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1.
Exp Eye Res ; 240: 109809, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38311284

RESUMEN

The ocular lens is the primary organ within the eye responsible for accommodation. During accommodation, the lens is subject to biomechanical forces. We previously demonstrated that stretching the porcine lens can increase lens epithelial cell proliferation. Although murine lenses are commonly employed in lens research, murine lens stretching has remained unexplored. Murine lens stretching thus represents a novel source of potential discovery in lens research. In the present study, we describe a method for stretching the murine lens by compressing the murine globe embedded in a hydrogel. We hypothesized that, as the eye is compressed along the optic axis, the lens would stretch through zonular tension due to the equatorial region of the eye bulging outward. Our results showed that this led to a compression-dependent increase in murine lens epithelial cell proliferation, suggesting that compression of the embedded murine globe is a viable technique for studying the mechanobiology of the lens epithelium.


Asunto(s)
Hidrogeles , Cristalino , Animales , Porcinos , Ratones , Acomodación Ocular , Proliferación Celular
2.
Am J Obstet Gynecol ; 228(2): 217.e1-217.e14, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35970202

RESUMEN

BACKGROUND: Delayed cord clamping and umbilical cord milking provide placental transfusion to vigorous newborns. Delayed cord clamping in nonvigorous newborns may not be provided owing to a perceived need for immediate resuscitation. Umbilical cord milking is an alternative, as it can be performed more quickly than delayed cord clamping and may confer similar benefits. OBJECTIVE: We hypothesized that umbilical cord milking would reduce admission to the neonatal intensive care unit compared with early cord clamping in nonvigorous newborns born between 35 and 42 weeks' gestation. STUDY DESIGN: This was a pragmatic cluster-randomized crossover trial of infants born at 35 to 42 weeks' gestation in 10 medical centers in 3 countries between January 2019 and May 2021. The centers were randomized to umbilical cord milking or early cord clamping for approximately 1 year and then crossed over for an additional year or until the required number of consented subjects was reached. Waiver of consent as obtained in all centers to implement the intervention. Infants were eligible if nonvigorous at birth (poor tone, pale color, or lack of breathing in the first 15 seconds after birth) and were assigned to umbilical cord milking or early cord clamping according to their birth hospital randomization assignment. The baseline characteristics and outcomes were collected following deferred informed consent. The primary outcome was admission to the neonatal intensive care unit for predefined criteria. The main safety outcome was hypoxic-ischemic encephalopathy. Data were analyzed by the intention-to-treat concept. RESULTS: Among 16,234 screened newborns, 1780 were eligible (905 umbilical cord milking, 875 early cord clamping), and 1730 had primary outcome data for analysis (97% of eligible; 872 umbilical cord milking, 858 early cord clamping) either via informed consent (606 umbilical cord milking, 601 early cord clamping) or waiver of informed consent (266 umbilical cord milking, 257 early cord clamping). The difference in the frequency of neonatal intensive care unit admission using predefined criteria between the umbilical cord milking (23%) and early cord clamping (28%) groups did not reach statistical significance (modeled odds ratio, 0.69; 95% confidence interval, 0.41-1.14). Umbilical cord milking was associated with predefined secondary outcomes, including higher hemoglobin (modeled mean difference between umbilical cord milking and early cord clamping groups 0.68 g/dL, 95% confidence interval, 0.31-1.05), lower odds of abnormal 1-minute Apgar scores (Apgar ≤3, 30% vs 34%, crude odds ratio, 0.72; 95% confidence interval, 0.56-0.92); cardiorespiratory support at delivery (61% vs 71%, modeled odds ratio, 0.57; 95% confidence interval, 0.33-0.99), and therapeutic hypothermia (3% vs 4%, crude odds ratio, 0.57; 95% confidence interval, 0.33-0.99). Moderate-to-severe hypoxic-ischemic encephalopathy was significantly less common with umbilical cord milking (1% vs 3%, crude odds ratio, 0.48; 95% confidence interval, 0.24-0.96). No significant differences were observed for normal saline bolus, phototherapy, abnormal 5-minute Apgar scores (Apgar ≤6, 15.7% vs 18.8%, crude odds ratio, 0.81; 95% confidence interval, 0.62-1.06), or a serious adverse event composite of death before discharge. CONCLUSION: Among nonvigorous infants born at 35 to 42 weeks' gestation, umbilical cord milking did not reduce neonatal intensive care unit admission for predefined criteria. However, infants in the umbilical cord milking arm had higher hemoglobin, received less delivery room cardiorespiratory support, had a lower incidence of moderate-to-severe hypoxic-ischemic encephalopathy, and received less therapeutic hypothermia. These data may provide the first randomized controlled trial evidence that umbilical cord milking in nonvigorous infants is feasible, safe and, superior to early cord clamping.


