Our results showed that compared with single-shot T-QLB alone, the combination of T-QLB and FICB could reduce sufentanil consumption by 36% at 24 h postoperative, significantly decrease the pain score, increase the early postoperative range of motion and improve the early quality of recovery, but does not increase the complications.
Accumulating published data[14, 15, 16, 19] were dedicated to exploring more effective multimodal analgesia with opioid-sparing. However, hip innervation is complex, with contributions from many nerve components[5]. Birnbaum[22] et al. reported that the nerves involved in THA's incision pain mainly including the subcostal nerve, iliohypogastric nerve, ilioinguinal nerve, femoral nerve, lateral femoral cutaneous nerve, obturator nerve, and sciatic nerve. Additionally, the latest study[23] indicated that the femoral nerve, dominating the hip joint, branches at a higher position. And the location of the lateral femoral cutaneous nerve under the inguinal ligament has significant anatomical variability[16, 23]. Therefore, performing single-shot peripheral nerve blocks, such as lumbar plexus, sacral plexus, fascia iliaca block, and quadratus lumborum block, is challenging to meet the patients' requirements. On the other hand, the lumbar plexus block has a high potential of hematoma and nerve injury because the needle tip should be advanced deeply and close to nerves[24]. Compared with the traditional peripheral nerve blocks(such as the lumbar plexus block), the fascial plane block technique, with higher safety, produces block analgesic effects mainly by local anesthetic along the fascia plane spreading to the corresponding nerves (nerve roots)[25].
Previous studies[14, 15, 16, 17] have shown that QLB and FICB can relieve postoperative pain after THA. In the group QF, better pain relief, and lower opioid requirements most likely contributed to the quality of recovery postoperatively than the group Q. The mechanism may be as follows: T-QLB provides pain relief over the incision area for patients undergoing THA, mainly through blockade of the T10-L3 nerve territories and dermatomal and inconsistent anesthetization of the obturator nerve[26]. Kadam[27] et al. found that the single-shot QLB can reduce pain scores and the demand for analgesic drugs 24 h postoperatively. Moreover, supra-inguinal FICB is accessed via a minimal risk approach to block the femoral nerve, lateral femoral cutaneous nerve, and obturator nerve, with rapid onset and definite analgesic effect, which procedure the anesthetization of the anterior, lateral, and medial areas of the thigh[17]. Wennberg[28] et al. reported that FICB effectively provided a high quality of pain relief after THA. Furthermore, although both sides seem to cover similar parts of the fields, T-QLB combined with FICB can optimize nerve block effects from block range and degree. And FICB can relieve patients’ pain when changing positions and ensure patients' comfort during the whole process.
Our results suggest that T-QLB combined with FICB can provide effective analgesia up to 18 h. The prolongation of analgesia time seems to exceed the expectation of 0.375% ropivacaine in peripheral nerve blockade[29]. Multiple reasons account for these results. Firstly, in our study, both QLB and FICB involved tissue (fascial) plane injections. The absorption rate of local anesthetics depends on the local tissue perfusion[25]. Murouchi[30] et al. reported that the peak concentration of ropivacaine after QLB is lower than that of TAPB at comparable time, and the duration of analgesia was significantly longer. Secondly, the group QF can further reduce the sensitivity of nerve to surgical stimulation, prevent central and peripheral sensitization, and reduce or eliminate pain caused by nociceptive stimulation[31]. Lastly, patients' oral paracetamol 1 g regularly at 6 h intervals after operation also prolonged time to the first opioid require.
The ability of NRS to reflect the effect of pain control is limited due to the application of multimodal analgesia. In our study, we observed that there was no significant difference in NRS between the two groups at 18 h after surgery. Taking postoperative sufentanil consumptions into account, we believed that the combination of T-QLB and FICB provides a more effective analgesic effect in control to group Q, which mainly maintains a low pain score by increasing sufentanil consumption. Additionally, we apply the Qor-15 scale (score from 0–10 in each term, where 0 = no existence, 10 = always exist. The higher the Qor-15 scale score, the better the recovery quality of patients) to evaluate recovery quality after surgery and anesthesia, including physiological comfort, physical independence, psychological support, emotion, and pain. This study shows a significant difference in Qor-15 scale score and ROM between the two groups at 24 h and 48 h, consistent with a significant reduction in sufentanil consumption. Therefore, it further confirmed that the blockade combination contributes to relieve postoperative pain, reduces postoperative anxiety, improves patient satisfaction and comfort, and optimizes early postoperative recovery quality.
All blocks were performed before anesthesia induction. Hydro-separation of the target interfascial plane with saline is beneficial to local anesthetic’s correct deposition and improves the block's success rate. Moreover, a professional investigator evaluated the analgesic effect 30 min after performing the nerve block to avoid potential block failure. In our study, three patients in group Q were excluded due to an ineffective block, which reduced the occurrence of selective bias.
It would be better for elderly patients with comorbidities to use an anesthetic with higher safety and longer half-life, such as ropivacaine[29]. In this study, 150 mg of ropivacaine is safe and effective for elderly patients. However, previous studies[15, 32] reported that complications such as hypotension and urinary retention were observed after performing QLB, which did not occur in our study. Future studies should focus on the minimal effective volume for proximal spreading and the dose-response relationship. Additionally, ropivacaine has the function of sensory-motor integration, it can block the sensory nerve while retaining the motor nerve function, which has significant advantages for the early recovery of postoperative patients[29]. Ueshima[33] et al. reported that the incidence of quadriceps weakness was about 65% after QLB. However, we did not quantify the nerve block effect on motor function (muscle strength), and the quantification of motor function is difficult. The postoperative motor function may be affected by the following factors: Firstly, the patients were afraid of exercise due to severe postoperative pain, especially in the group Q with poor pain control. Secondly, iatrogenic nerve injury is attributed to nerve compression by retractors and manipulating the hip[34]. Thirdly, transient nerve palsy can develop postoperatively as a result of a hematoma[34]. Therefore, it can be considered that the decrease in motor function postoperative is not entirely caused by the nerve block.