Hyporesponsive newborn
Introduction
Introduction to low neonatal response Decreeded responsiveness is a group of clinical symptoms that include a certain degree of disturbance of consciousness, decreased muscle tone, decreased physical activity, weak crying and weakness of sucking. Newborns not only show low response in central nervous system diseases, but other manifestations such as severe infection, shock, dehydration, acidosis, metabolic disorders, anemia, hypothermia and respiratory failure. Low clinical response is often used to determine the severity of various diseases. basic knowledge The proportion of sickness: 0.01% Susceptible population: newborn Mode of infection: non-infectious Complications: subarachnoid hemorrhage, sepsis, respiratory failure, shock
Cause
Neonatal reaction low cause
(1) Causes of the disease
Hypoxic ischemic encephalopathy, infection (40%):
Hypoxic ischemic encephalopathy after perinatal asphyxia is the most common cause of low early neonatal response. Sepsis infection can occur in the uterus, at the time of delivery or after childbirth. Premature babies can only show a low response, and the full-term infants have a low response in purulent meningitis, suggesting aggravation.
Respiratory failure hypoglycemia (27%):
When the newborn is hypoxic, it quickly enters a state of inhibition, and the reaction is low. When hypoglycemia occurs in small for gestational age and premature infants, it is often the first to show a low response, and sometimes the lower response becomes the only symptom.
Drugs (15%):
Mothers used antihypertensive drugs or anesthetics before delivery, such as pregnancy-induced hypertension mothers before delivery, with a large amount of magnesium sulfate intravenous infusion, infants can develop hypermagnesemia with low response, even respiratory inhibition; mother before delivery Anesthetics such as pethidine within 2 hours not only make newborns prone to primary asphyxia, but also show low response after birth.
Other (10%):
It is generally considered that when the body temperature is lower than 35 ° C, the reaction is sluggish, and it is in a semi-coma state below 33 ° C. Many diseases in the neonatal period such as dehydration acidosis, cardiac insufficiency, shock, anemia, intracranial hemorrhage, 21-trisomy syndrome and acute renal failure can all show low response.
(two) pathogenesis
1. Examination of neonatal arousal state: neonatal nervous system is immature, central nervous system is imperfect, and it is very different from adult. It is usually used for neurological examination in children and adults. It is not suitable for newborns. When neonatal examination of nerve reflex, it must be noted that infants of different gestational ages may have very different responses to external stimuli. Clinically used neurological reactions and neuroreflex examinations are one of the methods for gestational age assessment.
In the first few days after birth, the newborn is sleeping for about 20 hours every day. When making a neurological reaction check for a newborn, the baby should be awakened first. The most common way to wake up the newborn is to gently shake the baby's chest with the index finger and thumb. Bright light and elastic sole can also be used to wake up the baby. The so-called awakening refers to the opening of the eyes, the movement of the head and limbs, the facial expression movement or crying. It should be noted that the movement of the limb does not mean that the cerebral cortex responds, for example to the baby's sole. A painful stimulus, the lower limbs can be flexed and recovered, this is only spinal cord reflex. The so-called cerebral cortex awakening should include facial expression and/or systemic exercise. The premature infants with gestational age below 28 weeks have no arousal reaction, and the limbs have almost no tension; 28-30 Weekly premature infants have awakening reaction, but the limb tension is very poor, the smaller the gestational age, the shorter the duration of the awakening state. When examining the reaction state for newborns, especially premature infants, the above physiological characteristics must be paid attention to.
2. Assessing the infant's response level: The awakening state of the newborn is closely related to the assessment of the infant's response level. Brazelton divides the awakening state of the newborn's physiological condition into the following six states according to the behavioral performance.
(1) Deep sleep: Close your eyes, breathing regularly, no movements in your limbs and trunk, and it will be delayed when you give strong stimulation, and it is not easy to change to another state.
(2) light sleep (rapid eye movement sleep): the eyelids are closed, the eyeballs rotate rapidly, the breathing is irregular, and it is easy to wake up with strong stimulation, and it is easy to change to another state.
(3) Drowsiness: The eyes are opened or closed, and the limbs and trunks are less and short-lived.
(4) Quiet awakening: the eyes open, the eyeball responds to external stimuli, and the limbs have less activity.
(5) Activity awakening: the eyes are open and the limbs are active and powerful.
(6) crying: the cries are powerful and it is not easy to stop the crying.
In different awakening states, the neonatal response level is also different. When performing a neurological reaction check for a newborn, it is best to perform it in a quiet or active awakening state. Gently swing the baby or shake the chest with your fingers to wake up the baby to keep it. The most appropriate state of awakening, if performed in a deep sleep state, will be erroneously judged as non-response or reduced in activity. The ambient temperature during the test should be maintained at 27 to 30 ° C to prevent excessive temperature or cold irritation from affecting the test results.
Prevention
Neonatal response prevention
1. Do a good job in pregnancy and perinatal care to avoid premature birth, birth injury, suffocation.
2. Provide a good environment and clean with appropriate room temperature and humidity, the general delivery room and baby room temperature is best around 24 ° C, the neonatal room should strictly implement the disinfection and isolation system to provide a good environment and clean for newborns The tools to eliminate all kinds of cross-infection opportunities.
