Neonatal resuscitation--a practical assessment

Comparison of Efficacy of Pressure Controlled vs. Traditional Manual Mask Ventilation for Newborn Resuscitation - A Simulation-Based Pilot Randomized Control Trial

OBJECTIVES

To determine efficacy of non-invasive positive pressure face mask ventilation using a ventilator device (NIPPmV) for achieving early effective ventilation compared to that by self-inflating bag (SIB) or T- piece resuscitator (TPR).

METHODS

The authors video recorded 33 trained resuscitators using NIPPmV (provided using ventilator device), SIB [a 500 ml silicone SIB without a positive end expiratory pressure (PEEP) valve] and a TPR. Using a continuous pressure recording system and a neonatal manikin, the authors evaluated the efficacy of the ventilation to achieve early effective ventilation during 30 s of ventilation. The primary outcome was time to achieve effective chest rise. Secondary outcomes were peak inspiratory pressure (PIP), ventilation rate and the need to perform ventilation corrective steps during positive pressure ventilation (PPV) among the devices.

RESULTS

Total 99 videos were recorded. The time(s) taken to achieve the first chest rise was significantly lesser in NIPPmV group compared to SIB and TPR (3.0 ± 1.7 vs. 3.7 ± 1.9 vs. 7.5 ± 5.4, respectively, p <0.001). The mean PIP delivered by NIPPmV compared to SIB & TPR (19.8 ± 1.6 vs. 35.6 ± 7.4 vs. 17.8 ± 2.0 cm H20 respectively; p <0.001) was more accurate with preset PIP. Ventilation, in terms of breath rate, was observed to be controlled more accurately with NIPPmV compared to SIB & TPR (50 vs. 42 vs. 33 per min respectively; p <0.001).

CONCLUSIONS

The non-invasive positive pressure face mask ventilation using a ventilator (NIPPmV) resulted in achieving early, effective and consistent ventilation.

Stimulating and maintaining spontaneous breathing during transition of preterm infants

Most preterm infants breathe at birth, but need additional respiratory support due to immaturity of the lung and respiratory control mechanisms. To avoid lung injury, the focus of respiratory support has shifted from invasive towards non-invasive ventilation. However, applying effective non-invasive ventilation is difficult due to mask leak and airway obstruction. The larynx has been overlooked as one of the causes for obstruction, preventing face mask ventilation from inflating the lung. The larynx remains mostly closed at birth, only opening briefly during a spontaneous breath. Stimulating and supporting spontaneous breathing could enhance the success of non-invasive ventilation by ensuring that the larynx remains open. Maintaining adequate spontaneous breathing and thereby reducing the need for invasive ventilation is not only important directly after birth, but also in the first hours after admission to the NICU. Respiratory distress syndrome is an important cause of respiratory failure. Traditionally, treatment of RDS required intubation and mechanical ventilation to administer exogenous surfactant. However, new ways have been implemented to administer surfactant and preserve spontaneous breathing while maintaining non-invasive support. In this narrative review we aim to describe interventions focused on stimulation and maintenance of spontaneous breathing of preterm infants in the first hours after birth.

Chest Compressions in the Delivery Room

Annually, an estimated 13–26 million newborns need respiratory support and 2–3 million newborns need extensive resuscitation, defined as chest compression and 100% oxygen with or without epinephrine in the delivery room. Despite such care, there is a high incidence of mortality and neurologic morbidity. The poor prognosis associated with receiving chest compression alone or with medications in the delivery room raises questions as to whether improved cardiopulmonary resuscitation methods specifically tailored to the newborn could improve outcomes. This review discusses the current recommendations, mode of action, different compression to ventilation ratios, continuous chest compression with asynchronous ventilations, chest compression and sustained inflation optimal depth, and oxygen concentration during cardiopulmonary resuscitation.

