J Thorac Cardiovasc Surg 2001 Jun;121(6):1179-86

Superior hepatic mitochondrial oxidation-reduction state in normothermic
cardiopulmonary bypass.

Hashimoto K, Sasaki T, Hachiya T, Onoguchi K, Takakura H, Oshiumi M, Takeuchi S.

Department of Cardiovascular Surgery, Saitama Cardiovascular and Respiratory
Center, Saitama-ken, Japan.

OBJECTIVE: This study is the first comparative investigation of hepatic blood
flow and oxygen metabolism during normothermic and hypothermic cardiopulmonary
bypass. 
METHODS: Twenty-four patients undergoing coronary bypass operations were
randomly divided into 2 groups according to their perfusion temperatures, either
normothermia (36 degrees C) or hypothermia (30 degrees C). The clearance of
indocyanine green was measured at 3 points. Arterial and hepatic venous ketone
body ratios (an index of mitochondrial redox potential) and hepatic venous
saturation were measured. 
RESULTS: Hepatic blood flow in both groups was
identical before, during, and after cardiopulmonary bypass (normothermia, 499
+/- 111, 479 +/- 139, and 563 +/- 182 mL/min, respectively; hypothermia, 476 +/-
156, 491 +/- 147, and 560 +/- 202 mL/min, respectively). The hepatic venous
saturation levels were significantly lower during cardiopulmonary bypass in the
normothermic group (normothermia, 41% +/- 13%; hypothermia, 61% +/- 18%; P
\.01), indicating a higher level of oxygen extraction use. The arterial ketone
body ratio in the hypothermic group decreased severely after the onset of
cardiopulmonary bypass (P <.01) and did not return to its subnormal value (>0.7)
until the second postoperative day. However, the reduction in arterial ketone
body ratio was less severe in the normothermic group. The difference in hepatic
venous ketone body ratios was more obvious, and the hepatic venous ketone body
ratios in the normothermic group were statistically superior to those of the
hypothermic group throughout the course (P <.05-.01). 
CONCLUSIONS: Normothermic
cardiopulmonary bypass provides adequate liver perfusion and results in a better
hepatic mitochondrial redox potential than hypothermic cardiopulmonary bypass.
Because arterial ketone body ratios reflect hepatic energy potential,
normothermia was considered to be physiologically more advantageous for hepatic
function.

 J Thorac Cardiovasc Surg 2001 Jun;121(6):1150-60

Cerebral injury during cardiopulmonary bypass: Emboli impair memory.

Fearn SJ, Pole R, Wesnes K, Faragher EB, Hooper TL, McCollum CN.

Department of Surgery, South Manchester University Hospitals, Manchester, United
Kingdom.

OBJECTIVES: Cognitive deficits occur in up to 80% of patients after cardiac
surgery. We investigated the influence of cerebral perfusion and embolization
during cardiopulmonary bypass on cognitive function and recovery. 
METHODS:
Cerebrovascular reactivity was measured in 70 patients before coronary
operations in which nonpulsatile bypass was used. Throughout the operations,
middle cerebral artery flow velocity and embolization were recorded by
transcranial Doppler and regional oxygen saturation was recorded by
near-infrared spectroscopy. Cognitive function was measured by a computerized
battery of tests before the operation and 1 week, 2 months, and 6 months after
surgery. Elderly patients undergoing urologic surgery served as controls.
RESULTS: Cerebrovascular reactivity was impaired preoperatively in 49 patients.
Median (interquartile range) regional cerebral oxygen saturation fell during
bypass by 10% (6%-15%), indicating increased oxygen extraction, whereas mean
middle cerebral flow velocity increased significantly by a median of 6 cm/s
(both P <.0001, Wilcoxon), suggesting increased arterial tone. More than 200
emboli were detected in 40 patients, mainly on aortic clamping and release, when
bypass was initiated, and during defibrillation. Cognitive function deteriorated
more in patients having cardiopulmonary bypass than in control patients having
urologic operations but recovered in most tests by 2 months. Measures of
cerebral perfusion (poor cerebrovascular reactivity, low arterial pressures, and
flow velocity in the middle cerebral artery) predicted poor attention at 1 week
(r = 0.3, P <.01, Spearman). Emboli were associated with memory loss (r = 0.3, P
<.02, Spearman). 
CONCLUSIONS: Cognitive deficits were common after
cardiopulmonary bypass. Occult cerebrovascular disease was more severe than
expected and predisposed to attention difficulties, whereas emboli caused memory
deficits. We believe this to be the first report of differing cognitive effects
from emboli and hypoperfusion.