Complication
Neonatal response to low complications Complications, brain, subarachnoid hemorrhage, sepsis, respiratory failure, shock
Depending on the primary disease, there are different complications, such as hypoxic ischemic encephalopathy with subarachnoid hemorrhage or intraparenchymal hemorrhage; central nervous system infection and sepsis, if the skin color is pale, limbs are cool, skin capillaries If the refilling time is prolonged and the heart sound is low and blunt, etc., it should be considered to combine shock. Because of the low response, it is often a group of clinical manifestations, and the condition is heavier or the disease progresses. If the condition cannot be effectively controlled, various complications are likely to occur. Examination of children with low response should focus on respiratory failure, circulatory failure, shock, high fever and hypothermia, and neurological examinations.
Symptom
Neonatal reaction low symptoms Common symptoms Responsive, irritated, restless, drowsiness, dysphagia, Moro reaction, slow sputum reflex, disappearance, cold, coma, weakness, dehydration
Newborns can show low response in central nervous system diseases and other serious infections such as shock, dehydration, acidosis, metabolic disorders, anemia, hypothermia and respiratory failure.
1. Hypoxic-ischemic encephalopathy: It is often irritated on the first day after birth. After 2 to 3 days, the reaction is gradually low, and there are disturbances such as lethargy, dullness and shallow coma. The muscles of the extremities are reduced, and the upper limbs are more obvious than the lower limbs. When doing the pulling reaction, the head sag backwards at a 90° angle to the trunk, hug the reflection, and the sucking reflex is weakened or disappeared, often accompanied by convulsions and increased intracranial pressure, often with cerebral edema, severe cases with subarachnoid hemorrhage or brain Substantial bleeding.
2. Septicemia: often with low response, refusal is the first symptom, no fever or even body temperature, premature babies are more common, often accompanied by jaundice, rash, abdominal distension and enlarged liver and spleen, skin color can appear Pale, cold limbs, skin capillaries refilling time and heart sounds low blunt and other shock performance.
3. Respiratory failure: When the newborn is hypoxic, it is different from the infant. It does not show irritability or even convulsions. Newborns, especially premature infants, quickly enter a state of inhibition, showing impotence, low response, decreased muscle tone, slowing of breathing, and even appearing. Respiratory rhythm is not uniform or apnea. In the case of severe type II respiratory failure, the child's response is even worse. Although oxygen can not improve the response and improve breathing, a respirator is required for mechanical ventilation.
4. Hypothermia: When the body temperature is below 35 °C, the reaction is slow, and it is semi-conscious under 33 °C. Due to the cold stimulation, the heat preservation is not enough to cause the body temperature to drop and the reaction is slow. After the rewarming, the reaction is better with the increase of body temperature. Due to the aggravation of the primary disease, the decrease in body temperature due to decreased feeding and heat production, causing unresponsiveness, often characterized by other primary diseases, such as neonatal pneumonia, neonatal sepsis and so on.
5. Hypoglycemia: low performance response, history of under-feeding or asphyxia, should consider whether there is hypoglycemia.
6. Central nervous system infection: Full-term neonates often show irritation in the early stage of purulent meningitis. Allergic to irritation, the lesion progresses to a certain extent, and the reaction may be low, suggesting that the condition is increased, and the premature babies may not be irritated. Only show low response, often accompanied by convulsions, anterior hernia and other infection symptoms, lumbar puncture can be diagnosed.
7. Drugs: Mothers used antihypertensive drugs or anesthetics before delivery, such as magnesium sulfate, paclitaxel, etc., so that newborns are prone to primary asphyxia, and postoperative performance is low, muscle tone is weak and breathing is weak, and even breathing Suppressed.
8. Others: Many diseases in the neonatal period such as dehydration acidosis, cardiac insufficiency, shock, anemia, intracranial hemorrhage, 21-trisomy syndrome and acute renal failure can all show low response.
Examine
Low neonatal response
Peripheral leukocytosis or decreased in neonatal sepsis, increased rod-shaped nucleus, decreased platelet count, increased C-reactive protein, increased bilirubin, positive blood culture is helpful in the diagnosis of respiratory failure, children with hypoxic ischemic encephalopathy, Blood gas analysis includes hypoxemia, hypercapnia, respiratory or metabolic acidosis, severe type II respiratory failure, PaCO2 up to 9.3 kPa (70 mmHg), blood glucose monitoring contributes to the diagnosis of hypoglycemia, central nervous system Infections such as purulent meningitis, lumbar puncture can be diagnosed, mothers with magnesium sulfate to infants with hypermagnesemia, blood magnesium > 1.75mmol / L (3.5mEq / L); when acute renal failure occurs, there are urine routine and A series of changes in blood biochemistry, etc., are not repeated.
Hypoxic ischemic encephalopathy often has abnormal changes in EEG. Brain CT and brain B-ultrasound can be seen in cerebral edema, subarachnoid hemorrhage or intraparenchymal hemorrhage. If necessary, X-ray examination, electrocardiogram, brain display should be selected according to need. Like techniques such as magnetic resonance imaging (MRI), camphor scan, CT, Doppler intracranial ultrasound and brainstem evoked potentials.
