Postoperative pain management: time to get back on track

Cannabinoid Analgesia in Postoperative Pain Management: From Molecular Mechanisms to Clinical Reality

Postoperative pain (POP) is a challenging clinical phenomenon that affects the majority of surgical patients and demands effective management to mitigate adverse outcomes such as persistent pain. The primary goal of POP management is to alleviate suffering and facilitate a seamless return to normal function for the patient. Despite compelling evidence of its drawbacks, opioid analgesia remains the basis of POP treatment. Novel therapeutic approaches rely on multimodal analgesia, integrating different pharmacological strategies to optimize efficacy while minimizing adverse effects. The recognition of the imperative role of the endocannabinoid system in pain regulation has prompted the investigation of cannabinoid compounds as a new therapeutic avenue. Cannabinoids may serve as adjuvants, enhancing the analgesic effects of other drugs and potentially replacing or at least reducing the dependence on other long-term analgesics in pain management. This narrative review succinctly summarizes pertinent information on the molecular mechanisms, clinical therapeutic benefits, and considerations associated with the plausible use of various cannabinoid compounds in treating POP. According to the available evidence, cannabinoid compounds modulate specific molecular mechanisms intimately involved in POP. However, only two of the eleven clinical trials that evaluated the efficacy of different cannabinoid interventions showed positive results.

Role of regional anesthesia and analgesia in enhanced recovery after colorectal surgery: a systematic review of randomized controlled trials

BACKGROUND

Effective analgesia is an important element of enhanced recovery after surgery (ERAS), but the clinical impact of regional anesthesia and analgesia for colorectal surgery remains unclear.

OBJECTIVE

We aimed to determine the impact of regional anesthesia following colorectal surgery in the setting of ERAS.

EVIDENCE REVIEW

We performed a systematic review of nine databases up to June 2020, seeking randomized controlled trials comparing regional anesthesia versus control in an ERAS pathway for colorectal surgery. We analyzed the studies with successful ERAS implementation, defined as ERAS protocols with a hospital length of stay of ≤5 days. Data were qualitatively synthesized. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool.

FINDINGS

Of the 29 studies reporting ERAS pathways, only 13 comprising 1170 patients were included, with modest methodological quality and poor reporting of adherence to ERAS pathways. Epidural analgesia had limited evidence of outcome benefits in open surgery, while spinal analgesia with intrathecal opioids may potentially be associated with improved outcomes with no impact on length of stay in laparoscopic surgery, though dosing must be further investigated. There was limited evidence for fascial plane blocks or other regional anesthetic techniques.

CONCLUSIONS

Although there was variable methodological quality and reporting of ERAS, we found little evidence demonstrating the clinical benefits of regional anesthetic techniques in the setting of successful ERAS implementation, and future studies must report adherence to ERAS in order for their interventions to be generalizable to modern clinical practice.

PROSPERO REGISTRATION NUMBER

CRD42020161200.

Multimodal spatio-temporal deep learning approach for neonatal postoperative pain assessment

The current practice for assessing neonatal postoperative pain relies on bedside caregivers. This practice is subjective, inconsistent, slow, and discontinuous. To develop a reliable medical interpretation, several automated approaches have been proposed to enhance the current practice. These approaches are unimodal and focus mainly on assessing neonatal procedural (acute) pain. As pain is a multimodal emotion that is often expressed through multiple modalities, the multimodal assessment of pain is necessary especially in case of postoperative (acute prolonged) pain. Additionally, spatio-temporal analysis is more stable over time and has been proven to be highly effective at minimizing misclassification errors. In this paper, we present a novel multimodal spatio-temporal approach that integrates visual and vocal signals and uses them for assessing neonatal postoperative pain. We conduct comprehensive experiments to investigate the effectiveness of the proposed approach. We compare the performance of the multimodal and unimodal postoperative pain assessment, and measure the impact of temporal information integration. The experimental results, on a real-world dataset, show that the proposed multimodal spatio-temporal approach achieves the highest AUC (0.87) and accuracy (79%), which are on average 6.67% and 6.33% higher than unimodal approaches. The results also show that the integration of temporal information markedly improves the performance as compared to the non-temporal approach as it captures changes in the pain dynamic. These results demonstrate that the proposed approach can be used as a viable alternative to manual assessment, which would tread a path toward fully automated pain monitoring in clinical settings, point-of-care testing, and homes.