Associations between seasonal variation and post-operative complications after total hip arthroplasty

Worsening of anemia increases the risks of complications and prolonged length of stay following revision total shoulder arthroplasty

Background

There are no studies currently in the literature that assesses complications following revision total shoulder arthroplasty (TSA) in patients with varying severity of anemia. The purpose of this study was to determine the impact of preoperative anemia severity on postoperative complications following revision TSA.

Methods

Patients undergoing revision TSA from 2013 to 2019 were queried in a national database. Based on previous studies' definitions of anemia, three subgroups were stratified: patients without anemia (hematocrit >36% for women, hematocrit >39% for men), patients with mild anemia (hematocrit 33% to 36% for women, hematocrit 33% to 39% for men) and patients with moderate to severe anemia (hematocrit <33% for both women and men). In this analysis, patient demographics, comorbidities, and postoperative complications were compared between the three groups.

Results

Of 1559 total patients undergoing revision TSA, 1178 patients (75.6%) did not have anemia, 255 (16.3%) had mild anemia, and 126 (8.1%) had moderate/severe anemia. Following adjustment on multivariate analysis, patients with mild anemia were more likely to have postoperative transfusion and extended length of stay compared to non-anemic patients. Patients with moderate/severe anemia were at increased risk of postoperative transfusion, sepsis, extended length of stay, and reoperation compared to non-anemic patients.

Discussion

From mild anemia to moderate/severe anemia, there was a stepwise increase in the risk of postoperative complications. Our study showed that there is clinical value in the preoperative correction of anemia for these patients as it relates to complications and hospital stay.

Level of Evidence

III.

The Association of Season of Surgery and Patient Reported Outcomes following Total Hip Arthroplasty

Background

Understanding the impact of situational variables on surgical recovery can improve outcomes in total hip arthroplasty (THA). Literature examining hospital outcomes by season remains inconclusive, with limited focus on patient experience. The aim of this study is to investigate if there are differences in hospital and patient-reported outcomes measures (PROMS) after THA depending on the season of the index procedure to improve surgeon preoperative counseling.

Methods

A retrospective chart review was performed on patients undergoing primary THA at a single large academic center between January 2013 and August 2020. Demographic, operative, hospital, and PROMs were gathered from the institutional electronic medical record and our institutional joint replacement outcomes database.

Results

6418 patients underwent primary THA and met inclusion criteria. Of this patient population, 1636 underwent surgery in winter, 1543 in spring, 1811 in summer, and 1428 in fall. PROMs were equivalent across seasons at nearly time points. The average age of patients was 65 (+/- 10) years, with an average BMI of 29.3 (+/- 6). Rates of complications including ED visits within 30 days, readmission within 90 days, unplanned readmission, dislocation, fracture, or wound infection were not significantly different by season (P > .05).

Conclusion

Our findings indicate no differences in complications and PROMs at 1 year in patients undergoing THA during 4 distinct seasons. Notably, patients had functional differences at the second follow-up visit, suggesting variation in short-term recovery. Patients could be counseled that they have similar rates of complications and postoperative recovery regardless of season.

Influenza Season and Outcome After Elective Cardiac Surgery: An Observational Cohort Study

BACKGROUND

An asymptomatic respiratory viral infection during cardiac surgery could lead to pulmonary complications and increased mortality. For elective surgery, testing for respiratory viral infection before surgery or vaccination could reduce the number of these pulmonary complications. The aim of this study was to investigate the association between influenzalike illness (ILI) seasons and prolonged mechanical ventilation and inhospital mortality in a Dutch cohort of adult elective cardiac surgery patients.

METHODS

Cardiac surgery patients who were admitted to the intensive care unit between January 1, 2014, and February 1, 2020, were included. The primary endpoint was the duration of invasive mechanical ventilation in the ILI season compared with baseline season. Secondary endpoints were the median Pao2 to fraction of inspired oxygen ratio on days 1, 3, and 7 and postoperative inhospital mortality.

RESULTS

A total of 42,277 patients underwent cardiac surgery, 12,994 (30.7%) in the ILI season, 15,843 (37.5%) in the intermediate season, and 13,440 (31.8%) in the baseline season. No hazard rates indicative of a longer duration of invasive mechanical ventilation during the ILI season were found. No differences were found for the median Pao2 to fraction of inspired oxygen ratio between seasons. However, inhospital mortality was higher in the ILI season compared with baseline season (odds ratio 1.67; 95% CI, 1.14-2.46).

