Near Term Infants Susan M. Ludington, CNM, Ph.D., FAAN Walters Professor of Pediatric Nursing Case Western Reserve University Susan.firstname.lastname@example.org
Near Term/Late Term • Infants born at 34, 35, 36 and 37 weeks gestational age are called NEAR TERM (AKA Late Preterm) Infants -4-5 weeks before due date • Near terms have a higher rate of post-discharge rehospitalization and illness than fullterm infants (Raju et al., 2006; Wang et al., 2004)
Prevalence of Near Term Births • Near terms comprise the largest and a growing proportion of preterm (<37 wks GA) births (Mathews & MacDorman, 2007). • Represent approximately 7% of births • in US near terms are 6.4-8.5% of all births • in Canada 7.7% of infants are born <37 weeks and 5.6% of all infants are 34-36 weeks GA (Santo-Donato, 2006).
Near term characteristics • AGA • Normal APGARS • Usually go home with MOM in 2-3 days • Considered to be healthy, like full term infant, BUT
They are more like preterm infants than fullterm infants • “ though often treated like full term newborns, near-term newborns are at risk for same problems that prematures experience: respiratory distress, hyperbilirubinemia, feeding problems, and neurodevelopmental delays” (AWHONN).
1. Increased Mortality 2. Increased Morbidity 3. Respiratory Instability –apnea 4. Cardiovascular instability 5. Thermoregulation 6. Hypoglycemia 7. Sepsis 8. Hyperbilirubinemia 9. Feeding Problems 10. Neurodevelopmental delay
Increased Mortality • 2001 mortality rate for 32-36 GA=8.9/1000 • 2002 mortality rate =9.2/1000 (MacDorman et al., 2005) with similar results in 2004 (Mathews & MacDorman, 2007) • Kangaroo Care decreases mortality (Kambarami, Chided & Pereira, 2003; Worku & Kassie, 2005)
Increased Morbidity • Wang et al., 2004 90 near term vs 95 FT • Near terms had more evaluations for sepsis, hypoglycemia, breathing probs, jaundice, and 27% needed IV fluids (only 5% FT needed IV fluids). • LOS was longer and costs for near terms were $2630 more than FT • Kangaroo Care reduces LOS (27.2 days vs 34.6) (Ramanathan et al., 2001)
Respiratory Instability • Due to ↓ diffusion capability – lungs underdeveloped, few gas exchange sites at 29-35 wks, surface area in alveoli ↑ at 36+ wks • Due to ↓ fluid clearance ability –esp C/S • Due to ↓ surfactant →↓ elasticity of alveolae
Respiratory Assessment: • Check for Apnea of Prematurity & Periodic Breathing – Biggest use of home monitor • < 20 secs with spontaneous recovery • < 20 secs with HR↓ &/or cyanosis, stimulate + meds • > 20 secs – stimulate + meds
Apnea Treatment • 3 types of Apnea • 1. Central (controlled by brain, airflow goes in and out of lungs without respiratory effort) • 2. Obstructive (due to airway obstruction like flexed neck, airflow goes in but does not go down into lungs but respiratory effort continues • 3. Mixed (combination of central & obstructive)
Apnea reduction by 75% during KMC Ludington-Hoe et al Neonatal Network 1994
KC for apnea: • Apnea rarely occurs during KC (Chen et al., 2000; Clifford & Barnsteiner, 2001; Ludington-Hoe et al., 2004; Tornhage et al., 1999) • Apnea does not increase during KC (Bohnhorst et al., 2001, 2004; Kadam et al., 2005) • Apnea may decrease during KC (Ludington-Hoe et al., 1994; Hadeed et al., 1995; Meier, 2003) • Because… apnea mostly occurs during active sleep and arousals and these are minimized during Kangaroo Care (Ludington-Hoe et al. 2006; Lehtonen & Martin, 2004)
Cardiovascular Instability • When changing position, being manipulated, feeding, or having apnea, HR ↓ → BP vacillates • Full term BP = 50-85 mmHg • Near term BP = 25-50 mmHg
Cardiovascular Instability TX • Monitor HR and skin color • Mimimize agitation, avoid crying – stress changes heart rate KC produces calm (Morelius et al., 2005; Moore et al., 2007) • Prevent crying or answer quickly to prevent foramen ovale shunting (Ludington-Hoe, Cong & Hashemi, 2002). Crying is rare in KC (Ludington, 1990; Anderson et al. 2003) and KC ↓crying (Chwo et al., 2002; Erlandsson et al., 2007: Lai et al., 2005, Moore et al., 2007)
Hypothermia is big concern • Lose body heat due to large surface area (lose 40% through head alone), no shivering thermogenesis ability, limited brown fat supplies (only 207% of total weight at birth in near terms), limited glucose and oxygen reserves for thermogenesis, and spend most of reserves on maintaining temperature (near term spends twice the O2 consumption to stay warm than a fullterm infant does).
