Chest Compression Technique Research Articles

СПОСОБЫ КОМПРЕССИИ ГРУДНОЙ КЛЕТКИ ПРИ МОДЕЛИРОВАНИИ РЕАНИМАЦИИ ПАЦИЕНТОВ С COVID-19: РАНДОМИЗИРОВАННОЕ ПЕРЕКРЕСТНОЕ ИМИТАЦИОННОЕ ИССЛЕДОВАНИЕ

Background: High-quality chest compression is one of the key elements of resuscitation to return of spontaneous circulation. In the COVID-19 era, medical personnel should wear personal protective equipment (PPE) against aerosol generating procedures (AGP) during resuscitation. However, the use of this personal protection equipment may reduce the effectiveness of medical procedures performed. Objective: We aimed to compare chest compression quality parameters between standard manual chest compression and chest compression with TrueCPR feedback device performed by medical students wearing full personal protractive equipment against aerosol generating procedure.Methods: The study was designed as a randomized, cross-over, single-blinded simulation study. Thirty-two medical students wearing PPE-AGP performed 2-min continuous chest compression on an adult simulator with and without TrueCPR feedback device.Results: Median chest compression depth with and without TrueCPR feedback device varied and amounted to 46 (IQR; 42-53) vs. 41 (IQR; 36-45) mm (MCC vs. TrueCPR, respectively). The manual chest compression rate was 117 (IQR; 112-125) compressions per minute (CPM) and was higher than with TrueCPR feedback device - 107 (IQR; 102-115; p = 0.017). Full chest relaxation in the manual's chest compression technique (without TrueCPR) was 33 (IQR; 26-42)% and was lower than with chest compression with TrueCPR feedback device - 58 (IQR; 40-75)% (p=0.002). Conclusions: We conclude that a TrueCPR feedback device improves chest compression quality during simulated COVID-19 resuscitation performed by medical students wearing PPE-AGP.

Straddle versus Conventional Chest Compressions in a Confined Space; a Comparative Study

Introduction:When cardiac arrest occurs in a confined space, such as in an aircraft or ambulance, kneeling by the patient’s side may be difficult. Straddle chest compression is an alternative technique that can be used in a confined space. This study was performed to compare the quality of chest compressions in straddle versus conventional CPR on a manikin model.Methods:The participants were randomized into two groups using the sequential numbered, opaque, sealed envelope method chosen through block-of-four randomization: straddle and conventional chest compression technique. Each participant performed a maximum of 4 minutes of hands-only chest compressions, and quality parameters (compression rate and depth) were recorded from the defibrillator's monitor.Results:124 participants with mean age of 26.67 ± 6.90 years (27.58% male) were studied. There was no difference in the mean compression rate between the conventional and straddle chest compression techniques (126.18 ± 17.11 and 127.01 ± 21.01 compressions/min, respectively; p = 0.811) or their mean compression depth (43.8 ± 9.60 and 43.4 ± 9.10 mm, respectively; p = 0.830). The participants’ comfort and fatigue were assessed through changes in their vital signs. In both methods, statistically significant differences were observed in vital signs before and after performing chest compression, but the differences were not clinically significant. In addition, there was no difference between the 2 groups in this regard.Conclusion:The quality of CPR using the straddle chest compression was as good as conventional chest compression technique. No significant differences were found in the quality of chest compressions or the participants’ comfort and fatigue levels.

Fetal Origins of Asthma: A Longitudinal Study from Birth to Age 36 Years.

