Early life exposure of infants to benzylpenicillin and gentamicin is associated with a persistent amplification of the gut resistome.

BACKGROUND: Infant gut microbiota is highly malleable, but the long-term longitudinal impact of antibiotic exposure in early life, together with the mode of delivery on infant gut microbiota and resistome, is not extensively studied. METHODS: Two hundred and eight samples from 45 infants collected from birth until 2 years of age over five time points (week 1, 4, 8, 24, year 2) were analysed. Based on shotgun metagenomics, the gut microbial composition and resistome profile were compared in the early life of infants divided into three groups: vaginal delivery/no-antibiotic in the first 4 days of life, C-section/no-antibiotic in the first 4 days of life, and C-section/antibiotic exposed in first 4 days of life. Gentamycin and benzylpenicillin were the most commonly administered antibiotics during this cohort's first week of life. RESULTS: Newborn gut microbial composition differed in all three groups, with higher diversity and stable composition seen at 2 years of age, compared to week 1. An increase in microbial diversity from week 1 to week 4 only in the C-section/antibiotic-exposed group reflects the effect of antibiotic use in the first 4 days of life, with a gradual increase thereafter. Overall, a relative abundance of Actinobacteria and Bacteroides was significantly higher in vaginal delivery/no-antibiotic while Proteobacteria was higher in C-section/antibiotic-exposed infants. Strains from species belonging to Bifidobacterium and Bacteroidetes were generally persistent colonisers, with Bifidobacterium breve and Bifidobacterium bifidum species being the major persistent colonisers in all three groups. Bacteroides persistence was dominant in the vaginal delivery/no-antibiotic group, with species Bacteroides ovatus and Phocaeicola vulgatus found to be persistent colonisers in the no-antibiotic groups. Most strains carrying antibiotic-resistance genes belonged to phyla Proteobacteria and Firmicutes, with the C-section/antibiotic-exposed group presenting a higher frequency of antibiotic-resistance genes (ARGs). CONCLUSION: These data show that antibiotic exposure has an immediate and persistent effect on the gut microbiome in early life. As such, the two antibiotics used in the study selected for strains (mainly Proteobacteria) which were multiple drug-resistant (MDR), presumably a reflection of their evolutionary lineage of historical exposures-leading to what can be an extensive and diverse resistome. Video Abstract.

Evaluating the use of statistical and machine learning methods for estimating breed composition of purebred and crossbred animals in thirteen cattle breeds using genomic information.

Introduction: The ability to accurately predict breed composition using genomic information has many potential uses including increasing the accuracy of genetic evaluations, optimising mating plans and as a parameter for genotype quality control. The objective of the present study was to use a database of genotyped purebred and crossbred cattle to compare breed composition predictions using a freely available software, Admixture, with those from a single nucleotide polymorphism Best Linear Unbiased Prediction (SNP-BLUP) approach; a supplementary objective was to determine the accuracy and general robustness of low-density genotype panels for predicting breed composition. Methods: All animals had genotype information on 49,213 autosomal single nucleotide polymorphism (SNPs). Thirteen breeds were included in the analysis and 500 purebred animals per breed were used to establish the breed training populations. Accuracy of breed composition prediction was determined using a separate validation population of 3,146 verified purebred and 4,330 two and three-way crossbred cattle. Results: When all 49,213 autosomal SNPs were used for breed prediction, a minimal absolute mean difference of 0.04 between Admixture vs. SNP-BLUP breed predictions was evident. For crossbreds, the average absolute difference in breed prediction estimates generated using SNP-BLUP and Admixture was 0.068 with a root mean square error of 0.08. Breed predictions from low-density SNP panels were generated using both SNP-BLUP and Admixture and compared to breed prediction estimates using all 49,213 SNPs (representing the gold standard). Breed composition estimates of crossbreds required more SNPs than predicting the breed composition of purebreds. SNP-BLUP required ≥3,000 SNPs to predict crossbred breed composition, but only 2,000 SNPs were required to predict purebred breed status. The absolute mean (standard deviation) difference across all panels <2,000 SNPs was 0.091 (0.054) and 0.315 (0.316) when predicting the breed composition of all animals using Admixture and SNP-BLUP, respectively compared to the gold standard prediction. Discussion: Nevertheless, a negligible absolute mean (standard deviation) difference of 0.009 (0.123) in breed prediction existed between SNP-BLUP and Admixture once ≥3,000 SNPs were considered, indicating that the prediction of breed composition could be readily integrated into SNP-BLUP pipelines used for genomic evaluations thereby avoiding the necessity for a stand-alone software.