Increasing Respiratory Effort With 100% Oxygen During Resuscitation of Preterm Rabbits at Birth

Background: Spontaneous breathing is essential for successful non-invasive respiratory support delivered by a facemask at birth. As hypoxia is a potent inhibitor of spontaneous breathing, initiating respiratory support with a high fraction of inspired O₂ may reduce the risk of hypoxia and increase respiratory effort at birth. Methods: Preterm rabbit kittens (29 days gestation, term ~32 days) were delivered and randomized to receive continuous positive airway pressure with either 21% (n = 12) or 100% O₂ (n = 8) via a facemask. If apnea occurred, intermittent positive pressure ventilation (iPPV) was applied with either 21% or 100% O₂ in kittens who started in 21% O₂, and remained at 100% O₂ for kittens who started the experiment in 100% O₂. Respiratory rate (breaths per minute, bpm) and variability in inter-breath interval (%) were measured from esophageal pressure recordings and functional residual capacity (FRC) was measured from synchrotron phase-contrast X-ray images. Results: Initially, kittens receiving 21% O₂ had a significantly lower respiratory rate and higher variability in inter-breath interval, indicating a less stable breathing pattern than kittens starting in 100% O₂ [median (IQR) respiratory rate: 16 (4-28) vs. 38 (29-46) bpm, p = 0.001; variability in inter-breath interval: 33.3% (17.2-50.1%) vs. 27.5% (18.6-36.3%), p = 0.009]. Apnea that required iPPV, was more frequently observed in kittens in whom resuscitation was started with 21% compared to 100% O₂ (11/12 vs. 1/8, p = 0.001). After recovering from apnea, respiratory rate was significantly lower and variability in inter-breath interval was significantly higher in kittens who received iPPV with 21% compared to 100% O₂. FRC was not different between study groups at both timepoints. Conclusion: Initiating resuscitation with 100% O₂ resulted in increased respiratory activity and stability, thereby reducing the risk of apnea and need for iPPV after birth. Further studies in human preterm infants are mandatory to confirm the benefit of this approach in terms of oxygenation. In addition, the ability to avoid hyperoxia after initiation of resuscitation with 100% oxygen, using a titration protocol based on oxygen saturation, needs to be clarified.

Outcomes of oxygen saturation targeting during delivery room stabilisation of preterm infants

OBJECTIVE

To determine the association between SpO₂ at 5 min and preterm infant outcomes.

DESIGN

Data from 768 infants <32 weeks gestation from 8 randomised controlled trials (RCTs) of lower (≤0.3) versus higher (≥0.6) initial inspiratory fractions of oxygen (FiO₂) for resuscitation, were examined.

SETTING

Individual patient analysis of 8 RCTs INTERVENTIONS: Lower (≤0.3) versus higher (≥0.6) oxygen resuscitation strategies targeted to specific predefined SpO₂ before 10 min of age.

PATIENTS

Infants <32 weeks gestation.

MAIN OUTCOME MEASURES

Relationship between SpO₂ at 5 min, death and intraventricular haemorrhage (IVH) >grade 3.

RESULTS

5 min SpO₂ data were obtained from 706 (92%) infants. Only 159 (23%) infants met SpO₂ study targets and 323 (46%) did not reach SpO₂80%. Pooled data showed decreased likelihood of reaching SpO₂80% if resuscitation was initiated with FiO₂ <0.3 (OR 2.63, 95% CI 1.21 to 5.74, p<0.05). SpO₂ <80% was associated with lower heart rates (mean difference -8.37, 95% CI -15.73 to -1.01, *p<0.05) and after accounting for confounders, with IVH (OR 2.04, 95% CI 1.01 to 4.11, p<0.05). Bradycardia (heart rate <100 bpm) at 5 min increased risk of death (OR 4.57, 95% CI 1.62 to 13.98, p<0.05). Taking into account confounders including gestation, birth weight and 5 min bradycardia, risk of death was significantly increased with time taken to reach SpO₂80%.

CONCLUSION

Not reaching SpO₂80% at 5 min is associated with adverse outcomes, including IVH. Whether this is because of infant illness or the amount of oxygen that is administered during stabilisation is uncertain and needs to be examined in randomised trials.

