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.
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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
