Cerebral microembolization during primary total hip arthroplasty and neuropsychologic outcome: a pilot study

Risk of Perioperative Stroke in Patients with Patent Foramen Ovale: A Systematic Review and Meta-Analysis

BACKGROUND

Patent foramen ovale (PFO) is a common congenital cardiac abnormality. Risk of stroke increases perioperatively; however, the association of PFO with perioperative stroke risk remains unclear. We conducted a systematic review to inform the risk of perioperative stroke in patients with PFO undergoing surgery.

METHODS

EMBASE, MEDLINE, and Cochrane databases were searched from inception to January 2020. We described methods used for establishing PFO and perioperative stroke diagnosis. We conducted meta-analyses to obtain pooled estimates for risk of stroke in patients with and without PFO in different surgical populations.

RESULTS

Ten articles with a total of 20,858,011 patients met the eligibility criteria. Prevalence of PFO ranged from 0.06-1.4% based on ICD code diagnosis and 10.4-40.4% based on echocardiography diagnosis. Perioperative stroke was observed in 0-25% of patients with PFO, and 0-16.7% without PFO. Studies that use echocardiography to diagnose PFO found no association between PFO and perioperative stroke. Studies that used ICD codes, found strong association but were highly heterogenous. PFO was not associated with a risk of perioperative stroke in cardiac and transplant surgeries. While the adjusted odds ratios for stroke were substantial for orthopedic, general, genitourinary, neuro, and thoracic surgeries (with PFO status established based on ICD codes), data heterogeneity and quality of data create significant uncertainty.

CONCLUSION

In conclusion, PFO is likely a risk factor for perioperative stroke in select types of surgeries. However, this is based on a very low-quality evidence. Rigorous, prospective studies are needed to further investigate this relationship.

Postoperative Delirium and Postoperative Cognitive Dysfunction in Patients with Elective Hip or Knee Arthroplasty: A Narrative Review of the Literature

Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are common complications following total knee arthroplasty (TKA) and total hip arthroplasty (THA), affecting the length of hospital stay and increasing medical complications. Although many papers have been published on both conditions in this setting, no reviews have currently been written. Thus, the purpose of our study is to summarize the current literature and provide information about POD and POCD following elective THA or TKA. Our literature search was conducted in the electronic databases PubMed and the Cochrane library. We found that POD is a common complication following elective THA or TKA, with a median incidence of 14.8%. Major risk factors include older age, cognitive impairment, dementia, preoperative (pre-op) comorbidities, substance abuse, and surgery for fracture. Diagnosis can be achieved using tools such as the confusion assessment method (CAM), which is sensitive, specific, reliable, and easy to use, for the identification of POD. Treatment consists of risk stratification and the implementation of a multiple component prevention protocol. POCD has a median incidence of 19.3% at 1 week, and 10% at 3 months. Risk factors include older age, high BMI, and cognitive impairment. Treatment consists of reversing risk factors and implementing protocols in order to preserve physiological stability. POD and POCD are common and preventable complications following TKA and THA. Risk stratification and specific interventions can lower the incidence of both syndromes. Every physician involved in the care of such patients should be informed on every aspect of these conditions in order to provide the best care for their patients.

Preoperative Chronic Pain as a Risk Factor for Early Postoperative Cognitive Dysfunction in Elderly Patients Undergoing Hip Joint Replacement Surgery: A Prospective Observational Cohort Study

Background: Although major joint replacement surgery has a high overall success rate, postoperative cognitive dysfunction (POCD) is a common complication after anesthesia and surgery, increasing morbidity and mortality. Identifying POCD risk factors would be helpful to prevent and decrease the occurrence of POCD. We hypothesized that preoperative chronic pain increases the risk of POCD.

Methods: A single-center, observational, prospective cohort study was conducted from January 2018 to March 2020. All consecutive elderly patients (>65 years) who underwent elective total hip arthroplasty or hemiarthroplasty with general anesthesia by the same surgeon were enrolled. The patients underwent neuropsychological testing preoperatively and at 7 days and 2 months after surgery. To determine POCD, a nonsurgical control group was recruited from the general community.

Results: Of the 141 patients who finished the neuropsychological testing 7 days after surgery, 61 (43.2%) had preoperative chronic pain. Of the 61 patients, 17 (27.9%) developed POCD; of the 79 patients with no chronic pain, 10 (12.7%) had developed POCD by 7 days after surgery. Multivariate logistic regression analysis identified preoperative chronic pain as a risk factor of POCD assessed 7 days after surgery (odds ratio 6.527; P = 0.009). There was no significant difference in the POCD incidence 2 months after surgery between patients with and without preoperative chronic pain.

