During the past decade, numerous efforts were undertaken aiming at prolonging the analgesic effect of regional anesthesia. With the development of extended-release formulations and enhanced selectivity for nociceptive sensory neurons, a very promising contribution to the development of pain medications has been achieved. At present, liposomal bupivacaine is the most popular, non-opioid, controlled drug delivery system, but its duration of action, which is still controversially discussed, and its expensiveness have decreased initial enthusiasm. Continuous techniques can be seen as an elegant alternative for providing a prolonged duration of analgesia, but for logistic or anatomical reasons, they are not always the best choice. Therefore, focus has been directed towards the perineural and/or intravenous addition of old and established substances. As for perineural application, most of these so-called ‘adjuvants’ are used outside their indication, and their pharmacological efficacy is often not or only poorly understood. This review aims to summarize the recent developments for prolonging the duration of regional anesthesia. It will also discuss the potential harmful interactions and side effects of frequently used analgesic mixtures.

Background.: Transplantation activity during the first wave of the coronavirus disease 2019 (COVID-19) pandemic was severely affected worldwide. This retrospective analysis aimed to assess the impact of COVID-19 on organ donations and transplantations in the Eurotransplant region during the first 12 mo of the pandemic. Specifically, we compared donor and transplantation numbers during both waves to determine whether transplant systems adapted to this new reality. Methods.: All reported organ donations and transplantations from March 1, 2015, to February 28, 2021, were collected from the Eurotransplant International Foundation registry. The observation period from 2020 to 2021 was divided into three 4-mo periods, which were then compared with the corresponding periods of the preceding 5 y. COVID-19 cases for Eurotransplant countries were retrieved from the OurWorldInData.org database. Results.: Overall, the number of organ donors decreased by 18.3% (P < 0.0001) and the number of organ transplantations by 12.5% (P > 0.0001) compared with previous years. Pancreas transplantation was the most affected, followed by kidney, liver, heart, and lung transplant. In detail, during period 1, the number of organ donors decreased by 26.2% (P < 0.0001) and the number of organ transplantations by 16.5% (P < 0.0001), in period 2 by 5.5% (P < 0.0091) and 4.9% (P < 0.0001), and in period 3 by 23.1% (P < 0.0001) and 16.4% (P < 0.0001), respectively. Conclusions.: Organ donation and transplantation decreased drastically also during the second wave; however, despite the severity of the second wave, the decline was comparable with that of the first wave.

Mixtures of local anesthetics and adjuvants or mixtures of different local anesthetics are frequently used in regional anesthesia to accelerate the speed of onset and increase the effect and the length of action. Recent in vitro evidence revealed extensive crystallization in mixtures of local anesthetics or local anesthetic–adjuvant mixtures, including those previously deemed “safe”—like lidocaine plus sodium bicarbonate. Several guidelines recommend the use of local anesthetic–adjuvant or mixtures of local anesthetics. In this narrative review, the authors examine the chemical, pharmacologic, and clinical implications of local anesthetic mixture use, illustrate data on efficacy, and highlight critical limitations, including the risk of particle formation, lack of pharmacologic rationale, and unclear propensity for systemic toxicity. Moreover, the authors map out a practical risk versus benefit relationship with recommendations. In light of the unclear safety profile and equivocal clinical benefit of certain mixtures of local anesthetics and local anesthetic–adjuvant mixtures, the authors caution against the routine use of some mixtures at this point, especially for neuraxial techniques.