TOP TEN SELECTED PAPERS - July 2008

1

Heart Lung Circ. 2008 Jul 25. [Epub ahead of print]

Does Combined Antegrade-Retrograde Cardioplegia Have Any Superiority Over
Antegrade Cardioplegia?

Radmehr H, Soleimani A, Tatari H, Salehi M.

Cardiac Surgery Ward, Imam Khomeini Hospital, Medical Sciences/University of
Tehran, Iran.

BACKGROUND: In a prospective randomised clinical study we assessed and compared
antegrade vs. combined antegrade-retrograde cardioplegia in patients who
underwent elective coronary artery by pass grafting. METHODS: Between March 2006 
and January 2007, 87 consecutive patients were randomly divided into two groups. 
Group A (n=45) received antegrade cold (4 degrees C) blood cardioplegia. Besides 
antegrade cardioplegia, Group B (n=42) received continuous retrograde
cardioplegia passively by gravitational force. The need for cardiac support
during and after cardiopulmonary bypass, post-operative morbidity, ICU stay,
hospital stay and mortality were compared in two groups. RESULTS: There was no
significant difference between the two groups in gender, age and pre-operative
ejection fraction. Sixteen patients in Group A (35.5%) and eight patients in
Group B (19%) needed inotropic support while weaning off cardiopulmonary bypass
(p=0.04). Four patients in Group A (8.9%) and two patients in Group B (4.8%)
needed intra-aortic balloon pump (p=0.44) in the ICU. We found no statistically
important difference between the two groups in post-operative morbidity and
mortality. CONCLUSIONS: Retrograde continuous infusion of cardioplegia by
gravitational force combined with antegrade cardioplegia, provides satisfactory
myocardial protection and eliminates the need for inotropic support compared with
antegrade technique alone.

Interact Cardiovasc Thorac Surg. 2008 Jul 31. [Epub ahead of print]

Aprotinin's effect on blood product transfusion in off-pump bilateral lung
transplantation.

Balsara KR, Morozowich ST, Lin SS, Davis RD, Phillips-Bute BG, Hartwig MG, Appel 
JZ, Welsby IJ.

Duke University, Durham, NC, USA.

In lung transplants necessitating cardiopulmonary bypass (CPB), aprotinin has
been shown to decrease transfusion requirements. More recently, off-pump
transplantation has become the standard of care. The efficacy of aprotinin use in
this population has yet to be definitively examined. We completed a retrospective
review of all adult OP-BOLTs performed between January 2000 and January 2006 at a
single university center (n=215). Aprotinin use was determined by the attending
anesthesiologist or surgeon. It was administered at the time of induction. The
primary outcome was total blood products utilized in terms of units transfused
during post-operative days 0, 1 and 2. One-hundred and one patients received
aprotinin and 114 did not. An overall analysis of all of the patients in this
study demonstrated a trend towards statistical significance for reduced total
blood product transfusion for the aprotinin group compared to the non-aprotinin
group (p=0.13). A subgroup analysis was performed in relation to each diagnosis. 
The use of aprotinin was associated with a significant reduction in
peri-operative total blood products transfused in COPD patients (p=0.03)
undergoing OP-BOLT. Subgroup analysis demonstrated that the use of aprotinin in
the COPD population did result in a statistically significant decrease in total
blood products transfused, specifically the total number of units of packed red
blood cells given. These findings suggest that aprotinin administration should be
considered for all patients undergoing OP-BOLT to reduce exposure to blood
products and potential immune sensitization and infectious complications.
Keywords: Blood loss; Lung transplantation; Postoperative complications;
Aprotinin adverse effects; Blood transfusion.

Eur J Cardiothorac Surg. 2008 Jul 28. [Epub ahead of print]

High colloid oncotic pressure priming of cardiopulmonary bypass in neonates and
infants: implications on haemofiltration, weight gain and renal function.

