Characteristics of Study Population
In total, 178 patients were included in the study. The baseline demographic and surgical variables of patients are presented in Table 1. There were no significant differences in age, sex, body mass index (BMI), basic diseases, ASA grade, NYHA grade, total surgery time, total fluid volume, urine volume, total volume of allogeneic erythrocyte infusion or total volume of plasma (P>0.05). However, the time to tracheal catheter extraction was shorter in the GR group than in the G group (P<0.05). The total amount of both remifentanil and rocuronium used was less in the GR group than in the G group (P<0.05). Thus, posterior RSB could reduce the use of remifentanil and rocuronium during surgery.
Table 1 Demographic and surgical variables, mean±SD
|
G group (n=89)
|
GR group (n=89)
|
P value
|
Age (y)
|
46.1±8.2
|
45.3±8.0
|
0.512
|
Sex (male/female)
|
45/44
|
36/53
|
0.176
|
BMI (kg/m2, ±s)
|
24.92±2.40
|
24.43±1.77
|
0.123
|
Medical history
|
|
|
|
Diabetes mellitus (n)
|
27/62
|
25/64
|
0.742
|
Hypertension (n)
|
40/49
|
48/41
|
0.230
|
Coronary heart disease (n)
|
11/78
|
8/81
|
0.466
|
ASA grade I/II/III
|
32/50/7
|
36/43/10
|
0.524
|
NYHA grade I/II
|
59/30
|
50/39
|
0.166
|
Total surgery time (h,±s)
|
517.58±87.90
|
522.97±95.73
|
0.697
|
Time to tracheal catheter
extraction (min,±s)
|
49.48±5.07
|
37.45±3.89
|
<0.001
|
Remifentanil (mg,±s)
|
4.21±0.50
|
2.18±0.20
|
<0.001
|
Rocuronium (mg,±s)
|
101.97±10.85
|
84.26±9.99
|
<0.001
|
Total fluid volume (ml)
|
5491.36±587.99
|
5543.36±541.21
|
0.541
|
Urine volume (ml)
|
1310.56±161.35
|
1324.38±153.75
|
0.559
|
Total volume of allogeneic
erythrocyte infusion (ml)
|
319.55±235.82
|
329.21±243.18
|
0.788
|
Total volume of plasma (ml)
|
987.64±114.14
|
973.71±122.99
|
0.434
|
ASA, American Society of Anesthesiologists; BMI, body mass index (calculated as weight in kilograms divided by height in metres squared); NYHA, New York Heart Association; G, general anaesthesia; GR, bilateral rectus sheath block combined with general anaesthesia. Before bilateral rectus sheath block (T1), the time of anaesthesia (T2), the time of skin incision (T3), the time of peritoneal thermochemotherapy (T4), and the end of surgery (T5)
Changes in Haemodynamic Parameters
The changes in HR and MAP are presented in Table 2. There were no significant differences in HR or MAP at any point in time (T1 to T5) between the two groups (P>0.05). The results suggest that BRSB did not affect the haemodynamics of the patient undergoing CRS/HIPEC.
Table 2 Haemodynamic parameters in both groups, mean±SD
Index
|
Time point
|
G
|
GR
|
P value
|
(N=89)
|
(N=43)
|
MAP
(mmHg,±s)
|
T1
|
81.44±12.03
|
83.74±12.1
|
0.205
|
T2
|
76.54±7.84
|
77.91±8.29
|
0.259
|
T3
|
75.94±7.89
|
75.99±8.72
|
0.971
|
T4
|
81.05±9.02
|
80.82±9.89
|
0.874
|
T5
|
83.66±8.11
|
84.19±8.73
|
0.676
|
HR
(bpm, ±s)
|
T1
|
73.66±6.36
|
72.47±7.80
|
0.266
|
T2
|
76.72±6.24
|
76.29±7.39
|
0.678
|
T3
|
78.42±8.79
|
79.93±7.54
|
0.218
|
T4
|
78.17±8.25
|
79.00±10.66
|
0.561
|
T5
|
84.74±6.19
|
83.91±6.28
|
0.368
|
MAP, mean arterial pressure; HR, heart rate; G, general anaesthesia; GR, bilateral rectus sheath block combined with general anaesthesia.
