Robin B. Knobel

Heat loss prevention for preterm infants in the delivery room.

OBJECTIVE:Preterm infants are prone to hypothermia immediately following birth. Among other factors, excessive evaporative heat loss and the relatively cool ambient temperature of the delivery room may be important contributors. Most infants <29 weeks gestation had temperatures <36.4°C on admission to our neonatal unit (NICU). Therefore we conducted a randomized, controlled trial to evaluate the effect of placing these infants in polyurethane bags in the delivery room to prevent heat loss and reduce the occurrence of hypothermia on admission to the NICU.METHODS:After parental consent was obtained, infants expected to be <29 weeks gestation were randomized to intervention or control groups just prior to their birth. Infants randomized to the intervention group were placed in polyurethane bags up to their necks immediately after delivery before being dried. They were then resuscitated per NRP guidelines, covered with warm blankets, and transported to the NICU, where the bags were removed and rectal temperatures were recorded. Control infants were resuscitated, covered with warm blankets, and transported without being placed in polyurethane bags. Delivery room temperatures were recorded so this potentially confounding variable could be assessed.RESULTS:Intervention patients were less likely than control patients to have temperature < 36.4°C on admission , 44 vs 70% (p<0.01) and the intervention group had a higher mean admission temperature, 36.5°C vs 36.0°C (p<0.003). This effect remained significant (p<0.0001) when delivery room temperature was controlled in analysis. Warmer delivery room temperatures (≥26°C) were associated with higher admission temperatures in both intervention and control infants, but only the subgroup of intervention patients born in warmer delivery rooms had a mean admission temperature >36.4°C.CONCLUSIONS:Placing infants <29 weeks gestation in polyurethane bags in the delivery room reduced the occurrence of hypothermia and increased their NICU admission temperatures. Maintaining warmer delivery rooms helped but was insufficient in preventing hypothermia in most of these vulnerable patients without the adjunctive use of the polyurethane bags.

Heat loss prevention in the delivery room for preterm infants : A national survey of newborn intensive care units

BACKGROUND:Hypothermia incurred during delivery room resuscitation continues to cause morbidity in infants <29 weeks gestation. Three recent trials have shown that wrapping such infants instead of drying prevents heat loss, resulting in higher infant temperatures at Newborn Intensive Care Unit (NICU) admission.OBJECTIVE:To describe current NICU practices with respect to wrapping preterm infants to prevent heat loss in the delivery room.STUDY DESIGN:E-mail survey of neonatologists from national registry using a web-based survey tool.RESULTS:Of 411 e-mails successfully delivered, 125 (30%) responded. Most (87%) represented level III NICUs. Almost one-fifth of respondents (20%) use occlusive material instead of drying preterms in the delivery room. Considerable variation exists regarding choice of wrap and duration of use. Few adverse events were reported.CONCLUSION:“In all” was added –This implies 20% of all NICUs changed practice, 20% of level III NICUs responding have changed delivery room resuscitation practices rapidly in response to new evidence. No “gold” standard exists nationally and there is considerable variation in practice. Neonatal resuscitation guidelines for premature infants should include recommendations regarding choice occlusive wrap and application techniques.

Extremely Low Birth Weight Preterm Infants Lack Vasomotor Response in Relationship to Cold Body Temperatures at Birth

Study Objective:This study evaluated peripheral vasoconstriction in extremely low birth weight (ELBW) infants when body temperature decreased during the first 12 h of life.Study Design:An exploratory, within-subjects design with 10 ELBW infants. Abdominal and foot temperatures were measured every minute. Peripheral vasoconstriction (abdominal>peripheral temperature by 2 °C) and abdominal–peripheral temperature difference were also evaluated. Results:Abdominal and peripheral temperatures were significantly correlated within each infant. One 880 g infant exhibited isolated peripheral vasoconstriction; a 960-g infant had abdominal temperatures >1 °C higher than peripheral temperatures. Eight smaller infants exhibited no peripheral vasoconstriction and spent most of their observations with peripheral greater than abdominal temperatures. In eight infants, mean temperature difference was significantly higher when abdominal temperature was <36.5 °C.Conclusion:Most ELBW infants did not exhibit peripheral vasoconstriction during their first 12 h of life, despite low temperatures. ELBW infants’ vasomotor control may be immature during this period.

Implementing practice guidelines and education to improve care of infants with neonatal abstinence syndrome.

