Intravenous acetaminophen: a review of pharmacoeconomic science for perioperative use

Intravenous versus oral acetaminophen for pain and quality of recovery after ambulatory spine surgery: a randomized controlled trial

INTRODUCTION

As ambulatory spine surgery increases, efficient recovery and discharge become essential. Multimodal analgesia is superior to opioids alone. Acetaminophen is a central component of multimodal protocols and both intravenous and oral forms are used. While some advantages for intravenous acetaminophen have been touted, prospective studies with patient-centered outcomes are lacking in ambulatory spine surgery. A substantial cost difference exists. We hypothesized that intravenous acetaminophen would be associated with fewer opioids and better recovery.

METHODS

Patients undergoing ambulatory spine surgery were randomized to preoperative oral placebo and intraoperative intravenous acetaminophen or preoperative oral acetaminophen. All patients received general anesthesia and multimodal analgesia. The primary outcome was 24-hour opioid use in intravenous morphine milligram equivalents (MMEs), beginning with arrival to the postanesthesia care unit (PACU). Secondary outcomes included pain, Quality of Recovery (QoR)-15 scores, postoperative nausea and vomiting, recovery time, and correlations between pain catastrophizing, QoR-15, and pain.

RESULTS

A total of 82 patients were included in final analyses. Demographics were similar between groups. For the primary outcome, the median 24-hour MMEs did not differ between groups (12.6 (4.0, 27.1) vs 12.0 (4.0, 29.5) mg, p=0.893). Postoperative pain ratings, PACU MMEs, QoR-15 scores, and recovery time showed no differences. Spearman's correlation showed a moderate negative correlation between postoperative opioid use and QoR-15.

CONCLUSION

Intravenous acetaminophen was not superior to the oral form in ambulatory spine surgery patients. This does not support routine use of the more expensive intravenous form to improve recovery and accelerate discharge.

TRIAL REGISTRATION NUMBER

NCT04574778.

The efficacy of pentazocine + diclofenac versus paracetamol + diclofenac for post- caesarean section analgesia

Background

The most common major obstetric procedure is caesarean section (CS) and one of the greatest concerns for women after CS is to have optimal pain relief.

Aim

This study aims to compare the efficacy of pentazocine + diclofenac and paracetamol + diclofenac on post-operative analgesia after CS.

Methodology

This was a single-blind, randomised trial. Pregnant women that had CS were randomized into two groups. Group A received intramuscular pentazocine + rectal diclofenac postoperatively. Group B received intramuscular paracetamol + rectal diclofenac postoperatively. Post-operative pain was assessed by numeric rating scale at 1 h after the surgery, at 6 h, 12 h and 24 h. The result obtained was analysed using SPSS Version 22 and P < 0.05 was considered statistically significant.

Results

The median pain scores in both groups ranged from 2 to 3 across all periods of assessment. The pain relief was slightly better in the pentazocine + diclofenac group with no significant difference in the pain score between the two groups at all periods of assessment. The satisfaction level was good in 66.3% and 69.5% of the participants in the pentazocine + diclofenac and paracetamol + diclofenac group respectively but the difference was not statistically significant (χ² = 4.14, P = 0. 12). Nausea, vomiting and drowsiness were significantly more in the pentazocine + diclofenac combination (P < 0.001).

Conclusion

Both combination of analgesics provided adequate analgesia but pentazocine + diclofenac combination had better pain relief but was more associated with side effects.

Expert review and recommendations for the management of acute, chronic, and neuropathic pain in Qatar

BACKGROUND

Pain management is an evolving area of expertise in Qatar. Gaps in knowledge, inadequate training for physicians and nurses, and the absence of policies/guidelines are the main barriers to effective pain management in Qatar. In addition, the use of certain pain medication, especially opioids, is highly regulated, limiting their availability in outpatient pain management. These factors are responsible for the undertreatment of pain in Qatar. This study aimed to standardize evidence-based local recommendations for pharmacological treatment of pain in Qatar.

