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Question 1
Incorrect
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Which of the following is NOT a risk factor for neonatal polycythaemia?
Your Answer: Delayed clamping of the umbilical cord
Correct Answer: Jaundice
Explanation:Polycythaemia is a commonly occurring neonatal disorder, which is characterized by a venous haematocrit ≥ 65%. It increases the blood viscosity and causes microcirculatory flow impairment in the end-organs. Causes of polycythaemia are multi-factorial, but the significant risk factors are maternal diabetes, SGA, LGA or post-term birth, infants with chromosomal abnormalities, and delayed clamping of the cord. Jaundice is not a recognized risk factor for polycythaemia.
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This question is part of the following fields:
- Neonatology
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Question 2
Incorrect
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A new-born infant is profoundly hypotonic at birth| he has a good heart rate but is in respiratory distress. Which of the following syndromes is most likely to be the cause?
Your Answer: Prader–Willi
Correct Answer: Werdnig–Hoffman disease (spinomuscular atrophy type 1)
Explanation:The spinal muscular atrophies (SMAs) comprise a group of autosomal recessive disorders characterized by progressive weakness of the lower motor neurons. several types of spinal muscular atrophies have been described based on age when accompanying clinical features appear. The most common types are acute infantile (SMA type I, or Werdnig-Hoffman disease), chronic infantile (SMA type II), chronic juvenile (SMA type III or Kugelberg-Welander disease), and adult-onset (SMA type IV) forms.SMA type I – Acute infantile or Werdnig-Hoffman diseasePatients present before 6 months of age, with 95% of patients having signs and symptoms by 3 months. They have severe, progressive muscle weakness and flaccid or reduced muscle tone (hypotonia). Bulbar dysfunction includes poor suck ability, reduced swallowing, and respiratory failure. Patients have no involvement of the extraocular muscles, and facial weakness is often minimal or absent. They have no evidence of cerebral involvement, and infants appear alert.Reports of impaired fetal movements are observed in 30% of cases, and 60% of infants with SMA type I are floppy babies at birth. Prolonged cyanosis may be noted at delivery. In some instances, the disease can cause fulminant weakness in the first few days of life. Such severe weakness and early bulbar dysfunction are associated with short life expectancy, with a mean survival of 5.9 months. In 95% of cases, infants die from complications of the disease by 18 months.
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This question is part of the following fields:
- Neonatology
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Question 3
Correct
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Which of the following congenital diseases is NOT associated with raised alpha-fetoprotein levels?
Your Answer: Down's syndrome
Explanation:Alpha-fetoprotein has significance primarily as a tumour marker, but maternal levels are frequently measured to detect some of the congenital abnormalities, in which the levels of alpha-fetoprotein are either increased or decreased. The conditions associated with raised alpha-fetoprotein levels are: spina bifida, anencephaly, myelomeningocele, oesophageal atresia, congenital nephrotic syndrome, and turner’s syndrome. Down’s syndrome or trisomy 21 is associated with low levels of maternal alpha-fetoprotein.
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This question is part of the following fields:
- Neonatology
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Question 4
Incorrect
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In women undergoing breast augmentation, what is the percentage reduction with respect to successful breastfeeding?
Your Answer: 30%
Correct Answer: 0.25
Explanation:Breastfeeding may be significantly impaired (up to 25%) by breast augmentation. Equally, breast engorgement, which occurs due to vascular congestion, reduces nipple protrusion and subsequent ability to breastfeed successfully. In the latter, regular feeding or expressing is required.
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This question is part of the following fields:
- Neonatology
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Question 5
Incorrect
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Which of the following is true regarding group B beta-haemolytic Streptococcus?
