Amber L. Williams

Team Training in the Neonatal Resuscitation Program for Interns: Teamwork and Quality of Resuscitations

OBJECTIVE: Poor communication and teamwork may contribute to errors during neonatal resuscitation. Our objective was to evaluate whether interns who received a 2-hour teamwork training intervention with the Neonatal Resuscitation Program (NRP) demonstrated more teamwork and higher quality resuscitations than control subjects. METHODS: Participants were noncertified 2007 and 2008 incoming interns for pediatrics, combined pediatrics and internal medicine, family medicine, emergency medicine, and obstetrics and gynecology (n = 98). Pediatrics and combined pediatrics/internal medicine interns were eligible for 6-month follow-up (n = 34). A randomized trial was conducted in which half of the participants in the team training arm practiced NRP skills by using high-fidelity simulators; the remaining practiced with low-fidelity simulators, as did control subjects. Blinded, trained observers viewed video recordings of high-fidelity–simulated resuscitations for teamwork and resuscitation quality. RESULTS: High-fidelity training (HFT) group had higher teamwork frequency than did control subjects (12.8 vs 9.0 behaviors per minute; P < .001). Intervention groups maintained more workload management (control subjects: 89.3%; low-fidelity training [LFT] group: 98.0% [P < .001]; HFT group: 98.8%; HFT group versus control subjects [P < .001]) and completed resuscitations faster (control subjects: 10.6 minutes; LFT group: 8.6 minutes [P = .040]; HFT group: 7.4 minutes; HFT group versus control subjects [P < .001]). Overall, intervention teams completed the resuscitation an average of 2.6 minutes faster than did control subjects, a time reduction of 24% (95% confidence interval: 12%–37%). Intervention groups demonstrated more frequent teamwork during 6-month follow-up resuscitations (11.8 vs 10.0 behaviors per minute; P = .030). CONCLUSIONS: Trained participants exhibited more frequent teamwork behaviors (especially the HFT group) and better workload management and completed the resuscitation more quickly than did control subjects. The impact on team behaviors persisted for at least 6 months. Incorporating team training into the NRP curriculum is a feasible and effective way to teach interns teamwork skills. It also improves simulated resuscitation quality by shortening the duration.

Noise in contemporary neonatal intensive care

Weekly sound surveys (n = 63) were collected, using 5 s sampling intervals, for two modern neonatal intensive care units (NICUs). Median weekly equivalent sound pressure levels (LEQ) for NICU A ranged from 61 to 63 dB (A weighted), depending on the level of care. NICU B L(EQ) measurements ranged from 55 to 60 dB (A weighted). NICU B was recently built with a focus on sound abatement, explaining much of the difference between the two NICUs. Sound levels exceeded 45 dB (A weighted), recommended by the American Academy of Pediatrics, more than 70% of the time for all levels of care. Hourly L(EQ)s below 50 dB (A weighted) and hourly L10s below 55 dB (A weighted), recommended by the Sound Study Group (SSG) of the National Resource Center, were also exceeded in more than 70% of recorded samples. A third SSG recommendation, that the 1 s L(MAX), should not exceed 70 dB (A weighted), was exceeded relatively infrequently (< 11% of the time). Peak impulse measurements exceeded 90 dB for 6.3% of 5 s samples recorded from NICU A and 2.8% of NICU B samples. Twenty-four h periodicities in sound levels as a function of regular staff activities were apparent, but short-term variability was considerable.

Teamwork behaviours and errors during neonatal resuscitation

Objective To describe relationships between teamwork behaviours and errors during neonatal resuscitation. Methods Trained observers viewed video recordings of neonatal resuscitations (n = 12) for the occurrence of teamwork behaviours and errors. Teamwork state behaviours (such as vigilance and workload management, which extend for some duration) were assessed as the percentage of each resuscitation that the behaviour was observed and correlated with the percentage of observed errors. Teamwork event behaviours (such as information sharing, inquiry and assertion, which occur at specific times) were counted in 20-s intervals before and after resuscitation steps, and a generalised linear mixed model was calculated to evaluate relationships between these behaviours and errors. Results Resuscitation teams who were more vigilant committed fewer errors (Spearmans ρ for vigilance and errors = −0.62, 95% CI −0.07 to −0.87, p = 0.031). Assertions were more likely to occur before errors than correct steps (OR = 1.44, 95% CI 1.10 to 1.89, p = 0.008) and teaching/advising occurred less frequently after errors (OR = 0.59, 95% CI 0.37 to 0.94, p = 0.028). Though not statistically significant, there was less information sharing before errors (OR = 0.90, 95% CI 0.77 to 1.05, p = 0.172). Conclusions Vigilance is an important behaviour for error management. Assertion may have caused errors, or perhaps was an indicator for some other factor that caused errors. Teams may have preferred to resolve errors directly, rather than using errors as opportunities to teach their teammates. These observations raise important questions about the appropriate use of some teamwork behaviours and how to include them in team training programmes.

