J Clin Anesth  2003 May;15(3):189-93 

Body Weight-Related ionized hypomagnesemia in pediatric patients undergoing
cardiopulmonary bypass for surgical repair of congenital cardiac defects.

Lu CY, Tan PH, Lin SH, Tsai SK, Lin SM, Mao CC, Yang LC.

Department of Anesthesiology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung
Hsien, Taiwan

To examine the serial time course of perioperative plasma ionized magnesium
(iMg(2+)) concentrations and to analyze the plasma iMg(2+) concentrations in
children with different body mass who were undergoing open-heart
surgery.Randomized, single-blinded study.University-affiliated hospital of an
academic medical institution.38 children undergoing open-heart surgery.Patients
were divided into three groups according to their body mass: Group 1 (n = 12)
<10 kg, Group 2 (n = 13) 10 kg to 20 kg, and Group 3 (n = 13) >20 kg.The
relationship of iMg(2+) among the three groups of different body mass were
analyzed at five different time intervals during the operation: induction of
anesthesia, 5 minutes and 30 minutes after the onset of cardiopulmonary bypass
(CPB), the beginning of rewarming, and the end of surgery.iMg(2+) levels at 5
minutes after onset of CPB in patients weighing less than 20 kg (Groups 1 and 2)
differed with those weighing more than 20 kg (Group 3) (p = 0.007 and 0.013).
However, there was no difference in the iMg(2+) levels between Groups 1 and 2 (p
= 0.993). In addition, iMg(2+) levels at 5 minutes after onset of bypass
correlated well (r(2) = 0.66) in children with body mass less than 20 kg.Low
levels of ionized magnesium is an important finding in patients at the onset of
CPB, which correlates well with the body mass of patients weighing less than 20
kg, and could be predicted by the regression curve. Based on these findings,
hypomagnesemia can be prevented during CPB.

Circulation  2003 May 19; [epub ahead of print] 

Combined Steroid Treatment for Congenital Heart Surgery Improves Oxygen Delivery
and Reduces Postbypass Inflammatory Mediator Expression.

Schroeder VA, Pearl JM, Schwartz SM, Shanley TP, Manning PB, Nelson DP.

Divisions of Cardiology, Cardiothoracic Surgery, Molecular Cardiovascular
Biology, and Critical Care Medicine, Cincinnati Children's Hospital, Cincinnati,
Ohio.

BACKGROUND: Steroid administration during cardiopulmonary bypass is thought to
improve cardiopulmonary function by modulating bypass-related inflammation. This
study was designed to compare preoperative and intraoperative methylprednisolone
(MP) to intraoperative MP alone with respect to postbypass inflammation and
clinical outcome. 

METHODS AND RESULTS: Twenty-nine pediatric patients undergoing
bypass procedures were randomly assigned to receive preoperative and
intraoperative MP (30 mg/kg 4 hours before bypass and in bypass prime, n=14) or
intraoperative MP only (30 mg/kg, n=15). Myocardial inflammatory mediator mRNA
expression was determined in paired atrial biopsies (before and after bypass) by
ribonuclease protection. Before and after bypass, serum IL-6 and IL-10 were
measured by ELISA. Postoperative outcome was assessed by intubation time, CICU
length of stay, fluid balance, arterio-venous O2 difference (DeltaA-VO2), and
inotrope requirements. Compared with intraoperative MP alone, combined
preoperative and intraoperative MP was associated with reduced myocardial mRNA
expression for IL-6, MCP-1, and ICAM-1 both before and after bypass (P<0.05).
Patients who received combined steroids had lower serum IL-6 and increased IL-10
at end-bypass (P<0.05), although differences were negligible by 24 hours.
Combined MP treatment was associated with reduced fluid requirements, lower body
temperature, and lower DeltaA-VO2 for the first 24 hours after surgery (P<0.05),
along with trends toward improvement in other clinical outcomes. 

CONCLUSIONS: Compared with intraoperative steroid treatment, combined preoperative and
intraoperative steroid administration attenuates inflammatory mediator
expression more effectively and is associated with improved indexes of O2
delivery in the first 24 hours after congenital heart surgery. These findings
need to be confirmed in a larger multicenter trial.

Eur J Cardiothorac Surg  2003 May;23(5):670-7 

Superior myocardial protection with nicorandil cardioplegia.

Steensrud T, Nordhaug D, Elvenes OP, Korvald C, Sorlie DG.

Department of Cardiothoracic and Vascular Surgery, University Hospital of North
Norway, Breivika, P.O. Box 102, N-9038, Tromso, Norway

OBJECTIVE: The ATP-sensitive potassium channel (K(ATP)) activator nicorandil
used as cardioplegic agent may protect the left ventricle during cardiac arrest.
Nicorandil in cold blood was compared with standard hyperkalemic blood and
crystalloid cardioplegia. 

