Episode 9 - Bonus Episode! Acute Vomiting in Dogs and Cats

1.The GP hook

A brisk, practical read for UK vets and nurses on assessing and stabilising acutely vomiting dogs and cats, with real‑world tips from Brendan and Charlotte.

A brisk, practical guide for UK vets and nurses on assessing and stabilising acutely vomiting dogs and cats — real‑world tips from Brendan and Charlotte.

Acute vomiting is bread‑and‑butter GP work — and sometimes a trap. Triage fast, treat what matters first, and don’t miss the foreign body hiding in plain sight.

2.Vomiting vs regurgitation — get this right first

Why it matters: imaging choices, drug selection (prokinetics vs antiemetics, acid suppression) and management pathways differ between the two.

“Vomiting needs effort. Regurgitation doesn’t.”

If antiemetics don’t stop the episode, re‑consider regurgitation or obstruction.

• Vomiting: active abdominal contractions/retching, often noisy and prolonged and commonly smells acidic. Owners may report lip‑smacking and drooling beforehand.
• Regurgitation: passive, usually soon after eating, no abdominal effort; material looks/smells like undigested food. Think oesophageal disease (brachycephalics can make small “huffs” but still lack true retching).

3.The history that helps you win

Practical tip: prompt owners specifically — “Has anything gone missing? Any medicines out of reach?” — it often jogs memory.

• Fluid in vs fluid out: how many vomits, volume/consistency, ability to keep water down, diarrhoea (frequency and type).
• Blood: a few specks after repeated retching often points to gastritis; pools/clots or worsening blood over 24–48h is higher risk.
• Diet/scavenging: recent diet changes, scavenged items (socks, toys, period products, underwear), missing items in the house.
• Medications: current animal meds (esp. NSAIDs), and any accessible human meds.
• Pattern: first‑time acute vs recurrent or chronic enteropathy flaring.

4.First look, then hands‑on: exam priorities

Recheck the abdomen after initial stabilisation — a guarded, anxious patient may mask true pain.

• Demeanour is diagnostic: a dog wandering and sniffing is less likely to be in shock; a flat, non‑responsive cat is worrying.
• Shock vs dehydration:
• Shock (hypovolaemic): pale mucous membranes, prolonged CRT, weak pulses, poor perfusion. Dogs commonly tachycardic; cats can be bradycardic. Low temperature is a red flag.
• Dehydration: skin tenting, tacky mucous membranes, sunken eyes/third eyelid; replace after perfusion is restored.
• Respiratory: brachycephalics are aspiration risks — auscultate carefully.
• Neuro screen: altered mentation or ataxia changes your differential.
• Abdomen: interpret tenderness in context — nervousness can mimic pain. New, severe, out‑of‑character abdominal pain (yelp/snap on palpation) in a dog suggests septic abdomen and needs urgent imaging.

5.Stabilise before you investigate

Safety note on calculations and pumps: if you programme a pump for a bolus, double‑check the maths and local protocols before administration. Example from the discussion (for illustration only): a 10 kg dog receiving 10 ml/kg over 15 minutes = 100 ml total; that equals 100 ml in 15 minutes (400 ml/hr) with VTBI set to 100 ml. Confirm any such calculation and dosing against your local guidance and peer review before use.

Why bolus rapidly? You want to restore vascular volume and perfusion. Too slow and fluid may leak into tissues without improving circulation.

• IV access early; draw blood while cannulating (PCV/total solids at minimum). Oxygen if weak, collapsed or in respiratory compromise.
• Fluids: restore perfusion first. Balanced crystalloids are a sensible default in most cases (Hartmann’s/Lactated Ringer’s commonly used), but choose fluids based on the history and blood chemistry where possible.
• Shock boluses: typical clinicians’ practice discussed ranges for dogs and cats, but always tailor to the individual patient and follow your practice or hospital protocols. Reassess perfusion parameters after each bolus and repeat only if indicated.
• Once perfusion is restored, calculate ongoing fluids: maintenance + dehydration deficits + ongoing losses.

6.Analgesia and antiemetics — sensible symptom control

Clinical caveat: explain to owners that antiemetics reduce vomiting but don’t replace the need to reassess if clinical signs or demeanour don’t improve.

