Page 42 - JSOM Winter 2017

Table 2 Discomfort Ratings Associated With Tourniquet Applications Figure 2 Occlusion and Completion Pressures.
Discomfort Rating, No.
Tourniquets None Little Moderate Severe
Distal singles (n = 150) 42 95 13 0
Proximal singles (n = 30 each location), cm
0 4 18 8 0
2 6 18 6 0
4 6 16 8 0
8 7 19 4 0
12 7 18 5 0
Pairs (n = 30 each pair), cm
0 12 18 0 0
2 15 15 0 0
4 11 18 1 0
8 13 14 3 0
12 9 15 6 0
Application sets (n = 120 each set)
First 39 59 22 0
Second 43 61 16 0
Third 32 76 12 0 (A)
Fourth 38 74 8 0
Fifth 40 74 6 0
Paired tourniquets had the lowest discomfort ratings (p = .088 versus
single distal tourniquets; p < .0001 versus single proximal tourniquets).
Single distal tourniquets had lower discomfort ratings than single prox-
imal tourniquets (p = .0084). There was a trend for increasing discom-
fort with increasingly proximal placements in paired tourniquets (p =
.049), but no such trend occurred with single proximal tourniquets
(p = .91). The second leg did not have lower discomfort ratings than the
first leg, but a trend for decreasing discomfort occurred with increasing
leg application sets (p = .0185, right and left leg combined).

Pressure/Tooth Advance
Fewer tooth advances per tourniquet but more total per ap-
plication were required with pairs: distal of pair 5 ± 1, proxi-
mal of pair 4 ± 1, single distal 6 ± 1, single proximal 6 ± 1;
p < .0001. The increase in pressure/tooth advance was visually
least for the first tooth advance and increased with increasing
tooth advances. The clearly definable single tooth advance for
every application was from occlusion pressure to completion
pressure (Figure 3). The pressure increases for the final tooth
advances were least in pairs with progressively less within pair
interaction as distance increased. Among single tourniquets,
the pressure increases for the final tooth advances were lowest (B)
with the most proximal tourniquet involvement.
Each symbol indicates the pressure under an individual tourniquet
on a single subject. Black dots indicate pressures under distal tour-
Occlusion Maintenance niquets. Green rectangles indicate pressures under tourniquets 0cm
Tourniquet pressures decreased over time, and some tourni- proximal from the distal location. Blue upward triangles indicate
quet applications failed to maintain occlusion. As shown in pressures under tourniquets 2cm proximal from the distal location.
Figure 4, failure to maintain occlusion for 120 seconds oc- Purple downward triangles indicate pressure under tourniquets 4cm
curred most frequently with pairs and occurred earlier and in from the distal location. Orange diamonds indicate pressure under
an increasing frequency with increasingly proximal singles. tourniquets 8cm from the distal location. Red hexagons indicate
pressures under tourniquets 12cm from the distal location. In paired
Within paired and single tourniquet applications, neither oc- applications, lines connect the pressure from each discrete distal
clusion pressure, completion pressure, 120-second pressure, tourniquet to that of its respective proximal tourniquet. (A) Occlu-
nor the difference between occlusion pressure and 120-second sion pressures. Occlusion pressures were lower for each individual
pressure or completion pressure and 120-second pressure dif- pair tourniquet than each respective single, higher for each pair dis-
ferentiated between tourniquet applications that maintained tal than respective pair proximal, and higher for each single distal
than respective single proximal (all p < .0001). Occlusion pressures
versus lost occlusion (Figure 5). Among paired tourniquet were lower with proximal tourniquet involvement (pair or single, p <
applications, however, having the last tooth advance occur .0001). (B) Completion pressures. Completion pressures were lower
on the distal tourniquet was associated with fewer occlusion for each individual pair tourniquet than each respective single, higher
losses (maintained occlusion: distal last advance 61, proximal for each pair distal than respective pair proximal, and higher for each
single distal than respective single proximal (all p < .0001). Comple-
last advance 63; lost occlusion: distal last advance 2, proximal tion pressures were lower with proximal tourniquet involvement
last advance 24; p < .0001). (pair or single, p < .0001).

40 | JSOM Volume 17, Edition 4/Winter 2017