Ventilation Strategies during Neonatal Cardiopulmonary Resuscitation

Approximately, 10-20% of newborns require breathing assistance at birth, which remains the cornerstone of neonatal resuscitation. Fortunately, the need for chest compression (CC) or medications in the delivery room (DR) is rare. About 0.1% of term infants and up to 15% of preterm infants receive these interventions, this will result in approximately one million newborn deaths annually worldwide. In addition, CC or medications (epinephrine) are more frequent in the preterm population (~15%) due to birth asphyxia. A recent study reported that only 6 per 10,000 infants received epinephrine in the DR. Further, the study reported that infants receiving epinephrine during resuscitation had a high incidence of mortality (41%) and short-term neurologic morbidity (57% hypoxic-ischemic encephalopathy and seizures). A recent review of newborns who received prolonged CC and epinephrine but had no signs of life at 10 min following birth noted 83% mortality, with 93% of survivors suffering moderate-to-severe disability. The poor prognosis associated with receiving CC alone or with medications in the DR raises questions as to whether improved cardiopulmonary resuscitation methods specifically tailored to the newborn could improve outcomes.

Optimal Chest Compression Rate and Compression to Ventilation Ratio in Delivery Room Resuscitation: Evidence from Newborn Piglets and Neonatal Manikins

Cardiopulmonary resuscitation (CPR) duration until return of spontaneous circulation (ROSC) influences survival and neurologic outcomes after delivery room (DR) CPR. High quality chest compressions (CC) improve cerebral and myocardial perfusion. Improved myocardial perfusion increases the likelihood of a faster ROSC. Thus, optimizing CC quality may improve outcomes both by preserving cerebral blood flow during CPR and by reducing the recovery time. CC quality is determined by rate, CC to ventilation (C:V) ratio, and applied force, which are influenced by the CC provider. Thus, provider performance should be taken into account. Neonatal resuscitation guidelines recommend a 3:1 C:V ratio. CCs should be delivered at a rate of 90/min synchronized with ventilations at a rate of 30/min to achieve a total of 120 events/min. Despite a lack of scientific evidence supporting this, the investigation of alternative CC interventions in human neonates is ethically challenging. Also, the infrequent occurrence of extensive CPR measures in the DR make randomized controlled trials difficult to perform. Thus, many biomechanical aspects of CC have been investigated in animal and manikin models. Despite mathematical and physiological rationales that higher rates and uninterrupted CC improve CPR hemodynamics, studies indicate that provider fatigue is more pronounced when CC are performed continuously compared to when a pause is inserted after every third CC as currently recommended. A higher rate (e.g., 120/min) is also more fatiguing, which affects CC quality. In post-transitional piglets with asphyxia-induced cardiac arrest, there was no benefit of performing continuous CC at a rate of 90/min. Not only rate but duty cycle, i.e., the duration of CC/total cycle time, is a known determinant of CC effectiveness. However, duty cycle cannot be controlled with manual CC. Mechanical/automated CC in neonatal CPR has not been explored, and feedback systems are under-investigated in this population. Evidence indicates that providers perform CC at rates both higher and lower than recommended. Video recording of DR CRP has been increasingly applied and observational studies of what is actually done in relation to outcomes could be useful. Different CC rates and ratios should also be investigated under controlled experimental conditions in animals during perinatal transition.

Resuscitators who compared four simulated infant cardiopulmonary resuscitation methods favoured the three-to-one compression-to-ventilation ratio

AIM

Suboptimal cardiopulmonary resuscitation (CPR) is associated with a poor outcome, and international guidelines state that resuscitators should optimise compression and ventilation techniques with as few interruptions as possible. We investigated compression and ventilation quality during simulated CPR with four compression-to-ventilation (C:V) methods.

METHODS

In this crossover manikin study, 42 pairs of doctors, nurses, midwives and sixth-year medical students from two Norwegian hospitals provided two-minute resuscitation using the 3:1, 9:3 and 15:2 C:V methods and continuous chest compressions at 120 per minute with asynchronous ventilations (CCaV-120). We measured chest compression, ventilation mechanics and the resuscitators' preferences.