Rationale: Deficits in infant lung function-including the ratio of the time to reach peak tidal expiratory flow to the total expiratory time (tptef/te) and maximal expiratory flow at FRC (V̇maxFRC)-have been linked to increased risk for childhood asthma.Objectives: To examine the individual and combined effects of tptef/te and V̇maxFRC in infancy on risk for asthma and abnormalities of airway structure into mid-adult life.Methods: One hundred eighty participants in the Tucson Children's Respiratory Study birth cohort had lung function measured by the chest-compression technique in infancy (mean age ± SD: 2.0 ± 1.2 mo). Active asthma was assessed in up to 12 questionnaires between ages 6 and 36 years. Spirometry and chest high-resolution computed tomographic (HRCT) imaging were completed in a subset of participants at age 26. The relations of infant tptef/te and V̇maxFRC to active asthma and airway structural abnormalities into adult life were tested in multivariable mixed models.Measurements and Main Results: After adjustment for covariates, a 1-SD decrease in infant tptef/te and V̇maxFRC was associated with a 70% (P = 0.001) and 55% (P = 0.005) increased risk of active asthma, respectively. These effects were partly independent, and two out of three infants who were in the lowest tertile for both tptef/te and V̇maxFRC developed active asthma by mid-adult life. Infant V̇maxFRC predicted reduced airflow and infant tptef/te reduced HRCT airway caliber at age 26.Conclusions: These findings underscore the long-lasting effects of the fetal origins of asthma, support independent contributions by infant tptef/te and V̇maxFRC to development of asthma, and link deficits at birth in tptef/te with HRCT-assessed structural airway abnormalities in adult life.

Which technique of chest compression should we use wearing full personal protective equipment: a pilot data

Which technique of chest compression should we use wearing full personal protective equipment: a pilot data

Analysis of Chest-Compression Depth and Full Recoil in Two Infant Chest-Compression Techniques Performed by a Single Rescuer: Systematic Review and Meta-Analysis.

Pediatric cardiac arrest is associated with high mortality and permanent neurological injury. We aimed to compare the effects of the two-thumb (TT) and two-finger (TF) techniques in infant cardiopulmonary resuscitation (CPR) performed by a single rescuer. We searched PubMed, EMBASE, and CENTRAL for randomized control trials published before December 2019. Studies comparing the TT and TF techniques in infant CPR were included for meta-analysis. Relevant information was extracted for methodological assessment. Twelve studies were included. The TT technique was associated with deeper chest-compression depth (mean difference: 4.71 mm; 95% confidence interval: 3.61 to 5.81; p < 0.001) compared with the TF technique. The TF technique was better in terms of the proportion of complete chest recoil (mean difference: −11.73%; 95% confidence interval: −20.29 to −3.17; p = 0.007). CPR was performed on a manikin model, and the application of the results to real human beings may be limited. The TT technique was superior to the TF technique in terms of chest-compression depth, but with inferior chest full recoil. Future investigations should focus on modifying the conventional TT technique to generate greater compression depth and achieve complete chest recoil.

Differences in the performance of resuscitation according to the resuscitation guideline terminology during infant cardiopulmonary resuscitation: "Approximately 4 cm" versus "at least one-third the anterior-posterior diameter of the chest".

This study was conducted to investigate the effect of resuscitation guideline terminology on the performance of infant cardiopulmonary resuscitation (CPR). A total of 40 intern or resident physicians conducted 2-min CPR with the two-finger technique (TFT) and two-thumb technique (TT) on a simulated infant cardiac arrest model with a 1-day interval. They were randomly assigned to Group A or B. The participants of Group A conducted CPR with the chest compression depth (CCD) target of "approximately 4 cm" and those of Group B conducted CPR with the CCD target of "at least one-third the anterior-posterior diameter of the chest". Single rescuer CPR was performed with a 15:2 compression to ventilation ratio on the floor. In both chest compression techniques, the average CCD of Group B was significantly deeper than that of Group A (TFT: 41.0 [range, 39.3-42.0] mm vs. 36.5 [34.0-37.9] mm, P = 0.002; TT: 42.0 [42.0-43.0] mm vs. 37.0 [35.3-38.0] mm, P < 0.001). Adequacy of CCD also showed similar results (Group B vs. A; TFT: 99% [82-100%] vs. 29% [12-58%], P = 0.001; TT: 100% [100-100%] vs. 28% [8-53%], P < 0.001). Using the CCD target of "at least one-third the anterior-posterior diameter of the chest" resulted in deep and adequate chest compressions during simulated infant CPR in contrast to the CCD target of "approximately 4 cm". Therefore, changes in the terminology used in the guidelines should be considered to improve the quality of CPR. Clinical Research Information Service; cris.nih.go.kr/cris/en (Registration number: KCT0003486).

