Dexmedetomidine as an Adjuvant for Femoral Nerve Block and Functional Recovery After Total Knee Arthroplasty

Peking University First Hospital170 enrolled

Overview

Femoral nerve block (FNB) is a first-line analgesic technique for multimodal analgesia after total knee arthroplasty (TKA). Recent studies and meta-analysis indicate that dexmedetomidine combined with local anesthetics for FNB can prolong the analgesic duration, improve the analgesic efficacy, inhibit local inflammatory response, and reduce narcotic consumption. The investigators hypothesize that dexmedetomidine combined with ropivacaine for FNB can also improve functional recovery in aged patients after TKA.

Many patients following total knee arthroplasty (TKA) complain moderate to severe postoperative pain. Multimodal analgesia, a combination of different techniques and analgesic agents, plays an increasingly important role to relieve pain after TKA. Femoral nerve block (FNB) is a first-line analgesic technique for multimodal analgesia after TKA. But local anesthetics alone often exert limited potency of analgesia and are insufficient to avoid supplemental opioid usage. Dexmedetomidine, a selective alpha 2-adrenergic receptor agonist, is widely used in clinical settings due to its properties of sedation, anxiolysis, analgesia, and sleep promotion. Recent studies and meta-analysis indicate that dexmedetomidine combined with local anesthetics for FNB can prolong the analgesic duration, improve the analgesic efficacy, inhibit local inflammatory response, and reduce narcotic consumption. The investigators hypothesize that dexmedetomidine combined with ropivacaine for FNB can also improve the functional recovery in aged patients after TKA.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

QUADRUPLE

Enrollment

170

Conditions

Eligibility

Sex: ALLMin age: 65 YearsMax age: 89 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age ≥65 years but \<90 years; * Scheduled to undergo unilateral total knee arthroplasty; * Planned to use femoral nerve block and patient-controlled intravenous analgesia (PCIA) for multimodal analgesia. Exclusion Criteria: * Scheduled for bilateral total knee arthroplasty or revision surgery; * Contraindications to femoral nerve block; * Preoperative history of schizophrenia, myasthenia gravis, inability to communicate because of coma, severe dementia, or language barriers; * Preoperative history of hemorrhagic disease or coagulopathy; * Preoperative obstructive sleep apnea (diagnosed sleep apnea syndrome or a STOP-Bang score ≥3 combined with a serum bicarbonate ≥28 mmol/L); * Sick sinus syndrome, severe sinus bradycardia (\< 50 beats per minute), or second-degree or above atrioventricular block without pacemaker; * Severe hepatic dysfunction (Child-Pugh class C), severe renal dysfunction (requirement of renal replacement therapy before surgery), or American Society of Anesthesiologists physical status \>III; * Preexistent delirium (diagnosed by Three-Dimensional Confusion Assessment Method); * Under treatment with dexmedetomidine or clonidine.

Outcomes

Primary Outcomes

Quality of life at 3 months after surgery-mental component summary score

Quality of life is assessed with 12-item short-form (SF-12, it is summarized into physical and mental component summary scores, each ranges from 0 to 100, with higher scores indicating better quality of life).

Time frame: At 3 months after surgery

Secondary Outcomes

Incidence of delirium within the first 3 days after surgery

Delirium is assessed with the Three-dimensional Confusion Assessment Method (3D CAM) twice daily (8:00-10:00 and 18:00-20:00) over the first 3 postoperative hospital days. Patients with endotracheal intubation will be assessed with the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) twice daily during the same period.

Time frame: The first 3 days after surgery

Length of stay in hospital after surgery

Time frame: Up to 30 days after surgery

Incidence of non-delirium complications (including all-cause mortality) within 30 days after surgery

Time frame: Up to 30 days after surgery

Quality of life at 3 months after surgery-physical component summary score

Time frame: At 3 months after surgery

The overall subjective sleep quality at 3 months after surgery

Evaluated by the Pittsburgh Sleep Quality Index, which estimates overall subjective sleep quality in the past 30 days. Overall score ranges from 0 to 21. A higher score indicates worse sleep quality, and a score greater than 5 indicates poor sleep quality.

Time frame: At 3 months after surgery

The severity of arthritic symptoms at 3 months after surgery

Assessed with WOMAC osteoarthritis index (score ranges from 0 to 96, with higher score indicating more severe symptoms).

Time frame: At 3 months after surgery

Cognitive function at 3 months after surgery

Evaluated with the modified Telephone Interview for Cognitive Status (TICS-m), a 12-item questionnaire that provides an assessment of global cognitive function by verbal communication via telephone. The score ranges from 0 to 48, with higher score indicating better function.

Time frame: At 3 months after surgery

Event-free survival at 3 months after surgery

Time from surgery to new-onset diseases or all-cause death, whichever comes first. New-onset disease indicates those that required hospital admission and/or interventional procedure.

Time frame: At 3 months after surgery

Dexmedetomidine as an Adjuvant for Femoral Nerve Block and Functional Recovery After Total Knee Arthroplasty

Overview

Conditions

Interventions

Eligibility

Locations (2)

Outcomes

Primary Outcomes

Secondary Outcomes