Conclusion: Preoperative chronic pain was a risk factor of developing POCD within 7 days after surgery in elderly patients following hip joint replacement surgery.

Clinical Trial Registration: [www.ClinicalTrials.gov], identifier [NCT03393676].

Tourniquet use in total knee replacement surgery: a feasibility study and pilot randomised controlled trial (SAFE-TKR study)

INTRODUCTION

Tourniquets are routinely used during total knee replacement (TKR) surgery. They could increase the risk of thromboembolic events including cerebral emboli, cognitive decline, pain and other adverse events (AEs). A randomised controlled trial to assess whether tourniquet use might safely be avoided is therefore warranted but it is unclear whether such a trial would be feasible.

METHODS

In a single-site feasibility study and pilot randomised controlled trial, adults having a TKR were randomised to surgery with an inflated tourniquet versus a non-inflated tourniquet. Participants underwent brain MRI preoperatively and within 2 days postoperatively. We assessed cognition using the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and Oxford Cognitive Screen (OCS) and thigh pain using a Visual Analogue Scale at baseline and days 1 and 2, and 1 week postsurgery. AEs related to surgery were recorded up to 12 months.

RESULTS

We randomised 53 participants (27 tourniquet inflated and 26 tourniquet not inflated). Fifty-one participants received care per-protocol (96%) and 48 (91%) were followed up at 12 months. One new ischaemic brain lesion was detected. Of the cognitive tests, MoCA was easy to summarise, sensitive to change with lower ceiling effects compared with OCS and MMSE. There was a trend towards more thigh pain (mean 49.6 SD 30.4 vs 36.2 SD 28 at day 1) and more AEs related to surgery (21 vs 9) in participants with an inflated tourniquet compared with those with a tourniquet not inflated.

CONCLUSION

A full trial is feasible, but using MRI as a primary outcome is unlikely to be appropriate or feasible. Suitable primary outcomes would be cognition measured using MoCA, pain and AEs, all of which warrant investigation in a large multicentre trial.

TRIAL REGISTRATION NUMBER

ISRCTN20873088.

Review article: Patient characteristics that act as risk factors for intraoperative complications in hip, knee, and shoulder arthroplasties

The number of annual THA's, TKA's, and TSA's is set to increase significantly by the year 2030, making it imperative to understand the risks for negative outcomes in these procedures. While research has studied the patient risk factors for perioperative and postoperative complications, there has been relatively little research for intraoperative complications. After a thorough literature review, the most supported finding was that patients with a BMI >30 had significantly more intraoperative blood loss than those with a BMI <30. All other relationships between patient risk factors and intraoperative complications of interest were inadequately studied.

The use of point-of-care ultrasound to diagnose patent foramen ovale in elective hip and knee arthroplasty patients and its association with postoperative delirium

PURPOSE

Hip and knee arthroplasty surgeries are associated with embolism of materials such as air, cement, and fat. Patent foramen ovale (PFO) is a common congenital cardiac condition that has been reported to lead to paradoxical embolism. This observational study aimed to investigate if the presence of a PFO was associated with an increased risk of postoperative delirium in patients undergoing primary elective hip or knee arthroplasties.

METHOD

This was a prospective cohort study at a tertiary teaching hospital. We enrolled patients undergoing primary elective hip or knee arthroplasty who did not have any risk factors for embolism or delirium. Bedside transthoracic echocardiography (TTE) with a bubble study was performed on all patients to detect the presence of PFO. The primary outcome was postoperative delirium as assessed by the standardized Confusion Assessment Method. Secondary outcomes included the ease of performing a TTE bubble study in the perioperative setting, the quality of the TTE images, length of stay, major cardiovascular and neurologic complications, and effects of anesthetic or analgesic management techniques on delirium.

RESULTS

Two hundred two patients completed the study. The median [interquartile range] duration of stay was 2 [2-3] days. Only 16 patients (8%) had a positive bubble study. Postoperative delirium was observed in only one patient. Major adverse events were not seen. The inter-rater reliability for the TTE image quality scores was fair (kappa statistic = 0.22).

CONCLUSION

Given the very low incidence of PFO and postoperative delirium in this study, we could not form any conclusions regarding the impact of a PFO on important outcomes including delirium or other major adverse events. No recommendation can be made regarding screening for PFO in patients scheduled for lower extremity arthroplasty surgery.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT02400892). Registered 27 March 2015.

