PMID- 35546125
OWN - NLM
STAT- MEDLINE
DCOM- 20220624
LR  - 20220808
IS  - 1522-1601 (Electronic)
IS  - 0161-7567 (Linking)
VI  - 133
IP  - 1
DP  - 2022 Jul 1
TI  - Graded lower body negative pressure induces intraventricular negative pressures 
      and incremental diastolic suction: a pressure-volume study in a porcine model.
PG  - 20-26
LID - 10.1152/japplphysiol.00110.2022 [doi]
AB  - Lower body negative pressure (LBNP) is a tool to study compensatory mechanisms to 
      central hypovolemia for decades. However, the underlying hemodynamic mechanisms 
      were mostly assessed noninvasively and remain unclear. We hypothesized that 
      incremental LBNP reduces diastolic filling and thereby affects left ventricular 
      (LV) diastolic suction (DS). Here, we investigated the impact of graded LBNP at 
      three different levels of seal as well as during beta-adrenergic stimulation by 
      invasive pressure-volume (PV) analysis. Eight Landrace pigs were instrumented 
      closed-chest for PV assessment. LBNP was applied at three consecutive locations: 
      I) cranial, 10 cm below xiphoid process; II) medial, half-way between cranial and 
      caudal; III) caudal, at the iliac spine. Level III was repeated under dobutamine 
      infusion. At each level, baseline measurements were followed by application of 
      incremental LBNP of -15, -30, and -45 mmHg. LBNP induced varying degrees of 
      preload-dependent hemodynamic changes, with cranial LBNP inducing more pronounced 
      effects than caudal. According to the Frank-Starling mechanism, graded LBNP 
      progressively reduced LV stroke volume (LV SV) following a decrease in LV 
      end-diastolic volume. Negative intraventricular minimal pressures were observed 
      during dobutamine-infusion as well as higher levels of LBNP. Of note, incremental 
      LV negative pressures were accompanied by increasing DS volumes, derived by 
      extrapolating the volume at zero transmural pressure, the so-called equilibrium 
      volume (V(0)), related to LV SV. In conclusion, graded preload reduction via LBNP 
      shifts the PV loop to smaller volumes and end-systolic volume below V(0), which 
      induces negative LV pressures and increases LV suction. Accordingly, LBNP-induced 
      central hypovolemia is associated with increased DS.NEW & NOTEWORTHY This study 
      examined the effects of incremental lower body negative pressure (LBNP) from -15 
      to -45 mmHg on hemodynamic regulation using invasive pressure-volume assessment 
      in closed-chest pigs. Graded preload reduction via LBNP induces negative left 
      ventricular (LV) pressures while increasing LV suction and thus allowing the 
      ventricle to eject below the equilibrium volume at the end of systole. 
      Accordingly, LBNP-induced central hypovolemia is associated with increased 
      diastolic suction.
FAU - Berboth, Leonhard
AU  - Berboth L
AUID- ORCID: 0000-0002-4896-2095
AD  - Department of Internal Medicine and Cardiology, Charite-Universitatsmedizin 
      Berlin, Berlin, Germany.
FAU - Zirngast, Birgit
AU  - Zirngast B
AD  - Department of Cardiac Surgery, Medical University of Graz, Graz, Austria.
FAU - Manninger, Martin
AU  - Manninger M
AD  - Department of Cardiology, University Clinic of Medicine, Medical University of 
      Graz, Graz, Austria.
FAU - Steendijk, Paul
AU  - Steendijk P
AD  - Department of Cardiology, Leiden University Medical Center, Leiden, The 
      Netherlands.
FAU - Tschope, Carsten
AU  - Tschope C
AD  - Department of Internal Medicine and Cardiology, Charite-Universitatsmedizin 
      Berlin, Berlin, Germany.
FAU - Scherr, Daniel
AU  - Scherr D
AD  - Department of Cardiology, University Clinic of Medicine, Medical University of 
      Graz, Graz, Austria.
FAU - Hinghofer-Szalkay, Helmut G
AU  - Hinghofer-Szalkay HG
AD  - Institute of Physiology, Centre of Physiological Medicine, Medical University of 
      Graz, Graz, Austria.
FAU - Goswami, Nandu
AU  - Goswami N
AUID- ORCID: 0000-0002-6704-0723
AD  - Institute of Physiology, Centre of Physiological Medicine, Medical University of 
      Graz, Graz, Austria.
AD  - Mohammed Bin Rashid University of Medicine and Health Science, Dubai Healthcare 
      City, Dubai, United Arab Emirates.
FAU - Petersen, Lonnie G
AU  - Petersen LG
AUID- ORCID: 0000-0002-5155-9651
AD  - Department of Radiology, University of California, San Diego, California.
AD  - Mechanical and Aerospace Engineering, University of California, San Diego, 
      California.
FAU - Machler, Heinrich
AU  - Machler H
AD  - Department of Cardiac Surgery, Medical University of Graz, Graz, Austria.
FAU - Alogna, Alessio
AU  - Alogna A
AUID- ORCID: 0000-0001-5988-2720
AD  - Department of Internal Medicine and Cardiology, Charite-Universitatsmedizin 
      Berlin, Berlin, Germany.
AD  - Berlin Institute of Health, Charite-Universitatsmedizin Berlin, Berlin, Germany.
AD  - DZHK (German Centre for Cardiovascular Research), Partner Site Berlin, Berlin, 
      Germany.
LA  - eng
GR  - Berlin Institute of Health (BIH)/
GR  - K.H. Tscheliessnigg foundation/
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20220512
PL  - United States
TA  - J Appl Physiol (1985)
JT  - Journal of applied physiology (Bethesda, Md. : 1985)
JID - 8502536
RN  - 3S12J47372 (Dobutamine)
SB  - IM
MH  - Animals
MH  - Dobutamine
MH  - Hemodynamics
MH  - Hypovolemia
MH  - *Lower Body Negative Pressure
MH  - Stroke Volume/physiology
MH  - Suction
MH  - Swine
MH  - *Ventricular Function, Left/physiology
OTO - NOTNLM
OT  - diastolic suction
OT  - invasive hemodynamics
OT  - lower body negative pressure
OT  - pressure-volume loops
EDAT- 2022/05/13 06:00
MHDA- 2022/06/25 06:00
CRDT- 2022/05/12 09:03
PHST- 2022/05/13 06:00 [pubmed]
PHST- 2022/06/25 06:00 [medline]
PHST- 2022/05/12 09:03 [entrez]
AID - 10.1152/japplphysiol.00110.2022 [doi]
PST - ppublish
SO  - J Appl Physiol (1985). 2022 Jul 1;133(1):20-26. doi: 
      10.1152/japplphysiol.00110.2022. Epub 2022 May 12.