Neopuff™ Infant T-Piece Resuscitator Clinical Paper ... - Spira

Neopuff Infant T-Piece Resuscitator
Clinical Paper Summaries

Ventilation of Very Preterm Infants in the Delivery Room
Arjan B. te Pas and Frans J. Walther
Curr Pediatr Rev 2006; 2: 187-197
AIM: To summarize current evidence on various elements of neonatal ventilation in the delivery room.
DISCUSSION:
Peak Inspiratory Pressure (PIP)
Resuscitation guidelines recommend a PIP between 20-40 cmH 2
O for term and preterm infants. However
these pressures, if maintained for 1 second, cannot establish adequate inflation volumes in asphyxiated
neonates or preterm infants. This means that higher pressures are necessary in the first manual breaths
to open the lungs. To overcome the problems presented with using potentially dangerous high pressures,
prolonged inflation times (15-20 seconds) at 20-25 cmH 2
O may be used to overcome the long time constant
of a fluid filled lung for preterm infants.
Positive End Expiratory Pressure (PEEP)
A 2001 survey showed that 59% of neonatologists in the USA use PEEP during resuscitation. The use of
PEEP up to 12 cmH 2
O in ventilation and resuscitation of infants and lambs increases compliance, oxygenation
and functional residual capacity (FRC). More randomized controlled clinical trials are needed.
Resuscitation Devices
Self-inflating bags are adequate to deliver the required tidal volumes but cannot deliver a constant PIP and
an adequate PEEP. Flow-inflating bags are technically challenging so inexperience and improper techniques
can lead to dangerously high pressures, sometimes 15 cmH 2
O above the target pressure. The Neopuff
is a purpose-built mechanical device which is easy to use, even by inexperienced operators. Studies on
an intubated mannequin revealed that whereas it is difficult to deliver sustained breaths with self and flow
inflating bags, the Neopuff® delivers a more consistent and precise PIP and PEEP even during sustained
inflation.
Oxygen Concentration
International guidelines recommend the use of 100% oxygen during resuscitation. There is mounting concern
that high concentrations of oxygen may act as a lung irritant and trigger inflammatory responses and oxidative
stress in the newborn. However, there is insufficient evidence from existing studies to recommend using
room-air instead of 100% oxygen. Further trials are needed.
Nasal Continuous Positive Airway Pressure (nCPAP)
Using nCPAP directly after resuscitation is a gentle, non-invasive way to keep the lung open by maintaining
lung volume, preventing atelectasis and stimulating respiration. NCPAP also reduces injury to the lung, the
need for intubation in the delivery room, progression to mechanical ventilation and the amount of surfactant
needed. Although the use of nCPAP is associated with a reduction in mortality of preterm infants there is still
insufficient information to evaluate the effectiveness of prophylactic nCPAP in very preterm infants.
TAKE HOME POINTS:
• During resuscitation, it is possible to open the lung using sustained inflations of 5 – 20 seconds.
• The best and easiest way to deliver a consistent and sustained PIP and adequate PEEP is a
pressure-limited mechanical device with a T-piece i.e. the Neopuff® Infant Resuscitator.
• Using PEEP during resuscitation helps maintain FRC, and reduces lung injury, the need for
intubation, mechanical ventilation and surfactant.
• 100% oxygen concentration is still recommended during resuscitation of preterm infants
although there is increasing concern about oxygen toxicity. Further trials required.
• nCPAP is an efficient and gentle way to keep the lung open in the delivery room and may reduce
lung injury and avoid intubation and mechanical ventilation of preterm infants.

