Dunsmuir D, Karlen W, Gan H, Chiu M, Petersen CL, Dumont GA, Ansermino JM. The design of a respiratory rate mobile application. In: International Anesthesia Research Society Annual Meeting. 2014.

Crede S, Merwe G, Hutchinson J, Woods D, Karlen W, Lawn J. Where do pulse oximeter probes break?. Journal of clinical monitoring and computing. 2014; 28(3):309--14.      [DOI]      [File] 

Garde A, Karlen W, Dehkordi P, Wensley D, Ansermino JM, Dumont GA. Analysis of Oxygen Saturation in Children with Obstructive Sleep Apnea Using the Phone-Oximeter. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). Osaka: 2013. p. 2531--4.

Karlen W, Ansermino JM, Dumont GA, Scheffer C. Detection of the optimal region of interest for camera oximetry. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). Osaka: 2013. p. 2263--6.      [DOI]      [File] 

Garde A, Karlen W, Dehkordi P, Ansermino JM, Dumont GA. Empirical mode decomposition for respiratory and heart rate estimation from the photoplethysmogram. In: Murray, Alan, editors. Computing in Cardiology (CinC). Zaragoza: IEEE; 2013. p. 799--802.     [File] 

Karlen W. Empowering Home-Based Carers with Medical Applications on Mobile Phones in the Western Cape. In: Sustainable Rural Health Research Day. Worcester, South Africa: 2013.

Karlen W, Ettinger KM. Ethics Consultation In Mobile Health Application Design. In: Abstracts of the Global Health & Innovation Conference. Yale, USA: Unite for Sight; 2013 Apr..

Brouse CJ, Karlen W, Dumont GA, Myers D, Cooke E, Stinson J, Lim J, Ansermino JM. Monitoring nociception during general anesthesia with cardiorespiratory coherence. Journal of clinical monitoring and computing. 2013; 27(5):551--60.      [DOI]      [File] 

Karlen W, Raman S, Ansermino JM, Dumont GA. Multiparameter respiratory rate estimation from the photoplethysmogram. IEEE Transactions on Biomedical Engineering. 2013; 60(7):1946--53.      [DOI]      [File] 

Karlen W, Petersen C, Gow J, Ansermino JM, Dumont GA. Photoplethysmogram Processing Using An Adaptive Single Frequency Phase Vocoder Algorithm. In: Fred, A and Filipe, J and Gamboa, H, editors. BIOSTEC 2011, CCIS 273. Berlin Heidelberg: Springer-Verlag; 2013. p. 31--42.      [DOI]      [File] 

Karlen W. Pulse Oximeters on Mobile Phones for Rural Health Care. In: Sustainable Rural Health Research Day. Worcester, South Africa: 2013.

Dehkordi P, Garde A, Karlen W, Wensley D, Ansermino JM, Dumont GA. Pulse rate variability compared with heart rate variability in children with and without sleep disordered breathing. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). 2013. p. 6563--6.

Dehkordi P, Garde A, Karlen W, Wensley D, Ansermino JM, Dumont GA. Pulse Rate Variability in Children with Disordered Breathing During Different Sleep Stages. In: Computing in Cardiology (CinC). Zaragoza: IEEE; 2013. p. 1015 -- 8.     [File] 

Karlen W, Lim J, Ansermino JM, Dumont GA, Scheffer C. Recognition of correct finger placement for photoplethysmographic imaging. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). Osaka: 2013. p. 7480--3.      [DOI]      [File] 

Chiu M, Karlen W, Dunsmuir D, Görges M, Gan H, Lim J, Ansermino JM. The RRate Mobile App; Developing a robust measure of respiratory rate for use in low-resource settings. In: Child and Family Research Institute Summer Student Research Day. Vancouver, CA: 2013.

Raman S, Brouse CJ, Karlen W, Dumont GA, Ansermino JM. A Data Fusion Approach for RR estimation from PPG (STA Engineering Challenge). In: Proceedings of the 2012 Society for Technology in Anesthesia Annual Meeting. West Palm Beach: 2012.

Karlen W, Ansermino JM, Dumont G. Adaptive pulse segmentation and artifact detection in photoplethysmography for mobile applications. In: 2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society. San Diego: IEEE; 2012 Aug.. p. 3131--3134.      [DOI]      [File] 

Karlen W, Lim J, Ansermino JM, Dumont GA, Scheffer C. Design challenges for camera oximetry on a mobile phone. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). 2012 Jan.. p. 2448--51.      [DOI]      [File] 

Brouse CJ, Karlen W, Myers D, Cooke E, Stinson J, Lim J, Ansermino JM. Measuring Adequacy of Analgesia with Cardiorespiratory Coherence. In: Abstracts of the 2012 Annual Meeting of the Society for Technology in Anesthesia (STA). West Palm Beach: Anesthesia and analgesia; 2012. p. S8.      [DOI]      [File] 

Karlen W, Kobayashi K, Ansermino JM, Dumont GA. Photoplethysmogram signal quality estimation using repeated Gaussian filters and cross-correlation. Physiological Measurement. 2012 Sep.; 33(10):1617--29.      [DOI]      [File] 

Chandler JR, Cooke E, Petersen C, Karlen W, Froese N, Lim J, Ansermino JM. Pulse oximeter plethysmograph variation and its relationship to the arterial waveform in mechanically ventilated children. Journal of clinical monitoring and computing. 2012 Jun.; 26(3):145--51.      [DOI]      [File] 

Brouse CJ, Karlen W, Dumont GA, Myers D, Cooke E, Stinson J, Lim J, Ansermino JM. Real-time cardiorespiratory coherence detects antinociception during general anesthesia. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). 2012 Jan.. p. 3813--6.      [DOI]      [File] 

Dunsmuir D, Petersen C, Karlen W, Lim J, Ansermino JM. The Phone Oximeter for Mobile Spot-Check. In: Abstracts of the 2012 Annual Meeting of the Society for Technology in Anesthesia (STA). West Palm Beach: Anesthesia and analgesia; 2012. p. S21.

