Ultrasound-Guided Suprainguinal Fascia Iliaca Compartment Block for Postoperative Analgesia in Patients Undergoing Hip and Femur Surgeries: A Retrospective Analysis.

CONTEXT: Fractures of femur and hip surgeries pose a challenge because of excruciating pain. Fascia iliaca compartment block is an effective and easily learned procedure to decrease postoperative pain score and dosage of opioid. Many adjuvants are combined with local anesthetics to prolong the postoperative analgesia. AIMS: The aim was to study duration of postoperative analgesia in terms of Numeric Rating Scale (NRS), number of times rescue analgesic used, any adverse effect, and patient satisfaction score. SETTINGS AND
DESIGN: Operation theatre of Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow.
MATERIALS AND METHODS: The present study was retrospective study with 203 patients evaluated. Based on the combination of the anesthesia and drugs, study patients were divided into six groups. Pain scores were assessed at 6 hourly intervals for 24 h. STATISTICAL ANALYSIS USED: Kruskal-Wallis H-test used to compare NRS as well as age and duration of anesthesia. Chi-square test/Fisher's exact test used to compare the proportions.
RESULTS: Postoperative analgesia was comparable and insignificant (P > 0.05) at 0, 6, 12 h in all six groups. Better postoperative analgesia was observed with dexmedetomidine and dexamethasone as adjuvant at 18 h, dexmedetomidine as adjuvant in comparison to dexamethasone as adjuvant at 24 h. Rescue analgesia in postoperative period was required maximum in plain bupivacaine. Satisfaction levels were good and excellent in dexmedetomidine and dexamethasone as adjuvant.
CONCLUSIONS: Addition of dexmedetomidine to bupivacaine provides longer duration, good quality postoperative analgesia, reduced requirement for rescue analgesic, lesser postoperative nausea and vomiting, and better satisfaction levels. Copyright:

INTRODUCTION

Femur and hip surgeries are known to be associated with moderate-to-severe postoperative pain for the first 24–48 h which may adversely affect early mobilization and physiotherapy eventually affecting rehabilitation of the patient. Postoperative pain is primarily due to extensive bony and soft-tissue damage. Postoperative pain management usually involves multimodal analgesia including both systemic and regional analgesia. Systemic analgesia involves oral, parenteral, or transdermal administration of opioids, nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol. Regional analgesia involves intra-articular injection of local anesthetic (LA) or opioid, neuraxial analgesia, and peripheral nerve blocks.

Systemic analgesia is known to be associated with undesirable side-effects, particularly undesirable in patients with advanced age and comorbid conditions. Opioids may cause respiratory depression, itching, hypotension, dizziness, constipation, urinary retention, mental confusion, and nausea.[1] NSAIDs may affect renal function and cause gastrointestinal hemorrhage. Peripheral nerve blocks such as femoral nerve (FN) block, Winnie's 3-in-1 FN block, pericapsular nerve group block and fascia iliaca compartment block (FICB) have been used to provide postoperative analgesia and have shown opioid-sparing effects.[234]

FICB is a commonly employed technique by anesthetists and emergency physicians using landmark-based technique for infra-inguinal approach (FICB-I) to provide on arrival analgesia for fracture femur and hip.[5] FICB is an effective and easily learned procedure to decrease postoperative pain score and dosage of opioid. Ultrasound (USG)-guided FICB-I has increased the success rate to 82%–87%, which led to an increased interest in FICB as a postoperative analgesia option for hip and femur surgeries.[6]

Majority of studies which evaluated FICB in fracture hip and femur patients, were FICB-I done either using landmark based double pop technique or were USG guided. This approach did not result in reliable blockade of lateral femoral cutaneous nerve (LFCN) and obturator nerve. USG-guided supra-inguinal approach of FICB (FICB-S), with LA injection superficial to the iliacus muscle (IM), superior to the inguinal ligament, will block both FN and LFCN.[7] Vermeylen et al. demonstrated that FICB-S achieved complete sensory block of the medial, anterior and lateral region of the thigh in 80% of the volunteers compared with 30% after FICB-I. Reason for greater success in FICB-S is because of LFCN having a more consistent course above the inguinal ligament superficial to IM and immediately deep to the fascia iliaca (FI) in the pelvis.[8]

Postoperative analgesia provided by FICB can persist up to 24 h. Adjuvants such as epinephrine, clonidine, opioids, ketamine, dexamethasone, and dexmedetomidine have demonstrated efficacy in prolonging postoperative analgesia in various peripheral nerve blocks. This study is a retrospective analysis of USG-guided FICB-S for postoperative analgesia in patients undergoing hip and femur surgeries in level 1 trauma centre.