Comparing the efficiency and convenience of one-rescuer cardiopulmonary resuscitation chest compression techniques for infants

Comparing the efficiency and convenience of one-rescuer cardiopulmonary resuscitation chest compression techniques for infants

Development and Evaluation of a New Chest Compression Technique for Cardiopulmonary Resuscitation in Infants.

We designed the newly developed flexed two-finger chest compression technique for cardiopulmonary resuscitation (CPR) in infants to increase the quality of chest compression by considering the advantages and disadvantages of the two-thumb encircling hand technique and conventional two-finger technique. The aim of the study is to compare the performance of the flexed two-finger technique and the currently used two-thumb technique or two-finger technique for infant CPR. A total of 42 doctors conducted 2-min single-rescuer CPR on a cardiac arrest infant model using the two-thumb technique followed, in a random order, by the two-finger technique and the flexed two-finger technique. Although the ratio of the adequate compression depth was highest in the two-thumb technique, followed by the flexed two-finger technique and two-finger technique (100% [98-100] vs. 99% [80-100] vs. 76% [42-95], respectively, P < 0.001), the hand-off time of the two-thumb technique was significantly longer than in the two-finger technique and flexed two-finger technique (31s [28-35] vs. 29s [27-32] vs. 29s [26-32], respectively, P < 0.001). The number of total chest compressions of the two-thumb technique was significantly lower than in the two-finger technique and flexed two-finger technique (150 [148-159] vs. 159 [149-173] vs. 162 [150-172], respectively, P < 0.001). The newly developed chest compression technique could provide adequate compression depth without increasing the hand-off time during single-rescuer infant CPR.Trial registration: Clinical Research Information Service, KCT0002730.

A new chest compression technique in infants

ObjectiveTo compare the quality of chest compressions performed according to the classical technique (MT) vs. a new technique (NM) (compression with 2 thumbs with closed fists) in an infant manikin. DesignA controlled, randomized cross-over study was carried out in professionals assisting pediatric patients. SettingA University Hospital with a Pediatric ICU in the north of Spain. ParticipantsResidents and nurses in Pediatrics who had completed a basic and an advanced pediatric cardiopulmonary resuscitation course. InterventionsQuantitative analysis of the variables referred to chest compression quality in a 2-min cardiopulmonary resuscitation scenario in infants. Laerdal's SimPad® with SkillReporter™ system was used. Main variables of interestMean rate and percentage of compressions in the recommended rate range, mean depth and percentage of compressions within the depth range of recommendations, percentage of compressions with adequate decompression, and percentage of compressions performed with the fingers in the center of the chest. ResultsGlobal quality of the compressions (NM: 84.2±23.7% vs. MT: 80.1±25.4% [P=.25; P=ns]), percentage of compressions with correct depth (NM: 59.9±35.8% vs. MT: 59.5±35.7% [P=.76; P=ns]), mean depth reached (NM: 37.3±3.8mm vs. MT: 36±5.3mm [P=.06; P=ns]), percentage of complete re-expansion of the chest (NM: 94.4±9.3% vs. MT: 92.4±18.3% [P=.58; P=ns]), and percentage of compressions with the recommended rate (NM: 62.2±34.6% vs. MT: 51±37.2% [P=.13; P=ns]) proved similar with both methods. ConclusionsThe quality of chest compressions with the new method (thumbs with closed fists) is similar to that afforded by the traditional method.

Comparison between modified and conventional one-handed chest compression techniques for child cardiopulmonary resuscitation: A randomised, non-blind, cross-over simulation trial.