Loeffelbein F, Zirell U, Benk C, Schlensak C, Dittrich S.

Department of Paediatric Cardiology and Congenital Heart Disease, University
Children's Hospital, Mathildenstrasse 1, D-79106 Freiburg, Germany.

Objective: To evaluate the influence of high colloid oncotic pressure (COP)
priming of cardiopulmonary bypass (CPB) on fluid balances, haemofiltration,
capillary leakage and renal function in neonates and infants. Methods: Twenty
neonates or infants underwent heart surgery using CPB and were randomised in two 
groups. For group 1 (FFP-group) a blood priming with fresh frozen plasma (FFP,
low oncotic pressure) was chosen, for group 2 (HA-group) a blood priming
containing FFP and human albumin 20% (HA) to realise higher oncotic pressures was
substituted. All patients were monitored before, during and 6h after CPB. We
measured weights, fluid balances, transfusion volumes, colloid oncotic pressures,
inflammatory parameters (c-reactive protein, interleukin-6, interleukin-8,
thrombocytes, leucocytes) and renal function (creatinine clearances, renal
protein losses). Results: Patient's demographics and operational procedures were 
comparable in both groups with no further differences in operation procedures
regarding palliation or correction. Colloid oncotic pressures of the priming
solutions were higher in the HA-group (28mmHg+/-4.9) than in the FFP-group
(6mmHg+/-1.3, p<0.001). Relative weight gain as a marker of capillary leakage in 
the HA-group (2%+/-4.5) was significantly lower 6h post CPB than in the FFP-group
(8%+/-8.0, p=0.015). Haemofiltration rates were higher in the HA-group
(569ml+/-197 vs 282ml+/-157, p=0.002) on CPB. There were no differences of
creatinine clearances 6h after the end of CPB. Renal protein losses were elevated
in both groups without any inter-group differences during and 6h after CPB.
Conclusion: Addition of concentrated human albumin to priming fluids in
paediatric cardiac surgery leads to less weight gain even after CPB.
Supplementing paediatric patients undergoing cardiac surgery with concentrated
human albumin does not affect renal function more severely than in paediatric
patients undergoing cardiac surgery on CPB with blood priming.

Am J Kidney Dis. 2008 Jul 21. [Epub ahead of print]

Urinary Neutrophil Gelatinase-Associated Lipocalin and Acute Kidney Injury After 
Cardiac Surgery.

Wagener G, Gubitosa G, Wang S, Borregaard N, Kim M, Lee HT.

Department of Anesthesiology, College of Physicians and Surgeons, Columbia
University, New York, NY.

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) is proposed as an
early marker of kidney injury. We report the association of urinary NGAL with
indexes of intraoperative renal hypoperfusion (cardiopulmonary bypass time and
aortic cross-clamp time) and acute kidney injury (AKI) after adult cardiac
surgery. STUDY DESIGN: Diagnostic test accuracy. SETTING & PARTICIPANTS: Adult
cardiac surgical patients (n = 426) in a single center from 2004 to 2006. INDEX
TEST: Urinary NGAL immediately and 3, 18, and 24 hours after cardiac surgery,
using an enzyme-linked immunosorbent assay. REFERENCE TEST OR OUTCOME: Serum
creatinine-based definition for AKI (increase in serum creatinine from
preoperative values by >50% or >0.3 mg/dL within 48 hours). RESULTS: Mean urinary
NGAL level was 165 +/- 663 (SD) ng/mL preoperatively, peaked immediately after
cardiac surgery at 1,490 +/- 102 ng/mL, and remained significantly higher 3, 18, 
and 24 hours after surgery. 85 patients (20%) developed AKI. Areas under the
receiver operating characteristic curve for urinary NGAL immediately after and 3,
18, and 24 hours later as a predictor for AKI were 0.573 (95% confidence interval
[CI], 0.506 to 0.640), 0.603 (95% CI, 0.533 to 0.674), 0.611 (95% CI, 0.544 to
0.679), and 0.584 (95% CI, 0.510 to 0.657), respectively. Urinary NGAL, but not
serum creatinine, level correlated significantly with cardiopulmonary bypass and 
aortic cross-clamp times. Areas under receiver operating characteristic curves
for cardiopulmonary bypass time and aortic cross-clamp time to predict AKI were
0.592 (95% CI, 0.518 to 0.666) and 0.593 (95% CI, 0.523 to 0.665), respectively. 
LIMITATIONS: Limited sensitivity of changes in serum creatinine levels for kidney
injury. CONCLUSIONS: Urinary NGAL has limited diagnostic accuracy to predict AKI 
defined by change in serum creatinine after cardiac surgery.