Asunto(s)
Enfermedades del Recién Nacido , Clampeo del Cordón Umbilical , Cordón Umbilical , Femenino , Humanos , Recién Nacido , Embarazo , Transfusión Sanguínea , Constricción , Estudios Cruzados , Hemoglobinas , Hipoxia-Isquemia Encefálica/etiología , Recien Nacido Prematuro , Placenta , Cordón Umbilical/cirugía , Clampeo del Cordón Umbilical/métodos , Enfermedades del Prematuro/cirugía , Enfermedades del Prematuro/terapia , Enfermedades del Recién Nacido/cirugía , Enfermedades del Recién Nacido/terapia
3.
Am J Perinatol ; 40(6): 630-637, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34062568

RESUMEN

OBJECTIVE: Delayed cord clamping (DCC) and 21 to 30% O2 resuscitation is recommended for preterm infants but is commonly associated with low pulmonary blood flow (Qp) and hypoxia. 100% O2 supplementation during DCC for 60 seconds followed by 30% O2 may increase Qp and oxygen saturation (SpO2). STUDY DESIGN: Preterm lambs (125-127 days of gestation) were resuscitated with 100% O2 with immediate cord clamping (ICC, n = 7) or ICC + 30% O2, and titrated to target SpO2 (n = 7) or DCC + 100% O2 for 60 seconds, which followed by cord clamping and 30% O2 titration (n = 7). Seven preterm (23-27 weeks of gestation) human infants received continuous positive airway pressure (CPAP) + 100% O2 for 60 seconds during DCC, cord clamping, and 30% O2 supplementation after cord clamping. RESULTS: Preterm lambs in the ICC + 100% O2 group resulted in PaO2 (77 ± 25 mm Hg), SpO2 (77 ± 11%), and Qp (27 ± 9 mL/kg/min) at 60 seconds. ICC + 30% O2 led to low Qp (14 ± 3 mL/kg/min), low SpO2 (43 ± 26%), and PaO2 (19 ± 7 mm Hg). DCC + 100% O2 led to similar Qp (28 ± 6 mL/kg/min) as ICC + 100% O2 with lower PaO2. In human infants, DCC + CPAP with 100% O2 for 60 seconds, which followed by weaning to 30% resulted in SpO2 of 92 ± 11% with all infants >80% at 5 minutes with 100% survival without severe intraventricular hemorrhage. CONCLUSION: DCC + 100% O2 for 60 seconds increased Qp probably due to transient alveolar hyperoxia with systemic normoxia due to "dilution" by umbilical venous return. Larger translational and clinical studies are warranted to confirm these findings. KEY POINTS: · Transient alveolar hyperoxia during delayed cord clamping can enhance pulmonary vasodilation.. · Placental transfusion buffers systemic oxygen tension and limits hyperoxia.. · Use of 100% oxygen for 60 seconds during DCC was associated with SpO2 ≥80% by 5 minutes..


Asunto(s)
Hiperoxia , Recien Nacido Prematuro , Lactante , Recién Nacido , Humanos , Embarazo , Animales , Ovinos , Femenino , Clampeo del Cordón Umbilical , Placenta , Oxígeno , Cordón Umbilical/fisiología , Constricción
4.
J Pediatr ; 242: 245-247.e1, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34715091

RESUMEN

Current guidelines support the use of a cardiac monitor during neonatal resuscitation. Infants born preterm randomized to a novel electrocardiogram algorithm displayed a heart rate sooner than the conventional electrocardiogram algorithm. Although resuscitation outcomes were not different, the availability of an earlier heart rate may benefit neonatal providers during high-risk resuscitations. TRIAL REGISTRATION: ClinicalTrials.govNCT04587934.


Asunto(s)
Recien Nacido Prematuro , Resucitación , Algoritmos , Electrocardiografía , Frecuencia Cardíaca , Humanos , Lactante , Recién Nacido , Proyectos Piloto
5.
Am J Perinatol ; 39(8): 904-908, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33142340

RESUMEN

OBJECTIVE: This study aimed to determine whether outcomes differed between infants enrolled in the PREMOD2 trial and those otherwise eligible but not enrolled, and whether the use of waiver effected these differences. STUDY DESIGN: The multicenter PREMOD2 (PREmature infants receiving Milking Or Delayed cord clamping) trial was approved for waiver of antenatal consent by six of the nine sites institutional review boards, while three sites exclusively used antenatal consent. Every randomized subject delivered at a site with a waiver of consent was approached for postnatal consent to allow for data collection. Four of those six sites IRBs required the study team to attempt antenatal consent when possible. Three sites exclusively used antenatal consent. RESULTS: Enrolled subjects had higher Apgar scores, less use of positive pressure ventilation, a lower rate of bronchopulmonary dysplasia, and a less frequent occurrence of the combined outcome of severe intraventricular hemorrhage or death. A significantly greater number of infants were enrolled at sites with an option of waiver of consent (66 vs. 26%, risk ratio = 2.54, p < 0.001). At sites with an option of either approaching families before delivery or after delivery with a waiver of antenatal consent, those approached prior to delivery refused consent 40% (range 15-74% across six sites) of the time. CONCLUSION: PREMOD2 trial demonstrated analytical validity limitations because of the variable mix of antenatal consent and waiver of consent. A waiver of antenatal consent for minimal risk interventional trials conducted during the intrapartum period will be more successful in enrolling a representative sample of low and high-risk infants if investigators are able to enroll all eligible subjects. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03019367. KEY POINTS: · Waiver of consent is when informed consent cannot be obtained prior to delivery.. · Cord milking is a procedure in which blood is pushed (stripped) two to four times towards the newborn.. · Delayed clamping means the umbilical cord is not clamped immediately after birth..


