Increased incidence of sighs (augmented inspiratory efforts) during synchronized intermittent mandatory ventilation (SIMV) in preterm neonates

Helmut Hummler, Tilo Gerhardt, Alvaro Gonzalez, Nelson R Claure, Ruth Everett-Thomas, Eduardo Bancalari

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

A reflex resulting in a deep, sigh-like inspiratory effort (augmented breath) is frequently triggered during synchronized mechanical ventilation in preterm infants. We studied the incidence of augmented inspiratory efforts and their effect on ventilation and lung compliance during conventional IMV and synchronized IMV (SIMV) in 15 preterm neonates (GA 26.7 ± 1.5 wks (mean ± SD), BW 925 ± 222 g, age 1-8 days). Augmentation of spontaneous inspiratory effort was defined as an esophageal pressure deflection occurring coincident with a synchronized mechanical breath and exceeding the previous unassisted spontaneous effort by more than 50%. The incidence of augmented breaths was higher during SIMV (11.1 ± 7.7%; P < 0.01) than during conventional IMV (5.1 ± 6.1%). However, when the synchronized breaths were triggered late (200-300 msec) after the onset of inspiration, augmented breaths occurred no more frequently than during conventional IMV (6.0 ± 4.7%). The incidence of augmented breaths correlated inversely with dynamic lung compliance (P = 0.014), but was not significantly influenced by a change in PEEP. Although inspiratory effort increased nearly three times during the augmented breaths, tidal volume increased only 12%. The change in tidal volume was limited because the augmented effort reached its maximal negativity only approximately 500 ms after the beginning of the synchronized, mechanical breath and at a time when the mechanical breath had already ended. For this reason the augmented effort did not contribute significantly to minute ventilation, but only prolonged inspiration. Dynamic lung compliance did not change significantly after an augmented breath. The results indicate that augmented inspiratory efforts are more common in preterm neonates ventilated with SIMV than with conventional IMV, but do not contribute significantly to ventilation.

Original languageEnglish
Pages (from-to)195-203
Number of pages9
JournalPediatric Pulmonology
Volume24
Issue number3
DOIs
StatePublished - Sep 1 1997

Fingerprint

Ventilation
Lung Compliance
Newborn Infant
Incidence
Tidal Volume
Artificial Respiration
Premature Infants
Reflex
Pressure

Keywords

  • Augmented inspiration
  • Head's paradoxical reflex
  • Mechanical respiration
  • Newborn infant
  • Pulmonary function
  • Synchronized ventilation

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health
  • Pulmonary and Respiratory Medicine

Cite this

Increased incidence of sighs (augmented inspiratory efforts) during synchronized intermittent mandatory ventilation (SIMV) in preterm neonates. / Hummler, Helmut; Gerhardt, Tilo; Gonzalez, Alvaro; Claure, Nelson R; Everett-Thomas, Ruth; Bancalari, Eduardo.

In: Pediatric Pulmonology, Vol. 24, No. 3, 01.09.1997, p. 195-203.

Research output: Contribution to journalArticle

@article{f018cd6dbc5244528f06d23c346ba97c,
title = "Increased incidence of sighs (augmented inspiratory efforts) during synchronized intermittent mandatory ventilation (SIMV) in preterm neonates",
abstract = "A reflex resulting in a deep, sigh-like inspiratory effort (augmented breath) is frequently triggered during synchronized mechanical ventilation in preterm infants. We studied the incidence of augmented inspiratory efforts and their effect on ventilation and lung compliance during conventional IMV and synchronized IMV (SIMV) in 15 preterm neonates (GA 26.7 ± 1.5 wks (mean ± SD), BW 925 ± 222 g, age 1-8 days). Augmentation of spontaneous inspiratory effort was defined as an esophageal pressure deflection occurring coincident with a synchronized mechanical breath and exceeding the previous unassisted spontaneous effort by more than 50{\%}. The incidence of augmented breaths was higher during SIMV (11.1 ± 7.7{\%}; P < 0.01) than during conventional IMV (5.1 ± 6.1{\%}). However, when the synchronized breaths were triggered late (200-300 msec) after the onset of inspiration, augmented breaths occurred no more frequently than during conventional IMV (6.0 ± 4.7{\%}). The incidence of augmented breaths correlated inversely with dynamic lung compliance (P = 0.014), but was not significantly influenced by a change in PEEP. Although inspiratory effort increased nearly three times during the augmented breaths, tidal volume increased only 12{\%}. The change in tidal volume was limited because the augmented effort reached its maximal negativity only approximately 500 ms after the beginning of the synchronized, mechanical breath and at a time when the mechanical breath had already ended. For this reason the augmented effort did not contribute significantly to minute ventilation, but only prolonged inspiration. Dynamic lung compliance did not change significantly after an augmented breath. The results indicate that augmented inspiratory efforts are more common in preterm neonates ventilated with SIMV than with conventional IMV, but do not contribute significantly to ventilation.",
keywords = "Augmented inspiration, Head's paradoxical reflex, Mechanical respiration, Newborn infant, Pulmonary function, Synchronized ventilation",
author = "Helmut Hummler and Tilo Gerhardt and Alvaro Gonzalez and Claure, {Nelson R} and Ruth Everett-Thomas and Eduardo Bancalari",
year = "1997",
month = "9",
day = "1",
doi = "10.1002/(SICI)1099-0496(199709)24:3<195::AID-PPUL5>3.0.CO;2-M",
language = "English",
volume = "24",
pages = "195--203",
journal = "Pediatric Pulmonology",
issn = "8755-6863",
publisher = "Wiley-Liss Inc.",
number = "3",