ASAIO J. 2008 Jul-Aug;54(4):432-5.

"Stolen" blood flow: effect of an open arterial filter purge line in a simulated 
neonatal CPB model.

Wang S, Miller A, Myers JL, Undar A.

Department of Pediatrics, Penn State Milton S. Hershey Medical Center, Penn State
College Medicine, Penn State Children's Hospital, Hershey, Pennsylvania
17033-0850, USA.

The purpose of this study was to evaluate the effect of different flow rates and 
pressures on the degree of shunting of blood flow by the arterial filter purge
line in a simulated neonatal cardiopulmonary bypass circuit. The circuit was
primed with heparinized bovine blood (hematocrit 24%) and postfilter pressure was
varied from 60-180 mm Hg (20 mm Hg increments) using a Hoffman clamp. Trials were
conducted at flow rates ranging from 200-600 ml/min (100 ml/min increments).
During trials conducted at a postfilter pressure of 60 mm Hg, 42.6% of blood flow
was shunted through the purge line at a flow rate of 200 ml/min, whereas only
12.8% of flow was diverted at a flow rate 600 ml/min. During trials conducted at 
a postfilter pressure of 180 mm Hg, 82.8% of blood flow at 200 ml/min and 25.9%
of blood flow at 600 ml/min was diverted through the open arterial purge line.
The results of this study confirm that a significant amount of flow is diverted
away from the patient when the arterial purge line is open. Shunting of blood
flow through the arterial purge line could result in less effective tissue
perfusion, particularly at low flow rates and high postfilter pressures. To
minimize hypoperfusion injury, a flow probe (distal to the arterial filter) may
be used to monitor real-time arterial flow in the setting of an open arterial
filter purge line.

ASAIO J. 2008 Jul-Aug;54(4):416-22.

Delivery of gaseous microemboli with vacuum-assisted venous drainage during
pulsatile and nonpulsatile perfusion in a simulated neonatal cardiopulmonary
bypass model.

Wang S, Baer L, Kunselman AR, Myers JL, Undar A.

Department of Pediatrics, Penn State Milton S. Hershey Medical Center, Penn State
College Medicine, Penn State Children's Hospital, Hershey, Pennsylvania
17033-0850, USA.

This study investigated delivery of gaseous microemboli (GME) with
vacuum-assisted venous drainage (VAVD) at various flow rates and perfusion modes 
in a simulated neonatal cardiopulmonary bypass (CPB) model. Four transducers
(postpump, postoxygenator, postfilter, and venous line) of the emboli detection
and classification (EDAC) quantifier were inserted into the CPB circuit to detect
and classify GME. Four negative pressures (0, -15, -30, and -45 mm Hg), 3 flow
rates (750, 1,000, and 1,250 ml/min), and 2 perfusion modes (pulsatile and
nonpulsatile) were tested. After injecting 10 ml air into the venous line via an 
18G needle, 2-minute segments of data were recorded simultaneously through 4
transducers. This entire process was repeated 6 times for each unique combination
of pressure, flow rate, and perfusion mode, yielding a total of 144 experiments. 
Independent of perfusion mode and flow rate, the use of VAVD with higher negative
pressures delivered significantly more GME at the postpump site. There was no
difference in delivery at the postfilter site. The majority of GME were trapped
by the Capiox Baby-RX hollow-fiber membrane oxygenator. Compared with
nonpulsatile flow, pulsatile flow transferred more GME at the postpump site at
all 3 flow rates. Our results suggest that VAVD with higher negative pressures,
increased flow rates, and pulsatile flow could deliver more GME at the postpump
site when a fixed volume air is introduced into the venous line. The Emboli
Detection and Classification Quantifier is a sensitive tool for the detection and
classification of GME as small as 10 microns in this simulated neonatal model.

