Bilateral Erector Spinae Plane Blocks for Open Posterior Lumbar Surgery

Figures & data

Figure 1 The Consolidated Standards of Reporting Trials (CONSORT) flow diagram of the study. ESPB, erector spinae plane block.

Figure 2 Longitudinal parasagittal ultrasound view (A) and extent of cutaneous sensory loss over the back at 40 minutes after the injection of 25 mL of 0.3% ropivacaine in one patient at the T12 level (B). Arrows represent the spread of local anesthetic. TP, transverse process; ESM, erector spinae muscle; LA, local anesthetic.

Table 1 Baseline Demographic and Clinical Characteristics of Study Participants

Characteristic	T12 Group (n=30)	Control Group (n=30)	Total (n=60)
Age (yr.)	64 (9.4)	64 (10.3)	63 ± 10.4
Gender (female/male)	17/13	22/8	39/21
Height (cm)	163 (6.9)	163 (7.3)	164 ± 7.8
Weight (kg)	67 (9.4)	66 (9.3)	67 ± 9.4
ASA classification (I/II/III)	6/22/2	7/19/4	13/41/6
Past medical history
Hypertension	15	16	31
Diabetes	5	6	11
Coronary heart disease	5	4	9
Cerebral infarction	2	1	3
Hemiplegia	0	0	0
Smoking history	6	8	14
Drinking history	10	6	16
NRS pain score at rest	3.9 (1.9)	4.0 (1.5)	4.0 ± 1.6
NRS pain score at movement	6.0 (1.8)	5.5 (1.6)	5.8 ± 1.6
MAP (mmHg)	104 (10.2)	99 (8.3)	102 ± 9.7
Heart rate (beat/min)	68 (8.1)	70 (8.9)	70 ± 8.5
Surgical segment (L3/L4/L5)	16/29/28	23/30/29	39/59/57

Note: Data are presented as mean (SD) or number.

Abbreviations: ASA, American Society of Anesthesiologists; NRS, numerical rating scale; MAP, mean arterial pressure.

Figure 3 (A) The primary outcome of the MOAA/S score was assessed every 10 minutes, from 10 to 30 minutes after extubation in patients receiving T12 ESPB (orange) or no block (grey) undergoing posterior lumbar surgery. (B) The postoperative cumulative morphine consumption (mg) at 24 and 48 hours in patients receiving T12 ESPB (orange) or no block (grey). (A) n = 30 for all groups; (B) n = 28 for all groups. Repeated measures two-way ANOVA + Bonferroni. *P < 0.05. Data are presented as mean (SD).

Abbreviations: MOAA/S, Modified Observer’s Assessment of Alertness/Sedation; ERAS, enhanced recovery after surgery; ESPB, erector spinae plane block; MOAA/S, Modified Observer’s Assessment of Alertness/Sedation; ASA, American Society of Anesthesiologists; NRS, numerical rating scale; MAP, mean arterial pressure; PACU, post-anesthesia care unit; PCIA, patient-controlled intravenous analgesia; TP, transverse process; ESM, erector spinae muscle; LA, local anesthetic.

Table 2 Intraoperative Outcomes

		T12 Group (n=30)	Control (n=30)	P value
Duration of anesthesia (min)		190 (57)	207 (58)	0.486
Sufentanil dosage (ug)		20 (7.0)	25 (5.6)	0.007
Pre-incision	MAP (mmHg)	83 (7.5)	90 (11.1)	0.025
	Heart rate (beat/min)	58 (7.2)	61 (7.5)	0.173
5 min after incision	MAP (mmHg)	84 (9.5)	93 (10.9)	0.002
	Heart rate (beat/min)	57 (7.4)	66 (9.0)	<0.001
End of surgery	MAP (mmHg)	87 (6.7)	91 (9.3)	0.409
	Heart rate (beat/min)	61 (7.0)	67 (10.1)	0.014
PaCO2 at 20 min after extubation (mmHg)		46 (5.2)	48 (5.9)	0.135
Duration of anesthesia recovery(min)		35 (1.5)	45 (4.6)	<0.001

Note: Data are presented as mean (SD).

Abbreviation: MAP, mean arterial pressure.

Table 3 Follow-Up Outcomes

		T12 Group (n=30) ^#	Control (n=30)	P value
First time of morphine bolus (h)		9.5 (6–15.5)	1.0 (0.5–6.5)	<0.001
24 hours after surgery outcomes	NRS pain score at rest	1.5 (1.1)	2.1 (1.5)	0.158
	NRS pain score at movement	2.9 (1.4)	3.7 (1.9)	0.174
	Effective bolus times	3.0 (2.0)	15.5 (3.2)	0.008
48 hours after surgery outcomes	NRS pain score at rest	0.9 (0.7)	1.6 (1.3)	0.066
	NRS pain score at movement	2.0 (0.9)	3.0 (1.6)	0.052
	Effective bolus times	5.3 (3.2)	22.5 (5.7)	0.001
First time to ambulation after surgery (h)		72 (72–96)	96 (78–111)	0.003
Hospital length of stay after surgery (d)		6 (5–9.3)	6.5 (6–11.3)	0.054

Notes: Data are presented as median (Q1-Q3) or mean (SD). ^#For effective bolus times, n = 28 for all groups.