Comparison of intranasal versus intravenous midazolam for management of status epilepticus in dogs: A multi-center randomized parallel group clinical study

Background

The intranasal (IN) route for rapid drug administration in patients with brain disorders, including status epilepticus, has been investigated. Status epilepticus is an emergency, and the IN route offers a valuable alternative to other routes, especially when these fail.

Objectives

To compare IN versus IV midazolam (MDZ) at the same dosage (0.2 mg/kg) for controlling status epilepticus in dogs.

Animals

Client‐owned dogs (n = 44) with idiopathic epilepsy, structural epilepsy, or epilepsy of unknown origin manifesting as status epilepticus.

Methods

Randomized parallel group clinical trial. Patients were randomly allocated to the IN‐MDZ (n = 21) or IV‐MDZ (n = 23) group. Number of successfully treated cases (defined as seizure cessation within 5 minutes and lasting for ≥10 minutes), seizure cessation time, and adverse effects were recorded. Comparisons were performed using the Fisher's exact and Wilcoxon rank sum tests with statistical significance set at α < .05.

Results

IN‐MDZ and IV‐MDZ successfully stopped status epilepticus in 76% and 61% of cases, respectively (P = .34). The median seizure cessation time was 33 and 64 seconds for IN‐MDZ and IV‐MDZ, respectively (P = .63). When the time to place an IV catheter was taken into account, IN‐MDZ (100 seconds) was superior (P = .04) to IV‐MDZ (270 seconds). Sedation and ataxia were seen in 88% and 79% of the dogs treated with IN‐MDZ and IV‐MDZ, respectively.

Conclusions and Clinical Importance

Both routes are quick, safe, and effective for controlling status epilepticus. However, the IN route demonstrated superiority when the time needed to place an IV catheter was taken into account.

Treatment of congenital extrahepatic portosystemic shunts in dogs: A systematic review and meta-analysis

Background

Several options have been proposed for the treatment of congenital extrahepatic portosystemic shunts (cEHPSS) in dogs, but formal comparisons among different treatment options are currently unavailable. A previous evidence‐based review (2012) found low quality of evidence for papers assessing the treatment of cEHPSS in dogs.

Objectives

To assess the quality of evidence available in the treatment of cEHPSS, summarize the current state of knowledge with respect to outcome after cEHPSS management, and compare different treatment techniques.

Animals

Not used.

Methods

A bibliographic search was performed without date or language restrictions. Studies were assessed for quality of evidence (study design, study group sizes, subject enrollment quality, and overall risk of bias) and outcome measures reported (perioperative outcome, clinical outcome, and surgical or interventional outcome), all reported with 95% confidence intervals. A network meta‐analysis was performed.

Results

Forty‐eight studies were included. Six retrospective studies (grade 4b) compared 2 techniques and 7 were abstracts (grade 5). The quality of evidence was low and risk of bias high. Regarding surgical outcome, statistically significant superiority of ameroid constrictor over thin film band was observed (P = .003). No other comparisons were statistically significant.

Conclusions and Clinical Importance

The evidence base of choice of treatment of cEHPSS in dogs remains weak despite recent publications on the subject. Ameroid is superior to thin film band in causing EHPSS closure. Blinded randomized studies comparing different treatment modalities, which routinely include postoperative imaging to assess cEHPSS closure and acquired portosystemic shunt development are essential.

Systematic review of antiepileptic drugs' safety and effectiveness in feline epilepsy

BACKGROUND

Understanding the efficacy and safety profile of antiepileptic drugs (AEDs) in feline epilepsy is a crucial consideration for managing this important brain disease. However, there is a lack of information about the treatment of feline epilepsy and therefore a systematic review was constructed to assess current evidence for the AEDs' efficacy and tolerability in cats. The methods and materials of our former systematic reviews in canine epilepsy were mostly mirrored for the current systematic review in cats. Databases of PubMed, CAB Direct and Google scholar were searched to detect peer-reviewed studies reporting efficacy and/or adverse effects of AEDs in cats. The studies were assessed with regards to their quality of evidence, i.e. study design, study population, diagnostic criteria and overall risk of bias and the outcome measures reported, i.e. prevalence and 95% confidence interval of the successful and affected population in each study and in total.

RESULTS

Forty studies describing clinical outcomes of AEDs' efficacy and safety were included. Only two studies were classified as "blinded randomised controlled trials". The majority of the studies offered high overall risk of bias and described low feline populations with unclear diagnostic criteria and short treatment or follow-up periods. Individual AED assessments of efficacy and safety profile showed that phenobarbital might currently be considered as the first choice AED followed by levetiracetam and imepitoin. Only imepitoin's safety profile was supported by strong level of evidence. Imepitoin's efficacy as well as remaining AEDs' efficacy and safety profile were supported by weak level of evidence.