Your Answer: Meningitis is more common in early disease
Correct Answer: Group B beta-haemolytic Streptococcus (GBS) and Escherichia coli are the most common cause of early sepsis
Explanation:Group B beta-haemolytic Streptococcus (GBS) and Escherichia coli are the most common cause of early sepsis. Group B Streptococcus (GBS), also known as Streptococcus agalactiae, is best known as a cause of postpartum infection and as the most common cause of neonatal sepsis. The GBS organism colonizes the vagina, GI tract, and the upper respiratory tract of healthy humans. GBS infection is almost always associated with underlying abnormalities. In elderly persons aged 70 years or older, GBS infection is strongly linked with congestive heart failure and being bedridden.Penicillin remains the drug of choice for group B streptococcal infection but resistance may occur.
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This question is part of the following fields:
- Neonatology
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Question 6
Incorrect
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What is the imaging modality of choice to assess for the presence of developmental dysplasia of the hip (DDH) in a baby born breech?
Your Answer: X-Ray
Correct Answer: USS
Explanation:Developmental dysplasia of the hip (DDH) is a spectrum of anatomical abnormalities of the hip joint in which the femoral head has an abnormal relationship with the acetabulum.Plain radiographs are of limited value for diagnosis in the new-born child because the femoral head and acetabulum are largely cartilaginous. Ultrasound scanning is the investigation of choice to evaluate DDH in infants younger than six months of age and is useful to diagnose more subtle forms of the disorder when a clinical exam is equivocal. It is also the only imaging modality that enables a three-dimensional real-time image of a neonate’s hip.
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This question is part of the following fields:
- Neonatology
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Question 7
Incorrect
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All of the given options cause persistent neonatal hypoglycaemia EXCEPT?
Your Answer: Hypoxia at birth
Correct Answer: Phenylketonuria
Explanation:Neonatal hypoglycaemia is a serious condition that needs prompt attention and management. The accepted criteria to define neonatal hypoglycaemia is blood sugar levels less than 2.2mmol/L during the first 3 days of life and less than 2.5mmol/L later on. Multiple aetiologies and various risk factors are involved in causing hypoglycaemia in new-borns| the most common and important causes include prematurity, erythroblastosis fetalis, hypoxia at birth, sepsis, inborn errors of metabolism, hypopituitarism, and hyperinsulinism due to maternal diabetes. Inborn errors of metabolism that lead to persistent neonatal hypoglycaemia are maple syrup urine disease, glycogen storage disease, fatty acid enzyme deficiencies, and fructose intolerance. Phenylketonuria does not cause hypoglycaemia.
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This question is part of the following fields:
- Neonatology
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Question 8
Incorrect
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Which of the following neonatal skin conditions is NOT benign?
Your Answer: Erythema toxicum neonatorum
Correct Answer: Midline lumbosacral lipoma
Explanation:A lumbosacral lipoma is a form of congenital spinal lipoma and can be regarded as a cutaneous marker of dysraphism. It is not a skin condition but rather represents a defect in the process of neurulation and leads to a constellation of other abnormalities. The most common other systemic abnormalities associated with midline lumbosacral lipoma include complex anorectal and urological malformations. Other mentioned conditions are benign rashes or birthmarks.
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This question is part of the following fields:
- Neonatology
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Question 9
Incorrect
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Which of the following is true regarding congenital hypothyroidism?
Your Answer: Disorders of thyroid hormone metabolism are more common than structural thyroid gland defects
Correct Answer: It may lead to prolongation of unconjugated hyperbilirubinemia
Explanation:Congenital hypothyroidism (CH) is inadequate thyroid hormone production in new-born infants. It can occur because of an anatomic defect in the gland, an inborn error of thyroid metabolism, or iodine deficiency.CH is the most common neonatal endocrine disorder, and historically, thyroid dysgenesis was thought to account for approximately 80% of cases. However, studies have reported a change in the epidemiology, with a doubling in incidence to around 1 in 1500 live new-borns.Infants with congenital hypothyroidism are usually born at term or after term. Symptoms and signs include the following:Decreased activityLarge anterior fontanellePoor feeding and weight gainSmall stature or poor growthJaundiceDecreased stooling or constipationHypotoniaHoarse cryProlonged neonatal jaundice or unconjugated hyperbilirubinemia
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This question is part of the following fields:
- Neonatology
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Question 10
Incorrect
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All of the following conditions because feeding problems for a neonate except for which one?