RESULTS

C:V methods 3:1 and 9:3 provided comparable chest compressions and ventilation mechanics, whereas 15:2 produced fewer ventilations and lower minute volumes. The CCaV-120 method was significantly less effective than the 3:1 C:V ratio method: the chest compression depth was 1.9 mm lower, there were 25 fewer chest compressions and 21 fewer ventilations per minute, and the minute volume was 69 mL lower. The 3:1 C:V method also provided better coordination between resuscitators.

CONCLUSION

Our comparison of four simulated infant cardiopulmonary resuscitation methods favoured the 3:1 C:V method, and the multidisciplinary group of participants felt it offered the best level of coordination between resuscitators.

A review of approaches to optimise chest compressions in the resuscitation of asphyxiated newborns

OBJECTIVE

Provision of chest compressions (CCs) and/or medications in the delivery room is associated with poor outcomes. Based on the physiology of perinatal asphyxia, we aimed to provide an overview of current recommendations and explore potential determinants of effective neonatal cardiopulmonary resuscitation (CPR): balancing ventilations and CC, CC rate, depth, full chest recoil, CC technique and adrenaline.

DESIGN

A search in the databases MEDLINE (Ovid) and EMBASE until 10 April 2015.

SETTING

Delivery room.

PATIENTS

Asphyxiated newborn infants.

INTERVENTIONS

CCs.

MAIN OUTCOME MEASURES

Haemodynamics, recovery and survival.

RESULTS

Current evidence is derived from mathematical models, manikin and animal studies, and small case series. No randomised clinical trials examining neonatal CC have been performed. There is no evidence to refute a CC to ventilation (C:V) ratio of 3:1. Raising the intrathoracic pressure, for example, by superimposing a sustained inflation on uninterrupted CC, and a CC rate >120/min may be beneficial. The optimal neonatal CC depth is unknown, but factors influencing depth and consistency include the C:V ratio. Incomplete chest wall recoil can cause less negative intrathoracic pressure between CC and reduced CPR effectiveness. CC should be performed with the two-thumb method over the lower third of the sternum. The optimal dose, route and timing of adrenaline administration remain to be determined.

CONCLUSIONS

Successful CPR requires the delivery of high-quality CC, encompassing optimal (A) C:V ratio (B) rate, (C) depth, (D) chest recoil between CC, (E) technique and (F) adrenaline dosage. More animal studies with high translational value and randomised clinical trials are needed.

Resuscitator's perceptions and time for corrective ventilation steps during neonatal resuscitation

BACKGROUND

The 2010 neonatal resuscitation program (NRP) guidelines incorporate ventilation corrective steps (using the mnemonic--MRSOPA) into the resuscitation algorithm. The perception of neonatal providers, time taken to perform these maneuvers or the effectiveness of these additional steps has not been evaluated.

METHODS

Using two simulated clinical scenarios of varying degrees of cardiovascular compromise--perinatal asphyxia with (i) bradycardia (heart rate--40 min(-1)) and (ii) cardiac arrest, 35 NRP certified providers were evaluated for preference to performing these corrective measures, the time taken for performing these steps and time to onset of chest compressions.

RESULTS

The average time taken to perform ventilation corrective steps (MRSOPA) was 48.9 ± 21.4s. Providers were less likely to perform corrective steps and proceed directly to endotracheal intubation in the scenario of cardiac arrest as compared to a state of bradycardia. Cardiac compressions were initiated significantly sooner in the scenario of cardiac arrest 89 ± 24 s as compared to severe bradycardia 122 ± 23 s, p < 0.0001. There were no differences in the time taken to initiation of chest compressions between physicians or mid-level care providers or with the level of experience of the provider.

CONCLUSIONS

Effective ventilation of the lungs with corrective steps using a mask is important in most cases of neonatal resuscitation. Neonatal resuscitators prefer early endotracheal intubation and initiation of chest compressions in the presence of asystolic cardiac arrest. Corrective ventilation steps can potentially postpone initiation of chest compressions and may delay return of spontaneous circulation in the presence of severe cardiovascular compromise.

