Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Asphyxia”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25Linked to original sources

Heart size in newborn infants with birth asphyxia.

Cardiomegaly is believed to be an important and relatively common radiographic finding in infants asphyxiated at birth. However, the true incidence of cardiomegaly in such infants has not been previously assessed. Accordingly, heart size was estimated using the cardiothoracic ratio (CTR) in 67 consecutive neonates with birth asphyxia (Apgar score below 6 at 1 and 5 min). The average CTR on the first postnatal film was 52.8%, significantly higher than that of unasphyxiated infants published previously. Subsequent CTR values did not differ significantly from the initial value. Of the 67 patients studied, 13 (19%) had significant cardiomegaly (CTR more than 2 SD above normal). Of these, 10 had conditions other than asphyxia that probably contributed to the cardiomegaly observed. Although relative heart enlargement is common in asphyxiated infants, absolute cardiomegaly is relatively uncommon, and in such infants causes other than asphyxia should be sought.

Asphyxia Neonatorum↗

Cerebral artery Doppler ultrasonography for prediction of outcome after perinatal asphyxia.

Perinatal asphyxia is the most common cause of neurologic injury and neurodevelopmental delay. The signs of injury are nonspecific at birth, and most indicators take hours to days before they become manifest. Early recognition of the injury is important in guiding management during those critical first days of life. Over a five-year period, we investigated 16 term neonates with a history of asphyxia on the first day of life who demonstrated on intracranial Doppler sonography cerebral vessel high diastolic flow with a resistive index below 60. Two infants died and one was lost to follow-up. Three of the remaining 13 patients were normal at 8 months to 1 year follow-up. The remaining 10 patients had severe neurodevelopmental delay with profound handicaps at follow-up periods from 3 months to 32 months. This study has confirmed earlier reports that in the first days of life, a very low resistive index combined with history of asphyxia is associated with an adverse outcome and may be considered one of the earliest markers for poor neurodevelopmental outcome. Only 50% of these patients demonstrated abnormal sonographic imaging.

Asphyxia Neonatorum↗

Reproducibility and accuracy of MR imaging of the brain after severe birth asphyxia.

BACKGROUND AND PURPOSE: MR imaging of the brain can be used to detect cerebral damage after suspected hypoxic-ischemic injury. This study examines the reproducibility and accuracy of MR imaging soon after severe birth asphyxia. METHODS: During a 48-month period, full-term newborn neonates, who died within the first week as a result of severe hypoxic ischemic encephalopathy, were included in the study if they had undergone early (<5 days old) MR imaging and postmortem neuropathologic studies. Two trained observers assessed reproducibility by examining multiple brain regions independently with current criteria and then defining and applying improved criteria. Accuracy of MR findings was tested by comparing the brain regions about which the two imaging raters agreed to those regions about which the two pathologists agreed. RESULTS: Eight neonates, with a median gestational age of 40 weeks (range, 38-40 weeks) and who suffered severe birth asphyxia, were included in the study. In the reproducibility study, MR imaging agreement was moderate when current criteria were used (k = .44). Using the improved criteria, agreement increased considerably (k = .62). Much of this improvement was due to limiting the analyses to the posterior limb of the internal capsule, thalamus, parietal cortex, hippocampus, and medulla. The posterior limb of the internal capsule was the most reliable region analyzed. MR imaging agreement was similar to that achieved by two experienced pathologists reviewing the histologic sections (k = .66). In the accuracy study, MR imaging abnormality was predictive of pathologic abnormality with a sensitivity of .79 and a positive predictive value of 1.0. The predictive value of a single MR imaging abnormality was .79 (95% confidence interval, .61-.96). CONCLUSION: Criteria that provide substantial reproducibility and accuracy for the interpretation of MR imaging findings very early after birth asphyxia can be derived.

Asphyxia Neonatorum↗

Risk factors for perinatal asphyxia at Queen Elizabeth Central Hospital, Malawi.

