Evaluating Pain and Analgesia Effectiveness Following Routine Castration in Rabbits Using Behavior and Facial Expressions.

Prevention of pain in rabbits is a priority for both welfare and validity of scientific data. We aimed to determine if the rabbit grimace scale (RbtGS) could be used as a viable, rapid assessment tool in two breeds of rabbit, Dutch belted (DB) and New Zealand white (NZW), following orchidectomy, as an adjunct to behavioral analysis. All animals received analgesia. Rabbits were filmed and their behavior was recorded at multiple time points pre- and post-orchidectomy. Observers then scored specific pain associated behaviors for analysis. Time matched footage was also scored using the rabbit grimace scale (RbtGS). Following surgery, rabbits showed significant increases in the duration spent displaying key pain associated behaviors at 1 and 5 h post-surgery. DB rabbits that received low dose meloxicam (0.2 mg/kg) showed significantly more pain behaviors at 1 and 5 h post-surgery compared to those administered a combination of higher dose meloxicam (0.6 mg/kg) and a lidocaine/bupivacaine local infusion. DB rabbits showed an increase in RbtGS score at both 1 and 5 h post-surgery. In the NZW rabbits, an increase in RbtGS score was only observed at 1 h post-surgery. Using behavioral analysis as the gold standard for comparison, the RbtGS was an effective means of determining when rabbits are painful following orchidectomy. Higher dose meloxicam (0.6 mg/kg) combined with local anesthetic was a more effective method of reducing pain, compared to lower dose meloxicam (0.2 mg/kg) alone.

Welfare Assessment, End-Point Refinement and the Effects of Non-Aversive Handling in C57BL/6 Mice with Lewis Lung Cancer.

Cancer-bearing mice are at risk of developing anxiety, pain, or malaise. These conditions may not only harm welfare but could also undermine data quality and translational validity in studies to develop therapeutic interventions. We aimed to establish whether, or at what point mice developing lung cancer show these symptoms, what measures can best detect their onset, and if data quality and animal welfare can be enhanced by using non-aversive handling (NAH). Welfare was monitored using various daily methods. At the beginning and end of the study, we also scored behaviour for general welfare evaluation, recorded nociceptive thresholds, and applied the mouse grimace scale (MGS). Cancer caused a decline in daily welfare parameters (body weight, and food and water consumption) beginning at around 4 days prior to euthanasia. As cancer progressed, rearing and walking declined to a greater extent in cancer-bearing versus control mice, while grooming, inactive periods, and MGS scores increased. A decline in nest building capability and food consumption provided a particularly effective means of detecting deteriorating welfare. These changes suggested a welfare problem arose as cancer developed, so similar studies would benefit from refinement, with mice being removed from the study at least 4 days earlier. However, the problem of highly varied tumour growth made it difficult to determine this time-point accurately. There were no detectable beneficial effects of NAH on either data quality or in terms of enhanced welfare.

Analgesics promote welfare and sustain tumour growth in orthotopic 4T1 and B16 mouse cancer models.

Murine orthotopic cancer models often require surgery, potentially causing pain or distress. However, analgesics are often withheld because they may alter tumour development. Two orthotopically implanted cancers were investigated in mice pre-treated with meloxicam (10 mg/kg), buprenorphine (0.2 mg/kg) or saline (1 ml/kg). Tumours were imaged and welfare was assessed using body weight, behaviour and nociceptive responses. In study 1, BALB/c mice were inoculated with 4T1 mammary carcinoma or saline during surgery or anaesthesia. As pre-treatment with a single buprenorphine dose appeared beneficial to cancer growth consistency, a second cohort of mice additionally received saline or buprenorphine at 12 and 24 h. Surgery resulted in increased mammary tumour growth and lung metastases. These unwanted effects were lessened by buprenorphine pre-treatment, especially when given repeatedly. Mammary tumour-bearing mice became less active and nociceptive thresholds declined over time, indicating some discomfort as tumours grew. In study 2, C57BL/6 mice received B16 melanoma. This non-surgical model was used to determine whether meloxicam or buprenorphine affected cancer seeding of the lungs. While meloxicam reduced B16 lung seeding, buprenorphine did not. Mechanical thresholds decreased as cancer developed in mice bearing melanoma, but the magnitude of this was insufficient to conclude that there were any significant welfare concerns. This study highlights the scientific value in utilising non-surgical models, where possible. When surgery must be performed at the time of tumour inoculation, the effects of this should be controlled with appropriate analgesics to enhance the value and possibly translation of the research.