Comparison of three manual ventilation devices using an intubated
mannequin
Hussey SG, Ryan CA, Murphy BP.
Arch Dis Child Fetal Neonatal Ed. 2004; 89; F490 – F493
AIM: To compare three devices, the Fisher & Paykel Healthcare Neopuff Infant T-Piece Resuscitator,
anesthesia bag with attached manometer (Intersurgical) and self inflating bag (Laerdal) for manual neonatal
ventilation, using an intubated Fisher & Paykel Healthcare resuscitation doll.
METHOD: The 35 participants were neonatal health workers that ranged from neonatal nurses, consultant
pediatricians and anesthetists, to an emergency medical technician, and a midwife. Participants were
recruited at in-service training days throughout Ireland. The self inflating bag had a pop off valve set to
activate at PIPs (Peak Inspiratory Pressures) in excess of 40 cmH 2
O, but no manometer to reflect current
clinical use. The anesthetic bag did not incorporate a flow control valve, but the operator could control the
volume and pressure of the bag by adjusting egress at the open end of the bag. The Neopuff PIP and
PEEP (Positive End Expiratory Pressure) settings were preset by each participant before testing.
Each participant was asked to provide positive pressure ventilation to an intubated Fisher & Paykel
Healthcare resuscitation doll for two minutes using each device, aiming to achieve a PIP of 20 cmH 2
0
and a PEEP of 4 cmH 2
0 and a breath rate of 40 breaths per minute. They were allowed to observe the
manometer while using the anesthesia bag and Neopuff. They were not allowed to view a timer clock or
their continuous recordings for any of the devices.
RESULTS: Significant differences were found between devices.
Response Self Inflating bag Anesthetic bag Neopuff p Value
Max PIP 75.9 35.5 22.4 -
Mean Max PIP 44.7 (2.3) 22.6 (0.7) 20.4 (0.5) < 0.001
Mean PIP 30.7(1.9) 18.1 (0.4) 20.1 (0.1) < 0.001
Mean PEEP 0.15 (0.03) 2.83 (0.23) 4.41 (0.08) < 0.001
Mean Airway
Pressure
7.6 (0.8)* 8.5 (0.3)* 10.9 (0.3) < 0.001
Mean rate 47.1 (3.0)* 47.3 (2.7)* 39.7 (1.8) < 0.05
% total breaths ≤
21 cm H20 PIP
% total breaths ≥
30 cm H20 PIP
39 (0.07)# 92 (0.02)* # 98 (0.02)* # < 0.001
45 (0.07) # 0*# 0*# < 0.001
Values are mean cm of H20 (SEM – Standard Error of the Mean) except for # which are percentage (SEM)
* Not significantly different within the same row (p > 0.05)

The performance of the Neopuff was more consistent and reliable when compared with the other two
devices. There was a significant statistical difference between the Neopuff and both the anesthesia
bag and self inflating bag with regard to PIP, PEEP, mean airway pressure and breath rate. The self
inflating bag produced negligible PEEP, and greater mean and maximum PIP than the anesthetic bag and
Neopuff.
Using the Neopuff:
• the mean and maximum PIP were more consistent and closer to the target value
• the mean PEEP values were significantly higher and closer to the target value
• the mean airway pressure was significantly greater
• the applied breath rate was more consistent, reliable and closer to the target rate.
There were no significant differences between the performance of the doctors and allied health
professionals.
DISCUSSION: The ability to provide consistent manual ventilation is dependent on the device. Self
inflating devices without a manometer and a PEEP valve give excessively high PIP and minimal PEEP and
should not be used with VLBW infants.
Appropriate use of the anesthetic bag is dependent on adequate training and practice, otherwise the device
is potentially dangerous.
It is not mentioned that in order to provide a safe PIP and consistent PEEP when using the anesthesia bag,
it is necessary to continuously watch the manometer, while when using the Neopuff one is free to watch
the infant.
The PIP and PEEP values provided by the Neopuff are independent of user stress, fatigue level and skill.
TAKE HOME POINTS:
• The Neopuff was the most consistent and reliable device, providing statistically more consistent
and appropriate PIP and PEEP, significantly greater mean airway pressure and a breath rate that
was most consistent and closest to target.
• Self inflating devices without a manometer should not be used.
• This study concludes that the Neopuff should be incorporated into Neonatal resuscitation training
programs to provide PEEP and controlled PIP.

