Local infiltration of the surgical wound with levobupivacaine, ibuprofen, and epinephrine in postoperative pain: An experimental study

Grimace scale, burrowing, and nest building for the assessment of post-surgical pain in mice and rats-A systematic review

Several studies suggested an informative value of behavioral and grimace scale parameters for the detection of pain. However, the robustness and reliability of the parameters as well as the current extent of implementation are still largely unknown. In this study, we aimed to systematically analyze the current evidence-base of grimace scale, burrowing, and nest building for the assessment of post-surgical pain in mice and rats. The following platforms were searched for relevant articles: PubMed, Embase via Ovid, and Web of Science. Only full peer-reviewed studies that describe the grimace scale, burrowing, and/or nest building as pain parameters in the post-surgical phase in mice and/or rats were included. Information about the study design, animal characteristics, intervention characteristics, and outcome measures was extracted from identified publications. In total, 74 papers were included in this review. The majority of studies have been conducted in young adult C57BL/6J mice and Sprague Dawley and Wistar rats. While there is an apparent lack of information about young animals, some studies that analyzed the grimace scale in aged rats were identified. The majority of studies focused on laparotomy-associated pain. Only limited information is available about other types of surgical interventions. While an impact of surgery and an influence of analgesia were rather consistently reported in studies focusing on grimace scales, the number of studies that assessed respective effects was rather low for nest building and burrowing. Moreover, controversial findings were evident for the impact of analgesics on post-surgical nest building activity. Regarding analgesia, a monotherapeutic approach was identified in the vast majority of studies with non-steroidal anti-inflammatory (NSAID) drugs and opioids being most commonly used. In conclusion, most evidence exists for grimace scales, which were more frequently used to assess post-surgical pain in rodents than the other behavioral parameters. However, our findings also point to relevant knowledge gaps concerning the post-surgical application in different strains, age levels, and following different surgical procedures. Future efforts are also necessary to directly compare the sensitivity and robustness of different readout parameters applied for the assessment of nest building and burrowing activities.

Generation of cost-effective MXene@polydopamine-decorated chitosan nanofibrous wound dressing for promoting wound healing

Herein, we designed and fabricated a MXene@polydopamine (MXene@PDA)-decorated chitosan non-woven fabric (M-CNF) hemostatic dressing with super hydrophilic properties for wound repair and regeneration. The M-CNF exhibit excellently wettability characteristics which can rapidly absorb water from blood. Moreover, M-CNF with 15 mg/mL MXene@PDA (M-CNF-15) show better antibacterial performance, excellent blood-clotting performance, better blood cell and platelet adhesion ability than CNF, displaying both active and passive hemostatic mechanisms to accelerate blood clotting in mouse-liver injury model. In addition, the M-CNF-15 also shows better wound healed performance than Tegaderm™ film in a full-thickness skin defect model, and further demonstrating that the MXene@PDA can promote fibrinogen reformation the at the initial phases of the wound healing process. Therefore, this strategy for designing and manufacturing of multi-functional M-CNF wound dressing will have great potential for active local hemostasis and wound repair and regeneration.

The Effect of Subcutaneous and Intraperitoneal Instillation of Local Anesthetics on Postoperative Pain after Laparoscopic Varicocelectomy: A Randomized Controlled Trial

Background: The main goal of the present randomized clinical trial was to investigate the effects of subcutaneous administration of two different local anesthetics at trocar incision sites at the abdominal wall in combination with intraoperative intraperitoneal instillation of local anesthetics, on the character of postoperative pain, in adolescents who underwent laparoscopic varicocelectomy. Methods: A total of 60 patients with a median age of 16 years, who received laparoscopic varicocele repair, were included in this randomized clinical trial. The patients were randomly assigned to three study groups receiving 2% lidocaine, 0.5% levobupivacaine, or the control group. The Visual Analogue Scale (VAS) was used by a blinded nurse at four different time points (2, 6, 12 and 24 h after the surgery) to measure pain intensity. Results: The significant effect of time on the pain intensity (p = 0.001) was found. Additionally, the interaction between time and different local analgesics (p < 0.001) was observed. In patients in whom 0.5% levobupivacaine has been used, significantly lower VAS pain scores were recorded at each time point assessed, in comparison with the patients who received 2% lidocaine or the patients from the control group in whom no local anesthetic was applied (p < 0.001). Furthermore, in patients in whom 2% lidocaine was administrated, significantly lower pain levels according to VAS were reported than in those from the control group, except for the time point at 24 h after surgery when pain levels were comparable. Concerning the postoperative pain control, the number of patients who requested oral analgesics postoperatively was significantly lower in the group of patients in whom local anesthetic was administrated intraoperatively (2% lidocaine—n = 4, 20%; 0.5% levobupivacaine—n = 1, 5%) compared to the patients who did not receive any local anesthetic during the surgery (n = 13; 65%) (p < 0.001). Conclusion: A significant reduction in postoperative pain intensity and analgesics consumption in patients undergoing laparoscopic varicocelectomy who received intraoperative local anesthetic was observed. The best effect on postoperative pain intensity, according to the VAS score, was achieved by 0.5% levobupivacaine.