The aim of the study was to identify maternal risk factors for perinatal asphyxia in Malawi. Records of 100 mothers who delivered neonates with Apgar scores less than 6 at 5 minutes of birth during March to September 1998 were analyzed. The majority of the mothers were primigravidas (79%) and were within the normal childbearing ages of 20 to 34 years (61.2%). Sixty-one percent of the mothers started antenatal care at 20 to 28 weeks' gestation. Sixty-five percent of the mothers developed obstetric and medical problems that contributed to perinatal asphyxia, and of these, 12 mothers (18.5%) had more than one problem. The problems were premature labor and delivery (21%), preeclampsia (10%), cephalopelvic disproportion (8%), breech presentation (12%), prolonged second stage (11%), fetal distress (7%), cord prolapse (4%), antepartum hemorrhage (2%), prolonged rupture of membranes (1%), and malaria (1%). Forty-six percent had assisted deliveries, and these were cesarean section (18%), vacuum extraction (14%), breech delivery (12%), and forceps delivery (2%). Eighty-one percent of the neonates were admitted to the neonatal nursery, and of these, 56 neonates (67.1%) developed complications; the most common was hypoxic ischemic encephalopathy (38 neonates; 67.9%). Thirty-three percent of the neonates died within 6 days postdelivery. Morbidity and mortality related to perinatal asphyxia can be reduced if staff are knowledgeable and skilled in basic neonatal resuscitation and necessary equipment is available. Mothers should be encouraged to report early for antepartum and intrapartum care for adequate surveillance. The quality of neonatal care, with a focus on thermoregulation and infection prevention, needs to be improved.

Adolescent↗

EEG evaluation of humaneness of asphyxia and decapitation euthanasia of the laboratory rat.

The relative humaneness of asphyxia and decapitation was objectively evaluated in rats by EEG monitoring. EEG activation (low voltage, fast activity) was considered to indicate discomfort, pain, and affective responses to euthansia. Such activation was present 37.3 plus or minus 7.5 sec after asphyxia and 13.6 plus or minus 4,6 sec after decapitation. Decapitation was also characterized by an immediate large, and relatively long-lasting, ultra-slow voltage, detected by non-polarizable scalp electrodes. Isoelectric activity (death) occurred 69.4 plus or minus 9.9 sec after onset of asphyxia and 27.2 plus or minus 4.4 sec after decapitation.

Action Potentials↗

Effect of asphyxia on non-protein-bound iron and lipid peroxidation in newborn infants.

The effect of asphyxia on iron metabolism and lipid peroxidation in newborn infants with hypoxic-ischemic encephalopathy (HIE) was investigated. Non-protein-bound iron (NPBI) and lipid peroxidation (thiobarbituric-acid-reactive species; TBARS) in plasma and hematological iron indices were measured in 15 healthy newborn infants (mean gestational age 39 04 weeks, SD 1); 15 asphyxiated infants without neurological abnormalities (AS-HIE; mean gestational age 38.8 weeks, SD 0.9); and 15 asphyxiated infants with neurological abnormalities (AS+HIE; mean gestational age 39.75 weeks, SD 1.4). Follow-up was performed at the age of 5 months. It was found that the detectable rates of NPBI in 10 of 15 of the AS-HIE group and 13 of 15 of the AS+HIE group were significantly higher than that of the control group (5 of 15; both p < 0.01). Plasma levels of TBARS in the control (9.20 micromol/L, SD 1.9) and AS-HIE infants (10.13 micromol/L, SD 2.7) were significantly lower than those of the AS+HIE group (13.42 micromol/L, SD 2.8). Serum iron, total iron binding capacity, and transferrin saturation in the AS+HIE group was higher than the corresponding values of the control and AS-HIE groups, although no statistical difference was found among them. At 5 months of age, all control and AS-HIE infants were neurologically normal, whether or not their NPBI was detectable. Of the 12 AS+HIE infants, four (all of whom had detectable NPBI) were neurologically impaired. The average Gross Development Quotient of AS+HIE infants was significantly lower than that of the control or AS-HIE groups (p < 0.01). Results showed that asphyxia could affect iron metabolism and lead to a significant increase in NPBI and lipid peroxidation in newborn infants with HIE, indicating that iron delocalization induced by asphyxia plays a role in the brain injury of asphyxiated infants.