Chest compression depth (CCD) decreases significantly when performing one-handed chest compression (OHCC). We modified OHCC posture to increase CCD as follows: first, the axis of the compression hand was adjusted to the compression area; second, the opposite hand was wrapped around the elbow of the compression arm. This study compared modified OHCC with conventional OHCC for child cardiopulmonary resuscitation. A total of 46 health-care providers performed 2 min of continuous chest compression using conventional OHCC (trial 1) and modified OHCC (trial 2) in a random order on a 5-year-old-sized child manikin lying on a bed. Chest compression parameters were assessed with an accelerometer and analysed by comparing the mean values of 30-s segments. The average CCD decreased significantly in all segments in both trials (trial 1 (segments 1-4): 40.9 ± 5.6 mm, 39.4 ± 6.6 mm, 38.0 ± 6.9 mm, 36.7 ± 7.3 mm, P < 0.001; trial 2 (segments 1-4): 42.3 ± 5.4 mm, 41.2 ± 6.2 mm, 40.1 ± 6.8 mm, 39.0 ± 6.9 mm, P < 0.001). However, the average CCD in trial 2 was significantly greater in all segments than that in trial 1 (segments 1-4: P = 0.016; P = 0.009; P = 0.004; P = 0.001). The average chest compression rates were comparable in all segments in both trials. By modifying OHCC posture, a deeper mean CCD could be maintained for 2 min than by using conventional OHCC.

Effect of metronome guidance on infant cardiopulmonary resuscitation.

This study was conducted to investigate the effect of metronome guidance on the performance of infant cardiopulmonary resuscitation (CPR). A total of 36 medical doctors conducted a 2-min single rescuer CPR with the two-finger technique (TFT) or two-thumb encircling hands technique (TT) on an infant manikin without metronome guidance (baseline test). After completing the baseline test, the participants were assigned to either a "guidance group" or "non-guidance group." The guidance group performed CPR with a high-pitched sound at 110 beats/min from a metronome (test 2), while the non-guidance group performed 2-min CPR without metronome guidance (test 1). Comparison between the results of tests 1 and 2 showed that the ratio of adequate chest compression rate was significantly different in both the TFT (73% [34-93] vs. 98% [95-99], P < 0.001) and the TT (53% [32-79] vs. 99% [98-100], P = 0.010). Other parameters including average depth and the ratio of adequate depth were not significantly different between tests 1 and 2 in both the TFT and TT.Conclusion: Metronome guidance improves the adequacy of chest compression rate during infant CPR without affecting chest compression depth in both the TFT and TT.Trial registration: Clinical Research Information Service, KCT0002735 What is Known: • The rate of chest compressions can be optimized by the use of metronome guidance in pediatric cardiopulmonary resuscitation (CPR). • An adverse effect of deteriorating chest compression depth was found while using a metronome guidance during adult CPR simulations. What is New: • The metronome guidance improved the adequacy of the chest compression rate during infant CPR without affecting other parameters including average depth and the ratio of adequate depth in both the two-finger chest compression technique and two-thumb encircling hand technique.

The SURV1VE trial\u2014sustained inflation and chest compression versus 3:1 chest compression-to-ventilation ratio during cardiopulmonary resuscitation of asphyxiated newborns: study protocol for a cluster randomized controlled trial

BackgroundThe need for cardiopulmonary resuscitation (CPR) is often unexpected, and the infrequent use of CPR in the delivery room (DR) limits the opportunity to perform rigorous clinical studies to determine the best method for delivering chest compression (CC) to newborn infants. The current neonatal resuscitation guidelines recommend using a coordinated 3:1 compression-to-ventilation (C:V) ratio (CC at a rate of 90/min and ventilations at a rate of 30/min). In comparison, providing CC during a sustained inflation (SI) (CC + SI) significantly improved hemodynamics, minute ventilation, and time to return of spontaneous circulation (ROSC) compared to 3:1 C:V ratio in asphyxiated piglets. Similarly, a small pilot trial in newborn infants showed similar results. Until now no study has examined different CC techniques during neonatal resuscitation in asphyxiated newborn infants in the DR. To date, no trial has been performed to directly compare CC + SI and 3:1 C:V ratio in the DR during CPR of asphyxiated newborn infants.MethodsThis is a large, international, multi-center, prospective, unblinded, cluster randomized controlled trial in asphyxiated newborn infants at birth. All term and preterm infants > 28+ 0 by best obstetrical estimate who require CPR at birth due to bradycardia (< 60/min) or asystole are eligible. The primary outcome of this study is to compare the time to ROSC in infants born > 28+ 0 weeks’ gestational age with bradycardia (< 60/min) or asystole immediately after birth who receive either CC + SI or 3:1 C:V ratio as the CPR strategy.DiscussionMorbidity and mortality rates are extremely high for newborns requiring CC. We believe the combination of simultaneous CC and SI during CPR has the potential to significantly improve ROSC and survival. In addition, we believe that CC + SI might improve respiratory and hemodynamic parameters and potentially minimize morbidity and mortality in newborn infants. In addition, this will be the first randomized controlled trial to examine CC in the newborn period.Trial registrationClinicalTrials.gov, NCT02858583. Registered on 8 August 2016

