Days Of Oxygen Therapy Research Articles

Oxygen Delivery Through Nasal Cannulae to Preterm Infants: Can Practice Be Improved?

Oxygen delivery through nasal cannulae to convalescent preterm infants is a common but largely unstudied practice. To learn more about current nasal cannula oxygen delivery practices, we examined the variations in oxygen delivery through nasal cannulae among the centers of the Neonatal Research Network, the frequency of prescription of low levels of oxygen, and the success of weaning to room air. We hypothesized that some infants treated with oxygen through nasal cannulae were receiving oxygen levels equivalent to those of room air. This was a descriptive, nested, cohort study of nasal cannula oxygen prescription among 187 infants with birth weights of <1250 g. All infants were studied at a postmenstrual age of 36 weeks, with a timed oxygen reduction challenge to establish their ability to be weaned to room air. The results of this challenge were compared with the fraction of inspired oxygen (FIO2) delivered, calculated as effective FIO2. Infants who maintained oxygen saturation values of > or =90% during oxygen weaning and during a 30-minute period in room air were defined as passing the challenge. Fifty-two infants (27.8%) were receiving oxygen concentrations and flow rates through nasal cannulae that delivered an effective FIO2 of <0.23, of whom 16 were receiving oxygen concentrations and flow rates that delivered an effective FIO2 of 0.21. In addition, 22 infants (11.8%) were prescribed room air through nasal cannulae intentionally. Seventy-two percent of those prescribed an effective FIO2 of <0.23 passed the room air challenge. Prescription of oxygen with combinations of flow rates and oxygen concentrations that delivered a low effective FIO2 was common. We speculate that some of this, including the inadvertent prescription of an effective FIO2 equivalent to that of room air, is related to lack of knowledge of the effective FIO2. Routine calculation of effective FIO2 values may prompt earlier trials of room air and thus reduce unnecessary days of oxygen therapy.

230 Is Cumulative Nutritional Deficit Predictive of Extrauterine Growth Retardation in Very Preterm Aga Infants?

Background/aims: A nutrient deficit is a frequent feature in premature infants and may represent one of the main causes of poor postnatal growth.Methods: AGA infants with GA < 31 weeks admitted to our NICU between 2000 and 2004 were included in the study if they had no major congenital anomalies and were still hospitalized at 34 wks PMA. A metabolizable energy intake of 100 kcal/kg/day and a metabolizable protein intake of 3.0 g/kg/day were assumed to be adequate. Actual intake was subtracted from these reference intakes to calculate daily and cumulative deficit. Extrauterine growth retardation (EUGR) was defined by a weight z score < -1.28 at discharge.Results: Among 174 infants studied, 45(25,9%) had EUGR. They showed lower weight z score at birth (-0.24±0.66 vs 0.25±0.66), higher CRIB score (4.3±3.3 vs 2.6±2.6), more days of oxygen therapy (34.7±45 vs 25.8.6±44) and mechanical ventilation (16.3±18.7 vs 9.9±23.3), more postnatal steroids use (57.8 vs 33.3%), greater cumulative deficit in energy (-83±318 vs +42±219 kcal/kg) and in protein (-14.7±27.4 vs -10.0±16.1g/kg) and a longer length of stay (76.6±21.5 vs 65.3±22.7) than no EUGR infants. In the multiple logistic regression analysis weight z score at birth (OR 0.18 CI95%0.09,0.38), CRIB score (OR 1.21 CI95%1.03,1.42), length of stay (OR 1.03 CI95%1.005,1.05) and cumulative deficit in energy (OR 0.995 CI95%0.992,0.997) were identified as independent predictors of EUGR. Cumulative deficit in energy emerged as one of the independent predictors also for poor growth in length (OR 0.999 CI95%0.998,1.000) and in head circumference (OR 0.997 CI95%0.995,0.999).Conclusion: Cumulative energy deficit is associated to EUGR among very preterm infants; changing current practices to limit this deficit is essential to improve postnatal growth.

Arterial oxygen fluctuation and retinopathy of prematurity in very-low-birth-weight infants.