CONCLUSIONS

Patients undergoing cardiac surgery during the ILI season were at increased risk of inhospital mortality compared with patients in the baseline season. No evidence was found that this difference is caused by direct postoperative pulmonary complications.

Understanding the 30-day mortality burden after revision total hip arthroplasty

BACKGROUND

Revision total hip arthroplasty (THA) is a challenging procedure that burdens the healthcare system. Despite being associated with worse outcomes relative to its primary counterpart, postoperative mortality after revision THA remains ill-defined. The present study aimed to (1) establish the overall 30-day mortality rate after revision THA and (2) explore the mortality rate stratified by age, comorbidity burden, and aseptic versus septic failure.

METHODS

The American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) database was retrospectively reviewed for all patients who underwent revision THA from 2011 to 2019. A total of 23,501 patients were identified and grouped into mortality (n = 161) and mortality-free (n = 23,340) cohorts. Patient demographics, comorbidities, and aseptic/septic failure were evaluated.

RESULTS

The overall 30-day mortality was 0.69%. The mortality rate by age group (normalised per 1000 patients) was 0 (18-39 years [Y]), 0.67 (40-49 Y), 1.10 (50-59 Y), 2.58 (60-69 Y), 6.15 (70-79 Y) 19.32 (80-89 Y), and 58.22 (90+Y) (p < 0.001). The mortality rate by ASA classification (normalised per 1000 patients) was 0 (ASA I), 1.47 (ASA II), 6.94 (ASA III), 45.42 (ASA IV), and 200 (ASA V) (p < 0.001). The 30-day mortality rate for the septic and aseptic cohorts was 1.03% and 0.65%, respectively (p = 0.038). CCI scores (p < 0.001), diabetes (p < 0.001), systematic sepsis (p < 0.001), poor functional status (p < 0.001), BMI < 24.9 kg/m2 (p < 0.001), and dirty/infected wounds (p < 0.001) were all associated with increased mortality risk.

CONCLUSIONS

1 in 145 patients will suffer mortality during the 30 days after revision THA. PJI-related revision THA was associated with 1.5-fold increase in 30-day mortality rate compared to its aseptic counterpart. Certain patient determinants and baseline comorbidities, as measured by ASA and CCI scores, were associated with higher 30-day mortality rates. Therefore, it is imperative to identify such risk factors and implement perioperative patient optimisation pathways to mitigate the risk among vulnerable patients.

How to Create an Orthopaedic Arthroplasty Administrative Database Project: A Step-by-Step Guide Part I: Study Design

BACKGROUND

Use of clinical and administrative databases in orthopaedic surgery research has grown substantially in recent years. It is estimated that approximately 10% of all published lower extremity arthroplasty research have been database studies. The aim of this review is to serve as a guide on how to (1) design, (2) execute, and (3) publish an orthopaedic administrative database arthroplasty project.

METHODS

In part I, we discuss how to develop a research question and choose a database (when databases should/should not be used), detailing advantages/disadvantages of those most commonly used. To date, the most commonly published databases in orthopaedic research have been the National Inpatient Sample, Medicare, National Surgical Quality Improvement Program, and those provided by PearlDiver. General advantages of most database studies include accessibility, affordability compared to prospective research studies, ease of use, large sample sizes, and the ability to identify trends and aggregate outcomes of multiple health care systems/providers.

RESULTS

Disadvantages of most databases include their retrospective observational nature, limitations of procedural/billing coding, relatively short follow-up, limited ability to control for confounding variables, and lack of functional/patient-reported outcomes.

CONCLUSION

Although this study is not all-encompassing, we hope it will serve as a starting point for those interested in conducting and critically reviewing lower extremity arthroplasty database studies.

The Impact of Month on Joint Arthroplasty In-Hospital Outcomes: The December Effect

Background

The purpose of this study was to assess the impact of month of the year on postsurgical outcomes after primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) and to specifically analyze for a December effect.

Material and methods

The National Inpatient Sample was used to identify all patients older than 40 years undergoing primary TKA and THA between 2006 and 2015. Patients were stratified based on the month of the year of surgery. In-hospital complication, disposition, and economic outcomes were comparatively analyzed.

Results

There were statistically significant differences in outcomes based on month of the year. When comparing December to the other months, both TKA and THA patients had significantly lower rates of any complication, postoperative anemia, and genitourinary complications, while there were significantly higher rates of home than rehab discharge and shorter average length of stay in December. THA patients additionally had significantly lower rates of cardiac and respiratory complications during December.