Anesth Analg 2001 Jun;92(6):1370-6

The association of high jugular bulb venous oxygen saturation with cognitive
decline after hypothermic cardiopulmonary bypass.

Yoshitani K, Kawaguchi M, Sugiyama N, Sugiyama M, Inoue S, Sakamoto T, Kitaguchi
K, Furuya H.

Department of Anesthesiology, Nara Medical University, Nara, Japan.
nkenji@mva.biglobe.ne.jp

This study was conducted to investigate whether jugular bulb venous oxygen
saturation (SjVO(2)) predicted cognitive decline after cardiac surgery with
hypothermic cardiopulmonary bypass (CPB). We studied 35 patients undergoing
cardiac surgery. After the induction of anesthesia, a 5.5F fiberoptic oximetry
catheter was retrogradely inserted into the jugular bulb, and SjVO(2) and other
cerebral oxygenation variables were analyzed before, during, and after CPB. At
each point, an oxyhemoglobin dissociation curve was drawn, and the P(50) value
of jugular bulb venous blood was calculated by computer analysis. Cognitive
function was assessed with the revised version of Hasegawa's Dementia Scale and
the Benton Revised Visual Retention Test before and early after the operation.
In 15 patients (the Decline group), cognitive function was declined after
surgery, whereas it remained unchanged in 20 patients (the Normal group).
SjVO(2) was significantly higher and cerebral oxygen extraction was
significantly lower before and during CPB in the Decline group than in the
Normal group (P < 0.05). The oxygen pressure at an oxygen saturation of 50% was
significantly lower before and after CPB in the Decline group than in the Normal
group (P < 0.05). Logistic regression analysis showed that high SjVO(2) was a
predictor of cognitive decline after cardiac surgery. We conclude that high
SjVO(2) was associated with cognitive decline after cardiac surgery with
hypothermic CPB. 
IMPLICATIONS: Jugular bulb venous oxygen desaturation has been
suggested as a predictor of cognitive decline after cardiac surgery. However,
the clinical value of jugular bulb venous oxygen saturation (SjVO(2)) may be
limited during hypothermic cardiopulmonary bypass (CPB) when oxygen affinity to
hemoglobin is increased. This study shows that high SjVO(2) before and during
hypothermic CPB is a predictor of subsequent cognitive decline.

Eur J Cardiothorac Surg 2001 Jun;19(6):756-64

Cyclosporine A as a potential neuroprotective agent: a study of prolonged
hypothermic circulatory arrest in a chronic porcine model.

Hagl C, Tatton NA, Weisz DJ, Zhang N, Spielvogel D, Shiang HH, Bodian CA, Griepp
RB.

Department of Cardiothoracic Surgery, Mount Sinai School of Medicine, New York
University, One Gustave L. Levy Place, 10029, New York, NY, USA

