Development and evaluation of hand-held robotic technology for safe and successful peripheral intravenous catheterization on pediatric patients

Peripheral IntraVenous Catheterization (PIVC) is often required in hospitals to fulfil urgent needs of blood sampling or fluid/medication administration. Despite of the importance of a high success rate, the conventional PIVC operation suffers from low insertion accuracy especially on young pediatric patients. On average, each pediatric patient is submitted to 2.1 attempts before venous access is obtained, with around 50% failure for the first attempt. The risks of such multiple attempts can be severe and life-threatening as they can cause serious extravasation injuries. Given the levels of precision and controllability needed for PIVC, robotic systems show a good potential to effectively assist the operation and improve its success rate. Therefore, this study aims to provide such robotic assistance by focusing on the most challenging and error-prone parts of the operation. In order to understand the difficulties of a pediatric PIVC, a survey investigation is conducted with specialists at the beginning of this research. The feedbacks from this survey indicates an urgent need of a hand-held robot to assist in the catheter insertion control to precisely access the target vein. To achieve the above goal, a novel venipuncture detection system based on sensing the electrical impedance of the contacting tissue at the needle tip has been proposed and developed. Then several ex-vivo and in-vivo experiments were conducted to assess this detection system. Experimental results show that this system can be highly effective to detect venipuncture. Subsequently, based on this venipuncture detection system, four different handheld robots have been developed to provide different levels of autonomy and assistance while executing a PIVC insertion: 1. SVEI, short for \u2018Smart Venous Enter Indicator\u2019, is the simplest device without actuation. The user needs to do the whole PIVC operation, and this device only provides an indication of venipuncture by lighting up an LED. 5 2. SAID, short for \u2018Semi-Autonomous Intravenous access Device\u2019, integrates a motor to control the catheter insertion. The user is required to hold the device still and target it to a vein site. He/She then activates the device. The device inserts the catheter automatically and stops it when venipuncture is detected. 3. SDOP, short for \u2018Smart hand-held Device for Over-puncture Prevention\u2019, integrates a latch-based disengage mechanism to prevent over-puncture during PIVC. The user can keep the conventional way of operation and do the insertion manually. At the moment of venipuncture, the device automatically activates the disengage mechanism to stop further advancement of the catheter. 4. CathBot represents \u2018hand-held roBot for peripheral intravenous Catheterization\u2019. The device uses a crank-slider mechanism and a solenoid actuator to convert the complicated intravenous catheterization motion to a simple linear forward motion. The user just needs to push the device\u2019s handle forwards and the device completes the whole PIVC insertion procedure automatically. All the devices were characterized to ensure they can satisfy the design specifications. Then a series of comparative experiments were conducted to assess each of them. In the first experiment, 25 na\uefve subjects were invited to perform 10 trials of PIVC on a realistic baby arm phantom. The subjects were divided into 5 groups, and each group was asked to do the PIVC with one device only (SVEI, SAID, SDOP, CathBot and regular iv catheter). The experimental results show that all devices can provide the needed assistance to significantly facilitate and improve the success rates compared to the conventional method. People who have no experience of PIVC operation before can achieve considerably high success rates in robot-assisted PIVC (86% with SVEI, 80% with SAID, 78% with SDOP and 84% with CathBot) compared to the control group (12%) who used a regular iv catheter. Also, all 5 subjects using SVEI, 3 out of 5 subjects using SAID, 2 out of 5 subjects using SDOP and 4 out of 5 subjects using CathBot were able to successfully catheterize the baby arm phantom on their first attempt, while no subjects in the control group succeeded in their first attempts. Since SVEI showed the best results, it was selected for the second round of evaluation. In the second experiment, clinicians including both PIVC experts and general clinicians were invited to perform PIVC on a realistic baby arm phantom with 3 trials using SVEI and 3 trials in the conventional way. The results demonstrate that SVEI can bring great benefits to both specialists and general clinicians. The average success rates were found to be significantly improved from 48.3% to 71.7% when SVEI was used. The experimental results reveal that all experts achieved better or equal results with SVEI compared to the conventional method, and 9 out of 12 non-experts also had better or equal performance when SVEI was used. Finally, subjective feedback acquired through post-trial questionnaires showed that all devices were highly rated in terms of usability. Overall, the results of this doctoral research support continued investment in the technology to bring the handheld robotic devices closer to clinical us

Vestibular contribution to bodily self-consciousness and multisensory cortical processing

How does the self relate to the body? Bodily self-consciousness, i.e. the sense of being a subject bound to a body, involves a first-person perspective (1PP), i.e. the sense of being directed at the world. Prior research suggests that bodily self-consciousness depends on brain mechanisms integrating multisensory bodily signals. However, the specific multisensory mechanisms of 1PP are poorly understood. Here, I defend the thesis that the vestibular system, i.e. the sensory system encoding rotational and linear accelerations of the head, contributes to 1PP and related multisensory processing in the brain. The first part of my thesis presents experimental evidence showing that 1PP was influenced by multisensory conflict about the direction of gravity and the location of the body. 1PP depended on integrated visual-vestibular signals and was functionally distinct from another aspect of bodily self-consciousness: self-identification, i.e. the feeling that a particular body is âmineâ. The second part of my thesis presents the electrical neural correlates by which vestibular stimulation affected somatosensory and visual cortical processing. Passive whole-body yaw rotation naturally and selectively stimulated the vestibular system while the evoked responses to somatosensory or visual stimuli were recorded by electroencephalography. Electrical neuroimaging analysis showed temporal-specific vestibular effects on somatosensory and visual evoked potentials, localized by source estimations to distinct regions of the somatosensory, visual, and vestibular cortical networks. Collectively, the results from my thesis suggest that the vestibular system contributes to 1PP and multisensory cortical processing and imply that the vestibular system should not be neglected when studying higher brain function and neurobiological mechanisms of consciousness

The Second Conference on Lunar Bases and Space Activities of the 21st Century, volume 1

These papers comprise a peer-review selection of presentations by authors from NASA, LPI industry, and academia at the Second Conference (April 1988) on Lunar Bases and Space Activities of the 21st Century, sponsored by the NASA Office of Exploration and the Lunar Planetary Institute. These papers go into more technical depth than did those published from the first NASA-sponsored symposium on the topic, held in 1984. Session topics covered by this volume include (1) design and operation of transportation systems to, in orbit around, and on the Moon, (2) lunar base site selection, (3) design, architecture, construction, and operation of lunar bases and human habitats, and (4) lunar-based scientific research and experimentation in astronomy, exobiology, and lunar geology