Why pregnant women should avoid use of insecticides, insect repellants
What You Should Know About RSV In Babies
RSV is a respiratory infection that is common and sometimes serious in babies. Some symptoms include difficulty breathing, lethargy, cough, and more.
Respiratory syncytial virus (RSV) is a serious respiratory infection that can affect people of all ages.
But RSV is most serious when it occurs in babies. That's because babies' airways aren't as well-developed, so they cannot cough up mucus like older children or adults. Also, their airways are smaller, so they can experience airway blockage easily, causing trouble breathing.
In many people, RSV causes cold symptoms, often with a cough. In babies, RSV can cause a more serious illness called bronchiolitis. Babies with bronchiolitis have wheezing along with their cough.
RSV can lead to other severe infections, including pneumonia. In some cases, babies may need to receive treatment at a hospital.
RSV is a virus, so there are currently no medications that can cure it to shorten the course of the illness. Instead, doctors will often recommend treatments or remedies to help manage symptoms until the infection passes.
People often transmit RSV from November to April, when cooler temperatures bring people indoors and when they're more likely to interact with others. People can also transmit RSV earlier in the year. For example, in 2022, the RSV season started earlier, with a high number of cases in October. Transmission can also occasionally happen during summer months.
In older children, RSV can cause symptoms similar to that of a cold. But in babies, the virus causes more severe symptoms.
RSV tends to follow a timeline of symptoms. Symptoms often appear 4 to 6 days after exposure to the virus. However, a baby may start experiencing symptoms earlier or later.
Symptoms a baby may have with RSV include:
Some babies are more likely to experience RSV symptoms. Research from 2022 indicates this to especially be true for those born prematurely or babies with heart problems or a history of wheezing or breathing issues.
RSV vs. COVID-19RSV and COVID-19 are both respiratory infections and share many similar symptoms. Both conditions can cause fever, cough, runny nose, and sneezing. Upset stomach, vomiting, or diarrhea may also occur in babies with COVID-19.
If your child has any of the above symptoms, their pediatrician may recommend testing them for both RSV and COVID-19, depending on cases in your area and their exposure risk to either of these viruses.
RSV cases can range from mild cold symptoms to those of severe bronchiolitis. Even if symptoms are mild, it's important to call your pediatrician if you suspect your baby has RSV. Always get emergency medical care if your baby appears to have trouble breathing.
Emergency symptoms to watch out for include:
In the most severe cases, RSV may require the help of a breathing machine known as a mechanical ventilator. This machine can help to inflate your baby's lungs until the virus goes away.
Doctors used to routinely treat many cases of RSV with bronchodilators. Some doctors still use bronchodilators for RSV treatment, but experts no longer recommend this for the most part.
Doctors prescribe bronchodilators for people with asthma or COPD to help open up the airways and treat wheezing, but they don't help the wheezing that comes with RSV bronchiolitis.
If your baby has dehydration, their doctor may also provide intravenous fluid.
Antibiotics won't help your baby's RSV because antibiotics treat bacterial infections. RSV is a viral infection.
If your doctor gives you the OK to treat RSV at home, you'll likely need a few tools. These will keep your baby's secretions (mucus) as thin as possible so they don't affect their breathing.
A bulb syringeYou can use a bulb syringe to clear thick secretions from your baby's nose.
To use the bulb syringe:
It's especially important to use the bulb syringe before your baby's feeding. A clear nose makes it easier for your baby to eat. Combine the tool use with over-the-counter saline drops, which you can place into each nostril and suction out afterward.
Cool mist humidifierA humidifier can introduce moisture into the air, helping thin your baby's secretions. Make sure to clean and care for the humidifier properly.
Hot water or steam humidifiers could be harmful to your baby because they can cause scalding.
You can talk with your child's doctor about treating any fevers with acetaminophen. Your doctor will suggest a dose based on your baby's weight. Do not give your baby aspirin, as this can harm their health.
Providing fluids, such as breast milk or formula, can prevent dehydration in your baby. You can also ask your doctor about potentially giving your baby an electrolyte-replacing solution, like Pedialyte.
Keep your baby in an upright position, which makes it easier for them to breathe. You can keep your baby more upright in a stable and secure car seat or baby seat while they are awake during the day.
Except while in a car, never put a baby to sleep in a car seat due to the risk of suffocation. If using a car seat to prop your baby up while they are awake, place the car seat on a stable, secure, low surface with direct supervision at all times.
Limiting your baby's exposure to cigarette smoke is also vital to keeping them healthy. Cigarette smoke can make your baby's symptoms worse.
When an otherwise healthy baby has RSV, they can pass on the infection to someone for 3 to 8 days. Try to keep the child with the infection separate from other siblings or children to prevent transmission.
