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Intramuscular use of alfaxalone in dogs: Why? When? How?

INTRAMUSCULAR USE OF ALFAXALONE IN DOGS

Although Alfaxan® Multidose is not currently licenced in the UK for intramuscular (IM) administration, the clinical benefits it can provide when compared to other IM sedative/induction agents mean it is being used ever more frequently via this route.

This review focuses on how we can utilise IM alfaxalone for sedation in dogs although we also consider some published literature discussing general anaesthesia following IM administration.

AIMS OF SEDATION VIA THE IM ROUTE

The intramuscular administration of sedative and/or anaesthetic agents is occasionally required e.g. for situations where intravenous (IV) access is not immediately possible, either by patient temperament or clinical situation. In dogs, IM alfaxalone offers similar clinical benefits to those observed following IV administration, and similar characteristics to IM use in the cat where combinations of alfaxalone with an opioid, sometimes with the addition of a sedative agent, are an effective choice. For further information on IM use in cats please see Intramuscular use of alfaxalone in cats: Why? When? How?.

One driving force for administering alfaxalone IM is where our main alternative, the alpha-2-agonists, are not considered clinically appropriate due to their well-documented cardiovascular effects, such as for dogs with suspected or diagnosed cardiovascular (CV) disease or haemodynamic instability where the temperament of the patient precludes IV access.

Additionally, alfaxalone administered IM may also be an option to permit IV cannulation in dogs that are still too difficult to handle following routine premedication.

ADMINISTRATION OF ALFAXALONE INTRAMUSCULARLY

ph & VOLUME OF ALFAXAN® MULTIDOSE

To minimise discomfort on administration via the intramuscular route the volume of selected agents should be small and the drugs non-irritant. The neutral pH of Alfaxan Multidose and lack of tissue reaction ensure comfort when administered via the intravenous (Michou et al., 2012), intramuscular (Tamura et al., 2016) routes, or the inadvertent perivascular route (Dugdale, 2010). Diehl et al., (2001) recommended the maximum volume should be 0.25ml/kg per IM site to minimise injection discomfort. To achieve optimal clinical effect and minimise the total volume of alfaxalone required, combinations with other agents should be considered and, if necessary, the dose divided over two or more sites.  Less discomfort is observed following administration into the epaxial musculature compared to other sites e.g. the hind leg.

The time to onset of action and peak effect of most agents following IM administration is slower than via the IV route (Murrell, 2016) and residual drug effects can prolong recovery (Flecknell, 2016).  Additionally, as for any drug administered intramuscularly (or by inadvertent perivascular injection), it is not possible to titrate the dose according to the individual animal’s, and therefore a higher dose than necessary may be administered. As with most drugs the accidental administration subcutaneously, intra-fat, or between fascial planes can lead to poor or inconsistent results.   

ONSET OF ACTION

Alfaxalone is lipophilic, has a high bioavailability and, when administered IM, the rapid tissue absorption results in a swift, dose-dependent, onset of action and depth of neurological depression.  Mean times to onset of lateral recumbency of 3-15 minutes have been reported with peak sedation at approximately 10-15 minutes (Tamura et al., 2015; Tamura et al., 2016; Maney, 2017; Micieli et al, 2019; Murdock et al., 2020). In studies where general anaesthesia was achieved the mean times to intubation were 6-16 minutes (Tamura et al., 2015; Lee et al., 2016; Tamura et al., 2016; Kato et al, 2021).

Induction quality was smooth following IM combinations of alfaxalone with medetomidine and butorphanol (Lee et al., 2016; Kato et al., 2021) and moderately smooth for IM alfaxalone with medetomidine alone, or alfaxalone with butorphanol alone (Kato et al., 2021).

THE EFFECT IS DOSE DEPENDENT

The administration of alfaxalone intramuscularly results in dose-dependent neurological depression (Maney, 2017), induction quality, duration of action and physiological effects (Tamura et al., 2015; Kato et al., 2021).

DURATION OF ACTION

The duration of sedation or unconsciousness will vary with patient physical status, concurrent use of sedatives/opioids, doses administered, and whether any of the components are antagonised.   

