Normalization of hypertensive responses during ambulatory surgical stress by perioperative music.

OBJECTIVE: The purpose of this study was to determine whether cognitive appraisals of stress level and hypertensive responses to ambulatory ophthalmic surgery can be ameliorated by patient-selected music. METHODS: We studied 40 elderly individuals requiring ophthalmic surgery, 20 in an experimental group (mean age, 74 years) and 20 in a control group (mean age, 77 years). All patients had an established resting blood pressure <140/90 mm Hg. In the experimental group self-selected music was provided by headphones throughout the preoperative, surgical, and postoperative periods. In the control group patients had neither headphones nor music. All patients received similar (weight-determined) doses of alfentanil and midazolam during surgery. Heart rate, blood pressure, and patient-reported stress and coping levels were the dependent variables. RESULTS: In both groups, blood pressure values were normal (approximately 129/82 mm Hg) during screening examinations 1 week before surgery. On the day of surgery both groups displayed increased preoperative blood pressures (approximately 159/92 mm Hg) associated with increases in heart rate (by approximately 17 beats/min). Intraoperative blood pressures in the experimental group returned quickly to screening baseline values, whereas the control group experienced persistent elevations in intraoperative blood pressure similar to preoperative levels. Over the course of the surgical experience, patients with music reported significant reductions in perceived stress and increases in coping abilities (p < .001), whereas those without music did not. CONCLUSIONS: The perceived stress of ambulatory surgery in geriatric patients is associated with a clinical hypertensive response that is ameliorated by self-selected perioperative music, which also decreases perceived stress and increases patients' sense of personal control and well-being.

Lidocaine absorption and metabolism after oropharyngeal application in young and young-elderly adults.

The purpose of this study was to evaluate the effect of age on lidocaine absorption and metabolism after application to the oropharynx and vocal cords in a manner similar to preparation for flexible fiberoptic bronchoscopy. Five healthy volunteers were studied in each of two age groups: from 25 to 37 and 60 to 68 years of age. Each volunteer had a total of lidocaine 300 mg administered as a gargle, gel, or directly to the vocal cords. Blood samples and expectorant were collected to determine concentrations of lidocaine and its metabolites, monoethylglycinxylidide (MEGX) and glycinxylidide (GX). No differences in peak plasma lidocaine concentrations, 2.09 +/- 1.28 mumol/L (1 microgram/mL = 4.27 mumol/L) in young subjects, and 2.35 +/- 0.85 mumol/L in young-elderly subjects, or lidocaine AUC were seen between the two age groups. Lidocaine recovered in expectorant ranged from 96 to 168 mg. This study suggests that, over the age range studied, increased age does not impair lidocaine absorption from the oropharynx or lidocaine metabolism when topical lidocaine is used during flexible fiberoptic bronchoscopy.

Lack of effect of piroxicam on theophylline clearance in healthy volunteers.

This study was conducted to determine if piroxicam alters the clearance or metabolism of theophylline in healthy adults. Six male volunteers were given aminophylline 6 mg/kg iv before and after piroxicam treatment. Piroxicam 20 mg/d po was administered for seven days. Serum samples were collected before and for 24 hours after each aminophylline dose. Theophylline serum concentrations were determined using the Abbott TDx automated immunoassay system. Theophylline and its 1,3-dimethyluric acid metabolite were measured in 24-hour urine collections. Serum theophylline concentration versus time curves were plotted and pharmacokinetic parameters determined for each subject. None of the derived parameters differed as a result of piroxicam exposure. Theophylline metabolites, clearance, half-life, and volume of distribution were compared during the baseline and piroxicam phases and were found to be similar. It was concluded that piroxicam does not alter the clearance, distribution, volume, or metabolism of theophylline in healthy adult volunteers.

Large surface area activated charcoal and the inhibition of aspirin absorption.

Activated charcoal's adsorptive capacity, and therefore potential efficacy, is generally related to its surface area. In our study, the efficacy of two activated charcoal preparations, Actidose-Aqua 1,500 m2/g and Super Char, 3,000 m2/g, were compared on the basis of their ability to inhibit aspirin absorption. Twelve healthy male subjects fasted for eight hours before and four hours after a 20 mg/kg oral dose of aspirin. One hour after aspirin dosing, each subject received either no charcoal, 25 g Actidose-Aqua, or 25 g Super Char in a randomized crossover design. Each aspirin dose was separated from the previous dose by at least seven days. Total urine volumes were collected over 12-hour intervals, beginning 12 hours before the aspirin dose and continuing for 72 hours after dosing. Urine salicylate concentration was measured with a colorimetric assay. The fraction of aspirin dose recovered in the urine was 0.96 +/- 0.13, 0.78 +/- 0.18, and 0.50 +/- 0.20 for the control, Actidose-Aqua, and Super Char treatment phases, respectively. In vitro, Super Char was found to bind more salicylic acid than Actidose-Aqua at pH 8.1. We conclude that both activated charcoal preparations significantly reduced the gastrointestinal absorption of aspirin (P less than .05) and that Super Char was significantly more effective than Actidose-Aqua in reducing the gastrointestinal absorption of aspirin (P less than .01).

The increase in urinary alanine aminopeptidase excretion associated with enflurane anesthesia is increased further by aminoglycosides.

Urinary excretion of alanine aminopeptidase (AAP) is an extremely sensitive indicator of drug-induced renal tubular damage. The urinary excretion of AAP was determined in patients after enflurane anesthesia with or without concurrent aminoglycoside administration to determine if enflurane enhances the nephrotoxic potential of aminoglycosides. Twenty-two patients with normal renal function were studied. Ten received enflurane alone, eight received enflurane plus gentamicin or tobramycin, and four patients who underwent nitrous oxide and narcotic anesthesia were the control group. Preoperative values ranged from 1010 to 2461 microU/24 hour. Urinary AAP excretion increased significantly in both enflurane groups 2 days postoperatively (P less than 0.025). Patients who received both enflurane and aminoglycosides had significantly greater urinary AAP excretion on postoperative day 2 than did patients given enflurane alone: 21,342 +/- 4074 microU/24 hour and 6336 +/- 1496 microU/24 hour, respectively (mean +/- SEM, P less than 0.005). There was no change in AAP excretion in the control group compared to baseline; on day 3 AAP was 1412 +/- 710 microU/24 hour. No changes in blood urea nitrogen or serum creatinine levels were observed. These data suggest that enflurane increases the renal tubular effects of aminoglycosides, possibly increasing the risk of aminoglycoside renal toxicity.

Unpredictable anaphylactic reaction to protamine sulfate.

Anaphylactic reactions to protamine administration often can be predicted by the presence of patient risk factors. In the case described, an anaphylactic reaction to protamine occurred in a patient without identifiable risk factors. A history of prior protamine exposure, fish allergy, or vasectomy suggests patients may be at greater risk for anaphylactic response to protamine; however, patients can develop anaphylaxis in the absence of such factors.