The increased utilization of operating room time in patients with increased BMI during primary total hip arthroplasty

The Effect of Obesity on Hemiarthroplasty and Total Hip Arthroplasty for Femoral Neck Fractures

Obesity is a well-recognized global epidemic that can lead to longer operative times as well as a greater technical demand. Despite this, the available literature evaluating the impact of obesity on hip hemiarthroplasty (HA) and total hip arthroplasty (THA) when treating fractures about the femoral neck is scarce. Between 2015 and 2018, we retrospectively reviewed all patients that had a HA or THA performed as treatment for an isolated fracture of the femoral neck. Patients were classified as obese and nonobese depending on current body mass index (BMI) when the index procedure was performed. Preoperative and postoperative variable were obtained from the electronic medical record. A total of 157 patients underwent hip HA or THA for an isolated fracture of the femoral neck. In those patients undergoing HA, obesity was associated with an increase in operative times (P = 0.021) and was associated with a nonsignificant increase in total operating room time (P = 0.088) and duration of anesthesia (P = 0.14). In those patients undergoing THA, obesity was associated with longer operative times (P = 0.043), total operating room time (P = 0.032), and duration of anesthesia (P = 0.045). There were no significant differences in complication rates postoperatively between obese and non-obese patients undergoing either procedure. The treatment of isolated fractures of the femoral neck with HA or THA leads to an increase in operative time without an increase in postoperative complications in obese patients.

Hip arthroscopy versus total hip arthroplasty-A study on patients with obesity above 40 years of age

Patients older than 40 years with a body-mass-index (BMI) >30 kg/m2 , a femoroacetabular-impingement (FAI) and little cartilage damage are a challenge for hip surgeons. Hip-arthroscopy (HAS) or conservative therapy until a total hip arthroplasty (THA) is needed are possible treatments. Our research purpose was to compare the clinical results and complication/reoperation rate after HAS and THA in patients with obesity over 40 years. This retrospective study includes a consecutive series of patients with obesity (BMI >30 kg/m2 ) who underwent HAS (19 hips) and THA (37 hips) over 40 years of age between 2007 and 2013 at our institution with a minimum of 12-months follow-up. Outcome measures were WOMAC (Western Ontario und McMaster Universities Arthritis Index), subjective-hip-value (SHV), residual complaints and the reoperation rate. Patient data and scores were collected pre-operative, 12 months post-operatively and at the last follow-up. Both groups showed a comparable age (mean 48 years). Regarding SHV-Scores the THA-group shows continuous significant improvements. Reaching 87% (range 50%-100%), the HAS-group showed in case of the SHV no significant change after 1 year and an improvement from preoperative to the last follow-up reaching 72% (range 30%-100%) at the last follow-up. Residual groin pain was significant higher in the HAS-group. Two deep infections (5.4%) requiring reoperations were reported in the THA-group. The conversion rate to THA after a mean time of 60 months was 26% (5 of 19). Patients with obesity over 40 years demonstrated inferior SHV, more often residual pain and revision surgery after HAS, when compared to THA at short-term, with conversions rate of one fourth. However, THA in this patient group showed high infection rate of 5%. This information is relevant for counselling above-mentioned patients.

Do TKAs in Patients with Higher BMI Take Longer, and is the Difference Associated with Surgeon Volume? A Large-database Study from a National Arthroplasty Registry

BACKGROUND

Increased surgical time in TKA may impact economic costs and clinical outcomes. Prior work has found that TKAs in patients with high BMI take longer, and these patients may be at greater risk for postoperative complications like infection. However, these studies included small numbers of patients and surgeons from single institutions and they did not consider surgeon volume.

QUESTIONS/PURPOSES

Using the New Zealand Joint Registry (NZJR), we asked: (1) Is there a relationship between increasing patient BMI and TKA operative time? (2) Is the effect of BMI on surgical time less pronounced among surgeons who perform more TKAs per year than those who perform fewer?

METHODS

Data were collected from the NZJR between January 2010 and December 2018 as it is the only national registry that records both BMI and surgical time. Primary TKA performed for osteoarthritis by surgeons with more than 50 TKAs over the period of the study were identified. BMI and operative time (skin incision to closure in minutes) were recorded. Patients with the following were excluded: lateral parapatellar or minimally invasive approaches; navigated, patient-specific instrumentation, or robot-assisted TKA; uncemented or hybrid fixation; those with procedures performed by a trainee (all or part); or a nonosteoarthritic indication. Of 64,108 TKAs performed during the study period, a total of 42% (27,057) met our inclusion criteria. The primary outcome was the effect of BMI on operative time. Operative time is expressed in minutes as a mean for each single-unit BMI increase across all surgeons, controlled for other variables that might influence operative time such as patella resurfacing and cruciate-retaining versus posterior-stabilized designs. Overall, the mean operative time (skin incision to closure) was 79 ± 22 minutes. Surgical experience was assessed by subdividing surgeons into six groups according to the number of TKAs performed annually (< 10, 10 to 24, 25 to 49, 50 to 74, 75 to 99, and > 100). Statistical analyses were performed including a general linear model to assess the independent association between BMI and operative time, allowing for the effects of other patient and surgical features. In addition, linear regression analyses explored the associations between BMI and operative time in the whole group and within surgical volume groups.