Exploring Localized Muscle Fatigue Responses at Current Upper-Extremity Ergonomics Threshold Limit Values.

OBJECTIVE: The purpose of this study was to evaluate localized muscle fatigue responses at three upper-extremity ergonomics threshold limit value (TLV) duty cycles. BACKGROUND: Recently, a TLV equation was published to help mitigate excessive development of localized muscle fatigue in repetitive upper limb tasks. This equation predicts acceptable levels of maximal voluntary contraction (% MVC) for a given duty cycle (DC). Experimental validation of this TLV curve has not yet been reported, which can help guide utilization by practitioners. METHOD: Eighteen participants performed intermittent isometric elbow flexion efforts, in three separate counter-balanced sessions, at workloads defined by the American Conference of Governmental Industrial Hygenists' (ACGIH) TLV equation: low DC (20% DC, 29.6% MVC), medium DC (40% DC, 19.7% MVC), and high DC (60% DC, 13.9% MVC). Targeted localized muscle fatigue (LMF) of the biceps brachii was tracked across numerous response variables, including decline in strength (MVC), electromyography (EMG) amplitude and mean power frequency (MnPF), and several psychophysical ratings. RESULTS: At task completion, biceps MnPF and MVC (strength) were significantly different between each TLV workload, with the high DC condition eliciting the largest declines in MnPF and MVC. CONCLUSION: Findings demonstrate that working at different DCs along the ACGIH TLV curve may not be equivalent in preventing excessive LMF. Higher DC workloads elicited a greater LMF response across several response variables. APPLICATION: High DC work of the upper extremity should be avoided to mitigate excess LMF development. Current TLVs for repetitive upper-extremity work may overestimate acceptable relative contraction thresholds, particularly at higher duty cycles.

Nine Degree-of-Freedom Kinematic Modeling of the Upper-Limb Complex for Constrained Workspace Evaluation.

The design of rehabilitation devices for patients experiencing musculoskeletal disorders (MSDs) requires a great deal of attention. This article aims to develop a comprehensive model of the upper-limb complex to guide the design of robotic rehabilitation devices that prioritize patient safety, while targeting effective rehabilitative treatment. A 9 degree-of-freedom kinematic model of the upper-limb complex is derived to assess the workspace of a constrained arm as an evaluation method of such devices. Through a novel differential inverse kinematic method accounting for constraints on all joints1820, the model determines the workspaces in which a patient is able to perform rehabilitative tasks and those regions where the patient needs assistance due to joint range limitations resulting from an MSD. Constraints are imposed on each joint by mapping the joint angles to saturation functions, whose joint-space derivative near the physical limitation angles approaches zero. The model Jacobian is reevaluated based on the nonlinearly mapped joint angles, providing a means of compensating for redundancy while guaranteeing feasible inverse kinematic solutions. The method is validated in three scenarios with different constraints on the elbow and palm orientations. By measuring the lengths of arm segments and the range of motion for each joint, the total workspace of a patient experiencing an upper-limb MSD can be compared to a preinjured state. This method determines the locations in which a rehabilitation device must provide assistance to facilitate movement within reachable space that is limited by any joint restrictions resulting from MSDs.

A biomechanical evaluation of different footrest heights during standing computer work.