METHODS

An expert panel of physicians from different disciplines, with experience in diagnosis and treatment of the three pain types (i.e., acute, chronic, and neuropathic), was convened for two face-to-face meetings in Doha, Qatar, on November 29, 2019, and on February 22, 2020, with subsequent virtual meetings. A literature search was performed on Medline and Google Scholar databases from inception till December 2019, and all relevant articles were selected. Based on these articles and repeated feedback from the authors, the final pain treatment protocols were developed.

RESULTS

Recommendations for the treatment of acute pain, based on pain severity, followed three approaches: acetaminophen/paracetamol or non-steroidal anti-inflammatory drugs (NSAIDs) for mild pain and moderate pain and referral to a pain specialist for severe pain. Acetaminophen/paracetamol or NSAIDs is recommended for chronic pain, and the use of opioids was strongly discouraged because of its long-term side effects. For neuropathic pain, tricyclic antidepressants or gabapentin or pregabalin or serotonin-norepinephrine reuptake inhibitors were recommended first-line agents. Non-responders must be referred to neurologists or a pain specialist.

CONCLUSION

The expert panel provides recommendations for the management of acute, chronic, and neuropathic pain based on international guidelines adapted to local practice and treatment availability in Qatar. More importantly, the panel has recommended taking extreme caution in the use of opioids for long-term management of chronic pain and to refer the patient to a pain specialist clinician as required.

Variation in Intravenous Acetaminophen Use in Pediatric Hospitals: Priorities for Standardization

OBJECTIVES

The primary objective was to evaluate hospital variation in intravenous (IV) acetaminophen use across pediatric patient populations. The secondary objective was to identify populations with high use of IV acetaminophen and wide variation in practice to identify priority areas for cost reduction and practice standardization.

METHODS

We performed a retrospective study of children ≤18 years old hospitalized in 2019 in 48 US pediatric hospitals in the Pediatric Health Information System. Primary measures included IV acetaminophen use (percentage of encounters) and total days of therapy (DOT). A multivariable analysis identified clinical and demographic factors associated with IV acetaminophen use. High-priority groups for practice standardization were the All Patient Refined Diagnosis Related Groups in the top quartile of DOT, with wide variation of use across hospitals (interquartile range >50%).

RESULTS

Among 866 346 encounters, 14.4% received 1 dose of IV acetaminophen with 287 935 DOT, costing $29.8 million. In multivariable analysis age, payer, surgical procedure, ICU admission, total parenteral nutrition, and case mix index remained significantly associated with IV acetaminophen use. After multivariable adjustment, variation in hospital use ranged from <0.1% to 31% of all encounters. Twenty diagnosis groups accounted for 47% of total DOT (135 910 days) and 48% of cost ($14.2 million). Appendectomy, tonsil and adenoidectomy, and craniotomy were identified as top candidates for standardization efforts.

CONCLUSIONS

We observed large variation in IV acetaminophen use across pediatric hospitals and within diagnosis groups. These diagnoses represent candidates for practice standardization.

A systematic review and trial sequential analysis of intravenous vs. oral peri-operative paracetamol

Postoperative pain might be different after intravenous vs. oral paracetamol. We systematically reviewed randomised controlled trials in patients >15 years that compared intravenous with oral paracetamol for postoperative pain. We identified 14 trials with 1695 participants. There was inconclusive evidence for an effect of route of paracetamol administration on postoperative pain at 0–2 h (734 participants), 2–6 h (766 participants), 6–24 h (1115 participants) and >24 h (248 participants), with differences in standardised mean (95%CI) pain scores for intravenous vs. oral of −0.17 (−0.45 to 0.10), −0.09 (−0.24 to 0.06), 0.06 (−0.12 to 0.23) and 0.03 (−0.22 to 0.28), respectively. Trial sequential analyses suggested that a total of 3948 participants would be needed to demonstrate a meaningful difference in pain or its absence at 0–2 h. There were no differences in secondary outcomes. Intravenous paracetamol is more expensive than oral paracetamol. Substitution of oral paracetamol in half the patients given intravenous paracetamol in our hospital would save around £ 38,711 (€ 43,960 or US$ 47,498) per annum.

