Please select the eligibility criteria that correspond to the clinical trial below.
Title: High Flow Nasal Cannula Versus Nasal Intermittent Mandatory Ventilation for Respiratory Distress Syndrome: a Randomized, Controlled, Prospective Study
Brief Summary: The investigators hypothesize that while the extremely low birthweight (ELBW) infants (\<1000 g) may need NIMV for the treatment of RDS, larger infants or the smaller ones post extubation may enjoy the comfort benefits associated with HFNC while getting coparable respiratory support to NIMV.


Options:
A: Inclusion Criteria:

1. Gestational age between 24 to 34 and 6/7 weeks assessed by the obstetrical team from dating of last menstural period or ultrasound and weight \>1000 g for the initial treatment of RDS or \<35 weeks post extubation or for apnea of prematurity
2. Infants with RDS who will need NRS as initial therapy or after extubation and for apnea of prematurity, 3. written informed consent.

Exclusion Criteria:

1. Significant morbidity apart from RDS including: cardiac disease (not including patent ductus arteriosus \[PDA\]), congenital malformation, or if they had cardiovascular or respiratory instability because of sepsis, anemia or severe intraventricular hemorrhage (IVH),
2. Parents refuse consent.
3. Unavailability of suitable ventilator.
B: Inclusion Criteria:

* Infants born greater than or equal to 28 weeks (28+0) and less than 37 weeks (36+6) gestation
* CPAP pressure of 5 cm H2O
* FiO2 requirement = or \<0.30
* Clinically stable on these CPAP parameters for 24 hours pre-randomization:

  * Respiratory rate less than 60
  * No significant chest recession
  * No apnea requiring bagging and/or
  * Not more than 6 apneas requiring stimulation in the preceding 24 h.
  * Average saturation \> or = 87%
  * Satisfactory ABG (pH\> 7.25, PCO2 \< 60, and Base deficit \< -8)

Exclusion Criteria:

* Life threatening congenital anomalies
* Congenital cyanotic heart diseases
* Congenital airway or chest wall abnormalities
* Pulmonary hypoplasia
* Known or suspected to have a neuromuscular disorder
* Congenital neurological disorder, severe IVH (grade 3 or 4), PVL and hydrocephalus
C: Inclusion Criteria:

* Preterm infants admitted to the NICU at University Hospital of North Norway, Tromsoe, Norway (single center study)

  * Gestational age (GA) \< 34 weeks
  * Corrected age \< 34 weeks
  * Receiving nasal CPAP for respiratory distress
  * Respiratory "stable": FiO2 \< 30%, pCO2 \< 8,5 kPa and pH \> 7.25.
* GA \< 29 weeks: Respiratory "stable" over last 72 h.
* GA 29-33 weeks: Respiratory "stable" over last 24 h.

Exclusion Criteria:

1. Congenital anomalies
2. Ongoing treatment for hypoglycemia or infection
3. Other intercurrent disease requiring frequent blood sampling
D: Inclusion Criteria:

1. Birth weight \> 1000 grams and \> 27 weeks gestation
2. Candidate for non-invasive respiratory support as a result of:

   1. an intention to manage the infant with non-invasive (no endotracheal tube) respiratory support from birth initiated in the first 24 hours of life
   2. an intention to extubate an infant being managed with intubated respiratory support to non-invasive support

Exclusion Criteria:

1. Birth weight \< 1000 grams
2. Estimated gestation \< 29 weeks
3. Participation in a concurrent study that prohibits the use of HHFNC
4. Active air leak syndrome
5. Infants with abnormalities of the upper and lower airways; such as Pierre- Robin, Treacher-Collins, Goldenhar, choanal atresia or stenosis, cleft lip and/or palate, or
6. Infants with significant abdominal or respiratory malformations including tracheo-esophageal fistula, intestinal atresia, omphalocele, gastroschisis, and congenital diaphragmatic hernia.

Answer: A