METHODS: Twenty-one pigs were randomly assigned to
three groups: (1) cold hyperkalemic crystalloid (n=7); (2) cold hyperkalemic
blood (n=7); and (3) nicorandil as cardioplegia in cold blood (n=7). Left
ventricular mechanical performance, pressure-volume area (PVA) and myocardial
oxygen consumption (MVO(2)) were measured before and at 1 and at 2 h after 60
min of cold global ischemia on cardiopulmonary bypass using intraventricular
pressure-volume conductance catheters, coronary flow probes and O(2)-content
difference. 

RESULTS: The slope (M(w)) of the stroke work end-diastolic volume
relationship, the preload recriutable stroke work relationship, was unchanged
after ischemia in the nicorandil group, but was reduced to averaged 62.5%
(standard deviation 14) of baseline values in both hyperkalemic perfusions
(P<0.05). The slope of the MVO(2)-PVA relationship was unchanged after
nicorandil cardioplegia while the slope after hyperkalemic blood and crystalloid
cardioplegia increased with 33% (P<0.02) and 52% (P<0.02) of baseline values,
respectively. 

CONCLUSIONS: Nicorandil as sole cardioplegic agent in cold blood
given intermittently preserves left ventricular contractility and myocardial
energetics significantly better than traditional forms of cardioplegia after
cardiac arrest.

Chest  2003 May;123(5):1647-54 

Continuous tepid blood cardioplegia can preserve coronary endothelium and
ameliorate the occurrence of cardiomyocyte apoptosis.

Yeh CH, Wang YC, Wu YC, Chu JJ, Lin PJ.

Division of Thoracic and Cardiovascular Surgery, Chang Gung Memorial Hospital,
Chang Gung University, Taoyuan, Taiwan.

OBJECTIVE: In modern cardiac surgery, crystalloid or blood cardioplegic
solutions have been used widely for myocardial protection; however, ischemia
does occur during protection with intermittent infusion of cold crystalloid or
blood cardioplegic solutions. The present study was designed to evaluate the
effect of different cardioplegic methods on myocardial apoptosis and coronary
endothelial injury after global ischemia, cardiopulmonary bypass (CPB), and
reperfusion in anesthetized open-chest dogs. 

METHODS: The dogs were classified into five groups to identify the injury of myocardium and coronary endothelium:
group 1, normothermic CPB without cardiac arrest; group 2, hypothermic CPB with
continuous tepid blood cardioplegia, and with cardiac arrest; group 3,
hypothermic CPB with intermittent cold blood cardioplegia, and with cardiac
arrest; group 4, hypothermic CPB with intermittent cold crystalloid
cardioplegia, and with cardiac arrest; and group 5, sham-operated control group.
During CPB, cardiac arrest was achieved with different cardioplegia solutions
for 60 min, followed by reperfusion for 4 h before the myocardium and coronary
arteries were harvested. Coronary arteries were harvested immediately and
analyzed by scanning electron microscopy. Cardiomyocytic apoptosis was detected
using terminal deoxynucleotidyl transferase-mediated deoxyuridine
triphosphate-biotin nick end labeling, Western blot, and DNA ladder methods.
RESULTS: Regardless of the detection method used, significantly higher
percentages of apoptotic cardiomyocytes were found in group 3 and group 4 than
in other groups. Expression of caspase-3 correlated with increased apoptosis.
Scanning electron microscopy revealed severe endothelial injury of coronary
arteries in group 3 and group 4. 

CONCLUSION: These results point to an important explanation for the difference in cardiac recovery after hypothermic ischemia
and arrest with various cardioplegic solutions.

Chest  2003 May;123(5):1361-6 

Frequency, risk factors, and outcome of hyperlactatemia after cardiac surgery.

Maillet JM, Le Besnerais P, Cantoni M, Nataf P, Ruffenach A, Lessana A, Brodaty
D.

Cardiovascular and Thoracic Surgery Intensive Care Unit, Centre Cardiologique du
Nord, Saint-Denis, France.

STUDY OBJECTIVE: To determine the respective frequencies, risk factors, and
outcomes of no hyperlactatemia (NHL), immediate hyperlactatemia (IHL), or late
hyperlactatemia (LHL) > 3 mmol/L after cardiac surgery. 

DESIGN: Prospective and observational study. 

SETTING: Cardiac surgery ICU in a 130-bed private community
nonteaching hospital. 

PATIENTS: Consecutive patients (n = 325) undergoing
cardiopulmonary bypass (CPB) for cardiac surgery. 

INTERVENTION: None.