Analysis of Variance↗

Birth asphyxia--analysis of 235 cases.

OBJECTIVE: To look for risk factors leading to birth asphyxia in new borns admitted in a tertiary care unit STUDY DESIGN: Retrospective analysis. SETTING: Neonatal Unit of National Institute of Child Health, Karachi from 1st January, 2001 to 31st August, 2001. PATIENTS AND METHODS: Records of 235 new borns admitted with birth asphyxia during this period were analyzed. Variables studied included antenatal care, period of gestation, place of delivery, mode of delivery, birth weight and age at arrival in the hospital. RESULTS: Majority (71%) of mothers were booked and had antenatal care, similarly most (88%) of the babies were born at term and 75.3% were delivered in maternity homes or hospitals. Caesarian sections were performed in 14% cases and rest were all vaginal deliveries. Fifty seven percent newborns weighed more than 2.5 kg and 22.5% presented to the hospital within 6 hours of birth. CONCLUSION: Birth asphyxia occurring in such a high number of booked cases delivered at term with good weight, reflects the poor perinatal services offered in those maternity homes or hospitals. It is recommended that trained personnel and neonatal resuscitation equipment should be made mandatory in all maternity homes/hospitals.

Asphyxia Neonatorum↗

Pathological approaches to SIDS. I. Special emphasis on the histopathological differences between SIDS and asphyxia.

Histopathological observation was performed to clarify pathological differences of the lung between SIDS and asphyxia. In regard to pulmonary edema, there was no significant difference between SIDS and asphyxia. Occurrences of microemboli in the pulmonary vessels in cases of SIDS showing aspiration of gastric content into the lung, asphyxia and drowning were significantly high, compared with that of SIDS cases without aspiration.

Adolescent↗

Intrapartum asphyxia in term and post term infants.

Many attempts have been made to identify infants at risk of suffering asphyxial brain damage. In a retrospective review of records at the Rotunda Hospital over a five year period all infants who died or suffered seizures, presumed secondary to asphyxia, were compared with the general hospital population. Out of 28,655 deliveries reviewed, there were 13 deaths in infants at or after term associated with perinatal asphyxia, and 32 surviving infants had asphyxial seizures. Seizures were regarded as asphyxial in origin if they occurred in the first forty eight hours of life and were associated with other clinical evidence of asphyxia. The incidence of abnormal presentations, assisted breech deliveries, instrumental deliveries and emergency caesarean sections was all increased in the asphyxial categories compared to the control population. Referral to the fetal assessment unit was associated with a seizure rate of 0.16/1000 live births compared with a rate of 1.4/1000 in the remaining non referred hospital population. Nineteen percent of the infants who seized subsequently developed cerebral palsy. It would appear from our data that referral to the fetal assessment unit and the consequent assignment to "high risk" status is associated with low risk in terms of asphyxial outcome.

Asphyxia Neonatorum↗

Effects of asphyxia on arterial blood pressure, formation of nitric oxide in medulla and blood parameters in the cat.

The rostral ventrolateral medulla (RVLM) plays an important role in the integration of cardiovascular functions. We examined the effect of asphyxia on cardiovascular responses, on sympathetic vertebral nerve activity (VNA) and nitric oxide (NO) formation in the RVLM, on hemodynamics, and on plasma concentrations of catecholamines, blood gas partial pressures and carbohydrate metabolites. Using 16 anesthetized cats we found that the systemic arterial pressure (SAP), VNA, NO formation and the release of plasma catecholamine components of norepinephrine and epinephrine were increased during asphyxia. The onset of NO production was significantly earlier than that of SAP and VNA. The venous partial pressure of O2 decreased, while the partial pressure of CO2 increased. Furthermore, metabolism of glucose and lactate increased, as did the blood concentrations of white and red blood cells, hemoglobin and platelets. Thus, asphyxia increased SAP, VNA and NO formation. It increased the plasma catecholamines, blood gases, carbohydrate metabolites and blood cells.