To determine the influence of arterial oxygen fluctuation on development of threshold ROP. Retrospective study of 231 infants, < or =1500 g birth weight, who were admitted to Arkansas Children's Hospital NICU from January 1993 to June 1995. Fluctuation in partial pressure of dissolved arterial oxygen (PaO(2)) was expressed as coefficient of variation (CoV) for each infant. We investigated the relationship between CoV at three intervals and the risk of developing threshold ROP. The odds ratio (OR) of developing threshold ROP versus prethreshold ROP or less associated with a 10% increase in the CoV during the first 5 days of oxygen therapy was 1.44, and during the first 10 days was 1.51. When analysis was restricted to infants receiving 30 days of therapy, the OR during the first 5 days of therapy was 1.67, during the first 10 days was 1.82, and during days 11-30 was 1.68. Very-low-birth-weight infants experiencing fluctuating PaO(2) are at higher risk of threshold ROP.

Retinopatía del prematuro. Casuística de los años 1995–2001

Retinopathy of prematurity (ROP) is a cause of neurosensorial morbidity. To study the incidence, associated risks factors, treatment, and outcome of ROP in premature infants born at less than 32 weeks in our hospital. We performed a descriptive study of patients born between the January 1, 1995, and December 31, 2001, in Sant Joan de Déu Hospital in Barcelona (Spain) at <= 32 weeks of gestation who survived until their first month of life. An ocular evaluation was performed between weeks 4 and 6 of life and was repeated every 1-2 weeks until retinal vascularization was complete. Ocular sequelae and visual function were evaluated. Bivariate comparison of groups with and without ROP was performed. Of the 324 patients evaluated, 74 presented ROP (22.8 %), of which 63 patients (21.7 %) were classified as stage 1 or 2 and 11 (3.7 %) as stage 3. An inverse correlation between the incidence of retinopathy and weight and gestational age was found. Threshold disease (3 plus) was detected in 9 patients (16 eyes; 3.1 % of the study sample and 12.1 % of the neonates with retinopathy). All of these neonates were treated with laser therapy. Ocular sequelae were mild in 2.7 % of the patients, moderate in 0.6 % and severe in 0.6 %. The visual function (n 236) of infants with ROP (n 74) was altered in 4 patients (1.7 %). Of these, alterations were severe in 2 patients (0.8 %). Bivariate analysis revealed significant differences (p < 0.001) in low birth weight, gestational age, days of oxygen therapy, days of mechanical ventilation, days of antibiotic therapy, and number of blood transfusions. In this study the incidence of ROP was similar to that in other centers. Development of ROP was strongly associated with its various risk factors. Severe stages were not seen above 30 weeks of gestational age. The results of laser therapy were optimal, with fewer alterations in ocular examination and visual function than those estimated in patients without treatment.

Supplemental Oxygen Use in Ischemic Stroke Patients, Does Utilization Correspond to Need for Oxygen Therapy?

P236 Background: In 1994, the American Heart Association Stroke Council stated that there is no data to support routine use of supplemental oxygen in stroke patients. The purpose of this study was to determine the degree of supplemental oxygen use in ischemic stroke and whether patients receiving oxygen met criteria for therapy. Methods: An extensive literature search was performed to generate a comprehensive list of explicit criteria for supplemental oxygen use. When the literature disagreed, criteria were included in the list to overestimate rather than underestimate the justification for oxygen use. A retrospective chart review of 169 consecutive, non-intubated, ischemic stroke patients admitted to a university hospital during calendar year 1998 was performed. Two patients were excluded due to missing data yielding a sample of 167 patients. Data included demographic and co-morbidity information as well as a check of each inpatient day for documentation of any of the explicit criteria for supplemental oxygen use. Results: A total of 167 patient charts were reviewed yielding a total of 600 inpatient days abstracted. Of the 167 patients, 102 (61.1%) received oxygen accounting for 322 patient days. Of the 322 inpatient days that patients received oxygen, 147 (45.6%) met at least one criteria for oxygen utilization. Of the 278 inpatient days that patients did not receive oxygen 69 (24.8%) would have met at least one of the criteria for oxygen use. For the entire population, statistically significant factors associated with patients receiving oxygen included: presence of at least one justifying criteria, increasing age, white race, male gender, history of atrial fibrillation, and a history of hypertension. Conclusion: We developed a comprehensive, literature-based list of criteria for supplemental oxygen therapy that was designed to overestimate rather than underestimate the justification of oxygen utilization. Using this explicit list, only 45.6% of days of oxygen therapy were justified in our ischemic stroke population. This study demonstrates that oxygen therapy is commonly given to ischemic stroke victims without clear indication.

