Perfusion Literature

J Thorac Cardiovasc Surg  2003 Mar;125(3 Pt 1):625-32 

Deep hypothermic circulatory arrest and global reperfusion injury: Avoidance by
making a pump prime reperfusate-A new concept.

Allen BS, Veluz JS, Buckberg GD, Aeberhard E, Ignarro LJ.

Division of Cardiovascular Surgery, University of California at Los Angeles
Medical Center, Los Angeles, Calif, and The Heart Institute for Children, Hope
Children's Hospital, Oak Lawn, Ill.

OBJECTIVE: We sought to determine whether damage after deep hypothermic
circulatory arrest can be diminished by changing pump prime components when
reinstituting cardiopulmonary bypass. METHODS: Fifteen piglets (2-3 months old)
were cooled to 19 degrees C by using the alpha-stat pH strategy. Five were
cooled and rewarmed without ischemia (control animals), and the other 10 piglets
underwent 90 minutes of deep hypothermic circulatory arrest. Of these, 5 were
rewarmed and reperfused without altering the cardiopulmonary bypass circuit
blood prime. In the other 5 animals, the bypass blood prime was modified
(leukocyte depleted, hypocalcemic, hypermagnesemic, pH-stat, normoxic, mannitol,
and an Na(+)/H(+) exchange inhibitor) during circulatory arrest before starting
warm reperfusion. Oxidant injury was assessed on the basis of conjugated dienes,
vascular changes on the basis of endothelin levels, myocardial function on the
basis of cardiac output and dopamine need, lung injury on the basis of pulmonary
vascular resistance and oxygenation, and cellular damage on the basis of release
of creatine kinase and aspartate aminotransferase. Neurologic assessment (score
0, normal; score 500, brain death) was done 6 hours after discontinuing
cardiopulmonary bypass. RESULTS: Compared with animals undergoing
cardiopulmonary bypass without ischemia (control animals), deep hypothermic
circulatory arrest without modification of the reperfusate produced an oxidant
injury (conjugated dienes increased 0.78 vs 1.71 absorbance (Abs) 240 nmol/L per
0.5 mL, P <.001 vs control animals), depressed cardiac output (6.0 vs 4.0 L/min,
P <.05 vs control subjects), prolonged dopamine need (P <.001 vs control
subjects), elevated pulmonary vascular resistance (74% vs 197%, P <.05 vs
control subjects), reduced oxygenation (P <.01 vs control subjects), increased
neurologic injury (56 vs 244, P <.001 vs control subjects), and increased
release of creatine kinase (2695 vs 6974 U/L, P <.05 vs control subjects),
aspartate aminotransferase (144 vs 229 U/L), and endothelin (1.02 vs 2.56 pg/mL,
P <.001 vs control subjects). Conversely, the oxidant injury was markedly
limited (conjugated dienes of 0.85 +/- 0.09 Abs 240 nmol/L per 0.5 mL, P <.001
vs unmodified pump prime) with modification of cardiopulmonary bypass prime,
resulting in increased cardiac output (5.1 +/- 0.8 L/min), minimal dopamine need
(P <.001 vs unmodified pump prime), no increase in pulmonary vascular resistance
(44% +/- 31%, P <.01 vs unmodified pump prime) or endothelin levels (0.64 +/-
0.15 pg/mL, P <.001 vs unmodified pump prime), complete recovery of oxygenation
(P <.01 vs unmodified pump prime), reduced neurologic damage (144 +/- 33, P <.05
vs unmodified pump prime), and lower release of aspartate aminotransferase (124
+/- 23 U/L, P <.05 vs unmodified pump prime) and creatine kinase (3366 +/- 918,
P <.05 vs unmodified pump prime). CONCLUSIONS: A global reperfusion injury after
deep hypothermic circulatory arrest was identified and changed. The injury is
mediated by oxygen-derived free radicals, resulting in organ and endothelial
dysfunction. Modification of global organ and endothelial damage is achieved by
modifying the blood prime in the cardiopulmonary bypass circuit to deliver a
controlled global reperfusate when reinstituting bypass.

J Thorac Cardiovasc Surg  2003 Mar;125(3 Pt 1):491-9 

Novel cerebral physiologic monitoring to guide low-flow cerebral perfusion
during neonatal aortic arch reconstruction.

Andropoulos DB, Stayer SA, McKenzie ED, Fraser CD Jr.

