Implication of Major Adverse Postoperative Events and Myocardial Injury on Disability and Survival: A Planned Subanalysis of the ENIGMA-II Trial.

BACKGROUND: Globally, >300 million patients have surgery annually, and ≤20% experience adverse postoperative events. We studied the impact of both cardiac and noncardiac adverse events on 1-year disability-free survival after noncardiac surgery. METHODS: We used the study cohort from the Evaluation of Nitrous oxide in Gas Mixture of Anesthesia (ENIGMA-II) trial, an international randomized trial of 6992 noncardiac surgical patients. All were ≥45 years of age and had moderate to high cardiac risk. The primary outcome was mortality within 1 postoperative year. We defined 4 separate types of postoperative adverse events. Major adverse cardiac events (MACEs) included myocardial infarction (MI), cardiac arrest, and myocardial revascularization with or without troponin elevation. MI was defined using the third Universal Definition and was blindly adjudicated. A second cohort consisted of patients with isolated troponin increases who did not meet the definition for MI. We also considered a cohort of patients who experienced major adverse postoperative events (MAPEs), including unplanned admission to intensive care, prolonged mechanical ventilation, wound infection, pulmonary embolism, and stroke. From this cohort, we identified a group without troponin elevation and another with troponin elevation that was not judged to be an MI. Multivariable Cox proportional hazard models for death at 1 year and assessments of proportionality of hazard functions were performed and expressed as an adjusted hazard ratio (aHR) and 95% confidence intervals (CIs). RESULTS: MACEs were observed in 469 patients, and another 754 patients had isolated troponin increases. MAPEs were observed in 631 patients. Compared with control patients, patients with a MACE were at increased risk of mortality (aHR, 3.36 [95% CI, 2.55-4.46]), similar to patients who suffered a MAPE without troponin elevation (n = 501) (aHR, 2.98 [95% CI, 2.26-3.92]). Patients who suffered a MAPE with troponin elevation but without MI had the highest risk of death (n = 116) (aHR, 4.29 [95% CI, 2.89-6.36]). These 4 types of adverse events similarly affected 1-year disability-free survival. CONCLUSIONS: MACEs and MAPEs occur at similar frequencies and affect survival to a similar degree. All 3 types of postoperative troponin elevation in this analysis were associated, to varying degrees, with increased risk of death and disability.

Improved performance on cardiopulmonary exercise testing following DDDR pacemaker adjustment: a case report.

We report a case of improved cardiopulmonary exercise (CPX) test outcomes measured 48 h after initial CPX testing and immediately after alterations were made to the settings of a dual chamber, dual sensing pacemaker with exercise detection. The changes allowed successful abdominal surgery to be completed.

Cardiopulmonary exercise testing predicts 5 yr survival after major surgery.

BACKGROUND: Cardiopulmonary exercise testing (CPET) is used to assess perioperative risk in surgical patients. While previous studies have looked at short-term outcomes, this paper explores the ability of CPET to predict 5 yr survival after major surgery. METHODS: Over a period (1996-2009), 1725 patients referred for CPET subsequently underwent major surgery. Breath-by-breath data derived during each patient's CPET was processed using customized software to extract variables likely to impact on survival. Initial analysis examined the predictive power of single variables. Subsequently, Bayesian model averaging (BMA) was used to construct a multivariate model defining the association between CPET data and 5 yr survival. RESULTS: Six hundred and sixteen (36%) of the study patients died. Single variables were not significantly associated with 5 yr postoperative survival. BMA indicated the following major predictors of 5 yr survival: patient gender; type of surgery, and forced vital capacity. Four variables derived at the patient's anaerobic threshold were weaker predictors. These were end-tidal oxygen concentration, respiratory exchange ratio, oxygen consumption per unit body weight, and oxygen consumption per heart beat. The resulting model was then used to divide patients into low-, medium-, or high-risk categories, and 5 yr survival for each category was 87.8; 75.8, and 53.8% respectively. Survival was independent of patient age. CONCLUSIONS: Multivariate analysis and model generation techniques can be applied to CPET data to predict 5 yr survival after major surgery more accurately than is possible with single variable analysis.

Fiduciary disclosure of medical mistakes: the duty to promptly notify patients of adverse health care events.

Fiduciary obligations are imposed by the common law to ensure that a person occupying a societal role with a high potential for the manipulation of vulnerable persons exercises utmost good faith. Australian law has recognised that the doctor-patient relationship, while not wholly fiduciary, has fiduciary aspects. Amongst such duties are those prohibiting sexual or financial abuse of patients or disclosure without express authority of confidential information. One important consequence of attaching such fiduciary duties to the doctor-patient relationship is that the onus of proof falls not upon the vulnerable party (the patient), but upon the doctor (to disprove the allegation). Another is that consent cannot be pleaded as an absolute defence. In this article the authors advocate that the law should now accept that the fiduciary obligations of the doctor-patient relationship extend to creating a legal duty that any adverse health care event be promptly reported to the patient involved. The reasons for creating such a presumption, as well as its elements and exceptions, are explained.