Neonatal spasms

Neonatal convulsions are clinically defined as paroxysmal alterations of neurological functions - behavior, motor and vegetative functions. Epidemiologically, the dependence on gestational age is proven - neonatal convulsions occur in up to 20% of premature babies, on the contrary, they affect only 0.5% of mature newborns. About 90% of seizures occur in the first two days of life. It can be clinically significant paroxysms of tonic-clonic convulsions, but often the clinical picture is discrete and includes myoclonus, apnea, nystagmus or increased salivation.

Etiology

 * in terms of timing, cramps in the first 120 minutes after birth occur most often due to VVV, withdrawal syndrome, hypoglycemia:
 * 1) central causes,
 * 2) * perinatal brain damage – trauma, intracranial hemorrhage, brain edema, hypoxia,
 * 3) * congenital CNS defects – congenital hydrocephalus, cerebral dysgenesis, genetic causes,
 * 4) * transplacental infection of the CNS – CMV, toxoplasmosis,
 * 5) * febrile convulsions (typically after newborn age, at the earliest from 3 months ),
 * 6) metabolic causes,
 * 7) * hypoglycemia,
 * 8) ** damage to the brain stem – asphyxia, bleeding,
 * 9) ** diabetic fetopathy,
 * 10) ** lack of glycogen – immaturity,
 * 11) ** increased need for glucose – sepsis,
 * 12) ** primary disorder of carbohydrate metabolism,
 * 13) ** primary disorder of AMK metabolism,
 * 14) ** primary disorder of fatty acid oxidation,
 * 15) * hypocalcemia,
 * 16) ** damage to the brain stem – asphyxia, bleeding,
 * 17) ** hypoparathyroidism,
 * 18) ** hypomagnesemia,
 * 19) ** hyperphosphatemia,
 * 20) * lack of pyridoxine – vitamin B6 dependent convulsions (genetically conditioned increased need for vit. B6, convulsions appear both in the first hours of life and also on the 4-5th day after birth, disappear after administration of high doses of vit. B6, disappear again after omission appear)
 * 21) * hypo/hypernatremia,
 * 22) * hyperbilirubinemia,
 * 23) * MAc,
 * 24) * hereditary metabolic disorders,
 * 25) infection,
 * 26) * STORCH,
 * 27) * sepsis,
 * 28) * meningitis,
 * 29) * encephalitis,
 * 30) other,
 * 31) * polycythemia,
 * 32) * core jaundice,
 * 33) * abstinence syndrome.

Classification of neonatal seizures based on clinical picture

 * Basically, we distinguish 2 types of seizure movements: tonus = stiffening and clonus = jerking.

Subtle spasms

 * These are paroxysmal deviations in the newborn's behavior in motor and vegetative manifestations, which are neither purely tonic, nor clonic, nor myoclonic,
 * represent about 50% of newborn seizures, most often in newborns with low birth weight,
 * manifested as horizontal deviation of the eyeballs, twitching of the eyes, repeated blinking, tremor of the eyelids, salivation, yawning, grimacing, apnea,
 * limb movements may resemble rowing, boxing, cycling,
 * on EEG multifocal repetitive sharp waves are present, predilectionally temporally.

Multifocal clonic convulsions

 * They start on one or both limbs and uncoordinatedly move to other parts of the body.

Focal clonic convulsions

 * Rhythmic twitches of muscle groups, the fast phase alternates with the slow,
 * are localized and not associated with unconsciousness,
 * do not occur before the age of 37,
 * unlike tremor, clonic jerks are more pronounced and irregular.

Tonic convulsions

 * Often as a generalized extension of HK and DK → resemble Decerebration Posture,
 * breathing is raspy, eyes turn to the side.

