Information gain in patients using a multimedia website with tailored information on anaesthesia.

BACKGROUND: The preoperative visit is an appropriate time to educate the patient on anaesthesia. The aim of this study was to determine if a website, as an information source for anaesthesia before the visit to the preoperative assessment clinic (PAC), increases patients' knowledge on anaesthesia. METHODS: A multimedia website was developed containing specific information about anaesthesia relevant to the patient. A questionnaire was developed to measure knowledge gain. Patients were divided into three groups: (i) those who read the existing brochure; (ii) those who looked at the new website; and (iii) a cluster of non-brochure and non-website users: those who did not read the brochure or website but had completed the questionnaire. An anaesthesiologist also informed all three groups during the preoperative visit at the PAC. RESULTS: Patients visiting the website had a higher educational level than others. A significant increase in knowledge was observed after using the website information compared with the other two groups (P<0.001). The group with higher education levels had higher knowledge gains, and the website independently contributed to the knowledge gain. CONCLUSIONS: A patient-tailored multimedia website is an effective way to support the information provided by the anaesthesiologist in order to inform patients about their upcoming anaesthetic procedure. The use of such a website gives a significant increase in knowledge compared with only spoken information, or spoken information combined with a brochure.

Comparing the organisational structure of the preoperative assessment clinic at eight university hospitals.

The preoperative assessment clinic (PAC) has been implemented in most major hospitals. However, there is no uniformity in the way PACs are organised. We compared the organisational structure of the PACs from all eight university hospitals in The Netherlands, looking at the following variables: number of patients visiting the PAC, staffing of the PAC, opening hours, scheduling, and additional preoperative diagnostic testing. The number of patients seen yearly varies from 7.000 to 13.500. In all clinics, the preoperative assessment was performed by anaesthetists and residents. In five PACs, preoperative assessment was also performed by physician assistants or nurse practitioners. Opening hours varied. Consultations are by appointment, 'walk-in', or a combination of these two. In four clinics additional testing is performed at the PAC itself. This study shows that the organisational structure of the PAC at similar university hospitals varies greatly; this can have important implications when designing a benchmarking process.

Clinical evaluation of Duraflo II heparin treated extracorporeal circulation circuits (2nd version). The European Working Group on heparin coated extracorporeal circulation circuits.

OBJECTIVES: To evaluate whether the application of heparin treated circuits for elective coronary artery surgery improves postoperative recovery, a European multicenter randomised clinical trial was carried out. METHODS: In 11 European heart centers, 805 low-risk patients underwent cardiopulmonary bypass (CPB) with either an untreated circuit (n = 407) or an identical but heparin treated circuit (n = 398, Duraflo II). RESULTS: Significant differences were found among participating centers with respect to patient characteristics, blood handling procedures and postoperative care. The use of heparin treated circuits revealed no overall changes in blood loss, blood use, time on ventilator, occurrence of adverse events, morbidity, mortality, and intensive care stay. These results did not change after adjustment for centers and (other) prognostic factors as analysed with logistic regression. In both groups no clinical or technical (patient or device related) side effects were reported. Because female gender and aortic cross clamp time appeared as prognostic factors in the logistic regression analysis, a subgroup analysis with these variables was performed. In a subpopulation of females (n = 99), those receiving heparin treated circuits needed less blood products, had a lower incidence of rhythm disturbances and were extubated earlier than controls. In another subgroup of patients with aortic cross clamp time exceeding 60 min (n = 197), the amount of patients requiring prolonged intensive care treatment (> 24 h) was significantly lower when they received heparin treated circuits versus controls. CONCLUSION: These findings suggest that improved recovery can be expected with heparin treated circuits in specific higher risk patient populations (e.g. females) and when prolonged aortic cross clamp time is anticipated. Further investigations are recommended to analyses the clinical benefit of heparin treated circuits in studies with patients in different well defined risk categories and under better standardised circumstances.

The effects of propofol compared to high-dose fentanyl anesthesia on rheologic parameters in coronary artery surgery.

Propofol has previously been found to decrease hematocrit values. Because hematocrit is an important determinant of blood viscosity, lower hematocrits may cause a decrease in blood viscosity, improving blood flow and oxygen delivery. This phenomenon may be beneficial in certain intraoperative situations. To study the influence of two anesthetic techniques on a variety of rheologic parameters, 32 patients scheduled for coronary artery bypass grafting (CABG) were divided into two groups. Group I (n = 18) was induced with high-dose fentanyl anesthesia (100 micrograms/kg), and group II (n = 16) with a combination of propofol and fentanyl anesthesia (1 to 1.5 mg/kg and 35 to 50 micrograms/kg, respectively). Maintenance anesthesia continued with infusions of the same drugs. Blood and plasma viscosity, hematocrit, erythrocyte aggregation factor, and erythrocyte deformability were measured preoperatively, intraoperatively, and up to 48 hours postoperatively. Whole blood viscosity was corrected to a standard hematocrit of 0.45. The two groups were comparable with respect to age, bypass duration, blood loss, urine output, transfusions, and fluid management. Erythrocyte deformability did not decrease during or after cardiopulmonary bypass (CPB). In both groups, hematocrit and blood and plasma were decreased significantly during and after CPB (P < 0.01) and returned to baseline levels 48 hours after surgery. After induction and before CPB, blood viscosity was only decreased in group II. However, the corrected blood viscosity was significantly elevated at all shear rates in group II compared to group I at 24 and 48 hours postoperatively (P < 0.01). In group II at these sampling times, this parameter was also significantly elevated compared to preoperative values.(ABSTRACT TRUNCATED AT 250 WORDS)

Systolic and diastolic pressure-volume relationships during cardiac surgery.

Seven patients undergoing elective coronary artery bypass surgery were studied to assess left ventricular (LV) performance by pressure-volume loops. LV pressure was measured by micromanometry and instantaneous LV volume by a conductance catheter. Continuous pressure-volume relationships were determined during preload reduction before and after cardiopulmonary bypass (CPB). End-systolic elastance (Ees), as the slope of the end-systolic pressure-volume relationship (ESPVR), and diastolic elastance (Ed) were calculated from these interventions. Changes in position of the Ees were assessed at V75, the value of LV end-systolic volume at 75 mm Hg of LV pressure. From pre-CPB to post-CPB, Ees increased in three patients with a decrease of V75 in two patients, and Ees decreased in four patients with a concomitant increase in V75. Ed increased significantly (P less than 0.01) following CPB, demonstrating a decrease of ventricular distensibility. It is concluded that continuous measurement of LV pressure-volume relationships using the conductance catheter is feasible and may be a useful tool to estimate LV performance during cardiac surgery.