Objective: To assess whether Cyclosporine A (CsA) or cycloheximide (CHX) can
reduce ischemia-induced neurological damage by blocking apoptotic pathways, we
assessed their effects on cerebral recovery in a chronic animal model of
hypothermic circulatory arrest (HCA). 
Methods: Twenty-eight pigs (28-33 kg)
underwent 90 min of HCA at 20 degrees C. In this blinded study, animals were
randomized to placebo (n=12), 5 mg/kg CsA (n=8), given intravenously before and
subcutaneously for 7 days after HCA, or a single dose of 1 mg/kg CHX (n=8),
given after weaning from cardiopulmonary bypass. Hemodynamics, intracranial
pressure (ICP) and neurophysiological data (EEG, SSEP) were assessed for 3 h
after HCA; early behavioral recovery was scored, and neurological/behavioral
evaluation (9=normal) was carried out daily until elective sacrifice on
postoperative day (POD) 7. Brains were selectively perfused and evaluated
histopathologically for apoptosis. 
Results: Basic hemodynamic data revealed no
differences between CsA or CHX and control groups. ICP was significantly lower
throughout rewarming (P=0.009) and reperfusion (P=0.05) in the CsA group. EEG
recovery 3 h after HCA was observed in four of eight CsA animals but in only 1
of 12 controls (P=0.11) and one of eight CHX animals; cortical SSEP recovery
also seemed faster in CsA animals, but failed to reach significance. Some early
recovery scores were significantly better in the CsA group, and daily behavioral
scores were consistently and significantly higher in the CsA-treated animals
from POD1 through POD4. 
Conclusions: The data indicate that treatment with
Cyclosporine A but not cycloheximide has a positive effect on cerebral recovery
following HCA. Whether CsA results in inhibition of neuronal apoptosis, and/or
inhibits release of cytokines and thereby reduces postischemic cerebral edema
remains to be elucidated. The neuroprotective effect of CsA, if confirmed in
further studies, would make its clinical application conceivable.

Am J Respir Crit Care Med 2001 Jun;163(7):1605-8

Comparative effects of red blood cell transfusion and increasing blood flow on
tissue oxygenation in oxygen supply-dependent conditions.

Linden PV, De Hert S, Belisle S, De Groote F, Mathieu N, D'Eugenio S, Julien V,
Huynh C, Melot C.

Department of Experimental Anesthesia, Erasme University Hospital, Brussels,
Belgium.

Red blood cell (RBC) transfusion is usually administered to improve oxygen
delivery (DO(2)) in order to sustain tissue oxygen demand. However, this
practice is not supported by firm clinical or experimental data. Using a
randomized two-period crossover design, this study compared the efficacy of
"fresh" RBC transfusion and increased blood flow to restore tissue oxygenation
in oxygen supply-dependent conditions. In 12 ketamine-anesthetized mongrel dogs
submitted to nonpulsatile normothermic cardiopulmonary bypass, DO(2) was reduced
by a progressive decrease in pump flow. DO(2) dependency was defined as an O(2)
uptake (V O(2)) decrease by more than 15% from baseline value. Then,
intervention consisted of a 40% increase in DO(2) obtained either by transfusion
of "fresh" dog's RBC (stored < 3 d) or by increase in pump flow. Animals
received both interventions sequentially in a random order, while O(2)
saturation was maintained constant. In O(2) supply-dependent conditions, rising
pump flow from 1.6 +/- 0.4 to 2.7 +/- 0.7 L/ min increased DO(2) from 5.4 +/-
1.1 to 9.0 +/- 1.3 ml/kg/min (p < 0.01) and V O(2) from 3.5 +/- 0.4 to 4.1 +/-
0.5 ml/kg/min (p = 0.02). "Fresh" RBC transfusion, which increased the
hemoglobin concentration from 6.4 +/- 0.9 to 11.1 +/- 1.3 g/dl, increased DO(2)
from 5.4 +/- 1.2 to 9.0 +/- 1.4 ml/kg/min (p < 0.01) and V O(2) from 3.6 +/- 0.4
to 4.1 +/- 0.5 ml/kg/min (p = 0.02). There was no difference in V O(2) resulting
from both interventions. In oxygen supply-dependent conditions, "fresh" RBC
transfusion and increased blood flow are equally effective in restoring tissue
oxygenation.