In a study by Kato et al. (2021) an IM combination of alfaxalone 2.5mg/kg + medetomidine 5µg/kg + butorphanol 0.3mg/kg resulted in median durations of recumbency of 105 minutes (range 90-130) and endotracheal intubation of 97 minutes (range 84-120). This was similar to the durations of lateral recumbency and intubation of 100 +/- 48 minutes and 60 +/-24 minutes respectively following alfaxalone 2.5mg/kg + medetomidine 2.5µg/kg + butorphanol 0.25mg/kg IM reported by Tamura et al. (2016).  Lee et al. (2015) also studied this combination: alfaxalone 1.5mg/kg, medetomidine 10µg/kg and butorphanol 0.1mg/kg resulted in a mean duration of anaesthesia of 89 +/- 14 minutes.  In 2020 Murdock et al. reported moderate to deep sedation for up to 170 minutes for IM alfaxalone 2mg/kg combined with butorphanol 0.4mg/kg and dexmedetomidine 5µg/kg, and up to 180 minutes following IM alfaxalone 2mg/kg with butorphanol 0.4mg/kg and acepromazine 0.02mg/kg. The authors of the study concluded the extended durations of action may have been the result of the higher dose of butorphanol compared to the other studies.

RECOVERY QUALITY

The combination of alfaxalone with other anaesthetic agents possessing neuro-depressive properties will help ensure good quality of sedation/anaesthesia and a smooth, uneventful recovery (Lee et al, 2016: Tamura et al, 2016; Micieli et al., 2019) with management of the occasional muscle tremors, ataxia or auditory hyperaesthesia reported during recovery following IM alfaxalone alone (Tamura et al., 2015; Maney et al., 2017).  However, consideration should be given to the effects of other drugs co-administered with alfaxalone: occasional muscle twitching can be a consequence of medetomidine administration and dysphoria can following methadone, especially in non-painful patients (Sinclair, 2003; Monteiro et al., 2008).

PHYSIOLOGICAL EFFECTS OF INTRAMUSCULAR ALFAXALONE

CARDIOVASCULAR STABILITY WITH ALFAXALONE

Alfaxalone has an excellent cardiovascular safety profile following IV administration. The baroreceptor reflex is believed to be preserved and, as a result, a stable or mild compensatory increase in heart rate, with a clinically acceptable blood pressure, are observed following administration of alfaxalone (Pasloske, 2005a; Pasloske, 2005b; Muir et al., 2008; Cruz-Benedetti et al., 2018). Cardiac output, peripheral pulses, tissue perfusion and good mucous membrane colour are maintained (Okushima et al., 2014).  Kim et al. (2015) concluded IV alfaxalone 3mg/kg was suitable for echocardiography in healthy dogs and reported no statistically or clinically significant effects on cardiovascular parameters.

Cardiovascular stability following the IM administration of alfaxalone, including maintenance of clinically acceptable blood pressure, has been established by many authors (Lee et al., 2015; Tamura et al., 2015; Tamura et al., 2016; Maney, 2017; Micieli et al., 2019; Kato et al., 2021). In a study by Cruz-Benedetti et al. (2018) a single dose of alfaxalone 4mg/kg produced moderate to deep sedation with maintenance of cardiac output, haemoglobin saturation with oxygen (SpO2) and mean arterial pressure within normal clinical ranges.

When selecting IM protocols the cardiovascular effects of other co-administered agents should be considered e.g. methadone can increase vagal tone and result in bradycardia; alpha-2 agonists produce a transient hypertension, decreased cardiac output and increased circulation time (Sinclair, 2003); ketamine can increase cardiac output and blood pressure via stimulation of the sympathetic nervous system, even in healthy animals (Murrell, 2016).

RESPIRATORY STABILITY

Following the IM administration of alfaxalone spontaneous respiration is well maintained in dogs with no reports of apnoea in studies by Lee et al. (2015); Tamura et al. (2015); Tamura et al. (2016); Micieli et al. (2019); and Kato et al. (2021). Single doses of alfaxalone 1mg/kg and 2mg/kg IM did not result in respiratory depression (Maney et al., 2017) and at 4mg/kg IM there were no significant changes to SpO2 (Cruz-Benedetti et al., 2018). 

The effects of concomitantly administered drugs on the respiratory system were highlighted by Tamura et al. (2016): following IM alfaxalone 2.5mg/kg respiratory rates were maintained, whereas IM medetomidine with butorphanol resulted in a reduced respiratory rate compared to baseline. In the same study, a combination of alfaxalone 2.5mg/kg, medetomidine 2.5µg/kg and butorphanol 0.25mg/kg IM produced no clinically relevant hypoxaemia or hypercapnia.   