• Analgesia: use when indicated. Opioids relieve pain but can reduce appetite, alter temperature and slow GI transit. IV paracetamol can be a useful adjunct in dogs when you want analgesia without confounding heart‑rate assessment during resuscitation.
• Antiemetics:
• Maropitant is widely used and often makes patients brighten quickly; warn owners it can “mask” vomiting and advise return if lethargy, persistent inappetence or new/worsening blood occurs.
• Maropitant does not treat regurgitation — persistent “vomiting” after maropitant may actually be regurgitation or obstruction.
• Metoclopramide is useful for ileus/regurgitation in hospitalised patients; avoid if you strongly suspect a proximal GI obstruction (risk of worsening ruptures).
• Ondansetron is another option for severe nausea.
• Acid suppression: reserve PPIs for suspected gastric ulceration, significant GI bleeding or oesophagitis rather than routine use in every vomiting case.
• Antibiotics: don’t reflexively prescribe metronidazole for acute diarrhoea without evidence of a target infection. Follow stewardship guidance.

7.Minimum bloods with purpose

Focus: run tests that will change your immediate plan, not a scattergun panel.

• PCV/total solids: markers of haemoconcentration; repeat after resuscitation to track response.
• Biochemistry/electrolytes: azotaemia, K+, Na+, Cl−; patterns can hint at causes (e.g., hypochloraemic metabolic alkalosis can suggest gastric outflow obstruction).
• Haematology/blood smear: neutropenia or toxic change point to sepsis.
• Additional tests (case‑by‑case): pancreatic lipase, T4 in cats, urinalysis.

8.Imaging: use the modality that helps you decide

• Ultrasound: rapid screen for free fluid, organ pathology and abnormal intestinal motility. Look for two intestinal populations (dilated, fluid‑filled segments vs empty segments) and a hugely distended stomach — pattern recognition is often more valuable than finding the FB itself.
• Radiography: good for mineral/metal foreign bodies and to complement ultrasound pre‑theatre.
• Don’t forget the chest for possible oesophageal FBs — ptyalism, repeated hard swallows or failure to pass an oesophageal probe are clues.
• If imaging is inconclusive but clinical suspicion remains, an exploratory laparotomy (ex‑lap) may be diagnostic and therapeutic.

9.Differentials you’ll actually use (practical, age‑guided)

Always ask: is this a chronic problem that’s just flared?

• Puppies/kittens & young (<2 yrs): dietary indiscretion, foreign body/intussusception, parasites, toxins, infectious enteritis (e.g., parvovirus).
• Middle‑aged: food‑responsive disease, chronic enteropathy, pancreatitis, pyometra in entire bitches, prostatitis in males, metabolic disease (e.g., hypoadrenocorticism).
• Older: CKD, hepatic disease, neoplasia — but don’t forget the younger differentials still apply.

10.Discharge vs admit — practical guidance

• Consider discharge (symptomatic antiemetic ± analgesia and safety‑netting) for bright patients with normal vitals and minimal fluid loss.
• Admit for fluids, further bloods and imaging if there is concern on vitals, demeanour, dehydration or persistent vomiting.
• Communicate plans clearly: “If X happens we’ll escalate to Y” (e.g., admission + ultrasound or radiographs pre‑op).

11.Owner communications that keep patients safe

• Teach “fluid in vs fluid out”: if the patient can’t keep water down, come back.
• Explain the limitations of symptom control: “If vomiting continues despite antiemetic, or if there’s lethargy, refusal to eat, or new/worse blood, return immediately.”
• Reassure about small specks of blood vs large clots/pools — detail and trend matter.

12.Key take‑home points

Acute vomiters are routine until they’re not. Get the first minutes right — spot shock, decide vomiting vs regurgitation, start fluids appropriately — and most of the rest falls into place.

• Stabilise first: treat hypovolaemic shock before chasing every diagnosis.
• Distinguish vomiting from regurgitation — it changes the whole work‑up.
• Dogs in hypovolaemic shock tend to be tachycardic; cats can be bradycardic. Low temperature is worrying.
• Use fluids, analgesia and antiemetics thoughtfully and reassess after each intervention; tailor bolus sizes and rates to the patient and follow local protocols.
• Ultrasound is a powerful first look; X‑rays are helpful when they change your plan (e.g., identify radiopaque FBs or plan theatre).
• Steward antibiotics and acid suppressants — use when evidence or clinical indication supports them.
• Clear safety‑netting and owner education prevent most post‑discharge surprises.