Performance of capnometry in non-intubated infants in the pediatric intensive care unit

Navigating Pediatric Capnography: A Comprehensive Review of Scope and Limitations

This review comprehensively explores pediatric capnography, a vital tool in contemporary respiratory monitoring. The overview encompasses the foundational principles of capnography, elucidating its real-time measurement of carbon dioxide (CO2) in respiratory gases. The review emphasizes its paramount role in pediatric care and underscores capnography's significance in detecting respiratory abnormalities and guiding timely interventions. The distinctions between mainstream and sidestream capnography, the key to understanding their applications, are meticulously outlined. Addressing the importance of ongoing research and education, the review advocates for a dynamic approach to refine guidelines and optimize capnography utilization in pediatric settings. The conclusion reflects on the scope and limitations of pediatric capnography, acknowledging its transformative impact while advocating for a judicious recognition of constraints. As we navigate the future of pediatric respiratory care, the synergy of research, education, and clinical application emerges as the cornerstone for advancing pediatric capnography to new horizons.

At-home end-tidal carbon dioxide measurement in children with invasive home mechanical ventilation

BACKGROUND

Carbon dioxide concentration trending is used in chronic management of children with invasive home mechanical ventilation (HMV) in clinical settings, but options for end-tidal carbon dioxide (EtCO₂ ) monitoring at home are limited. We hypothesized that a palm-sized, portable endotracheal capnograph (PEC) that measures EtCO₂ could be adapted for in-home use in children with HMV.

METHODS

We evaluated the internal consistency of the PEC by calculating an intraclass correlation coefficient of three back-to-back breaths by children (0-17 years) at baseline health in the clinic. Pearson's correlation was calculated for PEC EtCO₂ values with concurrent mean values of in-clinic EtCO₂ and transcutaneous CO₂ (TCM) capnometers. The Bland-Altman test determined their level of agreement. Qualitative interviews and surveys assessed usability and acceptability by family-caregivers at home.

RESULTS

CO₂ values were collected in awake children in varied activity levels and positions (N = 30). The intraclass correlation coefficient for the PEC was 0.95 (p < 0.05). The correlation between the PEC and in-clinic EtCO₂ device was 0.85 with a mean difference of -3.8 mmHg and precision of ±1.1 mmHg. The correlation between the PEC and the clinic TCM device was 0.92 with a mean difference of 0.2 mmHg and precision of ±1.0. Family-caregivers (N = 10) trialed the PEC at home; all were able to obtain measurements at home while children were awake and sometimes asleep.

CONCLUSIONS

A portable, noninvasive device for measuring EtCO₂ was feasible and acceptable, with values that trend similarly to currently in-practice, outpatient models. These devices may facilitate monitoring of EtCO₂ at home in children with invasive HMV.

Can Non-Invasive Capnography and Integrated Pulmonary Index Contribute to Patient Monitoring in the Pediatric Emergency Department?

OBJECTIVES

Noninvasive capnography (NICG) devices can measure oxygen saturation, end-tidal carbon dioxide (EtCO2), respiratory rate, heart rate values and integrated pulmonary index (IPI). This study aimed to evaluate patients who were monitored using NICG for various indications in a pediatric emergency department and to determine its contribution to patient management in the pediatric emergency department (PED).

METHODS

In this study, children aged <18 years who had been monitored with a NICG at the PED in our university between August 2018-May 2019 were evaluated. Of them 48 patients' file records and monitored capnography parameters such as heart rate, respiratory rate, blood pressure, capillary refill time, Glasgow Coma Score, SpO2, EtCO2, IPI recorded in the forms were reviewed.

RESULTS

Patients most often presented to the emergency room due to seizures (35.4%), change in consciousness (22.9%), other neurological reasons (18.8%) with %50 were female. Seizure treatment(16.7%), circulatory-respiratory support(16.7%), and antiedema treatments(6.3%) were required for 39.5% patients as life-saving interventions, and 72.9% patients were hospitalized. Patients with low IPI(<8) values at the beginning and decreasing IPI (<8) measurements within monitoring period needed more life-saving treatments(p=0.005 and p=0.001, respectively). Low IPI values of the patients during monitoring showed a significant difference in the decision to be hospitalized(p=0.048).

CONCLUSIONS

The results of the present study indicate that monitoring with NICG in the pediatric emergency room can be an important early indicator in establishing clinical prediction. The study particularly points out that the IPI value can be a guide in decisions regarding life-saving treatment and hospitalization. Among the capnographic data of these patients who had a change in consciousness IPI values those measured at the beginning and within the monitorizarion period showed a significant correlation with low GCS (<8) (r=0.478, p=0.001 and r=0.456, p=0.02, respectively). Prospective comprehensive large scale studies are needed to examine the use of NICG and IPI in routine PED practice for various indications.

Noninvasive Estimation of Arterial CO2 From End-Tidal CO2 in Mechanically Ventilated Children: The GRAeDIENT Pilot Study

OBJECTIVES

The aim of our pilot study was to develop a model to better predict Paco2 in mechanically ventilated children using noninvasive parameters including volumetric capnography.

DESIGN

Prospective clinical pilot study.

SETTING

Level III PICU.

PATIENTS

Sixty-five mechanically ventilated children.

INTERVENTIONS

None.

MATERIALS AND METHODS

We conducted a prospective clinical pilot study that included all children admitted to the PICU (< 18 yr; weight, > 3 kg; mechanically ventilated, > 6 hr; with an arterial line). A predictive model for PaCO2 was developed using linear multivariable regression. Among the data collected in PICU patients, candidate predictors of PaCO2 were defined by a panel of experts and included end-tidal partial pressure of carbon dioxide, ventilation parameters, and data resulting from the analysis of volumetric capnogram recorded 5 minutes before an arterial blood gas. Children with tidal volume less than 30 mL were excluded because of technical limits.

RESULTS

A total of 65 children (43 boys, 65%) (65 [21-150] mo old) were analyzed. By linear multivariable regression, the best model included the mean airway pressure, end-tidal partial pressure of carbon dioxide, FIO2, and the capnographic index with an R equal to 0.90, p value less than 0.001. After correction, 95% (n = 62) of children had an estimated PaCO2 at ± 5 mm Hg.

CONCLUSION

Our model developed provides an accurate estimation of the PaCO2 using end-tidal CO2 and noninvasive variables. Studies are needed to validate the equation in PICUs.

Current methodological and technical limitations of time and volumetric capnography in newborns

Although capnography is a standard tool in mechanically ventilated adult and pediatric patients, it has physiological and technical limitations in neonates. Gas exchange differs between small and adult lungs due to the greater impact of small airways on gas exchange, the higher impact of the apparatus dead space on measurements due to lower tidal volume and the occurrence of air leaks in intubated patients. The high respiratory rate and low tidal volume in newborns, especially those with stiff lungs, require main-stream sensors with fast response times and minimal dead-space or low suction flow when using side-stream measurements. If these technical requirements are not fulfilled, the measured end-tidal CO2 (P et CO 2 ), which should reflect the alveolar CO2 and the calculated airway dead spaces, can be misleading. The aim of this survey is to highlight the current limitations of capnography in very young patients to avoid pitfalls associated with the interpretation of capnographic parameters, and to describe further developments.