Multiorganizational consensus to define guiding principles for perioperative pain management in patients with chronic pain, preoperative opioid tolerance, or substance use disorder.

Significant knowledge gaps exist in the perioperative pain management of patients with a history of chronic pain, substance use disorder, and/or opioid tolerance as highlighted in the US Health and Human Services Pain Management Best Practices Inter-Agency Task Force 2019 report. The report emphasized the challenges of caring for these populations and the need for multidisciplinary care and a comprehensive approach. Such care requires stakeholder alignment across multiple specialties and care settings. With the intention of codifying this alignment into a reliable and efficient processes, a consortium of 15 professional healthcare societies was convened in a year-long modified Delphi consensus process and summit. This process produced seven guiding principles for the perioperative care of patients with chronic pain, substance use disorder, and/or preoperative opioid tolerance. These principles provide a framework and direction for future improvement in the optimization and care of 'complex' patients as they undergo surgical procedures.

Regional anesthesia for sickle cell disease vaso-occlusive crisis: A single-center case series.

Pain management is challenging for patients with sickle cell disease (SCD) who present in vaso-occlusive crisis (VOC). Opioid therapy is highly effective, nevertheless undesirable side effects can hinder their effectiveness. Regional anesthesia with deposition of perineural anesthetic offers nociceptive blockade, local vasodilatation, and reduces the inflammatory response. Among pediatric patients, continuous peripheral nerve block (CPNB) for perioperative adjunctive analgesia is safe. Herein, we describe the trajectory of a cohort of pediatric SCD patients with opioid-refractory upper-extremity VOC following placement of CPNBs for analgesia; highlighting reduced opioid consumption, improved pain scores, and decreased length of hospitalization.

A multisociety organizational consensus process to define guiding principles for acute perioperative pain management.

The US Health and Human Services Pain Management Best Practices Inter-Agency Task Force initiated a public-private partnership which led to the publication of its report in 2019. The report emphasized the need for individualized, multimodal, and multidisciplinary approaches to pain management that decrease the over-reliance on opioids, increase access to care, and promote widespread education on pain and substance use disorders. The Task Force specifically called on specialty organizations to work together to develop evidence-based guidelines. In response to this report's recommendations, a consortium of 14 professional healthcare societies committed to a 2-year project to advance pain management for the surgical patient and improve opioid safety. The modified Delphi process included two rounds of electronic voting and culminated in a live virtual event in February 2021, during which seven common guiding principles were established for acute perioperative pain management. These principles should help to inform local action and future development of clinical practice recommendations.

Deformation-dependent enzyme mechanokinetic cleavage of type I collagen.

Collagen is a key structural protein in the extracellular matrix of many tissues. It provides biological tissues with tensile mechanical strength and is enzymatically cleaved by a class of matrix metalloproteinases known as collagenases. Collagen enzymatic kinetics has been well characterized in solubilized, gel, and reconstituted forms. However, limited information exists on enzyme degradation of structurally intact collagen fibers and, more importantly, on the effect of mechanical deformation on collagen cleavage. We studied the degradation of native rat tail tendon fibers by collagenase after the fibers were mechanically elongated to strains of epsilon=1-10%. After the fibers were elongated and the stress was allowed to relax, the fiber was immersed in Clostridium histolyticum collagenase and the decrease in stress (sigma) was monitored as a means of calculating the rate of enzyme cleavage of the fiber. An enzyme mechanokinetic (EMK) relaxation function T(E)(epsilon) in s(-1) was calculated from the linear stress-time response during fiber cleavage, where T(E)(epsilon) corresponds to the zero order Michaelis-Menten enzyme-substrate kinetic response. The EMK relaxation function T(E)(epsilon) was found to decrease with applied strain at a rate of approximately 9% per percent strain, with complete inhibition of collagen cleavage predicted to occur at a strain of approximately 11%. However, comparison of the EMK response (T(E) versus epsilon) to collagen's stress-strain response (sigma versus epsilon) suggested the possibility of three different EMK responses: (1) constant T(E)(epsilon) within the toe region (epsilon<3%), (2) a rapid decrease ( approximately 50%) in the transition of the toe-to-heel region (epsilon congruent with3%) followed by (3) a constant value throughout the heel (epsilon=3-5%) and linear (epsilon=5-10%) regions. This observation suggests that the mechanism for the strain-dependent inhibition of enzyme cleavage of the collagen triple helix may be by a conformational change in the triple helix since the decrease in T(E)(epsilon) appeared concomitant with stretching of the collagen molecule.