Pacing as a Treatment for Reflex-Mediated (Vasovagal, Situational, or Carotid Sinus Hypersensitivity) Syncope: A Systematic Review for the 2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society.

OBJECTIVES: To determine, using systematic review of the biomedical literature, whether pacing reduces risk of recurrent syncope and relevant clinical outcomes among adult patients with reflex-mediated syncope. METHODS: MEDLINE (through PubMed), EMBASE, and the Cochrane Central Register of Controlled Trials (through October 7, 2015) were searched for randomized trials and observational studies examining pacing and syncope, and the bibliographies of known systematic reviews were also examined. Studies were rejected for poor-quality study methods and for the lack of the population, intervention, comparator, or outcome(s) of interest. RESULTS: Of 3188 citations reviewed, 10 studies met the inclusion criteria for systematic review, including a total of 676 patients. These included 9 randomized trials and 1 observational study. Of the 10 studies, 4 addressed patients with carotid sinus hypersensitivity, and the remaining 6 addressed vasovagal syncope. Among the 6 open-label (unblinded) studies, we found that pacing was associated with a 70% reduction in recurrent syncope (relative risk [RR]: 0.30; 95% confidence interval [CI]: 0.15-0.60). When the 2 analyzable studies with double-blinded methodology were considered separately, there was no clear benefit (RR: 0.73; 95% CI: 0.25-2.1), but confidence intervals were wide. The strongest evidence was from the randomized, double-blinded ISSUE-3 (Third International Study on Syncope of Uncertain Etiology) trial, which demonstrated a benefit of pacing among patients with recurrent syncope and asystole documented by implantable loop recorder. CONCLUSIONS: There are limited data with substantive evidence of outcome ascertainment bias, and only 2 studies with a double-blinded study design have been conducted. The evidence does not support the use of pacing for reflex-mediated syncope beyond patients with recurrent vasovagal syncope and asystole documented by implantable loop recorder.

Reassessment of Cardiac Function and Implantable Cardioverter-Defibrillator Use Among Medicare Patients With Low Ejection Fraction After Myocardial Infarction.

BACKGROUND: Guidelines recommend that patients with low ejection fraction (EF) after myocardial infarction (MI) have their EF reassessed 40 days after MI for implantable cardioverter-defibrillator (ICD) candidacy. This study examines rates of EF reassessment and their association with 1-year ICD implantation in post-MI patients with low EF. METHODS: We examined rates of postdischarge EF reassessment and ICD implantation among 10 289 Medicare-insured patients ≥65 years of age with an EF≤35% during the index MI admission from January 2007 through September 2010 in ACTION Registry-GWTG (Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With The Guidelines). Multivariable Cox models tested the association between time-dependent EF reassessment and 1-year ICD implantation, stratified by revascularization status during the index MI admission. RESULTS: Among patients with EF ≤35% during the index MI admission, 66.8% (95% confidence interval [CI], 65.9-67.8) had EF reassessment within the next year. Revascularized patients were more likely to have EF reassessment (76.9% [95% CI, 75.8-78.0)] versus 53.7% [95% CI, 52.2-55.2]; P<0.001) and had shorter times to EF reassessment (median, 67 versus 84 days; P<0.001) than nonrevascularized patients. Among patients with EF reassessment, only 11% received an ICD within 1 year. Reassessment of EF was associated with a higher likelihood of ICD implantation for both revascularized (unadjusted, 12.1% versus 2.4%, P<0.001; adjusted hazard ratio, 10.6, 95% CI, 7.7-14.8) and nonrevascularized (unadjusted, 10.0% versus 1.7%, P<0.001; adjusted hazard ratio, 6.1, 95% CI, 4.1-9.2) patients. CONCLUSIONS: In US practice, EF reassessments are commonly performed among patients with MI with an initially reduced EF. Although 1-year EF reassessment is associated with increased likelihood of ICD implantation, 1-year ICD implantation rates remain very low even among patients with EF reassessment, regardless of revascularization status.