Neonatal resuscitation: raising the bar
Finer N.N. and Rich W.D.
Curr Opin Pediatr 2004; 16: 157-162
AIM: To provide an overview of neonatal resuscitation practices with an emphasis on interventions that are
not currently accepted or adapted into existing resuscitation guidelines.
DISCUSSION:
Resuscitation Environment
In the NICU, an infant has: servo-controlled temperature, continuously monitored vital signs, heated,
humidified and blended respiratory support, accurately controlled PIP and PEEP or CPAP. However, just 5
minutes beforehand during resuscitation an infant has: heart rate determined by palpation or auscultation,
oxygenation determined by color, ventilation using cold, dry, 100% O 2
and poorly controlled PIP and PEEP.
These differences appear paradoxical and irrational.
Temperature Support
The authors report that the percentage of infants in their resuscitation suite (weighing less than 1250g at
birth) with admission temperatures less than 36°C decreased from 33% to 15% by
(1) increasing environmental temperature from 18°C to 25°C,
(2) providing functional radiant warmers, and
(3) providing a polyethylene occlusive wrap as soon as possible after delivery.
Few resuscitation teams offer the necessary servocontrolled temperature support by applying a temperature
sensor to the infant’s skin at delivery.
Oxygen Intervention
Traditionally, 100% oxygen is used during resuscitation of extremely low birth weight (ELBW) infants. Mounting
evidence suggests that decreasing oxygen requirements during the resuscitation of premature infants is
beneficial. However, more randomized trials are required to establish specific outcomes. Even though the
use of gas blenders are a standard practice in the neonatal intensive care unit (NICU) and both compressed
air and oxygen are commonly available facilities, gas blenders are seldom incorporated into resuscitation
beds.
Positive Pressure Ventilation
Continuous prolonged inflations are used in neonatal resuscitation to establish functional residual capacity
(FRC) and larger tidal volumes. There is a need to determine the best methodology to provide adequate but
not excessive ventilation to the premature lung in terms of positive pressure ventilation. T-piece resuscitators
as opposed to self inflating and anesthesia bags have been shown to deliver ventilation more successfully
in that they are easier to use, provide more consistent positive end expiratory pressure (PEEP) and peak
inspiratory pressure (PIP) and are the only devices that can effectively deliver constant prolonged inflation.
TAKE HOME POINTS:
• The current difference in infant care between the delivery room (cold, dry gas, 100% O 2
, and poorly
controlled PIP and PEEP) and NICU (heated/humidified blended gas, accurately controlled PIP and
PEEP or CPAP) appears paradoxical and irrational.
• Using radiant warmers, increasing NICU environmental temperatures and using occlusive wraps are
associated with a significant increase in mean admission temperature and survival of ELBW infants.
• Few resuscitation teams offer the necessary temperature servocontrol at delivery to protect against
hypothermia.
• Most neonatologists attempt to use PEEP during resuscitation. T-piece resuscitation devices are
the most successful at delivering PEEP, PIP and prolonged inflations.