Diagnosis
Neonatal response low diagnosis and identification
Diagnostic criteria
If the newborn has a low response, first determine the degree of low response, then check the accompanying symptoms, do the necessary auxiliary examination, and determine the primary disease as soon as possible. The following items can be used as a reference.
1. Consciousness disorder The method of detecting neonatal disturbance of consciousness is to stimulate the newborn, including pain stimuli, to observe the response and the degree of response. The stimulation method can be used to gently shake the chest, and the finger can be used to rebound the foot. If there is no reaction, acupuncture can be used. As a painful stimulus, Fenichel divides the neonatal disturbance into four states:
(1) Drowsiness: It is easy to wake up, but it is not easy to maintain an awake state.
(2) retarded: can be awakened with non-painful stimuli, but wakes up very late, and is not fully awake, can not maintain awakening state.
(3) Light coma (sleeping): Only painful stimulation can wake up.
(4) Coma: pain stimulation can not wake up.
2. Muscle hypotonia Neonatal hypotonia can be a symptom of the nervous system or muscle lesions, and is also a manifestation of inhibition of the central nervous system in many severe systemic diseases. Muscle hypotonia is manifested as both lower extremity abduction, arms It is soft, the range of elbow and knee joints is increased, and there is no resistance when the limbs are passively moved. When pulling the baby's hands, the baby's hands hang from the supine position to the sitting position, and the head can hang backwards, and can not keep the line with the torso for a few seconds. When standing upright, the head can not be vertical, the limbs are soft and shaken; when the level is lifted, the head and limbs are weak and weak, and the neonatal muscle tension is often accompanied by weak crying, sucking weakness, difficulty in swallowing, and autonomous movement is significantly reduced.
3. Physical examination focuses on the ability to maintain life and accompanying symptoms. Vital signs such as body temperature, heart rate, respiration and blood pressure should be recorded in a timely manner. Nervous system examination includes head circumference, cardia pressure, presence or absence of convulsions, respiratory rhythm, eye movement, pupil The size and response to light, as well as the original reflex should be examined in detail. If necessary, check the fundus for disc edema and fundus hemorrhage. The examination of children with low response should focus on respiratory failure, circulatory failure, shock, hyperthermia and body temperature. Not rising, as well as nervous system examinations.
Differential diagnosis
When the various diseases in the neonatal period progress to a certain extent, there will be almost low response. The medical history should be consulted, combined with clinical symptoms, signs and corresponding laboratories, auxiliary examinations, and clear diagnosis and differential diagnosis.
Central nervous system disease
(1) central nervous system infection: neonatal suppurative meningitis has a low response, suggesting that the disease is weight-increased, often accompanied by convulsions, anterior hernia and other infection symptoms, lumbar puncture can be diagnosed.
(2) Hypoxic ischemic encephalopathy: mostly full-term infants, with a history of intrauterine distress and severe asphyxia; first manifestation of irritation, subsequent low response, weakened or disappeared physiological reflexes, often accompanied by convulsions and increased intracranial pressure EEG, brain CT and brain B-ultrasound can help differential diagnosis.
2. Identification of hypothermia: due to cold stimulation, insufficient heat preservation, the body temperature is lowered and the child's response is low. After rewarming treatment, with the recovery of body temperature, the response is better; if the primary disease is caused by hypothermia Low response, common severe primary diseases and complications, such as neonatal infectious diseases, often show low response as the disease progresses.
(1) Neonatal scleredema: refers to the hardening of the skin and subcutaneous fat caused by various reasons in the neonatal period, accompanied by edema, clinical syndrome of hypothermia, and simply caused by cold, also known as neonatal cold injury Signs, severe cases combined with multiple organ dysfunction, clinical features are not elevated body temperature, skin swelling and multi-system function damage.
(2) neonatal sepsis: the biggest clinical feature is the lack of characteristic features, often with low response, refusal as the first symptom, plus history of intrauterine infection, intrapartum infection or postpartum infection, laboratory blood test Positive, peripheral blood leukopenia, decreased platelet count, C-reactive protein increased significantly, helpful for diagnosis.
(3) neonatal pneumonia: poor general condition, low response, weak crying, refusal of milk, milking and foaming at the mouth, shallow breathing, irregular, etc., rapid changes in the condition, prone to respiratory failure, heart failure life threatening.
3. Hypoglycemia: hypoglycemia caused by various causes (see neonatal hypoglycemia) is less than gestational age and hypoglycemia in premature infants. It is often the first to show low response, sometimes low response becomes the only symptom, combined with medical history, after birth. There is a history of insufficient eating or asphyxia within 3 days, and clinical manifestations and blood glucose monitoring can be diagnosed.
4. Drug-induced: the mother used antihypertensive drugs before delivery, the baby's low response after birth, combined with infant blood magnesium>1.75mmol / L (3.5mEq / L) can be diagnosed; mothers within 2 hours before delivery Anesthetics such as pyridine, which have suffocation at birth and low postnatal response, can be diagnosed.
