Cost-effective multimodal analgesia in the perioperative period: Use of intravenous vs. oral acetaminophen

Perioperative Pain Management and Opioid Stewardship: A Practical Guide

“…Compared with the oral route, intravenous acetaminophen administration may offer faster onset and better analgesia thirty minutes after administration, but overall drug exposure after repeated doses and general clinical benefits are not significantly different [176,[386][387][388]. Additionally, the intravenous formulation may impose financial toxicity without additional benefit in patients with functional gastrointestinal tracts as discussed previously [389][390][391]. Selective COX-2 inhibitors or other NSAIDs should be incorporated into most postoperative pain regimens with consideration of the type of surgery, renal function, and cardiovascular risk factors (see Section 3.2).…”

Paracetamol: A Review of Guideline Recommendations

“…They provide faster T max and higher C max than tablets with the oral solution achieving higher bioavailability than intravenous formulation [ 31 ]. Intravenous paracetamol produces peak plasma concentrations in approximately 15 min compared to 45–50 min following oral administration, resulting, theoretically, in a faster onset of the analgesic effect (5 min) [ 31 , 32 ]. However, several studies, demonstrate similar analgesic efficacy of intravenous and oral preparations [ 31 , 32 , 33 , 34 , 35 , 36 ].…”

“…Intravenous paracetamol produces peak plasma concentrations in approximately 15 min compared to 45–50 min following oral administration, resulting, theoretically, in a faster onset of the analgesic effect (5 min) [ 31 , 32 ]. However, several studies, demonstrate similar analgesic efficacy of intravenous and oral preparations [ 31 , 32 , 33 , 34 , 35 , 36 ]. In a double-blind RCT, a heterogeneous group of 87 patients of the Emergency Department with moderate-to-severe pain (median age of 45 years, 60% females) were randomized to receive 1 g of paracetamol either intravenously or orally; the changes in Visual Analogue Score (VAS) for pain from baseline (67.9 ± 16.0 mm) to 30 min post-administration outcome did not differ between groups (−16.0 ± 19.1 mm in the intravenous group and −14.6 ± 26.4 in the oral group, p = 0.79) [ 33 ].…”

“…The authors concluded that intravenous and oral paracetamol produced a small but clinically significant decrease in pain [ 33 ]. In an RCT comparing intravenous and oral paracetamol in 120 patients undergoing hip and knee arthroplasty, 1 g of intravenous or oral paracetamol was administered preoperatively and then every 6 h for 24 h. The 24 h average pain VAS and 24 h hydromorphone rescue analgesia did not differ between the two groups, except for a lower pain VAS in the intravenous group at the postoperative 0–4 h interval [ 32 ]. In a double-blind RCT, 154 patients undergoing a total hip arthroplasty procedure received either intravenous or oral 1 g of paracetamol as part of a postoperative opioid-sparing, multimodal analgesia (i.e., 15–30 mg intravenous ketorolac every 8 h, for a total of 6 doses, and then oral meloxicam 7.5–15 mg until postoperative day three or discharge; upon request, tramadol 50–100 mg for mild–moderate pain or oxycodone 5 mg for severe pain; intravenous 2 mg hydromorphone as rescue analgesia for severe pain).…”

“…The authors concluded that patients in both groups had low pain scores and limited opioid usage [ 34 ]. Much alike, Johnson et al found that a single preoperative administration of 1 g of oral paracetamol produced postoperative analgesia similar to 1 g of intravenous paracetamol in patients undergoing laparoscopic cholecystectomy [ 32 ]. Fenlon et al studied 130 patients treated with oral or intravenous paracetamol and oral or intravenous placebo for third molar extraction; there was no difference in the analgesic outcome of satisfactory analgesia at 1 postoperative h [ 35 ].…”