MEASUREMENTS: Arterial blood gas levels and lactate concentrations were measured
at ICU admission, 4 h after surgery, between 6 h and 16 h after surgery, and on
day 1. 

MAIN RESULTS: Sixty-seven patients (20.6%) had an IHL on ICU admission,
and 56 patients (17.2%) acquired LHL during their ICU stay. ICU mortality was
1.5% for NHL, 3.6% for LHL, and 14.9% for IHL groups (p < 0.0001). The three
groups differed significantly for elective surgery, type of operation, CPB
duration, intraoperative mean arterial pressure, and intraoperative and
postoperative use of vasopressor. Independent risk factors for IHL were
nonelective surgery, CPB duration, and intraoperative use of vasopressor.
Logistic regression identified hyperglycemia and epinephrine therapy for LHL as
postoperative risk factors. Receiver operating characteristic curves showed that
IHL more accurately predicted ICU mortality than LHL. 

CONCLUSIONS: Hyperlactatemia is common after cardiac surgery. A lactate threshold of 3 mmol/L
at ICU admission is able to identify a population at risk of morbidity and
mortality after cardiac surgery.

Ann Thorac Surg  2003 May;75(5):1565-71 

Mediastinitis in heart and lung transplantation: 15 years experience.

Abid Q, Nkere UU, Hasan A, Gould K, Forty J, Corris P, Hilton CJ, Dark JH.

Department of Cardiopulmonary Transplantation, Freeman Hospital,
Newcastle-upon-Tyne, United Kingdom. qumarabid@hotmail.com

BACKGROUND: Mediastinitis after sternotomy carries a very high mortality,
especially in patients receiving immunosuppressive treatment. 

METHODS: A retrospective analysis of the data for patients who had undergone
cardiopulmonary transplantation between May 1985 and December 2000 was
undertaken. A total of 776 patients had either a median sternotomy or a
transverse sternotomy through a clam-shell incision. Transplantations were as
follows: 591 heart (3 simultaneous heart and renal, and 1 heart and liver), 126
bilateral sequential lung, 57 heart-lung, 1 en bloc double-lung, and 1 heart and
single-lung. 

RESULTS: In all, 21 (2.7%) recipients had mediastinitis. Of these,
14 had heart, 3 heart-lung, and 4 bilateral lung transplantation. There were 18
median and 3 transverse sternotomies. There were 6 deaths (28.6%). Treatment
consisted of antibiotics alone in 2 patients and subxiphisternal drainage in
another 2 patients. The sternum was reopened in 17 (80.95%) patients, with
debridement and primary closure alone in 5 of these 17 patients and additional
irrigation in the other 12. Those who had resternotomy, debridement, and
substernal irrigation had a better outcome when compared with the outcomes of
other modes of treatment (1 death among 12 patients) (p = 0.06). Age,
cardiopulmonary bypass time, body mass index, time to diagnosis, and treatment
did not differ between those who survived and those who did not. 

CONCLUSIONS: Early aggressive debridement with substernal irrigation is the best mode of
treatment for patients with posttransplantation mediastinitis.

Ann Thorac Surg  2003 May;75(5):1527-30; discussion 1530-1 

Secundum ASD closure using a right lateral minithoracotomy: five-year experience
in 122 patients.

Doll N, Walther T, Falk V, Binner C, Bucerius J, Borger MA, Gummert JF, Mohr FW,
Kostelka M.

Heart Center, Department of Cardiac Surgery, University of Leipzig, Leipzig,
Germany.

BACKGROUND: Surgical closure of secundum atrial septal defect (ASD) is a
standard procedure associated with very low mortality and morbidity. We
evaluated outcomes in the era of catheter-based interventional closure and
minimally invasive techniques. 

METHODS: From May 1996, February 2002, 177 patients with a body weight of more than 30 kg underwent surgical ASD closure. A right lateral minithoracotomy (LMT) was used in 122 patients and a conventional
approach, in 55. Diagnoses included secundum ASD in 106 patients in the LMT
group and 40 in the conventional group, sinus venosus ASD in 13 patients in each
group, and status post interventional closure in 3 and 2 patients, respectively.
Mean age was 37 +/- 17 years in the LMT group and 43 +/- 20 years, in the
conventional group and mean body weight was 66 +/- 17 kg and 70 +/- 16 kg,
respectively. In the LMT group, femoral cannulation was performed for
cardiopulmonary bypass. 