Confirming the Clinical Safety and Feasibility of a Bundled Methodology to Improve Cardiopulmonary Resuscitation Involving a Head-Up/Torso-Up Chest Compression Technique.

Objectives:Combined with devices that enhance venous return out of the brain and into the thorax, preclinical outcomes are improved significantly using a synergistic bundled approach involving mild elevation of the head and chest during cardiopulmonary resuscitation. The objective here was to confirm clinical safety/feasibility of this bundled approach including use of mechanical cardiopulmonary resuscitation provided at a head-up angle.Design:Quarterly tracking of the frequency of successful resuscitation before, during, and after the clinical introduction of a bundled head-up/torso-up cardiopulmonary resuscitation strategy.Setting:9-1-1 response system for a culturally diverse, geographically expansive, populous jurisdiction.Patients:All 2,322 consecutive out-of-hospital cardiac arrest cases (all presenting cardiac rhythms) were followed over 3.5 years (January 1, 2014, to June 30, 2017).Interventions:In 2014, 9-1-1 crews used LUCAS (Physio-Control Corporation, Redmond, WA) mechanical cardiopulmonary resuscitation and impedance threshold devices for out-of-hospital cardiac arrest. After April 2015, they also 1) applied oxygen but deferred positive pressure ventilation several minutes, 2) solidified a pit-crew approach for rapid LUCAS placement, and 3) subsequently placed the patient in a reverse Trendelenburg position (~20°).Measurements and Main Results:No problems were observed with head-up/torso-up positioning (n = 1,489), but resuscitation rates rose significantly during the transition period (April to June 2015) with an ensuing sustained doubling of those rates over the next 2 years (mean, 34.22%; range, 29.76–39.42%; n = 1,356 vs 17.87%; range, 14.81–20.13%, for 806 patients treated prior to the transition; p < 0.0001). Outcomes improved across all subgroups. Response intervals, clinical presentations and indications for attempting resuscitation remained unchanged. Resuscitation rates in 2015–2017 remained proportional to neurologically intact survival (~35–40%) wherever tracked.Conclusions:The head-up/torso-up cardiopulmonary resuscitation bundle was feasible and associated with an immediate, steady rise in resuscitation rates during implementation followed by a sustained doubling of the number of out-of-hospital cardiac arrest patients being resuscitated. These findings make a compelling case that this bundled technique will improve out-of-hospital cardiac arrest outcomes significantly in other clinical evaluations.

Which chest compression technique is more fatiguing for rescuer?

Which chest compression technique is more fatiguing for rescuer?

New infant chest compression technique. A prospective randomized crossover manikin trial

New infant chest compression technique. A prospective randomized crossover manikin trial

Comparison of two chest compression techniques during infant resuscitation. A randomized, cross-over study

Comparison of two chest compression techniques during infant resuscitation. A randomized, cross-over study

A Novel Method of Newborn Chest Compression: A Randomized Crossover Simulation Study.