RESULTS

There was an association between increasing BMI and increasing surgical duration. The mean operative time increased from 75 ± 22 minutes in patients with a normal BMI of 25 kg/m2 to 87 ± 24 minutes in patients with a BMI of 40 kg/m2 to 94 ± 28 minutes in patients with a BMI > 50 kg/m2 (p < 0.001). Surgeons performing fewer than 25 TKAs per year took 14% longer to perform a TKA on a patient with a BMI of 40 kg/m2 than on a patient with a normal BMI of 25 kg/m2. However, surgeons performing greater than 25 TKAs per year took 10% longer.

CONCLUSION

In this study, an increase BMI was associated with increased surgical time in TKA. Surgical duration for high-volume surgeons appears less influenced by increases in BMI than lower volume surgeons. Although the absolute increase in duration was small, prolonged surgical time may reduce theater productivity. Even though the issues around managing patients with high BMI are multifactorial and complex, considerations from these findings include ensuring appropriate theater scheduling and possibly referring patients with high BMI to specialist centers. Further studies should focus on assessing the effectiveness of such measures in reducing complications and improving outcomes in patients with elevated BMI.

LEVEL OF EVIDENCE

Level III, therapeutic study.

The Association of Body Mass Index with Surgical Time Is Mediated by Comorbidity in Patients Undergoing Total Hip Arthroplasty

Overweight represents a major issue in contemporary orthopaedic practice. A higher body mass index (BMI) is associated with an increase of perioperative complications following several orthopaedic procedures, in particular total hip arthroplasty (THA). However, the influence of overweight on THA surgical time is controversial. In this study, we investigated the association between BMI and surgical time analyzing the role of patients’ comorbidities. We conducted a retrospective study on 748 patients undergoing THA at our institutions between 2017 and 2018. Information regarding medical diseases was investigated and the burden of comorbidity was quantified using the Charlson score (CCI). Surgical time and blood loss were also recorded. Median surgical time was 76.5 min. Patients with surgical time above the median had both a higher BMI (28.3 vs. 27.1 kg/m²; p = 0.002); and CCI (1 vs. 0; p = 0.016). According to linear regression, surgical time was associated with BMI in the unadjusted model (p < 0.0001), after adjusting for age and sex (p < 0.0001), and in the multivariable model (p = 0.005). Furthermore, BMI was associated with increased surgical time only in patients with a Charlson score above the median, but not in others. Obesity is associated with increased surgical time during THA, especially in pluricomorbid patients, with a higher risk of perioperative complications.

Elective Surgery in Adult Patients with Excess Weight: Can Preoperative Dietary Interventions Improve Surgical Outcomes? A Systematic Review

This systematic review summarises the literature regarding the impact of preoperative dietary interventions on non-bariatric surgery outcomes for patients with excess weight/obesity, a known risk factor for poor surgical outcomes. Four electronic databases were searched for non-bariatric surgery studies that evaluated the surgical outcomes of a preoperative diet that focused on weight/fat loss or improvement of liver steatosis. Meta-analysis was unfeasible due to the extreme heterogeneity of variables. Fourteen studies, including five randomised controlled trials, were selected. Laparoscopic cholecystectomy, hernia repair, and liver resection were most studied. Diet-induced weight loss ranged from 1.4 kg to 25 kg. Preoperative very low calorie diet (≤800 kcal) or low calorie diet (≤900 kcal) for one to three weeks resulted in: reduction in blood loss for two liver resection and one gastrectomy study (-27 to -411 mL, p < 0.05), and for laparoscopic cholecystectomy, reduction of six minutes in operating time (p < 0.05) and reduced difficulty of aspects of procedure (p < 0.05). There was no difference in length of stay (n = 7 studies). Preoperative ≤ 900 kcal diets for one to three weeks could improve surgical outcomes for laparoscopic cholecystectomy, liver resection, and gastrectomy. Multiple randomised controlled trials with common surgical outcomes are required to establish impact on other surgeries.

The Effect of Obesity on Operating Room Utilization in Breast Surgery

BACKGROUND

The current obesity epidemic is associated with increased health care costs associated with comorbidities such as diabetes and heart disease as well as postoperative complications. However, the effect of obesity on operating room (OR) utilization, especially in common breast procedures, has not been completely evaluated. Our study is the first to examine the effect of patient obesity on operative time (OPT) for common breast procedures.

METHODS

The American College of Surgeons National Surgical Quality Improvement Project databases for 2010-2018 were searched for this retrospective review. Patients undergoing common breast operations (lumpectomy, lumpectomy with sentinel lymph node biopsy (SLNB) (+/- injection), lumpectomy and axillary lymph node dissection (ALND), simple mastectomy, mastectomy with SLNB (+/- injection), and mastectomy with ALND) were filtered out by Current Procedural Terminology code and divided into three groups based on their body mass index (BMI) and weight. Using the two-sample t-test, OPT for the procedures was compared among the lowest and highest BMI and weight categories. We also used a linear regression t-test to demonstrate that for every unit increase in BMI, there was a corresponding increase in OPT for each procedure.

RESULTS

When the lowest and highest BMI and weight groups were compared, significant differences in OPT (P < 0.0001) were seen for each of the procedures. Numerous factors that could affect the complexity of surgery and thus OR time were identified. The correlation between BMI and weight and OPT remained significant after controlling for these variables. The differences between the highest and lowest BMI groups were most pronounced for higher complexity procedures, such as lumpectomy with ALND and mastectomy with ALND, with average operating times increasing by 18.2 min and 18.6 min, respectively, for patients with a higher BMI.