Divisions of Pediatric Cardiovascular Anesthesiology and Congenital Heart
Surgery, Texas Children's Hospital and Baylor College of Medicine, Houston, Tex.

OBJECTIVE: This study was undertaken to describe the combined measurement of
cerebral blood flow velocity and cerebral oxygen saturation as a guide to bypass
flow rate for regional low-flow perfusion during neonatal aortic arch
reconstruction. METHODS: Data were prospectively collected from 34 patients
undergoing neonatal aortic arch reconstruction with regional low-flow perfusion.
Cerebral oxygen saturation and blood flow velocity were measured by
near-infrared spectroscopy and transcranial Doppler ultrasonography,
respectively, throughout cardiopulmonary bypass. After cooling to 17 degrees C
to 22 degrees C, baseline values of cerebral oxygen saturation and blood flow
velocity were recorded during full-flow bypass. Regional low-flow perfusion was
instituted for aortic arch reconstruction, and bypass flow rate was adjusted to
maintain cerebral oxygen saturations and blood flow velocities within 10% of
baseline recorded during cold full-flow bypass. Cerebral oxygen saturations and
blood flow velocities were recorded again after repair during full-flow
hypothermic bypass. Bypass flow during regional low-flow perfusion was recorded,
as were arterial pressure and blood gas data. One-way repeated measures analysis
of variance was used to determine differences in values during regional low-flow
perfusion relative to baseline and after perfusion. RESULTS: A mean bypass flow
of 63 mL/(kg x min) was required to maintain cerebral oxygen saturations and
blood flow velocities within 10% of baseline. Mean arterial pressure had a poor
correlation with the required bypass flow rate (r(2) = 0.006 by linear
regression analysis). Fourteen of 34 patients had a cerebral oxygen saturation
of 95% during regional low-flow perfusion, placing them at risk for cerebral
hyperperfusion if the cerebral oxygen saturation had been used alone to guide
bypass flow. Pressure was detected in the umbilical or femoral artery catheter
(mean 12 mm Hg) in all patients during regional low-flow perfusion. CONCLUSIONS:
Cerebral blood flow velocity, as determined by transcranial Doppler
ultrasonography, adds valuable information to cerebral oxygen saturation data in
guiding bypass flow during regional low-flow perfusion. Its most important use
may be prevention of cerebral hyperperfusion during periods with high
near-infrared spectroscopic saturation values.

Ann Thorac Surg  2003 Mar;75(3):931-4 

Cannulation of the axillary artery for cardiopulmonary bypass: safeguards and
pitfalls.

Sinclair MC, Singer RL, Manley NJ, Montesano RM.

Division of Cardiothoracic Surgery, Department of Surgery, Lehigh Valley
Hospital, Allentown, Pennsylvania 18105-1556, USA. sally.lutz@lvh.com

BACKGROUND: The ascending aorta is the customary site for arterial cannulation
for cardiopulmonary bypass. Favorable experience at our institution and
elsewhere using axillary artery cannulation in treating type A aortic
dissections has caused us to broaden our indications for using this site for
arterial cannulation for cardiopulmonary bypass. METHODS: Medical records,
operative notes, and perfusion records were reviewed in all patients in whom the
axillary artery was cannulated directly or by a graft for cardiopulmonary bypass
from January 1, 2000 through August 30, 2002. RESULTS: Seventy-five patients
underwent axillary artery cannulation during the 32-month interval. Eleven
patients had ascending aortic dissections, 20 had extensively diseased ascending
aortas, and 44 were individuals undergoing repeat cardiac procedures. The right
axillary artery was used in 72 patients and the left in 3. In 16 patients the
artery was cannulated directly, and in 59 the arterial cannula was inserted into
a prosthetic graft that had been anastomosed to the axillary artery. Axillary
artery cannulation was satisfactory in 95% (71 of 75) of the cases in which it
was used. CONCLUSIONS: Cannulation of the axillary artery for cardiopulmonary
bypass is a dependable approach for procedures including reoperations, aortic
dissections, and extensively diseased ascending aortas.

Ann Thorac Surg  2003 Mar;75(3):926-30 

A double-blind randomized trial: prophylactic vasopressin reduces hypotension
after cardiopulmonary bypass.

Morales DL, Garrido MJ, Madigan JD, Helman DN, Faber J, Williams MR, Landry DW,
Oz MC.

