Table 2.

Cardiac function, hemodynamics, and serum cortisol in study infants (n=45)

	Part A		Part B
	Normotension	Hypotension	Hypotension
	No Hypotension (n=27)	Hypotension (all types) (n=18)	Volume- boluses alone (n=8)	Catecholamine- responsive (n=6)	Catecholamine- resistant (n=4)
LVO (ml/kg/min)	240±58	216±79§	201±40	224±132	235±38
LVO <150 ml/kg/min (%)	8	17	13	33	0
Shortening Fraction ≤25% (%)	15	50*	63	33	50
MPI	0.42±0.12	0.47±0.21	0.47±0.12	0.41±0.23	0.58±0.30
MPI >2z (%)	11	33§	25	33	50
LVEDD (cm/kg)	1.32±0.37	1.36±0.31	1.42±0.28	1.29±0.41	1.33±0.25
LA/Ao	1.51±0.34	1.44±0.53	1.54±0.49	1.32±0.33	1.39±1.02
SVR (mm Hg/L/kg/min)	167±74	187±99	202±78	216±132	110±44**
Heart Rate (beats/min)	155±13	162±19	153±14	160±24	180±5**
Stroke Volume (ml/kg)	1.56±0.42	1.34±0.46	1.33±0.33	1.36±0.72	1.31±0.24
VCFc (Circ/sec)	1.24±0.30	1.25±0.36	1.18±0.39	1.33±0.22	1.25±0.51
Wall Stress (g/cm2)	31±19	29±19	41±23	20±5	17±7§§
Cortisol (ng/ml) median (interquartile range)	24 (10–54)	42 (10–84)	60 (22–100)	51 (33–367)	8 (2–12)**

Definitions: Hypotension (all types), all hypotension groups combined (i.e., infants who received volume-resuscitation/boluses alone, catecholamine-responsive infants, and catecholamine-resistant infants).

LVO, left ventricular output; MPI, left ventricular myocardial performance index; MPI >2z, MPI greater than 2 standard deviations above the normative mean; LVEDD, left ventricular end-diastolic diameter; LA/Ao, ratio of left atrium to aortic root dimension; SVR, systemic vascular resistance; VCFc, velocity of circumferential fiber shortening (corrected for heart rate);

Values represent mean ± standard deviation or percent (%);

^*p-value <0.05,

^§<0.15: For comparisons between infants with No Hypotension and infants with Hypotension (all types)

^**p-value <0.05,

^§§<0.15: For comparisons between infants with Catecholamine-resistant hypotension and infants with milder types of Hypotension (Volume-resuscitation/boluses-alone and Catecholamine-responsive infants)