Animals↗

Mortality and morbidity after intrapartum asphyxia in the preterm fetus.

This matched cohort study examined the significance of intrapartum fetal asphyxia determined biochemically in the preterm newborn in regard to outcome during the first year. Thirty preterm newborns with metabolic acidosis at delivery were compared with 60 preterm newborns, matched for birth weight, with normal blood gas measures. Deaths during the first year were reviewed. Assessment of the surviving children at 1 year corrected age included neurologic examination, Bayley scales, and Uzgiris and Hunt scale to define motor and cognitive development. Seven asphyxiated infants (23%) died during the first year compared with two nonasphyxiated infants (3%), a statistically significant difference (P less than .006). Among the surviving children, the incidence of minor motor and/or cognitive deficits was the same in the two groups. The incidence of major motor and/or cognitive deficits in the group with asphyxia (eight of 30) was significantly greater than in the control group (eight of 60) (P less than .03). These results indicate that intrapartum fetal asphyxia in the preterm newborn is a contributing factor to the mortality and morbidity observed in these children.

Asphyxia Neonatorum↗

[Voluntary apnea of maximum duration as a model of short-term asphyxia in psycho- and electrophysiological studies].

We evaluated the test with arbitrary external respiratory standstill (AEKS) of maximum duration as a model of short-term asphyxia. The experiments were carried out in volunteer students. The level of oxyhemoglobin saturation and tissue oxygen tension that we registered in a group of sportsmen in the course of AEKS of maximum duration demonstrated that asphyxia developed in some of the probationers within 100-120 seconds. Taking into consideration the fact that registration of many psychophysiological and electrophysiological parameters takes place within the interval from several hundreds of milliseconds to several tens of seconds AEKS of maximum duration may be regarded as an adequate model of short-term asphyxia.

Adult↗

[Role of interleukin-1 receptor antagonist in protecting kidney from injury induced by asphyxia in neonatal rats].

OBJECTIVE: To observe the role of recombinant human interleukin-1 receptor antagonist (rhIL-1ra) in protecting kidney from injury induced by asphyxia in neonatal rats. METHODS: Neonatal rats were used as experimental animals. The changes in intrarenal inflammatory response and renal injury were examined in the control group (n=13), and 2, 24 and 48 hours after asphyxia followed by normal saline treatment in those treated with rhIL-1ra. RESULTS: In normal saline group, the white blood cell count, the blood interleukin-1 (IL-1), IL-8, IL-6, nitric oxide (NO), endothelin (ET-1) levels, and the renal coefficient (LRC), the scores of injured tubules of the left kidney were significantly increased at 2 hours (n=10), 24 hours (n=11), and 48 hours (n=10, P<0.05 or P<0.01). Compared with the normal saline group, the levels of the above parameters, except IL-6, were significantly decreased in rhIL-1ra treatment group at the same time points (P<0.05 or P<0.01). Serum IL-6 at 24 hours and 48 hours was also decreased in rhIL-1ra treatment group significantly (P<0.05 or P<0.01). CONCLUSION: The results suggest that rhIL-1ra may protect renal injury after asphyxia via inhibiting intrarenal inflammatory response.

Animals↗

[Assessment of cochlea activity in a group of newborns with central nervous system impairment as an effect of perinatal asphyxia using click-evoked otoacoustic emissions (CEOAEs)].