CONCLUSIONS

Patient BMI and weight significantly affect OPT for common breast procedures. Therefore, patient BMI should be taken into account to improve OR scheduling.

Nutritional Counseling Program for Morbidly Obese Patients Enables Weight Optimization for Safe Total Joint Arthroplasty

Obesity affects one-third of total joint arthroplasty (TJA) patients and is the most common modifiable risk factor for increased complications in the TJA population. The authors' institution implemented a body mass index (BMI) cutoff of 40 kg/m² to define appropriate TJA candidates. Patients above the cutoff were referred for nutritional counseling. The study objective was to evaluate the efficacy of this protocol in optimizing patient BMI for safe and successful TJA. Between 2016 and 2018, the authors examined 133 patients (mean age, 62.6 years) with a BMI greater than 40 kg/m² seeking TJA (94 knee, 39 hip) seen by an arthroplasty surgeon and then a dietitian. Outcomes included weight loss, change in BMI, duration of counseling, and surgical status. For postoperative patients, 90-day complications were recorded. A total of 102 (92%) patients achieved weight loss during a mean 154 days (range, 8-601 days). Patients lost a mean of 17 lb, lowering their BMI by 2.7 points (range, +6.3 to -17.7 points). Twenty-two patients discontinued nutritional counseling after 1 visit, most commonly secondary to cost when not covered by insurance. Seventy-one patients successfully underwent TJA, representing 64% of those patients who participated in nutritional counseling. Complications included delayed wound healing (n=2), periprosthetic fracture (n=2), infection (n=1), cellulitis (n=1), and peroneal nerve palsy (n=1). Surgeons must actively counsel obese patients about weight optimization as part of the preoperative standard of care. Nutritional counseling with a dietitian and follow-up with the surgeon translated to safe and successful TJA in a majority of patients. [Orthopedics. 2020;43(4):e316-e322.].

Predictive value of lateral soft tissue thickness for complications after total hip arthroplasty with a lateral incision

The purpose of this study was to determine the relationship between soft tissue thickness lateral to the greater trochanter, as measured on anteroposterior pelvis radiograph, and postoperative complications following primary total hip arthroplasty. A retrospective review of 1110 consecutive patients treated at a single institution from 2003 to 2011 was conducted. Postoperative complications were divided into surgical site infections, deep wound infections, noninfectious surgical complications, need for revision surgery, and medical complications. Lateral soft tissue thickness (LSTT) was measured as the horizontal distance from the most lateral point on the greater trochanter to the skin edge obtained from anteroposterior hip radiographs. Among the 1110 study patients, 19.19% had a postoperative complication, with a deep infection rate of 3.42%. Of the previously identified risk factors, increased LSTT and body mass index were both associated with surgical site infection and deep infection, and LSTT was associated with revision surgery. An LSTT value of >5 cm was predictive of surgical site infection, deep infection, and revision surgery. This easily obtainable radiographic measurement, along with clinical examination near the operative site, might prove helpful in making preoperative risk assessments.

Operative Times Have Remained Stable for Total Hip Arthroplasty for >15 Years: Systematic Review of 630,675 Procedures

Understanding trends in operative times has become increasingly important in light of total hip arthroplasty (THA) being added to the Centers for Medicare & Medicaid Services (CMS) 2019 Potentially Misvalued Codes List. The purpose of this review was to explore the mean THA operative times reported in the literature in order (1) to determine if they have increased, decreased, or remained the same for patients reported on between 2000 and 2019 and (2) to determine what factors might have contributed to the difference (or lack thereof) in THA operative time over a contemporary study period.

METHODS

The PubMed and EBSCOhost databases were queried to identify all articles, published between 2000 and 2019, that reported on THA operative times. The keywords used were "operative," "time," and "total hip arthroplasty." An article was included if the full text was available, it was written in English, and it reported operative times of THAs. An article was excluded if it did not discuss operative time; it reported only comparative, rather than absolute, operative times; or the cohort consisted of total knee arthroplasties (TKAs) and THAs, exclusively of revision THAs, or exclusively of robotic THAs. Data on manual or primary THAs were extracted from studies including robotic or revision THAs. Thirty-five articles reporting on 630,675 hips that underwent THA between 1996 and 2016 met our criteria.

RESULTS

The overall weighted average operative time was 93.20 minutes (range, 55.65 to 149.00 minutes). When the study cohorts were stratified according to average operative time, the highest number fell into the 90 to 99-minute range. Operative time was stable throughout the years reported. Factors that led to increased operative times included increased body mass index (BMI), less surgical experience, and the presence of a trainee.

CONCLUSIONS

The average operative time across the included articles was approximately 95 minutes and has been relatively stable over the past 2 decades. On the basis of our findings, we cannot support CMS lowering the procedural valuation of THA given the stability of its operative times and the relationship between operative time and cost.

Relationship between Body Mass Index and Complications during the First 45 Days after Primary Total Hip and Knee Replacement: A Single-Center Study from South America

Background

The goal of this study was to evaluate the relationship between body mass index (BMI) and early complications of total hip replacement (THR) and total knee replacement (TKR).

Methods

This is a retrospective study of patients who underwent primary THR and TKR between January 2011 and December 2015. We included patients between 18 and 90 years of age with BMI less than 40 kg/m² with a minimal postoperative follow-up time of 45 days. The primary outcomes were the presence of infection, mechanical complications (dislocation, fractures, arthrofibrosis, or neuropraxia), and thromboembolic events. Overweight and obesity were defined as a BMI of 25-29.9 kg/m² and ≥ 30 kg/m², respectively.