Asunto(s)
Enfermedades del Prematuro , Recien Nacido Prematuro , Constricción , Femenino , Humanos , Lactante , Recién Nacido , Consentimiento Informado , Embarazo , Cordón Umbilical
6.
J Pediatr ; 223: 51-56.e1, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32482392

RESUMEN

OBJECTIVE: To evaluate changes in cerebral oxygenation, peripheral arterial oxygenation, respiratory status, and administered fraction of inspired oxygen during the first 10 minutes of life in premature infants receiving umbilical cord milking compared with delayed cord clamping (DCC). STUDY DESIGN: Premature infants born at 230/7 to 276/7 weeks of gestation were randomized to umbilical cord milking or DCC. A near infrared spectroscopy sensor, pulse oximeter, and electrocardiogram electrodes were placed. Pulse rate, cerebral tissue oxygenation, peripheral oxygen saturation, airway pressure, and fraction of inspired oxygen were collected for 10 minutes in the delivery room. Longitudinal models were used to compare effects of umbilical cord milking and DCC. RESULTS: Fifty-six infants had cerebral oximetry and advanced monitoring at birth. There was an increased incidence of severe intraventricular hemorrhage in infants who received umbilical cord milking compared with DCC (P = .0211). Longitudinal models suggested that peripheral oxygen saturation was higher in the umbilical cord milking group in the first 4 minutes (P = .0221) and that mean airway pressures were lower in the umbilical cord milking group after the first 7 minutes (P = .0072). No statistical differences were observed for fraction of inspired oxygen, cerebral tissue oxygenation, or heart rates. CONCLUSIONS: The data suggest that the rapid transfer of blood during umbilical cord milking may facilitate lung expansion with improved pulmonary blood flow, but may also increase cerebral blood flow, resulting in severe intraventricular hemorrhage. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03145142.


Asunto(s)
Circulación Cerebrovascular , Parto Obstétrico/métodos , Hemodinámica/fisiología , Pulmón/irrigación sanguínea , Cordón Umbilical/irrigación sanguínea , Adulto , Hemorragia Cerebral Intraventricular/etiología , Parto Obstétrico/efectos adversos , Femenino , Humanos , Recien Nacido Extremadamente Prematuro , Recién Nacido , Embarazo , Resultado del Embarazo/epidemiología , Espectroscopía Infrarroja Corta , Factores de Tiempo
7.
JAMA ; 322(19): 1877-1886, 2019 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-31742630

RESUMEN

Importance: Umbilical cord milking as an alternative to delayed umbilical cord clamping may provide equivalent benefits to preterm infants, but without delaying resuscitation. Objective: To determine whether the rates of death or severe intraventricular hemorrhage differ among preterm infants receiving placental transfusion with umbilical cord milking vs delayed umbilical cord clamping. Design, Setting, and Participants: Noninferiority randomized clinical trial of preterm infants (born at 23-31 weeks' gestation) from 9 university and private medical centers in 4 countries were recruited and enrolled between June 2017 and September 2018. Planned enrollment was 750 per group. However, a safety signal comprising an imbalance in the number of severe intraventricular hemorrhage events by study group was observed at the first interim analysis; enrollment was stopped based on recommendations from the data and safety monitoring board. The planned noninferiority analysis could not be conducted and a post hoc comparison was performed instead. Final date of follow-up was December 2018. Interventions: Participants were randomized to umbilical cord milking (n = 236) or delayed umbilical cord clamping (n = 238). Main Outcomes and Measures: The primary outcome was a composite of death or severe intraventricular hemorrhage to determine noninferiority of umbilical cord milking with a 1% noninferiority margin. Results: Among 540 infants randomized, 474 (88%) were enrolled and completed the trial (mean gestational age of 28 weeks; 46% female). Twelve percent (29/236) of the umbilical cord milking group died or developed severe intraventricular hemorrhage compared with 8% (20/238) of the delayed umbilical cord clamping group (risk difference, 4% [95% CI, -2% to 9%]; P = .16). Although there was no statistically significant difference in death, severe intraventricular hemorrhage was statistically significantly higher in the umbilical cord milking group than in the delayed umbilical cord clamping group (8% [20/236] vs 3% [8/238], respectively; risk difference, 5% [95% CI, 1% to 9%]; P = .02). The test for interaction between gestational age strata and treatment group was significant for severe intraventricular hemorrhage only (P = .003); among infants born at 23 to 27 weeks' gestation, severe intraventricular hemorrhage was statistically significantly higher with umbilical cord milking than with delayed umbilical cord clamping (22% [20/93] vs 6% [5/89], respectively; risk difference, 16% [95% CI, 6% to 26%]; P = .002). Conclusions and Relevance: In this post hoc analysis of a prematurely terminated randomized clinical trial of umbilical cord milking vs delayed umbilical cord clamping among preterm infants born at less than 32 weeks' gestation, there was no statistically significant difference in the rate of a composite outcome of death or severe intraventricular hemorrhage, but there was a statistically significantly higher rate of severe intraventricular hemorrhage in the umbilical cord milking group. The early study termination and resulting post hoc nature of the analyses preclude definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT03019367.


