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Letters
RABBIT HEALTH
Treatment of gastric dilatation in rabbits I READ with interest the paper by Schuhmann and Cope, entitled ‘Medical treatment of 145 cases of gastric dilatation in rabbits’ (Schuhmann and Cope 2014). This paper highlights the dilemma that practitioners face when presented with an acutely anorexic rabbit with an enlarged stomach and I would like to make some comments on the subject. In rabbits, intestinal obstruction by a pellet of compressed hair is the most likely cause of gastric dilation and many of these cases will resolve without surgery because the pellet can pass through to the hindgut (Harcourt-Brown 2007). Any supportive treatment can aid this process and the protocol that Schuhmann and Cope describe is an example. However, if the pellet does not pass through to the hindgut, the small intestine will remain obstructed and the rabbit will die (Harcourt-Brown 2013). Its death will be a painful one. Rupture of the stomach or small intestine and peritonitis are just some of the possible consequences of gastric tympany. The dilemma that practitioners face is to know which rabbits need surgery to relieve the obstruction and which rabbits will respond to supportive care. Unfortunately, the paper by Schuhmann and Cope does not really help with this dilemma. Surgical cases were excluded from the study and case selection is not described. The authors describe a ‘one size fits all’ protocol of metoclopramide, subcutaneous fluids and metamizole followed by syringe feeding, as if it is a magic bullet that will cure most cases of gastric dilation. My concern is that practitioners might use this combination without assessing the patient properly so some rabbits will die a painful death.
There is also a problem with the use of metamizole. As a sole ingredient, the product was withdrawn in the UK because of safety concerns with its use in people, although it is still available in combination with butylscopolamine (Buscopan Compositum; Boehringer Ingelheim) to treat spasmodic colic in horses and diarrhoea in dogs. It would be good to have clarification from the authors about the use of this product in the treatment of gastric dilation in rabbits. In my opinion, the exact details of the medical products that are used are not the prime reasons for success or failure in the treatment of rabbits with an intestinal foreign body. Pellets of compressed hair can move, so gut motility, time, luck and pellet size also play a part in whether a pellet will pass through the small intestine. Supportive care with medical treatment can assist the process but does not guarantee it and the need for different types of treatment varies between patients. The protocol that Schuhmann and Cope describe would not be suitable for every case. There is a difference between a rabbit with gastric distension and gastric tympany. In my
opinion, rabbits with gastric tympany are shocked and need fluids intravenously rather than subcutaneously. An opioid should be included in the analgesic protocol. Decompression of the stomach by passing a stomach tube is beneficial, although not always possible. Sedation for radiography and other procedures could be required and, on humane grounds, surgery must be considered for rabbits that are not responding to treatment. In most cases, surgery is not difficult and is diagnostic, and those cases that have a tumour or inoperable adhesion can be euthanased to relieve further suffering. In cases where an intestinal foreign body is found, the success rate is greater if the surgery is performed before the rabbit is too shocked. Yes, it is probable that the foreign body could have passed through on its own in some of these rabbits but at least the situation is resolved. An analogy with an animal giving birth can be made. The decision when to perform a caesarean is always a difficult one. Surgery is time consuming, expensive and perhaps unnecessary. Conversely, no surgery can result in suffering and death. Abdominal radiography is very helpful
August 9, 2014 | Veterinary Record | 153
Downloaded from http://veterinaryrecord.bmj.com/ on June 26, 2015 - Published by group.bmj.com