Intravenous Acetaminophen (Paracetamol) for Postcraniotomy Pain: Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Acute pain control after supratentorial craniotomy is considered among the most important indicators of postoperative recovery. The aim of this study was to determine the effects of intravenous acetaminophen on postcraniotomy pain.

METHODS

We searched databases including Embase, Scopus, Medline, Cochrane Library, and Web of Science until April 2019. Cochran Q test and I² statistic were used to assess the heterogeneity across included clinical trials. Standardized mean difference (SMD) and 95% confidence interval (CI) were used to estimate pooled effect sizes.

RESULTS

Out of 479 reports, 5 randomized controlled trials met the inclusion criteria and were appropriate for our meta-analysis, which included a total of 2635 patients. The pooled results of included clinical trials indicated that paracetamol intake significantly decreased rescue dose (SMD, -0.67; 95% CI, -1.15 to -0.19; P < 0.01; I² = 90.0%), total dosage of rescue (SMD, -0.78; 95% CI, -1.18 to -0.37; P < 0.01; I² = 86.0%), intensive care unit length of stay (SMD, -0.24; 95% CI, -0.44 to -0.04; P = 0.01; I² = 0.0%), and visual analog scale score (SMD, -0.16; 95% CI, -0.31 to -0.00; P = 0.04; I² = 71.7%) and increased patient satisfaction (SMD, 0.28; 95% CI, 0.14-0.43; P < 0.01; I² = 10.2%) among patients with craniotomy. Time to rescue (SMD, 0.21; 95% CI, -0.42 to 0.85; P = 0.51; I² = 94.3%) and hospital length of stay (SMD, -0.04; 95% CI, -0.24 to 0.16; P = 0.69; I² = 0.0%) did not significantly change after paracetamol intake.

CONCLUSIONS

The results of this systematic review and meta-analysis indicate that preoperative intravenous administration of acetaminophen is associated with decreased postoperative pain, need for rescue analgesics, and dosages of analgesics after craniotomy surgery.

FGF21 functions as a sensitive biomarker of APAP-treated patients and mice

Acetaminophen (APAP) is a common medication that induces hepatocellular damage in a time- or dose-dependent manner. Fibroblast growth factor 21 (FGF21) exerts a series of biological effects, including cellular repair. Compared to clinical diagnosis parameters, we aimed to evaluate whether FGF21 can serve as a sensitive biomarker for APAP-induced liver impairment. In the present study, we discussed comparable data from APAP-treated patients and parallelly established APAP-exposed mice for investigation. The resulting human serological data showed that APAP-treated patients have a visible reduction of FGF21 expression in undetected liver impairment of clinical diagnosis. In the animal study, APAP-exposed livers exhibited normal metabolic functions and liver functions, as revealed by biochemical test and histopathological examination. Endogenous FGF21 concentrations in APAP-treated mice were decreased in sera and liver cells. Moreover, comparable immunoassay data showed that hepatocellular FGF21 expression was reduced in a time-dependent manner. Taken together, these findings elucidate the involvement of abnormal FGF21 expression in early APAP-induced liver impairment. Interestingly, FGF21 may be a promising biomarker of APAP-exposed livers.

Controlling postoperative use of i.v. acetaminophen at an academic medical center

PURPOSE

Results of an interprofessional formulary initiative to decrease postoperative prescribing of i.v. acetaminophen are reported.

SUMMARY

After a medical center added i.v. acetaminophen to its formulary, increased prescribing of the i.v. formulation and a 3-fold price increase resulted in monthly spending of more than $40,000, prompting an organizationwide effort to curtail that cost while maintaining effective pain management. The surgery, anesthesia, and pharmacy departments applied the Institute for Healthcare Improvement's Model for Improvement to implement (1) pharmacist-led enforcement of prescribing restrictions, (2) retrospective evaluation of i.v. acetaminophen's impact on rates of opioid-related adverse effects, (3) restriction of prescribing of the drug to 1 postoperative dose on select patient care services, and (4) guideline-driven pain management according to an enhanced recovery after surgery (ERAS) protocol. Monitored metrics included the monthly i.v. acetaminophen prescribing rate, the proportion of i.v. acetaminophen orders requiring pharmacist intervention to enforce prescribing restrictions, and prescribing rates for select adjunctive analgesics. Within a year of project implementation, the mean monthly i.v. acetaminophen prescribing rate decreased by 83% from baseline to about 6 doses per 100 patient-days, with a decline in the monthly drug cost to about $4,000. Documented pharmacist interventions increased 2.7-fold, and use of oral acetaminophen, ketorolac, and gabapentin in ERAS areas increased by 18% overall.

