Please select the eligibility criteria that correspond to the clinical trial below.
Title: A Randomized Controlled Trial on the Effectiveness of Inhaled Nitrous Oxide for Pain Relief During ROP Screening Exam in the Pre-term Infant
Brief Summary: The primary objective of the proposed study is to show that inhaled equimolar mixture of oxygen and nitrous oxide (EMONO) will reduce pain associated with retinal exam in the preterm infant, as compared to the current standard treatment (oral sucrose and topical anaesthesia).

The investigators also aim to show that EMONO can be used safely in preterm neonates undergoing retinal exam, and will not result in any increase in apnea, bradycardia, or desaturation in the 24 hours following the exam. Finally, the investigators aim to show that EMONO will keep the infant calm, and make retinal examination easier and less traumatic.


Options:
A: Inclusion Criteria:

1. All Infants with gestational age between 30 1/7 and 36 6/7 weeks
2. Within 30 days of post-natal life
3. Breast milk is available for the neonate
4. Scheduled for a blood draw

Exclusion Criteria:

1. Neonates on intravenous or peroral medications for sedation/analgesia or anti-epileptics
2. Infants diagnosed with neonatal abstinence syndrome and neonatal encephalopathy
3. Infants who are critically ill, on assisted ventilation \> 2L HFNC and on ionotropic support
4. Infants with major congenital abnormalities/dysmorphism
B: Inclusion Criteria:

* Informed consent from parent or legal guardian.
* Term, newborn infant, between 1 and 7 days of age.
* Appropriate for gestational age (weight 5th through 95th percentile).

Exclusion Criteria:

* Small or large for gestational age (weight\<5th or \>95th percentile).
* Physical or biochemical abnormalities.
* History of maternal drug dependence.
* Apgar score \<7 at 5 minutes.
* Current use of analgesics.
C: Inclusion Criteria:

* Healthy, full term, normally breastfeeding infants, whose mother is willing to breastfeed during the painful procedure and consents to study participation. Normally breastfeeding infants will be defined as those infants who had fed directly at the breast a minimum of two times in the 24-hours prior to blood collection and whose mother and/or staff nurse reported active sucking and swallowing during those feeds. Infants who have undergone repeated heel lancing for blood glucose and/or bilirubin monitoring (e.g., small or large for gestational age infants, infants born to diabetic mothers, or with hyperbilirubinemia) will be considered eligible, however, diagnosis and the number of prior painful procedures will be recorded and retained for statistical analysis.

Exclusion Criteria:

* Infants will not be eligible for study participation if they are a twin birth (including all classifications of monozygotic and dizygotic twins) due to the potential for non-independence of outcomes between twin pairs, show signs of infection, significant lower limb tissue damage, have had previous surgery or intra-ventricular hemorrhage, are born to opioid using mothers or with significant genetic disorders, are unable to breastfeed or have contraindications to sucrose administration, or whose parents are unable to provide written informed consent.
D: Inclusion Criteria:

* Requiring retinal exam for ROP screening
* Clinically stable
* At least 30 0/7 weeks of corrected gestational age at the time of study
* Not on mechanical ventilation or CPAP at the time of study
* Requiring an inspired concentration of oxygen less than 50%

Exclusion Criteria:

* - Craniofacial malformations
* Cyanotic cardiac disease
* Hemodynamically significant cardiac lesions
* Known pneumothorax or pneumomediastinum
* Congenital pulmonary malformations
* Neuromuscular disease
* Receiving opiates, benzodiazepines or barbiturates at the time of study

Answer: D