Its not just the actual stomach wall that needs to remain hydrated but the entire GI tract. Otherwise ingesta in the intestines, caecum etc will dehydrate and become a potential risk for causing further obstruction I think :?
So if the bloat resolves and the stomach empties I guess the dehydrated ingesta further down will just cause more problems maybe :?
All I know is that in the more severe cases of Ileus/bloat I have seen the Rabbit has greatly benifitted from SQ or IV fluids.
SQs are no good if the Rabbit is in vascular shut down though as they wont be absorbed.
This is also how I understand the process. The stomach itself is not dried out but full of gas and mucus and distended when there is an accompanying bloat. However, not all bloats are secondary to impactions or obstructions and can manifest independently. The cause of these is largely unknown and they are acute and 'true bloat'.
However, when you have an obstruction/impaction or simply a rabbit manifesting ileus leading to full blown gastric stasis - you very often get an associated bloat but not always. I find it interesting that you can have stasis without bloat but not bloat without stasis - which always seems to accompany any bloat. To me this would indicate two separate processes that are largely symbiotic....and have a 'knock on' effect, but which are subject to a whole host of different and interdependent factors.
If the bloat resolves and the stomach empties into the lower GI tract, but the ingesta remains, there is nowhere for it to go....bunny is obstructed and the bloat reoccurs. Poppy's bloat certainly blew up and down over 2 days depending on where we were in the treatment regime. Once the ingesta is rehydrated sufficiently using fluids (a rabbit in systemic shock will need IV fluids as Jane says) you then need to move it out of the way....otherwise it can cause further problems...i.e. the impaction remains... and the stomach bloats up again as the 'primary cause' of the bloat if not an isolated bloat case has not been dealt with. Even if the cause is purely a non-obstructive stasis....restablishing normal gut function appears to be crucial as so many systems in the rabbit body appear to be highly dependent on this one mechanism. Horses and 'colic' to me bear much resemblance. Bunny tummies seem to be the epicentre of bunny health.
Whatever is the cause of the gastric 'interruption' if you like, be it bloat, obstruction, impaction, pain or stress related ileus, a chain of events has begun. The guts stop moving and can cause an acute bloat of gas in the stomach whatever the physiological causes behind this I suspect fermentation without adequately functioning systems to remove the gas produced, a distended abdomen puts pressure on both respiratory and cardiovascular systems, this in itself is critical. When the guts stop moving the highly colonised caecal flora which are dependent on gut motility also quickly get out of balance and you get an acute dysbiosis which has significant effect on further gut function as part of the feedback loop, and in particular on renal and liver function. If the kidneys can not function properly or bunny goes into acute renal failure then bunny can not maintain blood volume and then you are in trouble. One way to increase blood volume is to absorb fluid back out of the guts....the guts slow further and the mass dehydrates again. If renal output and blood volume can not be maintained bunny goes into systemic and cardiovascular shutdown.
Alongside these processes, stress hormones, catecholamines, released when bunny is in pain and shock both emotionally and systemically act on the autonomic nervous system which controls gut function....they slow it down further - the ingesta stays put. This is why I believe that when appropriate, and there is no risk of rupture, that moving the rehydrated mass along and out of the gut using a gut motility agent, and reestablishing normal gut function is essential to allow the associated bloat to subside and prevent all the other risk factors in the run away chain of events. Therefore to control stress hormone release which further precipitates the events....adequate pain relief is crucial.
It always appears to my inexperienced eyes that once gut function is back under control that this is when bunny starts to recover.
In summary....pain relief, fluids, shifting the gas - gripe water, anti-spasmodics as Jane has found (due to gut innervation which is all part of the feedback loop) and gut motility agents appear to be the way to treat these critical cases. It certainly has worked for both of my buns.