J Cardiovasc Surg (Torino) 2001 Jun;42(3):311-5

Conventional coronary artery bypass grafting: why women take longer to recover.

Ott RA, Gutfinger DE, Alimadadian H, Selvan A, Miller M, Tanner T, Hlapcich WL,
Gazzaniga AB.

Cardiothoracic Services, Anaheim Memorial Medical Center, Anaheim, CA, USA.

BACKGROUND: Recovery following successful coronary artery bypass grafting (CABG)
has been dramatically improved with the use of fast-track 
METHODS. Although data
exist that demonstrate a significant gender difference in survival following
CABG, little is known about factors influencing gender-specific recovery. This
report describes a series of consecutive patients undergoing isolated CABG to
determine gender-associated factors that may impact outcomes and recovery.
METHODS: Five hundred and seventeen consecutive patients underwent isolated CABG
utilizing cardiopulmonary bypass and were retrospectively reviewed. The outcomes
of 351 men in the study were compared to the group of 160 women. A rapid
recovery protocol focused on reduced cardiopulmonary bypass time, aggressive
preoperative intra-aortic balloon pump use, early extubation, perioperative
administration of corticosteroids and thyroid hormone, aggressive diuresis and
atrial fibrillation prevention was applied to all patients. 
RESULTS: The 30-day
mortality rate for the women was 4.2% (Parsonnet risk 16.3+/-9.0) compared with
3.4% (Parsonnet risk 9.9+/-7.5) for the men. There were no statistically
significant differences in the 30-day mortality rates or postoperative
complication rates between the women and men. The women, however, were found to
be older (71+/- years versus 65+/- years, p<0.001), and to have a higher
incidence of acute myocardial infarction (31% versus 20%, p<0.05), obesity (23%
versus 10%, p <0.05), diabetes (31% versus 22%, p<0.05), hypertension (65%
versus 48%, p<0.001), and symptomatic vascular disease (20% versus 12%, p<0.05).
The women required fewer bypass grafts (2.9 versus 3.5 grafts, p<0.001), and
consequently, had shorter cross and cardiopulmonary bypass times. Rapid recovery
with discharge before the fifth postoperative day was achieved in 30% of the
women, in comparison to 44% of the men (p<0.01). The postoperative hospital
length of stay was longer for the women in comparison to the men (7.2+/-7.1
versus 5.8+/-5.2 days, p<0.05). 
CONCLUSIONS: Women had similar operative
mortality and postoperative complication rates to men under a rapid recovery
protocol. However, women have a longer recovery interval compared to men, which
may be a reflection of their higher preoperative risk profile.

J Am Soc Echocardiogr 2001 Jun;14(6):595-600

Intraoperative contrast echocardiography with intravenous optison does not cause
hemodynamic changes during cardiac surgery.

Erb JM, Shanewise JS.

Department of Anesthesiology (J.M.E.), German Heart Institute Berlin; and the
Department of Anesthesiology (J.S.S.), Division of Cardiothoracic
Anesthesiology, Emory University School of Medicine, Atlanta, Ga.

BACKGROUND: The echocardiographic contrast agent Optison may be useful in
patients undergoing cardiac surgery. This study investigates its effects on
hemodynamics, cardiac performance, and oxygenation in this group of patients.
METHODS: Parameters of hemodynamic stability, cardiac performance, and
oxygenation were measured in 57 patients by transesophageal echocardiography,
electrocardiography, invasive arterial blood pressure and central venous
pressure monitoring, capnography, pulsoximetry, and pulmonary artery catheter
before and 5 and 10 minutes after an intravenous bolus of 0.3 mL of Optison.
RESULTS: No statistically significant differences in ST-segment changes, heart
rate, arterial and central venous pressure, peripheral oxygen saturation,
cardiac index, left ventricular ejection fraction, and regional wall motion were
seen 5 and 10 minutes after injection of Optison compared with baseline
parameters. 
CONCLUSIONS: Optison did not cause clinically important changes in
parameters of hemodynamic stability, cardiac performance, and oxygenation in our
patients. The intraoperative use of intravenous Optison appears to be safe in
patients undergoing cardiac surgery, including in the use of cardiopulmonary
bypass.

