Chronic pain affects 20-25% of the global population, significantly impacts quality of life and socioeconomic productivity, placing a substantial burden on healthcare systems worldwide, particularly in lowand middle-income countries, and disproportionately affecting vulnerable populations, including older adults and cancer patients. Acetaminophen, a commonly used analgesic and crucial non-opioid alternative in chronic pain management, is frequently a first-line treatment for mild-to-moderate pain (including musculoskeletal pain, osteoarthritis, and headaches) and is often used with opioids for more severe pain. It modulates the central nervous system, primarily by inhibiting COX-2 enzymes to reduce prostaglandin production and pain signaling. In cancer-related pain and palliative care, it serves as an essential adjunct to more potent analgesics, reducing opioid consumption and side effects. As a key component of multimodal pain management, it enhances other medications' analgesic effects and minimizes their side effects. Future research should investigate acetaminophen's long-term effectiveness in more diverse populations (including the elderly and those with complex medication regimens), and its optimal role in multimodal analgesia and opioid-sparing strategies, particularly for cancer-related pain.

Background: The administration of intravenous (IV) acetaminophen during the perioperative period has been studied to evaluate its impact on postoperative pain management, opioid-sparing effects, rescue opioid analgesic use, and side effects [e.g., postoperative nausea and vomiting (PONV)]. However, the reports on the impact of the timing of IV acetaminophen administration during the perioperative period have yielded conflicting results. This review synthesizes findings from various studies to provide an understanding of the optimal timing and effectiveness of IV acetaminophen in different surgical settings. Methods: A literature review was conducted to evaluate studies related to IV acetaminophen administration, timing, dosing, and its effects on pain scores, opioid consumption, and common side effects (e.g., PONV). Specifically, the effect of the timing of IV acetaminophen administration (pre-, intrapostoperative, or perioperative) on clinical outcomes was studied. Results: Preemptive administration of IV acetaminophen before the surgical incision can significantly reduce opioid consumption and postoperative pain scores after abdominal and laparoscopic hysterectomy, cesarean surgeries, hip and knee arthroplasty, and endoscopic thyroidectomy. Intraoperative administration of IV acetaminophen during surgery has demonstrated reductions in opioid use and enhanced recovery metrics (e.g., earlier ability to discontinue PCA and advancement to solid food). Postoperative administration in the recovery room has been effective in reducing opioid consumption and improving pain scores, particularly in total knee arthroplasty. However, despite these benefits, some studies reported no significant differences in pain relief or opioid consumption. Comparisons with oral acetaminophen highlight its cost-benefit because even though it is more expensive, the IV formulation is faster-acting. IV administration shows advantages in specific settings like orthopedic surgeries (total knee and hip arthroplasty), major abdominal surgery, abdominal & laparoscopic hysterectomy, endoscopic thyroidectomy, cesarean deliveries, cardiac surgery, and spine fusion. IV acetaminophen achieves peak plasma concentrations rapidly, providing rapid analgesic effects with the recommended dose of 1g, and a maximum daily dose of 4g/day. Some studies suggest that an initial loading dose of 2 g may offer better analgesia. Conclusions: IV acetaminophen administration significantly influences its effectiveness in managing postoperative pain and reducing opioid use. Its most significant impact likely lies in reducing opioid requirements. Opioids carry a substantial risk of adverse events, especially in the postoperative setting. Reducing opioid dependence is a crucial public health goal. Clinicians should consider incorporating IV acetaminophen into multimodal analgesia regimens, emphasizing its benefits in pain control and opioid reduction.

Motion management has become an integral part of radiation therapy. Multiple approaches to motion management have been reported in the literature. To allow the sharing of experiences on current practice and emerging technology, the University of Sydney and the New South Wales/Australian Capital Territory branch of the Australasian College of Physical Scientists and Engineers in Medicine (ACPSEM) held a two-day motion management workshop. To inform the workshop program, participants were invited to complete a survey prior to the workshop on current use of motion management techniques and their opinion on the effectiveness of each approach. A post-workshop survey was also conducted, designed to capture changes in opinion as a result of workshop participation. The online workshop was the most well attended ever hosted by the ACPSEM, with over 300 participants and a response to the pre-workshop survey was received from at least 60% of the radiation therapy centres in Australia and New Zealand. Motion management is extensively used in the region with use of deep inspiration breath-hold (DIBH) reported by 98% of centres for left-sided breast treatments and 91% for at least some right-sided breast treatments. Surface guided radiation therapy (SGRT) was the most popular session at the workshop and survey results showed that the use of SGRT is likely to increase. The workshop provided an excellent opportunity for the exchange of knowledge and experience, with most survey respondents indicating that their participation would lead to improvements in the quality of delivery of treatments at their centres.

We aimed to appraise the methodological quality of existing guidelines for Enhanced Recovery After Surgery (ERAS) using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument and to identify the concordance of different recommendations.PubMed, Embase, Google Scholar, Web of Science, and clinical practice guideline websites were systematically searched. Four reviewers independently assessed the guidelines using the AGREE II instrument. The mean score of each AGREE II item, number of recommendations, strength of recommendation, and level of evidence were calculated. Agreement among reviewers was assessed using the intraclass correlation coefficient.We identified 23 guidelines from 7,127 records. The overall agreement among reviewers was considered good (intraclass correlation coefficient, 0.92; 95% confidence interval [CI], 0.86–0.96). The mean scores of the six AGREE domains were scope and purpose, 60.1% (95% CI, 55.9–64.1); stakeholder involvement, 40.7% (95% CI, 35.4–46.0); rigor of development, 44.7% (95% CI, 42.2–47.2); clarity and presentation, 69.8% (95% CI, 65.3–74.3); applicability, 37.2% (95% CI, 31.8–42.6); and editorial independence, 47.8% (95% CI, 39.0–56.7). Only 2/23 ERAS guidelines were considered applicable without modifications.The methodological quality of the ERAS management guidelines varied and was generally low. Future guideline development should adhere to the use of the AGREE II instrument and the GRADE system to better guide clinical practice and improve individualized treatment strategies.

