Postoperatives Schmerzmanagement

Boosting open-label placebo effects in acute induced pain in healthy adults (BOLPAP-study): study protocol of a randomized controlled trial

Introduction

Pain is a highly prevalent symptom in the hospital setting, but treatment options remain limited. Harnessing the placebo effect in an ethical manner could provide a new possibility to reduce pain in clinical practice. So called open-label placebos (OLP) have been shown to elicit significant effects in reducing acute pain. But, before implementation, more knowledge concerning the properties of OLPs is needed. This study aims to assess the duration of analgesic effects from OLP and to determine the possibility of boosting such effects.

Methods and analysis

This is the protocol of an ongoing (first patient enrolled in March 2023) single-site randomized trial investigating OLPs in two parts (i.e., substudies). In both parts, pain will be induced in healthy adults using an intradermal electrical stimulation model. Participants in Part 1 will have two study visits: An interventional visit with one OLP injection accompanied by an evidence-based treatment rationale and a control visit with no treatment. For Part 2, participants will be randomized into three groups: (1) A fixed-time "Booster" group including one single repetition of the OLP injection at a fixed time point, (2) an on-demand "Booster" group including one single repetition of the OLP injection on-demand, and (3) a control group who will receive just one OLP injection. Differences in pain ratings over time (using the Numeric Rating Scale) will be analyzed with several two-sample t-tests. The time point for a fixed-time "Booster" in Part 2 will be derived from Part 1 with additional statistical tools such as a broken-stick mixed-effect model.

Discussion

This study aims to further characterize the analgesic effects of OLPs. In doing so, it will provide valuable information needed for later implementation of OLPs in clinical practice, where they could play a role in multimodal analgesic concepts.

Ethics and dissemination

The "Ethikkommission Nordwest- und Zentralschweiz" (BASEC 2023-00296) approved the study protocol. Results of the analysis will be submitted for publication in a peer-reviewed journal.

Clinical Trial Registration

This study is registered at ClinicalTrials.gov (NCT05819476) and is listed in the Swiss National Registry at kofam.ch (SNCTP000005470).

Effects of benidipine, paracetamol, and their combination on postoperative and normal tissue pain thresholds

Introduction: In clinical practice, inadequate pain inhibition leads to increased morbidity and mortality. Increased intracellular calcium, oxidants, and proinflammatory cytokines are known to play a role in the pathogenesis of postoperative pain. Therefore, we investigated the analgesic effects of benidipine, paracetamol, and benidipine-paracetamol combination (BPC) on postoperative and normal pain thresholds in rats. Material and methods: Sixty-four male albino Wistar rats weighing 285-295 g were used. The without-incision rats were divided into 4 subgroups: healthy control, benidipine alone, paracetamol alone, and BPC. The scalpel-incision rats were divided into 4 subgroups: scalpel incision, scalpel incision + benidipine, scalpel incision + paracetamol, and scalpel incision + BPC. Paw pain thresholds of rats were measured using a Basile algesimeter. Biochemical analyses were performed on the paw tissues of 6 rats randomly taken from the experimental groups, each containing 8 rats. Rats were sacrificed immediately after the measurements. After the pain threshold tests were finished, the paw tissues were removed and malondialdehyde (MDA), total glutathione (tGSH), cyclooxygenase (COX), and interleukin-6 (IL-6) levels were measured. Results: There was no significant difference between the groups in paw pain threshold and measured biochemical parameters in rats without incision. The decrease in the pain threshold of the incised paw was also best prevented by BPC, followed by benidipine and then paracetamol. Furthermore, increases in scalpel-incised paw tissue MDA, COX-2, and IL-6 levels and the decrease in tGSH were significantly suppressed by benidipine and BPC, while paracetamol could only significantly inhibit the increase in IL-6 production. Conclusion: The combination of the L-type Ca2+ channel blocker benidipine and paracetamol (BPC) may provide potent analgesia. Our experimental results support that BPC may be useful in the treatment of severe pain that cannot be adequately inhibited by paracetamol.

