B-type natriuretic peptide predicts long-term survival after major non-cardiac surgery

BACKGROUND

The prediction of long-term survival after surgery is complex. Natriuretic peptides can predict short-term postoperative cardiac morbidity and mortality. This study aims to determine the long-term prognostic significance of preoperative B-type natriuretic peptide (BNP) concentration after major non-cardiac surgery.

METHODS

We conducted a prospective single-centre observational cohort study in a West of Scotland teaching hospital. Three hundred and forty-five patients undergoing major non-cardiac surgery were included. The primary endpoint was long-term all-cause mortality.

RESULTS

Overall survival was 67.8% (234/345), with 27 postoperative deaths (within 42 days) and 84 deaths at subsequent follow-up (median follow-up 953 days). A BNP concentration of >87.5 pg ml(-1) best predicted mortality, and the mean survival of patients with an elevated BNP (>87.5 pg ml(-1)) was 731.9 (95% CI 613.6-850.2) days compared with 1284.6 days [(95% CI 1219.3-1350.0), P<0.001] in patients with a BNP<87.5 pg ml(-1). BNP was an independent predictor of survival.

CONCLUSIONS

BNP is an independent predictor of long-term survival after major non-cardiac surgery. A simple preoperative blood test can provide predictive information on future risk of death, and potentially has a role in preoperative risk assessment.

Measurement of process as quality control in the management of acute surgical emergencies

BACKGROUND

Quality of care measured by adverse events cannot address errors of process that have no adverse outcomes. The aim of this study was to determine whether process could be used to assess quality of care and whether process analysis could be used to assess interventions designed to improve quality.

METHODS

A single-centre prospective cohort study was performed over 12 weeks in an acute surgical admission unit. Data were collected prospectively for the first 24 h of admission on three aspects of process: documentation, general management and presentation-specific criteria. After a period of observation, the impact of three interventions (active observation, increasing awareness and issuing a job description) on the mean number of process errors per patient (process score) was compared.

RESULTS

The analysis was based on 566 patients admitted with general surgical pathology. Awareness of being observed failed to improve the process score. Interventions that increased awareness of process reduced the overall process score from 4.79 to 2.38 errors per person (P < 0.001). The mean overall process score in patients with an adverse event was twice that of patients who did not have an adverse event (5.74 (95 per cent confidence interval 4.03 to 7.45) versus 3.43 (3.19 to 3.66)).

CONCLUSION

Process can be measured objectively and used as a measure of quality of care. Interventions to increase awareness reduced process error rates and adverse events.

B-type natriuretic peptide predicts cardiac morbidity and mortality after major surgery

Background

The objective of this study was to determine whether measurement of B-type natriuretic peptide (BNP) concentration before operation could be used to predict perioperative cardiac morbidity.

Methods

A prospective derivation study was performed in high-risk patients undergoing major non-cardiac surgery, with a subsequent validation study. A venous blood sample was taken the day before surgery for measurement of plasma BNP concentration. Screening for cardiac events (non-fatal myocardial infarction and cardiac death) was performed using clinical criteria, cardiac troponin I analysis and serial electrocardiography.

Results

Forty-one patients were recruited to the derivation cohort and 149 to the validation cohort. In the derivation cohort, the median (interquartile range) BNP concentration in the 11 patients who had a postoperative cardiac event was 210 (165–380) pg/ml, compared with 34·5 (14–70) pg/ml in those with no cardiac complications (P &lt; 0·001). In the validation cohort, the median BNP concentration in the 15 patients who had a cardiac event was 351 (127–1034) pg/ml, compared with 30·5 (11–79·5) pg/ml in the remainder (P &lt; 0·001). BNP concentration remained a significant outcome predictor in multivariable analysis (P &lt; 0·001). Using receiver–operator curve analysis it was calculated that a BNP concentration of 108·5 pg/ml best predicted the likelihood of cardiac events, with a sensitivity and specificity of 87 per cent each.

Conclusion

Preoperative serum BNP concentration predicted postoperative cardiac events in patients undergoing major non-cardiac surgery independently of other risk factors.

Should Pre-operative Troponin be a Standard Requirement in Patients Undergoing Major Lower Extremity Amputation?

OBJECTIVES

The objective of this study was to ascertain the benefit of routine pre-operative cardiac troponin I (cTnI) measurement in patients undergoing major lower extremity amputation for critical limb ischaemia.

DESIGN

This was a prospective, blinded observational study.

METHODS

All patients scheduled for lower extremity amputation, without evidence of unstable coronary artery disease were recruited prospectively over a period of 1 year. In addition to routine pre-operative evaluation, a blood sample was taken for measurement of serum cTnI. Post-operative screening was conducted for cardiac events with patients followed up to 6 weeks.

RESULTS

Ten of the 44 patients included suffered a non-fatal myocardial infarction or died from a cardiac cause post-operatively. A rise in pre-operative cTnI was associated with a very poor outcome (two cardiac deaths and one post-operative myocardial infarction) and was the only significant predictor of post-operative cardiac events.

CONCLUSION

Routine pre-operative cTnI measurement may be of use to identify patients at high risk of cardiac complication who would benefit from optimization of cardiac status or in whom surgery could be deferred.

Ten-year experience of carbon dioxide laser ablation as treatment for cutaneous recurrence of malignant melanoma

Background

Cutaneous recurrence of malignant melanoma is distressing for the patient, can be difficult to palliate and is resistant to treatment by conventional methods. Experience with carbon dioxide laser ablation was reviewed to determine the initial efficacy, time to recurrence, number of treatments required and length of palliation achieved.

Methods

Using a departmental database and case notes, a review was carried out of all patients undergoing laser ablation in the authors' unit between September 1992 August 2002.

Results

Forty-two patients received 105 (mean 2·5) treatments. The median time to recurrence was 5·2 (range 1·2–72·0) months. Twenty-three patients were still alive, with a median time from first laser ablation of 5·4 (range 0·5–10·0) years. Nineteen patients had died, a median of 0·8 (range 0·1–5·3) years after the first ablation. Ten of the 23 patients were disease-free for more than 1 year. No limbs were amputated because of failure to control disease.

Conclusion

Laser ablation is a practical and useful method of palliating recurrent cutaneous malignant melanoma.