CONCLUSION

An interprofessional initiative at a large medical center reduced postoperative use of i.v. acetaminophen by more than 80% and yielded over $400,000 in annual cost savings.

Pharmacokinetic Study of Intravenous Acetaminophen Administered to Critically Ill Multiple-Trauma Patients at the Usual Dosage and a New Proposal for Administration

The pharmacokinetic profile of intravenous acetaminophen administered to critically ill multiple-trauma patients was studied after 4 consecutive doses of 1 g every 6 hours. Eleven blood samples were taken (predose and 15, 30, 45, 60, 90, 120, 180, 240, 300, and 360 minutes postdose), and urine was collected (during 6-hour intervals between doses) to determine serum and urine acetaminophen concentrations. These were used to calculate the following pharmacokinetic parameters: maximum and minimum concentrations, terminal half-life, area under serum concentration-time curve from 0 to 6 hours, mean residence time, volume of distribution, and serum and renal clearance of acetaminophen. Daily doses of acetaminophen required to obtain steady-state minimum (bolus dosing) and average plasma concentrations (continuous infusion) of 10 μg/mL were calculated (10 μg/mL is the presumed lower limit of the analgesic range). Data are expressed as median [interquartile range]. Twenty-two patients were studied, mostly young (age 44 [34-64] years) males (68%), not obese (weight 78 [70-84] kg). Acetaminophen concentrations and pharmacokinetic parameters were these: maximum concentration 33.6 [25.7-38.7] μg/mL and minimum concentration 0.5 [0.2-2.3] μg/mL, all values below 10 μg/mL and 8 below the detection limit; half-life 1.2 [1.0-1.9] hours; area under the curve for 6 hours 34.7 [29.7-52.7] μg·h/mL; mean residence time 1.8 [1.3-2.6] hours; steady-state volume of distribution 50.8 [42.5-66.5] L; and serum and renal clearance 28.8 [18.9-33.7] L/h and 15 [11-19] mL/min, respectively. Theoretically, daily doses for a steady-state minimum concentration of 10 μg/mL would be 12.2 [7.8-16.4] g/day (166 [112-202] mg/[kg·day]); for an average steady-state concentration of 10 μg/mL, they would be 6.9 [4.5-8.1] g/day (91 [59-111] mg/[kg·day]). In conclusion, administration of acetaminophen at the recommended dosage of 1 g per 6 hours to critically ill multiple-trauma patients yields serum concentrations below 10 μg/mL due to increased elimination. To reach the 10 μg/mL target, and from a strictly pharmacokinetic point of view, continuous infusion may be more feasible than bolus dosing. Such a change in dosing strategy requires appropriate, pharmacokinetic-pharmacodynamic and specific safety study.

Estimating the Effect of Intravenous Acetaminophen for Postoperative Pain Management on Length of Stay and Inpatient Hospital Costs

Introduction

The provision of safe, effective, cost-efficient perioperative inpatient acute pain management is an important concern among clinicians and administrators within healthcare institutions. Overreliance on opioid monotherapy in this setting continues to present health risks for patients and increase healthcare costs resulting from preventable adverse events. The goal of this study was to model length of stay (LOS), potential opioid-related complications, and costs for patients reducing opioid use and adding intravenous acetaminophen (IV APAP) for management of postoperative pain.