Resuscitation of Premature Infants: What Are We Doing Wrong and Can We Do
Better?
O’Donnell C.P.F., Davis P.G. and Morley C.J.
Biology of the Neonate 2003; 84:76-82
AIM: To outline the principles and efficacy of current neonatal resuscitation devices and techniques and
identify areas of further research. This will lead to better guidelines and international consensus statements
on the appropriate methods used for resuscitation of premature infants.
DISCUSSION:
Role of PEEP
Lamb studies by the authors showed that the use of PEEP during resuscitation improves oxygenation,
respiratory compliance (by 25%) and maintains functional residual capacity (FRC), thereby reducing the
progression to respiratory distress syndrome (RDS).
Resuscitation Devices
The greatest assets of the self-inflating bag are perceived to be the automatic re-expansion and ease of use.
However, these may be falsely reassuring as a large proportion of the delivered breath may be unknowingly
lost through leak around the mask. The self-inflating bag is unable to deliver a consistent PIP - which depends
on the strength and speed of bag compression, the seal of the facemask and the respiratory compliance - or
normally provide PEEP, or deliver prolonged inflations. Pressures produced by Flow-inflating bags can vary
considerably because of difficulties with operator skill in controlling outlet gas flow and bag squeeze. Poor
technique can produce inconsistent PIP and PEEP, and pressures may reach dangerously high levels. The
Neopuff® is a T-piece resuscitation device with a variable PEEP valve, PIP control, and has a manometer
to show delivered pressure. It can produce a constant PEEP for a given flow, PIP for every breath and can
be adjusted according to clinical response. The Neopuff® is easy to use even by relatively inexperienced
operators.
Heat and Humidification during Neonatal Resuscitation
In the NICU, care and attention are given to heat and humidify respiratory gas. It is therefore surprising that
dry, cold gas is used for resuscitation in the delivery room
TAKE HOME POINTS:
• Lamb studies show that PEEP during resuscitation improves respiratory outcomes.
• Re-expansion and ease of use are perceived assets of the self-inflating bag. These may be falsely
reassuring as a large portion of the breath may be unknowingly lost through leak around the mask.
• Flow-inflating bags are difficult to use and therefore produce inconsistent PEEP and sometimes
dangerous pressures.
• The Neopuff® is a T-piece resuscitation device with a variable PEEP valve, PIP control and a
manometer. The Neopuff® is better than self and flow-inflating bags at providing safe consistent
PIP, constant PEEP and delivering prolonged inflations.
• Heated and humidified gas - as opposed to cold and dry - should be considered for resuscitation of
infants, following the preparation of respiratory gases used in the NICU.

Comparison of methods of bag and mask ventilation for neonatal
resuscitation
Finer NN, Rich W, Craft A, Henderson C
Resuscitation 2001, 49: 299-305
AIM: To determine the ability of different operators to reliably deliver pre-determined inspiratory and endexpiratory
pressures for neonatal resuscitation using currently available devices.
METHOD: Five nurses, two neonatal nurse practitioners, four neonatologists, six neonatal fellows, five
pediatric residents and five neonatal respiratory therapists were evaluated over two days. A neonatal
manikin (Laerdal Armonk, NY) with a functional larynx and lungs was utilized for resuscitation. The following
devices were used: a 500 mL latex-free disposable anesthesia type bag (Model 5126 Vital Signs), a
500 mL Jackson-Rees type anesthesia bag (Model E191 Anesthesia Associates) fitted with a Norman
elbow and a flow-control tail-piece and the Neopuff (Fisher & Paykel, Auckland NZ). The participants were
asked to ventilate the manikin with a bag and mask using all three devices for 30 s at a rate of 30 breaths/
min., a peak inspiratory pressure (PIP) and positive end-expiratory pressure (PEEP) of 25 and 5 cmH 2
O,
respectively. Then they were to deliver a breath of 5 s duration, followed by a further 30 s of bag and mask
ventilation, and a second 5 s inflation. The results were analyzed using SigmaStat software.
RESULTS: There were significant differences in PIP and PEEP between operators using either anesthesia
bag (P

