Inhalational anaesthetic exposure; screening for bleeding disorders; hand hygiene; Staphylococcus aureus infections - Evidence For Practice

AORN Journal, Jan, 2004 by George Allen

Surgical team members' exposure to inhalational anesthetics

Annals of Thoracic Surgery June 2003

Threshold values for exposure to waste anesthetic gases, including nitrous oxide, have been established; however, the debate about whether chronic exposure to these gases results in negative health effects in health care workers continues. The objective of this study was to determine the occupational exposure of perfusionists, cardiac surgeons, and anesthesiologists to nitrous oxide and other volatile agents, such as sevoflurane and desflurane, when they are used before cardiopulmonary bypass (CPB) procedures. (1)

Ten adult patients undergoing elective coronary artery bypass grafting using CPB were induced and maintained with nitrous oxide and sevoflurane or desflurane until the beginning of CPB. Samples of the ambient air in the breathing zone of the perfusionists, surgeons, and anesthesiologists were collected every 90 seconds throughout the procedures, and simultaneous measurements of the anesthetic gas concentrations at both outlet nozzles of the oxygenator were performed. Time weighted averages during the time of exposure were calculated.

Findings. The average concentration of anesthetic gases was low in the breathing zones of both the anesthesiologists and surgeons before CPB. The National Institute of Safety and Health (NIOSH) average time-weighted threshold value of 25 parts per million (ppm) for nitrous oxide was not violated at any time for the perfusionists, cardiac surgeons, and anesthesiologists. The desflurane load exposure findings for the surgeons increased significantly during CPB, however, and exceeded the NIOSH limit of 0.5 ppm during concomitant use of nitrous oxide.

Clinical implications. This study revealed that although waste anesthetic gas concentrations were measurable during procedures, the average time-weighted threshold value was not exceeded for nitrous oxide. When both nitrous oxide and desflurane were used, however, the threshold was exceeded. Perioperative nurses were not specifically monitored in this study, but the scrub person works in close proximity to the surgeon and, consequently, shares the same risk of exposure. Perioperative nurses should ensure that the ventilation system in the OR is functioning adequately and that waste scavenging systems on CBP equipment are used routinely.

Preoperative screening for breeding disorders in pediatric patients

Clinical Pediatrics April 2003

This retrospective study was conducted to determine if preoperative screening is useful in identifying bleeding disorders in pediatric patients. (2) Records were reviewed for 3,950 pediatric hematology outpatients, and 131 children were identified as having been referred for a prolonged preoperative activated partial thromboplastin (aPTT) level. Biographical data, family history of bleeding, aPTT performed by the referring pediatrician, evaluation performed by the hematologist, and the incidence of bleeding were abstracted from the records. The families of the children were contacted to identify patients who suffered postoperative bleeding. Additionally, the pediatricians and surgeons were asked to review their surgical records and postoperative follow-up notes to verify surgical outcomes. Common statistical measures were employed for comparisons.

Findings. Twenty-eight children (21%) with a prolonged preoperative aPTT were found to have a previously undiagnosed bleeding disorder. Seventy-five percent of the 28 did not have a personal history of a bleeding disorder, and 83% did not have a family history of a bleeding disorder. The most frequent bleeding disorders were von Willebrand disease (11%) and factor XI deficiency (6%). Two patients had factor VIII or vitamin K deficiency, one patient had liver disease, and one patient had circulating anticoagulant. None of the patients experienced perioperative bleeding complications.

Clinical implications. The study showed that preoperative screening with prothrombin time (PT) and aPTT is useful in identifying occult bleeding disorders. Such diagnosis would result in appropriate preoperative management and the reduction in hemorrhagic complications. If PT and aPTT assessments are not done routinely on pediatric patients scheduled for surgery, perioperative nurses should bring the results of this study to the attention of surgeons and anesthesia care providers.

Comparison of hand hygiene methods and effects of ring wearing on hand contamination

Clinical Infectious Diseases June 1, 2003

As health care workers' perform their duties, their hands easily become contaminated. Consequently, hand hygiene is an important process in preventing the transmission of infections. This study assessed risk factors for hand carriage of potential nosocomial pathogens and evaluated the efficacy of three hand hygiene methods--hand hygiene using an alcohol-based hand rub with 62% ethyl alcohol; hand hygiene using a medicated hand wipe measuring 15 cm by 19 cm formulated with an antibacterial substrate, including 0.1% benzalkonium chloride; and hand washing with plain soap and water. (3) A convenience sample of nurses participated in the study. A single hand of each participant was cultured during routine working hours on a surgical intensive care unit after a patient care episode. The nurses then were assigned randomly to one of the three hand hygiene methods. After hand hygiene, the participant's other hand was cultured. Concurrent data, including skin condition, dominant hand, glove use immediately before sampling, presence and number of rings, and length and type of fingernails also were collected. Logistic regression models and univariate analysis were used to analyze the data.