Methods

Data for this study were de-identified inpatient encounters from The Advisory Board Company across 297 hospitals from 2012–2014, containing 2,238,433 encounters (IV APAP used in 12.1%). Encounters for adults ≥18 years of age admitted for cardiovascular, colorectal, general, obstetrics and gynecology, orthopedics, or spine surgery were included. The effects of reducing opioids and adding IV APAP were estimated using hierarchical statistical models. Costs were estimated by multiplying modeled reductions in LOS or complication rates by observed average volumes for medium-sized facilities, and by average cost per day or per complication (LOS: US$2383/day; complications: derived from observed charges).

Results

Across all surgery types, LOS showed an average reduction of 18.5% (10.7–32.0%) for the modeled scenario of reducing opioids by one level (high to medium, medium to low, or low to none) and adding IV APAP, with an associated total LOS-related cost savings of $4.5 M. Modeled opioid-related complication rates showed similar improvements, averaging a reduction of 28.7% (5.4–44.0%) with associated cost savings of $0.2 M. In aggregate, costs decreased by an estimated $4.7 M for a medium-sized hospital. The study design demonstrates associations only and cannot establish causal relationships. The cost impact of LOS is modeled based on observed data.

Conclusions

This investigation indicates that reducing opioid use and including IV APAP for postoperative pain management has the potential to decrease LOS, opioid-related complication rates, and costs from a hospital perspective.

Funding

Mallinckrodt Pharmaceuticals.

Patient satisfaction with intravenous acetaminophen: a pooled analysis of five randomized, placebo-controlled studies in the acute postoperative setting

Intravenous (IV) acetaminophen has been shown to reduce postoperative pain and opioid consumption, which may lead to increased patient satisfaction. To determine the effect IV acetaminophen has on patient satisfaction, a pooled analysis from methodologically homogenous studies was conducted. We obtained patient-level data from five randomized, placebo-controlled studies in adults undergoing elective surgery in which patient satisfaction was measured using a 4-point categorical rating scale. The primary endpoint was "excellent" satisfaction and the secondary endpoint was "good" or "excellent" satisfaction at 24 hr after first study drug administration. Bivariate analyses were conducted using the chi-square test and Student's t-test and multivariable analyses were conducted using logistic regression analysis. Patients receiving IV acetaminophen were more than twice as likely as those who received placebo to report "excellent" patient satisfaction ratings (32.3% vs. 15.9%, respectively). Of all variables that remained statistically significant in the multivariable analysis (i.e., type of surgery, duration of anesthesia, last pain rating, and opioid consumption), IV acetaminophen had the strongest positive effect on "excellent" patient satisfaction with an odds ratio of 2.76 (95% CI 1.81-4.23). Results for "excellent" or "good" satisfaction were similar. When given as part of a perioperative analgesic regimen, IV acetaminophen was associated with significantly improved patient satisfaction.

Evaluation of Intravenous Acetaminophen on Length of Stay in Abdominal Surgery Patients

Purpose

The objective of this study is to evaluate the effect of intravenous acetaminophen on length of stay (LOS) in abdominal surgery patients.

Methods

This retrospective, cohort chart review evaluated patients who underwent colon resection or pancreaticoduodenectomy between January 1, 2010 and August 31, 2013. The primary outcome is postoperative LOS. Secondary outcomes include opioid use, pain scores, and naloxone or laxative use. Patients who received intravenous acetaminophen were compared to patients who did not.

Results

A total of 329 patients were included, with 269 in the non-acetaminophen group compared to 60 patients in the acetaminophen group. There was no difference in postoperative LOS (9.2 s vs 9.1 days; P = .90). Postoperative LOS was also similar when controlling for surgery type. The acetaminophen group had reduced opioid consumption in the first 24 hours postoperatively (P = .02). However, pain scores were higher in the acetaminophen group, both in the first 24 hours (P = .007) and throughout the hospital stay (P < .001). Other clinical outcomes were similar between groups.

Conclusion

Intravenous acetaminophen was not associated with a decreased postoperative LOS at our institution.

Preemptive, preventive, multimodal analgesia: what do they really mean?