Supplemental Oxygen Use in Ischemic Stroke Patients, Does Utilization Correspond to Need for Oxygen Therapy?

P236 Background: In 1994, the American Heart Association Stroke Council stated that there is no data to support routine use of supplemental oxygen in stroke patients. The purpose of this study was to determine the degree of supplemental oxygen use in ischemic stroke and whether patients receiving oxygen met criteria for therapy. Methods: An extensive literature search was performed to generate a comprehensive list of explicit criteria for supplemental oxygen use. When the literature disagreed, criteria were included in the list to overestimate rather than underestimate the justification for oxygen use. A retrospective chart review of 169 consecutive, non-intubated, ischemic stroke patients admitted to a university hospital during calendar year 1998 was performed. Two patients were excluded due to missing data yielding a sample of 167 patients. Data included demographic and co-morbidity information as well as a check of each inpatient day for documentation of any of the explicit criteria for supplemental oxygen use. Results: A total of 167 patient charts were reviewed yielding a total of 600 inpatient days abstracted. Of the 167 patients, 102 (61.1%) received oxygen accounting for 322 patient days. Of the 322 inpatient days that patients received oxygen, 147 (45.6%) met at least one criteria for oxygen utilization. Of the 278 inpatient days that patients did not receive oxygen 69 (24.8%) would have met at least one of the criteria for oxygen use. For the entire population, statistically significant factors associated with patients receiving oxygen included: presence of at least one justifying criteria, increasing age, white race, male gender, history of atrial fibrillation, and a history of hypertension. Conclusion: We developed a comprehensive, literature-based list of criteria for supplemental oxygen therapy that was designed to overestimate rather than underestimate the justification of oxygen utilization. Using this explicit list, only 45.6% of days of oxygen therapy were justified in our ischemic stroke population. This study demonstrates that oxygen therapy is commonly given to ischemic stroke victims without clear indication.

Response to high frequency jet ventilation may predict the need for extracorporeal membrane oxygenation.

The aim of this study was to determine predictors of response whilst using high frequency jet ventilation (HFJV) for infants in intractable respiratory failure, in order to avoid the utilization of extracorporeal membrane oxygenation (ECMO). We reviewed patient demographics, ventilator parameters, blood gas values, length of oxygen therapy and use of surfactant and outcome, in infants given a 4 h trial of HFJV as the minimum to eliminate those infants where HFJV is used as a bridge to ECMO. The study was carried out in the neonatal intensive care nursery at Kosair Children's Hospital in Louisville, Kentucky, which provides high frequency ventilation and ECMO. Thirty infants who were eligible for ECMO and who met the study criteria were divided into two groups based upon response to HFJV. Twenty two infants responded to HFJV and eight nonresponders required ECMO after a trial of HFJV. Infants responding during HFJV demonstrated a significant decrease in oxygenation index without an escalation of mean airway pressure within 4 h after the initiation of HFJV. These infants had lower birth weights and an increased incidence of respiratory distress syndrome. No statistical differences were found in length of ventilation, days of oxygen therapy or duration of HFJV between the groups. Infants in intractable respiratory failure, who are eligible for extracorporeal membrane oxygenation, should receive a trial of high frequency jet ventilation, especially if the cause is respiratory distress syndrome unresponsive to surfactant therapy. During high frequency jet ventilation, the oxygenation index and mean airway pressure should be monitored serially, since they may predict the need for extracorporeal membrane oxygenation.

