Intra-articular administration of lidocaine plus adrenaline in dogs: Pharmacokinetic profile and evaluation of toxicity in vivo and in vitro.

The aim of this study was to evaluate the safety of intra-articular (IA) lidocaine plus adrenaline for improving peri-operative analgesia in anaesthetized dogs undergoing arthroscopy of the elbow. A solution of lidocaine (L) 1.98% plus adrenaline 1:100.000 was administered via the IA route and its safety evaluated in terms of cardio-, neuro-, and chondro-toxicity. No bradycardia or hypotension was recorded from induction to the last observational time point. Signs of toxicity of the nervous system could have been masked by the general anaesthesia but lidocaine concentrations detected in the blood were lower than those thought to be capable of producing toxicity. The assessment of in vitro chondrotoxicity showed a dose- and time-dependent effect of lidocaine on the viability of articular cells. Adrenaline appeared to reduce the chondrotoxicity of 1% lidocaine, following an exposure of up to 30 min.

Comparison of ketamine-dexmedetomidine-methadone and tiletamine-zolazepam-methadone combinations for short-term anaesthesia in domestic pigs.

Cardiorespiratory effects, quality of induction, depth of anaesthesia and quality of recovery were compared in pigs anaesthetised with 8 mg/kg ketamine, 20 µg/kg dexmedetomidine and 0.2 mg/kg methadone (KDM, n = 18) or 8 mg/kg tiletamine-zolazepam and 0.2 mg/kg methadone (TZM, n = 9). Anaesthesia with KDM was partially reversed in nine animals with 0.2 mg/kg atipamezole (KDMat). Sedation was observed earlier in the TZM group (47.2 ± 25.3 s) than the KDM group (91.5 ± 37.4 s). Sternal and lateral recumbency were achieved earlier in the TZM group (76.3 ± 36.5 s and 132.1 ± 30.5 s, respectively) than in the KDM group (149.1 ± 58.7 s and 249.2 ± 84.0 s, respectively). PaO2, SaO2 and PaO2:FiO2 were lower in the TZM group (68.7 ± 4.1 mmHg, 93.4 ± 1.4% and 327.2 ± 19.9 mmHg, respectively) than in the KDM group (80.4 ± 5.9 mmHg, 95.7 ± 1.0% and 380.4 ± 25.6 mmHg, respectively). Fshunt and P(A-a)O2 were higher in the TZM group (24.0 ± 11.8% and 31.4 ± 3.8 mmHg, respectively) than in the KDM group (13.4 ± 3.2% and 20.7 ± 7.4 mmHg, respectively). Times from drug injection to first head movements, sternal recumbency and standing/walking were significantly shorter in the KDM group (45.1 ± 10.5, 48.4 ± 12.6 and 54.4 ± 17.8 min, respectively) than in the TZM group (57.8 ± 11.4, 93.1 ± 14.2 and 165.7 ± 56.6 min, respectively). The median recovery score was higher in the TZM group than in the KDMnoat and KDMat subgroups. Both drug combinations provided adequate anaesthesia for minor procedures lasting about 30 min, but TZM was associated with a poor recovery and oxygenation.

Intra-articular administration of lidocaine in anaesthetized dogs: pharmacokinetic profile and safety on cardiovascular and nervous systems.

The intra-articular administration of lidocaine is a frequent practice in human orthopaedic surgical procedures, but an eventual absorption of the drug into the bloodstream can lead to toxicity, mainly concerning the central nervous system and the cardiovascular systems. The purpose of this study was to determine the pharmacokinetic profile and the safety, in terms of cardiovascular and CNS toxicity, of lidocaine after intra-articular administration to anesthetized dogs undergoing arthroscopy. Lidocaine 2% was administered to eight dogs before surgery in differing amounts, depending on the volume of the joints involved, and blood samples were taken at predetermined time points. The maximum serum concentration of lidocaine ranged from 0.50 to 3.01 µg/mL (mean ± SD: 2.18 ± 0.91 µg/mL), and the time to reach it was 28.75 ± 15.74 min. No signs of cardiac toxicity were detected during the entire procedure, and possible signs of CNS toxicity were masked by the anaesthesia. However, concentrations reported in literature as responsible for neurotoxicity in dog were achieved in three of eight investigated subjects. Pending further studies, veterinarians should consider the possibility of side effects occurring following the intra-articular administration of local anaesthetics.

Immobilization of captive tigers (Panthera tigris) with a combination of tiletamine, zolazepam, and detomidine.

