Chang-Patel et al.
Effect of TAP Block Timing in Patients Undergoing MIH
Table 1
Demographic characteristics of the study population, stratified by TAP block administration and timing
Characteristic
n (%)
Age (years), mean ± SD
Body mass index (kg/m²), mean ± SD
Race, n (%)
No TAP block
Preoperative TAP block
n = 1966 (65.9)
n = 854 (28.6)
Postoperative TAP block
n = 162 (5.4)
p-value
42.9
10.3
30.6 ± 7.9
47.3 ± 11.8
30.88.0
Asian
69 (3.5)
17 (2.0)
Black
64 (3.3)
9 (1.1)
49.0 ± 12.3
31.88.7
4 (2.5)
0 (0.0)
<.001*
.164*
.004'
Hispanic
141 (7.2)
56 (6.6)
13 (8.0)
Other
48 (2.4)
19 (2.2)
5 (3.1)
White
1628 (82.8)
741 (86.8)
140 (86.4)
Not reported
16 (0.8)
12 (1.4)
0 (0.0)
<.001'
ASA physical status, n (%)
1
201 (10.2)
83 (9.7)
11 (6.8)
2
3
4
1449 (73.7)
522 (61.1)
111 (68.5)
313 (15.9)
244 (28.6)
40 (24.7)
1 (0.1)
5 (0.6)
Not reported
Procedure duration (minutes), mean ± SD
Endometriosis diagnosis, n (%)
1092 (55.4)
ASA = American Society of Anesthesiologists; TAP = transversus abdominis plane.
* ANOVA.
+ Chi-squared test.
110.3 ± 45.1
478 (56.0)
2 (0.1)
0 (0.0)
119.6 51.3
0 (0.0)
0 (0.0)
126.7 ± 43.1
91 (56.2)
<.001*
.957+
3
disease included in the study. Of these, 1932 (64.9%)
patients underwent a robotic-assisted total laparoscopic
hysterectomy, and 1046 (35.1%) underwent a total laparo-
scopic hysterectomy.
Patients were divided and analyzed into 3 groups: 1966
patients with no TAP block (65.9%), 854 with preoperative
TAP block (28.6%), and 162 with postoperative TAP block
(5.4%). Age, race, ASA physical status, and procedure
duration in minutes differed significantly across the 3
groups (Table 1). Patients who received a TAP block post-
operatively were older and had longer procedure times than
those who did not receive a TAP block or those who
received it preoperatively. Additionally, patients who
received a TAP block at any time point tended to more
often be of ASA physical status 3.
TAP block characteristics across all groups are shown in
Table 2. Ropivacaine was used in 453 patients (44.6%),
bupivacaine was used in 408 patients (40.2%), and 155
patients (15.3%) did not have data on the medication used.
The majority of TAP blocks were completed with ultra-
sound guidance (848; 83.5%), while the remainder used
landmark guidance (142;14%), nerve stimulation (5; 0.5%),
or not reported (21; 2.1%). All patients received opioids
intraoperatively and postoperatively. The majority of
patients received oxycodone (67.2%), fentanyl (52.7%),
and hydromorphone (51.7%) during the surgical encounter.
Patients who received either a preoperative or postopera-
tive TAP block used statistically significantly fewer millie-
quivalents of opioids (MME) postoperatively compared to
those who did not receive a TAP block (median 30.5 vs
38.5, p = .002) (Table 3). This difference is slightly more
than 5 mg of oxycodone, which is 7.5 MME. There was no
significant difference in MME use when comparing preop-
erative to postoperative TAP block recipients. TAP block
administration, regardless of timing, was associated with a
significantly shorter time to discharge than no TAP block
(median 5.5 vs 6.3 hours, p < .001), as was preoperative
compared to postoperative TAP block timing (median
5.3 vs 6.2 hours, p = .001). There were no statistically sig-
nificant differences between nausea medication administra-
tions, maximum postoperative pain score, or minutes to
maximum pain score. While not statistically significant,
Table 2
Characteristics of transversus abdominis plane (TAP) blocks
Characteristics
TAP Block Anesthetic used Bupivacaine
Ropivacaine
Not reported
Method
Ultrasound-guided
Landmark-guided
Nerve stimulation
Not reported
Complications
None
Present
Not reported
n (%)
408 (40.2)
453 (44.6)
155 (15.3)
848 (83.5)
142 (14.0)
5 (0.5)
21 (2.1)
774 (76.2)
1 (0.1)
241 (23.7)