Table 1.
Definition of variables.
| Definitions | Authors | ||||||
|---|---|---|---|---|---|---|---|
| 1995; Menticoglou [18] |
2007; Cheng [19] | 2009; Allen [4] | 2009; Rouse [20] | 2012; Bleich [21] | 2017; Sandström [22] | 2019; Infante [23] | |
| Acidosis | NR | NR | NR | NR | NR | A pH value <7.05 and base excess <−12 in the umbilical artery. | NR |
| Birth depression | NR | NR | Delay in initiating and maintaining respirations after birth requiring resuscitation by mask or endotracheal tube for at least 3 min, a 5 min Apgar score of 3 or less, or neonatal seizures due to hypoxic-ischemic encephalopathy. | NR | NR | NR | NR |
| Intubation | NR | NR | NR | Intubation in delivery room. | NR | NR | NR |
| Heart compressions | NR | NR | NR | NR | NR | Resuscitation in delivery room with heart compressions and/or intubation. | NR |
| Advanced neonatal resuscitation | NR | NR | NR | NR | NR | NR | Type III: Oxygen therapy with positive intermittent pressure. Type IV: Endotracheal intubation, Type V: Cardiac massage and/or using drugs |
| Admission to Neonatal Intensive Care Unit | Need for admission to the Neonatal Intensive Care Unit for any reason at all or with a 5 min Apgar score < 7 or arterial cord pH < 7.20. | NR | Neonatal intensive care unit admission with duration of stay longer than 24 h. | Admission to a neonatal intensive care unit for >48 h. | NR | NR | NR |
| Prolonged neonatal stay | NR | Neonatal stay >2 d for vaginal delivery and >4 d for caesarean delivery. | NR | NR | NR | NR | NR |
| Neonatal seizures | NR | NR | NR | NR | Seizures in the first 24 h of life. | NR | NR |
| Sepsis | NR | NR | Positive blood culture, septicemia or systematic infection. | NR | Positive blood culture. | NR | NR |
| Minor trauma | NR | NR | One or more of the following neonatal traumas: linear skull fracture, other fractures (clavicle, ribs, numerus, or femur), facial palsy, or cephalohematoma. | NR | NR | NR | NR |
| Major trauma | NR | NR | One or more of the following neonatal traumas: depressed skull fracture, intracranial hemorrhage, or brachial plexus palsy. | NR | NR | NR | NR |
| Composite neonatal morbidity | NR | Composite variable for 5 min Apgar <7, UA pH <7.0, UA base excess ≥12, shoulder dystocia, NICU stay, and birth trauma (which includes brachial plexus injury, facial nerve palsy, clavicular fracture, skull fracture, head laceration, and cephalohematoma defined and diagnosed by the attending pediatrician). | Composite of any of the other neonatal outcomes. | Any of the following occurrences: a 5 min Apgar score <4, an umbilical artery pH <7.0, seizures, intubation, stillbirth, neonatal death, or admission to a NICU. | NR | NR | Composite of any of the other neonatal outcomes. |
| Neonatal death | Death during the second stage of labor or in the first 28 d of life | NR | NR | NR | NR | NR | NR |
NR: not reported.