Results

In total 750 patients were included (THR, 268; TKR, 482) with a mean age of 65.0 ± 12.4 years. The percentage of patients with normal weight, overweight, and obesity was 24.9% (n = 187), 41.7% (n = 313), and 33.4% (n = 250), respectively. The early complication rate was 8.9% (95% confidence interval [CI], 7.1% to 11.2%). Infection and mechanical complications were most prevalent. There was no statistically significant relationship between the incidence of complications and BMI (obesity vs. normal weight: hazard ratio [HR], 1.49; 95% CI, 0.72 to 3.06; p = 0.282); however, there was a tendency toward a greater risk of infectious complications in the patients with obesity (HR, 6.08; 95% CI, 0.75 to 49.16; p = 0.090). Patients with diabetes mellitus (DM) had more risk of infectious complications than those without DM (HR, 2.60; 95% CI, 1.00 to 6.79).

Conclusions

There was no statistical relationship between BMI and early complications of THR and TKR. Nonetheless, there was a tendency toward a higher risk of infection in patients with some degree of obesity.

Factors Affecting Operative Duration in Isolated Open Carpal Tunnel Release

Background  Open carpal tunnel release (CTR) is one of the most commonly performed operative procedures with operative duration being a primary metric of operating room efficiency. The purpose of this study was to identify factors associated with prolonged operative duration, in performing CTR. Materials and Methods  CTR cases performed by a single surgeon from September 2013 to October 2015 were reviewed. Patient age at the time of surgery, sex, location of surgery (specialty orthopaedic hospital versus ambulatory surgery center), body mass index (BMI), American Society of Anesthesiologists classification, total operative duration (TOD), and procedure time (PT) were recorded. Obesity was defined as BMI > 30 and morbid obesity was defined as BMI > 35. Data were analyzed to identify factors associated with prolonged TOD or PT. Results  One hundred and nine consecutive patients underwent isolated CTR. Mean age at time of surgery was 62 years (range: 24-92 years). Nonobese patients were found to have significantly shorter TOD than obese patients (22.3 vs. 24.4 minutes). Similarly, patients who were not morbidly obese had significantly shorter TOD than morbidly obese patients (22.6 vs. 26 minutes). No other factors were associated with prolonged TOD. No difference in PT was found between normal weight, obese, and morbidly obese groups. Conclusions  TOD, but not procedure time, is significantly affected by obesity. Our findings are relevant when scheduling and preparing obese patients for surgery, which may have a significant impact on health resource utilization. Level of Evidence  This is a Level III, economic/decision analysis study.

Risk factors for prolonged operative time in femoral neck fracture patients undergoing hemiarthroplasty through direct anterior approach

BACKGROUND

The use of direct anterior approach (DAA) for hemiarthroplasty in femoral neck fracture patients has recently increased worldwide. However, no previous studies have elucidated or validated risk factors for prolonged operative time in hemiarthroplasty through DAA. Accurately predicting operative time would contribute to and the selection of the most appropriate surgical approach for each patient and the effective use of operating room.

METHODS

Data from 151 femoral neck fracture patients who underwent hemiarthroplasty through DAA were evaluated. A multiple linear regression model of the operative time of hemiarthroplasty was developed, including age, sex, body mass index (BMI), surgeons' DAA experience and approach depth (cm) on the axial computed tomography (CT) slice of the hip as independent factors.

RESULTS

Mean age at admission was 83.8 [±6.3 standard deviation (SD)] years and mean operative time was 93.1 (±21 SD) min. Operative time increased by 20 min for every 1 cm increase in approach depth [partial regression coefficient (B), 20.4; standardized partial regression coefficient (β), 0.68; p < 0.001] and increased 13 min when the DAA was performed by a surgeon with DAA experience of <20 cases (B, 13.1; β, 0.29; p < 0.001). The adjusted R² of the model was 0.57.

CONCLUSIONS

We demonstrated that increased approach depth and surgeons' DAA experience (<20 cases) are novel risk factors for prolonged operative time in femoral neck fracture patients undergoing hemiarthroplasty through DAA. Surgeons should consider these factors when estimating the operative time of surgery and selecting the most appropriate and safe surgical approach for a patient undergoing hemiarthroplasty.

Impact of Body Mass Index on Perioperative Outcomes of Endoscopic Pituitary Surgery

Background Endoscopic pituitary surgery (EPS) is increasingly being used for the treatment of pituitary lesions. Obesity is a growing epidemic in our nation associated with numerous comorbidities known to impact surgical outcomes. We present a multi-institutional database study evaluating the association between body mass index (BMI) and postsurgical outcomes of EPS. Methods Patients who underwent EPS from 2005 to 2013 were identified from the American College of Surgeons National Surgical Quality Improvement Program database. Preoperative variables, comorbidities, and postoperative outcomes, such as 30-day complications, morbidity, and mortality, were analyzed. Results A total of 789 patients were analyzed, of which 382 were obese (BMI ≥ 30) (48.4%). No difference in reoperation rate ( P = .928) or unplanned readmission rates ( P = .837) was found between the obese versus nonobese group. A higher overall complication rate was observed in the obese group compared to the nonobese counterparts ( P = .005). However, when separated into surgical complications (3.7% vs 1.5%, P = .068) and medical complications (7.6% vs 3.9%, P = .027), only medical complications, specifically pneumonia, remained significantly different. EPS on obese patients was also associated with prolonged operating time (154.8 min vs 141.0 min, P = .011). Conclusions EPS may be a safe treatment option for pituitary lesions in the obese population. Although obese patients undergoing EPS are at increased risk of medical complications and prolonged operating times, this did not influence mortality, reoperation, or readmission rate.