Asunto(s)
Hemorragia Cerebral Intraventricular/prevención & control , Constricción , Enfermedades del Prematuro/prevención & control , Recien Nacido Prematuro , Cordón Umbilical , Terminación Anticipada de los Ensayos Clínicos , Femenino , Edad Gestacional , Humanos , Lactante , Muerte del Lactante , Recién Nacido , Enfermedades del Prematuro/mortalidad , Masculino , Evaluación de Resultado en la Atención de Salud , Embarazo
8.
J Pediatr ; 198: 209-213.e3, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29680471

RESUMEN

OBJECTIVE: To determine whether monitoring cerebral oxygen tissue saturation (StO2) with near-infrared spectroscopy (NIRS) and brain activity with amplitude-integrated electroencephalography (aEEG) can predict infants at risk for intraventricular hemorrhage (IVH) and death in the first 72 hours of life. STUDY DESIGN: A NIRS sensor and electroencephalography leads were placed on 127 newborns <32 weeks of gestational age at birth. Ten minutes of continuous NIRS and aEEG along with heart rate, peripheral arterial oxygen saturation, fraction of inspired oxygen, and mean airway pressure measurements were obtained in the delivery room. Once the infant was transferred to the neonatal intensive care unit, NIRS, aEEG, and vital signs were recorded until 72 hours of life. An ultrasound scan of the head was performed within the first 12 hours of life and again at 72 hours of life. RESULTS: Thirteen of the infants developed any IVH or died; of these, 4 developed severe IVH (grade 3-4) within 72 hours. There were no differences in either cerebral StO2 or aEEG in the infants with low-grade IVH. Infants who developed severe IVH or death had significantly lower cerebral StO2 from 8 to 10 minutes of life. CONCLUSIONS: aEEG was not predictive of IVH or death in the delivery room or in the neonatal intensive care unit. It may be possible to use NIRS in the delivery room to predict severe IVH and early death. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02605733.


Asunto(s)
Encéfalo/fisiopatología , Hemorragia Cerebral/etiología , Hemorragia Cerebral/mortalidad , Enfermedades del Prematuro/etiología , Enfermedades del Prematuro/mortalidad , Espectroscopía Infrarroja Corta , Electroencefalografía , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , Resucitación
9.
J Pediatr ; 193: 40-46.e1, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29174079

RESUMEN

OBJECTIVE: To determine if preterm infants with moderate respiratory distress syndrome on continuous positive airway pressure (CPAP) who received surfactant via a laryngeal mask airway (LMA) would have a decreased rate of intubation and mechanical ventilation compared with those on CPAP who did not receive surfactant. STUDY DESIGN: In this prospective, multicenter, randomized controlled trial, 103 premature infants 280/7-356/7 weeks gestation, ≥1250 g and ≤36 hours old on CPAP requiring fraction of inspired oxygen 0.30-0.40 were assigned to receive surfactant administered through an LMA then placed back on CPAP (LMA group) or maintained on CPAP with no surfactant administered (control group). The primary outcome was treatment failure necessitating intubation and mechanical ventilation in the first 7 days of life. RESULTS: Surfactant administration through an LMA (n = 50) significantly decreased the rate of intubation and mechanical ventilation compared with controls (n = 53): 38% vs 64%, respectively, OR 0.30 (95% CI 0.13, 0.70), P = .006, number needed to treat: 4). There were no serious adverse events associated with placement of the LMA or surfactant administration. CONCLUSIONS: In premature neonates with moderate respiratory distress syndrome, surfactant administered through an LMA decreased the rate of intubation and mechanical ventilation. This intervention may have significant impact on clinical care in both high and low resource settings. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01116921.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Máscaras Laríngeas , Surfactantes Pulmonares/administración & dosificación , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Presión de las Vías Aéreas Positiva Contínua/efectos adversos , Presión de las Vías Aéreas Positiva Contínua/estadística & datos numéricos , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Intubación Intratraqueal/estadística & datos numéricos , Masculino , Estudios Prospectivos , Insuficiencia del Tratamiento , Resultado del Tratamiento
10.
JAMA ; 319(21): 2190-2201, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29872859

