When the respiratory system of a newborn (neonate) is not fully developed or not operating properly at the time of birth, the newborn's chances of survival are greatly reduced. One method of helping to correct this life-threatening situation is to place the newborn on a heart-lung machine called an Extracorporeal Membrane Oxygenation (ECMO). The purpose of ECMO is to recirculate the blood and oxygenate it so that the lungs can rest. However, given the fragile state of a newborn in severe respiratory distress, the use of ECMO itself can be life-threatening. Therefore, ECMO should only be used on those neonates for whom survival is most uncertain.

What are the factors that most influence the probability of survival? Which factors should doctors use as guidelines for placing a neonate on a heart-lung machine?

Eight tests were performed on 30 neonates born with potentially life-threatening respiratory distress. Fourteen survived and sixteen did not. Here are the descriptions of the tests:

• Status (D=deceased, L=living)
• ID Number (within Status)

• pH = hydrogen ion concentration (acidity) of the blood
• pCO2 = concentration (pressure) of carbon dioxide in the blood stream
• pO2 = concentration (pressure) of oxygen in the blood stream
• BE = Base Excess = acid-base balance in the blood
• IMV = Intermittent Mandatory Ventilation = higher means lower dependence on a mechanical ventilator
• PL = Pressure Limit = maximum pressure by a ventilator permitted for the infant's lungs
• PEEP = Positive End Expiratory Pressure
• AaDO2 = Difference in oxygen levels between arteries and aveoli

Tasks:

• Perform a regression/correlation analysis on the data (with the above goals in mind)
• Principle Component Analysis (PCA)
• ANOVA

Here are the data:

Status ID   pH  pCO2 pO2 BE  IMV  PL PEEP AaDO2
  D     1  7.51  28   36  2   96  55   3   650
  D     2  7.55  22   48  0   40  40   5   655
  D     3  7.49  18  139 -5   65  33   3   569
  D     4  7.47  29   66  0   68  41   7   620
  D     5  7.37  32   47 -5   60  40   3   646
  D     6  7.59  25  182  6   70  32   5   491
  D     7  7.55  32   47 -7   75  45   5   634
  D     8  7.40  21   75  4  120  45   7   614
  D     9  7.54  20   88 -2   90  35   5   614
  D    10  7.58  25   58  4   85  29   2   641
  D    11  7.61  20   66  2   50  30   5   634
  D    12  7.53  22   41 -1   45  45   5   651
  D    13  7.53  21   33 -1   66  30   6   633
  D    14  7.62  21   68  4   40  28   3   638
  D    15  7.69  13   39  1   80  44   6   656
  D    16  7.41  35   53  0  100  46   3   633
  L     1  7.52  25  178  0   65  32   3   452
  L     2  7.53  25   48  2   47  30   5   645
  L     3  7.51  21   56 -2   80  35   5   637
  L     4  7.46  25   65 -3   55  30   5   618
  L     5  7.69  14   40  2   80  32   4   657
  L     6  7.55  16  151 -4   67  30   5   528
  L     7  7.58  15  281 -7   46  26   6   385
  L     8  7.38  26  130 -7   55  33   6   551
  L     9  7.64  18  222  3   60  24   4   436
  L    10  7.48  25   70 -2   60  32   5   621
  L    11  7.52  20  107 -2  100  48   6   594
  L    12  7.42  38   59  1   55  23   4   571
  L    13  7.52  26   38 -3   40  47   5   656
  L    14  7.72  22   43 12   87  45   4   648