Anesthetic Management and One-Year Mortality After Noncardiac Surgery

Abstract

Little is known about the effect of anesthetic management on long-term outcomes. We designed a prospective observational study of adult patients undergoing major noncardiac surgery with general anesthesia to determine if mortality in the first year after surgery is associated with demographic, preoperative clinical, surgical, or intraoperative variables. One-year mortality was 5.5% in all patients (n = 1064) and 10.3% in patients > or =65 yr old (n=243). Multivariate Cox Proportional Hazards modeling identified three variables as significant independent predictors of mortality: patient comorbidity (relative risk, 16.116; P <0.0001), cumulative deep hypnotic time (Bispectral Index <45) (relative risk=1.244/h; P=0.0121) and intraoperative systolic hypotension (relative risk=1.036/min; P=0.0125). Death during the first year after surgery is primarily associated with the natural history of preexisting conditions. However, cumulative deep hypnotic time and intraoperative hypotension were also significant, independent predictors of increased mortality. These associations suggest that intraoperative anesthetic management may affect outcomes over longer time periods than previously appreciated.

Developmental Disability in the Young and Postoperative Cognitive Dysfunction in the Elderly After Anesthesia and Surgery: Do Data Justify Changing Clinical Practice?

“…Corroborating earlier work, 87 this study also found a substantial relationship between POCD and death within 1 year of surgery. 88,89 Independent risk factors for sustained POCD included greater age, less education, POCD at hospital discharge, and a history of stroke without residual damage.…”

“…118 In a separate group of rats, they found that the same nitrous oxide exposure profoundly, but transiently, reduced the activity of cortical methionine synthase-an enzyme that is implicated in dementia and may be related to accumulation of homocysteine (a cytotoxic amino acid normally remethylated to methionine, an essential amino acid, by methionine synthase). 118 Evidence from Monk's 2005 study indicated that cumulative deep hypnotic time is associated with more POCD, 87 with a substantial relationship between POCD and death within 1 year of surgery. 88,89 In distinction, a study by Schubert's group looked at lighter anesthesia (bispectral index [BIS] 50) versus deeper anesthesia (BIS 39) and found that deeper levels of anesthesia were associated with better cognitive function 4-6 weeks postoperatively.…”

Does heart rate variability predict hypotension and bradycardia after induction of general anaesthesia in high risk cardiovascular patients?*

“…These results were confirmed in another group of patients assigned by baseline TP. It has been demonstrated that hypotension during anaesthesia may worsen patient outcome [23][24][25]. More than 50 years ago, Kleinerman et al [23] showed that the degree of hypotension correlated with the decrease of cerebral blood flow.…”

“…A MAP decrease of 26% resulted in a decrease of cerebral blood flow of 12%, whereas a MAP decrease of 50% correlated with a drop of cerebral blood flow of 20%. Monk et al identified three independent risk factors for 1-year mortality following surgery in 1064 patients, one of which was intra-operative hypotension [24]. A third investigation found that the incidence of postoperative delirium was higher (9% vs 4%) in patients with MAP between 45 and 55 mmHg compared with patients with MAP between 55 and 70 mmHg [25].…”

Neuraxial anesthesia improves long-term survival after total joint replacement: a retrospective nationwide population-based study in Taiwan

“…This finding is consistent with the results reported by Monk et al, who found that the mortality rate during the first postoperative year might be affected by anesthetic management. 22 In an observational study of 1,064 patients, they found that the Charlson comorbidity index score, cumulative deep hypnotic time, and intraoperative hypotension (systolic blood pressure \ 80 mmHg) were significant independent predictors of the one-year mortality rate. Brown et al also found that the hypnotic depth might be associated with the one-year mortality rate in elderly patients during repair of hip fractures under spinal anesthesia.…”