USE IN ALL ASA CATEGORIES 

Due to its minimal cardiorespiratory effects, rapid metabolism and smooth recovery, alfaxalone is suitable for administration to all American Society of Anaesthesiologists (ASA) physical status category patients in whom other agents may not be appropriate e.g. those with cardiovascular disease. A discussion of the ASA physical status categories may be accessed here. For a downloadable chart describing the ASA categories please click here

INTRAMUSCULAR ALFAXALONE PROTOCOLS IN THE DOG

ADMINISTRATION WITH OTHER PRODUCTS

The co-administration of agents with sedative and/or analgesic properties produces a dose-sparing effect for each drug and subsequently administered anaesthetic induction and maintenance agents. This was demonstrated by Maddern et al. (2010) who reported a 30% reduction in the dose of IV alfaxalone required to induce general anaesthesia following premedication with medetomidine and butorphanol when compared to premedication with either agent alone, and was confirmed intramuscularly by Kato et al. (2021). In the latter study the combination of medetomidine plus butorphanol reduced the dose of IM alfaxalone necessary to permit endotracheal intubation when compared to alfaxalone in combination with medetomidine alone or butorphanol alone. The dose-sparing effect not only improves patient comfort on IM administration by reducing the volumes required but can also reduce any potential side-effects from each individual agent. For further information please see Perspectives on Premeds - Opioids.

The combination of IM alfaxalone with other agents will help ensure good quality of sedation/anaesthesia and a smooth, uneventful recovery (Lee et al, 2016: Tamura et al, 2016) as described above. IM alpha-2 agonists, opioids and benzodiazepines are often used for sedation (Tamura et al, 2016; Mayordomo-Febrer et al, 2017). However, alpha-2 agonists are associated with cardiovascular and respiratory effects that limit their use in older or clinically sick patients (Sinclair, 2003), and benzodiazepines can cause disinhibition, reduced & variable sedation, and undesirable recovery characteristics in healthy animals (Micieli et al., 2019; Murdock et al., 2020). For further information please see Perspectives on Premeds - Alpha-2 Agonists.

It should be remembered that although butorphanol has minimal cardiovascular and respiratory effects at clinical doses, it is a relatively poor and short-lived analgesic.  Therefore, if the patient is experiencing, or is anticipated to experience, pain the butorphanol should be substituted with buprenorphine (mild to moderate pain) or methadone (moderate to severe pain).

THE AIMS OF INTRAMUSCULAR ALFAXALONE SEDATION

Although alfaxalone is rapidly and effectively absorbed and produces reliable sedation, the reasons for selecting the intramuscular route should be considered, and the advantages weighed against the disadvantages.  Some examples of reasons for IM administration of alfaxalone in dogs include: the sedation of a difficult patient to reduce stress and facilitate handling prior to placement of an IV cannula and the administration of additional drugs; to perform diagnostic or minor procedures; for premedication prior to general anaesthesia; or to actually induce general anaesthesia.

As alfaxalone was originally designed as an induction agent it is recommended that following IM administration the patients is closely observed, and intubation, SpO2 monitoring equipment (pulse oximetry) and the ability to provide oxygen be available as a minimum even if general anaesthesia is not intended.

The following protocols, including doses, times to onset and duration, and any relevant clinical notes have been derived from the recent literature or personal experience. 

A handy wall chart summarising the IM alfaxalone protocols described below may be downloaded here.

Intramuscular alfaxalone in dogs. Protocols.

SUGGESTED INTRAMUSCULAR ALFAXALONE PROTOCOLS

1. SEDATION

For e.g. gaining IV access; diagnostic procedures, including echocardiography; or prior to induction of general anaesthesia.

The following information is based on recent literature and is not intended as an endorsement of specific protocols. The reader is advised to consult the full results described in each publication prior to selecting a combination.

1a. Alfaxalone 2mg/kg + butorphanol 0.4mg/kg + dexmedetomidine 0.005mg/kg (Murdock et al., 2020)

  • Moderate to deep sedation
  • Onset 5 minutes post injection. Peak from 10 minutes
  • Duration of sedation: up to 180 minutes. 4/6 dogs required atipamezole administration at 180 minutes
  • Loss of gag reflex and jaw tone in all dogs
  • PaO2 & PaCO2 remained within normal parameters
  • Decreased cardiac output and systemic vascular resistance from 10-30 and 5-30 minutes respectively. Considered to be related to dexmedetomidine
  • Smooth recoveries

1b. Alfaxalone 2mg/kg + butorphanol 0.4mg/kg + acepromazine 0.02mg/kg (Murdock et al., 2020)

  • Moderate to deep sedation
  • Onset 5 minutes post-injection. Peak from 10 minutes
  • Duration of sedation: up to 170 minutes
  • Loss of gag reflex in all dogs.  Jaw tone retained in some dogs
  • PaO2 & PaCO2 remained within normal parameters
  • Smooth recoveries