Paraffin-Coated Hydrophobic Hemostatic Zeolite Gauze for Rapid Coagulation with Minimal Adhesion

To solve the problem of strong adhesion and excessive blood loss caused by the use of hydrophilic zeolite gauze (Z-Gauze) in uncontrollable bleeding, we have modified the surface of commercial Z-Gauze with a paraffin coating and prepared a hydrophobic dressing PZ-Gauze. After paraffin coating, the adhesion of Z-Gauze was reduced without an obvious decrease in coagulation activity. The clotting time of the hydrophobic PZ-Gauze was reduced from 378.3 to 154.6 s compared with that of cotton gauze, and the peeling force was decreased from 348.8 to 84.7 mN compared with that of Z-Gauze. Besides, PZ-Gauze can efficiently cut down the blood loss during treatment. On the basis of in vitro and in vivo experiments, it is confirmed that surface hydrophobic modification does not change the procoagulant performance because of the maintained cation exchange capacity of zeolites, and the reduced blood loss as well as enhanced difficulty for fibrin adhesion is attributed to its hydrophobicity. This is different from the traditional gauze procoagulant theories, where gauze hydrophilicity and procoagulant performance are always positively correlated.

Chitin Nanocrystals as an Eco-friendly and Strong Anisotropic Adhesive

To solve the damage to the environment and human body caused by organic solvent adhesives in the utilization process, chitin nanocrystal (ChNC) suspension is explored as a strong anisotropic adhesive, which is an eco-friendly and water-based adhesive with high adhesive strength. ChNCs extracted from crab shells are rod-like nanoparticles with high aspect ratios, which are mainly employed as reinforcing polymer nanocomposites and biomedicine nanomaterials. ChNC suspension sandwiched between substrates forms a long-range ordered superstructure by a self-assembly process. ChNC nanoglue exhibits high anisotropy adhesion strength, i.e., an in-plane shear strength (5.26 MPa) and an out-of-plane shear strength (0.46 MPa) for glass substrates. Moreover, the ChNC nanoglue is suitable to many substrates, such as glass, plastic, wood, metal, paper, etc. The ChNC nanoglue shows high biocompatibility toward the fibroblast cell and rat skin, proving their excellent biosafety. As an eco-friendly and high-performance adhesive, ChNC nanoglue shows promising applications in daily life and industrial fields.

The development and use of facial grimace scales for pain measurement in animals

The measurement of pain in animals is surprisingly complex, and remains a critical issue in veterinary care and biomedical research. Based on the known utility of pain measurement via facial expression in verbal and especially non-verbal human populations, "grimace scales" were first developed a decade ago for use in rodents and now exist for 10 different mammalian species. This review details the background context, historical development, features (including duration), psychometric properties, modulatory factors, and impact of animal grimace scales for pain.

Comparison of perioperative analgesia using the infiltration of the surgical site with ropivacaine alone and in combination with meloxicam in cats undergoing ovariohysterectomy

Background

Infiltration of the surgical site with local anesthetics combined with nonsteroidal anti-inflammatory drugs may play an important role in improving perioperative pain control. This prospective, randomized, blinded, controlled clinical trial aimed to evaluate intraoperative isoflurane requirements, postoperative analgesia, and adverse events of infiltration of the surgical site with ropivacaine alone and combined with meloxicam in cats undergoing ovariohysterectomy. Forty-five cats premedicated with acepromazine/meperidine and anesthetized with propofol/isoflurane were randomly distributed into three treatments (n = 15 per group): physiological saline (group S), ropivacaine alone (1 mg/kg, group R) or combined with meloxicam (0.2 mg/kg, group RM) infiltrated at the surgical site (incision line, ovarian pedicles and uterus). End-tidal isoflurane concentration (FE’ISO), recorded at specific time points during surgery, was adjusted to inhibit autonomic responses to surgical stimulation. Pain was assessed using an Interactive Visual Analog Scale (IVAS), UNESP-Botucatu Multidimensional Composite Pain Scale (MCPS), and mechanical nociceptive thresholds (MNT) up to 24 h post-extubation. Rescue analgesia was provided with intramuscular morphine (0.1 mg/kg) when MCPS was ≥6.

Results

Area under the curve (AUC) of FE’ISO was significantly lower (P < 0.0001) in the RM (17.8 ± 3.1) compared to S (23.1 ± 2.2) and R groups (22.8 ± 1.1). Hypertension (systolic arterial pressure > 160 mmHg) coinciding with surgical manipulation was observed only in cats treated with S and R (4/15 cats, P = 0.08). The number of cats receiving rescue analgesia (4 cats in the S group and 1 cat in the R and RM groups) did not differ among groups (P = 0.17). The AUC of IVAS, MCPS and MNT did not differ among groups (P = 0.56, 0.64, and 0.18, respectively). Significantly lower IVAS pain scores were recorded at 1 h in the RM compared to the R and S groups (P = 0.021–0.018). There were no significant adverse effects during the study period.

