 (43.3%)* 7 (23.3%) 7 (23.3%) 5 (16.6%) 0.027 Somnolence 1 (3.3%) 1 (3.3%) 2 (6.7%) 3 (10%) 0.225 Pruritus 5 (16.7%) 4 (13.3%) 3 (10%) 3 (10%) 0.390 Dizziness 1 (3.3%) 2 (6.7%) 4 (13.3%) 3 (10%) 0.239 Headache 6 (20%) 3 (10%) 5 (16.7%) 4 (13.3%) 0.907 Data are presented as number (%). Data were analyzed using Chi square test and Fisher’s exact test. Placebo group (P), etoricoxib (E), duloxetine (D), duloxetine/etoricoxib (D/E). P <0.05 is considered significant. * P =0.024 when compare P and D/E 16 reachOut Orthopedics