The aims of this study were to evaluate the effects of the administration of a combination of tiletamine-zolazepam and detomidine (TZD) in 9 tigers (Panthera tigris). Nine captive tigers were immobilized with tiletamine-zolazepam and detomidine administered intramuscularly. At the end of the procedure immobilization was partially reversed with atipamezole. Lateral recumbency was achieved in 15.6 ± 5.9 min. The median induction score [scored 1 (excellent) to 4 (poor)] was 1. The immobilization score [scored 1 (poor) to 6 (too deep)] was 5 (4-5) at all study times. After atipamezole administration, all tigers experienced severe ataxia and incoordination. Median recovery score [scored 1 (excellent) to 4 (poor)] was 2.5 (range 2-3). No neurologic and/or important adverse reactions were noticed within 5 days after recovery. The combination tiletamine-zolazepam with detomidine proved to be effective in immobilizing captive healthy tigers but it maybe associated with hypertension and ataxia during recovery. Zoo Biol. 34:40-45, 2015. © 2014 Wiley Periodicals Inc.

Ketamine as a part of anaesthetic management in a dog with twiddler's syndrome.

An 11-year-old male German shepherd dog was referred for possible pacemaker implantation. A routine 6-lead electrocardiogram revealed a third-degree atrio-ventricular block with a heart rate of 40 to 45 beats/minute. A transvenous pacemaker implantation procedure was scheduled. The dog was premedicated with 10 µg/kg acepromazine and 5 mg/kg pethidine. A dose of 5 mg/kg ketamine and 0·2 mg/kg diazepam were used for induction and isoflurane in O2 and a constant rate infusion of ketamine (20 to 30 µg/kg/minute) were administered for maintenance of general anaesthesia. Due to a twiddler's syndrome, the pacemaker had to be repositioned. For the second procedure, the same protocol was employed except for a lower dose of ketamine both for induction (3 mg/kg) and constant rate infusion (10 to 15 µg/kg/minute). Ketamine appeared to be useful for both management of anaesthesia and cardiac pacemaker implantation in the absence of a temporary pacemaker.

Comparison of intra-operative analgesia provided by intravenous regional anesthesia or brachial plexus block for pancarpal arthrodesis in dogs.

The aim of this study was to compare intravenous regional anesthesia (IVRA) and brachial plexus block (BPB) for intra-operative analgesia in dogs undergoing pancarpal arthrodesis (PA). Twenty dogs scheduled for PA were intramuscularly sedated with acepromazine (0.03 mg/kg), general anesthesia was intravenously (IV) induced with thiopental (10 mg/kg) and, after intubation, maintained with isoflurane in oxygen. In 10 dogs (GIVRA) IVRA was performed on the injured limb administering 0.6 ml/kg of 0.5% lidocaine. In 10 dogs (GBPB) the BPB was performed at the axillary level with the help of a nerve stimulator and 0.3 ml/kg of a 1:1 solution of 2% lidocaine and 1% ropivacaine was injected. During surgery fentanyl (0.002 mg/kg IV) was administered if there was a 15% increase of HR and/or MAP compared to the values before surgical stimulation. All the standard cardiovascular and respiratory parameters were continuously monitored during surgery. The duration of surgery and the time of extubation were recorded. Data were compared with a 1-way ANOVA test (P<0.05). No patients required fentanyl administration during surgery. All the recorded parameters were similar in the two groups. The two techniques were similar in providing intra-operative analgesia in dogs undergoing orthopaedic surgery.

Alveolar recruiting maneuver in dogs under general anesthesia: effects on alveolar ventilation, gas exchange, and respiratory mechanics.

The aim of this study was to evaluate the effects of a recruiting maneuver (RM) on lung aeration, gas exchange, and respiratory mechanics during general anesthesia in mechanically ventilated dogs. A thoracic computed tomography (CT) scan, an arterial blood sample, and measurement of respiratory mechanics were performed 10 min before (baseline) and both 5 and 30 min after a vital capacity RM in 10 dogs under general anesthesia. The RM was performed by inflating the lung at 40 cm H(2)O for 20 s. Lung aeration was estimated by analyzing the radiographic attenuation of the CT images. Lung aeration and gas exchange improved significantly 5 min after the RM compared to baseline and returned to values similar to baseline by 30 min. Static lung compliance was not significantly affected by the RM. An RM induces a temporary improvement in lung function in healthy dogs under general anesthesia.

Age-dependent loss of naïve T cells in TCR transgenic bone marrow chimeras.

