Factors Associated With the Risk of Developing Moderate to Severe Acute Postoperative Pain After Primary Total Knee Arthroplasty: Results From the PAIN OUT Registry

Risk Factors for Acute Postsurgical Pain: A Narrative Review

Acute postsurgical pain (APSP) has received growing attention as a surgical outcome. When poorly controlled, APSP can affect short- and long-term outcomes in patients. Despite the steady increase in awareness about postoperative pain and standardization of pain prevention and treatment strategies, moderate-to-severe APSP is frequently reported in clinical practice. This is possibly because pain varies widely among individuals and is influenced by distinct factors, such as demographic, perioperative, psychological, and genetic factors. This review investigates the risk factors for APSP, including gender, age, obesity, smoking history, preoperative pain history, pain sensitivity, preoperative anxiety, depression, pain catastrophizing, expected postoperative pain, surgical fear, and genetic polymorphisms. By identifying patients having an increased risk of moderate-to-severe APSP at an early stage, clinicians can more effectively manage individualized analgesic treatment protocols with a combination of pharmacological and non-pharmacological interventions. This would alleviate the transition from APSP to chronic pain and reduce the severity of APSP-induced chronic physical disability and social psychological distress.

Sex moderates the association between quantitative sensory testing and acute and chronic pain after total knee/hip arthroplasty

OBJECTIVES

Acute postsurgical pain (APSP) may persist over time and become chronic. Research on predictors for APSP and chronic postsurgical pain (CPSP) has produced inconsistent results. This observational study aimed to analyze psychological and psychophysical variables associated with APSP and CPSP after total knee or hip arthroplasty, and to explore the role of sex.

METHODS

Assessments were conducted before surgery, 48 h, and 3 months postsurgery, including questionnaires (sociodemographic, pain related, and psychological) and quantitative sensory testing (QST). Hierarchical linear regression models analyzed potential predictors of APSP and CPSP, and moderation analyses evaluated the role of sex.

RESULTS

The study included 63 participants undergoing total knee (34, 54%) or hip (29, 46%) arthroplasty. Thirty-one (49.2%) were female and 32 (50.8%) were male. APSP (48 h) was associated with impaired conditioned pain modulation (CPM) (β = 0.301, p = 0.019). CPSP (3 months) was associated with being female (β = 0.282, p = 0.029), longer presurgical pain duration (β = 0.353, p = 0.006), knee arthroplasty (β = -0.312, p = 0.015), higher APSP intensity (β = 373, p = 0.004), and impaired CPM (β = 0.126, p = 0.004). In multivariate analysis, these clinical variables were significant predictors of CPSP, unlike sex, and CPM (adj. R 2 = 0.349). Moderation analyses showed that wind-up ratio (WUR) was a significant predictor of APSP in men (WUR × sex: b = -1.373, p = 0.046) and CPM was a significant predictor of CPSP in women (CPM × sex: b = 1.625, p = 0.016).

CONCLUSIONS

Specific QST parameters could identify patients at risk for high-intensity APSP and CPSP, with sex as a moderator. This has important clinical implications for patient care, paving the way for developing tailored preventive pain management strategies.

Chronic pain patients and time to sustained acceptable pain scores after major surgery - A retrospective registry analysis

STUDY OBJECTIVE

We tested the hypothesis that pre-existing chronic pain is associated with prolonged time to reach sustained acceptable pain scores after major surgery.

DESIGN

Retrospective study using the German Network for Safety in Regional Anaesthesia and Acute Pain Therapy registry.

SETTING

Operating rooms and surgical wards.

PATIENTS

107,412 patients recovering from major surgery who were cared for by an acute pain service. 3.3% of the treatments were in patients who reported chronic pain with functional or psychological impairment.

INTERVENTIONS AND MEASUREMENT

We compared time to sustained adequacy of postoperative pain control defined by numeric rating scores <4 at rest and with movement in patients with and without chronic pain using an adjusted cox proportional hazard regression model and Kaplan-Meier analysis. The observation period was censored at 10 days and propensity score matching was used as a sensitivity analysis.

MAIN RESULTS

Postoperative pain at rest took significantly longer to resolve in patients with chronic pain than in those without (adjusted hazard ratio HR 1.42, 95% CI 1.36-1.49, P < 0.001). Postoperative pain with movement took even longer to resolve in patients with chronic pain (adjusted HR 1.65, 95%CI 1.56-1.75, P < 0.001).

CONCLUSIONS

Patients with chronic pain sustain more surgical pain than those without, and the pain takes longer to resolve. Clinicians providing postoperative pain management should consider the special needs of chronic pain patients.

Trajectory of chronic and neuropathic pain, anxiety and depressive symptoms and pain catastrophizing after total knee replacement. Results of a prospective, single-center study at a mean follow-up of 7.5 years

INTRODUCTION

A considerable number of patients are not satisfied after total knee replacement (TKR) because of persistent pain. This pain can also be neuropathic in origin. Both types of pain have a large impact on function and quality of life. Furthermore, the trajectory of anxiety and depressive symptoms and pain catastrophizing has rarely been studied after TKR surgery. The primary objective of this study was to define the trajectory of knee pain after primary TKR. The secondary objectives were to evaluate how neuropathic pain, anxiety and depressive symptoms and pain catastrophizing change over time.

