Prediction of postoperative mortality in elderly patients with hip fracture: are specific and geriatric scores better than general scores?

Predictability of Neutrophil to Lymphocyte Ratio in preoperative elderly hip fracture patients for post-operative short-term complications: a retrospective study

PURPOSE

Neutrophil to Lymphocyte Ratio (NLR) is a simple biomarker of systemic inflammatory response. We investigated predictability of NLR for early adverse outcome after surgery for hip fracture in elderly population.

METHODS

We reviewed a total of 971 elderly patients with hip fracture who underwent emergency surgery between January 2017 and July 2020 in the Department of Orthopaedics Surgery at the Wollongong Hospital. After considering exclusion criteria, data from a total of 834 patients included in our study. Socio-demographic data, NLR in admission, updated Charlson comorbidity index (uCCI), biochemical markers, mortality rate and 15 short term post-operative complications were collected to determine predictability of NLR for post-operative complications and mortality.

RESULTS

After hip surgery, Hospital in-patient case fatality rate was 3.7% (31). In addition, 63.1% (511) of the patients had at least one complication or more. Logistic regression demonstrated that raised NLR (P-value < 0.001, OR 1.05) and uCCI≥4 (P-Value < 0.001, OR 1.75) are associated with post-operative complications. Moreover, decreased haemoglobin was associated with adverse effects (P-value < 0.001, OR 0.97). No association was found for any of these variables with in-patient mortality except for albumin (P-value: 0.03). In addition, despite significant association, ROC analyses showed a low predictability for each of the above variables including NLR (AUC 0.59) for post-operative complications.

CONCLUSIONS

Despite significant association, NLR was unable to prognosticate early adverse outcomes. However, it can be considered as a risk factor in admission for postoperative complications in combination with other risk factors and clinical context.

Inter-rater agreement in pPOSSUM scores of geriatric trauma patients: a prospective evaluation

PURPOSE

Risk prediction models are widely used in the perioperative setting to identify high-risk patients who may benefit from additional care and to aid clinical decision-making. pPOSSUM is such a prediction model, however, little is known about the inter-rater agreement when scoring subjective parameters. This study assessed the inter-rater agreement between clinicians of different specialties and work-level when scoring 30 clinical case reports of geriatric hip fracture patients with pPOSSUM.

METHODS

Eighteen clinicians of the department of Surgery (three specialists, four residents), Anaesthesiology (four specialists, two residents) and Emergency Medicine (three specialists, two residents) who were familiar with the pPOSSUM scoring system were asked to calculate the scores. The kappa statistic and the statistical method of Fleiss were used to analyse inter-rater agreement.

RESULTS

The response rate was 100%. Among surgeons, Anaesthesiologists and Emergency department doctors (ED), the overall mean kappa values were 0.42, 0.08 and 0.20, respectively. Among surgery, anaesthesiology and ED residents the overall mean kappa values were 0.21, 0.33 and 0.37, respectively. Within the department of Surgery, Anaesthesiology and Emergency Medicine the overall mean kappa values were 0.23, 0.12 and 0.22, respectively. An overall mean kappa value of 0.19 was seen among all specialists. All residents had an overall mean kappa value of 0.21 and all clinicians had an overall mean kappa value of 0.21.

CONCLUSION

The overall inter-rater agreement of clinicians and interdisciplinary agreement when scoring geriatric hip fracture patients with pPOSSUM was low and prone to subjectivity in our study. A higher work-experience level did not lead to better agreement. When pPOSSUM is calculated without clinical assessment by the same clinician, caution is advised to prevent over-reliance on the pPOSSUM risk prediction model.

LEVEL OF EVIDENCE

III.

Modifiable factors associated with postoperative atrial fibrillation in older patients with hip fracture in an orthogeriatric care pathway: a nested case–control study

Background

Few data are available regarding post-operative atrial fibrillation (POAF) in non-cardiothoracic surgery, particularly orthopedic surgery. Hence, given the frequent incidence of POAF after surgery and its marked impact, we need to identify modifiable factors associated with POAF after hip fracture surgery in older patients.