Your Answer: Hiatus hernia
Correct Answer: Physiological jaundice
Explanation:Physiological jaundice is the condition in which there is a yellow discolouration of the eyes and the skin of the baby caused by the build up of bilirubin in the blood due to an immature liver. No other symptoms accompany physiological jaundice, thus it will not present with difficulty in feeding. All the other conditions listed can present with feeding problems.
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This question is part of the following fields:
- Neonatology
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Question 11
Correct
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A 7 day old male infant, born at term, presents with umbilical bruising and bleeding. History reveals he wasn’t given vitamin K after birth. Blood exam is normal but with a high prothrombin time and activated partial thromboplastin time. What is the most appropriate treatment?
Your Answer: Intravenous vitamin K plus fresh frozen plasma
Explanation:The clinical picture suggests a vitamin K deficiency haemorrhagic disease of the new-born and requires IV vitamin K and fresh frozen plasma. This usually presents with gastrointestinal bleeding, bleeding from the umbilical stump and bruising after 2–7 days.
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This question is part of the following fields:
- Neonatology
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Question 12
Incorrect
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A neonate is born with a suspected duct dependent cyanotic heart disease. Which of the following should be used in the immediate management of the condition?
Your Answer:
Correct Answer: Prostaglandin E1
Explanation:Severe cyanotic heart diseases such as pulmonary stenosis, transposition of the great vessels, hypoplastic left heart syndrome and truncus arteriosus all run the risk of a poor prognosis for a neonate. To continue the supply of oxygen the ductus arteriosus must be kept patent. This can be done with the immediate administration of Prostaglandin E1 as a temporary measure until a surgical intervention such as an atrial septostomy can be done. The closure of the duct can subsequently be initiated with the administration of indomethacin and oxygen.
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This question is part of the following fields:
- Neonatology
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Question 13
Incorrect
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Which of the following is not included in the management of preterm babies with respiratory distress syndrome?
Your Answer:
Correct Answer: Dexamethasone
Explanation:A preterm with respiratory distress syndrome presents with the condition as a result of immature lungs and inadequate surfactant production. Management of RDS therefore includes surfactant therapy, oxygen administration and mechanical ventilation, as well as measures such maintaining acid base levels and blood haemoglobin in an intensive care unit. Dexamethasone is not shown to be particularly effective when given to a preterm, but can however be used to prevent or decrease RDS severity when given to the mother before delivery.
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This question is part of the following fields:
- Neonatology
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Question 14
Incorrect
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At term, what is the normal amount of amniotic fluid?
Your Answer:
Correct Answer: 600ml
Explanation:In the first trimester of pregnancy, amniotic fluid is produced from maternal plasma where there is a rapid bi-directional diffusion across the foetal skin. At 10 weeks the volume is about 25ml. By 16th weeks of gestation the foetal kidneys make urine that contributes to the increasing volume of amniotic fluid, along with nasal secretions. At 20 weeks, the level is 400ml and increases to 800ml at 28weeks, after which it reduces to 600ml at term.
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This question is part of the following fields:
- Neonatology
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Question 15
Incorrect
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Congenital hypothyroidism is associated with which of the following clinical features?
Your Answer:
Correct Answer: Cardiomegaly
Explanation:Congenital hypothyroidism results from insufficient levels of thyroid hormone in the body since birth, which is either due to dysgenesis of the thyroid gland or dyshormonogenesis. The important features of this disease include coarse facial features (macroglossia, large fontanelles, depressed nasal bridge, hypertelorism, etc.), failure to thrive, cardiomegaly, hypotonia, umbilical hernia, and low core body temperature among many others. Frontal bossing is the usual feature of rickets and acromegaly. Mitral regurgitation is not usually associated with congenital hypothyroidism.
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This question is part of the following fields:
- Neonatology
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Question 16
Incorrect
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Which of the following is associated with neonatal vitamin E deficiency?