1c. Alfaxalone 1mg/kg + methadone 0.5mg/kg (Micieli et al., 2019)

  • Moderate to deep sedation
  • Onset <10 minutes
  • Duration of at least 25 minutes post administration (sedation not recorded beyond 25 minutes)
  • No clinically significant changes to heart rate, respiratory rate, or systolic arterial pressure in healthy adult dogs

2. IM ALFAXALONE FOLLOWING “INEFFECTIVE” PREMEDICATION OR SEDATION

For dogs that have not achieved the desired level of sedation following the administration of premedicant or sedative drugs, IM alfaxalone may be an option to increase the level of sedation and permit IV access

  • Alfaxalone 0.5mg/kg IM
  • Assess the quality of sedation after 10-15 minutes
  • Repeat the alfaxalone 0.5mg/kg if necessary

3. INTRAMUSCULAR ALFAXALONE FOLLOWED BY INDUCTION OF ANAESTHESIA WITH ALFAXALONE

If general anaesthesia is required, and the dog has not achieved stage III anaesthesia following the initial IM alfaxalone protocols described above, a further intravenous dose of alfaxalone may be administered slowly and to effect.

The dose of alfaxalone required to induce anaesthesia will be dependent on the existing degree of sedation:

  • Prepare 1-1.5mg/kg alfaxalone
  • Administer 0.5mg/kg of this dose intravenously
  • Flush the cannula with saline to ensure the 0.5mg/kg has been administered
  • Wait approximately 20 seconds
  • Assess depth of anaesthesia
  • Should the dog require additional alfaxalone the 0.5mg/kg incremental process may be repeated until intubation is possible or the full 1-1.5mg/kg dose has been administered

N.B. This dose of alfaxalone (1-1.5mg/kg) is lower than in the SPC for IV induction of anaesthesia in the dog. This is due to the dose sparing effect of the IM alfaxalone and the concomitant sedative agents on the subsequent IV induction dose of alfaxalone (Largos-Carvajal et al., 2020).

4. INTRAMUSCULAR ALFAXALONE FOR GENERAL ANAESTHESIA

Induction of general anaesthesia via the IM route should be carefully considered as sedation to permit IV cannulation then IV alfaxalone titrated to effect may be preferable. 

The following information is based on recent literature and is not intended as an endorsement of specific protocols. The reader is advised to consult the full results described in each publication prior to selecting a combination.

4a. Butorphanol 0.3mg/kg + medetomidine 0.005mg/kg.  15 minutes later alfaxalone 1-2.5mg/kg (Kato et al., 2021)

  • Time to intubation median 7.5-8 minutes (range 4-13) following alfaxalone administration
  • Duration of lateral recumbency median 89-105 minutes (range 61-130)
  • Spontaneous respiration maintained
  • ETCO2 remained within normal limits
  • No hypotension
  • Medetomidine induced bradycardia
  • Smooth recovery

4b. Alfaxalone 1.5mg/kg + butorphanol 0.1mg/kg + medetomidine 0.01mg/kg (Lee et al., 2016)

  • Deep sedation or reasonable quality general anaesthesia in healthy dogs
  • Smooth induction
  • Time to lateral recumbency 5.3 +/- 1.8 minutes
  • Duration of anaesthesia 89 +/- 17 minutes
  • No apnoea
  • ETCO2 remained within normal limits
  • No hypotension
  • Medetomidine induced bradycardia
  • Good recovery

4c. Alfaxalone 2.5mg/kg + butorphanol 0.25mg/kg + medetomidine 0.0025mg/kg (Tamura et al., 2016)

  • Smooth induction
  • Time to lateral recumbency 7 +/- 4.4 minutes. Peak at 10-30 minutes
  • Time to intubation 16 +/- 6 minutes
  • Duration of intubation 60 +/- 24 minutes
  • Duration of lateral recumbency 100 +/- 48 minutes
  • PaCO2 maintained within normal range
  • No clinically significant hypotension
  • Medetomidine induced bradycardia (<60bpm)
  • Smooth recovery

CONCLUSION

Alfaxalone administered via the intramuscular route provides rapid, dose-dependent sedation or general anaesthesia. Combining with (dex)medetomidine and an opioid will reduce dose requirements, and therefore injection volume, and will aid a smooth recovery.  For painful procedures butorphanol may be replaced with buprenorphine or methadone. 

The addition of other sedative agents will increase the duration of sedation and, dependent on drug(s) and doses used, may induce general anaesthesia. 