Electro-Acupuncture Decreases Postoperative Pain and Improves Recovery in Patients Undergoing a Supratentorial Craniotomy

We performed this study to examine the effect of electro-acupuncture (EA) on postoperative pain, postoperative nausea and vomiting (PONV) and recovery in patients after a supratentorial tumor resection. Eighty-eight patients requiring a supratentorial tumor resection were anesthetized with sevoflurane and randomly allocated to a no treatment group (Group C) or an EA group (Group A). After anesthesia induction, the patients in Group A received EA at LI4 and SJ5, at BL63 and LR3 and at ST36 and GB40 on the same side as the craniotomy. The stimulation was continued until the end of the operation. Patient-controlled intravenous analgesia (PCIA) was used for the postoperative analgesia. The postoperative pain scores, PONV, the degree of dizziness and appetite were recorded. In the first 6 hours after the operation, the mean total bolus, the effective times of PCIA bolus administrations and the VAS scores were much lower in the EA group (p < 0.05). In the EA group, the incidence of PONV and degree of dizziness and feeling of fullness in the head within the first 24 hours after the operation was much lower than in the control group (p < 0.05). In the EA group, more patients had a better appetite than did the patients in group C (51.2% vs. 27.5%) (p < 0.05). The use of EA in neurosurgery patients improves the quality of postoperative analgesia, promotes appetite recovery and decreases some uncomfortable sensations, such as dizziness and feeling of fullness in the head.

[Interprofessional education in pain management: development strategies for an interprofessional core curriculum for health professionals in German-speaking countries]

The care of patients, suffering from acute, chronic, or malignant pain, requires systematic and interprofessional collaboration between all team members to ensure a holistic approach to pain management. In doing so, the different professions are often in a competitive, tense, or dependent relationship resulting from a lack of precise definitions and concepts regarding their responsibilities in the wide field of pain management. Considering pain management as a whole, we can define numerous interfaces concerning competencies and tasks which may open up some new perspectives on concepts of interprofessional education (IPE). Internationally, there have been many attempts to establish concepts of interprofessional education, and it is considered a great challenge to improve continuing medical education. However, interdisciplinary subjects like pain management may benefit from it. Apart from enhancing specialized knowledge, interprofessional education aims to consider the different roles, skills, and responsibilities as well as interprofessional strategies of decision-making. In Germany, only a few efforts have been made with regard to interprofessional pain education. In the following paper, different challenges, tasks, and roles within the field of pain management are discussed in the sense of potential areas of collaboration in the context of interprofessional education. Against this background, the Regensburg model for interprofessional pain management education is described as one national program to enhance the effectiveness of pain management.

[Implementation of standardized postoperative pain therapy for orthopaedic patients. Comparison between unsystematic and standardized pain therapy]

BACKGROUND

The painless clinic and postoperative pain therapy are currently major issues in the management of surgical procedures. The aim of this study was to evaluate the benefit of a standardized pain therapy on the postoperative pain level after orthopaedic procedures.

PATIENTS AND METHODS

We investigated two different groups of patients who underwent an orthopaedic surgical procedure. Group 1 (n = 249) received a pain therapy which was based on an individual and surgery-dependent concept whereas group 2 (n = 243) was treated with a standardized pain therapy concept. The effect of the treatment was monitored with a VAS-based protocol.

RESULTS

Up to day 9 after surgery there was a significant difference between the two groups in regard to the postoperative pain. The patients of group 2 had less pain but had more unwanted side effects caused by the pain therapy during the first 3 days after surgery. Mobility and mental disposition were positively affected.

CONCLUSION

The implementation of a standardized pain therapy is successful in reducing postoperative pain. Mobility and mental disposition are also influenced positively. As a consequence the incidence of unwanted side effects is rising.