The influence of obesity on operating room time and perioperative complications in cochlear implantation

Objective

The rising incidence of obesity in the United States is associated with increased healthcare expenditures and resource allocation. Obesity has been associated with prolonged operating times during surgical procedures. The primary objective of this study is to compare body mass index (BMI) to length of surgery during cochlear implantation.

Methods

A retrospective case control study from a tertiary academic referral center was performed. Patients included were adults who underwent primary, single-sided cochlear implantation with documented BMI and operating room (OR) times from January 2009 to July 2015. The following data were collected: BMI, total operating room time (TORT), surgical operating room time (SORT), ASA status, perioperative and postoperative complications, age, and gender.

Results

Two hundreds and thirty-four patients were included and stratified into obese (BMI >30) and non-obese (BMI < 30) categories. Statistical analysis was performed comparing TORT against the obesity category along with other variables. Independent sample t-test demonstrated that obesity increases TORT and SORT by 16.8 min (P = 0.0002) and 9.3 min (P = 0.03), respectively, compared to the non-obese group. Multivariate linear regression analysis demonstrated no statistically significant impact of gender, or ASA status on total operating or surgical time. Obesity was associated with increased perioperative complications (odds ratio [OR], 6.21; 95% CI, 1.18–32.80; P = 0.03) and postoperative complications (OR, 3.97; 95% CI, 1.29–12.26; P = 0.02).

Conclusions

Obesity leads to longer TORT and SORT during primary cochlear implant surgery. Obesity is also associated with increased perioperative and postoperative complications compared to non-obese patients. These data have implications with utilization of operating room resources.

Morbid Obesity in Total Knee Arthroplasty: Joint-Specific Variance in Outcomes for Operative Time, Length of Stay, and Readmission

BACKGROUND

It is increasingly apparent that the effect of obesity in arthroplasty is joint-specific. This study evaluates the effects of morbid obesity on primary total knee arthroplasty by comparing short-term outcomes between a morbidly obese (body mass index ≥40 kg/m²) and a normal weight (body mass index 18.5-<25 kg/m²) cohort at our institution between January 2003 and December 2010.

METHODS

One hundred seventeen morbidly obese patients were compared with 94 normal weight patients. Operative time, length of stay, complications, 30-day readmission, and readmission length were compared.

RESULTS

Morbid obesity conveyed no significant increase in 30-day readmission. Operative time was increased at 100 minutes in the morbidly obese group, compared with 90.5 minutes (P = .026).

CONCLUSION

Morbid obesity conveyed no increased risk of length of stay or readmission in this cohort.

The influence of patient- and surgeon-specific factors on operative duration and early postoperative outcomes in shoulder arthroplasty

BACKGROUND

Increased operative duration has been shown to have demonstrable effects on the outcomes and complications in multiple areas of orthopedic surgery. We sought to determine if patient- and surgeon-specific factors correlated to operative duration in shoulder arthroplasty. Our hypothesis was that increased surgeon and trainee volume would decrease operative times and that more complex pathology would increase operative duration.

METHODS

A retrospective review of primary and revision total and reverse shoulder arthroplasties performed at a single institution from 2012 through 2015 was performed evaluating the correlation between specific patient and surgeon factors and operative duration. The influence of operative duration on postoperative length of stay and risk of readmission within 30 days was also analyzed.

RESULTS

For surgeon-specific factors, high surgeon volume (>30 shoulder arthroplasties/year) was associated with shorter operative duration (105.9 vs. 128.3 minutes; P < .001). Progression through the fellowship academic year was found to be associated with decreased surgical times (100.7 vs. 116.5 minutes; P < .0001). Certain complex pathologic processes (reverse shoulder arthroplasty for sequelae of prior fracture, total shoulder arthroplasty for dysplastic glenoid morphology, revision surgery) showed increased operative times. Patients with postoperative readmission had a longer mean operative time (163 vs. 107.1 minutes).

CONCLUSIONS

Increased surgeon and trainee volumes were associated with decreased operative duration in shoulder arthroplasty. Patients with more complex pathology were more likely to have increased surgical times. Postoperative readmission within 30 days was associated with increased operative duration. Consideration of patient selection by surgeons to minimize operative times may reduce readmissions.

Use of Historical Surgical Times to Predict Duration of Primary Total Knee Arthroplasty

BACKGROUND

Primary total knee arthroplasty (TKA) is one of the most commonly performed procedures at US hospitals. Surgeons are typically asked to estimate surgical control time (SCT) needed for the procedure. Here, we compare the performance of a surgeon's prediction against a potentially more accurate method of using historical averages over the last 3, 5, 10, and 20 cases.

METHODS

Data were collected on all scheduled primary TKAs done at one institution from October 2008 to September 2014. For each case, actual SCT (aSCT) and predicted SCT were obtained. Historical SCTs were calculated based on the mean of the last 3, 5, 10, and 20 aSCTs of the same surgeon. Estimation biases were calculated based on the difference between aSCT and predicted SCT or between aSCT and historical estimates. Values were compared using Kruskal-Wallis analysis of variance and Steel-Dwass pairwise comparisons.