Conclusions

Local infiltration with RM decreased intraoperative isoflurane requirements and resulted in some evidence of improved analgesia during the early postoperative period. Neither R nor RM infiltration appeared to result in long term analgesia in cats undergoing ovariohysterectomy.

Superhydrophobic hemostatic nanofiber composites for fast clotting and minimal adhesion

Hemostatic materials are of great importance in medicine. However, their successful implementation is still challenging as it depends on two, often counteracting, attributes; achieving blood coagulation rapidly, before significant blood loss, and enabling subsequent facile wound-dressing removal, without clot tears and secondary bleeding. Here we illustrate an approach for achieving hemostasis, rationally targeting both attributes, via a superhydrophobic surface with immobilized carbon nanofibers (CNFs). We find that CNFs promote quick fibrin growth and cause rapid clotting, and due to their superhydrophobic nature they severely limit blood wetting to prevent blood loss and drastically reduce bacteria attachment. Furthermore, minimal contact between the clot and the superhydrophobic CNF surface yields an unforced clot detachment after clot shrinkage. All these important attributes are verified in vitro and in vivo with rat experiments. Our work thereby demonstrates that this strategy for designing hemostatic patch materials has great potential.

Clinical Management of Pain in Rodents

The use of effective regimens for mitigating pain remain underutilized in research rodents despite the general acceptance of both the ethical imperative and regulatory requirements intended to maximize animal welfare. Factors contributing to this gap between the need for and the actual use of analgesia include lack of sufficient evidence-based data on effective regimens, under-dosing due to labor required to dose analgesics at appropriate intervals, concerns that the use of analgesics may impact study outcomes, and beliefs that rodents recover quickly from invasive procedures and as such do not need analgesics. Fundamentally, any discussion of clinical management of pain in rodents must recognize that nociceptive pathways and pain signaling mechanisms are highly conserved across mammalian species, and that central processing of pain is largely equivalent in rodents and other larger research species such as dogs, cats, or primates. Other obstacles to effective pain management in rodents have been the lack of objective, science-driven data on pain assessment, and the availability of appropriate pharmacological tools for pain mitigation. To address this deficit, we have reviewed and summarized the available publications on pain management in rats, mice and guinea pigs. Different drug classes and specific pharmacokinetic profiles, recommended dosages, and routes of administration are discussed, and updated recommendations are provided. Nonpharmacologic tools for increasing the comfort and wellbeing of research animals are also discussed. The potential adverse effects of analgesics are also reviewed. While gaps still exist in our understanding of clinical pain management in rodents, effective pharmacologic and nonpharmacologic strategies are available that can and should be used to provide analgesia while minimizing adverse effects. The key to effective clinical management of pain is thoughtful planning that incorporates study needs and veterinary guidance, knowledge of the pharmacokinetics and mechanisms of action of drugs being considered, careful attention to individual differences, and establishing an institutional culture that commits to pain management for all species as a central component of animal welfare.

Comparison of the Efficacy, Side Effects, and Cost of Modafinil and Intranasal Mometasone Furoate in Obstructive Sleep Apnea-Hypopnea Syndrome: A Preliminary Clinical Study

Background

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is characterized by repeated episodes of reduction in airflow due to the collapse of the upper airway during sleep. The aim of this study was to compare clinical outcome, side effects, and cost of treatment between modafinil and intranasal mometasone furoate in patients with OSAHS.

Material/Methods

Patients with OSAHS (N=250) were divided into two groups: the modafinil group (MG) (N=125) were treated with 100 mg modafinil twice a day; the intranasal mometasone furoate group (IMFG) (N=125) were treated with 100 μg of intranasal mometasone furoate in the evening. Quality of life, grading of OSAHS, plain-film radiography, the adenoidal-nasopharyngeal ratio (AN ratio), side effects, cost of treatment, and beneficial effects after discontinuation of treatment were evaluated for all patients.

Results

Duration of sleep apnea was significantly reduced in the IMFG compared with the MG (p=0.0145, q=9.262). Modafinil and intranasal mometasone furoate both had moderate effects on improvement of the OSAHS score. The IMFG showed a significantly greater beneficial effect on the AN ratio when compared with the MG (p=0.0001, q=6.584). No adverse events of treatment with modafinil and intranasal mometasone furoate were reported. Cost of treatment and beneficial effect after discontinuation were both significantly greater for the IMFG compared with the MG.

Conclusions

The findings of this preliminary clinical study were that for patients diagnosed with OSAHS, night-time treatment with intranasal mometasone furoate was more effective than modafinil.