Humans ; Infant, Low Birth Weight ; physiology ; Infant, Newborn ; Urination

To interpret the flash evoked potential (FVEP) as dynamic high-order responses to natural and experimental stimulation in healthy preterm infants, waveform analysis of FVEP in 36 healthy preterm infants (postconceptional age 28~42 weeks) were performed using an autoregressive analysis. Based on the histogram of damping frequency of different component impulse response waveforms, the waveforms were divided into 4 groups: group I (0 ~ <2 Hz), group II (2 ~ <6.5 Hz), group III (6.5 ~ <12.0 Hz) and group IV (12~25 Hz). The total power, power of component impulse responses (group I~IV), and damping time (group II~IV) changed significantly with increasing postconceptional age (P<0.01 or P<0.05). Identification of an impulse response component with dominant frequency which undergoes a well-identified change with age is considered to be a useful tool for discriminating between normal and abnormal changes in the FVEP with age in healthy preterm infants.
Evoked Potentials, Visual ; physiology ; Female ; Humans ; Infant, Newborn ; Infant, Premature ; physiology ; Male ; Reaction Time ; Sleep ; physiology

OBJECTIVETo investigate the characteristics of the tidal breathing pulmonary function in premature infants with different gestational ages.

METHODSA total of 75 premature infants were classified into three groups according to their gestational ages: <32 weeks, 32-33(+6) weeks and 34-36(+6) weeks. Fifty-five full-term infants (39-40 weeks group) were selected as the control group. All infants were given the tidal breathing pulmonary function test at 3-5 days after birth. Moreover, all infants were given the tidal breathing pulmonary function test again at 40 weeks of the corrected gestational age.

RESULTSAt 3-5 days after birth, the three groups of premature infants had significantly lower inspiratory time, time to peak tidal expiratory flow (tPTEF), and ratio of tPTEF to total expiratory time (tPTEF/tE) than the control group (P<0.05). The parameter values of the tidal breathing pulmonary function were lower when the gestational age was lower. Even at 40 weeks of the corrected gestational age, the three groups of premature infants still had significantly lower tPTEF and tPTEF/tE than the control group (P<0.05).

CONCLUSIONSThe tidal breathing pulmonary function of neonates is influenced by the gestational age. The tidal breathing pulmonary function of premature infants is obviously impaired, and the lower the gestational age, the more obvious the impairment.

Female ; Gestational Age ; Humans ; Infant, Newborn ; Infant, Premature ; physiology ; Lung ; physiology ; Male ; Pregnancy ; Respiration

OBJECTIVELeptin is an adipocyte-derived hormone regulating body weight and energy balance in animals and human being. Although the physiological functions of leptin in human are still unclear, its secretion is closely related to fat mass and energy expenditure in both adults and children. This study investigated whether the plasma leptin level was reduced in connection with the weight loss during the neonatal period and try to find out the role of leptin in body weight regulation and energy balance of premature infants.

METHODSThe radioimmunoassay was used to determine the plasma leptin concentration. The first blood samples were obtained at the delivered, and then collected the samples every two days until the infants' body weight recovered to the birth weight or above. At the same time, the essential fluid and energy for the patients were supplied to keep their physiological functions. One person was appointed to take responsibility to examine the body weight, body length and head circumference. Then computed out their Kaup index from the first day to the seventh or twelfth day.