Working at a standing desk is a popular strategy to help reduce low back pain development during prolonged computer work. The purpose of this study was to examine how muscle activity, joint kinematics, weight distribution, balance and low back discomfort were affected by utilising footrests at different heights while working at a standing desk. Sixteen individuals performed a computer task at a standing workstation under four conditions: flat ground stance, and standing with one leg elevated on a low (10 cm), medium (20 cm), or high (30 cm) footrest. Footrest usage altered lumbo-pelvic and bilateral hip joint angles, muscle activity, weight distribution, and range of sway in the elevated limb. Additionally, footrest height altered lumbo-pelvic and hip joint position in the elevated limb. Discomfort increased with time across all conditions. Results suggest that intermittent utilisation of a footrest should be considered to promote changes in posture and muscle activity during prolonged computer use. Practitioner summary: This laboratory study showed that utilising a footrest between the heights of 10-30 cm during standing computer work may be beneficial to promote changes in posture and muscle activity over time. However, we recommend exercising caution while maintaining any standing position beyond 10 min of consecutive use. Abbreviations: LBP: low back pain; PD: pain developer; NPD: non-pain developer; GMe: gluteus medius; TFL: tensor fascia lata; LES: lumbar erector spinae; COP: centre of pressure; NDI: northern digital incorporated; CV: coefficient of variation; WHQ: waterloo handedness questionnaire; WFQ: waterloo footedness questionnaire; VAS: visual analogue scale; OBDI: Oswestry back disability index; IBS: International Society of Biomechanics; sEMG: surface electromyography; MVIC: maximum voluntary isometric contraction; RMS: root mean square; A/P: anterior/posterior; M/L: medial/lateral; % MVE: percentage of maximum voluntary excitation; ROM: range of motion; MCID: minimum clinically important difference.

Disrupting prolonged sitting reduces IL-8 and lower leg swell in active young adults.

BACKGROUND: Evidence suggests that disrupting prolonged bouts of sitting with short bouts of physical activity can significantly reduce blood glucose and improve insulin sensitivity; however, limited research is available on the impact of such disruptions on inflammation and swelling. The purpose of this study was to determine whether short bouts of exercise performed each hour during a 4 h sitting session were able to negate the effects of prolonged sitting (PS) on several cardiometabolic outcomes. METHODS: Eligible participants (n = 10) attended two laboratory sessions: PS (uninterrupted sitting for 4 h) and disrupted sitting (DS; 4 h sitting session disrupted by 3 min of exercise each hour (60-s warm-up at 50 W, 5 s of unloaded cycling, 20-s sprint at 5% body weight, and 95-s cool-down at 50 W)). The exercise bouts were performed at minute 60, 120, and 180. Blood and saliva samples, and measures of heart rate and blood pressure were assessed before (T1) and after (T2) each session; leg swell was measured continuously. RESULTS: Concentrations of salivary IL-8 increased during PS (T1: 0.19 ± 0.32; T2: 0.50 ± 1.00 pg/µg of protein) but decreased during DS (T1: 0.41 ± 0.23; T2: 0.22 ± 0.11 pg/µg of protein, d: 0.51, p = 0.002). Leg swell increased and plateaued in PS, but was attenuated during DS. CONCLUSION: It appears that short bouts of exercise significantly reduce swelling in the lower leg and IL-8 levels in the saliva, indicating that even among healthy, active, young adults, disrupting prolonged sitting can significantly reduce swelling and systemic inflammation.

Estimates of persistent inward current in human motor neurons during postural sway.

