module 13 Abdominal emergencies Flashcards
Discuss the clinical findings in acute abdomen presentations
An acute abdomen may be associated with the following signs/history:
Vomiting/retching
Lethargy
Anorexia/hyporexia
Diarrhoea
Collapse
Poor perfusion parameters – pale MM, prolonged CRT, poor pulse quality
“Prayer position”
Bloating
Painful abdomen/back
Dysuria/Stranguria (less common)
Tachypnoea/tachycardia
Generalised abdominal tenderness
Presence of an abdominal mass or fluid wave
Specific pain focus within the abdomen
Splinting of the abdomen preventing effective palpation
NB. Spinal/back pain and orchitis/testicular torsion can present with similar clinical signs, hence a thorough palpation/manipulation of spine and testicles (if present) should also be performed
Depending on the cause, there may be concurrent clinical signs of:
shock/hypovolaemia
cardiovascular abnormalities
respiratory distress
neurological deterioration
In very ill/obtunded patients, signs of abdominal pain may not be apparent until end point resuscitation points are met (previously covered in Fluid module).
An effective abdominal palpation should allow you to comment on the size, position and pain response of the following organs and areas: Cranial abdomen, spleen, kidneys, bladder, and small intestines.
The following organs should be palpable if enlarged or full of ingesta: Colon, liver margins, prostate, and/or uterus (when gravid, less often when fluid filled).
The stomachs of patients presenting with GDV, can be easily detected by performing percussion due to its tympanic nature.
The general causes of abdominal pain include distention of a hollow viscus or organ capsule, ischaemia, neoplasia, traction and inflammation secondary to a variety of causes.
Describe the diagnostic workup for an acute abdomen presentation
Primary goal is to rapidly establish if surgical intervention is required. Perform blood gas, cbc, biochem, electrolytes, lactate,ecg, aptt/pt,bp, AFAST, complete abdo u/s, palpation, xrays, u/s guided abdominocentesis or blind abdominocentesis as indicated.;
US AREAS TO CHECK
Look for free fluid in the areas associated with fluid accumulation using AFAST technique:
Diaphragmatico-hepatic (DH) view
Splen-orenal (SR) view
Cysto-colic (CC) view
Hepato-renal (HR) view
Look for obvious mass lesions in the liver and spleen and examine the gallbladder
Use colour Doppler over the spleen to check blood flow (in cases of splenic torsion this will be reduced)
Examine prostate for abscessation/abnormalities
Fluid dilation of small intestines and stomach, especially if drop out associated caudal to dilation (may be foreign body – care to differentiate from faeces)
Look for changes to the intestinal wall layering and structures
Visualise the bladder, kidneys and the retroperitoneum
Examine the pancreatic region and ensure you have covered both the gastric and duodenal limbs
If free fluid is found, proceed abdominocentesis
XRAYS TO LOOK FOR;
Loss of serosal detail – note this is less sensitive than ultrasound for the detection of free abdominal fluid
Gastric dilation and volvulus
Presence or absence of a bladder outline
Fluid or gas distension of a hollow viscous
Dogs: ratio of largest small intestinal diameter to the height of a lumbar vertebral body on lateral radiograph of 1.5-2.0, is suggestive of small intestinal obstruction
Cats: ratio of largest small intestinal diameter to the height of lumbar vertebral body of 2.0-2.5, is suggestive of small intestinal obstruction
Plicated intestines (may not become distended) is suggestive of linear foreign body
Two populations of small intestines
Free air in the abdomen – if present without recent (<7 days) surgery is an indication for immediate laparotomy as this commonly indicates gastrointestinal rupture or abscessation.
PERITONEAL EFFUSIONS;
evaluate using refractometer (sg/protein) and automated cell count machine, and microscopy-direct smear for exudates and spin down and concentrate for transudates.
a)Transudate – Protein ≤25g/l with low cell count (fewer than 500 cells/ul).