Methods

We conducted a nested case–control study in the unit for perioperative geriatric care of an academic hospital in Paris from July 1, 2009 to December 31, 2019, enrolling all consecutive patients aged ≥ 70 years with hip fracture surgery and no history of permanent AF before admission (retrospective analysis of prospectively collected data). Patients with and without POAF were matched 1:5 on 5 baseline characteristics (age, hypertension, diabetes, coronary artery disease, cardiac failure).

Results

Of the 757 patients included, 384 were matched, and 64 had POAF. The incidence of POAF was 8.5%. The mean age was 86 ± 6 years, 298 (78%) patients were female, and the median Charlson Comorbidity Index was 6 (interquartile range 4–8). The median time from surgery to the occurrence of POAF was 2 days (1–4). On multivariable conditional logistic regression analysis (matched cohort), the modifiable factors present at admission associated with POAF were time to surgery > 48 h (odds ratio [OR] = 1.66, 95% confidence interval [1.01–2.81]) and > 2 units of packed red blood cells (OR = 3.94, [1.50–10.03]).

Conclusions

This study provides new information about POAF in older patients with hip fracture surgery, a surgical emergency whose complexity requires multidisciplinary care.

Developing and validating a scoring system for measuring frailty in patients with hip fracture: a novel model for predicting short-term postoperative mortality

Objectives

Frailty is common among patients with hip fracture and may, in part, contribute to the increased risk of mortality and morbidity after hip fracture surgery. This study aimed to develop a novel frailty score for patients with traumatic hip fracture that could be used to predict postoperative mortality as well as facilitate further research into the role of frailty in patients with hip fracture.

Methods

The Orthopedic Hip Frailty Score (OFS) was developed using a national dataset, retrieved from the Swedish National Quality Registry for Hip Fractures, that contained all adult patients who underwent surgery for a traumatic hip fracture in Sweden between January 1, 2008 and December 31, 2017. Candidate variables were selected from the Nottingham Hip Fracture Score, Sernbo Score, Charlson Comorbidity Index, 5-factor modified Frailty Index, as well as the Revised Cardiac Risk Index and ranked based on their permutation importance, with the top 5 variables being selected for the score. The OFS was then validated on a local dataset that only included patients from Orebro County, Sweden.

Results

The national dataset consisted of 126,065 patients. 2365 patients were present in the local dataset. The most important variables for predicting 30-day mortality were congestive heart failure, institutionalization, non-independent functional status, an age ≥85, and a history of malignancy. In the local dataset, the OFS achieved an area under the receiver-operating characteristic curve (95% CI) of 0.77 (0.74 to 0.80) and 0.76 (0.74 to 0.78) when predicting 30-day and 90-day postoperative mortality, respectively.

Conclusions

The OFS is a significant predictor of short-term postoperative mortality in patients with hip fracture that outperforms, or performs on par with, all other investigated indices.

Level of evidence

Level III, Prognostic and Epidemiological.

Lack of Association Between Perioperative Medication and Postoperative Delirium in Hip Fracture Patients in an Orthogeriatric Care Pathway

OBJECTIVES

Units for perioperative geriatric care are playing a growing role in the care of older patients after hip fracture surgery. Postoperative delirium is one of the most common complications after hip fracture, but no study has assessed the impact of therapeutics received during a dedicated orthogeriatric care pathway on its incidence. Our main objective was to assess the association between drugs used in emergency, operating, and recovery departments and postoperative delirium during the acute stay.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

All patients ≥70 years old admitted for hip fracture to the emergency department and hospitalized in our unit for perioperative geriatric care after hip fracture surgery under general anesthesia between July 2009 and December 2019 in an academic hospital in Paris.

METHODS

Demographic, clinical, and biological data and all medications administered pre-, peri-, and postoperatively were prospectively collected by 3 geriatricians. Postoperative delirium in the unit for perioperative geriatric care was assessed by using the confusion assessment method scale. Logistic regression analysis was used to assess variables independently associated with postoperative delirium.