Conclusion

Postoperative outcomes are significantly associated with the month in which arthroplasty is performed. This study provides evidence of a positive "December effect" of improved in-hospital complications and economic outcomes for surgeries performed in December. Future research should direct attention to the impact that social factors may have on outcomes after elective surgical procedures and how these factors may be translated to other months.

Understanding the 30-day mortality burden after revision total knee arthroplasty

Background

In revision total knee arthroplasty (TKA), information regarding perioperative mortality risk is essential for careful decision-making. This study aimed to elucidate the (1) overall 30-day mortality rate and (2) 30-day mortality rate stratified by age, comorbidity, and septic vs aseptic failure after revision TKA.

Methods

The American College of Surgeons National Surgical Quality Improvement Program was reviewed for all patients undergoing revision TKA from 2011 to 2019. A total of 32,354 patients who underwent TKA were identified and categorized as mortality (n = 115) or mortality-free (n = 32,239). Patient characteristics were compared between cohorts and further stratified by septic and aseptic failure.

Results

The overall 30-day mortality rate was 0.36%. The percentage of deaths per age group (normalized per 1000) was 0% (18-29 years), 0% (30-39 years), 0.18% (40-49 years), 0.13% (50-59 years), 0.14% (60-69 years), 0.40% (70-79 years), 1.25% (80-89 years), and 6.93% (90+ years). The percentage of deaths per American Society of Anesthesiologists (ASA) class was 0.30% (ASA 1), 0.06% (ASA 2), 0.39% (ASA 3), 2.41% (ASA 4), and 14.29% (ASA 5). Septic revision (P < .001), general anesthesia (P < .001), body mass index ≤ 24.9 (P < .001), and insulin-dependent diabetes (P = .039) were associated with an increased risk of mortality.

Conclusions

Increasing age, greater comorbidity burden, underweight or normal body mass index, insulin-dependent diabetes, septic revision, and general anesthesia were all associated with an increased risk of mortality after revision TKA. Notably, 1 in 80 patients aged 80-89 years died after revision TKA compared to 1 in 720 patients aged 60-69 years. Patients who underwent septic revision had a 4-fold increase in mortality compared to aseptic revision. Our stratified assessment of mortality provides a more individualized estimation of risk that can be used for patient counseling in revision TKA.

What Is the 30-Day Mortality Burden After Elective Total Hip Arthroplasty? An Analysis of 194,062 Patients

BACKGROUND

This study aims to answer the following questions regarding elective total hip arthroplasty (THA): What is (1) the overall 30-day mortality rate; (2) the mortality rate when stratified by age, comorbidities, and preoperative diagnosis; and (3) the distribution of patient demographics, comorbidities, and preoperative diagnoses between the mortality and mortality-free cohorts?

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was reviewed for all patients undergoing elective primary THA (2011-2018). A total of 194,062 patients were categorized based on the incidence of 30-day mortality (mortality: n = 206 vs mortality-free: n = 193,856). Patient demographics, comorbidities, and preoperative diagnosis (osteoarthritis [OA] vs non-OA) were recorded. Age category, American Society of Anesthesiologists (ASA) score, and modified Charlson Comorbidity Index (CCI) scores were normalized per 1000 and stratified by preoperative diagnosis.

RESULTS

The 30-day mortality rate was 0.11%. The percentage of deaths per age group (normalized per 1000) was 0% (18-29 years), 0% (30-39 years), 0.049% (40-49 years), 0.052%(50-59 years), 0.071% (60-69 years), 0.133% (70-79 years), and 0.352% (80-89 years). The percentage of deaths per ASA score was 0% (ASA I), 0.035% (ASA II), 0.174% (ASA III), and 1.008% (ASA IV). The percentage of deaths per CCI score was 0.09% (CCI = 0), 0.23% (CCI = 1), 0.74% (CCI = 2), 3.21% (CCI = 3), 4.76% (CCI = 4), and 0.57% (CCI ≥ 5). Non-OA diagnoses were significantly more frequent in the mortality cohort (16.0% vs 7.6%; P < .001).

CONCLUSION

The risk of mortality was highest in patients aged 80-89, patients of ASA class IV, patients with a CCI score of 4, and patients with a non-OA diagnosis. The overall rate of death was higher in the non-OA cohort compared to the OA cohort.

LEVEL OF EVIDENCE

III.

Warm Weather and Surgical Site Infections: A Meta-analysis

Seasonal variability, in terms of warm weather, has been demonstrated to be a significant risk factor for surgical site infections (SSIs). However, this remains an underexposed risk factor for SSIs, and many clinicians are not aware of this. Therefore, a systematic review and meta-analysis has been conducted to investigate and quantify this matter.