Association of hospital myocardial infarction volume with adherence to American College of Cardiology/American Heart Association performance measures: Insights from the National Cardiovascular Data Registry.

BACKGROUND: Adherence to guideline-based therapy improves patient outcomes after acute myocardial infarction (AMI) and hospital AMI volume is associated with reperfusion care, but the extent hospital AMI volume is associated with overall guideline adherence is unclear. METHODS AND RESULTS: We studied 486 hospitals treating 249,877 AMI patients in ACTION Registry-GWTG from January 1, 2007, to March 31, 2011. Hospital adherence to each American College of Cardiology/American Heart Association performance measure was compared between tertiles defined by hospital AMI volume: low (≤108 cases/y), middle (≥109 and ≤227 cases/y), and high (≥228 cases/y). Multivariable logistic regression, adjusting for patient and hospital characteristics, was used to examine the association between annual AMI volume and adherence to each measure. Similar modeling was used to evaluate the relationship between AMI volume and in-hospital mortality. Compared with high-volume hospitals, lower-volume hospitals were less likely to be academically affiliated, or to have cardiac surgery capabilities, electronic health records, or dedicated tobacco treatment services. Higher-volume hospitals had greater adherence to each performance measure, except aspirin use at arrival and reperfusion therapy. The greatest difference was in the rates of referral to cardiac rehabilitation (59%, 76%, and 83% in low-, middle-, and high-volume hospitals, respectively). After multivariable adjustment, higher AMI volume (up to 400 AMI patients/y) remained associated with higher-performance measure adherence. There was no association between AMI volume and in-hospital mortality after adjusting for patient and hospital characteristics. CONCLUSIONS: Higher hospital AMI volume was correlated with better adherence to process of care measures, but not in-hospital mortality.

Using the mouse grimace scale and behaviour to assess pain in CBA mice following vasectomy.

Mice used in biomedical research should have pain reduced to an absolute minimum through refinement of procedures or by the provision of appropriate analgesia. Vasectomy is a common and potentially painful surgical procedure carried out on male mice to facilitate the production of genetically modified mice. The aim of our study was to determine if 0.05 mg/kg buprenorphine would ameliorate pain associated changes following abdominal vasectomy and to determine if the mouse grimace scale is an appropriate tool for the assessment of pain in this model. Eight male CBA mice underwent abdominal vasectomy as part of a genetically modified mouse-breeding programme. Here we assessed pain using a previously validated behaviour-based method and the mouse grimace scale. All mice received buprenorphine (0.05 mg/kg s.c.) pre-surgery. Behaviour and grimace scores were compared between baseline (pre-surgery), 30 min, 5 h, 24 h and 25 h post surgery. Following 24 h post-op, all mice were administered 5 mg/kg meloxicam (s.c.) as additional analgesia. Significant increases in specific pain behaviours and mouse grimace scale score were found 30 min post surgery. At 5 h post surgery, scores were returning to baseline levels. Frequency of rearing was significantly decreased at both 30 min and 5 h post surgery compared to baseline, demonstrating a longer lasting change in normal exploratory behaviour. Buprenorphine (0.05 mg/kg) was ineffective at ameliorating these pain-associated changes in CBA mice and should be considered inadequate at this dose. By 24 h post surgery, pain associated behaviours, grimace scale and rearing had all returned to baseline levels. There was no change in pain behaviours or MGS following administration of meloxicam indicating that an additional dose of meloxicam does not appear to offer benefit at this point. Using the mouse grimace scale to assess pain in mice, appeared to be effective in the immediate post vasectomy period in CBA mice demonstrating the same duration of increased score as the pain associated behaviours.

A comparison of abdominal and scrotal approach methods of vasectomy and the influence of analgesic treatment in laboratory mice.