Study of immune senescence is complicated by low numbers of antigen-specific lymphocytes, particularly naïve T (Tn)cells which disappear with aging. Although T cell receptor (TCR) transgenic mice facilitate aging research, their large number of Ag-specific T cells renders their T cell pool abnormal, precluding normal in vivo immunity. To create a physiologically relevant model with measurable numbers of TCR transgenic CD4+ T cells in the context of normal lymphocytes, mixed (DO11.10+BALB/c) bone marrow (BM) chimeras were constructed. As found in normal mice, the total number of transgenic T cells and the Tn:memory T cell ratio declined with the aging of the BM chimeras. Although these shifts in T cell subsets were evident in both the lymph nodes and the spleen (SP), they were more pronounced in the SP. Unlike DO11.10 mice, transgenic T cells in the chimera acquired an effector/memory phenotype upon antigen challenge. These results reveal a pliable model to study the impact of the constriction of the Tn cell repertoire upon optimal vaccine responses in the elderly.

Differential effects of CD28 costimulation upon cytokine production by CD4+ and CD8+ T cells.

The impact of CD28 ligation upon CD4+ and CD8+ T lymphocyte proliferation and cytokine production was assessed. Although costimulation increased the proliferative response of both T cell subsets, cytokine production was most markedly increased in the CD4+ subset, as evidenced by a 40-fold increase in interleukin-2 (IL-2), a 14-fold increase in interleukin-3 (IL-3) and 5-fold increases in interferon gamma and GM-colony-stimulating factor (CSF) production. The CD8+ T cell response to CD28 ligation was less marked, maxima being a 5-fold increase in IL-2 production and 2-fold increases in IL-3 and GM-CSF production. Resolution of CD4+ and CD8+ T cells into their CD44lo (naïve) and CD44hi (memory/effector) subsets revealed that naive CD4+ T cells were the most CD28-responsive subsets. CD28-mediated costimulation promotes distinct differentiation programs in CD4+ versus CD8+ T cells.

Effects of culture, sex, and age on the distribution of handedness: an evaluation of the sensitivity of three measures of handedness.

The present study examined the effects of culture, age, and sex on three measures of handedness: writing hand, Annett's primary handedness items, and a measure based on hand preference for 11 activities. Using data from a large international study, the relationship between the culture in which participants learned to write (as defined by Hofstede's cultural dimensions) and adult handedness was examined. Participants who learned to write in formal cultures were less likely to be classified as left-handed than those who learned in less formal cultures. Older participants and those who learned to write in formal cultures were more likely to be classified as left-handed by the Annett and 11 item measures than by the writing hand classification. Across measures females were less likely to be classified as left-handed than males. Handedness for writing was found to be more sensitive to cultural influences than the other measures. These results suggest that some measures of handedness may be more sensitive to specific handedness aetiologies than others.

Age-related changes in mature CD4+ T cells: cell cycle analysis.

T cell proliferative responses decrease with age, but the mechanisms responsible are unknown. We examined the impact of age on memory and naive CD4(+) T cell entry and progression through the cell cycle using acridine orange to identify cell cycle stage. For both subsets, fewer stimulated cells from old donors were able to enter and progress through the first cell cycle, with an increased number of cells arrested in G(0) and fewer cells in post G(0) phases. The number of dead cells as assessed by sub-G(0) DNA was also significantly greater in the old group. CD4(+) T cells from old mice also exhibited a significant reduction in clonal history as assessed by CFSE staining. This was associated with a significant decline in cyclin D2 mRNA and protein. We propose that decreases in cyclin D2 are at least partially responsible for the proliferative decline found in aged CD4(+) T cells.

[Endothelin-1 variation in the coronary circulation during angioplasty with a stent implant]. / Variazione di endotelina-1 nel circolo coronarico durante angioplastica con impianto di stent.

Endothelin-1 (ET-1) is an endothelium-derived mediator with vasoconstrictive and mitogenic activity which stimulates vascular smooth muscle cell proliferation. The aim of this study was to evaluate ET-1 production during percutaneous transluminal coronary angioplasty (PTCA) and elective stent implantation. We hypothesized that the additional vessel wall trauma induced by stent deployment might be associated with a greater production of ET-1. To this end, ET-1 levels were measured in 18 patients undergoing PTCA and stenting (12 with left anterior descending coronary artery stenosis and 6 with circumflex artery lesion). The sampling sites were the coronary ostium and coronary sinus in basal conditions (before the procedure), during first balloon inflation, and 5, 20, 60 min after the end of first balloon inflation. At baseline, ET-1 levels were higher in the coronary sinus than in coronary ostium (1.58 +/- 0.22 vs 1.29 +/- 0.20 pg/ml, p < 0.001). During first balloon inflation, ET-1 coronary sinus levels significantly diminished with respect to the basal levels (1.08 +/- 0.32 vs 1.58 +/- 0.22 pg/ml, p < 0.001). Further significant variations of ET-1 levels were not detected neither following the first balloon inflation nor after stent deployment. In conclusion, the culprit lesion seems to produce most of ET-1 circulating in the coronary tree. This is demonstrated by higher ET-1 levels in the coronary sinus compared to coronary ostium at baseline, and even more by the significant ET-1 reduction in the coronary sinus during first balloon inflation. Despite our expectations, we did not detect any significant ET-1 increase during stent deployment.