The importance of ventilation to effective resuscitation in the term and preterm
infant
Milner A.
Semin Neonatol 2001; 6: 219-224
AIM: To review available guidance data on how ventilatory support should be provided to infants who are slow
to take the first steps in cardiorespiratory adaptation after delivery.
DISCUSSION:
Self-inflating vs. T-piece Technique
Bag and mask resuscitation is relatively ineffective and probably relies on Head’s Paradoxical Reflex to
stimulate inspiratory efforts. Although self-inflating resuscitation devices are most frequently used, the main
factor limiting their performance is the pressure-limiting leaks that prevent the inflation pressure from being
maintained for more than 0.5 seconds. This is insufficient time to deliver adequate ventilation. When using
the T-piece technique, inflation pressures can be maintained for longer periods to overcome the long time
constant of the fluid-filled lung. Studies show that the T-piece device is easier to use, requires only one hand
and produces more effective tidal exchange than self-inflating devices.
Pressures
The intention is that sufficient pressure should be given to produce adequate but not excessive lung expansion
at birth. Current practice is to use inflation pressures of between 20 – 30 cmH 2
O. A self-inflating reservoir
with a pressure limiting valve is commonly used for lung expansion. Very rapid manual compression can
lead to high pressures and most have the provision to override the pressure relief valve leading to pressures
greater than 60 cmH 2
O.
PEEP/CPAP
There is increasing interest in the use of positive end expiratory pressure (PEEP) with resuscitation to help
establish FRC, conserve surfactant and thus reduce the frequency and severity of RDS.
TAKE HOME POINTS:
• Bag and mask resuscitation is relatively ineffective and probably relies on Head’s Paradoxical
Reflex to stimulate inspiratory efforts.
• The performance of self-inflating devices is limited by the pressure-limiting leaks that prevent
inflation times of more than 0.5 seconds.
• A T-piece device can maintain pressure for longer periods, is easier to use, requires only one hand,
and produces more effective tidal exchange.
• There is increasing interest in the role of PEEP to establish FRC and conserve surfactant.

The “Educated Hand”. Can anesthesiologists assess changes in neonatal
pulmonary compliance manually?
Spears RS, Yeh A, Fisher DM, Zwass MS.
Anesthesiology 1991, 75(4): 693-696.
AIM: To evaluate the ability of anesthetic clinicians to detect changes in “pulmonary” compliance during hand
ventilation of an in vitro model.
METHOD: 24 clinicians were divided into 4 experience levels ranging from inexperienced residents to fully
trained pediatric anesthetists. They were tested using 3 different anesthesia circuits i) Mapleson D (Anesthesia
Medical Specialties) ii) pediatric circle system without humidifier and iii) pediatric circle system humidifier with
either a 1L (small) or 2L (large) lung model. These models were intended to correspond to preterm and fullterm
neonatal lungs, respectively. Clinicians were asked to provide 15 cmH 2
O PIP for the small lung and
20 cmH 2
O PIP for the large lung, and airway pressures were detected with a conventional manometer within
the circuit. Measurements were made over a 5 min period. Clinicians were informed that the endotracheal
tube (ETT) on the model could be clamped at any time, and they were instructed to indicate when they
detected this change. They were required to simultaneously record a number of physiological parameters in
an attempt to simulate conditions within an operating room.
RESULTS: In each of the three circuit types, only 4 of the 24 clinicians were able to detect changes in
compliance of the large lung and only 1 of the clinicians detected it in the small lung. The level of experience
of the clinicians did not predict their ability to detect occlusion of the circuit.
DISCUSSION: Hand ventilation of infants during anesthesia is frequently recommended over mechanical
ventilation since it is contended that this allows more rapid detection and compensation for changes in
pulmonary compliance. The changes produced in the study by complete occlusion of the ETT were more
marked than those that might normally occur in the clinical setting. This suggests that these smaller changes
in compliance in-vivo may not be detected when hand ventilating an infant.
TAKE HOME POINTS:
• Anesthetists are not able to consistently detect changes of lung compliance during manual
ventilation of a lung model. Since the level of change in compliance of the model was large,
this suggests that in a real clinical situation they would be unable to detect small changes and
respond appropriately.
• The ability to detect compliance is not related to the clinician’s level of experience.
• If clinicians are unable to detect changes in compliance manually, then the benefits of mechanical
ventilation must be considered.