Persistent inward current (PIC) plays a critical role in setting the gain of spinal motor neurons. In humans, most estimates of PIC are made from plantarflexor or dorsiflexor motor units in a seated position. This seated and static posture negates the task-dependent nature of the monoaminergic drive and afferent inhibition that modulate PIC activation. Our purpose was to estimate PIC during both the conventional seated posture and in a more functionally relevant anterior postural sway. We hypothesized that paired motor unit estimates of PIC would be greater when during standing compared with sitting. Soleus motor neuron PIC was estimated via the paired motor unit (PMU) technique. For each motor unit pair, difference in reference unit firing frequency (ΔF) estimates of PIC were made during isometric ramps in plantarflexion force during sitting (conventional approach) and during standing anterior postural sway (new approach). Baseline reciprocal inhibition (RI) was also measured in each posture using the poststimulus time histogram technique. ΔF estimates during standing postural sway were not different [2.64 ± 0.95 pulses/s (pps), P = 0.098] from seated PIC estimates (3.15 ± 1.45 pps) measured from the same motor unit pair. Similarly, reciprocal inhibition at the onset of each task was the same in standing (-0.60 ± 0.32, P = 0.301) and seated (-0.86 ± 0.82) postures. PMU recordings made during standing postural sway met all assumptions that underlay the PMU technique, including rate modulation ≥0.5 pps (3.11 ± 1.90 pps), rate-rate correlation r ≥ 0.7 (0.84 ± 0.13), and time between reference and test unit recruitment ≥1 s (1.83 ± 0.81 s). This study presents a novel, functionally relevant standing method for investigating PIC in humans.NEW & NOTEWORTHY Paired motor unit (PMU) estimates of persistent inward current (PIC) in human soleus motor units are typically made in seated posture. Our study demonstrates that these estimates can be made during standing forward sway, a task that more accurately reflects the postural role of human soleus muscle. PMU recordings made during standing postural sway were validated using all previously published criteria used to test the assumptions of the PMU technique. Standing estimates of PIC did not differ from seated estimates made from the same motor unit pairs.

A cryogenic spin-torque memory element with precessional magnetization dynamics.

We present a study of precessional magnetization switching in orthogonal spin-torque spin-valve devices at low temperatures. The samples consist of a spin-polarizing layer that is magnetized out-of-the film plane and an in-plane magnetized free and reference magnetic layer separated by non-magnetic metallic layers. We find coherent oscillations in the switching probability, characterized by high speed switching (~200 ps), error rates as low as 10-5 and decoherence effects at longer timescales (~1 ns). Our study, which is conducted over a wide range of parameter space (pulse amplitude and duration) with deep statistics, demonstrates that the switching dynamics are likely dominated by the action of the out-of-plane spin polarization, in contrast to in-plane spin-torque from the reference layer, as has been the case in most previous studies. Our results demonstrate that precessional spin-torque devices are well suited to a cryogenic environment, while at room temperature they have so far not exhibited coherent or reliable switching.

Parental And Clinician Views Of Consent In Neonatal Research.

AIM: To determine parental and clinician views of the informed consent process in neonatal research. METHODS: A questionnaire-based study on the informed consent process. Two questionnaires were developed and distributed to parents and clinicians over a four-month period. RESULTS: Thirty-four parents (79%) surveyed had consented their baby to a research study. The majority of clinicians (72%) had a preference for antenatal provision of information. A desire to help future babies (97%, n=32) and a belief that their baby's healthcare would directly benefit (72%, n=28) were primary reasons for consenting. The majority (76% n=28) of parents were not in favour of a waiver of consent. However twenty clinicians (56%) agreed that a waiver of consent may be appropriate in neonatal research. Thirty-one (86%) clinicians rated GCP training as important. DISCUSSION: Parents are generally supportive of neonatal research. Good clinical practice training is essential for clinicians involved in neonatal research.

The intestinal protist Blastocystis is not a common member of the healthy infant gut microbiota in a Westernized country (Ireland).

Research into the gut microbiota of human infants is necessary in order to better understand how inter-species interactions and ecological succession shape the diversity of the gut microbiota, and in turn, how the specific composition of the gut microbiota impacts on host health both during infancy and in later years. Blastocystis is a ubiquitous intestinal protist that has been linked to a number of intestinal and extra-intestinal diseases. However, emerging data show that asymptomatic carriage is common and that Blastocystis is prevalent in the healthy adult gut microbiota. Nonetheless, little is known about the prevalence and diversity of this microorganism in the healthy infant gut, including when and how individuals become colonized by Blastocystis. Here, we surveyed the prevalence and diversity of Blastocystis in an infant population (n = 59) from an industrialized country (Ireland) using Blastocystis-specific primers at three or more time-points up to 24 months old. Only three infants were positive for Blastocystis (prevalence = 5%) and this was only noted for samples collected at month 24. This rate is comparatively low relative to previously reported prevalence rates in the contemporaneous adult population. These data suggest that infants in Westernized countries that are successfully colonized by Blastocystis most likely acquire this microorganism via horizontal transfer.

