DD of vomitus Flashcards
Vomiting vs regurgitation vs expectoration
Vomitng: expulsion of material from the stomach and/or intestines. Nausea, active contractions of abdomen
Regurgitation: expulsion of material from mouth, pharynx or oesophagus. Can be easily aspirated. Often eats the content.
Expectoration: expulsion of material from the respiratory tract
Distinguishing regurgitation from vomiting
- history: nausea, retching, eating the content
- physical exam: palpation of distended cervical oesophagus, cervical mass, injury or foreign body
- thoracic radiography: megaoesophagus, foreign body, perforation
- endoscopy: oesophagitis, hiatal hernia, stricture
- fluoroscopy: motility disorder, hiatal hernia, stricture
Physiology of vomiting
Activation of the emetic centre, which lies within the reticular formation of the medulla oblongata, can happen by various stimuli.
Humoral pathway: neurons of emetic centre can be activated by certain blood-borne toxins or drugs through activation of the chemoreceptor trigger zone (CTZ) that is located within the area postrema on the floor of the fourth ventricle.
Neural pathway: vagal and sympathetic neurons stimulated by receptors in the abdominal viscera and many other sites throughout the body can produce a vomiting reflex in the emetic centre. Receptor activation can occur as a result of inflammation, irritation, distensions or hypertonicity, among other factors.
Activation of the CRTZ is induced by a variety of humoral emetogenic substances (e.g., uraemic toxins, apomorphin, cardiac glycosides, cytotoxic agents). The reflex arch needs to be intact in order for animals to vomit as ablation of the area postrema abolishes emesis. Finally, impulses from the vestibular centre (inner ear) during motion sickness are thought to travel through the CRTZ to the vomiting centre.
Causes of vomiting
- diet
- emetogenic substances
- GIT obstruction
- GI inflammation/irritation
- extraalimentary tract diseases
- motion sickness
- CNS problems
- miscellaneous
More precise causes of vomiting
Acute vomiting. Causes
NON LIFE THREATENING:
- acute gastritis
- ascaris infection (puppies)
- Giardia
- motion sickness
POTENTIALLY LIFE THREATENING
- foreign body
- ulcer
- intususception
- parvo, distemper, infectious canine hepatitis
- leptospirosis
- AHDS (acute haemorrhagic diarrhea syndrome)
- GDV (gastric dilatation and volvulus)
- acute pancreatitis
- acute renal failure
- acute hepatic failure
- hypoadrenocorticism
- pyometra
- peritonitis
- sepsis
- DKA (diabetic ketoacidosis)
Chronic vomiting. Causes
- metabolic disease: renal disease, pancreatitis, hepatic disease, biliary disease, hypoadrenocorticism, hypercalcemia, feline hyperthyroidism, hypokalemia
- gastric disease: foreign body, mucosal hypertrophy, gastritis, neoplasia, hypomotility, enterogastric reflux, parasites
- SI disease: parasites, subileus, neoplasia
- neurologic disease: vestibular disease, autonomic epilepsy, neoplasia
Chronic vomiting. What to examine first?
- history and physical exam
- CBC and biochemistry
- urinalysis
- T4 (cats)
- cortisol (dogs)
- decal exam
- radiograph
After these we need to narrow the cause
- systemic/metabolic disease
- parasites
- mass/obstruction
- no specific findings
Physical examination of vomiting patient
- oral examination: uraemia, ulcers, icterus, CRT, foreign bodies (at the basis of the tongue)
- cassia arrhythmia: acid-base abnormalities, electrolyte imbalance/toxins
- abdominal palpation: pain (pancreatitis, obstruction), effusion (peritonitis), gas distension (GDV, ileus), abdominal mass (neoplasia, foreign body)
- rectal examination: melena, constipation
Lab evaluation of vomiting patient
- complete blood count: often optimal in primary gastric disease
- anemia
- neutropenia: parvo
- neutrophilic leukocytosis: acute pancreatitis, IBD, bacterial enterocolitis
- eosinophilia: parasites, hypoadrenocorticism
Radiography of vomiting patient
PLAIN RADIOGRAPHY
- foreign body
- gastric distension
- displacement, malposition
- delayed gastric patient (fasted animal still has fluid and ingests in stomach)
- penetrating gastric or intestinal ulcer (pneumoperitoneum)
CONTRAST RADIOGRAPHY
- foreign bodies, masses
- deep ulceration
- pylorus obstruction
- gastric motility disorder
USG in vomiting patient
- detection of dilated stomach with fluid (pylorus obstruction, motility disorder)
- thickened walls (chronic inflammation, neoplasia)
- state of abdominal organs
- ileus
Gastroduodenoscopy in vomiting patient
- most useful for gastric diseases
- direct visualisation, biopsy, histopath
Goal of treatment of vomiting patient
- treatment of underlying cause
- antiemetics therapy
- correction of electrolyte and acid-base imbalances, fluid therapy
- gastric mucosal protection, nutrition
- deworming
Antiemetics in vomiting patients
- maropitant-citrate (Cerenia) - inhibition of NK-1 receptor
- phenotiazines
- metoclopramide (not sufficient in cats)
- ondansetron
Fluid therapy in vomiting patient
- 0,9% saline infusion
- K supplementations are often needed
Vomiting is life-threatening or not? What to pay attention to?
Fever, melena, weakness, anorexia > 48h, abdominal pain, coffe-ground emesis or hematemesis, pale oral mucosa, abdominal swelling, obvious information (e.g. ingested toxins)
Antacids and protectants in vomiting patient
ANTACIDS:
- H2 antagonists: famotidine, ranitidine
- PPI: emeprazole, pantoprazole
PROTECTANTS:
- sucralfate: should not be given within 2h of other medications!
- misoprostol: not in pregnant patients
