In a prospective study of 6301 surgical patients in a university hospital, we examined the strength of association between ASA physical status classification and perioperative risk factors, and postoperative outcome, using both univariate analysis and calculation of the odds ratio of the risk of developing a postoperative complication by means of a logistic regression model. Univariate analysis showed a significant correlation (P

ASA classification and perioperative variables as predictors of postoperative outcome.

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, preop

Anesthetic management and one-year mortality after noncardiac surgery.

The recommended treatment of distal gastric cancer consists of a radical resection of the distal 4/5 of the stomach with a free margin of 5 to 6 cm.1–3 The extent of the associated lymph node dissection is still debated. Japanese authors suggest an extended dissection with the routine involvement of D1 and D2 lymph nodes, while an even wider (D3 and D4) dissection is advocated in cases of suspected invasion of more distant lymph nodes.4–8 Western authors often prefer a limited dissection (D1) because of the higher operative mortality and morbidity rates associated with extended lymphadenectomy (D2),9–13 even when distal pancreatectomy is avoided, as well as the lack of a significantly improved long-term survival data.14–18

In the past decade, laparoscopic techniques have gained wide clinical acceptance in surgical practice. This approach offers important advantages when compared with open surgery: reduced intraoperative blood loss, reduced postoperative pain and accelerated recovery, earlier return to normal bowel function with earlier resumption of oral intake, early discharge from hospital, and lower financial costs.19–22

The same advantages have been reported after laparoscopic subtotal or total gastrectomy for benign tumors as well as early gastric cancers.23–31 However, laparoscopically assisted subtotal gastrectomy for distal gastric cancer can only be justified and widely accepted as a safer alternative to open surgery if equal long-term results are obtained. This would suggest an equivalent radical oncologic resection.

The purpose of our study was to compare early and 5-year results of subtotal gastrectomy performed for distal gastric cancer using both a laparoscopic and an open approach, therefore defining the role of laparoscopic surgery in the treatment of this disease.

Laparoscopic versus open subtotal gastrectomy for distal gastric cancer: five-year results of a randomized prospective trial

Background: Although deviations in intraoperative blood pressure are assumed to be associated with postoperative mortality, critical blood pressure thresholds remain undefined. Therefore, the authors estimated the intraoperative thresholds of systolic blood pressure (SBP), mean blood pressure (MAP), and diastolic blood pressure (DBP) associated with increased risk-adjusted 30-day mortality. 

Methods: This retrospective cohort study combined intraoperative blood pressure data from six Veterans Affairs medical centers with 30-day outcomes to determine the risk-adjusted associations between intraoperative blood pressure and 30-day mortality. Deviations in blood pressure were assessed using three methods: (1) population thresholds (individual patient sum of area under threshold [AUT] or area over threshold 2 SDs from the mean of the population intraoperative blood pressure values), (2). absolute thresholds, and (3) percent change from baseline blood pressure. 

Results: Thirty-day mortality was associated with (1) population threshold: systolic AUT (odds ratio, 3.3; 95% CI, 2.2 to 4.8), mean AUT (2.8; 1.9 to 4.3), and diastolic AUT (2.4; 1.6 to 3.8). Approximate conversions of AUT into its separate components of pressure and time were SBP < 67 mmHg for more than 8.2 min, MAP < 49 mmHg for more than 3.9 min, DBP < 33 mmHg for more than 4.4 min. (2) Absolute threshold: SBP < 70 mmHg for more than or equal to 5 min (odds ratio, 2.9; 95% CI, 1.7 to 4.9), MAP < 49 mmHg for more than or equal to 5 min (2.4; 1.3 to 4.6), and DBP < 30 mmHg for more than or equal to 5 min (3.2; 1.8 to 5.5). (3) Percent change: MAP decreases to more than 50% from baseline for more than or equal to 5 min (2.7; 1.5 to 5.0). Intraoperative hypertension was not associated with 30-day mortality with any of these techniques. 

Conclusion: Intraoperative hypotension, but not hypertension, is associated with increased 30-day operative mortality.

Association between Intraoperative Hypotension and Hypertension and 30-day Postoperative Mortality in Noncardiac Surgery

Background Previous studies, which relied on hypothetical cases and chart reviews, have questioned the inter-rater reliability of the ASA physical status (ASA-PS) scale. We therefore conducted a retrospective cohort study to evaluate its inter-rater reliability and validity in clinical practice. Methods The cohort included all adult patients (≥18 yr) who underwent elective non-cardiac surgery at a quaternary-care teaching institution in Toronto, Ontario, Canada, from March 2010 to December 2011. We assessed inter-rater reliability by comparing ASA-PS scores assigned at the preoperative assessment clinic vs the operating theatre. We also assessed the validity of the ASA-PS scale by measuring its association with patients' preoperative characteristics and postoperative outcomes. Results The cohort included 10 864 patients, of whom 5.5% were classified as ASA I, 42.0% as ASA II, 46.7% as ASA III, and 5.8% as ASA IV. The ASA-PS score had moderate inter-rater reliability (κ 0.61), with 67.0% of patients (n=7279) being assigned to the same ASA-PS class in the clinic and operating theatre, and 98.6% (n=10 712) of paired assessments being within one class of each other. The ASA-PS scale was correlated with patients' age (Spearman's ρ, 0.23), Charlson comorbidity index (ρ=0.24), revised cardiac risk index (ρ=0.40), and hospital length of stay (ρ=0.16). It had moderate ability to predict in-hospital mortality (receiver-operating characteristic curve area 0.69) and cardiac complications (receiver-operating characteristic curve area 0.70). Conclusions Consistent with its inherent subjectivity, the ASA-PS scale has moderate inter-rater reliability in clinical practice. It also demonstrates validity as a marker of patients' preoperative health status.

Robert J. VanHOUTEN

Papers

A statistical analysis of the relationship of physical status to postoperative mortality in 68,388 cases.