Paediatric preoperative teaching: effects at induction and postoperatively.

In a randomized controlled trial at Duke University and University of North Carolina Hospitals, 143 two to six year old children undergoing elective ambulatory surgery were randomized into a control group who received routine preoperative teaching or an intervention group who received an interactive teaching book. Changes in behaviour were measured by a Vernon behavioural questionnaire preoperatively and again two weeks postoperatively. A Global Mood Score was assessed in the preoperative holding area, at arrival into the operating room, and at the time of mask induction. The children in the control group were significantly more aggressive postoperatively than the intervention group (P < 0.05). Children who received the interactive teaching book exhibited higher levels of anxiety on the day of surgery, but fewer behavioural changes two weeks following surgery. Parents in the intervention group reported that preoperative teaching helped their child (87%) and themselves (83%).

Onset and recovery of neuromuscular blockade after two doses of rocuronium in children.

STUDY OBJECTIVE: To determine if 450 micrograms/kg (1.5 times the ED95) of rocuronium would result in a comparable onset with a shorter duration of action when compared with 600 micrograms/kg (2 times the ED95). DESIGN: Randomized, single-blind study. SETTING: Teaching hospital. PATIENTS: 85 ASA physical status I and II children ages 2 through 12, undergoing elective surgery with an inhalation induction using halothane. INTERVENTIONS: Group 1 received 600 micrograms/kg rocuronium, and Group 2 received 450 micrograms/kg rocuronium. MEASUREMENTS AND MAIN RESULTS: The two groups were compared using a Student's t-test, with p < 0.05 significant. The time of onset, or time to 95% suppression of neuromuscular twitch with standard errors, was 140 +/- 13 seconds (range 46 to 365 sec) in Group 1 and 148 +/- 13 seconds (range 82 to 345 sec) in Group 2 (NS = not significant). The times to 25% return of twitch from baseline (T25) in Groups 1 and 2 were 28 +/- 1.5 minutes (range 14 to 45 min) and 26 +/- 1.6 minutes (range 10 to 55 min), respectively (NS). The differences between these two doses in onset of, and recovery from, block were not found to be statistically significant. The results, however, excluded 5% of the higher dose group and 31% of the lower dose group who did not achieve 95% suppression of twitch. Time to maximal suppression of neuromuscular blockade, however, was not statistically significant for the 85 patients with a time of 270 +/- 28 seconds (range 91 to 605 sec) with a mean maximal suppression of 98.7% in Group 1 and 313 +/- 25 seconds (range 91 to 899 sec) with a mean maximal suppression of 93.1% in Group 2. CONCLUSION: The two doses of rocuronium did not differ statistically in onset or duration. Rocuronium at 600 micrograms/kg offers more reliability than 450 micrograms/kg in achieving adequate muscle relaxation, and the lower dose may result in a significantly large number of patients who may have inadequate intubating conditions.

The successful implementation of pharmaceutical practice guidelines. Analysis of associated outcomes and cost savings. SWiPE Group. Systematic Withdrawal of Perioperative Expenses.

BACKGROUND: Although approximately 2,000 medical practice guidelines have been proposed, few have been successfully implemented and sustained. We hypothesized that we could develop and institute practice guidelines to promote more appropriate use of costly anesthetics, to generate and sustain widespread compliance from a large physician group, and to decrease costs without adversely affecting clinical outcomes. METHODS: A prospective before and after comparison study was performed at a tertiary care medical center. Clinical outcomes data and times indicative of perioperative patient flow were collected on the first of two sets of patients 1 month before discussion of practice guidelines. Practice guidelines were developed by the physicians and their associated care team for the intraoperative use of anesthetic drugs. A drug distribution process was developed to aid compliance. Clinical outcomes data and times indicative of perioperative patient flow were collected on the second set of patients 1 month after institution of practice guidelines. Hospital drug costs and adherence to guidelines were noted throughout the study period and for each of the following 9 months by querying the database of an automated anesthesia record keeper. RESULTS: A total of 1,744 patients were studied. Drug costs decreased from 56 dollars per case to 32 dollars per case as a result of adherence to practice guidelines. Perioperative patient flow was minimally affected. Time (mean +/- SD) from end of surgery to arrival in the post-anesthesia care unit (PACU) increased from 11 +/- 7 min before the authors instituted practice guidelines to 14 +/- 8 min after practice guidelines (P < 0.0001). Admission of inpatients to the PACU receiving monitored anesthesia care increased from 6.5 to 12.9% (P < 0.02). Perioperative patient flow and clinical outcomes were not otherwise adversely affected. Compliance and cost savings have been sustained. CONCLUSIONS: This study is an example of a successful physician-directed program to promote more appropriate utilization of health care resources. Cost savings were obtained without any substantial changes in clinical outcomes. Institution of similar practice guidelines should result in pharmaceutical savings in the range of 50% at tertiary care centers around the country, with a slightly smaller degree of savings expected at institutions with more ambulatory surgery.