Atrial Septal Defect Increases the Risk for Stroke After Total Hip Arthroplasty

BACKGROUND

Atrial septal defect (ASD) and patent foramen ovale (PFO) are 2 of the most common congenital heart diseases in adults and pose important risks of perioperative acute ischemic stroke (AIS) from paradoxical emboli. We evaluated the following: (1) the prevalence of ASD/PFO in the total hip arthroplasty (THA) population; (2) the rate of perioperative AIS during index admissions; and (3) the risk for perioperative AIS after THA for patients with ASD/PFO vs matched controls.

METHODS

We identified 393,652 patients in the Nationwide Inpatient Sample who underwent THA between January 1, 2007, and December 31, 2013. The International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes were used to identify patients with ASD/PFO and perioperative AIS. Propensity scores matched 252 patients with ASD/PFO to 756 controls (3:1 ratio) without ASD/PFO according to age, gender, race, Deyo comorbidity score, year of surgery, and stroke risk factors. Logistic regression models assessed risk for perioperative AIS.

RESULTS

The prevalence of ASD/PFO was 64 per 100,000 THA patients. The rate of perioperative AIS was 99 per 100,000 THA in the general THA population. The rate of perioperative AIS was 7.14% for ASD/PFO patients compared with 0.26% in matched controls (P < .001). Risk for perioperative AIS was 29 times greater for patients with ASD/PFO compared with matched controls (odds ratio, 29.00; 95% confidence interval, 6.68-125.89; P < .001).

CONCLUSION

Patients with ASD/PFO undergoing THA are at a significantly higher risk of perioperative AIS. Orthopedic surgeons should discuss this risk with patients before surgery. The efficacy of mechanical and pharmacologic thromboprophylactic measures to reduce perioperative AIS among ASD/PFO patients warrants further investigation.

Depression and anxiety after total joint replacement among older adults: a meta-analysis

OBJECTIVE

Patients usually experience good physical recovery after total joint replacement (TJR); however, it is unclear whether mood also improves. The current meta-analysis examined changes in depression and anxiety following TJR in older (≥50 years) patients in order to address this gap in the literature.

METHODS

Data from 26 studies (4045 TJR, 55 controls) that assessed depression and/or anxiety pre- and post-surgery in TJR patients, with or without a control group, were analyzed. Prevalence rates and Cohen's d effect sizes were used to evaluate changes in the prevalence and severity of depression/anxiety, respectively.

RESULTS

Approximately 23% of TJR patients had clinically significant levels of depression prior to surgery, which decreased to 13% one year later. The prevalence of anxiety could not be evaluated due to the limited available data. TJR patients did not show any clinically meaningful reductions in symptoms of depression or anxiety, following surgery. Compared to controls, there was no difference in symptom progression over time; although only one study examined this.

CONCLUSIONS

TJR patients appear to have higher rates of clinically significant symptoms of depression before and after surgery, compared to the general population, however more research with adequate control groups is needed to confirm this. Only a modest improvement in the severity of depression and anxiety symptoms was noted post-surgery. However, existing research is limited; preventing definite conclusions regarding the impact of TJR on mood.

Postoperative cognitive dysfunction after total joint arthroplasty in the elderly: a meta-analysis

This meta-analysis consolidated the research on postoperative cognitive dysfunction (POCD) following total joint arthroplasty (TJA). Data from 17 studies that assessed cognition pre- and post-surgery in TJA patients alone (15 studies) or matched TJA and control groups (2 studies) were analysed. Results were grouped by cognitive domain (memory, attention, language, speed, general cognition) and follow-up interval (pre-discharge, 3-6 months post-surgery). The TJA data revealed small declines in reaction time and general cognition pre-discharge, but no evidence of decline 3-6 months post-surgery. Very limited TJA and Control data indicated no group differences in the changes to performance over time; however, the TJA group was cognitively compromised pre- and post-surgery compared to Controls. Further appropriately controlled research is required to clarify whether POCD commonly occurs after TJA.

Review of transcranial Doppler ultrasound to detect microemboli during orthopedic surgery

Transcranial Doppler ultrasonography has been used to detect microemboli in the middle cerebral artery during orthopedic surgery. We conducted a comprehensive systematic literature review of transcranial Doppler ultrasonography in orthopedic surgery to evaluate its status in this setting. Fourteen studies were selected for qualitative analysis. The highest number of patients studied was 45; emboli were detected in all studies, occurring in 20%-100% of patients. Most embolic counts were below 10, but some high counts were noted. No study reported all the technical parameters of the transcranial Doppler ultrasonography. All studies assessed neurologic status, and 6 studies evaluated cognitive function postoperatively. No study identified an association between postoperative cognitive function and embolic count. Six studies sought the presence of right-to-left shunts.