Monitoring cerebral oxygenation of preterm infants using a neonatal specific sensor.

INTRODUCTION: Cerebral oxygenation (rcSO2) monitoring in preterm infants may identify periods of cerebral hypoxia or hyperoxia. We hypothesised that there was a relationship between rcSO2 values and short term outcome in infants of GA < 32weeks. METHODS: RcSO2 values were recorded for the first 48 h of life using an INVOS monitor with a neonatal sensor. The association between cranial ultrasound scan measured brain injury and rcSO2 was assessed. RESULTS: 120 infants were included. Sixty-nine percent (83) of infants had a normal outcome (no IVH, no PVL, and survival at 1 month); less than one-quarter, 22% (26), had low grade IVH 1 or 2 (moderate outcome); and 9% (11) of infants had a severe outcome (IVH ≥ 3, PVL or died before 1 month age). rcSO2 values were lower for infants GA < 28weeks when compared with those GA 28-32, p < 0.001. There was no difference in absolute rcSO2 values between the three outcome groups but a greater degree of cerebral hypoxia was associated with preterm infants who had low grade 1 or 2 IVH. CONCLUSION: Infants of GA < 28 weeks have lower cerebral oxygenation in the first 2 days of life. A greater degree of hypoxia was seen in infants with grade 1 or 2 haemorrhage. Normative ranges need to be gestation specific.

Effects of therapeutic hypothermia on the gut microbiota and metabolome of infants suffering hypoxic-ischemic encephalopathy at birth.

Neonatal hypoxic ischemic encephalopathy (HIE) in the perinatal period can lead to significant neurological deficits in later life. Total body cooling (TBC) is a neuroprotective strategy used in the treatment of HIE and has been shown to reduce seizures and improve neurodevelopmental outcomes in treated infants. Little is known, however, about the effects of HIE/TBC on the developing gut microbiota composition and subsequent metabolic profile. Ten term infants with HIE who received TBC at 33.5°C for 72h were recruited. A control group consisted of nine healthy full term infants. Faecal samples were collected from both groups at 2 years of age and stored at -20°C. 16S rRNA amplicon Illumina sequencing was carried out to determine gut microbiota composition and 1H NMR analysis was performed to determine the metabolic profile of faecal water. The gut microbiota composition of the HIE/TBC infants were found to have significantly lower proportions of Bacteroides compared to the non-cooled healthy control group. Alpha diversity measures detected significantly lower diversity in microbial richness in the HIE/TBC infant group compared to the control infants (Shannon index, <0.05). High inter-individual variation was found in gut microbiota composition and metabolic profile of both groups. Initial principal coordinate analysis and hierarchal clustering of compounds on MetaboAnalyst 3.0 indicated no clear separation in the metabolic profile of these two infant groups. These results suggest that there is no significant impact on the gut microbial development of HIE/TBC infants compared to healthy infants at 2years of life. To our knowledge this is the first study to report the gut microbiota composition and metabolic profile of infants who have experienced HIE/TBC at birth.

Consent for routine neonatal procedures: A study of practices in Irish neonatal units. How do we compare with the gold standard BAPM guidelines?

The Irish National Consent Policy (NCP) proposes that the legal requirement for consent extends to all forms of interventions, investigations and treatment, carried out on or behalf of the Health Service Executive (HSE). This study employs a quantitative descriptive approach to investigate the practices for obtaining consent for an identified group of routine neonatal procedures in neonatal facilities throughout Ireland. The BAPM (British Association of Perinatal Medicine) guidelines were identified as 'gold standard' for the purposes of this study. The results indicated a lack of consistency between participating units pertaining to the modes of consent utilised and notable variances from 'gold standard' guidelines. Unanimity was evident for 3 procedures only (administering BCG, 6-in-1, and donor breast milk to infant). Significant findings related to EEG with video recordings, MRI/CT and gastro intestinal imaging, screening of an infant with suspected substance abuse or retinopathy of prematurity screening (ROP), administration of Vitamin K, and the carrying out of a lumbar puncture.