RSV is transmissible through direct and indirect contact with a person who has an active infection. Transmission can involve touching a person's hand after they sneeze or cough, then rubbing your eyes or nose.
Frequent handwashing with warm, soapy water for at least 20 seconds per time is the best way to reduce the risk of RSV. It's also important to help your baby cover sneezes and coughs.
The virus can also live on hard surfaces, such as a crib or toys, for several hours. If your baby has RSV, regularly clean toys and surfaces where they play and eat to help reduce the spread of germs.
Babies can make a full recovery from RSV in 1 to 2 weeks. Most babies can recover from RSV without receiving treatment in a hospital setting.
If you think your baby has dehydration or is in moderate to severe distress, get emergency medical care.
Early Isomerization Of Bilirubin In Phototherapy Of Neonatal Jaundice
This study has shown that 4Z, 15E bilirubin, which begins to form as soon as an infant is exposed to phototherapy lights, is detectable in blood within 15 min. By this time, a mean of ∼10% of circulating bilirubin had undergone isomerization to 4Z, 15E bilirubin. Small amounts of other photoisomers were also detectable by HPLC but were not quantitated for this study.
In three patients, the proportion of 4Z, 15E bilirubin reached 14–15% of the total bilirubin after only 15 min of phototherapy. Interestingly, in two of them, irradiance values >40 W/m2 were measured on the body surface closest to the lights, whereas values >30 W/m2 were measured in their flanks. In the third patient, corresponding irradiance values were 30.2 and 18.6 W/m2, respectively. All three had high TSB values when phototherapy was started (315, 254, and 315 μM, respectively), and all three were relatively low birthweight, weighing 2670, 1760, and 1680 g, respectively.
Despite precautions to minimize exposure of samples to light, small amounts of 4Z, 15E bilirubin were present in blood even before phototherapy, although in much smaller amounts than in previous studies (6,7). Whether these isomers hail from the patient, or were the result of accidental ambient light exposure of blood samples during collection and preparation, cannot be answered from our study. The 4Z, 15E bilirubin has been demonstrated in nonjaundiced subjects exposed to daylight (8). Therefore, it may not be unreasonable to speculate that some photoisomer production will occur in jaundiced infants exposed to bright nursery lights. In recent years, pursuant to the introduction of NIDCAP (10) or similar care principles in many NICUs, ambient nursery lights are likely to be much more subdued than when earlier phototherapy studies were performed (11).
The 2004 American Academy of Pediatrics (AAP) guidelines on management of neonatal jaundice (12) arbitrarily defined intensive phototherapy as an irradiance >30 μW/cm2/nm over the wavelength interval 430–490 nm. The mean irradiance value measured on the infants' uppermost surface (i.E. Closest to the lights) in this study was 26.7 ± 7.8 W/m2 (wavelength interval 380–780 nm). In sample measurements with an older Air-Shields PR III Phototherapy Radiometer that yields values in μW/cm2/nm (wavelength interval 330–570 nm), the mean irradiance values in our study seem to be close to the range defined by the AAP as "intensive" despite the low wattage (9 W) and small size (≈13 cm) of the bulbs used in our units. However, as irradiance measurements may vary between devices depending on the calibration and type of irradiance meter, a meaningful correlation between our W/m2 measurements and the AAP definition is not possible.
In some previous studies, "360°" phototherapy was used, achieved either through specially constructed tube-shaped phototherapy units with cribs that had a translucent bottom or with the infant lying on a fiberoptic mat while receiving fluorescent phototherapy from above and sides (13–15). Initial rates of photoisomer formation with these units are not well defined. Interestingly, using what were described as "special blue" bulbs (TL20/52), Myara et al. (7) observed conversion of >30% of the total bilirubin in the serum to Z/E photoisomers in neonates after 3 h of phototherapy, whereas, using 40-W "violet-blue" (Philips TL40/03) fluorescent tubes, Agati et al. (16) observed ∼25% of conversion within 6 h in an adolescent Crigler-Najjar type I patient. However, in both of those studies, the proportion of bilirubin photoisomers at time 0 was high (12–18%). The rate of photoisomerization is a function of the wavelength output of the lights, the intensity of the lights, the surface area of the baby exposed, and possibly the initial serum bilirubin level, whereas the percentage conversion of bilirubin to 4Z, 15E bilirubin is expected to increase with time to a photostationary value that is dependent only on the wavelengths emitted by the light.