RESUMEN

Importance: There are potential benefits and harms of hyperoxemia and hypoxemia for extremely preterm infants receiving more vs less supplemental oxygen. Objective: To compare the effects of different target ranges for oxygen saturation as measured by pulse oximetry (Spo2) on death or major morbidity. Design, Setting, and Participants: Prospectively planned meta-analysis of individual participant data from 5 randomized clinical trials (conducted from 2005-2014) enrolling infants born before 28 weeks' gestation. Exposures: Spo2 target range that was lower (85%-89%) vs higher (91%-95%). Main Outcomes and Measures: The primary outcome was a composite of death or major disability (bilateral blindness, deafness, cerebral palsy diagnosed as ≥2 level on the Gross Motor Function Classification System, or Bayley-III cognitive or language score <85) at a corrected age of 18 to 24 months. There were 16 secondary outcomes including the components of the primary outcome and other major morbidities. Results: A total of 4965 infants were randomized (2480 to the lower Spo2 target range and 2485 to the higher Spo2 range) and had a median gestational age of 26 weeks (interquartile range, 25-27 weeks) and a mean birth weight of 832 g (SD, 190 g). The primary outcome occurred in 1191 of 2228 infants (53.5%) in the lower Spo2 target group and 1150 of 2229 infants (51.6%) in the higher Spo2 target group (risk difference, 1.7% [95% CI, -1.3% to 4.6%]; relative risk [RR], 1.04 [95% CI, 0.98 to 1.09], P = .21). Of the 16 secondary outcomes, 11 were null, 2 significantly favored the lower Spo2 target group, and 3 significantly favored the higher Spo2 target group. Death occurred in 484 of 2433 infants (19.9%) in the lower Spo2 target group and 418 of 2440 infants (17.1%) in the higher Spo2 target group (risk difference, 2.8% [95% CI, 0.6% to 5.0%]; RR, 1.17 [95% CI, 1.04 to 1.31], P = .01). Treatment for retinopathy of prematurity was administered to 220 of 2020 infants (10.9%) in the lower Spo2 target group and 308 of 2065 infants (14.9%) in the higher Spo2 target group (risk difference, -4.0% [95% CI, -6.1% to -2.0%]; RR, 0.74 [95% CI, 0.63 to 0.86], P < .001). Severe necrotizing enterocolitis occurred in 227 of 2464 infants (9.2%) in the lower Spo2 target group and 170 of 2465 infants (6.9%) in the higher Spo2 target group (risk difference, 2.3% [95% CI, 0.8% to 3.8%]; RR, 1.33 [95% CI, 1.10 to 1.61], P = .003). Conclusions and Relevance: In this prospectively planned meta-analysis of individual participant data from extremely preterm infants, there was no significant difference between a lower Spo2 target range compared with a higher Spo2 target range on the primary composite outcome of death or major disability at a corrected age of 18 to 24 months. The lower Spo2 target range was associated with a higher risk of death and necrotizing enterocolitis, but a lower risk of retinopathy of prematurity treatment.


Asunto(s)
Discapacidades del Desarrollo/epidemiología , Enterocolitis Necrotizante/epidemiología , Recien Nacido Extremadamente Prematuro , Enfermedades del Prematuro/epidemiología , Oxígeno/sangre , Ceguera/epidemiología , Parálisis Cerebral/epidemiología , Sordera/epidemiología , Femenino , Humanos , Incidencia , Lactante , Mortalidad Infantil , Recién Nacido , Enfermedades del Prematuro/mortalidad , Estimación de Kaplan-Meier , Masculino , Oximetría , Oxígeno/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Minerva Pediatr ; 70(2): 127-132, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27082272

RESUMEN

BACKGROUND: A duration of 30 seconds has been shown to improve the success rate of intubation attempts without any decompensation. There is limited data regarding the detrimental effects of prolonged intubation attempts in preterm infants. The aim was to determine the effect of prolonged intubation attempts on heart rate and oxygen saturation in preterm infants. METHODS: We retrospectively reviewed videos and physiologic data collected during delivery room (DR) resuscitations. Infants who had a functioning pulse oximeter at the time of intubation in the delivery room were analyzed using video and analog recordings. The duration of the intubation attempt was defined as the time the laryngoscope blade was in the infant's mouth. Prolonged intubations were defined as intubations over 30 seconds. Baseline heart rate and saturations were defined as the heart rate and saturation immediately prior to the intubation attempt. Video recording was used to determine time laryngoscope was in the mouth, what other procedures were performed, and whether there was recovery between attempts. Analog data including heart rate, airway pressure and saturation was also recorded. RESULTS: There were 52 intubation attempts in 28 infants. The median (IQR) birth weight and gestational age were 795 (705, 972) grams and 25 (25, 27) weeks. The duration of an intubation attempt was 35 (27, 46) seconds with number of attempts 2 (1, 2). There were 34 intubation attempts greater than 30 seconds (prolonged group) and 18 attempts less than or equal to 30 seconds (short group). Longer attempts did not affect intubation success (successful 34 [25,37] seconds vs. unsuccessful 41[29, 53] seconds; P=0.05). Infants in the prolonged group had a greater decrease in oxygen saturation percentage from baseline (5±8 percent, short intubation group and 13±27 prolonged intubation group; P=0.004). There was also a significant decrease in heart rate beats per minute between the two groups (6±9 in the short intubation group and 23±29 prolonged group; P=0.004). CONCLUSIONS: The currently recommended guideline by the Neonatal Resuscitation Program limiting intubation attempts to less than 30 seconds is supported by stable oxygen saturations and heart rate. Prolonging the intubation more than 30 seconds leads to greater hypoxia and may contribute to increased neonatal morbidity, with no effect on success rate.