Pain-related Indicators
Table 3 shows the postoperative VAS score, the PCA input dose and the number of PCA boluses at 1 h (T6), 6 h (T7), 12 h (T8), 24 h (T9) and 48 h (T10) after surgery, as well as the dose of dezocine used as a rescue analgesic. From T6 to T8, compared with the G group, the GR group showed significantly decreased VAS scores of pain at rest and during motion (P<0.05). However, at 24 h and 48 h after surgery, there were no significant differences in the VAS scores of pain at rest and during motion between the two groups (P>0.05). From T6 to T10, the PCIA input dose and the number of PCA boluses were also obviously reduced in the GR group compared with the G group (P<0.05). In addition, as a rescue analgesic, the dose of dezocine after surgery in the GR group was significantly lower than that in the G group (P<0.05).
Table 3 Pain-related indicators in both groups, median [range]
|
G
|
GR
|
P value
|
(N=89)
|
(N=89)
|
VAS score of pain at rest, [median (range)]
|
T6
|
6[3, 9]
|
4[3, 5]
|
<0.001
|
T7
|
5[3, 9]
|
4[3, 5]
|
<0.001
|
T8
|
3[3, 6]
|
3[1, 5]
|
0.001
|
T9
|
2[1, 3]
|
2[1, 4]
|
0.765
|
T10
|
2[1, 3]
|
2[1, 3]
|
0.314
|
VAS score of pain during motion [median (range)]
|
T6
|
7[4, 9]
|
5[3, 8]
|
<0.001
|
T7
|
6[4, 9]
|
4[3, 8]
|
<0.001
|
T8
|
4[3, 9]
|
4[2, 6]
|
<0.001
|
T9
|
3[1, 4]
|
3[1, 5]
|
0.922
|
T10
|
3[1, 4]
|
3[1, 5]
|
0.557
|
Total infused dose of PCIA [ml, median (range)]
|
T6
|
4[2, 7]
|
2[2, 4]
|
<0.001
|
T7
|
15[12, 19]
|
12[10, 17]
|
<0.001
|
T8
|
26[24, 30]
|
25[24, 27]
|
<0.001
|
T9
|
50[48, 54]
|
50[48, 54]
|
0.024
|
T10
|
100[96, 100]
|
97[96, 100]
|
<0.001
|
Cumulative number of PCIA boluses [median (range)]
|
T6
|
1[1, 2]
|
0[0, 1]
|
<0.001
|
T7
|
5[1, 8]
|
1[1, 2]
|
<0.001
|
T8
|
9[7, 13]
|
5[3, 8]
|
<0.001
|
T9
|
9[8, 15]
|
8[5, 15]
|
<0.001
|
T10
|
12[7, 17]
|
12[7, 17]
|
0.047
|
Total dose of dezocine as a rescue analgesic (mg, ±s)
|
6.07±5.08
|
15.90±4.10
|
<0.001
|
VAS, visual analogue scale; PCIA, patient-controlled intravenous analgesia; G, general anaesthesia; GR, bilateral rectus sheath block combined with general anaesthesia. The time at 1 h after surgery (T6); 6 h after surgery (T7); 12 h after surgery (T8); 24 h after surgery (T9); and 48 h after surgery (T10).
Postoperative Adverse Events
Adverse events that occurred in the SICU are presented in Table 4. After surgery, there were 29 cases with hypertension, 9 cases of emergence agitation, 7 cases of delayed recovery, 7 cases of hypercapnia, and 12 cases of nausea and vomiting in the G group; fewer cases of all of these events occurred in the GR group (P<0.05). There were no differences in the incidence of hypoxemia between the two groups (P>0.05). There were no complications associated with nerve block in either group.
Table 4 Postoperative adverse events in both groups
Adverse events
(n, %)
|
G
|
GR
|
P value
|
(N=89)
|
(N=43)
|
Hypertension
|
29(32.58%)
|
11(12.36%)
|
0.001
|
Emergence agitation
|
9(10.11%)
|
2(2.24%)
|
0.029
|
Delayed recovery
|
7(7.87%)
|
1(1.12%)
|
0.030
|
Hypoxemia
|
5(6.74%)
|
2(2.24%)
|
0.254
|
Hypercapnia
|
7(7.87%)
|
1(1.12%)
|
0.030
|
Nausea and vomiting
|
12(13.48%)
|
4(4.49%)
|
0.036
|
Peritoneal puncture
|
0(0%)
|
0(0%)
|
—
|
Internal organ injury
|
0(0%)
|
0(0%)
|
—
|
Systemic toxicity
|
0(0%)
|
0(0%)
|
—
|
G, general anaesthesia; GR, bilateral rectus sheath block combined with general anaesthesia.