Aims and objectives

The aim was to study FICB-S in hip and femur surgeries with regard to:

Primary aim

Duration of postoperative analgesia in terms of Numeric Rating Scale (NRS)

Secondary aim

Number of times rescue analgesic was administered

Any adverse effect (postoperative nausea and vomiting [PONV], hypotension, bradycardia)

Patient satisfaction score.

MATERIALS AND METHODS

After clearance was obtained from the Institutional Ethics Committee (IEC code-2020-260-IP-EXP-29, dated-13/8/2020), data were analyzed for patients undergoing hip and femur surgery between October 2018 to March 2020. Patient consent was waiver of by the Institutional Ethics Committee as this study was retrospective. Preoperative data included age, gender, the American Society of Anesthesiologists (ASA) status, diagnosis, and surgery. Intraoperative data included duration of anesthesia, anesthesia technique, type, volume and concentration of LA, any adjuvant used. Postoperative data included postoperative pain assessment scores. Confidentiality of data and privacy of research participant was maintained.

Patients included in study included those above 18 years of age, of either sex weighing above 50 kg, ASA physical status I and II and operated for hip and femur surgeries. Patients with incomplete medical record, epidural anesthesia, no block, FICB-I, FICB-S with landmark approach, patients on chronic opioids and those of ASA physical status III and IV were excluded from the study. A flow chart demonstrating patient selection is presented in Figure 1.

Figure 1

Flow chart demonstrating patient selection

Postoperative pain assessment as mandated by department's protocol involved use of Numerical Rating scale (NRS); 0 = no pain, 10 = worst imaginable pain. Pain was assessed on arrival in post anesthesia care unit (PACU) and thereafter at 6 hourly for 24 h. Injection paracetamol 1 g was administered intravenous (i.v.) 8 hourly as part of multimodal analgesia. NRS > 4 was treated as breakthrough pain and Injection Tramadol 100 mg was given as rescue analgesic. Patient satisfaction score with respect to postoperative analgesia was enquired after 24 h and was labeled as excellent, good, fair, and poor.

Ultrasound-guided fascia iliaca compartment block-S

Linear high frequency (13-6 MHz) USG transducer was positioned longitudinally at the level of the anterior superior iliac spine (ASIS) in a patient lying supine. By sliding the USG transducer in a medial and caudal direction, the IM and FI was identified. To obtain a “bow-tie sign” the transducer was rotated slightly so that the cranial end of the transducer points to the umbilicus and the caudal end pointed at the ASIS. Injection with 40 ml of LA was considered successful if hydro-dissection between the FI and the IM occurred and if cranial spread of LA under the FI was present. Repositioning of the needle was allowed during the injection to achieve “adequate” spread.

Statistical analysis

Continuous variable is presented in mean ± standard deviation whereas discrete and ordinal variables in Median (IQR). Categorical variable is presented in frequency and percentage. Kruskal–Wallis H-test used to compare NRS as well as age and duration of anesthesia. Chi-square test/Fisher's exact test used to compare the proportions. P < 0.05 was considered as statistically significant. Statistical package for social sciences, Version 23 (SPSS 23, IBM, Chicago, USA) and Med Calc software was used for data analysis.

RESULTS

A total of 203 patients were found eligible and included in the study. Of these, 84.2% (n = 171) received SAB + FICB whereas 15.8% (n = 32) received GA + FICB. Mean and median age of the surgical patients were 41.91 and 36 years respectively (Range: 18–89 years) of which maximum were males (n = 146, 71.9%) [Table 1]. Data analysis revealed that 40 ml of drug was used with either no adjuvant or dexmedetomidine/dexamethasone were used as adjuvant.

