Effects of atipamezole on selected physiologic parameters in cynomolgus macaques (Macaca fascicularis).

BACKGROUND: Atipamezole, an α-2 adrenergic receptor antagonist, reverses the α-2 agonist anesthetic effects. There is a dearth of information on the physiological effects of these drugs in cynomolgus macaques (Macaca fascicularis). We assessed atipamezole's physiologic effects. We hypothesized atipamezole administration would alter anesthetic parameters. METHODS: Five cynomolgus macaques were sedated with ketamine/dexmedetomidine intramuscularly, followed 45 min later with atipamezole (0.5 mg/kg). Anesthetic parameters (heart rate, blood pressure [systolic (SAP), diastolic (DAP), and mean (MAP) blood pressure], body temperature, respiratory rate, and %SpO2) were monitored prior to and every 10 min (through 60 min) post atipamezole injection. RESULTS: While heart rate was significantly increased for 60 min; SAP, DAP, MAP, and temperature were significantly decreased at 10 min. CONCLUSIONS: This study indicates subcutaneous atipamezole results in increased heart rate and transient blood pressure decrease. These findings are clinically important to ensure anesthetist awareness to properly support and treat patients as needed.

Childhood farm injuries in Old-Order Amish families.

Unintentional injuries are the leading cause of death and disabilities in the United States among children, with the incidence even greater among children who live on a farm. Information exists about farming accidents on mainstream U.S. farms; however, little is known about the Amish farms. The purpose of this study was to investigate injuries among Old-Order Amish in Pennsylvania. Teachers in Amish schools were surveyed about their experiences with accidents/injuries among children on the farm. Seventy percent of the teachers reported a childhood farm injury in their family, with the majority attributing this to farm animals. Injuries may be preventable if age-appropriate tasks are assigned to children and they are properly supervised.

Posthospital home care for frail older adults in rural locations.

After discharge from the hospital, older patients often require continued home care, including both professional and nonprofessional services. These needs can be exacerbated by health status (i.e., frailty) and geographic residence (i.e., rurality). It was the purpose of this study to examine patterns of postdischarge home care and outcomes for frail elders from rural locations. Seventy frail older adults being discharged from an acute urban-based hospital to home in a rural setting were recruited. Baseline data were collected before discharge from the hospital, and then calls were made at 48 hr and 2 and 4 weeks after discharge to evaluate use of resources and out-of-pocket expenses. Nonprofessional services were used most frequently, and the most intense time of use was at the 2-week postdischarge period. These findings suggest that discharge planning should include obtaining information about availability of both professional and nonprofessional services in the home community and arranging for appropriate delivery of both.

Absorption of phenytoin from rectal suppositories formulated with a polyethylene glycol base.

STUDY OBJECTIVE: To compare phenytoin pharmacokinetics following administration of an oral suspension and a rectal suppository formulated with a polyethylene glycol base. DESIGN: Unblinded, single-dose, randomized, crossover trial. SETTING: University-affiliated pharmacokinetics and biopharmaceutics laboratory. SUBJECTS: Six healthy subjects. INTERVENTION: Subjects were given a single 200-mg dose of phenytoin as an oral suspension and a rectal suppository separated by a 1-week washout. MEASUREMENTS AND MAIN RESULTS: Blood for plasma phenytoin concentrations was obtained at baseline and 0.5, 1, 2, 4, 6, 8, 10, 12, and 24 hours after administration. Plasma was analyzed by high-performance liquid chromatography (coefficient of variation < 6%) for total phenytoin concentration. Phenytoin maximum concentration (Cmax), time to Cmax (Tmax), time to first measurable concentration (Tlag), and area under the curve from time zero to time of last measurable concentration (AUClast) were estimated for oral and rectal administration by WinNonlin (v 1.1) and compared using Wilcoxon's signed rank test (p<0.05 for statistical significance). Two subjects did not have detectable plasma phenytoin concentrations after rectal administration. For the other four subjects, median rectal Cmax was significantly lower than oral Cmax (0.4 vs 1.9 microg/ml, p=0.028), median rectal Tmax did not differ from oral Tmax (11.9 vs 8.0 hrs, p=0.465), and median rectal AUClast, although highly variable, was significantly lower than oral AUClast (5.4 vs 36.2 microg x hr/ml, p=0.046). No Tlag was seen after oral administration, but with rectal administration the median Tlag was 2 hours. The estimated relative bioavailability of rectal phenytoin suppositories based on AUC0-24 was 4.7%, with individual values ranging from 0-58.3%. CONCLUSION: It appears that absorption of phenytoin from polyethylene glycol rectal suppositories in healthy subjects is highly variable and unpredictable. Thus this formulation is not recommended.

The frequency of asymptomatic and electrically silent exercise-induced regional myocardial ischemia during first-pass radionuclide angiography with upright bicycle ergometry.

The presence of asymptomatic (silent) myocardial ischemia during provocative testing may limit the detection of ischemic heart disease, unless sensitive indicators of ischemia are utilized. Exercise ventricular function studies are well suited for ischemia detection since segmental dysfunction is an early pathophysiologic event in the ischemic cascade. In this study, we examined the rest and stress first-pass radionuclide angiographic studies of 104 patients with coronary artery disease and exercise-induced regional wall motion abnormalities. Asymptomatic ischemia was observed in 83 patients, while only 21 patients were symptomatic. Clinical variables were not different between the two groups, except for a higher frequency of a prior anginal history in the symptomatic group. The peak heart rate and pressure-rate product were significantly higher in the silent ischemia group, as these patients are not limited by symptoms. Wall motion scores, resting and exercise ejection fractions were similar in the two groups. The frequency of an ischemic electrocardiographic ST-segment response was low, and was not significantly different between groups. These data indicate that electrically and symptomatically silent myocardial ischemia are frequent occurrences with upright bicycle ergometry. Without adjunctive cardiac imaging, this mode of exercise may not be appropriate for the evaluation of ischemic heart disease.