Forehead reflectance photoplethysmography to monitor heart rate: preliminary results from neonatal patients

Around 5%-10% of newborn babies require some form of resuscitation at birth and heart rate (HR) is the best guide of efficacy. We report the development and first trial of a device that continuously monitors neonatal HR, with a view to deployment in the delivery room to guide newborn resuscitation. The device uses forehead reflectance photoplethysmography (PPG) with modulated light and lock-in detection. Forehead fixation has numerous advantages including ease of sensor placement, whilst perfusion at the forehead is better maintained in comparison to the extremities. Green light (525 nm) was used, in preference to the more usual red or infrared wavelengths, to optimize the amplitude of the pulsatile signal. Experimental results are presented showing simultaneous PPG and electrocardiogram (ECG) HRs from babies (n = 77), gestational age 26-42 weeks, on a neonatal intensive care unit. In babies ⩾32 weeks gestation, the median reliability was 97.7% at ±10 bpm and the limits of agreement (LOA) between PPG and ECG were +8.39 bpm and -8.39 bpm. In babies <32 weeks gestation, the median reliability was 94.8% at ±10 bpm and the LOA were +11.53 bpm and -12.01 bpm. Clinical evaluation during newborn deliveries is now underway.

Provider Adherence to Neonatal Resuscitation Program Recommendations for Coordinated Neonatal Chest Compressions and Ventilations

AIM

Medical providers often do not perform chest compressions in accordance with recommended resuscitation guidelines for adults and children. Little is known regarding how well neonatal providers perform coordinated chest compressions and ventilations. The objective of this study was to characterize Neonatal Resuscitation Program (NRP) trained providers' adherence to NRP recommendations for coordinated chest compressions and ventilations in a simulated setting.

METHODS

Fifty NRP providers performed coordinated chest compressions for three minutes on a neonatal manikin. A compression sensor (accelerometer) was used to monitor and record compression data. Data analyzed included ratio of compressions to ventilation pauses, delivered chest compressions per minute (CC/min), and duration of ventilation pauses.

RESULTS

Delivered CC/min ranged from 61 to 136. The mean CC/min (99, SD 16) was significantly higher than the NRP-recommended value of 90 (p=0.002). Delivered CC/min did not differ from the first 30 seconds to the last 30 seconds of compressions (p=0.91). Duration of ventilation pauses was highly correlated with CC/min (Spearman's rho= -0.98, p<0.001), with a median duration of 0.92 seconds (IQ range (0.84, 1.02).

CONCLUSIONS

NRP trained providers often do not adhere to NRP recommendations for delivery of coordinated chest compressions during simulated cardiac depression. The mean CC/min performed is higher than recommended. Duration of ventilation pauses is highly correlated with delivered CC/min. Future studies should focus on methods to improve the timing of delivered chest compressions by NRP providers to conform to NRP recommendations.

Minute ventilation at different compression to ventilation ratios, different ventilation rates, and continuous chest compressions with asynchronous ventilation in a newborn manikin

Background

In newborn resuscitation the recommended rate of chest compressions should be 90 per minute and 30 ventilations should be delivered each minute, aiming at achieving a total of 120 events per minute. However, this recommendation is based on physiological plausibility and consensus rather than scientific evidence. With focus on minute ventilation (Mv), we aimed to compare today’s standard to alternative chest compression to ventilation (C:V) ratios and different ventilation rates, as well as to continuous chest compressions with asynchronous ventilation.

Methods

Two investigators performed cardiopulmonary resuscitation on a newborn manikin with a T-piece resuscitator and manual chest compressions. The C:V ratios 3:1, 9:3 and 15:2, as well as continuous chest compressions with asynchronous ventilation (120 compressions and 40 ventilations per minute) were performed in a randomised fashion in series of 10 × 2 minutes. In addition, ventilation only was performed at three different rates (40, 60 and 120 ventilations per minute, respectively). A respiratory function monitor measured inspiration time, tidal volume and ventilation rate. Mv was calculated for the different interventions and the Mann–Whitney test was used for comparisons between groups.

Results

Median Mv per kg in ml (interquartile range) was significantly lower at the C:V ratios of 9:3 (140 (134–144)) and 15:2 (77 (74–83)) as compared to 3:1 (191(183–199)). With ventilation only, there was a correlation between ventilation rate and Mv despite a negative correlation between ventilation rate and tidal volumes. Continuous chest compressions with asynchronous ventilation gave higher Mv as compared to coordinated compressions and ventilations at a C:V ratio of 3:1.