PURPOSE:To develop and implement a program for the management of neonatal abstinence syndrome (NAS) and the use of the Finnegan Neonatal Abstinence Scoring Tool (FNAST). We evaluated knowledge gain in nurses as a result of implementation of the practice guidelines and education. SUBJECTS:Participants included 68 nurses employed in a neonatal intensive care unit (NICU) at a single facility. DESIGN:A nonexperimental, pretest/posttest study evaluated change in nursing knowledge about NAS and the use of the FNAST after implementation of evidence-based clinical practice guidelines and an educational project. METHODS:Nurses were tested before and after participation in education about NAS. A subset of 10 nurses was evaluated using the FNAST with videos of infants having NAS. RESULTS:Volunteer participation in the NAS educational project occurred in 81% of the NICU nurses. All nurses showed some improvement in scores on the posttest, with 2% to 44% improvement. All 10 nurses who participated in the interactive DVD test scored 90% or more against the FNAST criterion 1 week after participation in the educational project. CONCLUSION:Evidence-based clinical practice guidelines and education around NAS and the FNAST equip caregivers with the necessary tools to consistently and accurately assess an infant with NAS when using the FNAST.

Thermoregulation and Thermography in Neonatal Physiology and Disease

Introduction: Infrared thermal imaging, or thermography, is a technique used to measure body surface temperature in the study of thermoregulation. Researchers are beginning to use this novel methodology to study cancer, peripheral vascular disease, and wound management. Methods: The authors tested the feasibility of using an FLIR SC640 uncooled, infrared camera to measure body temperature in neonates housed in heated, humid incubators. The authors examined thermograms to analyze distributions between central and peripheral body temperature in extremely low birth weight infants. The authors have also used this technology to examine the relationship between body temperature and development of necrotizing enterocolitis in premature infants. Results: Handheld, uncooled, infrared cameras are easy to use and produce high-quality thermograms that can be visualized in grayscale or color palettes to enhance qualitative and quantitative analyses. Conclusion: Future research will benefit from the use of this noninvasive, inexpensive measurement tool. Nurse researchers can use this methodology in adult and infant populations to study temperature differentials present in pathological conditions.

Optimal Body Temperature in Transitional Extremely Low Birth Weight Infants Using Heart Rate and Temperature as Indicators

OBJECTIVE To explore body temperature in relationship to heart rate in extremely low birth weight (ELBW) infants during their first 12 hours to help identify the ideal set point for incubator control of body temperature. DESIGN Within subject, multiple-case design. SETTING A tertiary neonatal intensive care unit (NICU) in North Carolina. PARTICIPANTS Ten infants born at fewer than 29 weeks gestation and weighing 400 to 1,000 g. METHODS Heart rate and abdominal body temperature were measured at 1-minute intervals for 12 hours. Heart rates were considered normal if they were between the 25th and 75th percentile for each infant. RESULTS Abdominal temperatures were low throughout the 12-hour study period (mean 35.17-36.68 degrees C). Seven of 10 infants had significant correlations between abdominal temperature and heart rate. Heart rates above the 75th percentile were associated with low and high abdominal temperatures; heart rates less than the 25th percentile were associated with very low abdominal temperatures. The extent to which abdominal temperature was abnormally low was related to the extent to which the heart rate trended away from normal in 6 of the 10 infants. Optimal temperature control point that maximized normal heart rate observations for each infant was between 36.8 degrees C and 37 degrees C. CONCLUSIONS Hypothermia was associated with abnormal heart rates in transitional ELBW infants. We suggest nurses set incubator servo between 36.8 degrees C and 36.9 degrees C to optimally control body temperature for ELBW infants.

Case Report: Total Parenteral Nutrition Extravasation Associated with Spinal Cord Compression and Necrosis

A preterm infant, whose course was complicated by sepsis, necrotizing enterocolitis with jejunal perforation, intraventricular hemorrhage and cerebellar hemorrhage, suffered permanent and total paralysis below the neck from extravasation of parenteral nutrition fluids through a femoral venous catheter. MRI imaging revealed extravasation of fluid into the paraspinus musculature with extension into the spinal canal. This fluid was identified as hyperalimentation and intralipid. Postmortem examination found evidence of necrosis of the spinal cord as well as perforation of the right iliac vein.

Thyroid hormone levels in term and preterm neonates.

SCREENING THYROID HORMONE levels in the neonate during the first week of life is important because of their valuable link in identifying congenital hypothyroidism (CH), a condition that leads to mental retardation if left untreated. However, if CH is diagnosed early, it can be treated.

Laboratory blood tests useful in monitoring renal function in neonates.

It is important to monitor renal function in the neonate, especially in premature infants where nephrogenesis is still in process upon birth. The kidneys are responsible for maintaining homeostasis in the extracellular environment by preventing overaccumulation of waste products and electrolytes. This review describes developmental physiology of the renal system as well as laboratory testing to monitor renal function and glomerular filtration in neonates. Drugs that may affect renal function in infants are also discussed.

Congenital cutaneous candidiasis: a case presentation.

When an infant presents in the delivery room with macular and papular skin lesions covering the trunk, extremities, and/or skin folds, the neonatal nurse practitioner covering deliveries must be aware of possible skin lesion differential diagnoses. Among these is congenital cutaneous candidiasis, a rare, usually benign skin infection. If this condition is recognized early, unnecessary testing and treatment of newborns who present with these symptoms might be avoided.