The most common cause is hypoalbuminaemia. Portal vein occlusion is a
potential cause, but these cases usually result in a modified transudate. These
cases never require emergency exploratory laparotomy.
b)Modified transudate – Protein between 25 – 50g/l with moderate cell count
(300-5500 cell/ul). Most common causes include neoplasia, liver disease, and
right-sided heart failure. Modified transudate is the ‘least specific’ form of
effusion. There are many and varied causes of this fluid and further imaging is
often required to establish a diagnosis. Some of these patients require emergency
surgery.
c)Exudate – Protein ≥ 30g/l with high cell count (5000-7000 cells/ul). This is the
most common type of free fluid associated with acute abdominal pain. This fluid is
categorised into either septic or non-septic and can be challenging to determine.
o Definitive diagnosis of a septic exudate is the presence of intracellular and
extracellular bacteria.
o Comparing glucose and lactate levels of the abdominal effusion with peripheral
blood can be a useful indicator that the abdominal fluid is septic in cases where
intracellular bacteria cannot be visualised. The fluid is likely septic when the
glucose level is lower in abdominal fluid (>2mmol/l difference) and the lactate
level is higher (>2mmol/l). Typically there is a massive difference in septic
abdominal fluid, with glucose below the analyser scale (Low) and lactate
>10mmol/l.
o Patients with a septic abdominal effusion almost always require emergency
exploratory surgery.
Describe treatment for an acute abdomen presentation
Fluids-as per bolus for shock etc, later maintenance and ongoing losses. Most commonly reach for Hartmann’s first.
Pain relief usually reach for Opioids (pure Mu agonists) are the drugs of choice for severe abdominal pain
* Methadone, fentanyl, morphine
* Ketamine – NMDA receptors and help prevent wind up (often set up as a
CRI following initial opioid use if still very painful)
Discuss Acute Pancreatitis, including clinical signs, diagnostic plan and management
Acute pancreatitis involves increased/premature release of trypsinogen which becomes trypsin which triggers other pancreatic enzymes. There is no one specifc cause but predisposing/contributory factors include abdominal trauma, high fatty meal, elevated calcium, phenobarbitone, trimethsulpha, potassium bromide, hypertriglyceridaemia (esp miniature schnauzer) or other lipid metabolism disorders. In cats often associated with inflammatory bowel disease and /or cholangeitis (triaditis).
The inflammation may progress to Systemic Inflammatory Response Syndrome Sirs) or Multi Organ Dysnfunction Syndrome (MODS) or dic.
In dogs, approximately 90% of patients present with anorexia and vomiting. 50% have
abdominal pain, and approximately 30% have diarrhoea.
* With cats, approximately one third of cases present with vomiting and only 25% with
abdominal pain. They more commonly present with just anorexia and lethargy.
Spec cpl/fpl is highly sensitive but not very specific (likely positive for any cranial abdo problem).
U/s ideal.
Most respond within few days to pain relief , anti-emetics and fluids.
Use opiods. Avoid metacam. Can use gaba for milder forms.
ONLY use ab’s if infectious cause found.
Emergency surgery rarely required but IS required for
extra-hepatic biliary obstruction which is NOT responding to medical management (weeks)or pancreatic abscessation. need specialist surgeon.
encourage low fat eating asap.
Discuss Acute Gastroenteritis, including clinical signs, diagnostic plan and management
Acute gastroeneteritis is non specific and ddx parasites, virus, toxin, bacterial, fb, inappropriate food ingestion etc.
ACUTE HAEMORRHAGIC DIARRHOEA SYNDROME (AHDS) previously known as HGE IS A SPECIFIC life threatening condition which does not have 1 specific cause but is theorised to be an abnormal immune response to bacteria/bacterial endotoxins or certain food components. In this syndrome there is usually significant haemoconcentration yet with near normal total protein. Tx is supportive and specific.
eg.Hookworm, Roundworm, Whipworm:
o Fenbendazole 50mg/kg PO SID for 3 days
* Giardia:
o Fenbendazole 50mg/kg PO SID for 7 days
o Can be combined with metronidazole 20mg/kg PO Q12 (note: this dose can
result in vestibular signs)
* Coccidiosis:
o Toltrazuril 20mg/kg PO SID for 2-3 days
Premature use of antibiotics can have adverse effects such as disturbing the
healthy gastrointestinal microbiome, and promoting antibiotic resistance
* In cases of severe or protracted gastroenteritis/AHDS, antibiotics can be introduced
with metronidazole at 10mg/kg IV Q12 or Amoxicillin-clavulanic acid at 12.5mg/kg
SC Q24, transitioning to oral formulations when appropriate
* In cases where there are signs consistent with sepsis, broad spectrum intravenous
antibiotic therapy is indicated.
