Seattle, USA
EditorAs anaesthetists, we have become increasingly dependent on the use of integrated monitoring display units to relay information about patient vital signs to us. Unfortunately, we are increasingly distracted from the information display, with evidence of a lack of monitor observation at critical periods of anaesthesia such as induction and recovery.1 The increasing requirement for cardiac anaesthetists to perform intraoperative transoesophageal echocardiography has been shown to greatly reduce observation of monitors.2 We have recently been able to test a heads up display device which relays the integrated monitor display to a look through display worn over one eye. The Nomad Heads Up Display, Microvision, Bothall, Washington, USA, was originally developed for the recreational aviation industry to enable non instrument certified pilots to view their control display whilst looking out of the aircraft.3 The same technology is starting to be used for industrial applications and more recently in the medical field, by interventional radiologists performing ultrasound guided biopsies, and cardiologists performing atrial septal defect closure.4
This type of technology would seem to lend itself to our speciality. The patients we are being asked to anaesthetize are becoming increasingly challenging, highlighting the need for vigilant monitoring particularly during induction of anaesthesia and placement of additional monitoring lines. At our institution, we utilized the device whilst positioning pulmonary artery catheters, which resulted in quicker successful placement.5 We have also undertaken a small study with our anaesthesia residents during critical incident training in our anaesthesia simulator. We showed that residents wearing the device were significantly quicker at detecting myocardial ischaemia on the monitor than a control group whilst performing tasks that distracted them from their integrated display monitor. None of the residents felt that the device interfered with their ability to perform necessary tasks.
There is little published data on the use of such technology in anaesthesia. There is only one reported preliminary trial in a clinical environment where a similar device was equally well received.6 We feel that the device specifically may be of use to anaesthetists performing transoesophageal echocardiography. The common practice in the UK is for the anaesthetist responsible for the case to perform intraoperative echocardiography. The use of such a display would enable closer patient monitoring whilst undertaking this task.
M. J. Platt
Seattle, USA
References
1 Loeb RG. Monitor surveillance and vigilance of anesthesia residents. Anesthesiology 1994; 80: 52733[ISI][Medline]
2 Weinger MB, Herndon OW, Gaba DM. The effect of electronic record keeping and trans oesophageal echocardiography on task distribution, workload, and vigilance during cardiac anesthesia. Anesthesiology 1997; 87: 14455[ISI][Medline]
3 Nomad Augmented Vision System, Microvision Product Information, Microvision, Bothall, WA, 19932003 (www.microvision.com)
4 Reisman M, Gray WA, Ormerod DF, Hyde JP. Use of a head-mounted confluent display of fluoroscopic and echocardiographic images to enhance operator feedback during catheter deployed closures of cardiac septal defects. 2003, 10th Annual Medicine Meets Virtual Reality Conference, Newport Beach, California. www.mvis.com/pdfs/mmvr.pdf
5 Ross B, Naluai-Cecchini A, Omerod DF, et al. Use of a head mounted display of patient monitoring data to enhance anesthesiologists response to abnormal clinical events. Society of Technology in Anesthesia Meeting, Annual Meeting 2002. www.anestech.org/Publications-Abstracts.php
6 Block FE, Vablok DO, McDonald JS. Clinical evaluation of the heads up display of anesthesia data. Preliminary communication. Int J Clin Monit Comput 1995; 12: 214[ISI][Medline]