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Published on: April 29, 2013
Age and the onset of desaturation in apnoeic children
R Patel1, M Lenczyk, R S Hannallah
1Department of Anesthesiology, Children's National Medical Center, Washington, D.C. 20010.
Insights
Apnoeic infants desaturate faster than older children and adolescents during anesthesia. This study shows oxygen saturation decline time increases with age in healthy pediatric patients.
Area of Science:
- Anesthesiology
- Pediatric Critical Care
Background:
- Patients undergoing general anesthesia are typically apneic during airway manipulation.
- Understanding desaturation times is crucial for safe pediatric anesthesia.
Purpose of the Study:
- To determine the onset of desaturation after pre-oxygenation in apneic infants, children, and adolescents.
- To correlate desaturation time with patient age.
Main Methods:
- Fifty healthy pediatric patients (2 days to 18 years) were stratified into five age groups.
- Following anesthesia induction and paralysis, mask ventilation with oxygen was maintained.
- The time from mask removal to a decrease in oxygen saturation (SpO2) to 90% was measured.
Main Results:
- Desaturation occurred significantly earlier in infants (0-6 months) compared to 2-5 year olds (96.5s vs 160.4s).
- Children (2-5 years) desaturated faster than adolescents (11-18 years) (160.4s vs 382.4s).
- A strong positive correlation was found between age and the time to reach 90% SpO2 (r² = 0.88).
Conclusions:
- The time to desaturation following pre-oxygenation increases with age in healthy pediatric patients.
- Age is a significant factor influencing the duration of safe apnea after pre-oxygenation in children.
Abstract:
Most patients undergoing general anaesthesia are apnoeic during laryngoscopy and tracheal intubation. This study determined the time until the onset of desaturation following pre-oxygenation in apnoeic infants, children, and adolescents. Fifty ASA physical status I patients, 2 days to 18 yr of age, were studied. The patients were stratified into one of five groups according to age: Group I, 0-6 mo; Group II, 7-23 mo; Group III, 2-5 yr; Group IV, 6-10 yr; and Group V, 11-18 yr. Following induction of anaesthesia with halothane via mask or intravenous barbiturates, the ability of the anaesthetist to ventilate the lungs via the mask was ascertained and paralysis was accomplished with vecuronium 0.1 mg.kg-1. Manual mask ventilation was maintained with oxygen and halothane. When end-tidal N2 decreased below 3% (minimum time two minutes), the face mask was removed. The time between the removal of the face mask and a decrease in oxygen saturation (SpO2) from 99-100% to 90% was measured. Manual ventilation was then resumed and the trachea intubated. Desaturation started earlier in infants than in two- to five-year-old children (96.5 +/- 12.7 sec vs 160.4 +/- 30.7 sec, P < 0.0001). Children became desaturated faster than adolescents (160.4 +/- 30.7 vs 382.4 +/- 79.9 sec, P < 0.0001). The time required to reach 90% saturation correlated well with age by linear regression analysis (r2 = 0.88, P < 0.0001). We conclude that the time to onset of desaturation following pre-oxygenation with mask ventilation increases with age in healthy apnoeic children.(ABSTRACT TRUNCATED AT 250 WORDS)
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