Maternal and neonatal morbidity associated with in vitro fertilization

Objective: The purpose of this case-control study was to examine the maternal and neonatal morbidities associated with in vitro fertilization (IVF) in a single large teaching hospital. It was hypothesized that IVF mothers would have more perinatal complications and IVF infants would have higher mortality and morbidity rates than non-IVF control subjects. Methods: One hundred forty-three gestations resulting from 101 IVF pregnancies, which included singletons (n = 62), twins (n = 72), and triplets (n = 9), were compared with equal numbers of non-IVF control subjects. Each pregnancy was matched by maternal age, race, insurance type, neonatal gender, order of gestation, order in delivery, and date of delivery (±6 months). Among the 143 matched gestations, six IVF and seven control infants died, leaving 137 IVF and 136 control neonates for comparison. Results: The IVF mothers had more pregnancy-induced hypertension (21% vs 4%), premature labor (44% vs 22%), labor induction (25% vs 1%), and preterm delivery (37% vs 21%). The IVF infant survivors had a lower mean (±SD) birth weight (2623 ± 857 gm vs 3006 ± 797 gm), more frequent occurrence of low birth weight (42% vs 27%), and shorter gestations (37 ± 4 vs 38 ± 3 weeks). The IVF infants had longer hospitalizations, more days of oxygen therapy, more days of continuous positive airway pressure, and an increased prevalence of respiratory distress syndrome, patent ductus arteriosus, and sepsis. Conclusions: Couples who undergo IVF appear to be at increased risk of having low birth weight and preterm infants, and multiple gestations account for most of the neonatal morbidities. Both the mothers who conceive multiple gestations by means of IVF and their neonates are at an increased risk of having multiple morbidities. (J P EDIATR 1995;127:794-800)

Avoidance of red blood cell transfusion in an extremely preterm infant given recombinant human erythropoietin therapy

To avoid red blood cell (RBC) transfusions, recombinant human erythropoietin (rHuEPO) was given to an infant born at a gestation of 26 weeks and a birthweight of 830 g to parents who were Jehovah's Witnesses. The infant had hyaline membrane disease and required 52 days of assisted ventilation and 19 days of oxygen therapy. He received theophylline therapy for 61 days for recurrent apnoea and bradycardia. He developed bilateral intraventricular haemorrhage (IVH) and left-sided periventricular leucomalacia (PVL). Intravenous rHuEPO was started on day 1 at 200 U/kg per day for 1 month followed by subcutaneous rHuEPO 400 U/kg three times a week for 6 more weeks, supplemented with Vitamin E, folic acid and iron. Blood sampling was kept to a minimum and non-invasive blood-gas monitoring was used consistently. Consequently, the estimated cumulative volume of blood loss from sampling was only 21 mL during his hospital stay. His haemoglobin (Hb) was 150 g/L at birth and this fell to below 100 g/L from day 25 onwards. His lowest leucocyte count was 3.6 x 10(9)/L. He was discharged on day 83 with a Hb of 95 g/L, Hct of 29%, reticulocyte count of 2.8% and weight of 2400 g. At a postnatal age of 3 months, he had a Hb of 113 g/L. At 6 months, investigations showed: Hb 121 g/L, haematocrit 33%, reticulocyte 1% and a weight of 4.4 kg. He was readmitted to hospital once for an episode of vomiting and follow up to date showed developmental delay.(ABSTRACT TRUNCATED AT 250 WORDS)

Perinatal factors associated with retinopathy of prematurity

The etiology of retinopathy of prematurity appears to be multifactorial. Introduction of new treatments in neonatal care may add new risk factors. We have analyzed thc relationship between 42 perinatal factors and the development of retinopathy of prematurity in 78 infants with a birth weight &lt; 1501 g and/or gestational age &lt; 33 weeks. We have also applied a chronological analysis of the maximum and minimum pO2 and pCO2 values. Retinopathy of prematurity was seen in 37 of 78 infants (47.4%). Nineteen factors were found to be related to the development of retinopathy of prematurity. However, when step‐wise logistic regression analysis was used, only birth weight, number of days of oxygen therapy and use of beta‐blocking agents by the mother before birth were found to be associated with the development of retinopathy or prematurity. The results suggest that medication with beta blockers immediately before birth should be used cautiously.