CONCLUSIONS

This systematic review reflects an evidence-based assessment of the published data on the AEDs' efficacy and safety for feline epilepsy. Currently, phenobarbital is likely to be the first-line for feline epileptic patients followed by levetiracetam and imepitoin. It is essential that clinicians evaluate both AEDs' effectiveness and tolerability before tailoring AED to the individual patient. Further studies in feline epilepsy treatment are by far crucial in order to establish definite guidelines for AEDs' efficacy and safety.

Intranasal Midazolam versus Rectal Diazepam for the Management of Canine Status Epilepticus: A Multicenter Randomized Parallel-Group Clinical Trial

Background

Intranasal administration of benzodiazepines has shown superiority over rectal administration for terminating emergency epileptic seizures in human trials. No such clinical trials have been performed in dogs.

Objective

To evaluate the clinical efficacy of intranasal midazolam (IN‐MDZ), via a mucosal atomization device, as a first‐line management option for canine status epilepticus and compare it to rectal administration of diazepam (R‐DZP) for controlling status epilepticus before intravenous access is available.

Animals

Client‐owned dogs with idiopathic or structural epilepsy manifesting status epilepticus within a hospital environment were used. Dogs were randomly allocated to treatment with IN‐MDZ (n = 20) or R‐DZP (n = 15).

Methods

Randomized parallel‐group clinical trial. Seizure cessation time and adverse effects were recorded. For each dog, treatment was considered successful if the seizure ceased within 5 minutes and did not recur within 10 minutes after administration. The 95% confidence interval was used to detect the true population of dogs that were successfully treated. The Fisher's 2‐tailed exact test was used to compare the 2 groups, and the results were considered statistically significant if P < .05.

Results

IN‐MDZ and R‐DZP terminated status epilepticus in 70% (14/20) and 20% (3/15) of cases, respectively (P = .0059). All dogs showed sedation and ataxia.

Conclusions and Clinical Importance

IN‐MDZ is a quick, safe and effective first‐line medication for controlling status epilepticus in dogs and appears superior to R‐DZP. IN‐MDZ might be a valuable treatment option when intravenous access is not available and for treatment of status epilepticus in dogs at home.

Epileptic Seizures Versus Syncope: Pathophysiology and Clinical Approach

<p>Generalised epileptic seizures and syncope are two syndromes with similar clinical manifestation and their differentiation can be quite challenging. The aim of this review is to use an evidence-based approach in differentiating these two syndromes through the comprehension of the pathophysiological mechanisms involved and their clinical signs. Both syndromes affect regions of the forebrain and consciousness level, although, different mechanisms are involved. Syncope is a paroxysmal event secondary to a short-term decrease in cerebral perfusion, oxygenation or essential nutrients delivery. Generalised epileptic seizure activity is defined as the clinical manifestation of transient paroxysmal disturbances in brain function secondary to an imbalance between excitatory and inhibitory neurotransmitters. Clinical criteria, including precipitating events, clinical signs preceding, during and following the episodes and event duration, can be used to differentiate the two syndromes. Although these criteria might be useful for the practitioner, definite conclusions should be precluded due to the lack of original research articles and weak evidence on this specific field.</p><p><strong>Application:</strong> The review might be a useful tool for the general practitioner and clinical scientist as it will aid towards the differentiation of two syndromes, i.e. generalised epileptic seizures and syncope, with similar clinical presentation.</p><br /> <img src="https://www.veterinaryevidence.org/rcvskmod/icons/oa-icon.jpg" alt="Open Access" /> <img src="https://www.veterinaryevidence.org/rcvskmod/icons/pr-icon.jpg" alt="Peer Reviewed" />

Antiepileptic Drugs’ Tolerability and Safety – a Systematic Review and Meta-analysis of Adverse Effects in Dogs

<p>Various anti-epileptic drugs (AEDs) are used for the management of idiopathic epilepsy (IE) in dogs. Their safety profile is an important consideration for regulatory bodies, owners and prescribing clinicians. However, information on their adverse effects still remains limited with most of it derived from non-blinded non-randomized uncontrolled trials and case reports.</p><p><span>This poster won third place, which was presented at the Veterinary Evidence Today conference, Edinburgh November 1-3, 2016. </span></p><br /> <img src="https://www.veterinaryevidence.org/rcvskmod/icons/oa-icon.jpg" alt="Open Access" />

