Page 39 - JSOM Winter 2025

TABLE 1 Survey Questions and Results
No. (%) of respondents
Strongly Somewhat Neither agree Somewhat Strongly
Statement disagree disagree nor disagree agree agree
The SAM IO is easy to use. 6 (6) 17 (16) 9 (8) 4 (44) 27 (25)
The SAM IO offers a better tactile feel when the bone
is penetrated when compared to the EZ-IO. 22 (21) 30 (28) 30 (28) 18 (17) 6 (6)
When using the SAM IO, squeezing of the hand
trigger was difficult. 30 (28) 36 (34) 18 (17) 22 (21) 0 (0)
Pre insertion, assembly of the SAM IO components
was easy. 3 (3) 12 (11) 15 (14) 31 (29) 45 (42)
Post insertion, removal of the SAM IO stylet from the
hub was easy. 6 (6) 11 (10) 11 (10) 42 (40) 36 (34)
I am confident using the SAM IO successfully in my 8 (8) 4 (4) 9 (8) 37 (35) 48 (45)
EMS practice.
The ability to use [hub adapter] either the SAM IO
needle or the EZ-IO needle with SAM driver would 16 (15) 12 (11) 52 (49) 13 (12) 13 (12)
influence my decision for preference.

the preparation and stabilization procedures, as in Kay et al., FIGURE 3 Needle assembly comparison.
which could be heavily influenced by clinician procedure fa-
miliarity and personal technique.

Although the disparities in insertion times were statistically
significant, the observed difference was less than 2s, which is
unlikely to translate into any clinically meaningful effect in re-
al-world field or hospital use. The drivers did exhibit a signif-
icant impact on the insertion results. This main effect factor
accounted for 41% of the observed variations in outcomes,
suggesting the drivers played a significant role in influencing
the other independent variables (needle sizes). It also explained
the insignificant results between needle sizes despite an intui- the SAM IO stylet was reported to be easy, as the stylet pulled
tive shorter needle time for the 15mm needle versus the 45mm straight from the needle assembly, unlike the counterclockwise
needle. Moreover, the study design intentionally differenti- screwing motion required to extract the EZ-IO stylet from
ated from the potential of a lack of familiarity with the newer its needle assembly (see Figure 4). Despite the ease of pulling
SAM IO device while focusing on insertion times between the straight back, more than a quarter of the participants found
battery-driven EZ-IO driver versus the manually powered “ac- the change in procedure less easy than their counterparts.
tuated” driver-assisted SAM IO driver. Nine extreme outliers FIGURE 4 Factorial ANOVA mean for insertion time by IO needle
greater than three SD were removed for procedural difficulties, size and driver.
such as delaying the removal of the stylet or self-declaring com-
pletion, which was observed and noted by the researcher. These
removals amounted to less than a 1s increase in the SAM IO
mean times, improving homogeneity and better representing
user performance. No product failures occurred.
The survey focused on the SAM IO devices’ contrasts, revealing
users’ mixed perceptions. Most respondents found the SAM
IO easy to use, suggesting a generally positive user experience.
However, opinions were divided, with just over half of the
participants disagreeing that the SAM IO had a better tactile
feel compared to the EZ-IO, and almost a third had a neutral
opinion. The authors feel that most participants experienced
no discernible difference in tactile feel between the powered
and manual drivers simply due to the lack of training time and
familiarity with the manual driver. The manual driver required
repetitive squeezing to actuate the motion, and about a quarter
of participants found this new procedure challenging. Despite SAM IO being a new device with only one training
session, four out of five participants felt confident using the
Assembly of the SAM IO needle into the driver was widely device in their EMS setting. Lastly, the availability of a hub
perceived as “easy.” However, 15 participants were challenged adapter to use either the EZ-IO or SAM IO needles on the
by the hexagonal shape of the needle hub and driver shaft SAM IO driver seemed to be a factor of preference for the
requiring a rotating motion dissimilar to the EZ-IO’s square SAM IO, with nearly half of the responses neutral (neither
hub and shaft (see Figure 3). The post-insertion removal of agreeing nor disagreeing) as a deciding factor.

SAM IO versus EZ-IO: Insertion Time and Usability | 37