Letters in monitoring rabbits with an intestinal foreign body because gas acts as a good contrast medium. Radiography can easily be repeated to monitor the progress of patients and a key feature is the presence of gas in the hindgut, which indicates that the foreign body has passed through the ileocolic valve to release gas and fluid into the caecum and colon. These patients will not need surgery. The caecum and colon can be recognised on abdominal radiographs by their shape and size. They are much wider than the small intestine. Blood glucose monitoring is another useful aid because values rise with the severity of the rabbit’s condition (HarcourtBrown and Harcourt-Brown 2012). Blood glucose is cheap and easy to measure and a rise or fall in levels can help with decision making. As a rule of thumb, values below 10 mmol/l are reassuring, values between 10 and 15 mmol/l indicate that the patient should be closely monitored, values between 15 and 20 mmol/l are cause for concern and effective analgesia is a priority and values above 20 mmol/l indicate that the rabbit’s condition is serious and that surgery might be the only way to save its life. Administration of any fluids that contain glucose will interfere with the validity of the result. A full description of intestinal obstruction and gastric dilation is given in the BSAVA Manual of Rabbit Surgery, Dentistry and Imaging (Harcourt-Brown 2013). A whole chapter is devoted to it. An approach to the acutely anorexic rabbit is described with the idea of aiding practitioners to differentiate between medical and surgical cases. Frances Harcourt-Brown, Crab Lane Veterinary Surgery, 30 Crab Lane, Bilton, Harrogate, North Yorkshire HG1 3BE e-mail: [email protected]
References
HARCOURT-BROWN, F. M. (2007) Gastric dilation and intestinal obstruction in 76 rabbits. Veterinary Record 161, 409-414 HARCOURT-BROWN, F. M. (2013) Gastric dilation and intestinal obstruction. In BSAVA Manual of Rabbit Surgery, Dentistry and Imaging. Eds F. M. Harcourt-Brown, J. Chitty. British Small Animal Veterinary Association. pp 172-189 HARCOURT-BROWN, F. M. & HARCOURTBROWN, S. F. (2012) Clinical value of blood glucose measurement in pet rabbits. Veterinary Record doi:10.1136/vr.100321 SCHUHMANN, B. & COPE, I. (2014) Medical treatment of 145 cases of gastric dilatation in rabbits. Veterinary Record doi:10.1136/vr.102491
doi: 10.1136/vr.g5000
154 | Veterinary Record | August 9, 2014
Downloaded from http://veterinaryrecord.bmj.com/ on June 26, 2015 - Published by group.bmj.com
Treatment of gastric dilatation in rabbits Frances Harcourt-Brown Veterinary Record 2014 175: 153-154
doi: 10.1136/vr.g5000 Updated information and services can be found at: http://veterinaryrecord.bmj.com/content/175/6/153
These include:
References Email alerting service
This article cites 1 articles, 1 of which you can access for free at: http://veterinaryrecord.bmj.com/content/175/6/153#BIBL Receive free email alerts when new articles cite this article. Sign up in the box at the top right corner of the online article.
Notes
To request permissions go to: http://group.bmj.com/group/rights-licensing/permissions To order reprints go to: http://journals.bmj.com/cgi/reprintform To subscribe to BMJ go to: http://group.bmj.com/subscribe/
Letters
RABBIT HEALTH
Treatment of gastric dilatation in rabbits I READ with interest the paper by Schuhmann and Cope, entitled ‘Medical treatment of 145 cases of gastric dilatation in rabbits’ (Schuhmann and Cope 2014). This paper highlights the dilemma that practitioners face when presented with an acutely anorexic rabbit with an enlarged stomach and I would like to make some comments on the subject. In rabbits, intestinal obstruction by a pellet of compressed hair is the most likely cause of gastric dilation and many of these cases will resolve without surgery because the pellet can pass through to the hindgut (Harcourt-Brown 2007). Any supportive treatment can aid this process and the protocol that Schuhmann and Cope describe is an example. However, if the pellet does not pass through to the hindgut, the small intestine will remain obstructed and the rabbit will die (Harcourt-Brown 2013). Its death will be a painful one. Rupture of the stomach or small intestine and peritonitis are just some of the possible consequences of gastric tympany. The dilemma that practitioners face is to know which rabbits need surgery to relieve the obstruction and which rabbits will respond to supportive care. Unfortunately, the paper by Schuhmann and Cope does not really help with this dilemma. Surgical cases were excluded from the study and case selection is not described. The authors describe a ‘one size fits all’ protocol of metoclopramide, subcutaneous fluids and metamizole followed by syringe feeding, as if it is a magic bullet that will cure most cases of gastric dilation. My concern is that practitioners might use this combination without assessing the patient properly so some rabbits will die a painful death.
