title: Diagnostic accuracy of capnography during high-frequency ventilation in neonatal intensive care units.
abstract: OBJECTIVE
  High-frequency ventilation (HFV) is a powerful tool for CO2 elimination, and thus requires careful monitoring of CO2 . Our aim was to assess the diagnostic accuracy (correlation, agreement, and trending) of continuous distal capnography (dCap) with PaCO2 in infants ventilated with HFV.
  
  
  METHODS
  This was a prospective, observational, multicenter study. dCap was compared with simultaneous PaCO2 ("gold standard") drawn from indwelling arterial line for patient care in term and preterm infants ventilated with HFV. dCap was obtained via the side-port of a double-lumen endotracheal-tube by a Microstream capnograph with specially designed software for HFV.
  
  
  RESULTS
  Twenty-four infants participated in the study (median [range] gestational age [GA]: 26.8 [23.6-38.6] weeks). Analysis included 332 measurements. dCap was in correlation (r = 0.70, P < 0.001) but with less than adequate agreement (mean difference ± SD of the differences: -11.7 ± 10.3 mmHg) with PaCO2 . Comparable findings were found in the subgroup of infants <1,000 g (n = 240 measurements). Correlations were maintained in severe lung disease. Changes in dCap and in PaCO2 for consecutive measurements within each patient were correlated (r = 0.63, P < 0.001). Area under the receiver operating curves (ROC) for dCap to detect high (>60 mmHg) or low (<30 mmHg) PaCO2 was 0.83 (CI: 0.76-0.90) and 0.88 (CI: 0.79-0.97), respectively; P < 0.001.
  
  
  CONCLUSIONS
  Our prospective study suggests that continuous dCap in infants ventilated with HFV may be helpful for trends and alarm for unsafe levels of PaCO2 . dCap is only a complimentary tool and cannot replace PaCO2 sampling because the agreement between these measurements was less than adequate.
authors.affiliation: Department of Neonatology, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel.|Pediatric Pulmonary Unit, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel.
authors.forename: Amir
authors.initials: A
authors.lastname: Kugelman
authors.affiliation: Department of Neonatology, Shaare Zedek Medical Center, Faculty of Medicine of the Hebrew University, Jerusalem, Israel.
authors.forename: Ruben
authors.initials: R
authors.lastname: Bromiker
authors.affiliation: Department of Neonatology, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel.
authors.forename: Arieh
authors.initials: A
authors.lastname: Riskin
authors.affiliation: Department of Neonatology, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel.
authors.forename: Irit
authors.initials: I
authors.lastname: Shoris
authors.affiliation: Covidien, Respiratory and Monitoring Solutions, Jerusalem, Israel.
authors.forename: Michal
authors.initials: M
authors.lastname: Ronen
authors.affiliation: Department of Neonatology, Shaare Zedek Medical Center, Faculty of Medicine of the Hebrew University, Jerusalem, Israel.
authors.forename: Nelly
authors.initials: N
authors.lastname: Qumqam
authors.affiliation: Department of Neonatology, Bnai Zion Medical Center, The B&R Rappaport Faculty of Medicine, Technion, Haifa, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Bader
authors.affiliation: Department of Neonatology, Soroka Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel.
authors.forename: Agenta
authors.initials: A
authors.lastname: Golan
mesh_terms: D019296:Capnography; D002245:Carbon Dioxide / Q000032:analysis*; D005260:Female; D005865:Gestational Age; D006612:High-Frequency Ventilation; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D007363:Intensive Care Units, Neonatal; D008171:Lung Diseases / Q000175:diagnosis*; D008297:Male; D011446:Prospective Studies; D012121:Respiration, Artificial
chemical_list: D002245:Carbon Dioxide
keywords: Capnography; end tidal CO2; high-frequency ventilation; neonates