Asunto(s)
Recien Nacido Prematuro , Intubación Intratraqueal/métodos , Oxígeno/metabolismo , Resucitación/métodos , Salas de Parto , Femenino , Edad Gestacional , Frecuencia Cardíaca/fisiología , Humanos , Hipoxia/etiología , Recién Nacido , Masculino , Oximetría , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Factores de Tiempo , Grabación en Video
12.
J Pediatr ; 187: 313-317.e1, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28526223

RESUMEN

Infants may benefit if resuscitation could be provided with an intact umbilical cord. Infants identified at risk for resuscitation were randomized to 1- or 5-minute cord clamping. The 5-minute group had greater cerebral oxygenation and blood pressure. Studies are needed to determine whether this translates into improved outcomes. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02827409.


Asunto(s)
Parto Obstétrico/métodos , Resucitación/métodos , Cordón Umbilical/cirugía , Constricción , Estudios de Factibilidad , Femenino , Humanos , Recién Nacido , Masculino , Embarazo , Riesgo , Nacimiento a Término , Factores de Tiempo
13.
J Pediatr ; 178: 75-80.e3, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27574999

RESUMEN

OBJECTIVE: To assess whether providing ventilation during delayed cord clamping (V-DCC) increases placental transfusion compared with delayed cord clamping alone (DCC only). STUDY DESIGN: Inborn premature infants (230/7-316/7 weeks' gestational age) were randomized to receive at least 60 seconds of V-DCC (initial continuous positive airway pressure) with addition of positive pressure ventilation if needed) or without assisted ventilation (DCC only). For the DCC-only group, infants were dried and stimulated by gently rubbing the back if apneic. The primary outcome was the peak hematocrit in the first 24 hours of life. Delivery room outcomes were analyzed from video recordings and a data acquisition system. Hemodynamic measurements were performed with the use of functional echocardiography, near-infrared spectroscopy, and electrical cardiometry. RESULTS: There was no difference in the primary outcome of peak hematocrit in the first 24 hours of life. The onset of breathing was similar between both groups (25 ± 20 and 27 ± 28 seconds, P = .627); however, infants receiving DCC received a greater duration of stimulation than V-DCC (41 ± 19 and 20 ± 21 seconds P = .002). There were no differences in delivery room interventions, early hemodynamics (cerebral oxygenation by near-infrared spectroscopy, cardiac output and stroke volume by electrical cardiometry, or superior vena cava flow by of functional echocardiography), or neonatal outcomes. CONCLUSIONS: V-DCC was feasible but did not lead to any measurable clinical improvements immediately after delivery or reduce subsequent neonatal morbidity. Caretakers should consider providing adequate stimulation before cord clamping. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02231411.


Asunto(s)
Parto Obstétrico/métodos , Respiración con Presión Positiva/métodos , Cordón Umbilical/cirugía , Constricción , Ecocardiografía , Femenino , Hematócrito , Hemodinámica/fisiología , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Placenta/fisiología , Embarazo , Espectroscopía Infrarroja Corta , Factores de Tiempo
14.
J Pediatr ; 176: 62-68.e4, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27344218

RESUMEN

OBJECTIVE: To test whether infants randomized to a lower oxygen saturation (peripheral capillary oxygen saturation [SpO2]) target range while on supplemental oxygen from birth will have better growth velocity from birth to 36 weeks postmenstrual age (PMA) and less growth failure at 36 weeks PMA and 18-22 months corrected age. STUDY DESIGN: We evaluated a subgroup of 810 preterm infants from the Surfactant, Positive Pressure, and Oxygenation Randomized Trial, randomized at birth to lower (85%-89%, n = 402, PMA 26 ± 1 weeks, birth weight 839 ± 186 g) or higher (91%-95%, n = 408, PMA 26 ± 1 weeks, birth weight 840 ± 191 g) SpO2 target ranges. Anthropometric measures were obtained at birth, postnatal days 7, 14, 21, and 28; then at 32 and 36 weeks PMA; and 18-22 months corrected age. Growth velocities were estimated with the exponential method and analyzed with linear mixed models. Poor growth outcome, defined as weight <10th percentile at 36 weeks PMA and 18-22 months corrected age, was compared across the 2 treatment groups by the use of robust Poisson regression. RESULTS: Growth outcomes including growth at 36 weeks PMA and 18-22 months corrected age, as well as growth velocity were similar in the lower and higher SpO2 target groups. CONCLUSION: Targeting different oxygen saturation ranges between 85% and 95% from birth did not impact growth velocity or reduce growth failure in preterm infants.


Asunto(s)
Crecimiento , Oximetría , Oxígeno/metabolismo , Respiración Artificial , Femenino , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Masculino , Oxígeno/administración & dosificación
15.
Am J Perinatol ; 33(3): 297-304, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26731183

RESUMEN

Proficiency in the care of the preterm neonate is paramount to ensuring safe and quality outcomes. Here we review several simple interventions combined with supportive and informative monitoring that assists the care team in facilitating this critical transitional phase of the care of the preterm newborn. We will discuss the use of checklists, avoidance of early cord clamping, resuscitation during delayed cord clamping, early administration of caffeine soon after birth, and the use of additional monitoring (electrocardiogram, carbon dioxide and respiratory function) during resuscitation. This narrative review of the literature explores the current evidence and recommendations for optimal transition of the preterm infant starting in the delivery room. Team communication can be optimized by implementing the use of checklists and pre/postbriefs in the delivery room. Early use of caffeine in preterm infants may improve systemic blood flow and blood pressure. Delayed cord clamping and cord milking provide significant benefits when compared with immediate cord clamping. Optimizing transition at birth is one of the critical aspects of ensuring a good outcome for this vulnerable population.