METHODS

This prospective, single-center study included patients who underwent primary TKR for primary osteoarthritis between July 2011 and December 2012. Personal data (age, sex, body mass index, knee history, operated side, surgical approach, type of implant, operative time, and rehabilitation course) and the responses to seven questionnaires (Numerical pain rating scale, DN4-interview for neuropathic pain, Oxford Knee Scale, Hospital and Anxiety Depression Scale, Beck Depression Inventory, Patient Catastrophizing Scale and Brief Pain Inventory) were determined preoperatively, at 6 months postoperative and at a mean follow-up of 7.5 years.

RESULTS

Preoperatively, 129 patients (35 men, 94 women) filled out all the questionnaires. Subsequently, 32 patients were excluded because of incomplete responses at 6 months postoperative, 6 were excluded because they had undergone revision surgery, 11 patients were lost to follow-up and 5 patients had died. In the end, 65 patients were available for analysis (50% of the initial cohort) who were 74 years old on average at inclusion. Between the preoperative period and 6 months postoperative, pain (p<0.001), function (p<0.001), anxiety symptoms (p<0.001) and catastrophizing (p<0.001) had improved. Depressive symptoms did not change (p=0.63). Between 6 months postoperative and the latest follow-up, none of the parameters changed further (p>0.05). Of the 65 patients analyzed, 21% had chronic pain of undefined origin at 6 months postoperative and 26% had chronic pain at the end of follow-up, with 50% also having neuropathic pain. Preoperatively, 40% of the 65 patients had neuropathic pain, 30% at 6 months (p=0.27) and 18% at 7.5 years after TKR (p=0.01).

CONCLUSION

The number of patients who have chronic pain after TKR is considerable, especially since knee pain stabilized at 6 months postoperative. Early detection is vital to prevent the pain from becoming chronic, which makes it more difficult to treat. Half the patients with persistent pain also had neuropathic pain, which should be detected before surgery so the patients can be referred to a specialized pain management center. The presence of anxiety and depressive symptoms and pain catastrophizing is not a contraindication to TKR, but these patients should be referred to specialists for treatment before surgery.

LEVEL OF EVIDENCE

IV, prospective cohort study.

High-dose dexamethasone in low pain responders undergoing total knee arthroplasty: a randomised double-blind trial

BACKGROUND

Postoperative pain after total knee arthroplasty (TKA) is a continuing problem despite optimised multimodal analgesia. Previous studies have shown preoperative glucocorticoids to reduce postoperative pain, but knowledge about specific doses and effects in specific patient groups is lacking.

METHODS

A two-centre, double-blind, two-arm study comparing preoperative dexamethasone (1 mg kg^-1vs 0.3 mg kg^-1 i.v.) on postoperative pain in 160 planned TKA subjects with low preoperative pain catastrophising and no opioid use. Subjects received multimodal analgesia with paracetamol, cyclooxygenase-2 inhibitors, local anaesthetic infiltration analgesia, and rescue opioids. The primary outcome was percentage of subjects experiencing moderate to severe pain (visual analogue scale >30 mm) upon ambulation at 24 h. Secondary outcomes included pain scores, postoperative inflammation (C-reactive protein), opioid and antiemetics use, and 'Quality of Recovery-15' and 'Opioid-Related Symptom Distress Scale', length of stay, readmissions, and complications up to Day 90.

RESULTS

A total of 157 subjects (80 vs 77) were included. No difference was found between groups in the incidence of subjects experiencing visual analogue scale >30 on ambulation 24 h after surgery (56% vs 53%, relative risk =1.07, confidence interval: 0.8-1.4, P=0.65). No differences in other pain outcomes or use of rescue opioids and antiemetics, in Quality of Recovery-15 and Opioid-Related Symptom Distress Scale, length of stay, readmissions, or complications. C-reactive protein values were comparable at 24 h (13 [6-25] mg L^-1vs 16 [9-38] mg L^-1, P = 0.07), but lower at 48 h (26 [9-52] mg L^-1vs 50 [30-72] mg L^-1, P<0.01) in the high-dose group.

CONCLUSION

Use of 1 mg kg^-1vs 0.3 mg kg^-1 i.v. dexamethasone in low pain responders after TKA did not improve early postoperative pain or other outcomes in contrast to benefits in a high pain responder population.

CLINICAL TRIAL REGISTRATION

NCT03758170 (first registration 29-11-2018).