Evaluation of manometer use in manual ventilation of infants in neonatal
intensive care units.
Howard-Glenn L, Koniak-Griffin D.
Heart & Lung 1990, 19(6): 620-7.
AIM: To investigate the variation in peak inspiratory pressure (PIP) produced by neonatal nurses when
manually ventilating infants, with and without the use of a manometer. Specifically:
• Are nurses with more years of experience better able to control the PIP delivered than less
experienced nurses?
• Are nurses with more years of experience less likely to use manometers than less experienced
nurses?
• Do nurses using manometers have greater success in controlling prescribed PIP than those who
do not use them?
METHOD: Sixty NICU nurses (with experience ranging from 1–26 years) were observed while manually
ventilating 22 intubated infants. This manual ventilation was performed with a 500 mL inflating resuscitation
bag (Rusch Inc.) in the course of regular suctioning. A Pneumogard 1230A device was used to measure
peak airway pressures and an observer recorded whether the nurses looked at the manometer during
each individual breath.
RESULTS: When a manometer was used, the nurses’ mean percentage of success in controlling PIP to
within +/- 2 cmH 2
O of the prescribed value was 78.01%. This value was 41.40% when the manometer was
not used. A significant negative correlation was found between the number of years of NICU experience
that each nurse had and their use of a manometer. There was no significant correlation between the
number of years of NICU experience and the nurses’ ability to control prescribed PIP.
DISCUSSION: While experienced nurses were found to be less likely to make use of a manometer than
less experienced nurses, they were no more likely to deliver the right level of PIP. When nurses ventilated
infants without looking at a manometer the PIP levels often exceeded the prescribed value, sometimes by
two or three times the value. This has clinical implications in terms of an increased risk of lung injury.
TAKE HOME POINTS:
• When manual ventilation was performed with manometers, nurses in this study demonstrated
greater success in controlling PIP.
• Nurses with more experience tended to rely less on manometers and they often exceeded the
prescribed PIP, frequently doubling or tripling the value.
• Nurses overestimated how often they were looking at the manometer. During the middle of the
resuscitation procedure observation number decreased with a decrease in successfully
controlling PIP over that time.
• The development of new equipment specifically designed to facilitate accurate delivery of
prescribed inspiratory pressures during manual ventilation is also recommended. Additionally,
resuscitator equipment with attached safety pressure-relief devices that can be set for a specific
level appropriate to the size of the infant is needed.

Limitations of self-inflating resuscitators.
Finer NN, Barrington KJ, Al-Fadley F, Peters KL.
Pediatrics 1986, 77 (3): 417-420.
AIM: To evaluate the performance of three self-inflating neonatal resuscitation bags.
METHOD: Three examples of three pediatric self-inflating resuscitation bags were tested: Ohio Hope II
Resuscitator (Ohio Medical Products), the PMR-2 Resuscitator (Puritan Medical Products) and the Laerdal
Neonatal Resuscitator (AS Laerdal). The devices were connected to a test lung via an endotracheal tube
and compressed at frequencies from 10 to greater than 60 breaths per minute. Oxygen flows of 5, 10
and 15 L/min were used, with and without a reservoir. Target pressures were 20-25 cmH 2
O, as well as
pressures greater than the pop-off valve (POV) relief pressure. Measurements of airway pressure and
oxygen concentration were continuously recorded. Tidal volume was also intermittently measured using
a pneumotachograph.
RESULTS: All devices, when equipped with reservoirs, delivered a significantly higher oxygen
concentration than when equipped without reservoirs (p