RESULTS

A total of 490 patients were included [mean (SD) age 87 (6) years]; 215 (44%) had postoperative delirium. The occurrence was not associated with therapeutics administered during the dedicated orthogeriatric care pathway. Probability of postoperative delirium was associated with advanced age [>90 years, odds ratio (OR) 2.03, 95% confidence interval (CI) 1.07-3.89], dementia (OR 3.51, 95% CI 2.14--5.82), depression (OR 1.85, 95% CI 1.14-3.01), and preoperative use of beta-blockers (OR 1.75, 95% CI 1.10-2.79).

CONCLUSIONS AND IMPLICATIONS

No emergency or anesthetic drugs were significantly associated with postoperative delirium. Further studies are needed to demonstrate a possible causal link between preoperative use of beta-blockers and postoperative delirium.

The ability of comorbidity indices to predict mortality in an orthopedic setting: a systematic review

BACKGROUND

Several comorbidity indices have been created to estimate and adjust for the burden of comorbidity. The objective of this systematic review was to evaluate and compare the ability of different comorbidity indices to predict mortality in an orthopedic setting.

METHODS

A systematic search was conducted in Embase, MEDLINE, and Cochrane Library. The search were constructed around two primary focal points: a comorbidity index and orthopedics. The last search were performed on 13 June 2019. Eligibility criteria were participants with orthopedic conditions or who underwent an orthopedic procedure, a comparison between comorbidity indices that used administrative data, and reported mortality as outcome. Two independent reviewers screened the studies using Covidence. The area under the curve (AUC) was chosen as the primary effect estimate.

RESULTS

Of the 5338 studies identified, 16 met the eligibility criteria. The predictive ability of the different comorbidity indices ranged from poor (AUC < 0.70) to excellent (AUC ≥ 0.90). The majority of the included studies compared the Elixhauser Comorbidity Index (ECI) and the Charlson Comorbidity Index (CCI). In-hospital mortality was reported in eight studies reporting AUC values ranging from 0.70 to 0.92 for ECI and 0.68 to 0.89 for CCI. AUC values were generally lower for all other time points ranging from 0.67 to 0.78. For 1-year mortality the overall effect size ranging from 0.67 to 0.77 for ECI and 0.69 to 0.77 for CCI.

CONCLUSION

The results of this review indicate that the ECI and CCI can equally be used to adjust for comorbidities when analyzing mortality in an orthopedic setting.

TRIAL REGISTRATION

The protocol for this systematic review was registered on PROSPERO, the International Prospective Register of Systematic Reviews on 13 June 2019 and can be accessed through record ID 133,871.

Predicting 30-Day and 180-Day Mortality in Elderly Proximal Hip Fracture Patients: Evaluation of 4 Risk Prediction Scores at a Level I Trauma Center

This study evaluated the use of risk prediction models in estimating short- and mid-term mortality following proximal hip fracture in an elderly Austrian population. Data from 1101 patients who sustained a proximal hip fracture were retrospectively analyzed and applied to four models of interest: Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM), Charlson Comorbidity Index, Portsmouth-POSSUM and the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP^®) Risk Score. The performance of these models according to the risk prediction of short- and mid-term mortality was assessed with a receiver operating characteristic curve (ROC). The median age of participants was 83 years, and 69% were women. Six point one percent of patients were deceased by 30 days and 15.2% by 180 days postoperatively. There was no significant difference between the models; the ACS-NSQIP had the largest area under the receiver operating characteristic curve for within 30-day and 180-day mortality. Age, male gender, and hemoglobin (Hb) levels at admission <12.0 g/dL were identified as significant risk factors associated with a shorter time to death at 30 and 180 days postoperative (p < 0.001). Among the four scores, the ACS-NSQIP score could be best-suited clinically and showed the highest discriminative performance, although it was not specifically designed for the hip fracture population.