Hypothermia Treatment: • Maintain warm environmental temp becuz a drop of 2° doubles O2 consumption rate and ↑ anaerobic metabolism • Do not wean from incubator until at least 1500 grams • KC – infants are warmer in KC than in any incubator or radiant warmer (Ludington-Hoe et al., 2000) • Best temp for near term is 36.8°C (36.5-37.4)
Advantages of Kangaroo Care to Thermal Regulation • Mother conducts heat to infant (Bergstrom et al., 2007; Ludington-Hoe et al., 2000, 2004, 2005) • KC warms entire body, not just trunk (Christidis et al., 2003) • KC warms and keeps warm without causing change in O2 consumption nor metabolic rate (Karlsson, 1996) • KC maintains temp in neutral thermal zone (Jonas et al., 2007; Ludington-Hoe et al., 2004; Moore et al., 2007; Ndiaye et al., 2006) • KC is more efficient for rewarming than any device (Galligan, 2006) • AAP recommends KC for thermoregulation (AAP, 2005)
Sepsis – 4 times more common in near term than in term infants • Acquire infections in utero, during delivery, and during postpartum • Early sign is ↑ apnea, poor feeding, and acting just “not right” • TX: work up, close monitoring, antibiotics and active KANGAROO CARE (ideally with Mother’s own milk for enteromammary and enterodermal pathways (Schanler, 2001; Schanler et al., 2005). KC reduces infection (Conde-Agudelo et al., 2003; Charpak et al., 2001, Kambarami et al., 1998)
Hypoglycemia – causes seizures • Five times more often in near term than full term infants. • Due to delivery (no more coming from mother and when it was, infant’s level was only 60% that of mother’s), slow start up in first 2-4 hours of infant’s own gluconeongenesis and glycogenolysis, so • All newborns will have drop unless you prevent it with treatment
Hypoglycemia Treatment -1 • Monitoring glucose level <40-45mg/dl New 2007 guidelines say do it at 12, 24, 48 and pre-discharge & use nomogramfor near term infants (Bhutani & Johnson, 2006; Beachy, 2007) • Watch for apnea, lethargy, jittery behavior, tachypnea, hypothermia • Common treatment is early feeds and IV glulcose with bolus of 2-4 ml/kg D10W then continuous infusion based on 4-8 mg/kg/minute
Hypoglycemia Treatment -2 • Keep infant in Kangaroo Care. Over first 90 minutes of life, even without feeding, blood glucose will stay closer to normal (Anderson et al., 2003; Christensson et al., 1996; Mazurek et al., 1999) because staying warm promotes euglycemia (Chantry, 2005) • Feed infant breastmilk while in KC because this reduces hypoglycemia (American Academy of BF Med)
Feeding Problems – gut mature at 34 weeks but still growing and building integrity of sphincters Though Breast Milk is best, many BF problems: 1, decreased milk intake 2 ° inefficient (immature) sucking & inadequate feeding volume, & 2. consequent reduced maternal milk supply (Shapiro-Mendoza et al., 2006; Tomashek et al., 2006; Jain & Cheng, 2006; Hall et al., 2000)
Kangaroo Care CLEARLY promotes better breastfeeding, even in infants as low as 23 weeks GA (Moore & Anderson, 2007; Moore, Anderson & Bergman, 2007; Carfoot et al., 2005) and increases milk production (CDC, 2005; Hurst et al., 1997) • Mother’s Milk Club in Chicago (Meier, 2003) • Uninterrupted KC, daily KC, pumping near baby, KC before anticipated feeding time, don’t let sleep beyond 4 hours • feed 8-12 times/day (includes night) and mothers need support & EARLY PUMPING Aim for 15-20 gm/kg/day gain