Table 1

Distribution of the demographic and other variables among the patients

Variable´s	Mean	Median	Q1	Q3	Minimum	Maximum
Age	41.92	36.00	26.00	56.00	18.00	89.00
Sex (male)*	146 (71.9%)
Diagnosis*
Fracture neck of femur (%)	49 (24.1)
Intertrochanteric fracture (%)	43 (21.2)
Subtrochanteric fracture (%)	12 (5.9)
Proximal femur fracture (%)	15 (7.4)
Fracture shaft of femur (%)	56 (27.6)
Distal femur fracture (%)	22 (10.8)
Acetabular fracture (%)	6 (2.9)
Duration of anesthesia (h)	3.24	3.00	2.50	4.00	1.00	7.00
NRS 0 h	2.56	2.00	2.00	3.00	1.00	8.00
NRS 6 h	2.73	2.00	2.00	3.00	1.00	8.00
NRS 12 h	2.49	2.00	2.00	3.00	1.00	6.00
NRS 18 h	2.58	2.00	2.00	3.00	1.00	7.00
NRS 24 h	2.91	3.00	2.00	4.00	1.00	5.00
Rescue analgesia*	1.33	1.00	1.00	2.00	0.00	3.00
0 (%)	43 (21.2)
1 (%)	80 (39.4)
2 (%)	50 (24.6)
3 (%)	30 (14.8)

*Data are presented in frequency (%). NRS: Numeric rating scale

Based on the combination of the type of anesthesia administered and adjuvant used, study patients were divided into six groups:

Group 1-SAB + FICB (0.25% bupivacaine)

Group 2-SAB + FICB (0.25% bupivacaine + 1 μg. kg−1 of dexmedetomidine)

Group 3-SAB + FICB (0.25% bupivacaine + 4 mg of dexamethasone)

Group 4-GA + FICB (0.25% bupivacaine)

Group 5-GA + FICB (0.25% bupivacaine + 1 μg. kg−1 of dexmedetomidine)

Group 6-GA + FICB (0.25% bupivacaine + 4 mg of dexamethasone).

Based on these six groups further association between these patients were assessed with NRS at five time points, PONV, Satisfaction level at 24 h and number of times rescue analgesia was administered.

Demographical variables (Age, Sex) and duration of anesthesia were comparable in all 6 groups and were insignificant (P > 0.05). Postoperative analgesia was comparable and insignificant (P > 0.05) at 0, 6, 12 h in all 6 groups. Postoperative analgesia was observed to be better with dexmedetomidine and dexamethasone as adjuvant (Groups 2, 3, 5, and 6) in comparison to plain bupivacaine (Groups1 and 4) at 18 h. Better postoperative analgesia was observed with dexmedetomidine as adjuvant (Groups 2 and 5) in comparison to dexamethasone as adjuvant (Group 3) and plain bupivacaine (Groups 1, 4) at 24 h. Need for rescue analgesia was observed to be maximum with plain bupivacaine (Groups 1, 4) compared with dexmedetomidine and dexamethasone as adjuvant (Groups 2, 3, 5, 6). Satisfaction levels were good and excellent in dexmedetomidine and dexamethasone as adjuvant, respectively (Groups 2, 3, 5) in comparison to plain bupivacaine (Groups 1, 4). PONV was observed less in dexmedetomidine as adjuvant (Group 2, 5) in comparison to dexamethasone as adjuvant (Group 3) and plain bupivacaine (Groups1, 4). No adverse event was noted in postoperative period in the form of bradycardia, hypotension in any of the six groups [Table 2].