SUMMARY

To improve postoperative pain management, several concepts have been developed, including preemptive analgesia, preventive analgesia, and multimodal analgesia. This article will discuss the role of these concepts in improving perioperative pain management. Preemptive analgesia refers to the administration of an analgesic treatment before the surgical insult or tissue injury. Several randomized clinical trials have, however, provided equivocal evidence regarding the benefits of preincisional compared with postincisional analgesic administration. Current general consensus, therefore, indicates that use of preemptive analgesia does not translate into consistent clinical benefits after surgery. Preventive analgesia is a wider concept where the timing of analgesic administration in relation to the surgical incision is not critical. The aim of preventive analgesia is to minimize sensitization induced by noxious stimuli arising throughout the perioperative period. Multimodal analgesia consists of the administration of 2 or more drugs that act by different mechanisms for providing analgesia. These drugs may be administered via the same route or by different routes. Thus, the aim of multimodal analgesia is to improve pain relief while reducing opioid requirements and opioid-related adverse effects. Analgesic modalities currently available for postoperative pain control include opioids, local anesthetic techniques [local anesthetic infiltration, peripheral nerve blocks, and neuraxial blocks (epidural and paravertebral)], acetaminophen, nonsteroidal anti-inflammatory drugs, and cyclooxygenase-2-specific inhibitors as well as analgesic adjuncts such as steroids, ketamine, α-2 agonists, and anticonvulsants.

Impact of intraoperative acetaminophen administration on postoperative opioid consumption in patients undergoing hip or knee replacement

BACKGROUND

Opioid utilization for acute pain has been associated with numerous adverse events, potentially resulting in longer inpatient stays and increased costs.

OBJECTIVE

To examine the effect of intravenous (IV) acetaminophen administered intraoperatively on postoperative opioid consumption in adult subjects who underwent hip or knee replacement.

METHODS

This retrospective cohort study evaluated postoperative opioid consumption in 176 randomly selected adult subjects who underwent hip or knee replacement at Duke University Hospital (DUH). Eighty-eight subjects received a single, intraoperative, 1 g dose of IV acetaminophen. The other subjects did not receive any IV acetaminophen. This study evaluated mean opioid consumption (in oral morphine equivalents) during the 24-hour postoperative period in the 2 groups. Other endpoints included length of stay in the postanesthesia care unit (PACU), incidence of oversedation, need for acute opioid reversal, and adjunctive analgesic utilization.

RESULTS

Subjects who were given a single dose of intraoperative acetaminophen received an average of 149.3 mg of oral morphine equivalents during the 24 hours following surgery compared to 147.2 mg in participants who were not exposed to IV acetaminophen (P = .904). The difference in average length of PACU stay between the IV acetaminophen group (163 minutes) and those subjects not exposed to IV acetaminophen (169 minutes) was not statistically significant (P = .588). No subjects in the study experienced oversedation or required acute opioid reversal.

CONCLUSION

There was not a statistically significant difference in postoperative opioid consumption between patients receiving and not receiving IV acetaminophen intraoperatively.

Intravenous non-opioid analgesia for peri- and postoperative pain management: a scientific review of intravenous acetaminophen and ibuprofen

Pain is a predictable consequence following operations, but the management of postoperative pain is another challenge for anesthesiologists and inappropriately controlled pain may lead to unwanted outcomes in the postoperative period. Opioids are indeed still at the mainstream of postoperative pain control, but solely using only opioids for postoperative pain management may be connected with risks of complications and adverse effects. As a consequence, the concept of multimodal analgesia has been proposed and is recommended whenever possible. Acetaminophen is one of the most commonly used analgesic and antipyretic drug for its good tolerance and high safety profiles. The introduction of intravenous form of acetaminophen has led to a wider flexibility of its use during peri- and postoperative periods, allowing the early initiation of multimodal analgesia. Many studies have revealed the efficacy, safety and opioid sparing effects of intravenous acetaminophen. Intravenous ibuprofen has also shown to be well tolerated and demonstrated to have significant opioid sparing effects during the postoperative period. However, the number of randomized controlled trials confirming the efficacy and safety is small and should be used in caution in certain group of patients. Intravenous acetaminophen and ibuprofen are important options for multimodal postoperative analgesia, improving pain and patient satisfaction.

