Page 23 - JSOM Spring 2021

TABLE 2 Temperature Change From Inlet of Warmer to End of Outlet Tubing at All Test Conditions
RT NS SL RT NS 8K RT NS 16K Cold PRBC SL Cold PRBC 8K Cold PRBC 16K
Emergent Flow Rate
Time to reach mean temp at end of outlet tubing (sec)
Buddy Liter - powered 26 ± 19 20 ± 3 10 ± 2 151 ± 31 42 ± 27 119 ± 32 e
Buddy Liter - battery 30 ± 6 23 ± 3 ab 17 ± 16 108 ± 38 bde 37 ± 14 e 94 ± 28 cd
b
be
Buddy Lite AC - powered 60 ± 11 49 ± 17 36 ± 20 91 ± 23 58 ± 17 55 ± 7
Buddy Lite AC - battery 32 ± 15 e 33 ± 4 23 ± 2 bd 103 ±16 b 62 ± 20 48 ± 13 d
bcd
bc
Thermal Angel 47 ± 4 60 ± 13 58 ± 4 d 28 ± 13 de 25 ± 3 e 61 ± 34
M Warmer 34 ± 20 24 ± 3 ‡ 25 ± 2 bd 68 ± 31 d 25 ± 12 27 ± 7 de
Temp change from inlet to end of outlet tubing (°C)
Buddy Liter - powered 2.4 ± 0.3 e 2.0 ± 0.2 e 1.8 ± 0.1 9.0 ± 0.3 e 13.5 ± 0.9 e 11.3 ± 1.0
Buddy Liter - battery 1.6 ± 0.2 abce 1.5 ± 0.2 abce 1.4 ± 0.3 abce 6.5 ± 0.8 abce 9.5 ± 2.0 bce 9.7 ± 1.5 bc
Buddy Lite AC - powered 6.0 ± 0.3 4.7 ± 0.4 4.6 ± 0.6 18.0 ± 0.9 16.1 ± 1.6 8.6 ± 1.0
Buddy Lite AC - battery 4.5 ± 0.3 bcde 2.9 ± 0.7 bcde 3.0 ± 0.2 bce 15.0 ± 0.5 bcde 13.4 ± 2.0 10.1 ± 0.9
bc
Thermal Angel 7.9 ± 0.3 de 6.1 ± 0.4 de 6.7 ± 0.4 de 17.8 ± 0.8 d 15.0 ± 0.6 15.4 ± 0.3
de
M Warmer 12.7 ± 0.2 bde 10.1± 0.6 bde 9.9 ± 0.2 bde 24.5 ± 0.8 bde 22.5 ± 1.0 bde 21.8 ± 1.2
bde
Nonemergent Flow Rate
Time to reach mean temp at end of outlet tubing (sec)
Buddy Liter - powered 413 ± 71 246 ± 42 231 ± 45 252 ± 43 284 ± 43 296 ± 59
Buddy Liter - battery 252 ± 62 191 ± 38 270 ± 113 283 ± 48 281 ± 42 228 ± 90
d
Buddy Lite AC - powered 323 ± 59 207 ± 24 195 ± 65 273 ± 58 252 ± 81 336 ± 144
Buddy Lite AC - battery 206 ± 27 bcde 262 ± 105 235 ± 82 b 289 ± 25 237 ± 26 304 ± 37
Thermal Angel 244 ± 13 d 152 ± 29 d 133 ± 38 308 ± 61 324 ± 94 332 ± 55
M Warmer 251 ± 7 d 272 ± 66 b 259 ± 61 325 ± 99 345 ± 148 299 ± 155
Temp change from inlet to end of outlet tubing (°C)
Buddy Liter - powered 9.6 ± 0.1 6.0 ± 0.3 6.8 ± 0.4 8.7 ± 0.7 e 5.6 ± 0.3 e 6.0 ± 0.9
Buddy Liter - battery 10.2 ± 0.3 bd 5.9 ± 0.4 bc 6.9 ± 0.3 b 8.7 ± 0.7 be 5.1 ± 0.7 6.9 ± 0.4 abe
Buddy Lite AC - powered 9.6 ± 0.1 5.8 ± 0.2 6.9 ± 0.2 9.0 ± 0.6 4.6 ± 0.3 5.3 ± 0.4
Buddy Lite AC - battery 9.7 ± 1.1 6.3 ± 0.4 be 6.8 ± 0.6 b 8.7 ± 0.6 bd 5.5 ± 0.6 b 4.9 ± 0.1 c
Thermal Angel 8.5 ± 0.4 de 8.4 ± 0.5 de 8.5 ± 0.3 de 6.7 ± 0.2 de 4.3 ± 0.4 d 5.9 ± 0.9
M Warmer 10.3 ± 0.5 b 6.7 ± 0.7 6.4 ± 0.4 be 9.1 ± 0.6 b 5.2 ± 0.6 7.0 ± 0.9 be
Statistical significance (p < .5). Legend: vs Buddy Lite, vs Thermal Angel, vs M Warmer, vs Buddy Liter AC Power, vs Buddy Lite AC Power.
c
b
d
a
e
Figure 4 shows the percentage of time the devices produced Battery life and mean temperature varied widely among de-
temperatures ≥32°C at all conditions on battery power. As vices under the extremes of conditions. All differences were
shown, the percentage of time the M Warmer produced fluid statistically significant (p < .001) except mean temperatures
temperatures that reached this threshold was significantly using the nonemergent flow (p = .5). Using the nonemergent
higher than for the other devices using NS and PRBCs at the flow, mean battery life differed widely between all devices
emergent flow, at all altitudes. The Buddy Liter and Buddy (774.9 ± 256.9 minutes). Mean temperatures were 33.7 ±
Lite failed to produce temperatures that reached this thresh- 1.0°C between all devices but were not statistically significant
old at any altitude. At ground level using NS at the none- or clinically important. The Buddy Lite had the longest battery
mergent rate, all the devices reached this threshold >90% of life under this condition. Mean battery life differed widely be-
the time. At this condition, percentages above this threshold tween all devices (35.0 ± 28.6 minutes) as did mean tempera-
were significantly less for all devices at 8,000 ft and 16,000 tures (19.9 ± 7.3°C) when using the emergent flow. The Buddy
ft except for the Thermal Angel at 8,000 ft (97%). At ground Liter had the longest battery life under this condition. Table 3
level using PRBCs at the nonemergent flow, all devices except shows the mean battery life and mean temperature with each
the Thermal Angel reached the ≥32°C threshold >90% of the device at both conditions.
time. At 8,000 ft and 16,000 ft, the percentage of time at the
threshold was less. Discussion

The Buddy Liter and Buddy Lite were the only two devices This study showed there were large differences in the tempera-
that had the capability to use AC power in addition to battery ture profiles between devices on battery power using emergent
power, so these data were analyzed separately. Nearly all the flow with both NS and PRBCs. There were also differences
differences in changes in temperature between these two de- among devices using nonemergent flow, although they were
vices were statistically significant and less than half of the time much smaller (Figure 2). The M Warmer produced the highest
to mean temperature differences were significant. The major- mean temperature at all conditions. The change in tempera-
ity of the significant differences were when comparing ground ture from the inlet of the warmers to the end of the outlet
level to 16,000-ft altitude (Figure 3). extension tubing was used to determine the devices heating

Fluid Warming Technology Performance | 21