RESULTS

A total of 2539 primary TKAs were evaluated across 9 surgeons. Surgeons overestimated SCT by an average of 18.1 minutes. Using 3-20 cases in the historical average reduced mean estimation bias to a range of -0.1 to -0.3 minutes (P < .001). None of the historical estimations were significantly different from each other, demonstrating a lack of improvement with additional cases (P < .001).

CONCLUSION

Historical averages of procedure times appear to be a promising method of estimating surgical time for primary TKAs. Here, we show that even a small number of cases (eg, 3) can reduce estimation biases compared to solely using surgeons' estimates alone.

Preoperative Optimization of Total Joint Arthroplasty Surgical Risk: Obesity

Obesity is a problem that is increasing in prevalence in the United States and in other countries, and it is a common comorbidity in patients seeking total joint arthroplasty for degenerative musculoskeletal diseases. Obesity, as well as commonly associated comorbidities such as diabetes mellitus, cardiovascular disease, and those contributing to the diagnosis of metabolic syndrome, have been shown to have detrimental effects on total joint arthroplasty outcomes. Although there are effective surgical and nonsurgical interventions which can result in weight loss in these patients, concomitant benefit on arthroplasty outcomes is not clear. Preoperative optimization of surgical risk in obese total joint arthroplasty patients is an important point of intervention to improve arthroplasty outcomes.

Hip Arthroplasty in Obese Patients: Rising Prevalence-Standard Procedures?

We examined our experience and, in particular, complications associated with total hip arthroplasty in obese and morbidly obese patients. We prospectively gathered 50 patients in a matched control series including 25 obese and morbidly obese patients. All patients were operated using the direct lateral approach and standard postoperative protocols. Operating room time, complications, dislocations, blood loss, cup position and clinical parameters using the Harris Hip Score and the Western Ontario and McMaster Universities Arthritis Index results were compared. Although there were some significant differences in clinical outcomes, standard procedures yielded good overall results and an acceptable rate of complications. Details approaching this patient entity are being discussed.

Distribution of Subcutaneous Fat Around the Hip in Relation to Surgical Approach for Total Hip Arthroplasty

BACKGROUND

Although preoperative risk assessment is multifactorial, subcutaneous fat thickness at the incision site has been associated with postoperative complications in studies of total hip arthroplasty (THA) and other procedures. This study compared subcutaneous fat thickness encountered in THA approaches using a lateral hip incision with that of approaches using an anterior incision and examined the relationship between body mass index (BMI) and fat distribution based on sex and age.

METHODS

Subcutaneous fat measurements were obtained from 2004 patient CT images at positions that correspond with lateral and anterior incision sites for common approaches to THA. A thickness ratio (lateral/anterior) was calculated, and BMI, sex, and age were collected via chart review.

RESULTS

Males and females had significantly different thickness ratio averages at 1.97 and 2.68, respectively. Thickness ratios were not significantly different between BMI groups. Lateral thickness averages were significantly different for males and females, and the interaction between sex and BMI group was significant. The relationship between BMI and the thickness ratio in males aged ≥65 years was significantly different from males of <65 years and females of all ages.

CONCLUSION

Regardless of BMI, sex, or age, incision site soft tissue thickness was greater for approaches using a lateral hip incision than for those with an anterior incision, and a positive relationship between BMI and both measurements was identified. The predominance of lateral fat was more pronounced in females of all age and BMI groups and less pronounced in obese males aged ≥65 years.

Hip and knee arthroplasty implants contraindicated in obesity

INTRODUCTION

High patient weight is a risk factor for mechanical implant failure and some manufacturers list obesity as a contraindication for implant use. We reviewed data from the 2012-2013 UK National Joint Registry to determine whether surgical practice reflects these manufacturer recommendations.

METHODS

The product literature for the most commonly used hip and knee implants was reviewed for recommendations against use in obese patients (body mass index [BMI] ≥ 30kg/m(2)). The total number of obese patients undergoing hip and knee arthroplasty was calculated, as was the proportion receiving implants against manufacturer recommendations.

RESULTS

Out of 200,054 patient records, 147,691 (74%) had a recorded BMI. The mean BMI for patients undergoing primary total hip arthroplasty was 29kg/m(2), compared with 31kg/m(2) for total knee arthroplasty. Of the 25 components reviewed, 5 listed obesity as a contraindication or recommended against implant use in obese patients. A total of 10,745 patients (16% of all obese patients) received implants against manufacturer recommendations.

CONCLUSIONS

A high proportion of patients are receiving implants against manufacturer recommendations. However, there are limitations to using BMI for stratifying risk of implant fatigue failure and manufacturers should therefore provide more detailed guidelines on size specific implant load limits to facilitate surgical decisions.

Morbid Obesity and Congestive Heart Failure Increase Operative Time and Room Time in Total Hip Arthroplasty

BACKGROUND

Obesity is increasingly common in patients having total hip arthroplasty, and previous studies have shown a correlation with increased operative time in total hip arthroplasty. Decreasing operative time and room time is essential to meeting the increased demand for total hip arthroplasty, and factors that influence these metrics should be quantified to allow for targeted reduction in time and adjusted reimbursement models. This is the first study to use a multivariate approach to identify which factors increase operative time and room time in total hip arthroplasty.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was used to identify a cohort of 30,361 patients having total hip arthroplasty between 2006 and 2012. Patient demographics, comorbidities including body mass index, and anesthesia type were used to create generalized linear models identifying independent predictors of increased operative time and room time.