Antiepileptic drugs' tolerability and safety--a systematic review and meta-analysis of adverse effects in dogs

Background

The safety profile of anti-epileptic drugs (AEDs) is an important consideration for the regulatory bodies, owners and prescribing clinicians. Information on their adverse effects still remains limited. A systematic review including a meta-analytic approach was designed to evaluate existing evidence for the safety profile of AEDs in canine patients. Electronic searches of PubMed, CAB Direct and Google scholar were carried out without date or language restrictions. Conference proceedings were also searched. Peer-reviewed full-length studies reporting adverse effects of AEDs in epileptic and healthy non-epileptic dogs were included. Studies were allocated to three groups based on their design. Individual studies were evaluated based on the quality of evidence (study design, study group sizes, subject enrolment quality and overall risk of bias) and the outcome measures reported (proportion of specific adverse effects for each AED, prevalence and 95 % confidence interval of the affected population in each study and comparative odds ratio of adverse effects for AEDs).

Results

Ninety studies, including six conference proceedings, reporting clinical outcomes of AEDs’ adverse effects were identified. Few studies were designed as blinded randomised controlled clinical trials. Many studies included low canine populations with unclear criteria of subject enrolment and short treatment periods. Direct comparisons suggested that imepitoin and levetiracetam might have a better safety profile than phenobarbital, whilst the latter might have a better safety profile than potassium bromide. However, none of these comparisons showed a statistically significant difference. Comparisons between other AEDs were not possible as a considerable amount of studies lacked power calculations or adequate data to allow further statistical analysis. Individual AED assessments indicated that levetiracetam might be one of the safest AEDs, followed by imepitoin and then phenobarbital and potassium bromide; these findings were all supported by a strong level of evidence. The safety profile in other AEDs was variable, but weak evidence was found to permit firm conclusions or to compare their safety to other AEDs.

Conclusions

This systematic review provides objective evaluation of the most commonly used AEDs’ adverse effects. Adverse effects usually appeared mild in all AEDs and subsided once doses and/or serum levels were monitored or after the AED was withdrawn. Although phenobarbital might be less safe than imepitoin and levetiracetam, there was insufficient evidence to classify it as an AED with a high risk of major adverse effects. It is important for clinicians to evaluate both AEDs’ effectiveness and safety on an individual basis before the selection of the appropriate monotherapy or adjunctive AED therapy.

The Evidence Behind the Treatment of Canine Idiopathic Epilepsy

Oral phenobarbital and imepitoin in particular, followed by potassium bromide and levetiracetam are likely to be effective for the treatment of canine idiopathic epilepsy. There is strong evidence supporting the use of oral phenobarbital and imepitoin as ‘first line’ medications. However, there remains a lack of evidence for targeted treatment for the various individual epileptic phenotypes and quite limited evidence on direct comparisons of the efficacy between various anti-epileptic drugs.

The Evidence Behind the Diagnostic Investigation of Canine Idiopathic Epilepsy

Clinical bottom line There remains until recently an overall lack of clarity for the practical criteria for the diagnosis of canine idiopathic epilepsy. Signalment and an interictal neurological examination are vital for the diagnosis of idiopathic epilepsy. Despite the current insufficient evidence, the emerge of new diagnostic methods, such as cerebrospinal fluid and/or serum biomarkers, advanced functional neuroimaging techniques and electroencephalography, is likely to change the diagnostic approach in canine epilepsy in the near future.

Surgery in Epilepsy – How Advances in Human Neurology can benefit Veterinary Patients

<p>This editorial article reports the evidence behind the pre-surgical evaluation and epilepsy surgey in human patients with drug-resistant idiopathic epilepsy and how this could potentially benefit veterinary patients.</p><p>(Editorial article - Abstract not applicable)</p>

Inter-observer agreement of canine and feline paroxysmal event semiology and classification by veterinary neurology specialists and non-specialists

Background

Advances in mobile technology mean vets are now commonly presented with videos of paroxysmal events by clients, but the consistency of the interpretation of these videos has not been investigated. The objective of this study was to investigate the level of agreement between vets (both neurology specialists and non-specialists) on the description and classification of videos depicting paroxysmal events, without knowing any results of diagnostic workup. An online questionnaire study was conducted, where participants watched 100 videos of dogs and cats exhibiting paroxysmal events and answered questions regarding: epileptic seizure presence (yes/no), seizure type, consciousness status, and the presence of motor, autonomic and neurobehavioural signs. Agreement statistics (percentage agreement and kappa) calculated for each variable, with prevalence indices calculated to aid their interpretation.

