Marina Krol

Predictors of hypotension after induction of general anesthesia.

Hypotension after induction of general anesthesia is a common event. In the current investigation, we sought to identify the predictors of clinically significant hypotension after the induction of general anesthesia. Computerized anesthesia records of 4096 patients undergoing general anesthesia were queried for arterial blood pressure (BP), demographic information, preoperative drug history, and anesthetic induction regimen. The median BP was determined preinduction and for 0–5 and 5–10 min postinduction of anesthesia. Hypotension was defined as either: mean arterial blood pressure (MAP) decrease of >40% and MAP <70 mm Hg or MAP <60 mm Hg. Overall, 9% of patients experienced severe hypotension 0–10 min postinduction of general anesthesia. Hypotension was more prevalent in the second half of the 0–10 min interval after anesthetic induction (P < 0.001). In 2406 patients with retrievable outcome data, prolonged postoperative stay and/or death was more common in patients with versus those without postinduction hypotension (13.3% and 8.6%, respectively, multivariate P < 0.02). Statistically significant multivariate predictors of hypotension 0–10 min after anesthetic induction included: ASA III–V, baseline MAP <70 mm Hg, age ≥50 yr, the use of propofol for induction of anesthesia, and increasing induction dosage of fentanyl. Smaller doses of propofol, etomidate, and thiopental were not associated with less hypotension. To avoid severe hypotension, alternatives to propofol anesthetic induction (e.g., etomidate) should be considered in patients older than 50 yr of age with ASA physical status ≥3. We conclude that it is advisable to avoid propofol induction in patients who present with baseline MAP <70 mm Hg.

Beneficial effects from β-adrenergic blockade in elderly patients undergoing noncardiac surgery

BackgroundPerioperative β-blockade has been shown to improve long-term cardiac outcome in noncardiac surgical patients. A possible mechanism for the reduced risk of perioperative myocardial infarction is the attenuation of the excitotoxic effects of catecholamine surges by β-blockade. It was hypothe

Intraoperative hemodynamic predictors of mortality, stroke, and myocardial infarction after coronary artery bypass surgery.

UNLABELLED Evidence that intraoperative hemodynamic abnormalities influence outcome is limited. The purpose of this study was to determine whether intraoperative hemodynamic abnormalities were associated with mortality, stroke, or perioperative myocardial infarction (PMI) in a large cohort of patients undergoing coronary artery bypass grafting. Risk factors and outcomes were queried from a state-mandated cardiac surgery reporting system at two hospitals in New York, NY. Intraoperative hemodynamic abnormalities were derived from computerized anesthesia records by assessing the duration of exposure to moderate or severe extremes of hemodynamic variables. Multivariate logistic regression identified independent predictors of perioperative mortality, stroke, and PMI. Among 2149 patients, there were 50 mortalities, 51 strokes, and 85 PMIs. In the precardiopulmonary bypass (pre-CPB) period, pulmonary hypertension was a predictor of mortality (odds ratio [OR] 2.1, P = 0.029), and bradycardia and tachycardia were predictors of PMI (OR 2.9, P = 0.007 and OR 2.0, P = 0.028, respectively). During CPB, hypotension was a predictor of mortality (OR 1.3, P = 0.025). Post-CPB, tachycardia was a predictor of mortality (OR 3.1, P = 0.001), diastolic arterial hypertension was a predictor of stroke (OR 5.4, P = 0.012), and pulmonary hypertension was a predictor of PMI (OR 7.0, P < 0.001). Increased pulmonary arterial diastolic pressure post-CPB was a predictor of mortality (OR 1.2, P = 0.004), stroke (OR 3.9, P = 0.002), and PMI (OR 2.2, P = 0.001). Rapid intraoperative variations in blood pressure and heart rate were not independent predictors of these outcomes. These findings demonstrate the prognostic significance of intraoperative hemodynamic abnormalities, including data from pulmonary artery catheterization, to adverse postoperative outcomes. It is not known whether interventions to control these variables would improve outcome. IMPLICATIONS Intraoperative hemodynamic abnormalities, including pulmonary hypertension, hypotension during cardiopulmonary bypass, and postcardiopulmonary bypass pulmonary diastolic hypertension, were independently associated with mortality, stroke, and perioperative myocardial infarction over and above the effects of other preoperative risk factors.

Intraoperative tachycardia and hypertension are independently associated with adverse outcome in noncardiac surgery of long duration.