Hudson J, Nguku SM, Sleiman J, Karlen W, Dumont GA, Petersen C, Warriner CB, Ansermino JM. Usability testing of a prototype Phone Oximeter with healthcare providers in high- and low-medical resource environments. Anaesthesia. 2012; 67(9):957--67.      [DOI]      [File] 

Karlen W, Petersen C, Gow J, Ansermino JM, Dumont GA. An Adaptive Single Frequency Phase Vocoder For Low-power Heart Rate Detection. In: BIODEVICES 2011 - Proceedings of the International Conference on Biomedical Electronics and Devices, Rome, Italy, January 26-29, 2011. INSTICC Press; 2011. p. 30--35.

Karlen W, Pickard A, Ansermino JM. Automated Validation of Capillary Refill Time Measurements in Children. In: UBC Department of Anesthesiology, Pharmacology and Therapeutics 5th Annual Research Day. Vancouver, CA: 2011. p. 43.

Karlen W, Pickard A, Daniels J, Kwizera A, Ibingira C, Dumont GA, Ansermino JM. Automated Validation of Capillary Refill Time Measurements Using Photo-Plethysmogram from a Portable Device for Effective Triage in Children. In: 2011 IEEE Global Humanitarian Technology Conference (GHTC). IEEE; 2011 Oct.. p. 66--71.      [DOI]      [File] 

Myers D, Brouse CJ, Cooke E, Lim J, Karlen W, Montgomery CJ, Ansermino JM. Comparison between number of skin conductance fluctuations and heart rate for detecting nociception in children during anesthesia. In: 3rd World Congress of Total Intravenous Anesthesia and Target Controlled Infusion (TIVA-TCI 2011). Singapur: 2011.

Karlen W, Dumont GA, Petersen C, Gow J, Lim J, Sleiman J, Ansermino JM. Human-centered Phone Oximeter Interface Design for the Operating Room. In: Traver, Vicente and Fred, Ana and Filipe, Joaquim and Gamboa, Hugo, editors. Proc. of the Int. Conf. on Health Informatics (HEALTHINF). Rome, Italy: SciTePress - Science and and Technology Publications; 2011. p. 433--8.      [DOI]      [File] 

Stinson J, Pickard A, Cooke E, Myers D, Karlen W, Ansermino JM. Inter-observer and intra-observer repeatability of capillary refill time. In: International Anesthesia Research Society Annual Meeting. Vancouver, CA: 2011.

Karlen W, Blackstock M, Ansermino JM. Location independence in patient monitoring. In: Abstracts of the 2011 Annual Meeting of the Society for Technology in Anesthesia (STA). Las Vegas: Anesthesia and Analgesia; 2011 Aug.. p. S37.      [DOI]      [File] 

Pickard A, Karlen W, Ansermino JM. Medical intelligence article: capillary refill time: is it still a useful clinical sign?. Anesthesia and analgesia. 2011 Jul.; 113(1):120--3.      [DOI]      [File] 

Karlen W, Brouse CJ, Cooke E, Ansermino JM, Dumont GA. Respiratory rate estimation using respiratory sinus arrhythmia from photoplethysmography. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). Boston: 2011 Aug.. p. 1201--4.      [DOI]      [File] 

Karlen W, Floreano D. SleepPic. Hardware Developments for a Wearable On-line Sleep and Wake Discrimination System. In: Babiloni, Fabio and Fred, Ana and Filipe, Joaquim and Gamboa, Hugo, editors. Proc. of the International Conference on Bio-inspired Systems and Signal Processing (BIOSIGNALS). Rome, Italy: SciTePress; 2011. p. 132--7.

Karlen W, Hudson J, Lim J, Petersen C, Anand R, Dumont G, Ansermino JM. The Phone Oximeter. In: IEEE Engineering in Medicine and Biology Society Unconference. Boston, USA,: 2011.

Chandler J, Cooke E, Hosking M, Froese N, Karlen W, Ansermino JM. Volume responsiveness in children, a comparison of static and dynamic indices. In: International Anesthesia Research Society Annual Meeting. Vancouver, CA: 2011.

Brouse CJ, Karlen W, Myers D, Cooke E, Stinson J, Lim J, Dumont GA, Ansermino JM. Wavelet transform cardiorespiratory coherence detects patient movement during general anesthesia. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). 2011 Aug.. p. 6114--7.      [DOI]      [File] 

Pickard A, Karlen W, Petersen C, Ansermino JM. A novel method of measuring capillary refill time using photo-plethysmography. In: UBC Department of Anesthesiology, Pharmacology and Therapeutics 4th Annual Research Day. Vancouver, CA: 2010.

Karlen W, Floreano D. Adaptive Sleep-Wake Discrimination for Wearable Devices. IEEE Transactions on Biomedical Engineering. 2010 Dec.; 58(4):920--6.      [DOI]      [File] 

Karlen W, Petersen C, Pickard A, Dumont GA, Ansermino JM. Capillary Refill Time Assessment Using a Mobile Phone Application. In: Proceedings of the 2010 Annual Meeting of the American Society Anesthesiologists. San Diego: American Society of Anesthesiologists; 2010. p. A575.     [File]