Your Answer:
Correct Answer: Thrombocytosis
Explanation:Vitamin E deficiency in premature infants has been described as being associated with low haemoglobin levels in the 2nd month of life, haemolytic anaemia associated with thrombocytosis. Recently, low vitamin E concentrations were suspected as being associated with sudden death in infancy.
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This question is part of the following fields:
- Neonatology
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Question 17
Incorrect
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A systolic murmur is heard in an asymptomatic, pink, term baby with normal pulses and otherwise normal examination. There are no dysmorphic features on the routine first-day neonatal check. What is the MOST appropriate action to be taken immediately?
Your Answer:
Correct Answer: Pre-and post-ductal saturations
Explanation:Certain CHDs may present with a differential cyanosis, in which the preductal part of the body (upper part of the body) is pinkish but the post ductal part of the body (lower part of the body) is cyanotic, or vice versa (reverse differential cyanosis). The prerequisite for this unique situation is the presence of a right-to-left shunt through the PDA and severe coarctation of the aorta or aortic arch interruption or severe pulmonary hypertension. In patients with severe coarctation of the aorta or interruption of the aortic arch with normally related great arteries, the preductal part of the body is supplied by highly oxygenated pulmonary venous blood via the LA and LV, whereas the post ductal part is supplied by deoxygenated systemic venous blood via the RA, RV, main pulmonary artery (MPA) and the PDA. In the new-born with structurally normal heart, a differential cyanosis may be associated with persistent pulmonary hypertension of the new-born. In the cases of TGA with coarctation of the aorta or aortic arch interruption, the upper body is mostly supplied by systemic venous blood via the RA, RV, and ascending aorta, whereas the lower body is supplied by highly oxygenated pulmonary venous blood via the LA, LV, MPA, and then the PDA. For accurate detection of differential cyanosis, oxygen saturation should be measured in both preductal (right finger) and post ductal (feet) parts of the body.
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This question is part of the following fields:
- Neonatology
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Question 18
Incorrect
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Female twins are born. They are noted by the midwife to be identical. They separated in the womb after implantation but before day 8.What type of twin is this?
Your Answer:
Correct Answer: Monochorionic diamniotic
Explanation:A monochorionic diamniotic (MCDA) twin pregnancy is a subtype of monozygotic twin pregnancy. An MCDA pregnancy results from a separation of a single zygote at ,4-8 days (blastocyst) following formation. These fetuses share a single chorionic sac but have two amniotic sacs and two yolk sacs. It accounts for the vast majority (70-75%) of monozygotic twin pregnancies although only ,30% of all twin pregnancies. The estimated incidence is at ,1:400 pregnanciesThe layman term is that the twins are identical – in reality, they are phenotypically similar, and of course of the same gender.
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This question is part of the following fields:
- Neonatology
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Question 19
Incorrect
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Parents of a new-born are worried about cot death. What advice will you give?
Your Answer:
Correct Answer: Child should sleep on the back with legs towards the end of the cot
Explanation:Cot death also know as SIDS or Sudden Infant Death syndrome. Putting a baby to sleep on his back has been shown to reduce the risk of SIDS.
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This question is part of the following fields:
- Neonatology
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Question 20
Incorrect
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In which of the following ethnic backgrounds are Mongolian blue spots most likely to be found?
Your Answer:
Correct Answer: White European
Explanation:Mongolian spots are, hyper-pigmented, non-blanching patches present on the back and gluteal region at birth. They are commonly found in African and Asian ethnic groups, and can also present in infants of Mediterranean and middle eastern descent. Though the spots usually disappear by puberty, some may persist into adulthood.
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This question is part of the following fields:
- Neonatology
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Question 21
Incorrect
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The new-born hearing test is best carried out within the first four or five weeks of life, until what age can it be performed?
Your Answer:
Correct Answer: 12 weeks
Explanation:Ideally, the test is done in the first 4 to 5 weeks, but it can be done at up to 3 months of age.The identification of all new-borns with hearing loss before age 6 months has now become an attainable realistic goal. In the past, parents and paediatricians often did not suspect a hearing loss until the age of 2-3 years, after important speech and language milestones have not been met. By the time these milestones are missed, the hearing-impaired child has already experienced irreversible delays in speech and language development.