Background: This review article discusses the pharmacodynamic effects of the most commonly used chronic medications by patients undergoing elective surgical procedures, namely cardiovascular drugs (e.g., beta blockers, alpha-2 agonist, calcium channel blockers, ACE inhibitors, diuretics, etc.), lipid-lowering drugs, gastrointestinal medications (H2-blockers, proton pump inhibitors), pulmonary medications (inhaled beta-agonists, anticholinergics,), antibiotics (tetracyclines, clindamycin and macrolide, linezolid.), opioids and non-opioids analgesics (NSAIDs, COX-2 inhibitors, acetaminophen), gabapentanoids, erectile dysfunction (ED) drugs, psychotropic drugs (tricyclic antidepressants [TCAs], monoamine oxidase inhibitors [MAOI], selective serotonin reuptake inhibitors [SSRIs], serotonin norepinephrine reuptake inhibitors [SNRIs], and cannabinol-containing drugs). In addition, the potential adverse drug-interactions between these chronic medications and commonly used anesthetic drugs during the perioperative period will be reviewed. Finally, recommendations regarding the management of chronic medications during the preoperative period will be provided. Materials and Methods: An online search was conducted from January 2000 through February 2021 with the Medline database through PubMed and Google Scholar using the following search terms/keywords: "chronic medications in the perioperative period", and "chronic medications and anesthetic implications." In addition, we searched for anesthetic side effects associated with the major drug groups. Results and Conclusions: An understanding of the pharmacodynamic effects of most used chronic medications is important to avoid untoward outcomes in the perioperative period. These drug interactions may result in altered efficacy and toxicity of the anesthetic medications administered during surgery. These drug-drug interactions can also affect the morbidity, mortality, recovery time of surgical patients and acute relapse of chronic illnesses which could lead to last minute cancellation of surgical procedures. Part II of this two-part review article focuses on the reported interactions between most commonly taken chronic medications by surgical patients and anesthetic and analgesic drugs, as well as recommendations regarding the handling these chronic medications during the perioperative period.

Background: This review article discusses the pharmacology of the most commonly used chronic medications in patients undergoing elective surgical procedures. The mechanism of action and adverse side effects of cardiovascular medications (e.g., beta blockers, alpha-2 agonist, calcium channel blockers, ACE inhibitors, diuretics), lipid-lowering drugs, gastrointestinal medications (H2-blockers, proton pump inhibitors), pulmonary medications (inhaled β-agonists, anticholinergics,), antibiotics (tetracyclines, clindamycin and macrolide, linezolid), opioids and non-opioids analgesics (NSAIDs, COX-2 inhibitors, acetaminophen), gabapentanoids, erectile dysfunction (ED) drugs, and psychotropic drugs (tricyclic antidepressants [TCAs], monoamine oxidase inhibitors [MAOI], selective serotonin reuptake inhibitors [SSRIs], serotonin norepinephrine reuptake inhibitors [SNRIs], and cannabinol-containing drugs) will be reviewed.Materials and Methods: An online search was conducted from January 2000 through February 2021 with the Medline database through PubMed and Google Scholar using the following search terms/keywords: "chronic medications in the perioperative period", and "chronic medications and anesthetic implications." In addition, we searched for anesthetic side effects associated with the major drug groups.Results and Conclusions: An understanding of the pharmacology and pharmacokinetics of most used chronic medications is important to avoid untoward outcomes in the perioperative period. These drug interactions may result in altered efficacy and toxicity of the anesthetic medications administered during surgery. These drug-drug interactions can also effect the morbidity, mortality, and recovery time of surgical patients. Part I of this two-part review article focuses on the mechanisms of action and adverse side effects of the chronic medications most commonly taken by surgical patients in the preoperative period.

Postoperative nausea and vomiting (PONV) and postdischarge nausea and vomiting (PDNV) remain common and distressing complications following surgery. The routine use of opioid analgesics for perioperative pain management is a major contributing factor to both PONV and PDNV after surgery. PONV and PDNV can delay discharge from the hospital or surgicenter, delay the return to normal activities of daily living after discharge home, and increase medical costs. The high incidence of PONV and PDNV has persisted despite the introduction of many new antiemetic drugs (and more aggressive use of antiemetic prophylaxis) over the last two decades as a result of growth in minimally invasive ambulatory surgery and the increased emphasis on earlier mobilization and discharge after both minor and major surgical procedures (e.g. enhanced recovery protocols). Pharmacologic management of PONV should be tailored to the patient’s risk level using the validated PONV and PDNV risk-scoring systems to encourage cost-effective practices and minimize the potential for adverse side effects due to drug interactions in the perioperative period. A combination of prophylactic antiemetic drugs with different mechanisms of action should be administered to patients with moderate to high risk of developing PONV. In addition to utilizing prophylactic antiemetic drugs, the management of perioperative pain using opioid-sparing multimodal analgesic techniques is critically important for achieving an enhanced recovery after surgery. In conclusion, the utilization of strategies to reduce the baseline risk of PONV (e.g. adequate hydration and the use of nonpharmacologic antiemetic and opioid-sparing analgesic techniques) and implementing multimodal antiemetic and analgesic regimens will reduce the likelihood of patients developing PONV and PDNV after surgery.

Elvir-Lazo, Ofelia L. MD; Yumul, Roya MD, PhD; White, Paul F. PhD, MD, FANZCA Author Information