J Cardiothorac Surg. 2008 Jul 12;3(1):45.

Hydroxyethyl starch versus Ringer solution in cardiopulmonary bypass prime
solutions (a randomized controlled trial).

Tiryakioglu O, Yildiz G, Vural H, Goncu T, Ozyazicioglu A, Yavuz S.

Department of Cardiovascular Surgery, Bursa Yuksek Ihtisas Education and Research
Hospital, Bursa, Turkey. tiryaki64@hotmail.com.

ABSTRACT: BACKGROUND: In our study we compared the Ringer solution, which is the 
standard prime solution of our department, with the HES (Hydroxyethyl starch)
130-0.4 solution, which can be a potential alternative prime solution with an
indispensable material for the cardio-pulmonary bypass applications. METHODS: 140
patients undergoing to CABG (Coronary Artery Bypass Graft surgery) were
electively enrolled to the study. 1500 ml Ringer solution + 200 ml mannitol + 60 
ml sodium bicarbonate + 150 U/kg heparin was used as a prime solution to start
cardiopulmonary by-pass in 70 patients which was defined as group 1. On the other
hand, 1500 ml HES 130 - 0.4 + 200 ml mannitol + 60 ml sodium bicarbonate + 150
U/kg heparin was used as a prime solution in 70 patients in group 2. RESULTS: INR
(International Normalized Ratio), urea levels and blood platelet counts were
significantly different between the groups. INR level was higher in group 1,
while blood urea and creatinine levels and platelet count were higher in group 2 
at the end of the 12th and 24nd hours postoperatively (p = 0.001).In this study, 
it was shown that the usage of HES 130-0.4 as a prime solution did not have
negative effect on postoperative INR level, platelet count, the need for
transfusion and the amount of drainage, despite the negative opinions that
similar solutions caused coagulation disorders. Another interesting result of the
study was that blood platelet count at 24th hour was statistically significantly 
higher in group 2 (p = 0.001). CONCLUSION: HES 130-0.4 solution is an alternative
colloidal solution which can be used as the prime solution or as a mixture with
the crystalloids in cardio-pulmonary bypass applications.

Am J Emerg Med. 2008 Jul;26(6):649-54.

Utstein style study of cardiopulmonary bypass after cardiac arrest.

Tanno K, Itoh Y, Takeyama Y, Nara S, Mori K, Asai Y.

Critical Care and Trauma Center, Caress Alliance Nikko Memorial Hospital, Muroran
051-8501, Japan. tanno@sapmed.ac.jp

OBJECTIVE: The aim of this study is to describe the effect emergency
cardiopulmonary bypass (CPB) for resuscitation on the survival rate of patients. 
METHODS: The study population was composed of persons 16 years or older who had
out-of-hospital cardiac arrest and were transferred to the Sapporo Medical
University Hospital from the scene between January 1, 2000, and September 30,
2004. Children younger than 16 years and persons who were dead were excluded.
Data were collected according to the Utstein style. Survival rates and cerebral
performance category were analyzed using chi(2) analysis for the patients with
presumed cardiac etiology. Cardiopulmonary bypass was applied to patients who
showed no response with standard advanced cardiac life support. The interval from
collapse and other noncardiac etiologies were considered criteria for exclusion. 
RESULTS: Of the 919 patient medical records reviewed, CPB was performed in 92
patients. Of the 919 patients, 398 were of presumed cardiac etiology (n = 66 for 
CPB), 48 patients survived, and 24 patients (n = 7 for CPB) had a good cerebral
outcome (cerebral performance category score 1). With CPB, the rate of survival
at 3 months increased significantly (22.7% vs 9.9%, P < .05), but the rate of
good cerebral outcome (10.6% vs 5.1%, P = .087) showed a positive trend.
CONCLUSION: The use of CPB for arrest patients was associated with reduced
mortality. It did not increase good neurologic outcome significantly. Still, 7
cases with intact central nervous system would have been lost without CPB.