Conclusions

In this study, higher C:V ratios than 3:1 compromised ventilation dynamics in a newborn manikin. However, higher ventilation rates, as well as continuous chest compressions with asynchronous ventilation gave higher Mv than coordinated compressions and ventilations with 90 compressions and 30 ventilations per minute.

The two-thumb technique using an elevated surface is preferable for teaching infant cardiopulmonary resuscitation

OBJECTIVES

To determine whether the two-thumb technique is superior to the two-finger technique for administering chest compressions using the floor surface and the preferred location for performing infant cardiopulmonary resuscitation (CPR) (ie, floor, table, or radiant warmer).

STUDY DESIGN

Twenty Neonatal Resuscitation Program trained medical personnel performed CPR on a neonatal manikin utilizing the two-thumb vs two-finger technique, a compression to ventilation ratio of 30:2 for 2 minutes in random order on the floor, table, and radiant warmer.

RESULTS

Compression depth favored the two-thumb over two-finger technique on the floor (27 ± 8 mm vs 23 ± 7), table (26 ± 7 mm vs 22 ± 7), and radiant warmer (29 ± 4 mm vs 23 ± 4) (all P < .05). Per individual subject, the compression depth varied widely using both techniques and at all surfaces. More variability between compressions was observed with the two-finger vs two-thumb technique on all surfaces (P < .05). Decay in compression over time occurred and was greater with the two-finger vs two-thumb technique on the floor (-5 ± 7 vs -1 ± 6 mm; P < .05) and radiant warmer (-3 ± 6 vs -0.3 ± 2 mm; P < .05), compared with the table (-3 ± 9 vs -4 ± 5 mm). Providers favored the table over radiant warmer, with the floor least preferred and most tiring.

CONCLUSIONS

The two-thumb technique is superior to the two-finger technique, achieving greater depth, less variability, and less decay over time. The table was considered most comfortable and less tiring. The two-thumb technique should be the preferred method for teaching lay persons infant CPR preferably using an elevated firm surface.

Part 10: Pediatric basic and advanced life support: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

Note From the Writing Group: Throughout this article, the reader will notice combinations of superscripted letters and numbers (eg, “Family Presence During ResuscitationPeds-003”). These callouts are hyperlinked to evidence-based worksheets, which were used in the development of this article. An appendix of worksheets, applicable to this article, is located at the end of the text. The worksheets are available in PDF format and are open access.

Comparison of three manual ventilation devices using an intubated mannequin

OBJECTIVE

To compare three devices for manual neonatal ventilation.

DESIGN

Participants performed a two minute period of ventilation using a self inflating device, an anaesthesia bag with attached manometer, and a Neopuff device. An intubated neonatal mannequin, approximating a 1 kg infant with functional lungs, was used for the study. Target ventilation variables included a rate of 40 breaths per minute, peak inspiratory pressure (PIP) of 20 cm H2O, and positive end expiratory pressure (PEEP) of 4 cm H2O. The circuit was attached to a laptop computer for data recording.

RESULTS

Thirty five participants were enrolled, including consultant neonatologists, paediatricians, and anaesthetists, paediatric and anaesthetic registrars, and neonatal nurses. The maximum PIP recorded using the self inflating bag, anaesthetic bag, and Neopuff device were 75.9, 35.5, and 22.4 cm H2O respectively. There were significant differences between the devices for mean PIP (30.7, 18.1, and 20.1 cm H2O), mean PEEP (0.2, 2.8, and 4.4 cm H2O), mean airway pressure (7.6, 8.5, and 10.9 cm H2O), % total breaths < or = 21 cm H2O PIP (39%, 92%, and 98%), and % total breaths > or = 30 cm H2O PIP (45%, 0, and 0). There was no difference between doctors and allied health professionals for the variables examined.

CONCLUSION

The anaesthetic bag with manometer and Neopuff device both facilitate accurate and reproducible manual ventilation. Self inflating devices without modifications are not as consistent by comparison and should incorporate a manometer and a PEEP device, particularly when used for resuscitation of very low birthweight infants.