The diagnostic approach is aimed at identifiing specific ddx’s and treating appropriately.
Investigations:
Faecal float-often overlooked. DO IT. May diagnose coccidia, hookworm and or roundworm. Do on all esp less than 6months with no worm tx and esp if non regenerative anaeamia.
Bloods
viral testing
imaging
giardia snap-giarrdia is relatively common so DO IT.
Discuss Gastric Dilation and Volvulus (GDV), including clinical signs and diagnostic plan and management
Gastric dilation and gastric volvulus usually occur together (with volvulus occurring later) but they can occur separately and rarely, torsion can occur without dilation.
Volvulus can be partial to completely 360 degrees (most commonly 180 degrees) The usual direction of torsion is clockwise, with the usual right sided pylorus moving to left and ventrally,but 5% are anticlockwise and these usually associated with a prior underlying pyloric outflow obstruction.
CLINICAL SIGNS;
tympanic stomach,
drooling,
shock
prolonged crt
regurg/v+
PLAN/MANAGEMENT
shock fluids,pain relief, single lateral right xray if in doubt, check coags, electrolytes and lacate,attempt stomach tube/trochar stomach, surgery to decompress, de-rotate,clear necrosis (splenectomy, partial gastrectomy), pexy.
List the post-operative management and monitoring of GDV patients
Fluid therapy
o Rate and crystalloid type based on patient assessment and repeat blood gas
(typically 3-10ml/kg/hr)
o Higher fluid rates may be required due to fluid third spacing into the
peritoneum or gastrointestinal tract (likely a result of inflammation and
hypoproteinaemia)
* Analgesia
o Fentanyl CRI @ 2-5ug/kg/hr. Attempt to wean first due to complications
with GIT status
o Lignocaine IV bolus of 2mg/kg, then CRI at 1-3mg/kg/hr or 20-50mcg/kg/min over first 24hrs post-surgery at least. It may cause sedation
and nausea
* Prokinetics
o Metoclopramide CRI 1-2mg/kg/day
* Anti-emetics
o Maropitant 1mg/kg IV, SC q24hrs – maximum dose of 5 days. *Note: stings
when given subcutaneously
* Diagnostic tests
o Coagulation Screening @ 12-24hrs post-operatively due to risk of DIC
o Biochemistry @ 24hrs post-operatively if concerned about the risk of MODS
o PCV/TS to monitor for haemorrhaging/bleeding
o Electrolytes/blood gas and ACT q4-8hrs within first 12-24hrs, then extend to
q12-24hrs if improving. Hypokalaemia potentiates ileus, gastroparesis, and
cardiac arrhythmias if not treated.
* Continuous ECG monitoring as arrhythmias are a common occurrence,
especially ventricular premature complexes (VPCs)
* Nutrition
o Lectade @ 1mL/kg CRI through NG tube for 12 hours then switch to Ensure
or Pediasure if anorexic at 1/3 RER
o If tolerating well, increase by 1/3 every 8-12hrs
Lactate prognostic indicators is used as an indicator of survival and not gastric necrosis.
Failure to reduce level is correlated with increased mortality.
o Reduce by >42% within 80-100mins has improved survival rate
o Reduced to <6.4mmol/L or by >4mmol/L units has an improved survival rate
o >9mmol/L on presentation is associated with a poorer prognosis
* Previous splenectomy is not associated with increased risk of developing GDV
* Evidence of cardiomegaly (on right lateral radiograph at initial diagnosis) is associated
with a significantly worse prognosis.
Recurrence rates for GDV following initial gastropexy is <5%
* Partial gastrectomy combined with splenectomy, hypotension, peritonitis, sepsis and
DIC worsen prognosis
* Clinical signs existing for >6hrs prior to presentation are more prone to having partial
gastrectomy, splenectomy or cardiac arrhythmias making their prognosis worse
Discuss Acute Non-Traumatic Haemoabdomen - including clinical signs and diagnostic plan and management
In dogs this is 80% due to neoplasia, and most of those are splenic (and 50-60% of those are malignant with 3 month survival expectancy).. Less than 50% are neoplastic in cat. ddx coagulopathy, neoplasia, sepsis, splenic torsion etc.
Rule out coagulopathy , stabilise with fluids and pain relief, afast, in depth u/s, chest rads for mets if indicated, ex lap.