EFFECTS OF A BAND LOOP ON LOWER EXTREMITY MUSCLE ACTIVITY AND KINEMATICS DURING THE BARBELL SQUAT.

BACKGROUND: Medial knee collapse can signal an underlying movement issue that, if uncorrected, can lead to a variety of knee injuries. Placing a band around the distal thigh may act as a proprioceptive aid to minimize medial collapse of the knee during squats; however, little is known about EMG and biomechanics in trained and untrained individuals during the squat with an elastic band added. HYPOTHESIS/PURPOSE: To investigate the effects of the TheraBand® Band Loop on kinematics and muscle activity of the lower extremity during a standard barbell back squat at different intensities in both trained and untrained individuals. STUDY DESIGN: Cross-sectional, repeated measures. METHODS: Sixteen healthy, male, university aged-participants were split into two groups of eight, consisting of a trained and untrained group. Participants performed both a 3-repetition maximum (3-RM) and a bodyweight load squat for repetitions to failure. Lower extremity kinematics and surface electromyography of four muscles were measured bilaterally over two sessions, an unaided squat and a band session (band loop placed around distal thighs). Medial knee collapse, measured as a knee width index, and maximum muscle activity were calculated. RESULTS: During the 3-RM, squat weight was unaffected by band loop intervention (p = 0.486) and the trained group lifted more weight than the untrained group (p<0.007). The trained group had a greater squat depth for both squat conditions, regardless of the band (p = 0.0043). Knee width index was not affected by the band during the eccentric phase of bodyweight squats in the trained (band: 0.76 ± 0.08, no band: 0.73 ± 0.08) or untrained group (band: 0.77 ± 0.70, no band: 0.75 ± 0.13) (p = 0.670). During the concentric phase, knee width index was significantly lower for 3-RM squats, regardless of group. CONCLUSION: Despite minimal changes in kinematics for the untrained group, increased muscle activity with the band loop may suggest that a training aid may, over time, lead to an increase in barbell squat strength by increasing activation of agonist muscles more than traditional, un-banded squats. Greater maximal muscle activity in most muscles during band loop sessions may provide enhanced knee stability via increased activation of stabilizing muscles. LEVEL OF EVIDENCE: 3.

Emergency uncross-matched blood transfusions in a tertiary neonatal unit.

AIM: To determine the neonatal incidence, indications and outcomes following transfusions with emergency uncross-matched O-negative blood. METHODS: A five-year retrospective review in a single tertiary neonatal unit was conducted. The blood transfusion laboratory's database was analysed for all infants who had received an emergency released blood transfusion (ERBT) between January 2010 and December 2014. RESULTS: We calculated a total ERBT rate of 0.91 per 1000 live births (39/42 657) and a rate of 0.43 per 1000 in infants >34 weeks' gestation (18/41 637). A rate of 0.14 per 1000 births (6/42 657) received an ERBT as part of newborn stabilisation despite almost half of our infant cohort having intrapartum haemorrhages (n = 18, 46%). One-third (13/39) of all infants who were transfused died. Outcome varied depending on underlying aetiology, gestation and birthweight. The highest mortality was in preterm infants weighing <1000 g, of whom 70% died. CONCLUSION: This study establishes an ERBT rate of <1 per 1000 births, and 0.14 per 1000 infants received an ERBT as part of newborn delivery room stabilisation. ERBTs are associated with a high mortality rate. This study highlights the need for further research and guidelines that clarify the role of ERBTs in newborn stabilisations.

Reporting on data monitoring committees in neonatal randomised controlled trials is inconsistent.