Effect of alpha-interferon on natural killer cell activity and lymphocyte subsets in thalassemia patients with chronic hepatitis C.

The variation of natural killer (NK) cell activity and lymphocyte subsets 20 h after a single test dose of alpha-IFN, was studied in 17 thalassemic patients with chronic hepatitis C. All patients had suspended the alpha-IFN therapy at least 12 months before the study: 10 were considered responders and 7 nonresponders. Also NK cell cytotoxicity after in vitro incubation with alpha-IFN was studied. The administration of a single dose of alpha-IFN increased NK cell cytotoxic activity significantly in the group of responders and in non-responders; moreover the NK cell cytotoxic activity after alpha-IFN in vitro incubation increased both in responders and nonresponders, but to a lesser degree than in healthy controls. Absolute values of CD4+ and CD8+ lymphocytes decreased significantly only in responders. In conclusion, our data suggest that the variation of NK cytotoxic activity and lymphocyte subsets after a test dose of alpha-IFN can be considered a parameter related to IFN biological effects.

[Interhemispheric epidermoid cyst. A clinical case]. / Cisti epidermoide interemisferica. Caso clinico.

The authors report a rare case of epidermoid cyst with interhemispheric growth closely connected to the anterior portion of the corpus callosum. Although extremely sensitive in determining the site, dimensions and relations of the lesion, NMR does not allow the nature of this pathology to be diagnosed owing to the lack of signal specificity. CT, using the measurement of Hounsfield units, allows a differential diagnosis of epidermoid cysts and arachnoid cysts and lipomas to be made in almost all cases. Treatment is surgical and the complete excision of the capsule avoids recidivation.

[Cerebral amyloid angiopathy (congophilic angiopathy): a rare cause of massive cerebral hemorrhage. Report of an "age-related" sporadic case]. / Angiopatia cerebrale amiloidea (angiopatia congofila): una rara causa di emorragia cerebrale massiva. Osservazione di un caso sporadico "age-related".

Cerebral amyloidosis is a form of organ-limited amyloidosis, which doesn't involve any organ other than brain and which comprises several subtypes, including "congophilic angiopathy" (CA), "senile plaques" (SP), "neurofibrillary degeneration" (ND), "stellate amyloid cores" of spongiform encephalopathies. It is found in 5 to around 20% of human population in people aged 60 to 90 years, the increasing being strictly related to ageing. Usually it is associated to SP and occasionally to ND, being distinguished into familial and non-familial (age-related) variants. It affects intracortical and leptomeningeal variously sized vessels of the brain and is a leading pathogenetic factor in determining a rare but possibly even recurrent form of a massive intraparenchymal cerebral hemorrhage, constituting a 0.2 per cent of brain vascular accidents of any origin and a 5-10 per cent if only primary non traumatic brain hemorrhages are considered. A case of non-familial CA in a previously non-demented nor hypertensive female patient aged 65 years is reported on, who was admitted due to an almost abrupt onset of neurologic symptoms mainly dominated by a sudden loss of consciousness together with a left sensory-motor deficiency syndrome. The patient who had been operated on of unilateral mastectomy eight years earlier due to an invasive ductal carcinoma of the breast was found affected by a devastating brain hemorrhage in the right temporo-occipital lobes with subsequent deflection of the brainstem axis toward the opposite side detected by means of CT/MRI and angiographic investigations.(ABSTRACT TRUNCATED AT 250 WORDS)

Spontaneous haematoma as unusual complication of silastic dural substitute. Report of 2 cases.

Two cases of an unusual complication of synthetic duraplasty are reported. In both cases, patients had been operated on because of meningiomas and dural defects had been repaired with Silastic. Some years later they developed severe graft-related haematomas and were ultimately successfully treated only by the removal of the synthetic grafts. On the basis of this and other clinical experiences, biological dural grafts seem to be preferable to synthetic ones.

Intracerebral venous hemorrhage in "high-risk" carotid-cavernous fistula.

Intracerebral hematoma associated with carotid-cavernous fistula is a rare occurrence. Based on a review of the literature and on the analysis of personal observation, the authors define as "high-risk fistula" a carotid-cavernous fistula at risk of intracerebral hemorrhage. Characteristic features of these are computed tomography demonstration of parenchymal vermicular enhancement of brain vessels, and an angiographic pattern of dilated and tortuous cerebral veins. When an intracerebral hemorrhage occurs in a patient with carotid-cavernous fistula an early but phased and combined neuroradiological-neurosurgical approach is suggested as the best way to treat this life-threatening situation.