Skip to content

Advertisement

  • Meeting abstract
  • Open Access

Effects of PEEP and tidal volume on elastances and distribution of volume changes of the different chest wall compartments

  • 1,
  • 1,
  • 1,
  • 1,
  • 1,
  • 2,
  • 2 and
  • 1
Critical Care20004 (Suppl 1) :P121

https://doi.org/10.1186/cc841

  • Published:

Keywords

  • Public Health
  • Emergency Medicine
  • Volume Change
  • Volume Distribution
  • Chest Wall

Full text

We used optoelectronic plethysmography [1] to analyze six sedated and paralyzed ALI/ARDS patients receiving continuous positive pressure ventilation (CPPV) with different settings of PEEP (5, 10, 15 cmH2O) and tidal volume (TV, 300, 600, 900 ml). The aim of the present work is to study the effects of PEEP and TV on volume distribution in three different chest wall compartments (upper thorax, VUT, lower thorax, VLT and abdomen, VAB) and on their elastances (EUT, ELT and EAB, respectively) assessed by the end-inspiratory occlusion technique. Results are expressed in the table as mean ± SD.

We found that both PEEP and TV, but not their interaction, have an effect on volume distribution in the UT and AB (P<0.05). At increasing PEEP and TV, the increased abdominal and decreased upper thoracic contribution to inspired volume were associated to a decreased compliance of the UT. Finally, we found significant (P<0.001) exponential relationships between UT and AB contributions to TV and EUT.

We conclude that at high PEEP and TV, the elastance of the upper thorax decreases and it causes a more `abdominal' distribution of TV.

Table

PEEP (cmH2O)

TV (ml)

Vut (% TV)

Vlt (% TV)

Vab (% TV)

Eut (cmH2O/L)

Elt (cmH2O/L)

Eab (cmH2O/L)

5

300

39.4± 14.4

10.1± 5.3

50.5± 14.0

76.9± 26.3

378.1± 266.9

63.6± 37.6

5

600

32.5± 9.5

11.1± 3.3

56.4± 11.4

76.8± 25.3

211.4± 63.6

45.3± 23.4

5

900

27.7± 7.6

11.1± 4.0

61.2± 9.1

92.3± 47.8

180.3± 73.7

36.3± 21.2

10

300

31.7± 8.8

10.6± 2.3

57.7± 9.9

69.0± 18.8

220.5± 87.6

46.9± 39.9

10

600

26.7± 6.8

10.1± 3.0

63.1± 8.5

85.2± 19.6

230.1± 70.0

39.4± 14.5

10

900

24.9± 6.2

11.1± 3.2

64.0± 8.2

96.7± 7.4

190.9± 51.0

31.9± 11.2

15

300

26.2± 5.4

10.4± 4.5

63.4± 7.9

92.2± 10.2

344.3± 231.0

34.1± 12.1

15

600

24.8± 6.7

11.5± 3.0

63.7± 8.2

112.9± 20.9

254.7± 84.9

42.6± 11.1

15

900

23.7± 6.4

10.8± 3.6

65.5± 9.0

126.7± 33.1

251.5± 50.5

43.5± 17.6

Authors’ Affiliations

(1)
Dipartimento di Bioingegneria, Politecnico di Milano, Italy
(2)
Istituto di Anestesia e Rianimazione, Ospedale Maggiore IRCCS, Politecnico di Milano, Milano, Italy

References

  1. Aliverti A, Dellacà R, Pelosi P, Chiumello D, Pedotti A, Gattinoni L: Optoelectronic plethysmography in intensive care patients. Am J Resp Crit Care Med, in press.Google Scholar

Copyright

Advertisement