Journal of Feline Medicine and Surgery

Practical relevance Neutering kittens at an early age, typically between 6 and 14 weeks, has received increasing attention and gained prominence in recent years, particularly in the United States and in shelter medicine in the UK. However, in private practice it has yet to be generally endorsed.

Global importance Among many of the animal welfare charities, early neutering is seen as a crucial step in conquering and controlling cat overpopulation.

Clinical challenges Physiological differences between kittens and adult cats are very important to consider before undertaking elective early neutering. Increased sensitivity to drugs, prolongation of effects and a limited capacity for cardiovascular compensation are the principal anaesthetic concerns in kittens.

Evidence base The optimal age for neutering, traditionally deemed to be between 5 and 8 months, is now questioned, as short- and longer-term studies demonstrate no significant behavioural and physical advantages conferred by traditional-age neutering. Furthermore, a number of safe anaesthetic and surgical protocols have been documented that produce lower morbidity and similar mortality rates in early-age neuters compared with traditional-age neuters.

Practical relevance Blood transfusions are a potentially life-saving procedure that are within the reach of most small animal practitioners. Only minimal equipment is required.

Patient group Any cat with clinical signs attributable to a reduced red blood cell mass that is affecting oxygen transport (as a result of reduced packed cell volume or acute blood loss) is a potential candidate for a transfusion.

Clinical challenges Although the principles of transfusion medicine are not complicated, there can be fatal consequences if certain steps are omitted.

Diagnostics Blood typing kits and blood filters are readily available from veterinary wholesalers, laboratories and blood banking services.

Evidence base Over the past three decades, a substantial body of clinical research and reports has built up covering feline blood types and transfusion medicine. This article draws on that research to provide clinical guidance aimed at all veterinarians in feline or small animal practice who either currently practise transfusion medicine or plan to do so.

Practical relevance The increased availability of indirect blood pressure monitoring devices in clinical practice over the past decade has highlighted the significance of systemic hypertension in the feline population. Without routine monitoring and appropriate intervention, cats with undiagnosed systemic hypertension may first be presented with sudden-onset blindness as a consequence of either hyphaema or retinal detachment.

Clinical challenges The primary aim in the early diagnosis and treatment of systemic hypertension is prevention of hypertensive target organ damage (with respect to the eye, kidney, cardiovascular and central nervous systems, in particular). A prerequisite is a knowledge of the pathophysiological mechanisms and disease conditions that may contribute to the development of hypertension. This allows the clinician to determine those cases in which blood pressure assessment and longitudinal monitoring is essential and can assist in determining appropriate therapeutic strategies for control of blood pressure. Recent studies have also begun to explore the relationship that systemic hypertension may have with proteinuria and the progression of kidney disease.

Patient group The geriatric cat appears most susceptible to the development of systemic hypertension, and monitoring of systolic blood pressure is often advocated as part of a routine health screen in cats over 9–12 years old. Consideration must also be given to cats suspected of having an underlying disease such as chronic kidney disease or hyperthyroidism, or which are receiving therapeutic agents, irrespective of their age.

Evidence base Much of our understanding of the pathogenesis of feline hypertension is extrapolated from studies performed in experimental animal models or in human patients, and interspecies differences are often poorly understood.

Practical relevance The clinical importance of feline hypertension has been recognised for many years and most feline practitioners are quite familiar with this syndrome. Once systemic hypertension is identified, long-term management of the patient is needed to avoid catastrophic (eg, blindness due to retinal detachment) or subtle (eg, accelerated renal damage) target organ damage.

Patient group Feline systemic hypertension is most commonly a complication of renal disease and hyperthyroidism, both diseases of older feline patients. By 15 years of age, the probability of having at least one of these two diseases is high. As well cared for cats are living longer, optimal long-term management of feline hypertension in patients with concurrent diseases is an issue of clinical importance.

Clinical challenges Obtaining accurate blood pressure measurements in patients that are anxious, fractious or just plain uncooperative remains a significant issue in feline medicine, as does confident analysis of results from these patients.

Diagnostics Careful measurement of systolic blood pressure using Doppler or oscillometric techniques in conjunction with evaluation for evidence of hypertensive choroidopathy (funduscopic examination) and hypertensive cardiac changes (thoracic auscultation) are essential to the diagnosis of systemic hypertension in cats. Other diagnostic techniques, including evaluation of renal and thyroid function, are needed to detect the underlying disease condition.

Evidence base Numerous well-designed clinical studies have greatly advanced our understanding of the most appropriate methods of diagnosis and therapy of feline hypertension.

Surgical findings An adenocarcinoma of the uterine stump with abdominal metastases is described in a 12.5-year-old incompletely ovariohysterectomised domestic shorthair cat. At the time of presentation, the adenocarcinoma had metastasised to the right perirenal lymph node, the abdominal aorta and the right ureter, resulting in the formation of a large cystic structure. This had compressed and displaced surrounding structures, including the abdominal vena cava and the right kidney, and formed multiple adhesions to the body wall and adjacent abdominal structures. Metastatic extension to the aorta had resulted in its regression into a 2 mm diameter non-pulsatile vessel.

Practical relevance Only one case of uterine adenocarcinoma has previously been reported in an ovariohysterectomised cat. As such, this represents a very unusual and severe complication following an incomplete ovariohysterectomy. Invasion of the tumour tissue into surrounding structures created further complications.

Case presentation and surgical intervention A 3-year-old cat was presented with a recent history of dysphagia and intermittent regurgitation. Radiography revealed a bony oesophageal foreign body at the level of the thoracic inlet. Endoscopic retrieval was attempted but resulted in severe dyspnoea due to the development of pneumomediastinum, pneumothorax and subcutaneous emphysema secondary to perforation of the oesophageal wall. Immediate surgical exploration was carried out. Extensive necrosis of the oesophagus resulting from the presence of the foreign body led to a decision to perform an oesophageal resection and anastomosis.

Clinical relevance This is the first clinical report of a cat treated successfully by oesophagectomy following oesophageal perforation due to an obstructive foreign body. The authors suggest that prompt surgical intervention, the ability to convert to a surgical procedure under the same anaesthetic as a non-surgical retrieval, placement of a gastrostomy tube and the availability of advanced anaesthetic and critical care support are important factors to consider when managing feline patients with a perforating oesophageal foreign body.

Despite neutering being one of the most common veterinary procedures, questions remain about what constitutes best practice, and when is the ideal time to neuter. These were the focus of attention at a meeting of The Cat Group, held in London last September, to which representatives from the UK veterinary schools, and a number of other veterinary experts, were invited. This article presents a summary of the discussions.