Alfaxalone may be used IM to additionally sedate dogs that have not responded as desired to other sedative/premedicant protocols.

OFF LICENCE & CASCADE ADVICE

It should be noted that the intramuscular administration of alfaxalone (Alfaxan® Multidose) is not currently authorised in the UK. The conditions for use are listed in the SPC (Summary of Product Characteristics) which may be accessed here (link to SPC). It is the responsibility of the veterinary surgeon accountable for the patient to assess clinical need & the suitability of the product and use it in accordance with the prescribing cascade.  Further details may be found at: https://www.gov.uk/guidance/the-cascade-prescribing-unauthorised-medicines   

Please download the Intramuscular Alfaxalone in Dogs wall chart here for a summary of the IM alfaxalone combinations and advice described in this article.

Article by
Matt Gurney
BVSc CertVA PgCertVBM DipECVAA FRCVS

Matt graduated from the University of Liverpool in 2003 and spent several years enjoying mixed practice before returning to Liverpool to undertake a residency in anaesthesia & analgesia. From 2009 to 2018 he developed and led the anaesthesia service at Northwest Veterinary Specialists, a multidisciplinary specialist hospital in Cheshire.

Matt is a European Veterinary Specialist and an RCVS Recognised Specialist and is President of the European College of Veterinary Anaesthesia & Analgesia. In 2020 he was awarded Fellowship of the Royal College of Veterinary Surgeons.  In October 2018 Matt returned to his roots in the south and joined Anderson Moores Veterinary Specialists where his main interests lie in acute and chronic pain management.

Anderson Moores Veterinary Specialists
Zero Pain Philosophy

Originally published: Wednesday, 17th March 2021
Last updated: Friday, 19th March 2021

References

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In this first of four parts discussing anaesthesia for the Caesarean section we examine the anaesthesia-relevant physiological changes that occur during pregnancy.

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Under Pressure: Practical blood pressure assessment and management.

The monitoring of blood pressure under anaesthesia is critical for patient care. In this article Claire Roberts, RVN and owner of SynergyCPD, examines the physiology, monitoring and management of blood pressure in anaesthetised patients.

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Cardiovascular stability with Alfaxan Multidose

Cardiovascular stability is a major feature of Alfaxan Multidose. In this article we examine the benefits for your patients and the supporting evidence.

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Paper summary: Effect of lingual swab placement on pulse oximetery readings

This study by Mair et al (2016) examined what effect the placement of swabs of different thicknesses and colour would have on pulse oximetry readings.

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Practical pulse oximetry for the Veterinary Nurse

Pulse oximetry is one of the most commonly performed monitoring procedures in veterinary anaesthesia. In this article Courtney Scales, RVN and owner of Anursethesia discusses the why and how we use pulse oximeters, the advantages and pitfalls, and how to manage abnormal readings.

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Paper summary: Comparison of direct and oscillometric blood pressure assessment using a veterinary specific device

Blood pressure management requires accurate monitoring. In this summary of an article by Acierna et al (2013) we compare a veterinary specific oscillometric device to direct blood pressure measurement.

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Having their best interests at HEART: Coronary collateral circulation in the rabbit, stress & the effects of alpha-2 agonists, phenothiazines and volatiles.

How extensive is the coronary collateral circulation in the rabbit and what are the effects of stress and drugs on the heart of this species?

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Co-induction of anaesthesia. Is there a clear advantage?

In this article Matt Gurney, RCVS/ECVS specialist in Veterinary Anaesthesia and Analgesia, examines whether co-induction techniques are advantageous.

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What are the benefits of slow administration of alfaxalone and does co-induction with alfaxalone/midazolam have any benefits in healthy dogs?

In this summary of a study by Miller et al (2019) we examine if there are any benefits to an alfaxalone/midazolam induction over alfaxalone alone in the healthy dog.

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Peri-anaesthetic management of the gastric dilation and volvulus (GDV) patient

In this article Carl Bradbrook discusses the peri-ananesthetic management of the canine gastric dilatation and volvulus (GDV) patient.

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Paper summary: Clinical efficacy and cardiorespiratory effects of alfaxalone, or diazepam/fentanyl for induction of anaesthesia in dogs that are a poor anaesthetic risk.

In this summary of a paper by Psatha et al (2011) we examine the clinical benefits of alfaxalone in high-risk patients when compared to the induction protocol of diazepam + fentanyl.

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Getting to the HEART of the matter - considerations for anaesthetising the cardiac patient.

In this article Miranda discusses the challenges of anaesthetising patients with cardiac disease and how protocols can be modified to accommodate these patients.