Using an anesthesia information management system as a cost containment tool. Description and validation.

BACKGROUND: Medical informatics provide a new way to evaluate the practice of medicine. Anesthesia automated record keepers have introduced anesthesiologists to computerized medical records. To derive useful information from the stored data requires programming that is not currently commercially available. The authors describe how they custom-programmed an automated record keeper's database to perform cost calculations, how they validated the programming, and how they used the data in a successful pharmaceutical cost-containment program. METHODS: The Arkive (San Diego, CA) automated record keeper database was programmed at Duke University Medical Center as an independent noncommercial project to calculate costs according to standard formulae and to follow adherence to Duke University Department of Anesthesiology's prescribing guidelines for anesthetic drugs. Validation of that programming (including analysis of discarded drugs) was accomplished by comparing database calculated costs with actual pharmacy distribution of drugs during a 1-month period. RESULTS: Validation data demonstrated a 99% accuracy rate for total costs of the drugs studied (atracurium, vecuronium, rocuronium, propofol, midazolam, fentanyl, and isoflurane). The study drugs represented approximately 67% of all drug costs for the period studied. CONCLUSIONS: Programming of an anesthesia automated record keeper's database yields essential information for management of an anesthetic practice. Accurate economic evaluation of anesthetic drug use is now possible. In the future, as definitive identification of best anesthetic practices that yield optimal patient outcomes and higher measures of patient satisfaction is pursued, large numbers of patients should be studied. This is only possible through database analysis and complete computerization of the perioperative medical record.

Pharmacokinetic model-driven infusion of fentanyl in children.

BACKGROUND: This study determined the accuracy of previously defined adult fentanyl pharmacokinetics in children having surgery; from this population, the pharmacokinetics of fentanyl were characterized in children when administered via a computerized assisted continuous-infusion device. METHODS: Twenty children between the ages of 2.7 and 11 y scheduled to undergo elective noncardiac surgery were studied. After induction, anesthesia was maintained with 60% nitrous oxide in oxygen supplemented with fentanyl (n = 10) or fentanyl plus isoflurane (n = 10). Fentanyl was administered via computerized assisted continuous-infusion to target concentrations determined by clinical requirements. Plasma fentanyl concentrations were measured and used to evaluate the performance of the fentanyl pharmacokinetics and then to determine a new set of pharmacokinetic parameters and the variance in the context-sensitive half-times simulated for these patients. RESULTS: The original adult fentanyl pharmacokinetics resulted in a positive bias (10.4%), indicating that measured concentrations were mostly greater than predicted. A two-compartment model with age and weight as covariates provided the optimal pharmacokinetic parameters. These resulted in a residual performance error of -1.1% and a median absolute performance error of 17.4%. The context-sensitive times determined from this pediatric population were considerably shorter than the context-sensitive times previously published for adults. CONCLUSIONS: The pharmacokinetics of fentanyl administered by computerized assisted continuous-infusion differ between adults and children. The newly derived parameters are probably more suitable to determine infusion schemes of up to 4 h in children between the ages of 2 and 11 y.

Gas exchange in abdominal cavity during laparoscopy.

Gas exchange occurring in the abdominal cavity during laparoscopy, using carbon dioxide as the insufflating gas, was investigated in 25 female patients being ventilated with 66.6% nitrous oxide and 33.3% oxygen. The gas remaining in the abdomen at the end of the procedure was collected and measurements were made using an infrared spectrometer, a paramagnetic analyser and a mass spectrometer. The mean duration of the laparoscopy was 9.5 minutes and the mean volume of carbon dioxide delivered was 6.8 litres. Nitrous oxide concentration in the abdomen was found to increase significantly with the duration of the procedure, varying from 1.4% to 12.8% with a mean of 4.3% (s.d. +/- 2.4). Oxygen concentration measured from 0.1 to 1.8% with a mean of 0.7% (s.d. +/- 0.4). Nitrogen concentration varied from zero to 1.8%, having a mean concentration of 0.8% (s.d. +/- 0.5). Carbon dioxide content was from 85.7 to 99.6% with a mean concentration of 94.2% (s.d. +/- 3.1).