PowerPoint Presentation (PDF) - Perfusion.com

Alicia Sievert, MS, CCP, Joseph Sistino, MS, MPA, CCP, Sean Wittorf
Medical University of South Carolina, Charleston, SC
March 10, 2011

Pulse Pressure > 15 mmHg
Defining PP
Energy Equivalent Pressure (EEP) (Shepard)
Ratio between the area beneath the hemodynamic power curve (∫fpdt)
and area beneath the pump flow curve (∫fdt) during each pulse cycle:
EEP = (∫fdpt)/(∫fdt)
where f = pump flow rate,
p = arterial pressure
dt = change in time at the end of flow and pressure cycles
The difference between EEP and MAP = the extra energy generated
(physiologic pulse ~10-12%)

Choosing the Right Equipment
Up to 80% of energy created is
dampened by circuit components
• Oxygenators with a lower
pressure drop
• Aortic cannulas with shorter
tips and a lower pressure drop
Wang et al. Hemodynamic Energy Delivery of the Pulsatile Flow in a
Simulated Pediatric Extracorporeal Circuit, ASAIO. 2009;55:96-99.

Common Settings on Roller Head Pumps
• Adults
• Peds
• BPM 80
• Amplitude 70-80%
• Base 20-30%
• BPM 100-150
• Amplitude 70%
• Base 30%
Initiated during XC
How to Pulse
May also use IABP set to internal 80 BPM during XC

Advantages of Pulsatile Perfusion
Better organ
preservation
SIRS
•Improved cerebral perfusion
•Promotion of metabolic
exchange
•↑ urine output
•↓ inotropic support/ Better
myocardial function
•↓ pulmonary edema
•↓ intubation times
•↓ lactate levels
• ↓ endothelial damage
• Lower C-reactive protein &
cytokine levels
• ↓ capillary leak
Endocrine
system
response
Temp
Management
• ↓ Plasma vasopressin
• ↓ Thyroid hormone
• ↓ Adrenocortical hormone
• ↓ Cortisol
• ↓ Cathecholamines
• ↓ Rennin & angiotensin II
• ↓ Thromboxane
• More even warming & cooling

Disadvantages of Pulsatile Perfusion
Difficulty
Hemolysis
Gaseous
microemboli
production
• Reluctant acceptance of surgical team
• Proper equipment – pumps,
oxygenators, cannulae
• Higher circuit pressure
• Cavitation during negative pressure
phase of pulse cycle

Purpose
To determine if there is a significant difference in
post-operative renal function with pulsatile
perfusion verses non-pulsatile perfusion during
cardiac surgery.

Methods
PubMed Search: (National Library of Medicine) 1990-present
• Keywords – “pulsatile perfusion, pulse, pulsatile flow
and cardiopulmonary bypass/cardiac surgery”
Inclusion Criteria: research articles were prospective, humans, paper
contained documented baseline demographics, outcome data included
renal function
Statistics: Meta-analysis using Comprehensive Meta-Analysis version 2.2
for Windows
• A random effects model was used when there was heterogeneity of effect sizes
was present

Outcome Variables
Demographics
• Pre-op Creatinine
• CPB Time
• XC Time
• MAP on CPB
Renal Function
• Creatinine
• Creatinine clearance
• BUN
• Lactate
• SVR

Results
A total of 298 articles were initially identified
Ten articles met the inclusion criteria (3 Ped, 7 Adult)
• Pulsatile Perfusion (PP), n = 708
• Nonpulsatile Perfusion (NP), n = 477

Articles Included
Article Peds/Adults Sample Size
(PP/NP)
Badner, 1992 Adults 27/26 Stockert
Method of Pulsatility
Louagie, 1992 Adults 50/50 Stockert 10-00-00
Poswal, 2004 Adults 50/50 Sarns 9000
Onorati, 2005 Adults 20/20 IABP
Alkan, 2006 Peds 25/25 Stockert S3
Alkan, 2007 Peds 151/64 Stockert S3
Onorati, 2007 Adults 50/50 IABP
Onorati, 2009a Adults 40/40 IABP
Onorati, 2009b Adults 87/71 IABP
Alkcevin, 2010 Peds 208/81 Stockert S3

Pre-op
Creatinine
(mg/dL)
CPB Time
(min)
XC Time
(min)
MAP
(mmHg)
Results - Demographics
PP
(mean)
NP
(mean)
Difference
in Means
SE Significance
0.83 0.85 -0.01 0.07 ns
103.65 104.23 0.11 0.1 ns
65.33 64.95 0.32 0.24 ns
67.4 69.2 -0.99 0.46 0.03
Difference in standardized means = PP-NP

Results – Post-op Renal Function
Articles n Difference
in Means
SE Significance
Creatinine 9 1132 -0.01 0.02 ns
BUN 6 415 0.68 0.53 ns
SVR 5 478 0.14 0.67 ns
CrCl 6 531 2.48 0.86 0.004
Difference in standardized means = PP-NP

Results – Renal Function
Post-operative creatinine clearance was significantly greater with pulsatile
perfusion (p=0.004)
Difference in standardized means = PP-NP
Favors NP Favors PP

Results – Lactate
There was a significant reduction in lactate levels in ICU with pulsatile
perfusion (p=0.012)
Difference in standardized means = PP-NP
Favors PP Favors NP

Conclusion
Pulsatile perfusion is beneficial in renal
preservation and should be considered, especially
for high risk patients
Most significant findings:
• Pulsatile perfusion results in
• Greater creatinine clearance
• Reduced post operative lactate levels

Limitations
• Included pediatric and adult studies
• Different methods of pulsatile flow between
studies
• Quantification of pulsatile perfusion not always
reported
• Publication bias is possible due to publication
of positive results

Alicia Sievert, MS, CCP, Joseph Sistino, MS, MPA, CCP, Sean Wittorf
Medical University of South Carolina, Charleston, SC
March 10, 2011

Non-pulsatile Perfusion Mode Pulsatile Perfusion Mode
Undar et al. Effects of perfusion mode on regional and global organ blood flow in a neonatal
piglet model. Ann Thorac Surg. 1999; 68: 1336-42.