External validation of the Almelo Hip Fracture Score, a prediction model for early mortality following hip fracture surgery

PURPOSE

Early mortality (< 30 days) in hip fracture patients is as high as 9.6%. Several risk assessment tools have been developed to identify patients at high risk for early mortality. Among them, the Almelo Hip Fracture Score (AHFS) was developed recently and showed promising results. Until now, this tool has not been validated; therefore, we aim to perform an external validation of the AHFS.

METHODS

On admission, AHFS variables were prospectively collected. The prospectively collected data were used retrospectively to externally validate the AHFS in a cohort of hip fracture patients that were admitted to a hospital in Delft (Delft cohort). The AHFS score was retrospectively calculated for all hip fracture patients meeting the inclusion criteria. The characteristics of the Delft Cohort, AHFS score, sensitivity, specificity, positive predictive value, negative predictive value, and area under the curve were calculated and compared to the original Almelo cohort, in which the AHFS was developed.

RESULTS

422 patients of 70 years and older were included. Mortality within 30 days was 7.6% and similar to the 7.5% observed in the Almelo cohort. For the high-risk cut-off point, specificity was 95.4% in the Delft Cohort vs. 92.5% in the Almelo Cohort, and sensitivity for the low-risk cut-off point was 75.9 vs. 78.1% in the Almelo Cohort. The area under the ROC curve was 0.70 (95% CI 0.60-0.79) compared to 0.82 in the Almelo cohort.

CONCLUSIONS

The validity of the score was acceptable and comparable to the values in the Almelo cohort. This score might be used to identify patients at high risk for early mortality.

Novel biomarkers for prediction of outcome in hip fracture patients-An exploratory study

BACKGROUND

Little is known about the value of biomarkers for prognostication in hip fracture patients. The main objective of the present study was to assess if biomarkers add useful information to an existing risk score for prediction of 30-day mortality in patients suffering from out of hospital hip fractures.

METHODS

In a prospective observational single centre study, association between plasma concentration of ninety-two biomarkers at admission and 30-day mortality was analysed using logistic regression adjusted for risk factors included in Nottingham Hip Fracture Score (NHFS). Biomarkers associated with the outcome in the adjusted analysis were further evaluated by calculating the net reclassification improvement (NRI) and the change in area under the receiver operating characteristics curve (AUC) relative to the NHFS.

RESULTS

997 patients were included. Sixty-two patients died within 30 days (6.2%). Eleven biomarkers were associated with 30-day mortality in adjusted analysis. Of these biomarkers Growth Differentiation Factor-15 (GDF-15) had NRI for the primary outcome (12.1%; 95% CI: 1.2-23.3) and Carbohydrate Antigen 125 (CA-125) improved the AUC relative to NHFS (improvement: 0.05; 95% CI: 0.01-0.10, P = .027). Both CA-125 and GDF-15 improved the AUC for a composite outcome of 30-day mortality and cardiovascular complications.

CONCLUSIONS

Adding GDF-15 or CA-125 to the Nottingham Hip Fracture Score improves the discrimination with regard to predicting 30-day mortality and may help to identify a subgroup of hip fracture patients with a particularly poor prognosis. The value of these biomarkers should be explored in further studies to confirm clinical utility.

Attributable Mortality of Hip Fracture in Older Patients: A Retrospective Observational Study

Hip fracture (HF) in older patients is associated with a high six-month mortality rate. Several clinical conditions may affect outcome, including baseline characteristics, co-existing acute illnesses, perioperative factors, and postoperative complications. Our primary objective was to estimate the respective effect of these four domains on six-month mortality after HF. A retrospective observational study using a monocentric cohort of older patients was conducted. All patients ≥ 70 years old admitted to the emergency department for HF and hospitalized in our perioperative geriatric care unit from June 2009 to September 2018 were included. Among 1015 included patients, five (0.5%) were lost to follow-up, and 1010 were retained in the final analysis (mean age 86 ± 6 years). The six-month mortality rate was 14.8%. The six-month attributable mortality estimates were as follows: baseline characteristics (including age, gender, comorbidities, autonomy, type of fracture): 62.4%; co-existing acute illnesses (including acute events present before surgery that could result from the fracture or cause it): 0% (not significantly associated with six-month mortality); perioperative factors (including blood transfusion and delayed surgery): 12.3%; severe postoperative complications: 11.9%. Baseline characteristics explained less than two-thirds of the six-month mortality after HF. Optimizing patients care by improving management of perioperative factors and thus decreasing postoperative complications, could reduce by a maximum of one quarter of the six-month mortality rate after HF.