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This question is part of the following fields:
- Neonatology
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Question 22
Incorrect
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Which of the following chemical substances is NOT a component of amniotic fluid?
Your Answer:
Correct Answer: Interleukin-1
Explanation:Amniotic fluid is the protective liquid that surrounds the fetus in utero. It prevents the fetus from injury, protects the umbilical cord from compression, and provides necessary nutrients and a medium for growth and movement. Amniotic fluid originates from the maternal plasma initially, but by 16th week of gestation, fetal kidneys start making urine which contributes to further production of the amniotic fluid. Amniotic fluid contains a number of chemical substances including hormones, tumour markers, nutrients, electrolytes, and immunoglobulins. Main substances found in amniotic fluid include carbohydrates, proteins, lipids, lactoferrin, insulin-like growth factor, granulocyte colony-stimulating factor, erythropoietin, etc. Interleukin-1 is not a component of AF.
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This question is part of the following fields:
- Neonatology
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Question 23
Incorrect
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Which of the following can cause an increase in alpha-fetoprotein in the pregnant mother?
Your Answer:
Correct Answer: Posterior urethral valves
Explanation:Alpha-fetoprotein (AFP) is a plasma protein produced by the embryonic yolk sac and the fetal liver. AFP levels in serum, amniotic fluid, and urine functions as a screening test for congenital disabilities, chromosomal abnormalities, as well as some other adult occurring tumours and pathologies.Pregnant maternal serum AFP levels are elevated in:- Neural tube defects (e.g., spina bifida, anencephaly)- Omphalocele- Gastroschisis- posterior urethral valves- nephrosis- GI obstruction- teratomas
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This question is part of the following fields:
- Neonatology
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Question 24
Incorrect
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A term baby with a birth weight of 4.2 kg with meconium aspiration syndrome is intubated and ventilated. Conventional ventilation was unsuccessful and so a trial of high-frequency oscillatory ventilation has commenced. Chest X-ray shows good lung inflation. There is minimal chest “wobble” on the baby. Settings are mean airway pressure 16, delta P 25, rate 10 Hz, FiO2 0.5. Baby’s oxygen saturations are 94%. Blood gas shows pH 7.19, CO2 9.3 kPa, BE –5. What is the first change that should be made to the ventilation?
Your Answer:
Correct Answer: Increase delta P
Explanation:The baby is not clearing CO2 normally despite normal oxygenation so we should increase the delta P. Higher delta P will increase tidal volume and hence CO2 removal.After initial resuscitation and stabilization, the following should be the ventilator settings used:Rate: 30-40/minutePeak inspiratory pressure (PIP) – determined by adequate chest wall movement.An infant weighing less than 1500 grams: 16-28 cm H2O.An infant weighing greater than 1500 grams: 20-30 cm H2O. Positive end expiratory pressure (PEEP): 4 cm of H2O OR 5-6 cm if FiO2 > 0.90.FiO2: 0.4 to 1.0, depending on the clinical situation.Inspiratory time: 0.3-0.5 sec.After 15 to 30 minutes, check arterial blood gases and pH.If the PaO2 or the O2 saturation is below accepted standards, the FiO2 can be raised to a maximum of 1.0. If the PaO2 or O2 saturation is still inadequate, the mean airway pressure can be raised by increasing either the PIP, PEEP, inspiratory time or the rate, leaving inspiratory time constant.If the PaCO2 is elevated, the rate or peak inspiratory pressure can be raised.
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This question is part of the following fields:
- Neonatology
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Question 25
Incorrect
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Which of the following is the treatment of choice for confirmed neonatal cytomegalovirus pneumonia?
Your Answer:
Correct Answer: Ganciclovir
Explanation:One of the most common congenital viral infections is cytomegalovirus infection. It is caused by herpesvirus type 5. The clinical features include failure to thrive, intellectual disability, epilepsy, and microcephaly. The most common clinical complication is sensorineural deafness. The drug of choice for the treatment of neonatal CMV infection is ganciclovir, an anti-viral drug that has shown to prevent deafness.