Myoclonic seizures

 * Fast isolated twitches of predilection flexor muscle groups,
 * myoclonus may be isolated or repeated.

hyperexcitability, i.e. non-convulsive manifestations - jitteriness

 * Abnormal eye gaze and bulbar movements are absent,
 * it is possible to provoke a convulsive manifestation by an external stimulus,
 * non-convulsive phenomena have a rhythmic character (epi-convulsions have a fast and slow component),
 * absence of vegetative changes,
 * stopping movement by passive flexion,
 * normal US of the brain, normal EEG and physiological neurological findings.

Diagnostics

 * Anamnesis,
 * mother's medical history: drugs, nutrition, DM;
 * birth history: asphyxia, trauma;
 * physical examination, evaluation of clinical manifestations;
 * laboratory examination:
 * hematological examination and hemocoagulation;
 * biochemistry: blood glucose, ions (especially calcium), urea, bilirubin and liver tests, ammonia, lactate, ABR;
 * inflammatory markers + culture;
 * liquor;
 * examination for sepsis/meningitis – blood culture, lumbar puncture;
 * toxicological examination;
 * metabolic screening;
 * neurological and ophthalmological examination;
 * imaging methods: ultrasound of the brain through the large fontanelle, EEG, CT, possibly MRI, EKG, eye examination;
 * reaction to vitamin B6.

Differential diagnosis of neonatal convulsions according to etiology

 * Stigmatization of the newborn → congenital CNS dysgenesis, genetic syndromes, DMP,
 * trauma (LP, ultrasound, CT, MRI, neurological examination) → intracranial bleeding, brain edema, contusio cerebri,
 * infection (LP, inflammatory markers, culture, IgM, neurological examination) → meningitis, meningoencephalitis, sepsis,
 * perinatal asphyxia (Astrup, chest X-ray) → RDS, HIE,
 * VCC (Astrup, EKG, ECHO, chest X-ray),
 * abnormalities of the internal environment (gly, Na, Ca, Ca ioniz., Mg, pyridoxine) → imbalance of the internal environment,
 * polyglobulia (Hb, Htk),
 * abnormalities of amino acids and organic acids, MAC → DPM,
 * abuse of medicines and drugs in the mother → abstinence syndrome,
 * increased urea, creatinine, MAc → renal failure,
 * normal biochemistry, inflammatory markers and imaging methods → benign familial neonatal convulsions, convulsions of unclear etiology.

Therapy
Phenobarbital Diazepam
 * Ensure basic vital functions – ventilation, circulation, thermoneutral environment,
 * correction of the internal environment,
 * 10% glucose 2 ml/kg i.v. as a bolus followed by 5 ml/kg/hour,
 * 10% calcium gluconicum' 2 ml/kg i.v. within 10 min. under ECG control, then continuously or every 6 hours up to a total daily dose of 5 ml/kg,
 * 10% MgSO4 1 ml/kg during 10 min. i.v., then 0.2 ml/kg every 6 hours,
 * vitamin B6' (pyridoxine') in pyridoxine-dependent convulsions (therapeutically 50–100 mg i.v., preventive substitution approx. 10 mg/kg/day p.o.);
 * anticonvulsants':
 * is the drug of choice in neonatology,
 * doses: 15–20 mg/kg i.v. within 15 minutes, doses of 30–40 mg/kg are also possible, but only with ensured ventilation,
 * daily maintenance dose is 5 mg/kg/d,
 * necessary monitoring of cardiovascular functions → risk of hypotension and monitoring of serum levels.
 * Phenytoin
 * if there is no therapeutic response to phenobarbital,
 * dose: 15–20 mg/kg i.v. at a rate of 0.5–1 mg/kg/min,
 * daily maintenance dose is 5 mg/kg/d,
 * risk of arrhythmia and hypotension, necessary monitoring of serum levels.
 * dose: 0.1–0.3–0.5 mg/kg i.v. slowly to a total dose of 1 mg/kg,
 * has a rapid onset of therapeutic effect, the anticonvulsant half-life is on the order of minutes,
 * with a rapid bolus of higher doses there is a risk of apnea,
 * should not be administered to children with severe jaundice, as it increases the risk of core jaundice.

Source

 * HAVRÁNEK, Jiří: Newborn convulsions;