Results

Only a fair level of agreement (κ = 0.40) was found for epileptic seizure presence. Overall agreement of seizure type was moderate (κ = 0.44), with primary generalised seizures showing the highest level of agreement (κ = 0.60), and focal the lowest (κ =0.31). Fair agreement was found for consciousness status and the presence of autonomic signs (κ = 0.21–0.40), but poor agreement for neurobehavioral signs (κ = 0.16). Agreement for motor signs ranged from poor (κ = ≤ 0.20) to moderate (κ = 0.41–0.60). Differences between specialists and non-specialists were identified.

Conclusions

The relatively low levels of agreement described here highlight the need for further discussions between neurology experts regarding classifying and describing epileptic seizures, and additional training of non-specialists to facilitate accurate diagnosis. There is a need for diagnostic tools (e.g. electroencephalogram) able to differentiate between epileptic and non-epileptic paroxysms.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-015-0356-2) contains supplementary material, which is available to authorized users.

Treatment in canine epilepsy--a systematic review

Background

Various antiepileptic drugs (AEDs) are used for the management of canine idiopathic epilepsy (IE). Information on their clinical efficacy remains limited. A systematic review was designed to evaluate existing evidence for the effectiveness of AEDs for presumptive canine IE. Electronic searches of PubMed and CAB Direct were carried out without date or language restrictions. Conference proceedings were also searched. Peer-reviewed full-length studies describing objectively the efficacy of AEDs in dogs with IE were included. Studies were allocated in two groups, i.e. blinded randomized clinical trials (bRCTs), non-blinded randomized clinical trials (nbRCTs) and non-randomized clinical trials (NRCTs) (group A) and uncontrolled clinical trials (UCTs) and case series (group B). Individual studies were evaluated based on the quality of evidence (study design, study group sizes, subject enrolment quality and overall risk of bias) and the outcome measures reported (in particular the proportion of dogs with ≥50% reduction in seizure frequency).

Results

Twenty-six studies, including two conference proceedings, reporting clinical outcomes of AEDs used for management of IE were identified. Heterogeneity of study designs and outcome measures made meta-analysis inappropriate. Only four bRCTs were identified in group A and were considered to offer higher quality of evidence among the studies. A good level of evidence supported the efficacy of oral phenobarbital and imepitoin and fair level of evidence supported the efficacy of oral potassium bromide and levetiracetam. For the remaining AEDs, favorable results were reported regarding their efficacy, but there was insufficient evidence to support their use due to lack of bRCTs.

Conclusions

Oral phenobarbital and imepitoin in particular, as well as potassium bromide and levetiracetam are likely to be effective for the treatment of IE. However, variations in baseline characteristics of the dogs involved, significant differences between study designs and several potential sources of bias preclude definitive recommendations. There is a need for greater numbers of adequately sized bRCTs evaluating the efficacy of AEDs for IE.

Perturbations to the IGF1 growth pathway and adult energy homeostasis following disruption of mouse chromosome 12 imprinting

Aim

Disruption to insulin-like growth factor (IGF) signalling pathways during early life causes growth retardation and defects of developing metabolic organs that can alter set points of energy homeostasis for a lifetime. Inheritance of two maternal copies of human chromosome 14q32.2 (Temple syndrome) causes severe foetal growth retardation and post-natal failure to thrive. Disruption of imprinted gene dosage in the orthologous region on mouse chromosome 12 also affects growth. Here, we investigated whether altering chromosome 12-imprinted gene dosage can affect IGF signalling.

Methods

We investigated mice with a transgene insertion at the imprinted domain of chromosome 12. This lesion causes misexpression of neighbouring genes such that the expression of non-coding RNAs is elevated, and levels of delta-like homologue 1 (Dlk1), retrotransposon-like 1 (Rtl1) and deiodinase 3 (Dio3) transcripts are reduced.

Results

We observed three key phenotypes in these mice: (i) embryonic growth retardation associated with altered expression of IGF1 binding proteins, (ii) peri-natal failure to thrive accompanied by hypothyroidism and low serum IGF1. Unexpectedly this phenotype was growth hormone independent. (iii) Adult animals had reduced glucose tolerance as a result of endocrine pancreatic insufficiency.

Conclusions

We propose that all of these phenotypes are attributable to impaired IGF action and show for the first time that the chromosome 12 cluster in the mouse is an imprinted locus that modulates the IGF signalling pathway. We propose that growth retardation observed in human Temple syndrome might have a similar cause.

