Efficacy of Intravenous versus Oral Acetaminophen for Postoperative Pain Control Following Cesarean Delivery Stefanie Robinson MD, Sylvia H Wilson MD, Bethany Wolf PhD, Latha Hebbar MBBS Department of Anesthesia and Perioperative Medicine INTRODUCTION RESULTS Intravenous (IV) acetaminophen has established efficacy compared to placebo for several surgical procedures including total abdominal hysterectomy, tonsillectomy, and joint arthroplasty.1-2 Few studies have compared IV acetaminophen to active comparators including oral acetaminophen.1 Pain control in the parturient after a Cesarean delivery (CD) is of the utmost importance Multimodal approach for analgesia with scheduled oral acetaminophen has been found to be superior compared to as needed oral acetaminophen post-CD.3 Primary aim: Examine efficacy of scheduled IV versus oral acetaminophen post-CD. Demographic and intraoperative variable were similar among groups (Table 1). Cumulative opiate consumption differed among groups at 24 hours (P=0.017) but not 48 hours (P=0.389; Table 2). Median opiate consumption was reduced at 24 hours in the IV versus no acetaminophen group using pairwise comparisons and Bonferroni correction for multiple comparisons (P=0.015; Figure 1). Opiate consumption did not differ when comparing IV to oral acetaminophen and oral to no acetaminophen. IV acetaminophen (vs no acetaminophen) patients also were more likely to Not consume postoperative opiates (P=0.022) Report lower VAS with rest and ambulation (P=0.004; Figure 2) VAS pain scores at rest and side effects were similar among groups at 24 and 48 hours Table 1. Patient Characteristics Table 2. Cumulative Opiate Consumption   None Oral IV P DemographicsΨ Age (years) 31.2 (5.34) 30.5 (5.55) 28.7 (5.30) 0.078 Weight (kg) 94.5 (29.9) 90.2 (17.1) 89.4 (23.9) 0.561 Race (White) 23 (50.0) 31 (66.0) 27 (57.5) 0.296 Prior CD 36 (76.6) 32 (68.1) 40 (37.0) 0.15 Intraoperative* IV Opiates 9 (19.2) 4 (8.51) 8 (17.0) 0.309 Fentanyl 7 (14.9) 0.454 Morphine 6 (12.8) 3 (6.38) 5 (10.6) 0.684 Postoperative Time to First Opiate (Hours)Ψ 16.7 (14.3) 17.4 (14.1) 22.1 (10.9) 0.076 Time to Ambulate (Hours)Ψ 16.9 (7.01) 16.9 (5.72) 17.4 (8.57) 0.978 Side Effects* 17 (36.2) 23 (48.9) 18 (38.3) 0.403 Satisfaction† 95 (11, 100) 92.5 (45.5, 100) 95 (65, 100) 0.611   None Oral IV P 24 Hours 5mg (7) 0mg (6.75) 0mg (4.34) 0.017 48 Hours 17.5mg (17.5) 15mg (16.25) 15mg (13.75) 0.389 Data are presented as median (IQR) Opiates are presented as IV morphine equivalents. Fig 1. Opiate Consumption: Pairwise Comparisons 24 Hours 48 Hours P = 0.015 METHODS Prospective, single-blinded, randomized trial 141 parturients scheduled for elective CD Exclusions: Non-elective CD, contraindications to ketorolac, acetaminophen or spinal anesthesia with intrathecal opiates Three randomized groups IV acetaminophen: 1g every 8 hours for 24 hours Oral acetaminophen: 1g every 8 hours for 24 hours No acetaminophen Standardization: Spinal anesthesia for CD (bupivacaine 12mg, fentanyl 15µg, morphine 0.2mg) Scheduled ketorolac 30mg IV every 6 hours for 24 hours Oral and parenteral opiates prn. Outcomes Primary: Cumulative opiate consumption at 24 hours Secondary: (24 and 48 hours) VAS scores at rest and with ambulation (100mm scale) Patient satisfaction scores (100mm scale) Cumulative opiate consumption (at 48 hours) Statistics Continuous: ANOVA approach or Kruskal-Wallace test Categorical: Chi-square or Fisher’s exact test. Comparisons between groups in opiate consumption over time: generalized logistic-normal mixture model IV Morphine Equivalents (mg) Categorical variables are presented as n (%).* Continuous variables are presented as mean (SD)Ψ or median (range).† Side effects examined included nausea, vomiting and pruritus. SUMMARY Fig 2. Visual Analog Pain Scores (VAS) at Rest and with Ambulation (100mm Scale) IV acetaminophen decreased 24 hour opiate consumption compared to no acetaminophen IV acetaminophen did not decrease 24 hour opiate consumption compared to oral acetaminophen. IV acetaminophen was associated with decreased VAS scores with ambulation IV acetaminophen decreased the occurrence of consuming any opiates 24 Hours 48 Hours 24 Hours 48 Hours P < 0.004 Photos should be at least 300dpi, but not more than 5-12 mgs each. Your page is set to be enlarged 200% so do not change the page size to fit another poster size. Please call me and I will help you with a new page size if desired. Lisa 792-4724 Please note this is only a template for you to start with. You can change the font size, colors, column widths and the number of columns. VAS with Ambulation (mm) VAS at Rest (mm) REFERENCES Pain Pract. 2011;11:290-6. PMID: 21114616 Pain Med. 2011;12:961-81. PMID: 21627768 Int J Obstet Anesth. 2015;24:210-6. PMID: 25936786