Hypertension in Dogs: Welfare and Management
Overview of Canine Hypertension
Hypertension (sustained elevated blood pressure) is common in dogs, primarily as secondary hypertension associated with underlying diseases: chronic kidney disease (most common), hyperadrenocorticism (Cushing's disease), hypothyroidism (in some cases), phaeochromocytoma, and primary hyperaldosteronism. Primary (idiopathic) hypertension exists in dogs but is less common than in cats. Normal blood pressure in dogs is approximately 100-140mmHg systolic; hypertension is defined as >160mmHg systolic.
Welfare Consequences of Hypertension
Hypertension causes 'silent' progressive organ damage. Target organ damage includes: ocular effects (retinal haemorrhage, retinal detachment causing sudden blindness — the most clinically visible manifestation); renal effects (glomerular hypertension accelerating CKD progression); cardiac effects (left ventricular hypertrophy); neurological effects (cerebrovascular accidents, seizures, altered mentation). Each causes significant welfare impact; sudden blindness from hypertensive retinopathy is acutely distressing.
Diagnosis and Blood Pressure Measurement
Blood pressure measurement in veterinary practice requires validated oscillometric devices or Doppler ultrasound technique. Multiple measurements in a calm environment (allowing acclimatisation before measuring) improve accuracy and reduce 'white coat' hypertension. ACVIM guidelines recommend: >5 readings, discard first; measure in a quiet area with the owner present; avoid immediate post-exercise measurement. Interpreting blood pressure in context of the clinical examination and underlying disease is essential.
Treatment
The underlying cause should be treated first (controlling Cushing's disease, managing CKD, thyroid supplementation). Specific antihypertensive drugs: amlodipine (calcium channel blocker) is the most effective drug for significant hypertension in dogs; benazepril or enalapril (ACE inhibitors) are useful for proteinuric CKD-associated hypertension; telmisartan (ARB) is an alternative. Treatment targets: systolic BP <150mmHg. Response monitoring: BP recheck 1-2 weeks after initiating or changing treatment.
Long-term Monitoring
Hypertension management requires long-term commitment. Regular BP monitoring (every 1-3 months depending on stability) tracks treatment response. Ophthalmoscopy at each recheck assesses for retinal changes. Urinalysis and renal function assessment monitors CKD progression. Owners should be aware of acute signs of hypertensive emergency: sudden blindness (eyes appear normal externally), seizures, or acute ataxia warrant emergency assessment. Well-managed hypertension significantly reduces the rate of organ damage progression.