Objective: To compare a novel two-thumb chest compression technique with standard techniques during newborn resuscitation performed by novice physicians in terms of median depth of chest compressions, degree of full chest recoil, and effective compression efficacy.Patients and Methods: The total of 74 novice physicians with less than 1-year work experience participated in the study. They performed chest compressions using three techniques: (A) The new two-thumb technique (nTTT). The novel method of chest compressions in an infant consists in using two thumbs directed at the angle of 90° to the chest while closing the fingers of both hands in a fist. (B) TFT. With this method, the rescuer compresses the sternum with the tips of two fingers. (C) TTHT. Two thumbs are placed over the lower third of the sternum, with the fingers encircling the torso and supporting the back.Results: The median depth of chest compressions for nTTT was 3.8 (IQR, 3.7–3.9) cm, for TFT−2.1 (IQR, 1.7–2.5) cm, while for TTHT−3.6 (IQR, 3.5–3.8) cm. There was a significant difference between nTTT and TFT, and TTHT and TFT (p < 0.001) for each time interval during resuscitation. The degree of full chest recoil was 93% (IQR, 91–97) for nTTT, 99% (IQR, 96–100) for TFT, and 90% (IQR, 74–91) for TTHT. There was a statistically significant difference in the degree of complete chest relaxation between nTTT and TFT (p < 0.001), between nTTT and TTHT (p = 0.016), and between TFT and TTHT (p < 0.001).Conclusion: The median chest compression depth for nTTT and TTHT is significantly higher than that for TFT. The degree of full chest recoil was highest for TFT, then for nTTT and TTHT. The effective compression efficiency with nTTT was higher than for TTHT and TFT. Our novel newborn chest compression method in this manikin study provided adequate chest compression depth and degree of full chest recoil, as well as very good effective compression efficiency. Further clinical studies are necessary to confirm these initial results.

USING CHEST COMPRESSIONS WITH ASYNCHRONOUS VENTILATION AT VARIOUS CHEST COMPRESSION RATES (90, 100, 120/MIN) – A RANDOMIZED CONTROLLED ANIMAL TRIAL

Abstract BACKGROUND The current Pediatric Advanced Life Support guidelines recommends that newborns who require cardiopulmonary resuscitation (CPR) in settings (e.g., prehospital, Emergency department, or paediatric intensive care unit, etc.) should receive continuous chest compressions with asynchronous ventilations (CCaV) if an advanced airway is in place. However, this has never been examined in a newborn model of neonatal asphyxia. OBJECTIVES To determine if CCaV at rates of 90/min or 120/min compared to current standard of 100/min will reduce the time to return of spontaneous circulation (ROSC) in a porcine model of neonatal resuscitation. DESIGN/METHODS Term newborn piglets were anesthetized, intubated, instrumented, and exposed to 40-min normocapnic hypoxia followed by asphyxia, which was achieved by clamping the endotracheal tube until asystole. Piglets were randomized into 3 CCaV groups: chest compression (CC) at a rate of 90/min (CCaV 90,n=7), of 100/min (CCaV 100,n=7), of 120/min (CCaV 120,n=7), or sham-operated group. A two-step randomization process with sequentially numbered, sealed brown envelope was used to reduce selection bias. After surgical instrumentation and stabilization an envelope containing the allocation “sham” or “intervention” was opened (step one). The sham-operated group had the same surgical protocol, stabilization, and equivalent experimental periods without hypoxia and asphyxia. Only piglets randomized to “intervention” underwent hypoxia and asphyxia. Once the criteria for CPR were met, a second envelope containing the group allocations was opened (step two). Cardiac function, carotid blood flow, cerebral oxygenation, and respiratory parameters were continuously recorded throughout the experiment. RESULTS The mean (±SD) duration of asphyxia was similar between the groups with 260 (±133)sec, 336 (±217)sec, and 231 (±174)sec for CCav 90, CCaV 100, and CCaV 120, respectively (p=1.000; oneway ANOVA with Bonferroni post-test). The mean (SD) time to ROSC was also similar between groups 342 (±345)sec, 312 (±316)sec, and 309 (±287)sec for CCav 90, CCaV 100, and CCaV 120, respectively (p=1.000; oneway ANOVA with Bonferroni post-test). Overall, 5/7 in the CCaV 90, 5/7 in CCaV 100, and 5/7 in the CCaV 120 survived. CONCLUSION There was no significant difference in time to ROSC for either chest compression technique during cardiopulmonary resuscitation in a porcine model of neonatal asphyxia.

