Transmission delay performance in telemedicine: A case study.

Given the prevalence of chronic health conditions, such as diabetes, obesity, epilepsy, and cardiovascular diseases, telemedicine technologies are increasingly adopted to help patients better manage their care and treat these diseases at home. These emerging telemedicine systems have been deployed and tested in a number of different health programs and hospitals. However, due to the lack of dedicated and reliable networking infrastructure, achieving real-time data collection is very challenging task. In this paper, we conduct a comprehensive analysis on the delay issues presented during the use of a store and forward telemonitoring system for congestive heart failure patients in urban Philadelphia. Results from this analysis reveal that 10.3% of the patient measurements experience delays of longer than 12 hours. Delays of up to several days occurred in 15.38% these patients who went on to be hospitalized. These delay issues exposed from urban scale real systems have direct impact on the quality of remote health care, causing late diagnosis and intervention especially when patients are experiencing acute exacerbations. Our investigation results essentially call for regulations on telemedicine systems with an emphasis on their temporal constraints.

Functional Alarms for Systems of Interoperable Medical Devices.

Alarms are essential for medical systems in order to ensure patient safety during deteriorating clinical situations and inevitable device malfunction. As medical devices are connected together to become interoperable, alarms become crucial part in making them high-assurance, in nature. Traditional alarm systems for interoperable medical devices have been patientcentric. In this paper, we introduce the need for an alarm system that focuses on the correct functionality of the interoperability architecture itself, along with several considerations and design challenges in enabling them.

Model-Driven Safety Analysis of Closed-Loop Medical Systems.

In modern hospitals, patients are treated using a wide array of medical devices that are increasingly interacting with each other over the network, thus offering a perfect example of a cyber-physical system. We study the safety of a medical device system for the physiologic closed-loop control of drug infusion. The main contribution of the paper is the verification approach for the safety properties of closed-loop medical device systems. We demonstrate, using a case study, that the approach can be applied to a system of clinical importance. Our method combines simulation-based analysis of a detailed model of the system that contains continuous patient dynamics with model checking of a more abstract timed automata model. We show that the relationship between the two models preserves the crucial aspect of the timing behavior that ensures the conservativeness of the safety analysis. We also describe system design that can provide open-loop safety under network failure.

Biomedical devices and systems security.

Medical devices have been changing in revolutionary ways in recent years. One is in their form-factor. Increasing miniaturization of medical devices has made them wearable, light-weight, and ubiquitous; they are available for continuous care and not restricted to clinical settings. Further, devices are increasingly becoming connected to external entities through both wired and wireless channels. These two developments have tremendous potential to make healthcare accessible to everyone and reduce costs. However, they also provide increased opportunity for technology savvy criminals to exploit them for fun and profit. Consequently, it is essential to consider medical device security issues. In this paper, we focused on the challenges involved in securing networked medical devices. We provide an overview of a generic networked medical device system model, a comprehensive attack and adversary model, and describe some of the challenges present in building security solutions to manage the attacks. Finally, we provide an overview of two areas of research that we believe will be crucial for making medical device system security solutions more viable in the long run: forensic data logging, and building security assurance cases.