Should we encourage dogs in healthcare settings?

Ever since I took Cassie (a 3-year-old chocolate lab) to the Heart Function Clinic, I have wondered, "Am I missing something here?" I mean, the beneficial effects on anxiety and stress are obvious, and almost all patients would agree. After Cassie was finished licking the staff, she would befriend patients with a smile and snuggle, sometimes lying down for a tummy rub. The secretaries all loved her, which I found to be an unnecessary but joyous distraction. Patients asked when they could come back and see her (not me).Sure, we know that service dogs can be ‘sight’ for a blind person, or a comfort companion for an emotional patient. Patients are welcome to bring leashed animal with them on visits (a somewhat uncommon occurrence). But what might we expect by using the dog’s greatest asset: her NOSE. A dog’s sense of smell is 10,000-100,000 times better than that of a human. For every scent receptor a human has, a dog has about 50. They have two parts to their olfactory system: the main olfactory epithelium and the vemornasal organ (‘Jacobson’s Organ’), located just above the roof of the mouth, specialising in pheromone analysis. Twelve percent of each breath goes straight to the olfactory region, where odour molecules are deposited and identified. (1) Read: Medical wisdom They can sniff separately with each nostril, allowing them to lateralize the origin of scents. Furthermore, their olfactory bulb (brain centre for smell) is larger than other mammals, which in retrospect makes ‘sense.’Dogs can detect infection (clostridium difficile,[2] COVID, malaria), and identify many types of cancer (including breast, lung and bladder). In one study, after only three weeks of training, they were able to identify lung cancer patients from breath samples 99% of the time, and breast cancer 88-98% of the time. (3,4)I remember Helsinki airport using sniffer dogs to screen travellers at the height of the pandemic—how clever is that! Forget the swab-up-the-nasopharynx, the test kit and the inconvenient wait, just get Marley to sniff you at the luggage carousel. In a hospital outbreak of C. difficile, such timely diagnosis is vital in mitigating spread. The standard cytotoxin assay can take one to two days (at significant cost and some risk): a dog can screen a hospital ward of patients for C. difficile in less than 10 minutes.Read: Calories, vitamins and supplementsI guess we haven’t engaged sniffer dogs in healthcare because we are waiting for large randomised controlled trials, so as to overcome some of the challenges thrown up when we call Cassie ‘a medical device.’ A device that is expected to adhere to high standards of obedience, alertness, and behaviour. Whether in the role as a pacifier in the ER, or as a diagnostician at the airport, they have us beat—paws down! So why the delay?References:Canine Olfaction: physiology, behaviour and possibilities for Practical Applications. Kokocinska-Kusia, A. Animals (Aug 2021): doi 10.3390/ani11082463Using a dog’s superior olfactory sensitivity to identify C Difficile in stool and patients: proof of principle study. Bomers, MK et al. BMJ (Dec 2012) vol 345 p7-9 Diagnostic Accuracy of Canine Scent Detection in Early- and Late-Stage Lung and Breast Cancers. McCulloch, M et al. Integrative Cancer Therapies 5(1) 2006 p30-39: doi 10.1177/1534735405285096COVID-19 sniffer dog experimental training: which protocol and which implications for reliable identification? Angeletti, S et al. J Med Virology (June 2021): doi.org/10.1002/jmv.27147The dogs being trained to smell cancer and disease. Channel 4 News (2018)

Should we encourage dogs in healthcare settings?

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