METHODS

Articles were searched in Embase, Medline Ovid, Web of Science, Cochrane Central, and Google Scholar, and data were extracted from relevant studies. Meta-analysis used random effects models to estimate and compare the pooled odds ratios (OR) and corresponding confidence intervals (CIs) of surgery performed during the warmest period of the year and the colder period of the year.

RESULTS

The systematic review included 20 studies (58,599,475 patients), of which 14 studies (58,441,420 patients) were included for meta-analysis. Various types of surgical procedures across different geographic regions were included. The warmest period of the year was associated with a statistically significant increase in the risk of SSIs (OR 1.39, 95%CI: [1.34-1.45], P < 0.0001). Selection of specific types of surgical procedures (eg, orthopedic or spinal surgery) significantly altered this increased risk.

CONCLUSIONS

The current meta-analysis showed that warm weather seasons are associated with a statistically significant risk increasement of 39% in developing SSIs. This significant risk factor might aid clinicians in preoperative patient information, possible surgical planning adjustment for high risk patients, and potentially specific antibiotic treatments during the warmer weather seasons that could result in decrease of SSIs.

Hypovitaminosis D in lower extremity Joint Arthroplasty: A systematic review and meta-analysis

The purpose of the current systematic review was to identify the prevalence of hypovitaminosis-D in LE-TJA patients; and outline the association between pre-operative hypovitaminosis and post-operative outcomes. A search of PubMed-Medline and the Cochrane-Library databases was performed for literature published before November 27th, 2019. The eighteen studies analyzed had a pooled prevalence for vitamin D insufficiency (20 - <30 ng/mL) and deficiency (<20 ng/mL) of 53.4% and 39.4%, respectively. Hypovitaminosis-D was associated with higher complication rates (p = 0.043), and a greater prevalence among septic versus aseptic revisions (p = 0.016). Therefore, pre-operative screening for hypovitaminosis-D can be beneficial in patients undergoing LE-TJA.

LEVEL OF EVIDENCE

Systematic Review (Level III).

Do new trainees pose a threat to postoperative complications after hip fracture surgeries? Retrospective cohort of 1045 patients over a decade at a university hospital

Introduction

Induction of new residents and surgical trainees in most institutes occurs once a year. Fresh residents with no experience, may pose a threat to the surgical procedure outcome and there can be a potential increase in patients' morbidity and mortality as a result of this turnover. Literature is inconclusive about this effect. Our aim was to study the "new residents' induction effect" on postoperative complications after hip fracture surgeries.

Methodology

This is non funded non commercialized study from a university hospital. Investigators studied a retrospective cohort of 1045 adult hip fracture patients who were operated at our tertiary care and level 1 trauma centre of a metropolitan city between 2008 and 2018. We defined primary exposure as the time period of new resident's induction (January-March) with the primary outcome in-hospital and 30days postoperative complications. Cox proportional hazard algorithm analysis was done at univariate and multivariable levels reporting Crude Relative Risk (RR) and Adjusted Relative Risk (aRR), respectively. Results were reported in line with STROBE criteria.

Results

There were 274 (26%) patients in exposed group out of whom 109 (40%) developed postoperative complications. Interestingly, patients who had their surgeries during the induction period of new residents had 8% less risk of developing postoperative complications. However, result was statistically insignificant at both univariate and multivariable levels with RR; 95% C.I of 0.9 (0.78-1.22) and aRR; 95% C.I of 0.9 (0.78-1.22) after adjusting for the all other independent variables.

Conclusion

The association of new residents' induction on postoperative hip fracture surgery complications, although protective, was insignificant after controlling for the potential confounding effect of patients' background and demographic characteristics. We recommend further multi-centre high powered studies to analyze this.

Seasonal influence on postoperative hip fracture complications: Retrospective cohort of more than 1000 patients from a tertiary-care university hospital

Background

Hip fractures account for one of the most debilitating conditions affecting the general population amongst the developed and developing nations. Investigators aimed to study the influence of the ongoing season i.e. whether patients operated upon in summer or winter, on post-operative complications occurring within 30 days of surgical procedure for hip fractures at a tertiary care hospital and level 1 trauma center.

Materials and methods

Investigators conducted a non-funded, non-commercialized retrospective cohort of 1045 patients with hip fractures managed surgically. Primary exposure was surgical procedures undertaken during the summer months (April–September). Our primary outcome was determining post-operative complication rates from January 2010 to December 2018 and evaluating impact of the season through univariate and multivariable regression analyses using Cox Proportional Hazard Algorithm with STATA V15. The work has been reported in line with the STROCSS criteria.