Vasectomized mice are needed in the production of genetically-modified animals. The BVAAWF/FRAME/RSPCA/UFAW Joint Working Group on Refinement recommended that vasectomy should be performed via an incision in the scrotal sac, rather than via laparotomy, arguing that the former could be less painful due to minimal tissue trauma. This study was undertaken to assess the validity of this recommendation. Mice underwent vasectomy via either abdominal or scrotal approach surgery. Mice were filmed for 15 min presurgery and at one, 24 and 48 h postsurgery. Data were obtained using automated behaviour recognition software (HomeCageScan). Meloxicam was administered either alone or combined with acetaminophen prior to surgery. A third group received only saline subcutaneously. Postsurgery behaviour changes were compared between groups at each time point. Exploratory behaviours such as rearing, walking and sniffing were most greatly reduced at one hour following surgery whereas the duration of grooming increased. By 48 h these changes had largely subsided. Results indicated mice undergoing scrotal approach surgery fared better at one hour postsurgery, but the magnitude of this was relatively insignificant compared with the overall effects of surgery. If the observed behaviour changes resulted from pain, results suggested there was no significant advantage of scrotal versus abdominal approach vasectomy. These and other recently obtained data on the effects of non-steroidal anti-inflammatory drugs (NSAIDs) in mice suggest considerably larger doses of these or more potent analgesics, more precise monitoring of surgical outcomes, or a combination of these factors are needed to determine the extent of pain experienced by mice undergoing vasectomy.

The assessment of post-vasectomy pain in mice using behaviour and the Mouse Grimace Scale.

BACKGROUND: Current behaviour-based pain assessments for laboratory rodents have significant limitations. Assessment of facial expression changes, as a novel means of pain scoring, may overcome some of these limitations. The Mouse Grimace Scale appears to offer a means of assessing post-operative pain in mice that is as effective as manual behavioural-based scoring, without the limitations of such schemes. Effective assessment of post-operative pain is not only critical for animal welfare, but also the validity of science using animal models. METHODOLOGY/PRINCIPAL FINDINGS: This study compared changes in behaviour assessed using both an automated system ("HomeCageScan") and using manual analysis with changes in facial expressions assessed using the Mouse Grimace Scale (MGS). Mice (n = 6/group) were assessed before and after surgery (scrotal approach vasectomy) and either received saline, meloxicam or bupivacaine. Both the MGS and manual scoring of pain behaviours identified clear differences between the pre and post surgery periods and between those animals receiving analgesia (20 mg/kg meloxicam or 5 mg/kg bupivacaine) or saline post-operatively. Both of these assessments were highly correlated with those showing high MGS scores also exhibiting high frequencies of pain behaviours. Automated behavioural analysis in contrast was only able to detect differences between the pre and post surgery periods. CONCLUSIONS: In conclusion, both the Mouse Grimace Scale and manual scoring of pain behaviours are assessing the presence of post-surgical pain, whereas automated behavioural analysis could be detecting surgical stress and/or post-surgical pain. This study suggests that the Mouse Grimace Scale could prove to be a quick and easy means of assessing post-surgical pain, and the efficacy of analgesic treatment in mice that overcomes some of the limitations of behaviour-based assessment schemes.

Absence of hair cell protection by exogenous FGF-1 and FGF-2 delivered to guinea pig cochlea in vivo.

Recent findings that glial cell line-derived neurotrophic factor (GDNF), neurotrophin-3 (NT-3), and transforming growth factor a can protect the auditory hair cells from acoustic trauma or aminoglycoside ototoxicity in vivo raise the question of whether other neurotrophic factors can also protect the hair cells in vivo. Fibroblast growth factor-2 (FGF-2) can protect hair cells from neomycin ototoxicity in vitro, and in vivo study has shown upregulation of FGF receptor-3 in the cochlea following noise exposure, suggesting that some FGF family members might play a role in protection or repair of the cochlea from damage. We therefore examined if FGF-1 and FGF-2 chronically delivered to the cochlea prior to noise overstimulation can attenuate noise-induced hair cell damage in vivo under conditions in which GDNF and NT-3 were effective. Pigmented female guinea pigs underwent left scala tympani implantation of a microcannula attached to an osmotic pump filled with artificial perilymph only or containing FGFs (10 or 1 mg/ml FGF-1 or 10 mg/ml FGF-2). They were exposed to noise (4 kHz octave band, 115 dB SPL, 5 hr) 4 days after surgery. Threshold shifts 10 days postexposure were essentially equivalent at all frequencies tested across different treatment groups. No significant difference in threshold shifts was observed between the treated and untreated ears in any of the groups. The extent of hair cell damage was also comparable among the different treatment groups. These findings indicate that exogenous FGF-1 or FGF-2 does not influence noise-induced hair cell damage under the experimental conditions used in this study, suggesting that these FGFs are not good candidates as auditory hair cell protectors in vivo.