Perinatal factors associated with retinopathy of prematurity.

The etiology of retinopathy of prematurity appears to be multifactorial. Introduction of new treatments in neonatal care may add new risk factors. We have analyzed the relationship between 42 perinatal factors and the development of retinopathy of prematurity in 78 infants with a birth weight < 1501 g and/or gestational age < 33 weeks. We have also applied a chronological analysis of the maximum and minimum pO2 and pCO2 values. Retinopathy of prematurity was seen in 37 of 78 infants (47.4%). Nineteen factors were found to be related to the development of retinopathy of prematurity. However, when step-wise logistic regression analysis was used, only birth weight, number of days of oxygen therapy and use of beta-blocking agents by the mother before birth were found to be associated with the development of retinopathy of prematurity. The results suggest that medication with beta blockers immediately before birth should be used cautiously.

Respiratory failure in infants weighing 1000 g or less at birth.

Yu, V. Y. H., and Hollingsworth, E. (1979). Aust. Paediatr. J., 15, 152–159. Respiratory failure in Infants weighing 1000 g or less at birth. The prognosis for infants weighing &lt;1000 g has improved coincident with the improved ventilatory support in their neonatal management. There are many problems leading to respiratory failure which are particularly significant and peculiar to these infants. Of the 55 infants weighing &lt;1000 g admitted in 1977 and 1978, 58% had hyaline membrane disease and 69% had preterm recurrent apnoea. Fifty‐one infants required assisted ventilation, or whom 28 were ventilated from birth. Though these infants could be ventilated successfully with low peak airway and positive end‐expiratory pressures, 52% of the ventilated infants required it for more than seven days, despite the use of intermittent mandatory ventilation and continuous positive airway pressure during weaning. The neonatal survival rate for assisted ventilation in infants weighing &lt;1000 g was 57%. Seventeen of the ventilated infants developed pulmonary interstitial emphysema, a condition which was associated with an increased incidence of pneumothorax (four infants) and bronchopulmonary dysplasia (ten infants). Infants recovering from bronchopulmonary dysplasia required up to 76 days of assisted ventilation and 84 days of oxygen therapy. No major handicaps were detected on follow‐up except for one infant with retrolental fibroplasia. Optimal management of respiratory failure in infants weighing &lt;1000 g can now result in increased survival with morbidity approaching those of larger preterm infants. As our knowledge, skills, techniques and equipment continue to improve, so will survival and morbidity rates.

Airway Resistance in Infants After Various Treatments for Hyaline Membrane Disease: Special Emphasis on Prolonged High Levels of Inspired Oxygen

Thoracic gas volume, airway resistance (Raw), and dynamic lung compliance (CL) were measured in 48 infants surviving after hyaline membrane disease. Some infants were found to have a small reduction in CL after recovery from the acute phase of the illness but no other abnormalities were detected, irrespective of the type of treatment received. When studied again between the ages of 4 and 10 months, CL had returned to normal, but all infants who had been treated with intermittent positive pressure ventilation (IPPV) during the neonatal period were found to have developed a raised Raw. In contrast, all nonventilated infants, including those who had received up to five days of oxygen therapy in concentrations above 80%, had normal lung function. We conclude that IPPV, and not the increased inspired oxygen concentration, damaged the airways and interfered with their growth.

Systemic deposition of metallic mercury

Case 1. A 4-year-old Negro boy was seen at The Johns Hopkins Hospital with a chief complaint of falling, unconsciousness, and jerking of the extremities of 1 day's duration. Except for 5 days of oxygen therapy during the neonatal period, the past history was unrevealing. Careful inquiry elicited no information which would suggest the entrance of metallic mercury into the body. Physical examination was unremarkable. Laboratory studies, which included lumbar puncture, blood calcium, phosphorus, urea nitrogen, and fasting glucose determinations, were within normal limits. Mercury excretion during a 24-hour period, as determined by the polarographic method, was not significant. X-ray examination of the skull, neck, and trunk (Figs. 1, 2, 3) revealed the presence of many small round shadows of