RESULTS

Morbid obesity (body mass index >40) independently increased operative time by 13 minutes and room time 18 by minutes. Congestive heart failure led to the greatest increase in overall room time, resulting in a 20-minute increase. Anesthesia method further influenced room time, with general anesthesia resulting in an increased room time of 18 minutes compared with spinal or regional anesthesia.

CONCLUSION

Obesity is the major driver of increased operative time in total hip arthroplasty. Congestive heart failure, general anesthesia, and morbid obesity each lead to substantial increases in overall room time, with congestive heart failure leading to the greatest increase in overall room time.

Urinary Retention is Rare After Total Joint Arthroplasty When Using Opioid-Free Regional Anesthesia

BACKGROUND

Postoperative urinary retention (POUR) is a relatively common complication after total joint arthroplasty (TJA). Based on the findings of a randomized, prospective study from our institution, we abandoned the routine use of indwelling urinary catheters in patients undergoing elective TJA using opioid-free spinal anesthesia. The aim of this study was to determine the incidence of and the risk factors for POUR in this patient population.

PATIENTS AND METHODS

A total of 842 consecutive patients underwent TJA between January 2012 and September 2014 using opioid-free spinal anesthesia in whom indwelling urinary catheters were not used. Postoperative urinary retention was defined as the inability of a patient to void that necessitated the placement of either an indwelling urinary catheter or straight catheterization. Multivariate logistic regression analysis was used to determine risk factors for developing POUR.

RESULTS

In this cohort, 79 patients (79/842; 9.3%) developed POUR. Independent risk factors for POUR were history of a benign prostatic hyperplasia (P = .02), renal disease (P = .001), longer operative time (P = .003), and age older than 67 years (P = .02). No patients in this cohort developed neurogenic bladder.

CONCLUSION

This study confirms that the routine use of indwelling urinary catheters for patients undergoing TJA using an opioid-free spinal anesthesia may not be warranted. Urinary catheters may be used selectively in patients at risk for subsequent urinary retention.

The Influence of Body Mass Index and Hip Anatomy on Direct Anterior Approach Total Hip Replacement

OBJECTIVE

To investigate the influence of body mass index (BMI) and hip anatomy on direct anterior approach (DAA) total hip replacement.

SUBJECTS AND METHODS

The study is a retrospective analysis of 124 cases of DAA total hip replacement from 2009 to 2012. The BMI, the ratio of the greater trochanter (GT) and anterior superior iliac spine (ASIS) bilaterally (GT/ASIS), and the vertical distance between the ASIS and GT (AGVD) were obtained from medical records. All cases were categorized into three groups (43, 49, and 32 cases in each group, respectively) based on BMI (BMI <18.5, BMI 18.5-25, and BMI >25) or divided into two groups based on GT/ASIS (≤1.17 or >1.17) or AGVD (≤86 or >86 mm). Operating time, intraoperative bleeding, and surgical complications were compared between different groups.

RESULTS

A longer average operating time, more intraoperative bleeding, and a higher rate of complications were observed in the group with the highest BMI. The complications included a case of intraoperative femur fracture, a wound hematoma, and a lateral femoral cutaneous nerve injury. The group with higher GT/ASIS had a shorter average operating time, less bleeding, and a lower complication rate than the group with lower GT/ASIS. Moreover, the group with higher AGVD showed a shorter average operating time, less bleeding, and a lower complication rate compared with the group with lower AGVD.

CONCLUSION

Our study suggests that lower BMI and larger GT/ASIS and AGVD are associated with a shorter operating time, less bleeding, and a lower complication rate in DAA total hip replacement. These findings are valuable for clinicians to make the appropriate choice of surgery types for different individuals.

Bariatric surgery operating room time--size matters

BACKGROUND

The goal of this study was to document the relationship between BMI and the components of bariatric surgical operating room (OR) time.

METHODS

The Stanford Translational Research Integrated Database Environment identified all patients who underwent laparoscopic Roux-en-Y gastric bypass procedures at Stanford University Medical Center between May 2008 and November 2013. The 434 patients were divided into 3 groups: group 1 (n = 213) BMI ≥35 to <45 kg/m(2), group 2 (n = 188) BMI ≥45.0 to <60 kg/m(2), and group 3 (n = 33) BMI ≥60 kg/m(2). The primary variable measured was total operating room time, defined as beginning when the patient entered the OR until the moment the patient physically left the OR. Secondary variables were anesthetic induction time, nursing preparation time, operation time, time for emergence from anesthesia, and total length of hospital stay.

RESULTS

Increasing BMI was associated with increased total OR time (group 1 = 202 min, group 2 = 215 min, group 3 = 235 min), mainly due to longer operation time (group 1 = 147 min, group 2 = 154 min, group 3 = 163 min). Anesthetic induction (group 1 = 17 min, group 2 = 18 min, group 3 = 23 min) and emergence times (group 1 = 12 min, group 2 = 12 min, group 3 = 22 min) were also significantly longer in the largest patients.

CONCLUSIONS

Operating room schedules and plans for resource utilization should recognize that the same bariatric procedure will require more time for patients with BMI >60 kg/m(2) than for smaller bariatric patients.