RESULTSA total of 26 premature infants were selected into the study, of which 14 cases were male and 12 female, and their gestational age ranged from 30 to 36 weeks. There was a significantly positive correlation between the premature newborns' body weight loss and their plasma leptin levels (the 1st day: n = 26, r = 0.766; the 3rd day: n = 26, r = 0.636; the 5th day: n = 26, r = 0.629; the 7th day: n = 26, r = 0.717; the 9th-12th day: n = 24, r = 0.587; P < 0.01). The time of body weight loss and the plasma leptin level which declined to extremely low were positively correlated. (r = 0.611, P < 0.01). The time when body weight loss declined to extremely low in 26 premature infants ranged form the 3rd to the 9th day after birth [(5.2 +/- 1.6) day], and that of the plasma leptin levels ranged form the 3rd to the 8th day after birth (4.7 +/- 1.4) day. The maximal ranges of the body weight loss and the plasma leptin decrease in 26 premature infants were (6.5 +/- 3.0)% and (59.6 +/- 11.3)%, respectively. In addition, there were significantly positive correlations among the plasma leptin level, the premature newborns' body length (the 1st day: n = 26, r = 0.609, P < 0.01; the 3rd day: n = 26, r = 0.419, P < 0.05; the 5th day: n = 26, r = 0.583, P < 0.01; the 7th day: n = 26, r = 0.626, P < 0.01; the 9th-12th day: n = 24, r = 0.482; P < 0.05), and the Kaup index (the 1st day: n = 26, r = 0.634; the 3rd day: n = 26, r = 0.534; the 5th day: n = 26, r = 0.542; the 7th day: n = 26, r = 0.611; the 9th-12th day: n = 24, r = 0.539; P < 0.01). Although the head circumference correlated positively with the plasma leptin level at the first week after the delivery (the 1st day: n = 26, r = 0.580, P < 0.01; the 3rd day: n = 26, r = 0.417, P < 0.05; the 5th day: n = 26, r = 0.426; P < 0.01). There was a lower correlation between them one week after the delivery (the 7th day: n = 26, r = 0.369; the 9th-12th day: n = 24, r = 0.323; P > 0.05).

CONCLUSIONThere was a significantly positive correlation between the plasma leptin level and the premature newborns weight loss. Leptin may participate in the regulation of energy balance and body weight of premature infants during neonatal life. Leptin may play an important role in growth and development of premature infants.

Body Weight ; physiology ; Humans ; Infant, Newborn ; Infant, Premature ; Leptin ; blood ; Radioimmunoassay ; Time Factors ; Weight Loss ; physiology

One hundred infants were divided into the following 3 gestational age (GA) groups: (I) premature infants (n = 30) with the gestational age between 29 and 32 weeks; (II) premature infants (n = 30) with the gestational age between 33 and 36 weeks; (III) full-term infants (n = 40). The recorded responses of all infants to pain included the behavioral responses to painful stimuli (cry, facial activity and limbs movement) and the variety of heart rate. The results indicated that the infants of 3 groups had different degree response to various painful stimuli. Pain expression in full term infants was more significant than premature infants to same stimuli. 33-weeks GA infants were differential from 29-weeks GA infants. Full term infants showed more vertical mouth stretch and more taut tongue and more hand to mouth than premature infants, but more horizontal mouth stretch in premature infants.
Gestational Age ; Infant, Newborn/*physiology ; Pain/*physiopathology ; Pain Measurement/*methods

OBJECTIVETo observe the effects of neurally adjusted ventilatory assist (NAVA) on the patient-ventilator synchrony, gas exchange, and ventilatory parameters in preterm infants with respiratory distress syndrome (RDS) during mechanical ventilation.

METHODSTen preterm infants with RDS received mechanical ventilation in NAVA mode for 60 minutes and in synchronized intermittent mandatory ventilation (SIMV) mode for 60 minutes, and the two modes were given in a random order. The vital signs, patient-ventilator synchrony, blood gas values, and ventilatory parameters were compared between the two ventilation modes.

RESULTSInspiratory trigger delay was significantly shorter with NAVA than with SIMV (P<0.05). There were no significant differences in arterial pH, PaCO2, PaO2 and PaO2/FiO2 between the two modes. The spontaneous respiratory rate, peak inspiratory pressure (PIP), electrical activity of the diaphragm and work of breathing were significantly lower in NAVA than in SIMV (P<0.05).

CONCLUSIONSCompared with SIMV, NAVA appears to improve patient-ventilator synchrony, decrease PIP, and reduce diaphragmatic muscle load and work of breathing in preterm infants with RDS during mechanical ventilation.

Diaphragm ; physiology ; Female ; Humans ; Infant, Newborn ; Infant, Premature ; Male ; Respiration, Artificial ; methods ; Respiratory Center ; physiology ; Respiratory Distress Syndrome, Newborn ; therapy

OBJECTIVEInadequate postnatal nutritional support is an important factor contributing to growth failure, which leads to poor neurological outcome. In this study, co-word analysis was used to investigate the research on nutrition of premature infants over the last six years in China, describe the research trend in this field in China, and provide possible directions for future research.