Ultrasound-guided genicular nerves block vs. local infiltration analgesia for total knee arthroplasty: a randomised controlled non-inferiority trial

Genicular nerves block is a promising technique to treat acute postoperative pain in total knee arthroplasty. Similar to surgeon-administered local infiltration analgesia, it targets sensory branches from the knee capsule, but through a selective ultrasound-guided injection that reduces local anaesthetic dose (150 ml ropivacaine 0.2% with local infiltration analgesia vs. 20 ml with genicular nerves block). This randomised non-inferiority trial compared the analgesic efficacy of genicular nerves block vs. local infiltration analgesia in the first 24 h following total knee arthroplasty. Sixty patients were randomly allocated to receive either ultrasound-guided block of five genicular nerves or local infiltration analgesia. The primary outcome was rest pain numeric rating scale (0-10) at 24 h. Secondary outcomes included pain numeric rating scale (rest and movement) and cumulative opioid consumption during the first 24 h. We analysed 29 patients in the genicular nerves block group and 30 in the local infiltration analgesia group. We found that the median difference (95%CI) in postoperative rest pain at 24 h (non-inferiority criteria, Δ = 1) was -1.0 (-2.0 to 1.0, p < 0.001). Median difference in cumulative opioid consumption was 0.0 mg (-3.0-5.0, p < 0.001) meeting the non-inferiority criteria, Δ = 23 mg. We conclude that genicular nerves block of five nerves provides non-inferior analgesia in the first 24 h following surgery compared with local infiltration analgesia, but with a considerable reduction in the local anaesthetic dose.

Multimodal analgesia practices for knee and hip arthroplasties in the Netherlands. A prospective observational study from the PAIN OUT registry

INTRODUCTION

Different multimodal pain management strategies following total hip arthroplasty(THA) and total knee arthroplasty (TKA) surgery are used in clinical practice. The optimal pain management strategy, however, remains unclear. This study aims to evaluate the differences in perioperative multimodal pain management strategies for THA and TKA in the Netherlands, and studies the associations between patient- and therapy related factors and pain outcomes.

METHODS

Data from the Dutch hospitals in the PAIN OUT network were used in this study. Demographic data, pain management strategy including perioperative medication use and anesthetic techniques were recorded and used in a multivariable regression analysis to study the association with maximum pain intensity, the duration of severe pain, pain interference in bed and postoperative nausea.

RESULTS

In 343 hip arthroplasty patients and 301 knee arthroplasty patients in seven hospitals, respectively 28 and 35 different combinations of analgesic regimens were used. The number of different drugs prescribed was not related to postoperative pain intensity. Female sex, younger age and spinal anesthesia were associated with higher postoperative maximum pain scores (Numeric Rating Scale (NRS) > 5). Hip surgery and ketamine use were associated with lower postoperative pain scores. The use of non-steroidal anti-inflammatory drugs (NSAIDs) and gabapentinoids, higher age, higher body mass index (BMI) and male gender were associated with less postoperative nausea (NRS < 3).

CONCLUSION

In conclusion, our study demonstrated a large diversity of analgesic strategies following total joint arthroplasties in the Netherlands. Although no ideal strategy was identified, the use of NSAIDs, ketamine and dexamethasone were associated with less pain and less side effects.

Combined femoral and popliteal nerve block is superior to local periarticular infiltration anaesthesia for postoperative pain control after total knee arthroplasty

INTRODUCTION

After primary total knee arthroplasty (TKA), local periarticular infiltration anaesthesia (LIA) is a fast and safe method for postoperative pain control. Moreover, ultrasound-guided regional anaesthesia (USRA) with femoral and popliteal block is a standard procedure in perioperative care. Two analgesic regimens for TKA-LIA versus URSA with dexmedetomidine-were compared as an additive to ropivacaine. We hypothesised that the use of URSA provides a superior opioid sparing effect for TKA compared with LIA.

METHODS

Fifty patients (planned 188 participants; safety analysis was performed after examining the first 50 participants) were randomised. These patients received LIA into the knee capsule during surgery with 60 ml of ropivacaine 0.5% and 1 ml of dexmedetomidine (100 µg ml^-1) or two single-shot URSA blocks (femoral and popliteal block) before surgery with 15 ml of ropivacaine 0.5% and 0.5 ml of dexmedetomidine for each block. Postoperative opioid consumption in the first 48 h, pain assessment and complications were analysed.

RESULTS

In the safety analysis, there was a significantly higher need for opioids in the LIA group, with a median oral morphine equivalent of 42.0 [interquartile range (IQR) 23.5-57.0] mg versus 27.0 [IQR 0.0-33.5] mg (P = 0.022). Due to this finding, the study was terminated for ethical considerations according to the protocol.

CONCLUSION

This is the first study presenting data on LIA application in combination with dexmedetomidine. A superior opioid-sparing effect of URSA was observed when compared with LIA in TKA when dexmedetomidine is added to local anaesthetics. Also, a longer lasting opioid-sparing effect in the LIA group was observed when compared with the recently published literature; this difference could be attributed to the addition of dexmedetomidine. Therefore, multimodal analgesia regimens could be further improved when LIA or USRA techniques are combined with dexmedetomidine.