Hip fracture mortality: Predictive models

The preoperative estimation of the risk of mortality after a hip fracture is very useful to plan time of surgery and perioperative care, inform patients and families about the prognosis and allows comparisons between different units. Different models have been developed to stratify mortality risk, but they show heterogeneity in terms of type of population and variables included, monitoring the time and statistical methods used, which makes it difficult to establish comparisons between them. The vast majority of them are awaiting external validation in populations different from those in which they were originally proposed. So far, the Nottingham Hip Fracture Score (NHFS) and the Orthopaedic Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (O-POSSUM) are the most commonly used models. The NHFS is simpler and faster to apply, and by not including intraoperative variables can be used at the time of admission.

Prediction of postoperative mortality in elderly patient with hip fractures: a single-centre, retrospective cohort study

Background

Elderly patients are at high risk for postoperative complications and increased mortality after hip fracture (HF) surgery due to frailty and co-morbidities. The prediction of postoperative outcome could be used for clinical decision making. A reliable score to predict postoperative mortality after HF surgery in this sub-population remains unavailable.

Methods

A single-centre retrospective cohort study was performed in 782 patients who were operated on for HF. Receiver Operating Characteristic (ROC)-curves were used to analyse the performance of gender, age, neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) at admission (D₀) as prognostic factors, alone or combined with the PreOperative Score to predict PostOperative Mortality (POSPOM) in univariate and multivariate linear regression models.

Results

No correlation between gender, age, NLR D₀ or CRP D₀ and postoperative, intra-hospital mortality was found. The Area Under the ROC-curve (AUC) for age, male gender, NLR and CRP were 0.61 [95% confidence interval (CI) = 0.45–0.61], 0.56 [95% CI = 0.42–0.56], 0.47 [95% CI = 0.29–0.47] and 0.49 [95% CI = 0.31–0.49] respectively. Combination with the POSPOM score did not increase its discriminative capacity as neither age (AUC = 0.69, 95% CI = 0.54–0.69), gender (AUC = 0.72, 95% CI = 0.58–0.72), NLR D₀ (AUC = 0.71, 95% CI = 0.56–0.71), nor the CRP D₀ (AUC = 0.71, 95% CI = 0.58–0.71) improved the POSPOM performance.

Conclusions

Neither age, gender, NLR D₀ nor CRP D₀ are suitable parameters to predict postoperative, intra-hospital mortality in elderly patients undergoing surgery for HF.

Accuracy of the Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity score and the Nottingham risk score in hip fracture patients in Sweden - A prospective observational study

BACKGROUND

Little is known about accuracy of common risk prediction scores in elderly patients suffering from hip fractures. The objective of this study was to investigate accuracy of the Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) score, Portsmouth-POSSUM (P-POSSUM) score and the Nottingham Hip Fracture Score (NHFS) for prediction of mortality and morbidity in this patient group.

METHODS

This was a prospective single centre observational study on 997 patients suffering out-of-hospital cervical, trochanteric or subtrochanteric fracture of the neck of the femur. Calibration and discrimination was assessed by calculating the ratio of observed to expected events (O:E) and areas under receiver operating characteristics curves (ROC).

RESULTS

The 30-day mortality was 6.2% and complications, as defined by POSSUM, occurred in 41% of the patients. Overall O:E ratios for POSSUM, P-POSSUM and NHFS scores for 30-day mortality were 0.90, 0.98, and 0.79 respectively. The models underestimated mortality in the lower risk bands and overestimated mortality in the higher risk bands. In contrast, POSSUM predicted morbidity well with O:E ratios close to unity in most risk bands. The areas under the ROC curves for the scoring systems was 0.60-0.67.