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This question is part of the following fields:
- Neonatology
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Question 26
Incorrect
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Which of the following is a risk factor for intrauterine growth restriction?
Your Answer:
Correct Answer: Foetal echogenic bowel
Explanation:Intrauterine growth restriction refers to the failure of the fetus to grow in accordance with the weeks of gestation. There are two types of growth restriction, symmetrical and asymmetrical. Causes include various genetic abnormalities, fetal infections, maternal health conditions, etc. Risk factors for the development of IUGR include fetal echogenic bowel, maternal age above 40 years, low PAPP-A levels, maternal smoking or cocaine use, etc. Fetal echogenic bowel implies a brighter than usual fetal intestines on ultrasonography. It is a marker associated with trisomy 21, which is a cause of IUGR.
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This question is part of the following fields:
- Neonatology
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Question 27
Incorrect
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A term baby with a birth weight of 3.6 kg with hypoxic ischaemic encephalopathy is intubated and ventilated. Cooling treatment has started. The baby is sedated and paralysed and is being ventilated on the mode continuous mandatory ventilation (CMV). Settings are: targeted tidal volume 14 ml, maximum PIP 25, PEEP 5, rate 60/min, FiO2 0.21. Baby’s oxygen saturations are 100%. Blood gas shows pH 7.47, CO2 2.8 kPa, BE –6.What is the first change that should be made to the ventilation?
Your Answer:
Correct Answer: Decrease rate
Explanation:Ventilatory rates of 40-60 breaths/min should be provided initially, with proportionally fewer assisted breaths provided if the infant’s spontaneous respiratory efforts increase. Although this practice has not been extensively studied, initial inflation of the new-born’s lungs with either slow-rise or square-wave inflation to a pressure of 30-40 cm H2 O for approximately 5 seconds has been reported to result in more rapid formation of Functional Residual Capacity (FRC).At the moment of delivery and first breath, the neonatal lung is converting from a fetal non-aerated status to a neonatal status. The neonatal lung requires gas exchange, and this necessitates the development of FRC with the resorption of lung fluid and the resolution of most of the atelectasis. Therefore, initial slow ventilation with more prolonged inspiratory times may be useful to assist in this task, balanced against the need to avoid inappropriate inspiratory pressures.Flow-controlled, pressure-limited mechanical devices are acceptable for delivering PPV. These mechanical devices control flow and limit pressure and be more consistent than bags. Self-inflating and flow-inflating bags remain a standard of care. Laryngeal mask airways are effective for assisted ventilation when bag-mask ventilation and intubation are unsuccessful.
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This question is part of the following fields:
- Neonatology
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Question 28
Incorrect
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A nuchal translucency measurement is taken from the nape of the foetus' neck to screen for Down's syndrome.Which of these is the embryological origin of this tissue?
Your Answer:
Correct Answer: Ectoderm
Explanation:The origins of the neural tube and the nape of the neck where nuchal translucency measurements are taken are from embryonic ectoderm.The structural development of the head and neck occurs between the third and eighth weeks of gestation. The 5 pairs of branchial arches, corresponding to the primitive vertebrae gill bars, that form on either side of the pharyngeal foregut on day 22 are the embryologic basis of all the differentiated structures of the head and neck. Each arch consists of 3 layers: an outer covering of ectoderm, an inner covering of endoderm, and a middle core of mesenchyme. These arches are separated further into external, ectoderm-lined pharyngeal clefts and internal, endoderm-lined pharyngeal pouchesA population of ectodermal cells adjacent to the neural fold and not included in the overlying surface (somatic) ectoderm gives rise to the formation of the neural crest. These neuroectodermal crest cells are believed to migrate widely throughout the developing embryo in a relatively cell-free enriched extracellular matrix and differentiate into a wide array of cell and tissue types, influenced by the local environment. Most connective and skeletal tissues of the cranium and face ultimately come from the derivatives of neural crest cells.