AIM: To evaluate the reported use of data monitoring committees (DMCs), the frequency of interim analysis, prespecified stopping rules and early trial termination in neonatal randomised controlled trials (RCTs). METHODS: We reviewed neonatal RCTs published in four high-impact general medical journals, specifically looking at safety issues including documented involvement of a DMC, stated interim analysis, stopping rules and early trial termination. We searched all journal issues over an 11-year period (2003-2013) and recorded predefined parameters on each item for RCTs meeting inclusion criteria. RESULTS: Seventy neonatal trials were identified in four general medical journals: Lancet, New England Journal of Medicine (NEJM), British Medical Journal and Journal of American Medical Association. A total of 43 (61.4%) studies reported the presence of a DMC, 36 (51.4%) explicitly mentioned interim analysis, stopping rules were reported in 15 (21.4%) RCTs and seven (10%) trials were terminated early. The NEJM most frequently reported these parameters compared to the other three journals reviewed. CONCLUSION: While the majority of neonatal RCTs report on DMC involvement and interim analysis, there is still scope for improvement. Clear documentation of safety-related issues should be a central component of reporting in neonatal trials involving newborn infants.

Auscultate, palpate and tap: time to re-evaluate.

AIM: To determine the accuracy of current methods of heart rate (HR) assessment. METHODS: All participants palpated a simulated pulsating umbilicus (UMB), listened to a tapping rate (TAP) and auscultated a simulated HR (AUSC). A simulated HR of 54, 88 and 128 beats per minute (bpm) was randomised for all methods. RESULTS: Twenty-nine healthcare staff participated in this study. Correct assessment of HR of 54 bpm as being within the 0-59 range occurred in 17.2% UMB, 17.2% TAP and 31% AUSC and was obtained in <10 seconds by 48.3%, 65.5% and 62.1%, respectively. A rate of 88 bpm was correctly assessed as within the 60-100 range in 82.8% UMB, 79.3% TAP and 79.3% AUSC and was obtained in <10 seconds by 55.2%, 58.6% and 55.2%, respectively. A rate of 128 bpm was identified as >100 bpm by 96.6% UMB, 93.1% TAP, and 93.1% AUSC and was obtained in <10 seconds by 51.7%, 55.2% and 62.1%, respectively. CONCLUSION: Current methods in assessing rates below 60 bpm are inaccurate and may overestimate HR. We recommend that these methods alone should not be relied upon in neonatal resuscitation and objective assessment of heart rate should be readily available at all newborn resuscitations.

Perfusion index in the preterm infant immediately after birth.

AIM: To evaluate PI in preterm infants during the first 10 min of life. DESIGN/METHODS: An observational study was conducted in the delivery room on preterm infants (less than 32 week gestation). PI values were obtained from a pre ductal saturation probe placed on the right wrist. Analysis was performed on the first 10 min of data to investigate the correlation of PI with gestational age, heart rate, blood pressure, and lactate values. RESULTS: 33 infants with a median gestational age of 29 wks (IQR, 26-30 wks) and median birth weight of 1205 g (IQR, 925-1520 g) were included for analysis. The overall median PI value for the first 10 min was 1.3 (IQR, 0.86-1.68). There was no significant correlation found between delivery room PI and gestational age(r=0.28, 95% CI: -0.09, 0.59), lactate levels (r=-0.25, 95% CI: -0.62, 0.18) and blood pressure values (r=-0.18, 95% CI: -0.46, 0.20). An average correlation value of r=-0.417 (95% CI: - 0.531, -0.253) was found between PI and heart rate values. There was no statistical difference between the median of the median PI value over the first 5 min of life compared to the second 5 min (p=0.22). Variability, as quantified by the IQR, was higher in the first 5 min compared to the second 5 min: median of 0.5(IQR, 0.27, 0.92) vs 0.2(IQR, 0.10, 0.30) (p<0.00). CONCLUSIONS: Delivery room PI values are easily obtained, however, have significant variability over the first 5 min of life and may add little to delivery room assessment.