Table 2

Distribution of the demographic and other variables among the group

Variable´s	Group 1 (n=81)	Group 2 (n=71)	Group 3 (n=19)	Group 4 (n=19)	Group 5 (n=11)	Group 6 (n=2)	P
Age (median)	35 (26-56)	40 (28-60)	32 (24-61)	42 (24-58)	34 (28-50)	39	0.763†
Sex (male), n (%)	57 (70.4)	52 (73.2)	14 (73.7)	14 (73.7)	8 (72.7)	1 (50)	0.995*
Duration of anaesthesia (h)	3 (2-4)	3 (2-4)	3 (2-4)	3 (2-4)	3 (1-4)	3	0.351†
NRS, median (IQR)
0 h	2 (2-3)	2 (2-3)	2 (2-3)	2 (2-3)	2 (2-3)	1	0.224†
6 h	2 (2-3)	2 (1-3)	3 (2-3)	3 (2-3)	2 (2-4)	3	0.138†
12 h	2 (2-3)	2 (2-3)	2 (2-3)	2 (2-3)	2 (2-3)	3	0.912†
18 h	3 (2-3)	2 (2-3)	2 (2-2)	3 (2-3)	2 (1-3)	1	<0.001†
24 h	3 (3-4)	2 (2-3)	3 (2-3)	3 (3-4)	2 (2-2)	3	<0.001†
Rescue analgesia, n (%)
0	7 (8.6)	28 (39.4)	3 (15.8)	3 (15.8)	2 (18.2)	0	0.022*
1	28 (34.6)	32 (45.1)	8 (42.1)	4 (21.1)	6 (54.5)	2 (100)	0.093*
2	29 (35.8)	6 (8.5)	8 (42.1)	5 (26.3)	2 (18.2)	0	0.039*
3	17 (21)	5 (7.0)	0	7 (36.8)	1 (9.1)	0	0.22*
PONV	32 (39.5)	10 (14.1)	6 (31.6)	8 (42.1)	2 (18.2)	1 (50)	0.006*
Satisfaction level, n (%)
Poor	8 (9.9)	1 (1.4)	1 (5.3)	2 (10.5)	0	0	0.723
Fair	25 (30.9)	6 (8.5)	1 (5.3)	7 (36.8)	2 (18.2)	2 (100)	0.114
Good	38 (46.9)	26 (36.6)	14 (73.7)	6 (31.6)	6 (54.5)	0	0.027
Excellent	10 (12.3)	38 (53.5)	3 (15.8)	4 (21.1)	3 (27.3)	0	0.001

Significant level (P) computed between Group 1, 2, 3, 4, 5 only. Group 6 was not included due to small size (n=2) only, #Fisher’s exact test used, †Kruskal- Wallis H-test used. Multiple comparisons used for NRS, P<0.05 significant. At 18 h: Between Group 1 to Group 2, 3, 5 and Group 4 with Group 2, 3. At 24 h: Group 2 with Group 1, 3, 4 and Group 5 with Group 1, 4. IQR: Interquartile range, NRS: Numeric rating scale

DISCUSSION

The FI compartment is a potential space lying between the fascia iliaca anteriorly and the iliacus and psoas muscles (iliopsoas) posteriorly. Conventionally, the FICB was undertaken using a simple, landmark-guided approach but USG has renewed interest in FICB. USG has also facilitated the development of more proximal, suprainguinal approaches to the FICB. This is because successful blockade of LFCN and ON relies on proximal spread of LA as both of these nerves generally lie superior to the FI distal to the inguinal ligament. In a study using MRI to evaluate the spread of LA after USG infrainguinal FICB, the FN and LFCN were consistently blocked but there was no evidence of spread medially or cranially to reliably block the ON.[9] The USG-guided longitudinal approach to the FICB-S theoretically improves block success rates as the LA is injected more cranially allowing more consistent block of the three targeted nerves (FN, LFCN, and ON). Success rates of ON blockade and blockade of all three nerves were 86% and 67%, respectively, in an RCT comparing USG-guided FICB-S with placebo in patients undergoing total hip replacement.[10] Indeed, a recent cadaver study demonstrated that the FN, LFCN, and ON could be reliably blocked using an USG-guided FICB-S, but only if a volume of 40 ml was injected.[7]

Data analysis showed that the addition of dexmedetomidine to bupivacaine provided postoperative analgesia of longer duration, reduced requirement for rescue analgesics and better satisfaction levels in comparison with bupivacaine alone while administering FICB-S in hip and femur surgeries.