Asunto(s)
Cafeína/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Salas de Parto/organización & administración , Recien Nacido Prematuro , Nacimiento Prematuro/terapia , Cordón Umbilical/irrigación sanguínea , Presión Sanguínea/efectos de los fármacos , Transfusión Sanguínea , Cafeína/efectos adversos , Estimulantes del Sistema Nervioso Central/efectos adversos , Constricción , Salas de Parto/normas , Femenino , Humanos , Recién Nacido , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Resucitación , Volumen de Ventilación Pulmonar
16.
N Engl J Med ; 367(26): 2495-504, 2012 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-23268664

RESUMEN

BACKGROUND: Previous results from our trial of early treatment with continuous positive airway pressure (CPAP) versus early surfactant treatment in infants showed no significant difference in the outcome of death or bronchopulmonary dysplasia. A lower (vs. higher) target range of oxygen saturation was associated with a lower rate of severe retinopathy but higher mortality. We now report longer-term results from our prespecified hypotheses. METHODS: Using a 2-by-2 factorial design, we randomly assigned infants born between 24 weeks 0 days and 27 weeks 6 days of gestation to early CPAP with a limited ventilation strategy or early surfactant administration and to lower or higher target ranges of oxygen saturation (85 to 89% or 91 to 95%). The primary composite outcome for the longer-term analysis was death before assessment at 18 to 22 months or neurodevelopmental impairment at 18 to 22 months of corrected age. RESULTS: The primary outcome was determined for 1234 of 1316 enrolled infants (93.8%); 990 of the 1058 surviving infants (93.6%) were evaluated at 18 to 22 months of corrected age. Death or neurodevelopmental impairment occurred in 27.9% of the infants in the CPAP group (173 of 621 infants), versus 29.9% of those in the surfactant group (183 of 613) (relative risk, 0.93; 95% confidence interval [CI], 0.78 to 1.10; P=0.38), and in 30.2% of the infants in the lower-oxygen-saturation group (185 of 612), versus 27.5% of those in the higher-oxygen-saturation group (171 of 622) (relative risk, 1.12; 95% CI, 0.94 to 1.32; P=0.21). Mortality was increased with the lower-oxygen-saturation target (22.1%, vs. 18.2% with the higher-oxygen-saturation target; relative risk, 1.25; 95% CI, 1.00 to 1.55; P=0.046). CONCLUSIONS: We found no significant differences in the composite outcome of death or neurodevelopmental impairment among extremely premature infants randomly assigned to early CPAP or early surfactant administration and to a lower or higher target range of oxygen saturation. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and the National Heart, Lung, and Blood Institute; SUPPORT ClinicalTrials.gov number, NCT00233324.).


Asunto(s)
Desarrollo Infantil , Presión de las Vías Aéreas Positiva Contínua , Discapacidades del Desarrollo/epidemiología , Terapia por Inhalación de Oxígeno , Surfactantes Pulmonares/uso terapéutico , Displasia Broncopulmonar/epidemiología , Presión de las Vías Aéreas Positiva Contínua/efectos adversos , Femenino , Estudios de Seguimiento , Humanos , Lactante , Mortalidad Infantil , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recien Nacido Extremadamente Prematuro , Recién Nacido , Evaluación de Resultado en la Atención de Salud , Oximetría , Oxígeno/administración & dosificación , Oxígeno/sangre , Terapia por Inhalación de Oxígeno/efectos adversos , Surfactantes Pulmonares/efectos adversos , Retinopatía de la Prematuridad/epidemiología , Factores Socioeconómicos
17.
Am J Perinatol ; 32(9): 879-86, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25607226

RESUMEN

OBJECTIVE: This study aims to compare the effects of early and late (routine) initiation of caffeine in nonintubated preterm neonates. STUDY DESIGN: A total of 21 neonates < 29 weeks gestational age were randomized to receive intravenous caffeine citrate (20 mg/kg) or placebo either before 2 hours of age (early) or at 12 hours of age (routine). This was an observational trial to determine the power needed to reduce the need for endotracheal intubation by 12 hours of age. Other outcomes included comparisons of cerebral oxygenation, systemic and pulmonary blood flow, hemodynamics, hypotension treatment, oxygen requirement, and head ultrasound findings. RESULTS: There was no difference in the need for intubation (p = 0.08), or vasopressors (p = 0.21) by 12 hours of age. Early caffeine was associated with improved blood pressure (p = 0.03) and systemic blood flow (superior vena cava flow, p = 0.04 and right ventricular output, p = 0.03). Heart rate, left ventricular output, and stroke volume were not significantly affected. Cerebral oxygenation transiently decreased 1 hour after caffeine administration. There were no differences in other outcomes. CONCLUSION: This pilot study demonstrated the feasibility of conducting such a trial in extremely preterm neonates. We found that early caffeine administration was associated with improved hemodynamics. Larger studies are needed to determine whether early caffeine reduces intubation, intraventricular hemorrhage, and related long-term outcomes.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Cafeína/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Circulación Cerebrovascular/efectos de los fármacos , Citratos/administración & dosificación , Frecuencia Cardíaca/efectos de los fármacos , Recien Nacido Extremadamente Prematuro , Oxígeno/sangre , Método Doble Ciego , Ecocardiografía , Femenino , Edad Gestacional , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Proyectos Piloto
18.
J Pediatr ; 164(5): 1045-1050.e1, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24560179