Curr Opin Pediatr 2001 Jun;13(3):220-6

Neonates with congenital heart disease.

Laussen PC.

Harvard Medical School and Cardiac Intensive Care Unit, Children's Hospital,
Boston, Massachusetts, USA.

Early reparative surgery in neonates and infants with congenital heart disease,
as opposed to initial palliation and later repair, is now commonplace. Changes
to the conduct of cardiopulmonary bypass, timing of surgery and surgical
techniques, and perioperative management substantially have reduced the
postoperative mortality and morbidity for these patients. The success of this
strategy of early reparative surgery now has been extended to the premature and
low-birth-weight newborn, and, along with this, new challenges to postoperative
care in the intensive care unit. However, the low mortality associated with
two-ventricle repairs has not been the experience in newborns undergoing
palliation for single-ventricle defects, in particular, hypoplastic left heart
syndrome. A number of articles regarding management of newborns with
single-ventricle defects have been published during the past 12 months, ranging
from classification, prenatal diagnosis, treatment options, and predictors of
both early and late outcome, which may provide a guide for patient management.
As mortality has declined, there has been an increased emphasis on identifying
indices that may predict outcome or morbidity both before and after surgery,
along with possible strategies to attenuate adverse clinical responses. The
inflammatory response to bypass is heightened in neonates and infants, and
several reports have addressed possible techniques for attenuating the response.
In addition, reports regarding the risk for necrotizing enterocolitis, the
utility of lactate as an index of systemic perfusion, potential markers of
myocardial and neurologic injury, and the use of mechanical support of the
circulation in newborns with congenital heart disease are summarized.

Neurosurgery 2001 Jun;48(6):1381-5

Resection of a giant intracranial dural arteriovenous fistula with the use of
low-flow deep hypothermic cardiopulmonary bypass after partial embolization:
technical case report.

Dufour H, Levrier O, Bruder N, Messana T, Grisoli F.

Department of Neurosurgery, University of Marseille, France. hdufour@ap-hm.fr

OBJECTIVE AND IMPORTANCE: To describe the surgical resection of a giant
intracerebral arteriovenous fistula with involvement of dura mater and
surrounding bone. Intraoperative bleeding was controlled by hypothermic
circulatory arrest. 
CLINICAL PRESENTATION: This 46-year-old woman complained of
persistent headache for 1 year; her diagnostic workup revealed the presence of
an arteriovenous fistula in the dura mater of the left temporal region fed by
the meningeal artery of the external and internal carotid arteries, with normal
run-off into Labbe's and Trolard's veins. Magnetic resonance imaging depicted a
Chiari I malformation that was most likely a result of insufficient cerebral
venous drainage.
 INTERVENTION: In preparation for surgery, staged embolization
of feeders from the left meningeal artery and the left occipital artery was
performed under controlled hypotension. This procedure failed to achieve a
significant reduction in flow because of the immediate recruitment of internal
branches of the internal carotid artery and dural branches of the right external
carotid artery. Surgical treatment was undertaken without further embolization.
Because of involvement of surrounding bone and the high risk of uncontrollable
bleeding, the procedure was carried out with the patient under deep hypothermic
cardiopulmonary bypass. Forty-five minutes of low flow (1.5 L/min) at 18 degrees
C allowed total resection of the involved dura mater and surrounding bone.
Postoperative recovery was marked by left brain edema that disappeared within 10
days. Findings on follow-up angiography were normal, and the patient was
discharged with no neurological deficit. 
CONCLUSION: Low-flow deep hypothermic
cardiopulmonary bypass can be used to control intraoperative bleeding for
surgical excision of a giant intracerebral dural arteriovenous fistula.