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Paper summary: How does buprenorphine compare to butorphanol for postoperative analgesia in cats?

A prospective multi-centre clinical trial comparing buprenorphine vs butorphanol for postoperative analgesia in cats.

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Paper summary: Analgesic effects of maxillary and inferior alveolar nerve blocks in cats undergoing dental extractions.

With dental surgery one of the most commonly performed procedures in small animal practice, what benefits do dental nerve blocks provide in cats?

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What should we consider when anaesthetising patients, including geriatrics, for dental procedures?

What should we consider when anaesthetising both adult and senior patients admitted for dental treatment?

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Checklist for geriatric dental anaesthesia

This article summarises and combines "Anaesthesia for the geriatric patient" and "What should we consider when anaesthetising patients, including geriatrics, for dental procedures?" into a single checklist for anaesthesia for the geriatric dental patient. A downloadable summary is also available by following the link.

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How do we recognise, assess and treat chronic pain in companion animals?

In this article Ian Self, Associate Professor in Veterinary Anaesthesia and Analgesia, School of Veterinary Medicine and Science, Nottingham, reflects on the recognition, assessment and management options for chronic pain in companion animals

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The physiology of acute and chronic pain.

In this article, which accompanies " How do we recognise, assess and treat chronic pain in companion animals?", Ian Self describes the physiology of acute and chronic pain

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What should we consider when anaesthetising the geriatric patient?

With an increasing number of anaesthetics being performed in older pets is there anything we should be aware of or do differently? In this article Carl Bradbrook examines the management of anaesthesia in geriatrics..

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Paper summary: What effect does does rapid, high volume fluid therapy have on cardiovascular function?

In this summary of a paper by Valverde (2012) we examine the effects of high-volume, rapid fluid therapy on cardiovascular function and hematological values during isoflurane-induced hypotension in healthy dogs.

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Paper summary: Pre-anaesthetic screening of geriatric dogs

In this summary of a paper by Joubert (2007) we examine the value of pre-anaesthetic screening in geriatric dogs and how the results influence the anaesthetic process.

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Anaesthesia for Canine Cushing's disease: What should we assess and what should we monitor?

Cushing's disease (hyperadrenocorticism) is relatively common in the dog and this article discusses the appropriate pre-anaesthetic assessment we should perform and why careful monitoring is essential.

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Paper summary: How frequently are intravenous catheters removed as a result of complications due to bacterial contamination?

In this summary of a paper by Ramos (2018) we examine the incidence of bacterial colonisation of intravenous catheters removed as a result of cannula complication

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What's the Point? Peripheral Intravenous Cannulation.

Peripheral venous cannulation is a common invasive procedure in small animals, but what are the best-practice insertion techniques and what can we do to avoid complications?

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Rabbit Anaesthesia – Understanding Your Patient.

How does the anatomy, physiology, behaviour and response to drugs affect your decision making when anaesthetising the rabbit patient?

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Paper summary: Heated intravenous fluids alone fail to prevent hypothermia in cats under general anaesthesia.

In this summary of a paper by Jourdan et al (2017) we examine the common practice of warming intravenous fluids and the effect on patient temperature.

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​Considerations for anaesthesia of the brachycephalic dog.

In this article Matt Gurney discusses the induction of anaesthesia and intubation of the brachycephalic patient.

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Watch the induction and intubation of a brachycephalic.

Induction of anaesthesia and intubation of a brachycephalic dog with Matt Gurney.

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Paper summary: The effect of omeprazole on oesophageal pH in dogs during anaesthesia

This summary of a publication by Panti et al., examines the effect of orally administered omeprazole on gastro-oesophageal reflux in the anaesthetised dog.

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How does a syringe driver benefit your patients?

Syringe drivers are becoming increasingly commonplace in modern veterinary practice and are a useful tool for multiple applications. This article looks at the science behind constant rate infusions and the basics of syringe driver use.

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Paper summary: Pet owner opinions about anaesthesia, pain and surgery in small animals

In this paper we explore perceptions and opinions of Canadian pet owners about anaesthesia, pain and surgery in small animals.

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Achieving Safer Anaesthesia with ASA and Joanne Michou MA VetMB DipECVAA MRCVS

How can a Veterinary version of the ASA Physical Status Classification help you achieve safer anaesthesia? To find out how watch our webinar.

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Paper summary: ASA classification and risk of anaesthetic related death in dogs and cats.

This scientific paper assessed whether the American Society of Anesthesiologists (ASA) Physical Status Classification correlated with the risk of anaesthetic death in dogs and cats.