The strength of this study is that the group of patients studied is representative of typical NICU populations regarding the distribution of birth weights and gestational ages. Because of the characteristics of Norwegian guidelines for therapy (which are similar to the AAP guidelines), some infants were treated at relatively low TSB levels. The phototherapy units we have used are commercially available and widely used. The use of white linen inside the crib and hung around the phototherapy unit to increase irradiance by reflection can be replicated anywhere using materials easily available and may increase the efficacy of phototherapy (17,18). Thus, the rates of bilirubin stereoisomer formation that we have found in this study are likely to be achievable in other NICUs as well.
It is noteworthy that after 2 h of phototherapy, the reduction of TSB levels from time 0 was not significant. This may seem somewhat surprising, given the substantial reductions in TSB levels that have previously been documented within the same time interval (19). However, in that study, the TSB levels were extreme, which predicts a more dramatic response to phototherapy. Significantly, ∼20% of TSB at 2 h was in the form of the 4Z, 15E photoisomer. If, as appears possible considering their physicochemical characteristics, photoisomers of bilirubin have less ability to cross the blood-brain barrier than the predominant IXα (Z,Z) isomer, this may translate into a lesser threat to the brain.
Kernicterus regrettably continues to occur, although with due precautions it ought to be avoidable. Reports of infants admitted with extreme jaundice and neurologic symptoms compatible with intermediate to advanced stage acute bilirubin encephalopathy keep surfacing among neonatologists. Recent publications suggest that intermediate to advanced stage acute bilirubin encephalopathy can occasionally be reversible in neonates (4,20,21), as also observed in adult patients with Crigler-Najjar syndrome (22). Expedient and aggressive treatment seems to be a common theme in these reports.
None of the patients in this study had any signs of bilirubin-induced neurologic dysfunction. Therefore, reversibility of neurotoxicity during the study period could not be assessed. Analysis of bilirubin in CSF might have answered the question of whether bilirubin efflux from the CNS is dependent on the relative concentrations of (Z,E) vs (Z,Z) bilirubin IXα in serum. However, extant Norwegian ethics rules would not have permitted repeated lumbar punctures for this purpose or is it likely that consent could have been obtained.
Herein, we have confirmed that formation of significant amounts of 4Z, 15E bilirubin occurs in phototherapy long before any alternative or adjunctive treatment could have been instituted. The clinical implications of converting such a large proportion of a major metabolite in the circulation to a different form, with a different three-dimensional structure, markedly different lipophilicity, and different serum albumin binding properties, are unknown. With respect to bilirubin toxicity, there are, a priori, three possibilities: the photoisomer has similar toxicity to the "natural" isomer; the photoisomer is more toxic; or the photoisomer is less toxic. Of these, the first is unlikely because of the different structures and physicochemical properties of the two forms and the need for pigment to enter the brain to cause toxicity. The second possibility also seems unlikely because countless phototherapy treatments over the last half-century seem never to have caused or exacerbated CNS toxicity. This leaves the third possibility; the most likely in view of the much lower lipophilicity of the photoisomer compared with the 4Z, 15Z isomer, which would be expected to make it less prone to cross the blood-brain barrier and enter the brain. However, the magnitude of such an effect could be insignificantly small, and it remains unknown whether photoisomerization engenders a rapid detoxification process, as proposed long ago (23), or has little effect on the potential toxicity of all forms of bilirubin in the circulation.
327 Excessively High Bilirubin And Exchange Transfusion In Very Low Birth Weight Infants
Objective: To evaluate the distribution of peak serum bilirubin levels in very low birth weight (VLBW) infants and the performance of exchange transfusion in infants with excessively high bilirubin levels.
Methods: A population based observational study using data collected by the Israel National VLBW Infant Database. The study sample comprised 13,499 infants of 24 to 33 weeks gestation. Two definitions of excessively high peak bilirubin levels which might be considered as threshold levels for performance of exchange transfusion were used. Firstly, a bilirubin level of ≥ 15 mg/dL for all infants (PSB-15), and secondly, incremental bilirubin levels ranging from 12-17 mg/dL according to gestational age (PSB-GA). Multivariable logistic regression analyses were performed to examine the factors associated with performance of exchange transfusion.
Results: Four hundreds sixty eight (3.5%) and 1035 infants (7.7%) infants in the PSB-15 and in the PSB-GA groups respectively had peak serum bilirubin levels above thresholds for exchange transfusion. Exchange transfusion's were performed in only 66 (14.1%) of these infants in the PSB-15 group and 91 (8.8%) in the PSB-GA group. In both groups performance of exchange transfusion was significantly associated with peak serum bilirubin levels, with an odds ratio of 1.38 for each mg/dL increase above the threshold level.
Conclusion: Exchange transfusion was performed in only 9-14% of VLBW infants with excessively high bilirubin levels. This may be related to an absence of definitive guidelines or the possible belief that the risks of exchange transfusion outweigh the potential risk of bilirubin induced neurological injuries.
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