Department of Surgery, Columbia University, College of Physicians and Surgeons,
New York, New York 10032, USA. dlm36@columbia.edu

BACKGROUND: Inhibition of angiotensin-converting enzyme (ACE) predisposes
patients to vasodilatory hypotension after cardiopulmonary bypass (CPB). This
hypotension has been correlated with arginine vasopressin deficiency and can be
corrected by its replacement. In patients receiving ACE inhibition, we
investigated whether initiation of vasopressin before CPB would diminish
post-CPB hypotension and catecholamine use by avoiding vasopressin deficiency.
METHODS: Cardiac surgical patients on ACE inhibitor therapy were randomized to
receive vasopressin (0.03 U/min) (n = 13) or an equal volume of normal saline (n
= 14) starting 20 minutes before CPB. RESULTS: Vasopressin did not change
pre-CPB mean arterial pressure or pulmonary artery pressure. After CPB, the
vasopressin group had a lower peak norepinephrine dose than the placebo group
(4.6 +/- 2.5 versus 7.3 +/- 3.5 microg/min, p = 0.03), a shorter period on
catecholamines (5 +/- 6 versus 11 +/- 7 hours, p = 0.03), fewer hypotensive
episodes (1 +/- 1 versus 4 +/- 2, p < 0.01), and a shorter intensive care unit
length of stay (1.2 +/- 0.4 versus 2.1 +/- 1.4 days, p = 0.03). CONCLUSIONS: In
this cohort, prophylactic administration of vasopressin, at a dose without a
vasopressor effect pre-CPB, reduced post-CPB hypotension and vasoconstrictor
requirements, and was associated with a shorter intensive care unit stay.

Blood Coagul Fibrinolysis  2003 Mar;14(2):175-9 

Correlation between thrombin potential and bleeding after cardiac surgery in
adults.

Davidson SJ, Burman JF, Philips SM, Onis SJ, Kelleher AA, De Souza AC, Pepper
JR.

Departments of Haematology, Anaesthetics and Surgery, Royal Brompton Hospital,
London, UK.

We used a sensitive assay to measure thrombin potential in 20 patients who
underwent cardiopulmonary bypass surgery for coronary artery bypass grafts. We
measured coagulation factors II, V, VII, VIII and X. Blood loss was measured as
the total amount in the mediastinal drains in the first 24 h postoperatively.
Thrombin potential was median 107 nmol/l.min (range 62-181) preoperatively and
median 46 nmol/l.min (range 19-120) postoperatively. Coagulation factors II, V,
VII,VIII and X were within normal limits preoperatively. Factor II fell from 77
IU/dl preoperatively to 37 IU/dl at 120 min postoperatively. Factor V fell from
85 IU/dl preoperatively to 61 IU/dl postoperatively. Factor VII fell from 91
IU/dl to 66 IU/dl postoperatively. Factor VIII was 128 IU/dl preoperatively and
127 IU/dl postoperatively. Factor X fell from 90 IU/dl preoperatively to 50
IU/dl postoperatively. Total blood loss in 24 h in the mediastinal drains
postoperatively was mean 673 ml, median 650 ml (range 250-2000). Reduction in
thrombin potential correlated inversely with postoperative blood loss, = -0.75
(Spearman correlation). The fall in the thrombin potential correlated with the
prothrombin level ( = 0.75) and factor X ( = 0.47).

Crit Care Med  2003 Mar;31(3):758-64 

Experience with percutaneous venoarterial cardiopulmonary bypass for emergency
circulatory support.

Schwarz B, Mair P, Margreiter J, Pomaroli A, Hoermann C, Bonatti J, Lindner KH.

OBJECTIVE Mechanical circulatory support can maintain vital organ perfusion in
patients with cardiac failure unresponsive to standard pharmacologic treatment.
The purpose of the current study was to report complication and survival rates
in patients supported with emergency percutaneous venoarterial cardiopulmonary
bypass because of prolonged cardiogenic shock or cardiopulmonary arrest.DESIGN
Retrospective clinical study.SUBJECTS A total of 46 patients supported with
venoarterial cardiopulmonary bypass, 25 because of cardiogenic shock
unresponsive to pharmacologic therapy and 21 because of cardiopulmonary arrest
unresponsive to standard advanced cardiac life support.RESULTS In 41 of the 46
patients (89%), stable extracorporeal circulation was established; in five
patients (11%), femoral cannulation was accomplished only after a surgical
cutdown. A total of 28 patients were weaned from cardiopulmonary bypass (19 of
25 patients with cardiogenic shock vs. 9 of 21 patients with cardiopulmonary
arrest, =.03), and 13 patients had long-term survival (10 of 25 patients with
cardiogenic shock vs. 3 of 21 patients with cardiopulmonary arrest, =.1).
Complications directly related to the use of cardiopulmonary bypass were found
in 18 patients (39%), major complications related to femoral cannulation being
the most common single cause for bypass-associated morbidity (eight patients,
17%)CONCLUSIONS Long-term survival rates after emergency percutaneous
cardiopulmonary bypass are encouraging in patients with an underlying
cardiocirculatory disease amenable to immediate corrective intervention
(angioplasty, surgery, transplantation).

