"New-generation" pulse oximeters in extremely low-birth-weight infants: how do they perform in clinical practice?

Alarm Safety and Alarm Fatigue

Clinical alarm systems have received significant attention in recent years following warnings from hospital accrediting and health care technology organizations regarding patient harm caused by unsafe practices. Alarm desensitization or fatigue from frequent, false, or unnecessary alarms, has led to serious events and even patient deaths. Other concerns include settings inappropriate to patient population or condition, inadequate staff training, and improper use or disabling. Research on human factors in alarm response and of functionality of medical devices will help clinicians develop appropriate policies, practices, and device settings for clinical alarms in neonatal intensive care units.

Performance of Two Different Pulse Oximeters in Neonatal Transition

OBJECTIVE

To evaluate the performance of two different pulse oximeter technologies by comparing the time taken to achieve reliable oxygen saturation readings during neonatal transition.

METHODS

This cross-sectional study was done to compare the performance of two pulse oximeter technologies - Signal Extraction Technology (SET), and Resistor Calibration (RCAL) technology on 150 inborn, term neonates at birth. Probes of both pulse oximeters were connected to the pre-ductal limb and the time taken to obtain a reliable reading was recorded. Sequential saturation values were recorded every minute till ten minutes of life. Statistical analysis was done with Mann-Whitney U test and intraclass correlation coefficient was calculated.

RESULTS

Pulse oximeter with SET recorded reliable readings faster than RCAL technology - Median (IQR) 32 (21-60)s vs. 45 (21.75-105)s, p = 0.021. There was a significant difference in the time to record first saturation readings of the two pulse oximeters when used in normal deliveries [RCAL vs. SET-Median (IQR) 50s (25-120.75) vs. 32.5s (21.75-58.25), p = 0.004] but no such difference was observed in Lower Segment Cesarean section (LSCS) [RCAL vs. SET Median (IQR) 35.5s (18.25-70.75) vs. 31s (20-69.75), p = 0.968]. Sequential saturation readings for every minute for the first 10 min of life were higher with SET vs. RCAL technology. The intraclass correlation coefficient between both pulse oximeters, for each minute, was poor (r < 0.80).

CONCLUSIONS

The SET pulse oximeter picked up first saturation values faster than the RCAL technology pulse oximeters. Studies are needed to evaluate effect of this on decisions made during neonatal resuscitation.

Performance Evaluation of New-Generation Pulse Oximeters in the NICU: Observational Study

This crossover observational study compares the data characteristics and performance of new-generation Nellcor OXIMAX and Masimo SET SmartPod pulse oximeter technologies. The study was conducted independent of either original equipment manufacturer (OEM) across eleven preterm infants in a Neonatal Intensive Care Unit (NICU). The SmartPods were integrated with Dräger Infinity Delta monitors. The Delta monitor measured the heart rate (HR) using an independent electrocardiogram sensor, and the two SmartPods collected arterial oxygen saturation (SpO2) and pulse rate (PR). All patient data were non-Gaussian. Nellcor PR showed a higher correlation with the HR as compared to Masimo PR. The statistically significant difference found in their median values (1% for SpO2, 1 bpm for PR) was deemed clinically insignificant. SpO2 alarms generated by both SmartPods were observed and categorized for performance evaluation. Results for sensitivity, positive predictive value, accuracy and false alarm rates were Nellcor (80.3, 50, 44.5, 50%) and Masimo (72.2, 48.2, 40.6, 51.8%) respectively. These metrics were not statistically significantly different between the two pulse oximeters. Despite claims by OEMs, both pulse oximeters exhibited high false alarm rates, with no statistically or clinically significant difference in performance. These findings have a direct impact on alarm fatigue in the NICU. Performance evaluation studies can also impact medical device purchase decisions made by hospital administrators.

MEchatronic REspiratory System SImulator for Neonatal Applications (MERESSINA) project: a novel bioengineering goal

Respiratory function is mandatory for extrauterine life, but is sometimes impaired in newborns due to prematurity, congenital malformations, or acquired pathologies. Mechanical ventilation is standard care, but long-term complications, such as bronchopulmonary dysplasia, are still largely reported. Therefore, continuous medical education is mandatory to correctly manage devices for assistance. Commercially available breathing function simulators are rarely suitable for the anatomical and physiological realities. The aim of this study is to develop a high-fidelity mechatronic simulator of neonatal airways and lungs for staff training and mechanical ventilator testing. The project is divided into three different phases: (1) a review study on respiratory physiology and pathophysiology and on already available single and multi-compartment models; (2) the prototyping phase; and (3) the on-field system validation.

Implementation of artifact detection in critical care: a methodological review

Artifact detection (AD) techniques minimize the impact of artifacts on physiologic data acquired in critical care units (CCU) by assessing quality of data prior to clinical event detection (CED) and parameter derivation (PD). This methodological review introduces unique taxonomies to synthesize over 80 AD algorithms based on these six themes: 1) CCU; 2) physiologic data source; 3) harvested data; 4) data analysis; 5) clinical evaluation; and 6) clinical implementation. Review results show that most published algorithms: a) are designed for one specific type of CCU; b) are validated on data harvested only from one OEM monitor; c) generate signal quality indicators (SQI) that are not yet formalized for useful integration in clinical workflows; d) operate either in standalone mode or coupled with CED or PD applications; e) are rarely evaluated in real-time; and f) are not implemented in clinical practice. In conclusion, it is recommended that AD algorithms conform to generic input and output interfaces with commonly defined data: 1) type; 2) frequency; 3) length; and 4) SQIs. This shall promote: a) reusability of algorithms across different CCU domains; b) evaluation on different OEM monitor data; c) fair comparison through formalized SQIs; d) meaningful integration with other AD, CED and PD algorithms; and e) real-time implementation in clinical workflows.

Observing the resuscitation of very preterm infants: are we able to follow the oxygen saturation targets?

BACKGROUND

Since 2010, the European Resuscitation Council (ERC) guidelines advise oxygen saturation (SpO2) targets for the first 10 min of resuscitation after birth. Unfortunately, the control of SpO2 in newborn infants is difficult.

AIM

To determine to what extent SpO2 levels match the ERC targets during the resuscitation of very preterm infants, and how well the SpO2 is kept within the high and low limits until the infants are transported to the NICU.

METHODS

In a single-centre observational study, the SpO2 and fraction of inspired oxygen (FiO2) were collected during the resuscitation of very preterm infants with a gestational age (GA)≤ 30 weeks.

RESULTS

A total of 78 infants were included [median (IQR): GA 27(4)/7 (26-28(6)/7) weeks, birth weight 945 g (780-1140)]. During the initial 10 min after birth, large variations in SpO2 were observed with deviations above the target [median (IQR)] of 4.4% SpO2 (1.4-6.5), and below the target of 8.2% SpO2 (2.8-16.0). After the first 10 min, the SpO2 levels were respectively above and below the limit for 11% (0-27) and 8% (0-23) of the time.

CONCLUSION

During the resuscitation of very preterm infants, large deviations of the SpO2 from the ERC targets are observed. During the first minutes of resuscitation the deviations were likely caused by an inability to control the SpO2, whereas later deviations were due to weaning, pauses in respiratory support (i.e. intubation) and over exposure to oxygen. Changing the SpO2 targets to a target range that depicts the acceptable deviation might be helpful in providing better respiratory support.