Wen Kwang Lim

The prognostic value of pre-operative and post-operative B-type natriuretic peptides in patients undergoing noncardiac surgery: B-type natriuretic peptide and N-terminal fragment of pro-B-type natriuretic peptide: A systematic review and individual patient data meta-analysis

OBJECTIVES The objective of this study was to determine whether measuring post-operative B-type natriuretic peptides (NPs) (i.e., B-type natriuretic peptide [BNP] and N-terminal fragment of proBNP [NT-proBNP]) enhances risk stratification in adult patients undergoing noncardiac surgery, in whom a pre-operative NP has been measured. BACKGROUND Pre-operative NP concentrations are powerful independent predictors of perioperative cardiovascular complications, but recent studies have reported that elevated post-operative NP concentrations are independently associated with these complications. It is not clear whether there is value in measuring post-operative NP when a pre-operative measurement has been done. METHODS We conducted a systematic review and individual patient data meta-analysis to determine whether the addition of post-operative NP levels enhanced the prediction of the composite of death and nonfatal myocardial infarction at 30 and ≥180 days after surgery. RESULTS Eighteen eligible studies provided individual patient data (n = 2,179). Adding post-operative NP to a risk prediction model containing pre-operative NP improved model fit and risk classification at both 30 days (corrected quasi-likelihood under the independence model criterion: 1,280 to 1,204; net reclassification index: 20%; p < 0.001) and ≥180 days (corrected quasi-likelihood under the independence model criterion: 1,320 to 1,300; net reclassification index: 11%; p = 0.003). Elevated post-operative NP was the strongest independent predictor of the primary outcome at 30 days (odds ratio: 3.7; 95% confidence interval: 2.2 to 6.2; p < 0.001) and ≥180 days (odds ratio: 2.2; 95% confidence interval: 1.9 to 2.7; p < 0.001) after surgery. CONCLUSIONS Additional post-operative NP measurement enhanced risk stratification for the composite outcomes of death or nonfatal myocardial infarction at 30 days and ≥180 days after noncardiac surgery compared with a pre-operative NP measurement alone.

Incidence of post-operative troponin I rises and 1-year mortality after emergency orthopaedic surgery in older patients

OBJECTIVES to determine the incidence of post-operative troponin I rises and its association with 1-year all-cause mortality and cardiac events after emergency orthopaedic-geriatric surgery, which has not been studied before. METHODS one hundred and two patients over the age of 60 were recruited and followed up at 1 year. All consented to serial troponin I measurements peri-operatively. RESULTS the incidence of a troponin I rise post-operatively was 52.9%. Post-operative acute myocardial infarction was diagnosed in 9.8% and at 1 year, 70% of these patients were dead. At 1 year, 32.4% (33/102) had sustained a cardiac event (myocardial infarction, congestive cardiac failure, atrial fibrillation or major arrhythmia) and using multivariate analysis, post-operative troponin rise (OR 3.9, 95% CI 1.4-10.7, P = 0.008) was an independent predictor of this. Half of the patients with a troponin rise had a cardiac event compared to 18.8% without a rise. All-cause mortality was 20.6% at 1 year; 37% with an associated post-operative troponin rise died versus 2.1% without a rise (P < 0.0001). Using multivariate analysis, only two factors were associated with 1-year all-cause mortality: post-operative troponin rise (OR 12.0, 95% CI 1.4-104.8, P = 0.025) and sustaining a post-operative in-hospital cardiac event (OR 6.6, 95% CI 1.7-25.6, P = 0.006). Furthermore, patients with higher troponin levels had significantly worse survival. CONCLUSIONS there is a high incidence of post-operative troponin I rises in older patients undergoing emergency orthopaedic surgery with 1-year mortality and cardiac events being significantly increased in these patients. Future studies are needed to determine whether any intervention can improve outcome for these patients.

Postoperative B-type Natriuretic Peptide for Prediction of Major Cardiac Events in Patients Undergoing Noncardiac Surgery: Systematic Review and Individual Patient Meta-analysis.

Background:It is unclear whether postoperative B-type natriuretic peptides (i.e., BNP and N-terminal proBNP) can predict cardiovascular complications in noncardiac surgery. Methods:The authors undertook a systematic review and individual patient data meta-analysis to determine whether postoperative BNPs predict postoperative cardiovascular complications at 30 and 180 days or more. Results:The authors identified 18 eligible studies (n = 2,051). For the primary outcome of 30-day mortality or nonfatal myocardial infarction, BNP of 245 pg/ml had an area under the curve of 0.71 (95% CI, 0.64–0.78), and N-terminal proBNP of 718 pg/ml had an area under the curve of 0.80 (95% CI, 0.77–0.84). These thresholds independently predicted 30-day mortality or nonfatal myocardial infarction (adjusted odds ratio [AOR] 4.5; 95% CI, 2.74–7.4; P < 0.001), mortality (AOR, 4.2; 95% CI, 2.29–7.69; P < 0.001), cardiac mortality (AOR, 9.4; 95% CI, 0.32–254.34; P < 0.001), and cardiac failure (AOR, 18.5; 95% CI, 4.55–75.29; P < 0.001). For greater than or equal to 180-day outcomes, natriuretic peptides independently predicted mortality or nonfatal myocardial infarction (AOR, 3.3; 95% CI, 2.58–4.3; P < 0.001), mortality (AOR, 2.2; 95% CI, 1.67–86; P < 0.001), cardiac mortality (AOR, 2.1; 95% CI, 0.05–1,385.17; P < 0.001), and cardiac failure (AOR, 3.5; 95% CI, 1.0–9.34; P = 0.022). Patients with BNP values of 0–250, greater than 250–400, and greater than 400 pg/ml suffered the primary outcome at a rate of 6.6, 15.7, and 29.5%, respectively. Patients with N-terminal proBNP values of 0–300, greater than 300–900, and greater than 900 pg/ml suffered the primary outcome at a rate of 1.8, 8.7, and 27%, respectively. Conclusions:Increased postoperative BNPs are independently associated with adverse cardiac events after noncardiac surgery.