Manual ventilation with a few large breaths at birth compromises the
therapeutic effect of subsequent surfactant replacement in immature lambs
Bjorklund LJ, Ingimarsson J, Curstedt T, John J, Robertson B, Werner O, Vilstrup CT.
Pediatric Research. 1997, 42(3): 348-355.
AIM: To determine whether as few as 6 large breaths, given shortly after birth, would blunt the therapeutic effect of
subsequent surfactant replacement in immature lambs.
METHOD: Five pairs of trachestomised preterm lamb siblings were randomized into 2 groups; one of each pair received
6 large breaths at birth, and the other sibling acted as a control and received normal ventilation. The large breaths
were administered using a Laerdal neonatal resuscitation bag. Breaths were 120-130 mL in size and held at maximal
inspiration for 5s. All lambs were mechanically ventilated with an initial inspiratory pressure of 29 cmH 2
O, but this
was then increased until PaCO 2
was ~6 kPa, up to a maximum of 40 cmH 2
O. PEEP was initially 4 cmH 2
O, but was
increased to 6 cmH 2
O in 2 animals to counteract hypoxia. Surfactant was given at 30 minutes after delivery. Chest
radiographs were taken periodically throughout the study and examined for the presence of pneumothorax. Pressure
Volume (PV) curves were produced by inflating the lungs to an airway pressure of 35 cmH 2
O, maintaining the pressure
for 15 s and then allowing the lungs to passively deflate through a flowmeter. These curves were taken, in addition to
arterial blood gas samples, at multiple intervals through the 4 h study period. Another 3 lambs were given surfactant at
birth, before ventilation was commenced. They were managed and monitored as above.
After death the lungs were sectioned and examined microscopically. The effect of surfactant treatment was classified
as satisfactory if ≥75% of the alveoli were estimated to be air-expanded, and evidence of lung injury was limited. It was
rated as sub-optimal if the estimated proportion of aerated alveoli was between 50 and 75% and unsatisfactory if ≤50%
of alveoli were air-expanded.
RESULTS: Lung fluid taken at birth was found to be severely surfactant deficient in all 8 lambs tested. The PV curve
became steeper with time following surfactant treatment in all lambs that were not exposed to large breaths. This effect
was not seen in the bagged group. There were no significant differences between groups in arterial blood gas values
before surfactant treatment. However, after surfactant treatment PaCO 2
was greater in the bagged lambs despite
attempts to reduce it by increasing inspiratory pressure. PaO 2
was also transiently increased in the control group. Two
of the bagged lambs had pneumothoraces at autopsy.
Each of the 3 lambs given surfactant before the first breath had a higher PaO 2
and inspiratory capacity (IC)/weight, and
a lower PaCO 2
than any of the 10 lambs that were given surfactant at 30min of age. At 4 hours IC/weight and deflation
compliance/weight were greater, and inspiratory pressure less in each of these lambs than in any of those bagged at
birth. The values in the group of sibling controls tended to be intermediate, with some overlap.
DISCUSSION: While 2 of the control lambs were histologically defined as having optimal response to treatment, none of
the bagged lambs were in this category. Two lambs from each group had a sub-optimal response and 3 bagged lambs
and 1 control lamb had an unsatisfactory response to surfactant. In the group who received surfactant at birth, 2 had an
optimal response, and one had a sub-optimal response. At 4 hours, the IC was significantly lower in those animals with
an unsatisfactory response to surfactant than those with an optimal response.
TAKE HOME POINTS:
• “The main result of this study was that a few large breaths (35-40 mL/kg), given at birth to immature
lambs, inhibited the effect on lung mechanics of subsequently instilled natural surfactant.”
• Even when surfactant is administered before the first breath, a maximal inspiratory capacity is
not established until around 1 hour, and there may still be an early period when the lung is sensitive to
overdistension.”
• “A few inflations with volumes that are probably harmless in other circumstances might, when forced
into the surfactant-deficient lung immediately at birth, compromise the effect of subsequent surfactant
rescue treatment. Our findings challenge current neonatal resuscitation practice of rapidly
establishing a normal lung volume by vigorous ventilation.”

NOTE:These clinical paper summaries were written by the Neonatal Group of Fisher & Paykel Healthcare.
Reviews such as this are provided free of charge to assist clinicians in caring for their patients. It is
recommended that the time be taken to review the paper in full.
REF: 185044888 Rev D 2008-11