physiologic responses of the newborn to birth Flashcards
(34 cards)
initiation of breathing
the first breath of life is in response to mechanical and reabsorptive, chemical, thermal and sensory changes assoc w/birth initiates the serial opening of the aveoli
creating the change from intrauterine life to extra uterine life
Initiating of respiration in the newborn
- production of lung fluid diminishes 2-4 days before labor
- 80-100ml remain in the passageway of a full term newborn
- during birth, fetal chest is compressed and squeezes fluid
- some fluid is reabsorbed withing 2-3 days
mechanical process
- as the fetus experiences labor there is a fetal gasp and active exhalation initiates the removal of fluid from the lungs
- after the first inspiration the newborn exhales, with crying against a partially closed glottis, creating positive intrathoracic pressure
- the high pressure distributes the inspired air throughout the alveoli and begins functional capacity
- lung expansion helps the remaining lung fluid into the interstitial fluid
- most of the lung fluid is reabsorbed in 2-24 hrs
chemical stimuli
- first breath is inspiratory gasp: triggered by increased PCO2 and decreased ph and PO2
- changes trigger aortic and carotid chemorecepters: trigger brain’s respiratory center
- natural result of a normal vaginal birth
thermal stimuli
*significant decrease in environmental temp after birth
stimulates skin nerve ending
newborn response w/rhythmic resp.
*excessive cooling may lead to profound depression of cold stress
*98.6 to 70-75 degrees
sensory stimuli
*intrauterine life
*dark
*sound dampened
*fluid filled environment
*weightless
*newborn experiences
*light
*sound
*effects of gravity
*abundance of tactile, auditory, and visual
stimuli of birth
characteristics of newborn of resp
- newborns are nose breathers-nose is primary route of air entry (due to the anatomy of the epiglottis and soft palate)
- nose and throat must be patient
- immediately after birth RR=60-70 for first 2hrs
- beware of < or > of resp rate=resp distress
onset of resp stimulates cardio changes
*as air enters the lungs, O2 content rises in alveoli and stimulates relaxation of pulmonary arteries
patent ductus arteriosus closes
- with increased oxygenated pulmonary blood flow and loss of placenta, systemic blood flow increases, foramen ovale closes and PDA begins to close
- leads to decrease in pulmonary vascular resistance
- allows complete vascular flow to lungs
characteristics of cardiac function
- HR-avg resting rate- 100-160 bpm
- apical rate for 1 min
- check peripheral pulses
- BP-HIGHEST AFTER BIRTH -LOWEST 3 HRS AFTER BIRTH
BLOOD VOLUME
- BLOOD VOLUME OF TERM INFANT ESTIMATED TO BE 80 ML/KG OF BODY WEIGHT
- NEONATAL RBC = LIFESPAN 60-80 DAYS
- AVERAGE NEWBORN WT. 7LBS 8 OZ