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This question is part of the following fields:
- Neonatology
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Question 29
Incorrect
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Which of the following is responsible for the closure of the ductus arteriosus at birth?
Your Answer:
Correct Answer: Reduced level of prostaglandins
Explanation:The ductus arteriosus is normally patent during fetal life| it is an important structure in fetal development as it contributes to the flow of blood to the rest of the fetal organs and structure. From the 6th week of fetal life onwards, the ductus is responsible for most of the right ventricular outflow, and it contributes to 60% of the total cardiac output throughout fetal life. Only about 5-10% of its outflow passes through the lungs.This patency is promoted by continual production of prostaglandin E2 (PGE2) by the ductus.In the foetus, the oxygen tension is relatively low, because the pulmonary system is non-functional. Coupled with high levels of circulating prostaglandins, this acts to keep the ductus open. The high levels of prostaglandins result from the little amount of pulmonary circulation and the high levels of production in the placenta.At birth, the placenta is removed, eliminating a major source of prostaglandin production, and the lungs expand, activating the organ in which most prostaglandins are metabolized. In addition, with the onset of normal respiration, oxygen tension in the blood markedly increases. Pulmonary vascular resistance decreases with this activity.Normally, functional closure of the ductus arteriosus occurs by about 15 hours of life in healthy infants born at term. This occurs by abrupt contraction of the muscular wall of the ductus arteriosus, which is associated with increases in the partial pressure of oxygen (PO2) coincident with the first breath. A preferential shift of blood flow occurs| the blood moves away from the ductus and directly from the right ventricle into the lungs. Until functional closure is complete and PVR is lower than SVR, some residual left-to-right flow occurs from the aorta through the ductus and into the pulmonary arteriesA balance of factors that cause relaxation and contraction determine the vascular tone of the ductus. Major factors causing relaxation are the high prostaglandin levels, hypoxemia, and nitric oxide production in the ductus. Factors resulting in contraction include decreased prostaglandin levels, increased PO2, increased endothelin-1, norepinephrine, acetylcholine, bradykinin, and decreased PGE receptors. Increased prostaglandin sensitivity, in conjunction with pulmonary immaturity leading to hypoxia, contributes to the increased frequency of patent ductus arteriosus (PDA) in premature neonates.Although functional closure usually occurs in the first few hours of life, true anatomic closure, in which the ductus loses the ability to reopen, may take several weeks. The second stage of closure related to the fibrous proliferation of the intima is complete in 2-3 weeks.
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This question is part of the following fields:
- Neonatology
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Question 30
Incorrect
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A neonate was delivered 24 hours ago at the gestational age of 29 weeks. His birth weight was recorded to be 1 kg. Due to his critical state, the baby was intubated and ventilated. Prior to his intubation, the baby was managed with CPAP, but he seemed to get exhausted. He is now on SiMV (spontaneous intermittent mechanical ventilation). The ventilator settings are as follows: targeted tidal volume 9 ml, maximum PIP 30, PEEP 5, rate 40/min, FiO2 0.3. Baby's oxygen saturations are 93%. Blood gas shows pH 7.41, CO2 3.9 kPa, BE -4. Which of the following changes need to be made to the ventilator settings initially?
Your Answer:
Correct Answer: Decrease targeted tidal volume
Explanation:Synchronized IMV (SIMV) with pressure support, used in the alert infant. SIMV guarantees a minimum minute volume while allowing the patient to trigger spontaneousbreaths at a rate and volume determined by the patient. Extra breaths are boosted with pressure support. Tidal Volume (Vt) is normally approximately 6-10 mL/kg and 4-6 ml/kg in the preterm.Respiratory rate (RR) is usually 30-60 BPM. Tidal volume and respiratory rate are relatedto respiratory minute volume as follows: Vm(mL/min) = Vt x RR .This baby is overventilated with a low CO2. Tidal volumes should generally be targeted at 4–6 ml/kg and this baby is being targeted at 9 ml/kg which exposes the baby to damage to the distal airways from this ventilation which can lead to bronchopulmonary dysplasia.
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This question is part of the following fields:
- Neonatology
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