RESUMEN

OBJECTIVE: To determine whether umbilical cord milking (UCM) improves systemic blood flow and reduces neonatal morbidities compared with immediate cord clamping (ICC). STUDY DESIGN: Women admitted to a tertiary care center and delivering before 32 weeks' gestation were randomized to receive UCM or ICC. Three blinded serial echocardiograms were performed in the first 2 days of the infant's life. The primary outcome was measured systemic blood flow (superior vena cava flow) at each time point. RESULTS: Of the 60 neonates who were enrolled and randomized, 30 were assigned to cord milking and 30 to ICC. Neonates randomized to cord milking had greater measures of superior vena cava flow and right ventricular output in the first 6 hours and 30 hours of life. Neonates receiving UCM also had greater serum hemoglobin, received fewer blood transfusions, fewer days on oxygen therapy, and less frequent use of oxygen at 36 weeks' corrected postmenstrual age. CONCLUSIONS: We demonstrate greater systemic blood flow with UCM in preterm neonates compared with ICC. Future large prospective trials are needed to determine whether UCM reduces intraventricular hemorrhage and other long-term morbidities.


Asunto(s)
Recien Nacido Prematuro/fisiología , Atención Perinatal/métodos , Cordón Umbilical , Vena Cava Superior/fisiología , Velocidad del Flujo Sanguíneo , Gasto Cardíaco , Constricción , Ecocardiografía , Femenino , Humanos , Recién Nacido , Masculino , Estudios Prospectivos , Método Simple Ciego , Ultrasonografía Doppler de Pulso
19.
J Pediatr ; 165(2): 240-249.e4, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24725582

RESUMEN

OBJECTIVE: To explore the early childhood pulmonary outcomes of infants who participated in the National Institute of Child Health and Human Development's Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial (SUPPORT), using a factorial design that randomized extremely preterm infants to lower vs higher oxygen saturation targets and delivery room continuous positive airway pressure (CPAP) vs intubation/surfactant. STUDY DESIGN: The Breathing Outcomes Study, a prospective secondary study to the Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial, assessed respiratory morbidity at 6-month intervals from hospital discharge to 18-22 months corrected age (CA). Two prespecified primary outcomes-wheezing more than twice per week during the worst 2-week period and cough longer than 3 days without a cold-were compared for each randomized intervention. RESULTS: One or more interviews were completed for 918 of the 922 eligible infants. The incidences of wheezing and cough were 47.9% and 31.0%, respectively, and did not differ between the study arms of either randomized intervention. Infants randomized to lower vs higher oxygen saturation targets had a similar risk of death or respiratory morbidity (except for croup and treatment with oxygen or diuretics at home). Infants randomized to CPAP vs intubation/surfactant had fewer episodes of wheezing without a cold (28.9% vs 36.5%; P<.05), respiratory illnesses diagnosed by a doctor (47.7% vs 55.2%; P<.05), and physician or emergency room visits for breathing problems (68.0% vs 72.9%; P<.05) by 18-22 months CA. CONCLUSION: Treatment with early CPAP rather than intubation/surfactant is associated with less respiratory morbidity by 18-22 months CA. Longitudinal assessment of pulmonary morbidity is necessary to fully evaluate the potential benefits of respiratory interventions for neonates.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Oximetría/métodos , Oxígeno/uso terapéutico , Surfactantes Pulmonares/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Salas de Parto , Femenino , Humanos , Lactante , Recien Nacido Extremadamente Prematuro , Recién Nacido , Recien Nacido Prematuro , Masculino , Estudios Prospectivos , Encuestas y Cuestionarios , Resultado del Tratamiento , Estados Unidos
20.
J Vis Exp ; (206)2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38647316

RESUMEN

The biomechanical properties of the ocular lens are essential to its function as a variable power optical element. These properties change dramatically with age in the human lens, resulting in a loss of near vision called presbyopia. However, the mechanisms of these changes remain unknown. Lens compression offers a relatively simple method for assessing the lens' biomechanical stiffness in a qualitative sense and, when coupled with appropriate analytical techniques, can help quantify biomechanical properties. A variety of lens compression tests have been performed to date, including both manual and automated, but these methods inconsistently apply key aspects of biomechanical testing such as preconditioning, loading rates, and time between measurements. This paper describes a fully automated lens compression test wherein a motorized stage is synchronized with a camera to capture the force, displacement, and shape of the lens throughout a preprogrammed loading protocol. A characteristic elastic modulus may then be calculated from these data. While demonstrated here using porcine lenses, the approach is appropriate for the compression of lenses of any species.


Asunto(s)
Cristalino , Cristalino/fisiología , Animales , Porcinos , Fenómenos Biomecánicos/fisiología
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