USING DIFFERENT CHEST COMPRESSIONS AND VENTILATION RATIOS (2:1, 3:1, 4:1) DURING NEONATAL ASPHYXIA IN A PORCINE MODEL OF NEONATAL RESUSCITATION – A RANDOMIZED CONTROLLED ANIMAL TRIAL

Abstract BACKGROUND The rationale for a compression to ventilation ratio of 3:1 in neonates with primary hypoxic, hypercapnic cardiac arrest is to emphasize the importance of ventilation; however, there are no published studies testing this approach against alternative methods. OBJECTIVES To evaluate if using a 2:1 C:V ratio or a 4:1 C:V ratio will improve ROSC compared to using a 3:1 C:V ratio. DESIGN/METHODS Term newborn piglets were anesthetized, intubated, instrumented, and exposed to 40-min normocapnic hypoxia followed by asphyxia. Asphyxia was achieved by clamping the endotracheal tube until the piglet had asystole; at that time CPR was initiated. Piglets were then randomized into 3 groups: 2:1 C:V ratio (n=8), 3:1 ratio (n=8), 4:1 C:V ratio (n=8), or a sham operated group. A two-step randomization was used to reduce selection bias. After surgical instrumentation and stabilization, a sequentially numbered, sealed brown envelope containing the allocation “sham” or “intervention” was opened (step one). The sham-operated group had the same surgical protocol, stabilization, and equivalent experimental periods without hypoxia and asphyxia. Only piglets randomized to “intervention” underwent hypoxia and asphyxia. Once the criteria for CPR were met, a second envelope containing the allocations “2:1”,“3:1”,or “4:1”, was opened (step two). Cardiac function, carotid blood flow, cerebral oxygenation, and respiratory parameters were continuously recorded throughout the experiment. RESULTS The median (IQR) duration of asphyxia was similar between the groups with 318 (194–576)sec, 255 (226–334)sec, 233 (169–395)sec for 2:1, 3:1, 4:1 C:V, respectively (p=0.68; oneway ANOVA with Bonferroni). The median (IQR) time to ROSC was also similar between groups 127 (82–210)sec, 96 (88–126)sec, 119 (83–256)sec for 2:1, 3:1, 4:1 C:V, respectively (p=0.67; oneway ANOVA with Bonferroni). Overall, 8/8 in the 2:1 C:V ratio group, 7/8 in the 3:1 C:V ratio group, and 7/8 in the 4:1 C:V ratio group survived. CONCLUSION There was no significant difference in time to ROSC for either chest compression technique during cardiopulmonary resuscitation in a porcine model of neonatal asphyxia.

Pulmonary function in former very low birth weight preterm infants in the first year of life.

Pulmonary function in former preterm infants may be compromised during childhood. To assess pulmonary function in very-low-birth-weight preterm infants at 6-12 months of corrected age and analyze the factors associated with abnormal pulmonary function. Cross-sectional study with preterm infants at 6-12 months of corrected age with birth weight <1500 g. Children with malformations or affected by neuromuscular and respiratory diseases were excluded. Forced expiratory flows were assessed using the chest compression technique, and volumes were measured by total body plethysmography. Pulmonary function parameters in preterm infants were compared to a control group of same-aged children born at term. We studied 51 preterm and 37 infants born at term. Preterm infants had: gestational age at birth (30.0 ± 2.5 weeks), birth weight (1179 ± 247 g), 27.5% had bronchopulmonary dysplasia, and 45% received mechanical ventilation. Preterm infants had lower median z-scores in comparison to term infants for the following parameters (p < 0.05): FVC (-0.3 vs. 0.7), FEV0.5 (-0.5 vs. 0.9), FEV0.5/FVC (-0.6 vs. -0.5), FEF50 (-0.4 vs. 0.9), FEF75 (-0.3 vs. 0.8), FEF85 (-0.1 vs. 0.6) and FEF25-75 (-0.5 vs. 1.1). No term child had abnormal lung function, compared to 39.2% of preterm infants (p = 0.001). Factors associated with abnormal pulmonary function were lower gestational age at birth, small for gestational age, need for mechanical ventilation and presence of recurrent wheezing. Preterms had a high prevalence of abnormal pulmonary function and lower pulmonary function in comparison to term infants. Prematurity, intrauterine growth restriction, respiratory support and recurrent wheezing were associated with abnormal pulmonary function.