Relatively little is known about the influence of intraoperative hemodynamic variables on surgical outcomes. We drew subjects (n = 797) from a study of patients undergoing major noncardiac surgery. The physiological component of the POSSUM (Physiological and Operative Se- verity Score for the enUmeration of Mortality) operative risk stratification index was determined, and intraoperative measurements of heart rate (HR), mean arterial blood pressure, and systolic arterial blood pressure (SAP) were retrieved from computerized anesthesia records. For every 5-min epoch during the surgery, HR, mean arterial blood pressure, and SAP were each classified as low, normal, or high. Negative surgical outcome (NSO) was defined as a hospital stay of >10 days with a morbid condition or death during the hospital stay. Statistical analyses included Mantel-Haenszel tests and multiple logistic regression. There was no significant association between hemodynamic variables and NSO with short operations. In 388 patients with operations longer than the median time of 220 min, NSO occurred in 15.6%. Controlling for POSSUM score and operation time beyond 220 min, both high HR (odds ratio, 2.704;P = 0.01) and high SAP (odds ratio, 2.095;P = 0.009) were associated with NSO in longer operations. Thus, intraoperative tachycardia and hypertension were associated independently with adverse outcomes after major noncardiac surgery of long duration, over and above the risk imparted by underlying medical conditions.

Arterial blood pressure and heart rate discrepancies between handwritten and computerized anesthesia records.

Previous publications suggest that handwritten anesthesia records are less accurate when compared with computer-generated records, but these studies were limited by small sample size, unblinded study design, and unpaired statistical comparisons. Eighty-one pairs of handwritten and computer-generated neurosurgical anesthesia records were retrospectively compared by using a matched sample design. Systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and heart rate (HR) data for each 5-min interval were transcribed from handwritten records. In computerized records, the median of up to 20 values was calculated for SAP, DAP, and HR for each consecutive 5-min epoch. The peak, trough, standard deviation, median, and absolute value of the fractional rate of change between adjacent 5-min epochs were calculated for each case. Pairwise comparisons were performed by using Wilcoxon tests. For SAP, DAP, and HR, the handwritten record peak, standard deviation, and fractional rate of change were less than, and the trough and median were larger than, those in corresponding computer records (all with P < 0.05, except DAP median and HR peak). Considering together all the recorded measurements from all cases, extreme values were recorded more frequently in computerized records than in the handwritten records. Implications The discrepancies between handwritten and computerized anesthesia records suggest that some of the data in handwritten records are inaccurate. The potential for inaccuracy should be considered when handwritten records are used as source material for research, quality assurance, and medicolegal purposes.

The effect of an interactive visual reminder in an anesthesia information management system on timeliness of prophylactic antibiotic administration.

BACKGROUND:To reduce the incidence of surgical site infection, preoperative antibiotics should be administered within 60 min before surgical incision. The purpose of this study was to determine whether adding a visual interactive electronic reminder with a message related to antibiotic administration to our anesthesia information management system would increase compliance with prophylactic antibiotic guidelines. METHODS:We retrospectively studied electronic anesthesia records of ambulatory and day-of-surgery admission surgical cases in which one of our usual prophylactic antibiotics was administered from June 2004 through December 2005, an interval that includes cases both before and after the February 2005 implementation of the new reminder. Compliance was defined as documented antibiotic administration within 60 min before the surgical procedure starting time. Noncompliant cases were divided into those in which dosing was too early or too late. RESULTS:Compliance for 4987 cases before and 9478 cases after the reminder was implemented increased from 82.4% to 89.1% (P < 0.01). This increase was found both for attending anesthesiologists assisted by a resident or nurse anesthetist (82.9% before vs 89.1% after, P < 0.01) and for attending anesthesiologists working alone (80.1% before vs 89.3% after, P < 0.01). The improvement in compliance was associated with a decrease in the incidence of antibiotics administered too late (i.e., after surgical incision) (15.2% before vs 8.1% after, P < 0.01), but with no significant change in the incidence of antibiotics administered too early (i.e., more than 60 min before skin incision) (2.4% before vs 2.8% after, P = 0.07). CONCLUSIONS:The implementation of a visual interactive electronic reminder regarding administration of preoperative antibiotics in an anesthesia information management system was associated with a sustained increase in compliance with surgical prophylactic antibiotic administration timing guidelines.