Additional exercise does not change hospital or patient outcomes in older medical patients: a controlled clinical trial.

QUESTION What are the effects of additional exercise on hospital and patient outcomes for acutely-hospitalised older medical patients? DESIGN Controlled clinical trial. PARTICIPANTS 236 Patients aged 65 or older admitted to an acute care hospital with a medical illness between October 2002 and July 2003. INTERVENTION The experimental group received usual care plus an individually tailored exercise program administered twice daily from hospital admission to discharge. The control group received usual care only. OUTCOME MEASURES The primary outcome was discharge destination. Secondary outcomes were measures of activity limitation (Barthel Index, Timed Up and Go, Functional Ambulation Classification), length of stay, and adverse events. RESULTS There was no significant effect of the additional exercise program on any outcome. There were no significant differences between groups for the proportion of the patients discharged to home (RR 0.99, 95% CI 0.86 to 1.14) or inpatient rehabilitation (RR 0.76, 95% CI 0.30 to 1.51) or for measures of activity limitation at hospital discharge. A one day difference in length of stay was identified between groups but this difference was not significant (p = 0.45). There were no significant differences between groups for adverse events: 28-day readmission (RR 1.10, 95% CI 0.65 to 1.86), patient mortality (RR 1.15, 95% CI 0.16 to 8.0), intensive care admission (RR 0.16, 95% CI 0.01 to 3.13) and falls (RR 0.69, 95% CI 0.17 to 2.81). CONCLUSION Additional physiotherapy intervention during hospitalisation did not significantly improve hospital or patient outcomes.

People aged over 75 in atrial fibrillation on warfarin: the rate of major hemorrhage and stroke in more than 500 patient-years of follow-up.

Objectives: To determine the incidence of major hemorrhage and stroke in people aged 76 and older with atrial fibrillation on adjusted‐dose warfarin who had been recently been admitted to hospital.Objectives: To determine the incidence of major hemorrhage and stroke in people aged 76 and older with atrial fibrillation on adjusted-dose warfarin who had been recently been admitted to hospital. Design: A retrospective observational cohort study. Setting: A major healthcare network involving four tertiary hospitals. Participants: Two hundred thirty-five patients aged 76 and older admitted to a major healthcare network between July 1, 2001, and June 30, 2002, with atrial fibrillation on warfarin were enrolled. Measurements: Information regarding major bleeding episodes, strokes, and warfarin use was obtained from patients, relatives, primary physicians, and medical records. Results: Two hundred twenty-eight patients (42% men) with a mean age of 81.1 (range 76–94) were included in the analysis. Total follow-up on warfarin was 530 years (mean 28 months). There were 53 major hemorrhages, for an annual rate of 10.0%, including 24 (45.3%) life-threatening and five (9.4%) fatal bleeds. The annual stroke rate after initiation of warfarin was 2.6%. Conclusion: The rate of major hemorrhage was high in this old, frail group, but excluding fatalities, resulted in no long-term sequelae, and the stroke rate on warfarin was low, demonstrating how effective warfarin treatment is.

Usefulness of N-terminal pro-brain natriuretic peptide to predict postoperative cardiac complications and long-term mortality after emergency lower limb orthopedic surgery.