There is also a problem with the use of metamizole. As a sole ingredient, the product was withdrawn in the UK because of safety concerns with its use in people, although it is still available in combination with butylscopolamine (Buscopan Compositum; Boehringer Ingelheim) to treat spasmodic colic in horses and diarrhoea in dogs. It would be good to have clarification from the authors about the use of this product in the treatment of gastric dilation in rabbits. In my opinion, the exact details of the medical products that are used are not the prime reasons for success or failure in the treatment of rabbits with an intestinal foreign body. Pellets of compressed hair can move, so gut motility, time, luck and pellet size also play a part in whether a pellet will pass through the small intestine. Supportive care with medical treatment can assist the process but does not guarantee it and the need for different types of treatment varies between patients. The protocol that Schuhmann and Cope describe would not be suitable for every case. There is a difference between a rabbit with gastric distension and gastric tympany. In my
opinion, rabbits with gastric tympany are shocked and need fluids intravenously rather than subcutaneously. An opioid should be included in the analgesic protocol. Decompression of the stomach by passing a stomach tube is beneficial, although not always possible. Sedation for radiography and other procedures could be required and, on humane grounds, surgery must be considered for rabbits that are not responding to treatment. In most cases, surgery is not difficult and is diagnostic, and those cases that have a tumour or inoperable adhesion can be euthanased to relieve further suffering. In cases where an intestinal foreign body is found, the success rate is greater if the surgery is performed before the rabbit is too shocked. Yes, it is probable that the foreign body could have passed through on its own in some of these rabbits but at least the situation is resolved. An analogy with an animal giving birth can be made. The decision when to perform a caesarean is always a difficult one. Surgery is time consuming, expensive and perhaps unnecessary. Conversely, no surgery can result in suffering and death. Abdominal radiography is very helpful
August 9, 2014 | Veterinary Record | 153
Downloaded from http://veterinaryrecord.bmj.com/ on June 26, 2015 - Published by group.bmj.com
Letters in monitoring rabbits with an intestinal foreign body because gas acts as a good contrast medium. Radiography can easily be repeated to monitor the progress of patients and a key feature is the presence of gas in the hindgut, which indicates that the foreign body has passed through the ileocolic valve to release gas and fluid into the caecum and colon. These patients will not need surgery. The caecum and colon can be recognised on abdominal radiographs by their shape and size. They are much wider than the small intestine. Blood glucose monitoring is another useful aid because values rise with the severity of the rabbit’s condition (HarcourtBrown and Harcourt-Brown 2012). Blood glucose is cheap and easy to measure and a rise or fall in levels can help with decision making. As a rule of thumb, values below 10 mmol/l are reassuring, values between 10 and 15 mmol/l indicate that the patient should be closely monitored, values between 15 and 20 mmol/l are cause for concern and effective analgesia is a priority and values above 20 mmol/l indicate that the rabbit’s condition is serious and that surgery might be the only way to save its life. Administration of any fluids that contain glucose will interfere with the validity of the result. A full description of intestinal obstruction and gastric dilation is given in the BSAVA Manual of Rabbit Surgery, Dentistry and Imaging (Harcourt-Brown 2013). A whole chapter is devoted to it. An approach to the acutely anorexic rabbit is described with the idea of aiding practitioners to differentiate between medical and surgical cases. Frances Harcourt-Brown, Crab Lane Veterinary Surgery, 30 Crab Lane, Bilton, Harrogate, North Yorkshire HG1 3BE e-mail: [email protected]
References
HARCOURT-BROWN, F. M. (2007) Gastric dilation and intestinal obstruction in 76 rabbits. Veterinary Record 161, 409-414 HARCOURT-BROWN, F. M. (2013) Gastric dilation and intestinal obstruction. In BSAVA Manual of Rabbit Surgery, Dentistry and Imaging. Eds F. M. Harcourt-Brown, J. Chitty. British Small Animal Veterinary Association. pp 172-189 HARCOURT-BROWN, F. M. & HARCOURTBROWN, S. F. (2012) Clinical value of blood glucose measurement in pet rabbits. Veterinary Record doi:10.1136/vr.100321 SCHUHMANN, B. & COPE, I. (2014) Medical treatment of 145 cases of gastric dilatation in rabbits. Veterinary Record doi:10.1136/vr.102491
doi: 10.1136/vr.g5000
154 | Veterinary Record | August 9, 2014
Downloaded from http://veterinaryrecord.bmj.com/ on June 26, 2015 - Published by group.bmj.com
Treatment of gastric dilatation in rabbits Frances Harcourt-Brown Veterinary Record 2014 175: 153-154
doi: 10.1136/vr.g5000 Updated information and services can be found at: http://veterinaryrecord.bmj.com/content/175/6/153
These include:
References Email alerting service
This article cites 1 articles, 1 of which you can access for free at: http://veterinaryrecord.bmj.com/content/175/6/153#BIBL Receive free email alerts when new articles cite this article. Sign up in the box at the top right corner of the online article.
Notes
To request permissions go to: http://group.bmj.com/group/rights-licensing/permissions To order reprints go to: http://journals.bmj.com/cgi/reprintform To subscribe to BMJ go to: http://group.bmj.com/subscribe/