Anesth Analg  2003 Mar;96(3):644-50, table of contents 

Comparison of alpha-stat and pH-stat cardiopulmonary bypass in relation to
jugular venous oxygen saturation and cerebral glucose-oxygen utilization.

Kiziltan HT, Baltali M, Bilen A, Seydaoglu G, Incesoz M, Tasdelen A, Aslamaci S.

Department of Cardiothoracic Surgery, Baskent University, Adana Medical Center,
Adana, Turkey. tkiziltan@turk.net

Jugular venous oxygen saturation (SJVO(2)) reflects the balance between cerebral
blood flow and metabolism. This study was designed to compare the effects of two
different acid-base strategies on jugular venous desaturation (SJVO(2) <50%) and
cerebral arteriovenous oxygen-glucose use. We performed a prospective,
randomized study in 52 patients undergoing cardiopulmonary bypass (CPB) at 27
degrees C with either alpha-stat (n = 26) or pH-stat (n = 26) management. A
retrograde internal jugular vein catheter was inserted, and blood samples were
obtained at intervals during CPB. There were no differences in preoperative
variables between the groups. SJVO(2) was significantly higher in the pH-stat
group (at 30 min CPB: 86.2% +/- 6.1% versus 70.6% +/- 9.3%; P < 0.001). The
differences in arteriovenous oxygen and glucose were smaller in the pH-stat
group (at 30 min CPB: 1.9 +/- 0.82 mL/dL versus 3.98 +/- 1.12 mL/dL; P < 0.001;
and 3.67 +/- 2.8 mL/dL versus 10.1 +/- 5.2 mL/dL; P < 0.001, respectively). All
episodes of desaturation occurred during rewarming, and the difference in the
incidence of desaturation between the two groups was not significant. All
patients left the hospital in good condition. Compared with alpha-stat, the
pH-stat strategy promotes an increase in SJVO(2) and a decrease in arteriovenous
oxygen and arteriovenous glucose differences. These findings indicate an
increased cerebral supply with pH-stat; however, this strategy does not
eliminate jugular venous desaturation during CPB. IMPLICATIONS: A prospective,
randomized study in 52 patients during cardiopulmonary bypass revealed that
pH-stat increased jugular venous oxygen saturation and decreased arteriovenous
oxygen-glucose differences. There was no difference in the incidence of jugular
venous desaturation. These findings suggest an increased cerebral blood flow
with no protection against jugular venous desaturation during pH-stat.

Ann Thorac Surg  2003 Mar;75(3):906-12 

Is kidney function altered by the duration of cardiopulmonary bypass?

Boldt J, Brenner T, Lehmann A, Suttner SW, Kumle B, Isgro F.

Department of Anesthesiology and Intensive Care Medicine, Klinikum der Stadt
Ludwigshafen, Ludwigshafen, Germany. boldtj@gmx.net

BACKGROUND: Cardiopulmonary bypass (CPB) is considered responsible for kidney
damage. By using sensitive markers of kidney damage we assessed whether the
length of CPB influences kidney function. METHODS: In a prospective study, 50
consecutive cardiac operation patients with CPB times of less than 70 minutes
were compared with 50 consecutive patients showing CPB times of more than 90
minutes. Aside from creatinine clearance and fractional excretion of sodium,
urine concentrations of N-acetyl-beta-D-glucosaminidase, alpha1-microglobulin,
glutathione transferase-pi, and glutathione transferase-alpha were measured
after induction of anesthesia at the end of the operation, and on the first and
second postoperative days in the intensive care unit. RESULTS: CPB times were 58
+/- 12 minutes and 116 +/- 18 minutes, respectively. Hemodynamics, volume
replacement, and use of catecholamines during cardiopulmonary bypass (CPB) were
without significant differences between groups. Concentrations of all
kidney-specific proteins increased significantly after CPB, showing the highest
significant increases in the CPB more than 90 minutes group (eg, glutathione
transferase-alpha CPB > 90 minutes from 3.0 +/- 1.0 to 12.9 +/- 2.9 microg/L;
glutathione transferase-alpha CPB < 70 minutes from 2.4 +/- 0.5 to 5.5 +/- 1.2
microg/L). By the second postoperative day, urine concentrations of
kidney-specific proteins had returned to almost baseline in the CPB less than 70
minutes patients, but remained slightly elevated in the other group.
CONCLUSIONS: Patients with CPB times more than 90 minutes showed more pronounced
kidney damage than patients with CPB times less than 70 minutes as assessed by
sensitive kidney-specific proteins. Whether patients with preexisting renal
dysfunction undergoing prolonged CPB times would profit from renal protection
strategies needs to be elucidated.

