Predictors of cognitive dysfunction after major noncardiac surgery.

Background: The authors designed a prospective longitudinal study to investigate the hypothesis that advancing age is a risk factor for postoperative cognitive dysfunction (POCD) after major noncardiac surgery and the impact of POCD on mortality in the first year after surgery.

Methods: One thousand sixty-four patients aged 18 yr or older completed neuropsychological tests before surgery, at hospital discharge, and 3 months after surgery. Patients were categorized as young (18-39 yr), middle-aged (40-59 yr), or elderly (60 yr or older).

An integrated coronary circulation teaching model.

Objectives: We present in this paper a model of the coronary circulation. This model is integrated with a model of the systemic circulation, and contains models for oxygen supply and demand.

Methods: Three compartments are created: one for the right ventricle, one for the epicardial segment of the left ventricle and one for the endo-cardial segment of the left ventricle.

Learning about new anesthetics using a model driven, full human simulator.

Objective: New pharmacological agents are introduced into medical practice at an ever-increasing pace. Teaching how to use new medications in the clinical setting presents educational challenges and puts patients at risk.

Methods: Patients and clinical settings in which remifentanil might provide clinical advantages over existing anesthetics were identified.

Safety in anesthesia.

The specialty of anesthesiology has made extraordinary advances in anesthesia safety. Yet, anesthetic mortality and morbidity continue to be far from tolerable. Efforts to enhance safety in anesthesia must include adherence to explicit and implicit safety standards, must make use of equipment that offers modern safety features, must seek to detect and correct developing safety threats as early as possible and must have a structured system to analyze problems and to institute remedies to prevent their recurrence.

How does human error affect safety in anesthesia?

Anesthesia morbidity and mortality, while acceptable, are not zero. Most mishaps have a multifactorial cause in which human error plays a significant part. Good design of anesthesia machines, ventilators, and monitors can prevent some, but not all, human error.

Influence of pulse oximetry and capnography on time to diagnosis of critical incidents in anesthesia: a pilot study using a full-scale patient simulator.

Objective: Many studies (outcome, epidemiological) have tested the hypothesis that pulse oximetry and capnography affect the outcome of anesthetic care. Uncontrollable variables in clinical studies make it difficult to generate statistically conclusive data. In the present study, we eliminated the variability among patients and operative procedures by using a full-scale patient simulator.

TWITCHER: a device to stimulate thumb twitch response to ulnar nerve stimulation.

Objective: To design and fabricate a device to simulate evoked thumb adduction in response to ulnar nerve stimulation.

Methods: We implemented a computer-controlled, motorized thumb (TWITCHER) that responds to ulnar nerve stimulation by an unmodified peripheral nerve stimulator. Clinically realistic response patterns are generated for both depolarizing and non-depolarizing muscle relaxants and three modes of stimulation (single twitch, train-of-four, tetanus).

[Monitoring in anesthesiologic practice].

Monitoring has made great strides in the last half century. It enables us to titrate drugs to the desired effect, warns us of impending danger, and helps with the diagnosis of problems confronting our patients. Beyond that it has enormously increased our understanding of anesthetic pathophysiology.

Long-term postoperative cognitive dysfunction in the elderly ISPOCD1 study. ISPOCD investigators. International Study of Post-Operative Cognitive Dysfunction.

Background: Long-term postoperative cognitive dysfunction may occur in the elderly. Age may be a risk factor and hypoxaemia and arterial hypotension causative factors. We investigated these hypotheses in an international multicentre study.

Computerized pre-anesthetic evaluation results in additional abstracted comorbidity diagnoses.

Objective: To study the impact of information from a physician-entry computerized preanesthetic evaluation system on the coding of International Classification of Diseases (ICD-9-CM) diagnoses and on hospital reimbursement due to alterations in diagnosis-related group (DRG) codes.

Methods: Nonrandomized, unblinded trial conducted at a 570-bed university tertiary care hospital. First without and then with reference to information contained on computer-based preanesthetic evaluation reports, medical charts were coded by the study institution's usual professional codes for ICD-9-CM discharge diagnoses and DRG assignment.

The efficiency of preoperative evaluation: a comparison of computerized and paper recording systems.

Objective: We designed and implemented a preoperative evaluation record system with seven networked computers for use by physicians and other medical staff. This study compared the efficiency of the new computerized system with that of the paper system.

Methods: We reviewed data from preoperative evaluations completed from November 1990 through December 1992.

Acceptable ranges for vital signs during general anesthesia.

Objective: Define the ranges for normal vital signs during general anesthesia.

Methods: We studied 50 patients undergoing general anesthesia. We asked residents to state desirable ranges for each patient's systolic and diastolic blood pressure (BP), heart rate (HR), SpO2, and PETCO2 during induction, intubation, maintenance, and emergence from anesthesia.

Perioperative monitoring with pulse oximetry and late postoperative cognitive dysfunction.

In a randomized, blinded clinical study, we have used objective and subjective measures to determine if perioperative monitoring with pulse oximetry--by virtue of its potential to lessen hypoxaemia--would decrease late postoperative cognitive dysfunction. We investigated 736 adult patients undergoing elective procedures (other than cardiac, neurosurgical or for cancer) under regional or general anaesthesia, allocated randomly to undergo (group I) or not to undergo (group II) pulse oximetry monitoring in the operating theatre and recovery room. Cognitive function was evaluated using the Wechsler memory scale (WMS) and continuous reaction time (RT) test the day before surgery, and on the 7th day after operation or at discharge if that occurred before postoperative day 7.

[Anesthesia simulators and training devices].

Simulators and training devices are used extensively by educators in 'high-tech' occupations, especially those requiring an understanding of complex systems and co-ordinated psychomotor skills. Because of advances in computer technology, anaesthetised patients can now be realistically simulated. This paper describes several training devices and a simulator currently being employed in the training of anaesthesia personnel at the University of Florida.

Technology and the growth of anaesthesiology as a specialty.

Clinical monitoring techniques have affected patients, influenced other specialties; and changed the specialty of anaesthesia. Patients now fare better, the progress of surgery has been facilitated, and anaesthesiology itself has felt the impact of these developments. Technological advance stimulates our understanding of physiological processes, which is a foundation for progress yet to come.