The Anesthetic Considerations in Patients with Ventricular Assist Devices Presenting for Noncardiac Surgery: A Review of Eight Cases

IMPLICATIONS The number of patients supported by ventricular assist devices (VADs) that present for noncardiac surgery is increasing in our institution. Our recent experience with eight such patients is reported, along with a review of the most commonly implanted VADs and the anesthetic implications and considerations for VAD-supported patients undergoing noncardiac surgery.

Predictive Model for Postoperative Delirium in Cardiac Surgical Patients

Delirium is a common complication following cardiac surgery, and the predictors of delirium remain unclear. The authors performed a prospective observational analysis to develop a predictive model for postoperative delirium using demographic and procedural parameters. A total of 112 adult postoperative cardiac surgical patients were evaluated twice daily for delirium using the Richmond Agitation-Sedation Scale (RASS) and Confusion Assessment Model for the ICU (CAM-ICU). The incidence of delirium was 34% (n = 38). Increased age (odds ratio [OR] = 2.5; 95% confidence interval [CI] = 1.6-3.9; P < .0001, per 10 years) and increased duration of surgery (OR = 1.3; 95% CI = 1.1-1.5; P = .0002, per 30 minutes) were independently associated with postoperative delirium. Gender, BMI, diabetes mellitus, preoperative ejection fraction, surgery type, length of cardiopulmonary bypass, intraoperative blood component administration, Acute Physiology and Chronic Health Evaluation II score, Sequential Organ Failure Assessment score, and Charlson Comorbidity Index, were not independently associated with postoperative delirium.

Development of a module for point-of-care charge capture and submission using an anesthesia information management system.

Background:The use of electronic charge vouchers in anesthesia practice is limited, and the effects on practice management are unreported. The authors hypothesized that the new billing technology would improve the effectiveness of the billing interface and enhance financial practice management measures. Methods:A custom application was created to extract billing elements from the anesthesia information management system. The application incorporates business rules to determine whether individual cases have all required elements for a complete and compliant bill. The metrics of charge lag and days in accounts receivable were assessed before and after the implementation of the electronic charge voucher system. Results:The average charge lag decreased by 7.3 days after full implementation. The total days in accounts receivable, controlling for fee schedule changes and credit balances, decreased by 10.1 days after implementation, representing a one-time revenue gain equivalent to 3.0% of total annual receipts. There are additional ongoing cost savings related to reduction of personnel and expenses related to paper charge voucher handling. Conclusions:Anesthesia information management systems yield financial and operational benefits by speeding up the revenue cycle and by reducing direct costs and compliance risks related to the billing and collection processes. The observed reductions in charge lag and days in accounts receivable may be of benefit in calculating the return on investment that is attributable to the adoption of anesthesia information management systems and electronic charge transmission.

A Mission-Based Productivity Compensation Model for an Academic Anesthesiology Department

INTRODUCTION:We replaced a nearly fixed-salary academic physician compensation model with a mission-based productivity model with the goal of improving attending anesthesiologist productivity. METHODS:The base salary system was stratified according to rank and clinical experience. The supplemental pay structure was linked to electronic patient records and a scheduling database to award points for clinical activity; educational, research, and administrative points systems were constructed in parallel. We analyzed monthly American Society of Anesthesiologist (ASA) unit data for operating room activity and physician compensation from 2000 through mid-2007, excluding the 1-yr implementation period (July 2004–June 2005) for the new model. RESULTS:Comparing 2005–2006 with 2000–2004, quarterly ASA units increased by 14% (P = 0.0001) and quarterly ASA units per full-time equivalent increased by 31% (P < 0.0001), while quarterly ASA units per anesthetizing location decreased by 10% (P = 0.046). Compared with a baseline year (2001), Instructor and Assistant Professor faculty compensation increased more than Associate Professor and Professor faculty (P < 0.001) in both pre- and postimplementation periods. There were larger compensation increases for the postimplementation period compared with preimplementation across faculty rank groupings (P < 0.0001). Academic and educational output was stable. DISCUSSION:Implementing a productivity-based faculty compensation model in an academic department was associated with increased mean supplemental pay with relatively fewer faculty. ASA units per month and ASA units per operating room full-time equivalent increased, and these metrics are the most likely drivers of the increased compensation. This occurred despite a slight decrease in clinical productivity as measured by ASA units per anesthetizing location. Academic and educational output was stable.