Changes in the PQRST Intervals and Heart Rate Variability Associated with Rewarming in Two Newborns Undergoing Hypothermia Therapy

Background: Little is known about the effects of hypothermia therapy and subsequent rewarming on the PQRST intervals and heart rate variability (HRV) in term newborns with hypoxic-ischemic encephalopathy (HIE). Objectives: This study describes the changes in the PQRST intervals and HRV during rewarming to normal core body temperature of 2 newborns with HIE after hypothermia therapy. Methods: Within 6 h after birth, 2 newborns with HIE were cooled to a core body temperature of 33.5°C for 72 h using a cooling blanket, followed by gradual rewarming (0.5°C per hour) until the body temperature reached 36.5°C. Custom instrumentation recorded the electrocardiogram from the leads used for clinical monitoring of vital signs. Generalized linear mixed models were calculated to estimate temperature-related changes in PQRST intervals and HRV. Results: For every 1°C increase in body temperature, the heart rate increased by 9.2 bpm (95% CI 6.8–11.6), the QTc interval decreased by 21.6 ms (95% CI 17.3–25.9), and low and high frequency HRV decreased by 0.480 dB (95% CI 0.052–0.907) and 0.938 dB (95% CI 0.460–1.416), respectively. Conclusions: Hypothermia-induced changes in the electrocardiogram should be monitored carefully in future studies.

Heart rate variability in response to pain stimulus in VLBW infants followed longitudinally during NICU stay

The objective of this longitudinal study, conducted in a neonatal intensive care unit, was to characterize the response to pain of high-risk very low birth weight infants (<1,500 g) from 23 to 38 weeks post-menstrual age (PMA) by measuring heart rate variability (HRV). Heart period data were recorded before, during, and after a heel lanced or wrist venipunctured blood draw for routine clinical evaluation. Pain response to the blood draw procedure and age-related changes of HRV in low-frequency and high-frequency bands were modeled with linear mixed-effects models. HRV in both bands decreased during pain, followed by a recovery to near-baseline levels. Venipuncture and mechanical ventilation were factors that attenuated the HRV response to pain. HRV at the baseline increased with post-menstrual age but the growth rate of high-frequency power was reduced in mechanically ventilated infants. There was some evidence that low-frequency HRV response to pain improved with advancing PMA.

A comparison of fetal and neonatal heart rate variability at similar post-menstrual ages

Substantial differences of heart rate variability (HRV) were found between fetuses and prematurely born neonates in the high-frequency band of the power spectrum. The range of post-menstrual ages of the fetuses and neonates were closely matched in this study. Growth of HRV was observed in low-frequency and high-frequency bands, reflecting maturation of the autonomic nervous system. The higher level of fetal HRV in the high-frequency band persisted even after accounting for age-related changes. Multiscale entropy was also higher in fetuses than in prematurely born neonates. These results suggest that the autonomic balance is poorer among neonates born prematurely than in fetuses of identical post-menstrual age.

Effects of Hypoxic-Ischemic Encephalopathy and Whole-Body Hypothermia on Neonatal Auditory Function: A Pilot Study

We assessed the effects of hypoxic-ischemic encephalopathy (HIE) and whole-body hypothermia therapy on auditory brain stem evoked responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). We performed serial assessments of ABRs and DPOAEs in newborns with moderate or severe HIE, randomized to hypothermia ( N = 4) or usual care ( N = 5). Participants were five boys and four girls with mean gestational age (standard deviation) of 38.9 (1.8) weeks. During the first week of life, peripheral auditory function, as measured by the DPOAEs, was disrupted in all nine subjects. ABRs were delayed but central transmission was intact, suggesting a peripheral rather than a central neural insult. By 3 weeks of age, peripheral auditory function normalized. Hypothermia temporarily prolonged the ABR, more so for waves generated higher in the brain stem but the effects reversed quickly on rewarming. Neonatal audiometric testing is feasible, noninvasive, and capable of enhancing our understanding of the effects of HIE and hypothermia on auditory function.

Noise in neonatal intensive care units (NICUs) and its effect on high risk newborns

We conducted sound surveys in a large state of the art NICU with six separate rooms devoted to the sickest babies requiring the most intensive care (Level III) and six rooms devoted to babies requiring special but less intensive care (Level II). Each room was capable of caring for up to 8 babies. Additionally, there were 8 individual Isolation rooms. We used Larson Davis Spark■ 703+ dosimeters to record 21 week long sound surveys, seven in each type of room. The American Academy of Pediatrics (1997) has recommended that sound levels in NICUs should never exceed 45 dB(A). That recommendation was exceeded 73.6% of the time in Level II, 92.1% of the time in Isolation, and 96.6% of the time in Level III. Sound levels were lowest in the Level II rooms especially for the softest sounds recorded (L90 and L70). Level III rooms were noisiest except for the noisiest decile of sound (L10). Isolation rooms were noisiest at the highest sound levels (probably because of their reverberant construction materials and encl...

Spectral analysis of time series of events: effect of respiration on heart rate in neonates

Certain types of biomedical processes such as the heart rate generator can be considered as signals that are sampled by the occurring events, i.e. QRS complexes. This sampling property generates problems for the evaluation of spectral parameters of such signals. First, the irregular occurrence of heart beats creates an unevenly sampled data set which must either be pre-processed (e.g. by using trace binning or interpolation) prior to spectral analysis, or analyzed with specialized methods (e.g. Lombs algorithm). Second, the average occurrence of events determines the Nyquist limit for the sampled time series. Here we evaluate different types of spectral analysis of recordings of neonatal heart rate. Coupling between respiration and heart rate and the detection of heart rate itself are emphasized. We examine both standard and data adaptive frequency bands of heart rate signals generated by models of coupled oscillators and recorded data sets from neonates. We find that an important spectral artifact occurs due to a mirror effect around the Nyquist limit of half the average heart rate. Further we conclude that the presence of respiratory coupling can only be detected under low noise conditions and if a data-adaptive respiratory band is used.