During adaptation of newborn to extra-uterine environment dramatic changes in functioning in the inner organs and the entire human body is observed. Complicated or premature birth as well as complicated course of a perinatal period may cause reversible or irreversible damage of various tissues, organs or systems, and, consequently, their dysfunction. The most often changes in the central nervous system (CNS) in newborns occurring as an effect of perinatal asphyxia are found to be ischemic-hypoxic encephalopathy (IHE), periventricular leucomalacia (PVL) and intraventricular hemorrhages (IVH). Chronic hypoxia is considered to affect the hearing organ in newborns. Reversible or irreversible changes within the cochlea, brainstem or cortex may result in perceptive hearing losses. The aim of the study was to carry out the objective assessment of the cochlea activity using CEOAEs in neonates with CNS impairment occurring following perinatal asphyxia. To the investigation 16 newborns with IHE, PVL or IVH were included. The control group encompassed the health newborns matched as to the age. Perinatal anamnesis, general pediatric status, results of trans-fontanel ultrasonography and biochemical test results were taken into account in statistical analyses. In all newborns otoscopic examination and CEOAEs after birth and 3 months later were performed. CEOAEs in session 1 were significantly reduced in the investigated group comparing to control babies but 3 months later no differences between groups were observed. The outer hair cells activity in first days of life is reduced in newborns with asphyxia in anamnesis but with time no differences in cochlea development are observed.

Acoustic Stimulation↗

PAF receptor antagonists influence asphyxia-induced changes of the inner ear.

The influence of a transient asphyxia on cochlear potentials, i.e. endolymphatic potential (EP), summating potential (SP) and cochlear microphonics (CM) was investigated in guinea pigs which were injected with two different PAF receptor antagonists before. It could be shown that apafant (WEB 2086) and bepafant (WEB 2170) significantly reduced the asphyxia-induced potential changes compared to controls. The results suggest a mediating role of PAF in the asphyxia model. The impact of the findings for therapeutics is discussed.

Animals↗

Unusual form of accidental mechanical asphyxia.

This brief case report shows an unusual form of accidental atypical strangulation. A 46-year-old male became trapped between the rims of an automatically closing door during his hopeless effort to enter a supermarket at night. The victim's neck was violently pressed by the edges of the automatic door. From external observation we found an incomplete ligature mark and numerous small abrasions in the neck. On autopsy we found typical signs of asphyxia and fractures of the hyoid-laryngeal complex and bruising of the soft tissues of the neck. The subsequent toxicology was negative with the exception of alcohol level. We came to the common conclusion of a double form of mechanical asphyxia - atypical violent strangulation and atypical hanging. The third highly likely contributory factor of death was direct stimulation of the baroreceptor nerve endings in the left carotid sinus and left carotid sheath. In recent literature, there have been presented only a few cases describing this manner of asphyxia and death.

Accidents↗

[The effect of intrapartum and neonatal asphyxia on the cognitive and behavioral development of children].

The present study includes 4 groups of subjects: 30 children with a history of intrapartum asphyxia, 30 children with a history of mild neonatal asphyxia, 15 children with a history of severe but transitory neonatal asphyxia, and 30 children who had normal deliveries. Psychological and neuropsychological assessments were done at 6 years of age. There are no significant difference among 4 groups in IQ, social maturity age, most neuropsychological functions and incidence of attention deficit disorder with hyperactivity. 4 test scores in Halstead-Reitan Battery infer to visual-motor functioning showed backwardness in asphyxiated groups. Behavior problems are more frequently seen in the asphyxiated groups than in the control group.

Asphyxia Neonatorum↗

Perspectives in diving and asphyxia.

Animals vary in their ability to tolerate asphyxia. Among aquatic species, some are well adapted to asphyxia associated with the apnea of their diving behavior. The related mechanisms and their regulation are not unique to aquatic animals, rather they are extensions of similar reactions noted in terrestrial species. Our understanding of asphyxia has grown in large part from research on aquatic mammals and birds and by comparing the responses of these natural breath-holding specialists with those of other animals. Studies in nature and in the laboratory have both contributed to this knowledge. The divers have been shown to rely ultimately on oxygen conservation and enhanced anaerobic reserves, producing a strategic retreat into a hypometabolic state.

Adaptation, Physiological↗