title: Effects of transient intrathoracic pressure changes (hiccups) on systemic arterial pressure.
abstract: The purpose of the study was to determine the effect of transient changes in intrathoracic pressure on systemic arterial pressure by utilizing hiccups as a tool. Values of systolic and diastolic pressures before, during, and after hiccups were determined in 10 intubated preterm infants. Early-systolic hiccups decreased systolic blood pressure significantly (P < 0.05) compared with control (39.38 +/- 2.72 vs. 46.46 +/- 3.41 mmHg) and posthiccups values, whereas no significant change in systolic blood pressure occurred during late-systolic hiccups. Diastolic pressure immediately after the hiccups remained unchanged during both early- and late-systolic hiccups. In contrast, diastolic pressure decreased significantly (P < 0.05) when hiccups occurred during diastole (both early and late). Systolic pressures of the succeeding cardiac cycle remained unchanged after early-diastolic hiccups, whereas they decreased after late-diastolic hiccups. These results indicate that transient decreases in intrathoracic pressure reduce systemic arterial pressure primarily through an increase in the volume of the thoracic aorta. A reduction in stroke volume appears to contribute to the reduction in systolic pressure.
authors.affiliation: Department of Pediatrics, East Carolina University School of Medicine, Greenville, North Carolina 27858, USA.
authors.forename: O P
authors.initials: OP
authors.lastname: Mathew
mesh_terms: D001794:Blood Pressure / Q000502:physiology*; D003971:Diastole; D006606:Hiccup / Q000503:physiopathology*; D006801:Humans; D007231:Infant, Newborn; D011312:Pressure; D013599:Systole; D013909:Thorax / Q000503:physiopathology*