J Card Surg. 2008 Jul-Aug;23(4):288-93.

Avecor trillium oxygenator versus noncoated monolyth oxygenator: a prospective
randomized controlled study.

Vanden Eynden F, Carrier M, Ouellet S, Demers P, Forcillo J, Perrault LP,
Pellerin M, Bouchard D.

Department of Cardiac Surgery, Erasmus Hospital, Free University of Brussels,
Belgium.

OBJECTIVES: The surface coating of a synthetic surface is currently investigated 
to decrease the harmful effects of cardiopulmonary bypass (CPB). This study was
designed to study the effects of the surface coating of a hollow fiber membrane
oxygenator on coagulation, inflammation markers, and clinical outcomes. The
biomaterials used to coat the membrane include heparin, polyethylene oxide chains
(PEO), and sulfate/sulfonate groups. The coated membrane was compared to an
uncoated oxygenator made of polypropylene. METHODS: Two hundred patients who were
scheduled to undergo valve repair and/or replacement surgery with or without
coronary surgery were enrolled in the study. The patients were randomized to
undergo CPB with either the Avecor oxygenator with Trillium (Medtronic,
Minneapolis, MN, USA), a biopassive surface, or the Monolyth (Sorin, Irvine, CA, 
USA) oxygenator without coating. The primary and secondary endpoints were the
differences between these oxygenators in regard to patients' biochemistry,
coagulation profiles, inflammatory mediators, and clinical outcomes, including
blood loss and neurological events. RESULTS: There were no differences between
the two groups in terms of biochemistry, coagulation profile, inflammatory
mediator release, and blood loss. Five patients in the Avecor group showed
clinical evidence of a stroke confirmed with computerized tomography (CT) scan
imaging, and none in the noncoated oxygenator group. CONCLUSION: The oxygenator
Avecor offers similar results in terms of inflammation and coagulation profiles
and blood loss during valvular surgery compared to a standard uncoated control
oxygenator. The rate of neurological events was unusually elevated in the former 
group of patients, with only speculative explanation at this point. Further
studies are warranted to clarify this aspect.

Circulation. 2008 Jul 8;118(2):113-23.

Inadequate blood glucose control is associated with in-hospital mortality and
morbidity in diabetic and nondiabetic patients undergoing cardiac surgery.

Ascione R, Rogers CA, Rajakaruna C, Angelini GD.

Bristol Heart Institute, University of Bristol, Bristol, United Kingdom.

BACKGROUND: Derangement of glucose metabolism after surgery is not specific to
patients with diabetes mellitus. We investigated the effect of different degrees 
of blood glucose control (BGC) on clinical outcomes after cardiac surgery.
METHODS AND RESULTS: We analyzed 8727 adults operated on between April 1996 and
March 2004. The highest blood glucose level recorded over the first 60 hours
postoperatively was used to classify patients as having good (<200 mg/dL),
moderate (200 to 250 mg/dL), or poor (>250 mg/dL) BGC; 7547 patients (85%) had
good, 905 (10%) had moderate, and 365 (4%) had poor BGC. Patients with inadequate
BGC were more likely to present with advanced New York Heart Association class,
congestive heart failure, hypertension, renal dysfunction, and ejection fraction 
<50% (P0