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New! Methadyne, Our New Methadone Now Available

This is our third product launch this year, and the latest addition to our anaesthesia and analgesia portfolio, Methadyne, contains 10mg/ml methadone as its active ingredient. It can be administered for analgesia of moderate to severe pain in dogs and cats, to provide neuroleptanalgesia, and as part of a patient’s premedication protocol prior to general anaesthesia.

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A retrospective comparison of two analgesic strategies after uncomplicated tibial plateau levelling osteotomy in dogs.

In this review we summarise a publication by Bini (2018) examining two protocols for the administration of methadone following TPLO surgery in dogs.

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Practical Acute Pain Assessment

In this summary of acute pain assessment, Carl Bradbrook examines why we should be monitoring patients for pain and looks at the commonly used scoring systems.

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Alfaxan for the maintenance of anaesthesia: Peer reviewed clinical papers.

In this article we have identified the key clinical peer reviewed papers to support the use of Alfaxan for maintenance of Anaesthesia in Cats and Dogs.

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TIVA or not? (Total intravenous anaesthesia).

In this article the Jurox UK Technical Team discuss the use of intravenous agents to maintain anaesthesia in the dog and cat.

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Benzodiazepines - can they help reduce anaesthesia related side effects?

In part 4 of this series on premedicant agents we examine the pros and cons of benzodiazepines.

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Paper summary: Effect of benzodiazepines on the dose of alfaxalone needed for endotracheal intubation in healthy dogs

This paper examined whether a benzodiazepine, administered as a co-induction agent with alfaxalone, improved endotracheal intubation, and reduced the dose of alfaxalone, in the dog

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Putting methadone in its place in your pain management.

In this article we examine why methadone could be considered the analgesic of choice for many of our patients and understand its importance in modern veterinary medicine. The article includes a link to a downloadable summary sheet.

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Food for Thought: Pre-anaesthetic Fasting

In this article Karen examines why we fast our canine and feline patients prior to anaesthesia and what the current recommendations are. Karen also investigates why rabbits are different and should not be starved before anaesthesia.

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​Purr-fecting Pain Management

In this article summary we examine which of the two opioids, buprenorphine or butorphanol, provides the most appropriate analgesia following ovariohysterectomy in the cat.

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Perspectives on Premeds - Phenothiazines: from Mental Health to Premedication

In this article from the Perspectives on Premeds series, Karen takes us through the properties and uses of phenothiazines in modern veterinary practice.

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Methadone with Acepromazine - when is enough, enough?

This study looks at the effects of three methadone doses combined with acepromazine on sedation and some cardiopulmonary variables in dogs.

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AceSedate®, Our New Acepromazine, Available Now.

We have extended our anaesthesia and analgesia portfolio with the launch of AceSedate®. Containing the tried and trusted, long-acting sedative agent acepromazine as its active ingredient, AceSedate can be used for the premedication, sedation and tranquilisation of cats and dogs.

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Time: is 30 minutes long enough?

This recent study examined whether the application of EMLA cream, for 30 or 60 minutes, would be a useful tool to improve patient compliance prior to intravenous cannula placement in the veterinary clinical practice setting.

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Caesarean Section Survival Guide. Part 2: Anaesthetic Protocol Selection & Peri-operative Considerations.

In this second instalment of the 2-part article, we explore premedication, induction, maintenance & monitoring, recovery and analgesia for the Caesarean section patient.

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Buprenorphine: it’s not all static in rabbits

Opioids are well known for causing gastrointestinal stasis in mammalian species. This recent paper examined the effects of a single high dose of buprenorphine on the rabbit gastrointestinal tract using non-invasive imaging techniques.

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Caesarean Section Survival Guide. Part 1: Physiology & Pre-anaesthetic Considerations.

In the first instalment of this 2-part review Karen examines the physiological changes that occur during pregnancy and how those adjustments can affect the selection of anaesthetic protocols for the increasingly common Caesarean section.

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No leeway for the spay: A comparison between methadone and buprenorphine for perioperative analgesia in dogs undergoing ovariohysterectomy.

This recent paper compares post-operative pain scores and requirement for rescue analgesia following premedication with methadone or buprenorphine, in combination with acepromazine or medetomidine, in 80 bitches undergoing ovariohysterectomy.

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Cardiac arrest - the human factor

Cardiac arrest in dogs and cats is, thankfully, relatively rare. However, when it does happen it can have devastating consequences for the animal, owner and the veterinary team. This study examined the common causalities leading up to a cardiac arrest with the aim of changing protocols to improve outcomes.