}

TY - JOUR

T1 - Increased incidence of sighs (augmented inspiratory efforts) during synchronized intermittent mandatory ventilation (SIMV) in preterm neonates

AU - Hummler, Helmut

AU - Gerhardt, Tilo

AU - Gonzalez, Alvaro

AU - Claure, Nelson R

AU - Everett-Thomas, Ruth

AU - Bancalari, Eduardo

PY - 1997/9/1

Y1 - 1997/9/1

N2 - A reflex resulting in a deep, sigh-like inspiratory effort (augmented breath) is frequently triggered during synchronized mechanical ventilation in preterm infants. We studied the incidence of augmented inspiratory efforts and their effect on ventilation and lung compliance during conventional IMV and synchronized IMV (SIMV) in 15 preterm neonates (GA 26.7 ± 1.5 wks (mean ± SD), BW 925 ± 222 g, age 1-8 days). Augmentation of spontaneous inspiratory effort was defined as an esophageal pressure deflection occurring coincident with a synchronized mechanical breath and exceeding the previous unassisted spontaneous effort by more than 50%. The incidence of augmented breaths was higher during SIMV (11.1 ± 7.7%; P < 0.01) than during conventional IMV (5.1 ± 6.1%). However, when the synchronized breaths were triggered late (200-300 msec) after the onset of inspiration, augmented breaths occurred no more frequently than during conventional IMV (6.0 ± 4.7%). The incidence of augmented breaths correlated inversely with dynamic lung compliance (P = 0.014), but was not significantly influenced by a change in PEEP. Although inspiratory effort increased nearly three times during the augmented breaths, tidal volume increased only 12%. The change in tidal volume was limited because the augmented effort reached its maximal negativity only approximately 500 ms after the beginning of the synchronized, mechanical breath and at a time when the mechanical breath had already ended. For this reason the augmented effort did not contribute significantly to minute ventilation, but only prolonged inspiration. Dynamic lung compliance did not change significantly after an augmented breath. The results indicate that augmented inspiratory efforts are more common in preterm neonates ventilated with SIMV than with conventional IMV, but do not contribute significantly to ventilation.

AB - A reflex resulting in a deep, sigh-like inspiratory effort (augmented breath) is frequently triggered during synchronized mechanical ventilation in preterm infants. We studied the incidence of augmented inspiratory efforts and their effect on ventilation and lung compliance during conventional IMV and synchronized IMV (SIMV) in 15 preterm neonates (GA 26.7 ± 1.5 wks (mean ± SD), BW 925 ± 222 g, age 1-8 days). Augmentation of spontaneous inspiratory effort was defined as an esophageal pressure deflection occurring coincident with a synchronized mechanical breath and exceeding the previous unassisted spontaneous effort by more than 50%. The incidence of augmented breaths was higher during SIMV (11.1 ± 7.7%; P < 0.01) than during conventional IMV (5.1 ± 6.1%). However, when the synchronized breaths were triggered late (200-300 msec) after the onset of inspiration, augmented breaths occurred no more frequently than during conventional IMV (6.0 ± 4.7%). The incidence of augmented breaths correlated inversely with dynamic lung compliance (P = 0.014), but was not significantly influenced by a change in PEEP. Although inspiratory effort increased nearly three times during the augmented breaths, tidal volume increased only 12%. The change in tidal volume was limited because the augmented effort reached its maximal negativity only approximately 500 ms after the beginning of the synchronized, mechanical breath and at a time when the mechanical breath had already ended. For this reason the augmented effort did not contribute significantly to minute ventilation, but only prolonged inspiration. Dynamic lung compliance did not change significantly after an augmented breath. The results indicate that augmented inspiratory efforts are more common in preterm neonates ventilated with SIMV than with conventional IMV, but do not contribute significantly to ventilation.

KW - Augmented inspiration

KW - Head's paradoxical reflex

KW - Mechanical respiration

KW - Newborn infant

KW - Pulmonary function

KW - Synchronized ventilation

UR - http://www.scopus.com/inward/record.url?scp=0030886595&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030886595&partnerID=8YFLogxK

U2 - 10.1002/(SICI)1099-0496(199709)24:3<195::AID-PPUL5>3.0.CO;2-M

DO - 10.1002/(SICI)1099-0496(199709)24:3<195::AID-PPUL5>3.0.CO;2-M

M3 - Article

C2 - 9330416

AN - SCOPUS:0030886595

VL - 24

SP - 195

EP - 203

JO - Pediatric Pulmonology

JF - Pediatric Pulmonology

SN - 8755-6863

IS - 3

ER -