Hyperbilirubinemia is common • ↑bilirubin usually occurs in 1st week, so the earlier the discharge the more likely readmission (Watchko, 2006) • 80% of preterms develop Hyperbili (Sola, 2007) • Kernicterus in common (Bhutani & Johnson, 2006) and • Dehydration is common (Jones et al., 2003) • Due to immaturity of liver and intestine, ↑ production, ↓elimination, and more common in Breastfed infants
Assessment of Bilirubinemia • Expect hyperbilirubinemia in near terms (80%-Sola, 2007) • Do first assessment at 12 hours of life – transdermal (icterometer) from forehead and nose tip. If >2 in 1st 24 hrs, estimated mean bili=5.5-8.7 mg/dl (Facchini et al., 2007). If >3 after 24 hours of life, then take total bili transcutaneously and if > 11 mg/dl, take serum value and compare to critical chart (Bhutani & Johnson, 2007) • Initiate phototherapy when critical values are at or near 40th Percentile on NOMOGRAM for near terms (Bhutani, Johnson, Sivieri, 1999) • Assess bili level 24 hours after discontinuing treatment and ALWAYS BEFORE DISCHARGE. Only discharge if bilirubinemia < 15 mg/dl. • If bilirubinemi = or > 20mg/dl, restart phototherapy. • REMEMBER that 48Hours of Phototherapy leads to oxidative stress and metabolic derangements in near term infants (Sola, 2007).
What to Tell Parents: • Infant has special, preemie-like needs • Infant needs special monitoring • Give them AWHONN near term booklet: Optimizing Health of Near Term Infants. Available from www.awhonn.org/store, phone 800-354-2268 (US) or 800-245-0231(Canada), fax: 202-728-6726, mail: AWHONN, Dept. 4015, Washington, DC 20042-4015. • AND DO AS MUCH KC AS POSSIBLE (AAP, 2005; CDC, 2005; WHO 2004)
References • Beachy JM. 2007. Investigating jaundice in the newborn. Neonatal Network 26(5), 327-333. • Bhutani VK & Johnson L. 2006. Kernicterus in late preterm infants cared for as term healthy infants. Semin Perinatology 30, 89-97. • Hall RT, Simon S,Smith MT. 2000. Readmission of breastfed infants in the first 2 weeks of life. J. Perinatol 20, 432-437. • Jain S & Cheng J. 2006. Emergency department visits and rehospitalizations in late preterm infants. Clin Perinatol 33, 935-945. • Jones G, Stekete RW, Black RE, Chutta ZA, Morris SS, Bellagio Child Survival Study Group. 2003. How many child deaths can we prevent this year? Lancet 362, 839-852.
Bibliography Cont. • Raju TNK, Higgins RD, Stark AR, Leveno K. 2006. Optimizing care and outcome for late preterm (near-term) infants: a summary of the workshop sponsored by the National Institute of Child Health and Human Development. Pediatr 118, 1207-1214. • Shapiro-Mendoza C, Tomashek KM, Kotelchuck M. et al., 2006. Risk factors for neonatal morbidity and mortality among “healthy” later preterm newborns. Semin Perinatol, 30, 54-60. • Tomashek KM, Shapiro-Mendoza CK, Weiss J et al. 2006. Early discharge among later preterm and term newborns and risk of neonatal morbidity. Semin Perinatol 30, 61-68.