After emergency orthopedic-geriatric surgery, cardiac complications are an important cause of morbidity and mortality. The utility of N-terminal pro-brain natriuretic peptide (NT-pro-BNP) for the prediction of cardiac complications and mortality was evaluated. NT-pro-BNP was tested pre- and postoperatively in 89 patients >60 years of age. They were followed for 2 years for cardiac complications (defined as acute myocardial infarction, congestive cardiac failure, atrial fibrillation or major arrhythmia) or death. Receiver operating characteristic curves were constructed to determine the optimal discriminatory level for cardiac events and death using NT-pro-BNP. Twenty-three patients (25.8%) sustained an in-hospital postoperative cardiac complication. Total all-cause mortality was 3 of 89 (3.4%) in hospital, 21 of 89 (23.6%) at 1 year, and 27 of 89 (30.3%) at 2 years. Median preoperative and postoperative NT-pro-BNP levels were higher in patients who had an in-hospital cardiac event compared to those without (387 vs 1,969 pg/ml, p <0.001; and 676 vs 7,052 pg/ml, p <0.001 respectively). The optimal discriminatory level for preoperative NT-pro-BNP was 842 pg/ml and that for postoperative NT-pro-BNP was 1,401 pg/ml for the prediction of in-hospital cardiac events and 1- and 2-year mortality. Preoperative NT-pro-BNP >/=842 pg/ml (odds ratio 11.6, 95% confidence interval 2.1 to 65.0, p = 0.005) was an independent predictor of in-hospital cardiac complications using multivariate analysis and pre- and postoperative NT-pro-BNP levels were independent predictors of 2-year cardiovascular events. Patients who had preoperative NT-pro-BNP >/=842 pg/ml or postoperative NT-pro-BNP >/=1,401 pg/ml had significantly worse survival using log-rank testing (p <0.001) and these variables independently predicted 2-year mortality. In conclusion, increase pre- and postoperative NT-pro-BNP levels are independent predictors of in-hospital cardiac events and 1- and 2-year mortality in older patients undergoing emergency orthopedic surgery.

Medical problems in hip fracture patients

Increasing number of older patients are admitted to hospital with hip fractures. This review evaluates the common medical problems that arise as a consequence of having a hip fracture. Older patients with fractures commonly have co-morbidities that require evaluation prior to and after surgery. Joint acute orthopaedic–geriatric units have been established to provide comprehensive orthopaedic and medical care with some studies showing a reduction in postoperative complications and mortality. Recommendations surrounding the care of the older orthopaedic patient include early surgical fixation, the use of prophylactic antibiotics and thromboembolic prophylaxis, good perioperative pain control to improve ambulation, delirium detection and management to decrease the risk complications, such as institutionalisation, the avoidance of malnutrition, urinary tract management, osteoporosis management and the promotion of early mobilisation to improve functional recovery. Physicians are well placed to manage these patients with orthopaedic surgeons during the perioperative period. Sufficient evidence exists for most recommendations for fracture patients, but further research is needed in most areas.

Description of an orthopedic–geriatric model of care in Australia with 3 years data

Aim:  Orthopedic–geriatric units have been established worldwide to improve the care of older patients admitted with fractures. This study describes one type of orthopedic–geriatric model which has been implemented in Victoria, Australia, named the Orthopedic Aged Care and Rehabilitation Service (OARS) and evaluates patient characteristics and outcomes including inpatient mortality.

N-Terminal Pro-Brain Natriuretic Peptide and Angiotensin-Converting Enzyme-2 Levels and Their Association With Postoperative Cardiac Complications After Emergency Orthopedic Surgery

The prognostic usefulness of the cardiac biomarkers N-terminal pro-brain natriuretic peptide (NT-proBNP) and angiotensin-converting enzyme 2 (ACE-2), in predicting adverse cardiac outcomes after orthopedic surgery is not well studied. The aim of our study was to determine the usefulness of perioperative NT-proBNP and ACE-2 for predicting cardiac events after emergency orthopedic surgery. The perioperative NT-proBNP and ACE-2 levels were determined in 187 consecutive patients aged >60 years who underwent orthopedic surgery with 1 year of follow-up for any cardiac complications (defined as acute myocardial infarction, congestive cardiac failure, atrial fibrillation, or major arrhythmia) and death. Of the 187 patients, 20 (10.7%) sustained an in-hospital postoperative cardiac complication. The total all-cause in-hospital and 1-year mortality rate was 1.6% (3 of 187) and 8.6% (16 of 187), respectively. The median preoperative and postoperative NT-proBNP level was greater in patients who sustained an in-hospital cardiac event than in those who had not (386 vs 2,273 pg/ml, p <0.001, and 605 vs 4,316 pg/ml, p <0.001, respectively). Similarly, the postoperative median ACE-2 levels were significantly greater in the patients with an in-hospital cardiac event than in those without (25.3 vs 39.5 pmol/ml/min, p = 0.012). A preoperative NT-proBNP level of ≥741 pg/ml (odds ratio 4.5, 95% confidence interval 1.3 to 15.2, p = 0.017), postoperative troponin elevation (odds ratio 4.9, 95% confidence interval 1.3 to 18.9, p = 0.022), and number of co-morbidities (odds ratio 1.8, 95% confidence interval 1.2 to 2.8, p = 0.009) independently predicted in-hospital cardiac complications on multivariate analysis. The pre- and postoperative NT-proBNP level independently predicted 1-year cardiovascular complications but not the ACE-2 levels. In conclusion, elevated perioperative NT-proBNP predicted in-hospital and 1-year cardiac events in an emergency orthopedic population but the ACE-2 levels did not, which requires additional study for validation.

Implementing evidence-based guidelines: inpatient management of chronic obstructive pulmonary disease

Background:  Evidence‐based guidelines exist to guide inpatient management of chronic obstructive pulmonary disease (COPD) exacerbations, but we do not know how well these recommendations are adhered to.