While many of our Medgadget postings are focused on the latest technology or product approvals, we also like to focus on highlighting products/technologies that have significant impact in smaller markets. One such company is PHD Medical, founded in Canada in 2003, whose focus is on building platform-based technological solutions that migrate traditional services that are found in hospital to the home and community. Their core platforms each handle one aspect of the care spectrum; Diagnosis – Expert System (The sleep system also known as NPoses), Care Management – Etrending, and Consultative – TeleVisit. We were fortunate to discuss the Sleep System, NPoses, with the Medical Director of PHD Medical, Dr. Robert T. Brouillette. The NPoses system received the CE Mark in March of 2005 and FDA clearance in June of 2006, and has been used with over 5000 patients to date.
For many patients, the diagnosis process for sleep apnea can be inconvenient, expensive, and uncomfortable largely because of the need of performing overnight polysomnography, the gold standard for diagnosing sleep apnea. Often, sleep labs are not equipped to support pediatric patients, and not only is the child’s schedule disrupted, but also that of the parents. NPoses provides an affordable and convenient method for parents to document the child’s sleep data at home and provide it to the physician for diagnosis.
Janelle Chang, Medgadget: What percentage of the pediatric population suffers from sleep apnea?
Dr. Robert T. Brouillette, PHD Medical: Most people estimate that 1 to 3% of children have sleep apnea at any given time. In the United States, about 4 million babies are born per year and there are about 400,000 tonsillectomies, most of which are done for obstructive sleep apnea. Therefore the lifetime incidence may actually be closer to 10%. Many children snore, at least 10% at a given time. Snoring is the hallmark sign of sleep apnea in children as well as adults. Therefore, it can be difficult to identify a child with obstructive sleep apnea needing treatment from the more frequent children with simple snoring that does not need medical treatment.
Medgadget: What inspired you to develop this software?
Dr. Brouillette: Given the frequency of snoring in children and their frequency of obstructive sleep apnea in children it is impossible to imagine that laboratory attended polysomnography will be available to most children in need of testing – only a small fraction of existing sleep labs actually have pediatric capability. Polysomnography often cost as much as $1500 given that it must take place in a laboratory and be attended by an expert technician overnight.
We were looking for a better way utilize the technician, respiratory therapist and physician time and to remove the brick and mortar lab from the equation.
Considering most pediatric sleep labs have a 1:1 technician to patient ratio we have increased productivity 3 fold from a labor perspective, reduced capital cost of equipment by ~80% and virtually eliminated the physical space requirements of polysomnography laboratories for most studies.
Medgadget: Can you share the basic methodology behind NPoses?
Dr. Brouillette: PHD medical expert system takes data in from the referring physician’s request for consultation, a parental questionnaire (history), and data from overnight pulse oximetry. The analysis of the pulse oximetry tracing is based on the McGill Oximetry Score, which goes from 1 to 4. Category 1 is normal or inconclusive and categories two through four represent increasingly severe and frequent dips in hemoglobin saturation (the metric measured by pulse oximetry) consequent to episodes of obstructive sleep apnea. The PHD system uses an artificial intelligence engine to analyze the data received, and automatically writes a report and/or consultation to be sent back to the referring physician. The interpreting physician then reviews the report and/or consultation modifies it as needed, and sends it back to the referring physician.
Medgadget: How accessible is the software to a parent of a child with apnea i.e. does it require a physician or technician to set it up and interpret the results?
Dr. Brouillette: The system requires about one hour of technician time per study. A parent is sent an email link to an online questionnaire which effectively captures relevant patient history. The parent then comes to the office, clinic or laboratory and receives a brief instruction session on how to setup the equipment on their child. When the child goes to bed, the parents set the equipment up on the child, and remove it the next morning. During the night of the evaluation, the parents also record a log of sleep onset, wakenings and other nocturnal events. Parents return the equipment and the data is downloaded into our system for analysis and reporting. A respiratory therapist or sleep technician validates the data and sends it on to the interpreting physician who verifies the suggested diagnosis and report generated by the system and electronically validates the results- usually within 24 hours of test completion.
Medgadget: What is the clinical performance of the software performed to date? Is the software limited to a specific age range? Are there plans to expand to adult diagnosis?
Dr. Brouillette: The system has been validated for children 1 to 18 years old against the gold standard test for obstructive sleep apnea in children, in laboratory attended polysomnography. The system has a documented positive predictive value of 97% or higher, that is if the system predicts a child has obstructive sleep apnea that prediction will be validated in 97% of polysomnographies. We have recently published further validation in a study with colleagues from Rome, Italy (Pediatr Pulmonol. 2013; 48:754–760), in which we showed that night to night results were highly consistent. The system is based on dips in hemoglobin saturation consequent to obstructive sleep apnea. Children with milder sleep apnea may not have dips in hemoglobin saturation but still have a degree of sleep apnea. Thus the sensitivity and negative predictive value is low and inconclusive oximetry studies can be followed up clinically or by using the gold standard expensive test of polysomnography. This depends on physician and parental preference and local standards of care.
Our software is specifically targeted for pediatric obstructive sleep apnea. Oximetry has been used to rule in obstructive sleep apnea in highly symptomatic patients or rule out obstructive sleep apnea in patients that are unlikely to have apnea. Our software platform can be modified for use in adults and this is in our future plans.
Medgadget: What is the overall upcoming focus of PHD Medical? What are the company’s goals for the second half of 2013 and going into 2014?
Dr. Brouillette: In the next year, from a technological point of view, we are focused on expanding on our core platforms (functionality and process) and the unification of the platforms to provide a seamless care cycle for specific diseases.
From a commercial perspective, and specific to Pediatric Sleep, we are launching a campaign to equip pediatric offices with our technology. This will allow pediatricians and ENT surgeons to effectively turn a clinical office into a pediatric sleep lab.
Editorial by Dr. Broullette in New England Journal of Medicine: Let’s CHAT about Adenotonsillectomy