MAINSTREAM END-TIDAL CARBON-DIOXIDE MONITORING IN THE NEONATAL INTENSIVE-CARE UNIT

Citation
Hj. Rozycki et al., MAINSTREAM END-TIDAL CARBON-DIOXIDE MONITORING IN THE NEONATAL INTENSIVE-CARE UNIT, Pediatrics, 101(4), 1998, pp. 648-653
Citations number
32
Categorie Soggetti
Pediatrics
Journal title
ISSN journal
00314005
Volume
101
Issue
4
Year of publication
1998
Pages
648 - 653
Database
ISI
SICI code
0031-4005(1998)101:4<648:MECMIT>2.0.ZU;2-8
Abstract
Background. Continuous noninvasive monitoring of arterial carbon dioxi de (CO2) in neonatal intensive care unit (NICU) patients would help cl inicians avoid complications of hypocarbia and hypercarbia. End-tidal CO2 monitoring has not been used in this population to date, but recen t technical advances and the introduction of surfactant therapy, which improves ventilation-perfusion matching, might improve the clinical u tility of end-tidal monitoring. Objective. To determine the accuracy a nd precision of end-tidal CO2 monitoring in NICU patients. Design. Non randomized recording of simultaneous end-tidal and arterial CO2 pairs. Setting. Two university NICUs. Patients. Forty-five newborn infants r eceiving mechanical ventilation who had indwelling arterial access, an d a predefined subsample of infants who were <1000 g birth weight, <8 days of age, and who received surfactant therapy (extremely low birth weight [ELBW] <8). Outcome Measures. The correlation coefficient, degr ee of bias, and 95% confidence interval were determined for both the o verall population and the ELBW <8 subgroup. Those factors which signif icantly influenced the bias were identified. The ability of the end-ti dal monitor to alert the clinician to instances of hypocarbia or hyper carbia was determined. Results. There were 411 end-tidal/arterial pair s analyzed from 45 patients. The correlation coefficient was 0.833 and the bias was -6.9 mm Hg (95% confidence interval, +/- 11.5 mm Hg). Th e results did not differ markedly in the ELBW <8 infants. Measures of the degree of lung disease, the ventilation index and the oxygenation index, had small influences on the degree of bias. This type of capnom etry identified 91% of the instances when the arterial CO2 pressure wa s between 34 and 54 mm Hg using an end-tidal range of 29 to 45 mm Hg. End-tidal values outside this range had a 63% accuracy in predicting h ypocarbia or hypercarbia. Conclusion. End-tidal CO2 monitoring in NICU patients is as accurate as capillary or transcutaneous monitoring but less precise than the latter. It may be useful for trending or for sc reening patients for abnormal arterial CO2 values.