Does Robotic-Assisted Computer Navigation Affect Acetabular Cup Positioning in Total Hip Arthroplasty in the Obese Patient? A Comparison Study

Obese populations present challenges for acetabular cup placement during total hip arthroplasty (THA). This study examines the accuracy of acetabular cup inclination and version in the obese patient with robotic-assisted computer navigation. A total of 105 patients underwent robotic-assisted computer navigation THA with a posterior approach. Groups were divided on body mass index (BMI, kg/m(2)) of <30, 30-35, and >35. There was no statistical difference between the BMI <30 (n=59), BMI 30-35 (n=34) and BMI >35 (n=12) groups for acetabular inclination (P=0.43) or version (P=0.95). Robotic-assisted computer navigation provided accurate and reproducible placement of the acetabular cup within safe zones for inclination and version in the obese patient.

The Effect of BMI on 30 Day Outcomes Following Total Joint Arthroplasty

Hip and knee arthroplasty (THA, TKA) are safe, effective procedures with reliable, reproducible outcomes. We aim to investigate obesity's effect on complications following arthroplasty surgery. Using the American College of Surgeons-National Surgical Quality Improvement Program database, 13,250 subjects were stratified into 5 groups based on BMI and matched for gender, age, surgery type and ASA class. Matched, multivariable generalized linear models adjusting for demographics and comorbidities demonstrated an association between elevated BMI and overall (P<0.001), medical (P=0.005), surgical complications (P<0.001), including superficial (P=0.019) and deep wound infection (P=0.040), return to OR (P=0.016) and time from OR to discharge (P=0.003). Elevated BMI increases risk for post-operative complications following total joint arthroplasty.

The effect of obesity on theatre utilisation time during primary hip and knee replacements

Introduction :

The aim of this study is to assess the effect of body mass index (BMI) and body weight on theatre utilisation time during primary total hip (THR) and knee replacements (TKR).

Methods :

A total of 1859 cases were included (820 THR and 1039 TKR). Patients were divided into groups based on BMI and body weight. The time interval from ‘starting anaesthesia’ to ‘transfer back to recovery’ was used as total theatre time. Hierarchal regression analysis was then used to study the effect of BMI and body weight while controlling the effect of any confounding variables.

Results :

In THR cases, the median theatre time was significantly different between BMI and body weight subgroups (p=0.001). In TKR cases, the median theatre time was more significantly different between weight subgroups (p<0.001) than BMI subgroups (p=0.021). Regression analysis showed that only weight remained a significant predictor (p=0.018) of theatre time in THR cases after controlling for other variables. In TKR cases, body weight and BMI were not predictors of theatre time after controlling for other variables.

Conclusion :

Body weight is a significant predictor of theatre time during THR. Neither weight nor BMI predicted theatre time during TKR.

The effect of body mass index on outcome in total hip arthroplasty: early analysis from the New Zealand Joint Registry

This study assessed the early outcomes of total hip arthroplasty compared with body mass index (BMI). 5357 hip arthroplasties were evaluated. Oxford Scores, revision for any reason and other factors including American Society of Anaesthesiology scores, length of surgery and cementation of components were analyzed. Both a high and a low BMI predicted for worse Oxford Hip Scores. Obese and morbidly obese patients had significantly lower six month Oxford Scores than healthy patients, the lowest survival, were younger than all other groups and had greater proportions with fully un-cemented prostheses. At this early stage, the results show that outcome and early revision are statistically and clinically poorer for obese patients.

Revision THA in obese patients is associated with high re-operation rates at short-term follow-up

We performed a retrospective review of 309 consecutive revision THAs from 2005 to 2009. We identified a subgroup of patients with BMI >35 and compared the operative time, rate of complications, ICU admissions, re-admissions, and re-operations to patients with BMI <35 undergoing revision THA. At a mean follow-up of 36.3 months, there was no significant difference in operative time, perioperative complications, or re-admission rate between the two groups. However, a significantly higher rate of re-operation was observed in the obese group (46% vs. 28%, P=0.015). Obese patients were more likely to undergo reoperation for infection (P=0.017). Patients with high BMI contemplating primary THA should be aware of the potential subsequent complications associated with revision surgery should it become necessary.

Obesity increases operating room times in patients undergoing primary hip arthroplasty: a retrospective cohort analysis

Background. Obesity impacts utilization of healthcare resources. The goal of this study was to measure the relationship between increasing body mass index (BMI) in patients undergoing total hip arthroplasty (THA) with different components of operating room (OR) time.

Methods. The Stanford Translational Research Integrated Database Environment (STRIDE) was utilized to identify all ASA PS 2 or 3 patients who underwent primary THA at Stanford Medical Center from February 1, 2008 through January 1, 2013. Patients were divided into five groups based on the BMI weight classification. Regression analysis was used to quantify relationships between BMI and the different components of total OR time.

Results. 1,332 patients were included in the study. There were no statistically significant differences in age, gender, height, and ASA PS classification between the BMI groups. Normal-weight patients had a total OR time of 138.9 min compared 167.9 min (P < 0.001) for morbidly obese patients. At a BMI > 35 kg/m² each incremental BMI unit increase was associated with greater incremental total OR time increases.

Conclusion. Morbidly obese patients required significantly more total OR time than normal-weight patients undergoing a THA procedure. This increase in time is relevant when scheduling obese patients for surgery and has an important impact on health resource utilization.