Scheduled intravenous acetaminophen reduces postoperative narcotic analgesic demand and requirement after laparoscopic Roux-en-Y gastric bypass

BACKGROUND

Intravenous (i.v.) acetaminophen has the potential to reduce postoperative narcotic analgesic requirement but this has not been reported in bariatric surgery. As lower dosages could reduce undesirable narcotic side effects, we investigated the opioid-sparing effect of concomitant i.v. acetaminophen in bariatric surgery.

METHODS

We performed a retrospective review of our electronic medical records of laparoscopic Roux-en-Y gastric bypasses (LRYGB) performed for severe obesity between 2011 and 2013. We identified 183 patients that received scheduled i.v. acetaminophen in addition to morphine sulfate (MSO4) patient-controlled analgesia (PCA). A cohort of 229 patients from the preceding 2 years who were treated with MSO4 PCA but not acetaminophen was used as a historical control. Patient demographic characteristics and narcotic use data were extracted from electronic medical records. Student's t test or linear regression was used as appropriate (P< .05).

RESULTS

During the first 24-hour postoperative period after LRYGB, narcotic analgesic demand (total PCA demand including nondelivery of narcotic due to lock-out) was reduced by 25% with the concomitant use of i.v. acetaminophen (40.5 versus 30.9 average pushes; P<.05). During the same period, narcotic analgesic dosage requirement was cut down by 20% in the study group (average of 29.9 versus 24.1 mg of MSO4; P<.05). Linear regression analysis confirmed that these changes were independent of age, gender, and body mass index distribution, or type 2 diabetes mellitus.

CONCLUSION

Scheduled i.v. acetaminophen reduces the demand for and the requirement of narcotic analgesia after LRYGB. We provide new evidence in support of the routine use of multimodal analgesia that includes scheduled i.v. acetaminophen in the initial 24-hour period after bariatric surgery.

The effect of intravenous infusion of paracetamol before anesthesia induction on the core and peripheral temperature changes and post-operative shivering in patients undergoing general anesthesia

Background:

Post-operative shivering is an unpleasant complication that various drugs are used to prevent and treat. It is tried to advice a suitable drug with the least side-effects. This study was carried out to examine the effect of intravenous Apotel on the post-operative shivering and core and peripheral body temperature.

Materials and Methods:

This clinical trial conducted in Al Zahra and Kashani Hospitals in Isfahan in 2012 on 64 patients undergoing upper limbs surgery with general anesthesia, which divided in two equal groups. In the first group, before induction, 15 mg/kg and up to 1 g paracetamol was infused in 100 cc normal saline within 20 min and control group was infused 100 cc normal saline during 20 min. Post-operative shivering and pain were recorded in the same time in addition to the core and peripheral temperature. The results were analyzed by SPSS ve.20 software.

Results:

In patients receiving Apotel, the core and peripheral temperature were significantly lower (P < 0.05). At 10 min after entering in recovery, 10 patients in the control group and 2 in the intervention group suffered from shivering (31.2% vs. 6.2%), which was significantly different (P = 0.02). Nineteen patients (29.7%) suffered from shivering in recovery (14 patients in the control group and 5 patients in the intervention group (43.8% vs. 15.6%)). In Apotel receiving group, the incidence of shivering in recovery was significantly lower (P = 0.014).

Conclusion:

Given the beneficial effects of Apotel in post-operative shivering and pain reduction, using the drug as a pre-drug is recommended in patients undergoing surgery with general anesthesia.

Management of Pain in the Emergency Department

Since pain is a primary impetus for patient presentation to the Emergency Department (ED), its treatment should be a priority for acute care providers. Historically, the ED has been marked by shortcomings in both the evaluation and amelioration of pain. Over the past decade, improvements in the science of pain assessment and management have combined to facilitate care improvements in the ED. The purpose of this review is to address selected topics within the realm of ED pain management. Commencing with general principles and definitions, the review continues with an assessment of areas of controversy and advancing knowledge in acute pain care. Some barriers to optimal pain care are discussed, and potential mechanisms to overcome these barriers are offered. While the review is not intended as a resource for specific pain conditions or drug information, selected agents and approaches are mentioned with respect to evolving evidence and areas for future research.