Optimizing chest compression to rescue ventilation ratios during one-rescuer CPR by professionals and lay persons:

OBJECTIVE

To estimate the optimum ratio of chest compressions to ventilations for one-rescuer CPR that maximizes systemic oxygen delivery in children.

METHOD

Equations describing oxygen delivery and blood flow during CPR as functions of the number of compressions and the number of ventilations delivered over time were adapted from the former work of Babbs and Kern. These equations were solved explicitly as a function of body weight, using scaling algorithms based upon principles of developmental anatomy and physiology.

RESULTS

The optimal compression to ventilation (C/V) ratios for infants and younger children increase sharply as a function of body weight. Optimal C/V ratios are lower for professional rescuers, who take less time to deliver a rescue breath, than for lay rescuers, who interrupt chest compressions for longer to perform ventilations. For professional rescuers the optimal C/V ratio, x*, is approximately 1.6 square root W where the W is the patient's body weight in kg. For lay rescuers the optimum C/V ratio is approximately 2.8 square root W. These values can be approximated for children and teens by the following rules of thumb, based upon the age of the victim: "5 + one half the age in years" for professional rescuers and "5 + age in years" for lay rescuers.

CONCLUSIONS

Compression to ventilation ratios in CPR should be smaller for children than for adults and gradually increase as a function of body weight. Optimal CPR in children requires relatively more ventilation than optimal CPR in adults. A universal compression/ventilation ratio of 50:2, targeted to optimize adult resuscitation, would not be appropriate for infants and young children.

Part 9: pediatric basic life support. European Resuscitation Council

The epidemiology and outcome of pediatric cardiopulmonary arrest and the priorities, techniques, and sequence of pediatric resuscitation assessments and intervention differ from those of adults. Current guidelines have been updated after extensive multinational evidence-based review and discussion over several years. Areas of controversy in current guidelines and recommendations made by consensus are detailed. A large degree of uniformity exists in the current guidelines advocated by the AHA, Council on Latin American Resuscitation, Heart and Stroke Foundation of Canada, European Resuscitation Council, Australian Resuscitation Council, and Resuscitation Council of Southern Africa. Differences are currently based on local and regional preferences, training networks, and customs rather than scientific controversy. Unresolved issues with potential for future universal application are highlighted.

Paediatric basic life support: a practical assessment

Current European Resuscitation Council (ERC) guidelines for paediatric basic life support advocate delivery of 20 cycles/min at a compression rate of 100/min and a compression:ventilation ratio of 5:1 (Resuscitation 1997;34:115-27; Resuscitation 1998;37(2):97-100). We have evaluated whether cardiopulmonary resuscitation (CPR) can be delivered at this rate by hospital providers. We recruited 24 rescuers, all of whom had successfully completed a training course in paediatric life support. Each was asked to perform single rescuer CPR on a Resusci-Junior mannequin (Laerdal, Kent, UK) for 5 min, following the current ERC guidelines. Compressions and ventilations were recorded in real time by inductance plethysmography. Maintenance of the 5:1 ratio was ensured by investigator observation. Cycles of CPR in the first and fifth minutes of resuscitation were counted. The average duration of compression, ventilation and 'transfer time' spent between these two activities was calculated as a percentage of the average duration of a cycle of CPR. All 24 rescuers completed 5 min of resuscitation. Twenty-three of 24 were unable to deliver 20 cycles of CPR in either the first minute (range 8-27; median 11; interquartile range (IQR) 10-13.75) or in the fifth minute (8-26; 11.5; 10-13.75). The median (IQR) duration of a cycle of CPR was 5 s in the first and fifth minutes. Transfer time comprised 30% of total cycle time. In this study, over 95% of single rescuers trained in paediatric life support were unable to deliver 20 cycles of CPR/min. The guidelines make no allowance for time spent moving between compression and ventilation activity. Future consensus statements should take account of this transfer time. Any changes in recommendations should obviously be prospectively audited with Utstein-style reporting and studies of practicability.