Med Sci Monit  2003 Mar;9(3):CR109-13 

Experience in using three different minimally invasive approaches in cardiac
operations.

Wang WL, Cai KC, Zeng WS, Jiang RC.

Department of Cardiothoracic Surgery, Guangzhou General Military Hospital.

BACKGROUND: In order to reach a clear understanding of minimally invasive
approaches in cardiac operations, the authors review clinical experience in
using three such approaches: inferior partial median sternotomy, right
anterolateral minor thoracotomy, and the right parasternal approach.
MATERIAL/METHODS: Sternotomy and the three different minimally invasive
approaches were applied in and 2431 and 323 patients respectively. The
approaches were selected according to the circumstances of the individual case.
Both external and internal cardiac structures were observed during the
operations. The length of the incision, the postoperative drainage, operative
time, and cardiopulmonary bypass time were investigated. The postoperative
complications occurring after minimally invasive approaches were observed.
RESULTS: In inferior partial median sternotomy, all structures except for the
ascending aorta could be exposed well. In right anterolateral minor thoracotomy,
only the structures on the right side of the heart could be exposed, but the
mitral valve could also be exposed well. The exposure of the right parasternal
approach was similar to that of right anterolateral minor thoracotomy. There
were statistically significant differences between sternotomy and the minimally
invasive approaches in terms of incision length and postoperative drainage, but
no difference in operative time and cardiopulmonary bypass time. The
postoperative complications of MIAs included air embolism (n=3), chest pain
(n=9), chest wall malacia (n=1), rib fracture (n=2), and sternum fracture (n=2).
The total incidence of complications in minimally invasive approaches was 5.3%.
CONCLUSIONS: The minimally invasive approaches can have satisfactory clinical
results if the approaches are correctly chosen and performed.

Crit Care Med  2003 Mar;31(3):758-64 

Experience with percutaneous venoarterial cardiopulmonary bypass for emergency
circulatory support.

Schwarz B, Mair P, Margreiter J, Pomaroli A, Hoermann C, Bonatti J, Lindner KH.

OBJECTIVE Mechanical circulatory support can maintain vital organ perfusion in
patients with cardiac failure unresponsive to standard pharmacologic treatment.
The purpose of the current study was to report complication and survival rates
in patients supported with emergency percutaneous venoarterial cardiopulmonary
bypass because of prolonged cardiogenic shock or cardiopulmonary arrest.DESIGN
Retrospective clinical study.SUBJECTS A total of 46 patients supported with
venoarterial cardiopulmonary bypass, 25 because of cardiogenic shock
unresponsive to pharmacologic therapy and 21 because of cardiopulmonary arrest
unresponsive to standard advanced cardiac life support.RESULTS In 41 of the 46
patients (89%), stable extracorporeal circulation was established; in five
patients (11%), femoral cannulation was accomplished only after a surgical
cutdown. A total of 28 patients were weaned from cardiopulmonary bypass (19 of
25 patients with cardiogenic shock vs. 9 of 21 patients with cardiopulmonary
arrest, =.03), and 13 patients had long-term survival (10 of 25 patients with
cardiogenic shock vs. 3 of 21 patients with cardiopulmonary arrest, =.1).
Complications directly related to the use of cardiopulmonary bypass were found
in 18 patients (39%), major complications related to femoral cannulation being
the most common single cause for bypass-associated morbidity (eight patients,
17%)CONCLUSIONS Long-term survival rates after emergency percutaneous
cardiopulmonary bypass are encouraging in patients with an underlying
cardiocirculatory disease amenable to immediate corrective intervention
(angioplasty, surgery, transplantation).