Postoperative cognitive dysfunction is rare after fast-track hip- and knee arthroplasty - But potentially related to opioid use.

STUDY OBJECTIVE: Postoperative cognitive dysfunction (POCD) remains a frequent postoperative complication in non-fast-track surgeries, with negative implications for return to daily activities and work. In fast-track total hip and -knee arthroplasty (THA/TKA) an 8-9% incidence of POCD after 3 months has been reported, but without details on specific perioperative risk factors. Thus, we re-investigated the incidence and role of suggested factors for POCD in a well-controlled patient cohort, to guide future preventive interventions. DESIGN: A subanalysis of a prospective study. SETTING: Hospital ward, patients own home. PATIENTS: One-hundred-and-four patients undergoing elective THA/TKA. INTERVENTIONS: A full contextual and validated cognitive test battery pre- and 2-3 weeks postoperatively by interview by research nurse. MEASUREMENTS: Results from the cognitive test battery were corrected for learning effect by normative data from an age-matched unoperated control group. Potential perioperative risk factors (age, procedure, gender, inflammation, blood-percentage, opioids etc.) associated with POCD was investigated by univariate and multivariate logistic analysis, with a 5% significance level. MAIN RESULTS: Four patients (3.9%) developed POCD. POCD-positive patients consumed higher dose of opioids in the acute postoperative period (postoperative days 0-3: median 214 mg), vs. POCD-negative patients (postoperative days 0-3: median 98 mg, p = 0.008), and during the 2-3-week study period (POCD-positive vs. POCD-negative patients, median 739 mg vs. 208 mg, respectively). Other pre and postoperative factors were non-significant but associated with the development of POCD. CONCLUSION: POCD is rare in fast-track THA/TKA patients and may be related to postoperative opioid consumption, supporting the ongoing focus on opioid-sparing analgesia.

Objectively measured early physical activity after total hip or knee arthroplasty.

Although reduced early physical function after total hip- and knee arthroplasty (THA/TKA) is well-described, the underlying reasons have not been clarified with detailed studies on pathophysiological mechanisms related to recovery, thereby prohibiting advances in rehabilitation. Thus, we aimed to describe early post-THA/TKA physical activity measured by actigraphy and potential underlying pathophysiological mechanisms related to recovery in a well-defined cohort of THA and TKA patients. Daytime-activity was measured from 2 days before until 13 (THA) or 20 (TKA) days after surgery. The primary outcome was individualized recovery in activity, with secondary analyses of activity-intensities and association to the perioperative factors: sex, age, BMI, hemoglobin (hgb), C-reactive protein and postoperative pain. Eighty-one THA/TKA-patients were examined. A large inter-individual variation in early physical activity was found. On a group level, activity was significantly reduced compared to preoperatively the first 2 (THA) or 3 (TKA) weeks after surgery (mean-difference - 64 counts × 103/day, p < 0.001 and - 78 counts × 103/day, p < 0.001, respectively). All activity-intensities were affected with the largest decline in high intense activity. A slight overall improvement in activity was seen during the postoperative phase [THA: 1%/day (SD 2.15); TKA: 0.7%/day (SD 1.04)], but approximately 30% of THA and 20% of TKA patients had reduced and declining activity. Hgb, CRP, BMI (THA) and postoperative pain (TKA) were only weakly associated with impaired physical activity. Physical activity was reduced the first weeks following THA/TKA, but with large inter-individual variations in recovery profiles. No single pathogenic factor was associated with a poor recovery. Early risk stratified interventions are needed in patients on a suboptimal course.

Prospective psychometric characterization of hip and knee arthroplasty patients.

BACKGROUND: Psychiatric conditions and psychopharmacological treatments have been demonstrated to be important risk-factors for prolonged hospital length of stay, readmission and morbidity, following fast-track total hip (THA) and total knee arthroplasty (TKA). AIMS: The aim of the study was to provide a detailed description of the preoperative psychiatric characteristics of a well-defined patient population undergoing THA and TKA, using the 90-item Symptom Checklist (SCL-90-R). METHODS: A pre-surgical population of 2183 patients completed the full SCL-90-R prior to THA/TKA from 2015 to 2016. The SCL-90-R scale and total scores of the pre-surgical sample were compared to the scores of an age- and gender stratified Danish sample of healthy controls. A Mokken scalogram analysis was conducted to assess the scalability of the SCL-90-R in both samples. RESULTS: The Mokken analysis yielded acceptable scalability coefficients above 0.30 in all subscales of the SCL-90-R except psycoticism (0.28). There was no clinically significant difference (effect size = <0.50) in the SCL-90-R total score between the pre-surgical and the healthy controls samples, although pre-surgical patients had lower mean scores compared to the healthy controls in all subscales except somatization (effect size = -0.22). CONCLUSION: The Mokken analysis demonstrated that the SCL-90-R and its subscales express valid measures of psychopathology in our surgical sample. The psychiatric profile of the pre-surgical patient sample indicates that patients undergoing THA/TKA are not more burdened by psychiatric symptoms than a healthy control group with the exception of symptoms relating to somatization.