Consensus Perioperative Management Best Practices for Patients on Transdermal Fentanyl Patches Undergoing Surgery.

PURPOSE OF REVIEW: The administration of a transdermal fentanyl patch can be complicated with different pharmacokinetics than other fentanyl preparations. RECENT FINDINGS: The medical condition and baseline opioid requirements must all be carefully considered when dosing a fentanyl patch. An advantage of the fentanyl patch is its ability to bypass the gastrointestinal tract and in many patients, provide effective analgesia with minimal side effects. Fentanyl patches must be carefully administered since morbidity and/or mortality can result from the following: Giving higher doses than a patient needs, combining the medication with potent sedatives, or heating a fentanyl patch. The use of a transdermal fentanyl patch for the treatment of acute postoperative pain is not recommended and any patient undergoing a surgical procedure should have the fentanyl patch removed preoperatively. The current manuscript discusses the history of fentanyl and the fentanyl patch, as well as perioperative considerations, contraindications, current clinical efficacy, and clinical adversities related to the transdermal fentanyl patch. Regarding the heating of a transdermal fentanyl patch, which significantly increases blood levels of fentanyl, it is of the utmost importance that the patch be removed prior to surgery.

Multimodal Analgesia, Current Concepts, and Acute Pain Considerations.

PURPOSE OF REVIEW: Management of acute pain following surgery using a multimodal approach is recommended by the American Society of Anesthesiologists whenever possible. In addition to opioids, drugs with differing mechanisms of actions target pain pathways resulting in additive and/or synergistic effects. Some of these agents include alpha 2 agonists, NMDA receptor antagonists, gabapentinoids, dexamethasone, NSAIDs, acetaminophen, and duloxetine. RECENT FINDINGS: Alpha 2 agonists have been shown to have opioid-sparing effects, but can cause hypotension and bradycardia and must be taken into consideration when administered. Acetaminophen is commonly used in a multimodal approach, with recent evidence lacking for the use of IV over oral formulations in patients able to take medications by mouth. Studies involving gabapentinoids have been mixed with some showing benefit; however, future large randomized controlled trials are needed. Ketamine is known to have powerful analgesic effects and, when combined with magnesium and other agents, may have a synergistic effect. Dexamethasone reduces postoperative nausea and vomiting and has been demonstrated to be an effective adjunct in multimodal analgesia. The serotonin-norepinephrine reuptake inhibitor, duloxetine, is a novel agent, but studies are limited and further evidence is needed. Overall, a multimodal analgesic approach should be used when treating postoperative pain, as it can potentially reduce side effects and provide the benefit of treating pain through different cellular pathways.

Tanezumab: a selective humanized mAb for chronic lower back pain.

Chronic lower back pain is a significant disease that affects nearly 20% of the worldwide population. Along with hindering patients' quality of life, chronic lower back pain is considered to be the second most common cause of disability among Americans. Treating chronic lower back pain is often a challenge for providers, especially in light of our current opioid epidemic. With this epidemic and an increased aging population, there is an imminent need for development of new pharmacologic therapeutic options, which are not only effective but also pose minimal adverse effects to the patient. With these considerations, a novel therapeutic agent called tanezumab has been developed and studied. Tanezumab is a humanized monoclonal immunoglobulin G2 antibody that works by inhibiting the binding of NGF to its receptors. NGF is involved in the function of sensory neurons and fibers involved in nociceptive transduction. It is commonly seen in excess in inflammatory joint conditions and in chronic pain patients. Nociceptors are dependent on NGF for growth and ongoing function. The inhibition of NGF binding to its receptors is a mechanism by which pain pathways can be interrupted. In this article, a number of recent randomized controlled trials are examined relating to the efficacy and safety of tanezumab in the treatment of chronic lower back pain. Although tanezumab was shown to be an effective pain modulator in major trials, several adverse effects were seen among different doses of the medication, one of which led to a clinical hold placed by the US Food and Drug Administration. In summary, tanezumab is a promising agent that warrants further investigation into its analgesic properties and safety profile.

New benzodiazepines for sedation.

There are currently new drugs being developed that have benzodiazepine properties. This review will examine remimazolam, 3-hydroxyphenazapam, adinazolam, clonazolam, and deschloroetizolam as well as other novel agents. All benzodiazepines are protein bound and only moderately lipid soluble. In addition to their baseline properties, they can be enzymatically broken down into active metabolites. The mechanism of action of these medications is related to polysynaptic pathway inhibition via direct interaction with GABA and modifiable chloride channels. The main neurological areas of involvement are primarily the amygdala and reticular activating system. Benzodiazepines are used for sedation and for adjuvants to general anesthetics and not as primary induction agents. We describe the characteristics of newer drugs being developed, including their pharmacologic profile, side effects and efficacy, as well as the most recent clinical trials and future directions in benzodiazepine development.

Adjunct medications for peripheral and neuraxial anesthesia.

Regional and neuraxial anesthesia can provide a safer perioperative experience, greater satisfaction, reduced opioid consumption, and reduction of pain, while minimizing side effects. Ultrasound technology has aided clinicians in depositing local anesthetic medication in precise proximity to targeted peripheral nerves. There are a plethora of adjuvants that have been utilized to prolong local anesthetic actions and enhance effects in peripheral nerve blocks. This manuscript describes the current state of the use of adjuncts, e.g., dexmedetomidine, dexamethasone, clonidine, epinephrine, etc., in regional anesthesia. Additionally, evidence behind dosing and block prolongation is summarized along with patient outcomes, adverse effects, and future directions.