Design considerations for a personalized wheelchair navigation system.

Individuals with mobility impairments such as wheelchair users are often at a disadvantage when traveling to a new place, as their mobility can be easily affected by environmental barriers, and as such, even short trips can be difficult and perhaps impossible. We envision a personalized wheelchair navigation system based on a PDA equipped with wireless Internet access and GPS that can provide adaptive navigation support to wheelchair users in any geographic environment. Requirements, architectures and components of such a system are described in this paper.

Remifentanil compared with alfentanil for ambulatory surgery using total intravenous anesthesia. The Remifentanil/Alfentanil Outpatient TIVA Group.

The purpose of this study was to test the hypothesis that using a 1:4 ratio of remifentanil to alfentanil, a remifentanil infusion would provide better suppression of intraoperative responses and comparable recovery profiles after ambulatory laparoscopic surgery than an alfentanil infusion, as part of total intravenous anesthesia. Two hundred ASA physical status I, II, or III adult patients participated in this multicenter, double-blind, parallel group study. Patients were randomly assigned 2:1 to either the remifentanil-propofol or alfentanil-propofol regimens.

Ondansetron prevents postoperative nausea and vomiting in women outpatients.

Three doses of intravenous (i.v.) ondansetron, 1 mg, 4 mg, and 8 mg, were compared to placebo for their antiemetic effect and safety.

Cardiovascular stability with rapid intravenous infusion of ondansetron.

The acute cardiovascular effects of rapid iv administration of the antiemetic ondansetron, a selective serotonin (5-HT3) receptor antagonist were determined in a randomized, blinded, placebo-controlled study. Measurements of heart rate, blood pressure, oxygen saturation and respiratory rate were made preoperatively over a five-minute period which followed a two-minute infusion of the medication. Intraoperative and postoperative data were not collected.

Unregulated self-medication in an ambulatory surgery population.

The objective of this study was to determine whether unregulated self-medication in an ambulatory surgery population was a significant problem in terms of the incidence and nature of drugs detected. We asked 67 consecutive patients who presented for elective ambulatory surgery at a university medical center to volunteer for serum and urine testing with the assurance of confidentiality. All patients denied nonprescription drug use.

Comparison of desflurane with propofol in outpatients undergoing peripheral orthopedic surgery.

This study was undertaken to compare desflurane with propofol anesthesia in outpatients undergoing peripheral orthopedic surgery. Data were combined from two institutions participating in a multicenter study. Ninety-one patients, ASA physical status I or II, were each randomly assigned to one of four groups.

Arthroscopic surgery of the knee under local anesthesia.

This report delineates the efficacy of local anesthesia in the performance of arthroscopic surgery of the knee. A retrospective review of 500 cases revealed that only three required administration of general anesthesia to successfully complete the procedure. A prospective study comparing fentanyl, midazolam, and fentanyl/midazolam combinations as intravenous supplements was performed.

Effect of alterations in frequency, inspiratory time, and airway pressure on gas exchange during high frequency jet ventilation in dogs with normal lungs.

High frequency jet ventilation (HFJV) is becoming increasingly useful for providing respiratory support in patients with normal lungs during operative procedures, and also has been advocated as a technique for ventilating patients during cardiopulmonary resuscitation. We studied the effect of frequency, percent inspiratory time (I/E ratio), peak airway pressure, and airway pressure difference (peak-PEEP) during HFJV as operational variables on the efficacy of gas exchange in dogs with normal lungs. We observed that at a constant peak airway pressure and percent inspiratory time, PaCO2 generally increases as frequency rises above 100/min.

A departmental policy addressing chemical substance abuse.

Substance abuse is a major socioeconomic problem. However, the ready availability of potent narcotic and sedative drugs probably constitutes a unique risk for anesthesiologists. Until recently, few anesthesia departments were prepared to recognize or safely manage afflicted colleagues.

Comparison of high-frequency jet ventilation with conventional mechanical ventilation in saline-lavaged rabbits.

A surfactant-depletion lung-injury model was produced in 37 New Zealand white rabbits by saline lavage. During the next 2 to 3 h, rabbits were ventilated with conventional mechanical ventilation (CMV, group 1), high-frequency jet ventilation (HFJV, group 2), or CMV for 1 h followed by HFJV for 2 h (CMV/HFJV, group 3). Survival until planned termination of the protocol was 56%, 77%, and 63% in groups 1, 2 and 3, respectively.

Airway movement in dogs during high-frequency jet ventilation.

Cine tantalum bronchograms were recorded from 7 pentobarbital-anesthetized dogs during spontaneous ventilation (SV), high-frequency jet ventilation (HFJV) at 3 frequencies, and intermittent positive-pressure ventilation (IPPV) at 3 combinations of tidal volume (VT) and rate. During SV and the 3 IPPV conditions, the percent inspiratory increase in the diameter of airways greater than 3 mm was the same as in airways less than 3 mm. With HFJV, the percent increase in the diameter of airways greater than 3 mm was twice that of smaller airways.

Fentanyl sequestration in lungs during cardiopulmonary bypass.

Serum fentanyl concentrations were measured before, during, and after cardiopulmonary bypass and correlated with changes in total protein, albumin, hematocrit, pH, and PCO2 in five patients undergoing cardiac surgery. Serum fentanyl concentrations, total protein, albumin, and hematocrit declined with initiation of bypass but remained unchanged thereafter. PCO2 and pH did not change.

Hemodynamic effects of high-frequency jet ventilation.

The hemodynamic effects of high-frequency jet ventilation (HFJV) and conventional ventilation were compared in normovolemic and functionally hypovolemic dogs. In normovolemic animals, no differences in hemodynamic function were found among spontaneous ventilation, conventional ventilation, and HFJV. When venous return was impaired by 15 cm H2O PEEP, cardiac index and stroke index were 25% higher with HFJV than with conventional ventilation (P less than 0.

Cardiovascular effects of protamine sulfate in man.

The effect of protamine sulfate on several cardiovascular and biochemical variables was studied in man under clinical conditions. This study was performed to quantitate these effects in 15 adult patients who had undergone cardiopulmonary bypass for coronary artery bypass grafting. Protamine was administered in typical clinical doses (3 mg/kg) at typical clinical rates (total dose infused over 5 minutes).

Peripheral vascular response to potassium administration during cardiopulmonary bypass.

Potassium (K+) is often administered to patients during cardiopulmonary bypass (CPB). The effects of rapid K+ administration during CPB were studied in 30 adult patients. Each patient received one bolus dose (2, 4, 8, 12, or 16 mEq) of potassium chloride (KCl) (2 mEq/ml) during CPB.