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Are you Using Safety Checklists in your Practice?

In this article, Carl focuses on the benefits of introducing a safety checklist in practice to reduce patient morbidity, mortality and to improve communication between members of the veterinary team. The article contains links to the AVA safety checklist as well as a link to a customisable list that you can adapt to your practice needs. 

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The Big Chill - Temperature Management in Sedated and Anaesthetised Patients

The effects of hypothermia are very far reaching throughout the peri-anaesthetic process. In this article, James takes us through the interesting mechanisms of body cooling and warming, the clinical relevance of hypothermia and what we can do to prevent it.

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Keeping the Finger on the Pulse -  Nuances in CV Monitoring

All patients are exposed to the risks associated with general anaesthesia. Continuously monitoring anaesthetised patients maximises patients safety and wellbeing. In this article, Dan takes us through the common monitoring techniques that provide information about the cardiovascular status of your patient. 

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Effect of Maropitant on Isoflurane Requirements & Postoperative Nausea & Vomiting

Despite being widely recognized in humans, postoperative nausea and vomiting (PONV), and the role of maropitant in reducing inhalational anaesthetic requirements have been poorly documented in dogs. This recent study evaluates PONV and isoflurane requirements after maropitant administration during routine ovariectomy in bitches.

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New! Alfaxan® Multidose Now Available

We are happy to announce we have enhanced our anaesthesia and analgesia portfolio with the introduction of Alfaxan®Multidose for dogs, cats and pet rabbits.

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Sevoflurane requirement in dogs premedicated with medetomidine and butorphanol

Little information is available about the effect that different doses of medetomidine and butorphanol may have when using sevoflurane for maintenance of anaesthesia in dogs. This recent study evaluates heart rate and median sevoflurane concentration required at different dose rates.

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Capnography II - What happened to the elephants? A summary of abnormal traces

In this second article of the capnography series, James provides a guide to a few of the most common traces that you will encounter during surgery. Scroll to the end of the article to download a printable capnography cheatsheet. 

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Pain, what a Pain! (Part 2) – Practical Tips On How To Perform Dental Nerve Blocks In Companion Animal Practice

In this second article of the Pain, what a Pain! series, Dan takes us through the LRA techniques associated with dental and oral surgery. In this article, you will find practical tips and pictures on common dental nerve blocks as well as safety concerns to consider.

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​Peri-anaesthetic mortality and nonfatal gastrointestinal complications in pet rabbits

This recent retrospective study looks at the cases of 185 pet rabbits admitted for sedation or general anaesthetic and evaluates the incidence and risk factors contributing to peri-anaesthetic mortality and gastrointestinal complications.

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Pain, what a Pain! How Locoregional Anaesthesia can Improve the Outcome and Welfare of Veterinary Patients (Part 1)

In this first article out of a series of two, Dan takes us through an introduction and practical tips for appropriate local anaesthesia delivery. Find out why these anaesthesia techniques, that are well recognised in human medicine, have seen an increase in popularity in veterinary medicine over the recent years

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Perspectives on Premeds – Opioids

Perspectives on Premeds is a series of articles touching on different pharmacological, physiological and clinical aspects of pre-anaesthetic medication. This second article aims to provide a refresher on opioids.

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Effects of Dexmedetomidine with Different Opioid Combinations in Dogs

Read the highlights of a recently published research paper that evaluates cardiorespiratory, sedative and antinociceptive effects of dexmedetomidine alone and in combination with morphine, methadone, meperidine, butorphanol, nalbuphine and tramadol. 

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Preoxygenation Study Highlights

This study evaluates the effectiveness of two methods of preoxygenation in healthy yet sedated dogs and the impact of these methods on time taken to reach a predetermined haemoglobin desaturation point (haemoglobin saturation (SpO2) of 90%) during an experimentally induced period of apnoea.

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Capnography – Not Just a Load of Hot Air

Capnography is the measurement of inhaled and exhaled carbon dioxide (CO2) concentration. The graphical illustration of CO2 within respired gases versus times is known as the capnogram.

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Perspectives on Premeds – Alpha-2 Agonists

Perspectives on Premeds is a series of articles touching on different pharmacological, physiological and clinical aspects of pre-anaesthetic medication. This first article aims to provide a refresher on α2 agonists.

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Alfaxan - now licensed for use in pet rabbits

Jurox Animal Health is delighted to announce that Alfaxan is now licensed for cats, dogs and pet rabbits. This is an exciting advance and could change the way rabbits are anaesthetised in the U.K.

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