NORMAL TERM NEWBORN CORD BLOOD VALUES
*HEMOGLOBIN 14-20 G/DL
*HEMATOCRIT 43-63%4
*WBC 10,000-30000/MM3
*WBC DIFFERENTIAL
NEUTROPHILS 40-80%
LYMPHOCYTES 20-40%
MONOCYTES 3-10%
*PLATELETS 150000-350000/MM3
*RETICUTOCYES 3-7%
*BLOOD VOLUME 82.3ML/KG (3RD
DAY AFTER
EARLY CORD
CLAMPING
92.6ML/KG (3RD
DAY AFTER
DELAYED
CORD CLAMP
*SODIUM 129-144
*POTASSIUM 3.4-9.9
*CHLORIDE 103-111
*BICARB 18-23
*CARBON DIOXIDE 13-29
*CALCIUM 8.2-111
*GLUCOSE 45-96
*TOTAL PROTEIN 4.8-7.3
HEAT LOSS IS CREATED
- EVAPORATION (WET W/AMNIOTIC FLUID)
- CONVECTION (LOSS OF HEAT FROM WARM BODY SURFACES TO COOLER AIR CURRENTS)
- RADIATION (COOLER OBJECTS NEAR INCUBATOR)
- CONDUCTION (COLD STETHOSCOPE, COLD HANDS)
THERMOGENESIS
- NONSHIVERING THERMOGENESIS
- BROWN ADIPOSE TISSUE (BAT) PROVIDES HEAT. PROMOTES RAPID METABOLISM, HEAT GENERATION , HEAT TRANSFER TO THE PERIPHERAL CIRCULATION
*FOUND IN MIDSCAPULAR AREA, AROUND
NECK, AXILLAS
*IF NEWBORN SHIVERS, METABOLIC RATE
DOUBLES
*INCREASED MUSCLE ACTIVITY
THERMOGENESIS
*BAT IS PRIMARY SOURCE OF HEAT IN HYPO-
THERMIC NEWBORN
*APPEARS IN FETUS AT 26-30 WEEKS
*INCREASED UNTIL 2-5 WEEKS AFTER BIRTH
CONJUGATION OF BILIRUBIN
THE NEWBORNS LIVER PLAYS A SIGNIFICANT ROLE IN IRON STORAGE, CARB METABOLISM,
CONJUGATION OF BILIRUBIN AND COAGULATION
PHYSIOLOGIC JAUNDICE
*OCCURS IN 50% OF TERM AND 80% OF PRE- TERM NEWBORNS *CAUSED BY ACCELERATED DESTRUCTION OF FETAL RBC'S AND INCREASED REABSORP- TION OF BILLIRUBIN BY LIVER/NORMAL. *PEAKS IN 3-5 DAYS IN THE FULL TERM BABY
PHYSIOLOGICAL (NORMAL) JAUNDICE
*OCCURS IN MOST NEWBORNS
*DUE TO IMMATURITY OF THE BABY’S LIVER
WHICH LEADS TO SLOW PROCESSING OF
BILLIRUBIN
*APPEARS 2-4 DAYS OF AGE
*DISAPPEARS 1-2 WKS OF AGE
JAUNDICE OF PREMATURITY
*OCCURS FREQUENTLY IN PREMIES
*LESS READY TO EXCRETE BILIRUBIN
EFFECTIVELY
BREASTFEEDING JAUNDICE
*OCCURS WHEN BABY NOT GETTING ENOUGH BREAST MILK (DIFFICULTY W/BREASTFEEDING OR MOMS MILK ISN'T IN YET *NOT CAUSED BY MOMS MILK/BABY NOT GETTING ENOUGH
BREAST MILK JAUNDICE
*CAUSED BY THE MOMS BREAST MILK CAN HAVE SUBSTANCES THAT CAUSE THE BILIRUBIN LEVEL TO RISE *IT CAN PREVENT THE EXCRETION OF BILIRUBIN THROUGH THE INTESTINES *STARTS 3-5 DAYS AND SLOWLY IMPROVES OVER 3-12 WKS. TEMP CESSATION IS ADVISED UNTIL LEVEL DECREASE
NURSING CARE FOR NEWBORNS
- KEEP BABY WELL HYDRATED
- KEEP BABY WARM
- MONITOR STOOLS
- ENCOURAGE EARLY FEEDING
ELIMINATION
*MECONIUM IS FORMED IN UTERO
*NEWBORN PASSES MECONIUM WITHIN 48HRS
FREQUENCY OF BOWEL MOVEMENT VARIES
*1 STOOL EVERY 2-3 DAYS OR UP TO 10 PER
DAY
*BROWN/GREEN ABNORMAL/LOOK FOR
DEHYDRATION
VOIDING
*93% VOID BY 24 HRS AFTER BIRTH AND 100%
VOID BY 48 HRS AFTER BIRTH
*INITIAL BLADDER VOLUME IS 6-44 ML URINE
*IF NEWBORN DOES NOT VOID WITHIN 48 HRS,
NURSE SHOULD ASSESS ADEQUACY OF
FLUID INTAKE, BLADDER DISTENTION
RESTLESSNESS, AND SYMPTOMS OF PAIN