RESULTS: Direct ASD closure was carried out in 67.2% of
patients in the LMT group and 58.2% of those in the conventional group. The
remaining patients had pericardial patch closure. There was one death: A patient
in the conventional group who required explantation of an Amplatzer device
because of infection died postoperatively. Average stay in the intensive care
unit was 1.2 +/- 0.5 days. Two patients required reoperation for residual ASD
after direct closure; 1 sustained a temporary neurological deficit that resolved
completely. On postoperative echocardiography, a minimal residual shunt was seen
in only 3 patients. All patients were in good clinical condition with improved
functional status at discharge from the hospital. 

CONCLUSIONS: Secundum ASD closure by LMT has become as standard and safe an operation as the conventional
technique and achieves good perioperative results and satisfactory long-term
outcomes. Thus LMT is an attractive option for patients who are not suitable for
closure using catheter-based devices.

Ann Thorac Surg  2003 May;75(5):1506-12 

Blood loss in infants and children for open heart operations: albumin 5% versus
fresh-frozen plasma in the prime.

Oliver WC Jr, Beynen FM, Nuttall GA, Schroeder DR, Ereth MH, Dearani JA, Puga
FJ.

Department of Anesthesiology, Mayo Foundation, Rochester, Minnesota 55905, USA.
william@mayo.edu

BACKGROUND: Infants and children undergoing cardiopulmonary bypass become
substantially hemodiluted secondary to the volume used to prime the oxygenator.
Fresh-frozen plasma has been included in the prime to lessen dilution of
clotting factors and correspondingly minimize blood loss and transfusions.

METHODS: We prospectively randomized 56 patients weighing 10 kg or less who
required cardiopulmonary bypass to receive either one unit of fresh-frozen
plasma or 200 mL of albumin 5% in the prime. After protamine administration,
samples for prothrombin time, fibrinogen, platelet count, and thromboelastogram
were obtained. Mediastinal chest tube drainage and transfusion requirements were
documented. 

RESULTS: There were no significant differences between groups
regarding demographic or surgical characteristics. Blood loss during the first
24 hours was similar in both groups, but total transfusions were significantly
greater in those who received fresh-frozen plasma instead of albumin 5% in the
prime (8.0 +/- 4.2 versus 6.1 +/- 4.5 U, respectively; p = 0.035). Post hoc
analyses suggest that for cyanotic patients and patients undergoing complex
operations, fresh-frozen plasma in the prime results in less blood loss than
albumin 5%. 

CONCLUSIONS: Substitution of albumin 5% for fresh-frozen plasma in
the prime of acyanotic patients weighing 10 kg or less who undergo noncomplex
operations requiring cardiopulmonary bypass significantly reduces perioperative
transfusions without increasing blood loss. Further investigation is needed to
determine whether increased blood loss is associated with increased transfusions
when albumin 5% is substituted for fresh-frozen plasma in the prime of infants
and children who are cyanotic or undergoing complex operations.

Cytometry  2003 May;53B(1):54-62 

Standardized immune monitoring for the prediction of infections after
cardiopulmonary bypass surgery in risk patients.

Strohmeyer JC, Blume C, Meisel C, Doecke WD, Hummel M, Hoeflich C, Thiele K,
Unbehaun A, Hetzer R, Volk HD.

Institute for Medical Immunology, Charite-Campus Mitte, Berlin, Germany.

BACKGROUND: Infections are the most common cause of late complications in
cardiopulmonary bypass (CPB) surgery patients, and are difficult to predict.
Here we studied the diagnostic value of a standardized immune monitoring program
based on recent advances in flow cytometry (exact quantification of
surface-marker expression) and cytokine determination (semiautomatic systems).

METHODS: CPB patients (56) at risk for complications (age >70 years and/or
preoperative left-ventricular ejection fraction < 25 %) were classified into
three groups: without (33), with suspected (14), and with confirmed (9)
infection. Applying the Quantibrite trade mark -system, we daily quantified the
expression of CD11b, CD64, CD71, CD86, and HLA-DR on monocytes/granulocytes.
Furthermore, the ex vivo secretion of tumor necrosis factor (TNF)-alpha as well
as the plasma interleukin (IL)-10 levels were determined by a semiautomatic
system. Ex vivo elastase release was measured by enzyme-linked immunosorbent
assay (ELISA). 

RESULTS: All patients showed signs of granulocyte activation and
monocyte deactivation. Monocytic HLA-DR and plasma IL-10 were the best markers
to discriminate patients with infection from those without as early as day 1.
Using a cutoff of 5792 HLA-DR molecules per cell, both sensitivity and negative
predictive value for patients who developed microbiologically confirmed
infection was 1.0, and the area under the curve (AUC) was 0.85. 

CONCLUSIONS: Our data suggest that a standardized immune monitoring at day 1 might be useful for
early discrimination of patients at elevated risk for infections. Cytometry Part
B (Clin. Cytometry) 53B:54-62, 2003. Copyright 2003 Wiley-Liss, Inc.