Fitness trade-offs and the maintenance of alternative male morphs in the bulb mite (Rhizoglyphus robini)

Alternative reproductive phenotypes (ARPs) occur across a wide range of taxa. Most ARPs are conditionally expressed in response to a cue, for example body size, that reliably correlates with the status of the environment: individuals below the (body size) threshold then develop into one morph, and individuals above the threshold develop into the alternative morph. The environmental threshold model provides a theoretical framework to understand the evolution and maintenance of such ARPs, yet no study has examined the underlying fitness functions that are necessary to realize this. Here, we empirically examined fitness functions for the two male morphs of the bulb mite (Rhizoglyphus robini). Fitness functions were derived in relation to male size for solitary males and in relation to female size under competition. In both cases, the fitness functions of the two morphs intersected, and the resulting fitness trade-offs may play a role in the maintenance of this male dimorphism. We furthermore found that competition was strongest between males of the same morph, suggesting that fitness trade-off in relation to male size may persist under competition. Our results are a first step towards unravelling fitness functions of ARPs that are environmentally cued threshold traits, which is essential for understanding their maintenance and in explaining the response to selection against alternative morphs.

In vitro methylation of specific regions in recombinant DNA constructs by excision and religation

The first imprinted genes were identified in the early 1990s (e.g., refs. 1,2) and there are now over 40 mammalian genes known to be regulated by genomic imprinting (for an up-to-date list, see ref. 3). The details of the mechanism that discriminates between the active and silent alleles of these genes, based on their parent of origin, may differ from one imprinted gene to the next, but must include some form of epigenetic mark that distinguishes alleles that have passed through the male or female germline (4-7). The addition of methyl groups to cytosine residues of CpG dinucleotides might provide such a mark, since regions of differential methylation have been identified in the vicinity of many of the known imprinted genes (8,9). Moreover, analysis of imprinted gene expression in a methyltransferase knockout (Dnmt1(-/-)) mouse has shown that the imprint is lost in a number of cases, resulting in either two silent alleles (Igf2, Igf2r and Kvlqt) or two expressed alleles (H19, p57(kip2), Snrpn, and Xist) (4,10-12). Although there may be exceptions (for instance, imprinted expression of Mash2 is maintained in Dmnt1(-/-) embryos; ref. 13), differential methylation is likely to be an important aspect of the imprinting mechanism that is relevant to most of the imprinted genes in mammals. There is accumulating evidence that methylation is also important for the imprinting of plant genes (reviewed in ref. 14).

A study of the flood events in Cyprus

Abstract. Almost every year, localised and in some cases more widespread floodings affect parts of Cyprus, causing damages to properties destruction to infrastructure and housing and sometimes the loss of human life. Various factors such as the meteorological situation and type and intensity of precipitation, the geomorphology, the geology and the human intervention to geomorphology are responsible for flood events. In the present study, only the meteorological situation and the associated mechanisms are examined in an attempt to gain the essential knowledge for improvement of local weather forecasts. The study period covers a thirteen-year period, from 1994 to 2006, in which 43 cases of flooding were reported, mainly over urbanized areas. The dominant favorable weather conditions for flood events are either the existence of a depression or weather conditions of convectional type. According to these two factors, the flood events were classified into two categories; the "instability'' category which includes isolated flood events of short duration, and the "depression'' category which includes widespread flood events of long duration.

Vertigo and imbalance caused by a small lesion in the anterior insula

The exact location of the vestibular cortex in humans has not yet been established. Isolated lesions in the insula are exceptional. We describe a patient with recurrent episodes of vertigo and imbalance following a small lesion in the anterior insula. Myogenic and neurogenic vestibular evoked potentials were both performed using auditory stimuli. The former was recorded from the sternocleidomastoid muscle and the latter from the parietal areas on the scalp. Brainstem auditory evoked potentials, threshold latency series, pure tone audiometry and video nystagmography were also performed, as was brain MRI. All evoked potential studies and pure tone audiometry were within normal limits, ruling out peripheral and brainstem causes for the patient's symptoms. Video nystagmography revealed high slow phase velocities bilaterally with caloric stimulation, and saccadic tracking on the smooth pursuit examination. The MRI revealed a small lesion in the right anterior insula. To our knowledge this is the first reported case of vestibular symptoms and signs from a lesion in the anterior insula on MRI. In addition, its effects on the nystagmogram suggest that this area may be part of the pathway that controls smooth pursuit.