METHODSA literature search was performed in January 2013 using the CNKI database and the key words "preterm infant" and "nutrition". A total of 772 articles were retrieved. Then high-frequency key words were extracted using Excel 2010 to create a co-occurrence matrix. Finally, a visualized network was built using Ucinet 6.0.

RESULTSThe knowledge domain map of research on nutritional support for premature infants in China showed that the major topic of relevant research is still the combination of parenteral nutrition and enteral nutrition, with the goal of maintaining appropriate growth rates in premature infants. Researchers have paid much attention to the adverse effects of parenteral nutrition. Feeding intolerance is still the main problem in nutritional support, especially enteral nutrition, for premature infants.

CONCLUSIONSA visualized network of current research on nutrition of premature infants in China has been created, and a knowledge domain map has been drawn to reflect the hot topics in this field of study over the last six years.

Enteral Nutrition ; Humans ; Infant Nutritional Physiological Phenomena ; Infant, Newborn ; Infant, Premature ; physiology ; Parenteral Nutrition

OBJECTIVETo explore the relation of the anogenital distance (AGD) with cryptorchidism in male newborns.

METHODSThis study included 350 male infants delivered in two community hospitals between September 2013 and September 2014. Within 24 hours after birth, a pediatric surgeon measured the AGD of the neonates and determined whether they had cryptorchidism. According to the testicular position, we divided the undescended testes into three types: upper scrotal, inguinal, and non-palpable.

RESULTSTotally 39 cases of cryptorchidism were found in the 350 newborns. The AGD of the cryptorchidism infants was significantly shorter than that of the normal neonates ([2.01 ± 0.22] vs [2.35 ± 0.19] cm, P < 0.01), and statistically significant differences remained even when preterm and low birth-weight infants were excluded ([2.32 ± 0.14] vs [2.06 ± 0.19] cm; (2.37 ± 0.17) cm vs (2.12 ± 0.12) cm, all P < 0.01). The newborns with higher-position cryptorchidism had a shorter AGD, though with no significant difference (F = 0.434, P > 0.05). No significant differences were observed in the AGD between unilateral and bilateral cryptorchidism ([1.96 ± 0.13] vs [2.02 ± 0.17] cm, P > 0.05).

CONCLUSIONShorter AGD is associated with a higher incidence of cryptorchidism in male newborns. AGD could serve as a potential biomarker for disruption of androgen action during the male programming window period.

Androgens ; physiology ; Cryptorchidism ; diagnosis ; Humans ; Infant, Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Male ; Perineum ; abnormalities

PURPOSE: Low-birth-weight(LBW) neonates often need multiple transfusions during their neonatal period. The routine use of the 500ml mono-bag system in Korea, even in neonatal transfusions, results in a great waste of blood and exposes the neonate to multiple blood donors. To reduce the waste of blood and the number of exposures, we used quadruple blood bags in the transfusion of LBW neonates. METHODS: From November 1995 to April 1997, 86 neonates weighing less than 2,000gm were enrolled in this study. Forty-four of those neonates needed blood transfusions. Using quadruple blood bags, we were able to safely make 3 units of packed red blood cell(RBC) from each directed donors. RESULTS: Seventy-seven units of packed RBC could be made from 29 directed donors and 58 of those units were actually transfused to the 25 neonates. Blood age of the directed donor blood prepared in the quadruple blood bags were relatively older than those of bank bloods at the time of transfusion, thus, K+ concentration was higher but the total K+ amounts infused through transfusions were within tolerable ranges in both groups. CONCLUSION: Using quadruple blood bag in the transfusion of LBW neonates, we could reduce the number of donor exposures and also the waste of blood. K+ loads to the neonates through the transfusion of directed donor blood were within tolerable range in the neonatal physiology.
Blood Donors ; Blood Transfusion ; Humans ; Infant, Low Birth Weight* ; Infant, Newborn ; Infant, Newborn* ; Korea ; Physiology ; Tissue Donors

Cerebral Cortex ; growth & development ; physiology ; Evoked Potentials, Visual ; physiology ; Humans ; Infant, Newborn ; Infant, Premature ; growth & development ; Sensory Thresholds ; physiology ; Vision, Ocular ; physiology ; Visual Acuity ; physiology ; Visual Perception ; physiology