Results

Age, ASA status, type of procedure, mechanism of injury and Charlson Comorbidity Index (CCI) were identified as significant associated factors with postoperative complications after hip fracture surgery. Although overall results revealed a rising rate of complications during the summer season with a relative risk (RR; 95% CI) of 1.1(0.89–1.32), univariate and multivariable analysis did not show any significant correlations.

Conclusions

The results of this study did not demonstrate a significant seasonal variability in the rate of postoperative complications for hip fracture patients operated upon during the hot months of summer. More research is required to analyze postoperative complications in order to optimize patients’ outcomes.

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The number of hip fractures has been observed to double as the population ages.

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Surgical management is the gold standard and most effective management option.

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Operating patients during summer is postulated to carry higher risk of postoperative complications.

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However, this higher risk was statistically insignificant in the current study.

Seasonal effect on the incidence of post-operative wound complications after trauma-related surgery of the foot, ankle and lower leg

INTRODUCTION

Post-operative wound complications remain among the most common complications of orthopedic (trauma) surgery. Recently, studies have suggested environmental factors such as season to be of influence on wound complications. Patients operated in summer are reported to have more wound complications, compared to other seasons. The aim of this study was to identify if "seasonality" was a significant predictor for wound complications in this cohort of trauma-related foot/ankle procedures.

MATERIALS AND METHODS

This retrospective cohort study included all patients undergoing trauma-related surgery (e.g. fracture fixation, arthrodesis, implant removal) of the foot, ankle or lower leg. Procedures were performed at a Level 1 Trauma Center between September 2015 until March 2019. Potential risk factors/confounders were identified using univariate analysis. Procedures were divided into two groups: (1) performed in summer (June, July or August), (2) other seasons (September-May). The number of surgical wound complications (FRIs, SSIs or wound dehiscence) was compared between the two groups, corrected for confounders, using multivariate regression.

RESULTS

A total of 599 procedures were included, mostly performed in the hindfoot (47.6%). Patients were on average 46 years old, and mostly male (60.8%). The total number of wound complications was 43 (7.2%). Age, alcohol abuse, open fracture and no tourniquet use were independent predicting factors. No difference in wound complications was found between summer and other seasons, neither in univariate analysis [4 (3.2%) vs 39 (8.2%), p = 0.086] nor when corrected for predicting factors as confounders (p = 0.096).

CONCLUSIONS

No seasonality could be identified in the rate of wound complications after trauma surgery of the lower leg, ankle and foot in this cohort. This lack of effect might result from the temperate climate of this cohort. Larger temperature and precipitation differences may influence wound complications to a larger extent. However, previous studies suggesting seasonality in wound complications might also be based on coincidence.

High prevalence and seasonal variation of hypovitaminosis D in patients scheduled for lower extremity total joint arthroplasty

Background

High rates of vitamin D insufficiency and deficiency have been demonstrated in various patient populations, including patients undergoing total joint arthroplasties (TJA). However, the risk factors associated with this condition and its seasonal variation is still to be determined in patients scheduled for elective TJA.

Methods

We retrospectively identified 226 (116 hips, 120 knees) patients who underwent primary TJA, and had a vitamin D measurement, at a single institution (latitude, 41° 30' N) from 2006 to 2016. Demographics, comorbidities, and perioperative data were collected from electronic medical records. Patients were stratified into vitamin D sufficient (≥30 ng/mL), insufficient (<30 ng/mL), and deficient group (<20 ng/mL). Multivariate regression analyses were used to study the risk factors for vitamin D insufficiency and deficiency.

Results

There were 99/226 (43.8%) patients in the vitamin D sufficient group, 137/226 patients (60.6%) in the insufficient group, of which 61/226 (26.9%) were in the deficient group. On multivariate analysis, an American Society of Anesthesiologists' (ASA) score ≥3 was a risk factor for vitamin D insufficiency (P<0.001), while ASA ≥3 (P<0.001) and younger age (P=0.002) were risk factors for vitamin D deficiency. Vitamin D levels varied between the quarters with lowest level seen in quarter 1 (P=0.015).

Conclusions

There was an overall high prevalence of vitamin D insufficiency (60%) and deficiency (27%). Due to higher risk of hypovitaminosis D, particular attention should be placed in patients with an ASA score ≥3, and patients scheduled during winter season.