CONCLUSION

The POSSUM score and NHFS show moderate calibration and poor discrimination in this cohort. The results suggest that mortality and morbidity in hip fracture patients are largely dependent on factors that are not included in these scores.

Retrospective Evaluation of a Restrictive Transfusion Strategy in Older Adults with Hip Fracture

OBJECTIVES

To compare the association between a restrictive transfusion strategy and cardiovascular complications during hospitalization for hip fracture with the association between a liberal transfusion strategy and cardiovascular complications, accounting for all transfusions from the emergency department to postacute rehabilitation settings.

DESIGN

Retrospective study.

SETTING

Perioperative geriatric care unit.

PARTICIPANTS

All individuals aged 70 and older admitted to the emergency department for hip fracture and hospitalized in our perioperative geriatric care unit (N=667; n=193 in the liberal transfusion group, n=474 in the restrictive transfusion group) from July 2009 to April 2016.

INTERVENTION

A restrictive transfusion strategy (hemoglobin level threshold ≥8 g/dL or symptoms) used from January 2012 to April 2016 was compared with the liberal transfusion strategy (hemoglobin level threshold ≥10 g/dL) used from July 2009 to December 2011.

MEASUREMENTS

Primary endpoint was in-hospital acute cardiovascular complications (heart failure, myocardial infarction, atrial fibrillation or stroke).

RESULTS

The change to a restrictive transfusion strategy was associated with fewer acute cardiovascular complications (odds ratio=0.45, 95% confidence interval (CI)=0.31-0.67, p<.001), without any noticeable difference in in-hospital or 6-month mortality. The change also led to a reduction in packed red blood cell units used per participant (median 1, interquartile range (IQR) 0-2 in restrictive vs median 2, IQR 0-3 in liberal transfusion strategy, P<.001). In rehabilitation settings, the frequency of transfusion was greater with the restrictive transfusion strategy than the liberal transfusion strategy (18% vs 9%, P<.001).

CONCLUSION

A restrictive transfusion strategy in older adults with hip fracture was found to be safe and was associated with fewer cardiovascular complications but more transfusions in rehabilitation settings. Prospective studies are needed to confirm these findings.

Interdisciplinary Care Model Independently Decreases Use of Critical Care Services After Corrective Surgery for Adult Degenerative Scoliosis

OBJECTIVE

Interdisciplinary management of elderly patients requiring spine surgery has been shown to improve short- and long-term outcomes. The aim of this study was to determine whether an interdisciplinary team approach mitigates use of intensive care unit (ICU) resources.

METHODS

A unique comanagement model for elderly patients undergoing lumbar fusion surgery was implemented at a major academic medical center. The Peri-operative Optimization of Senior Health Program (POSH) was launched with the aim of improving outcomes in elderly patients (>65 years old) undergoing complex lumbar spine surgery. In this model, a geriatrician evaluates elderly patients preoperatively, comanages daily throughout hospital course, and coordinates multidisciplinary rehabilitation, along with the neurosurgical team. We retrospectively reviewed the first 100 cases after the initiation of the POSH protocol and compared them with the immediately preceding 25 cases to assess the rates of ICU transfer and independent predictors of ICU admission.

RESULTS

A total of 125 patients undergoing lumbar decompression and fusion surgery were enrolled in this pilot program. Baseline characteristics and intraoperative variables, as well as number of fusion levels and duration of surgery, were similar between both cohorts. There was a significant difference in the use of ICU services (ICU admission rates) between both cohorts, with the non-POSH cohort having a 3-fold increase compared with the POSH cohort (P < 0.0001). In a multivariate analysis, lack of an interdisciplinary comanagement team approach was an independent predictor for ICU transfers in elderly patients undergoing corrective surgery (odds ratio 8.51, 95% confidence interval 2.972-24.37, P < 0.0001).

CONCLUSIONS

Our study suggests that an interdisciplinary comanagement model between geriatrics and neurosurgery is independently associated with reduced use of critical care services.