Good quality postoperative analgesia leads to improved patient satisfaction, enhanced functional recovery, earlier ambulation and initiation of physiotherapy, reduced incidence of deep vein thrombosis and reduced hospital stay. The use of regional anesthesia is an important component of opioid sparing multimodal analgesia strategy thereby precluding opioid use related adverse effects such as urinary retention, respiratory depression, pruritus, nausea, vomiting, sedation, constipation, altered mental status, and an increased incidence of falls.[11] Peripheral nerve blocks provide effective unilateral analgesia and unlike neuraxial analgesia is devoid of autonomic side effects, produces less motor blockade, and is associated with fewer neurological complications.[12]

Epinephrine, clonidine, opioids, ketamine, dexamethasone, and dexmedetomidine have been used as adjuvants to prolong the duration of postoperative analgesia. Dexmedetomidine, an α-2 agonists exerts its effect because of peripheral and central actions. Peripherally, it produces analgesia by reducing release of norepinephrine and causing α-2 receptor independent inhibitory effects on nerve fiber action potentials. Centrally, dexmedetomidine produces analgesia and sedation by inhibiting substance P release in the nociceptive pathway at the level of the dorsal root neuron and by activating α-2 adrenoceptors in the locus coeruleus.[1314] Therefore, the addition of dexmedetomidine as an adjuvant to bupivicaine for postoperative analgesia in FICB block prolonged the duration of block and improved its quality.

Dexamethasone has been shown to be effective as an adjuvant in few clinical studies. The decrease in pain intensity and the prolonged analgesia attained with the use of perineural dexamethasone may be the result of local or systemic action.[15] Locally, it may act on glucocorticoid receptors to induce vasoconstriction, thereby prolonging systemic absorption of LA. Another theory advocates that dexamethasone potentiates the activity of inhibitory potassium channels on nociceptive C fibers (via glucocorticoids receptors) thereby decreasing their activity. Systemically, it acts by reducing the inflammatory response caused by surgical tissue injury.

Sana et al. utilized landmark based FICB-I in patient undergoing fracture neck of femur surgery under spinal anesthesia. They demonstrated that addition of dexamethasone or dexmedetomidine to bupivacaine prolongs postoperative analgesia compared to plain bupivacaine. Moreover, addition of dexmedetomidine to bupivacaine provides better and prolonged postoperative analgesia than bupivacaine with dexamethasone.[16]

Kumar et al. demonstrated that FICB-I block duration was 1.5–2 times when dexamethasone was added as an adjuvant to plain bupivacaine (16.33 ± 5.69 h vs. 7.85 ± 1.62 h).[17]

Pillai et al. demonstrated efficacy of USG-guided FICB-S utilizing 30 ml ropivacaine with 50 mcg of dexmedetomidine as adjuvant in 50 patients undergoing hip arthroplasty. FICB-S as a component of multimodal analgesic regimen resulted in reduced opioid consumption and duration of analgesia for 18–24 h with minimal sedation and hemodynamic.[18] In addition, Krych et al. found that hip surgery patients experienced high overall satisfaction, high quality pain relief, and reduced consumption of opioids when using FICB-S.[19]

Sabra et al. observed that addition of dexmedetomidine to ropivacaine in FICB-S was efficacious in reducing severity of pain, in decreasing first 24 h total analgesic consumption, and prolonging the time for first request of analgesia in the postoperative period for patients undergoing hip arthroplasty.[20] Further Sivakumar et al. demonstrated that when compared to i.v. dexmedetomidine, perineural dexmedetomidine effectively prolongs the USG-guided FICB analgesic duration and reduces the 24 h postoperative morphine consumption in patients undergoing femur surgeries.[21]

Limitations of the study were as it was retrospective study; the main limitation of this study was the lack of well-described and standardized perioperative anesthesia and analgesia protocols as that of a prospective study. All blocks were performed by many anesthesiologist, which could be an issue when generalizing the results of this study. We have not included any control group or patients with no block and FICB-I for better comparison among groups.

CONCLUSIONS

Addition of dexmedetomidine to bupivicaine provides longer duration and good quality postoperative analgesia and reduced requirement for rescue analgesic in comparison with bupivicaine alone in FICB-S in the postoperative period in hip and femur surgeries.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.