Download Coronary Sinus Catheter Placement

Coronary Sinus Catheter Placement*
Assessment of Placement Criteria and Cardiac
Complications
Chris J. M. Langenberg, MD; Henk G. Pietersen, MD; Gijs Geskes, MD;
Anton J. M. Wagenmakers, MD, PhD; Peter B. Soeters, MD, PhD; and
Marcel Durieux, MD, PhD
Study objectives: To evaluate the placement and complications of a coronary sinus (CS) catheter
in human subjects.
Design: Sixty-two CS catheters inserted in patients scheduled for coronary artery bypass graft
surgery (CABG).
Setting: University hospital, anesthesia and cardiothoracic surgery departments.
Patients: Sixty-two patients without valvular or concomitant diseases undergoing CABG.
Interventions: CS fluoroscopy, measurements of CS flow, CS oxygen saturation, and CS distal tip
pressure before incision, after incision, 20 min after aortic cross-clamp release (X-off), 50 min
after X-off, 2 h after X-off, 4 h after X-off, and 6 h after X-off.
Results: In 57 patients (92%), we achieved successful CS catheter placement. In five patients (8%),
CS catheter positioning was not possible. Of the 57 CS catheters placed, dislocation occurred
during the operation in six patients (11%) and postoperatively in three patients (6%). Cardiac
complications of CS catheter placement occurred in nine patients (15%). Four patients (6%)
acquired hemopericardium. Three of these patients had a small hematoma in the right ventricle.
In two other patients, contrast medium appeared in the right ventricular wall during catheterization. No hemodynamic signs of these complications were detected clinically. Irregular heart
rhythm was observed in only three patients. CS blood oxygen saturation ranged from 40 to 60%.
CS flow amounted to 3% of cardiac output. Variations in CS flow paralleled changes in cardiac
output.
Conclusions: A CS catheter is a useful tool for clinical human cardiac research; however, the
placement of a CS catheter can cause minor myocardial damage in > 10% of patients.
Importantly, this damage may not be clinically evident, but only observed after thoracotomy. CS
oxygen saturation, CS flow, distal tip pressure, and fluoroscopy are reliable tools to assess a safe
and correct positioning of the CS catheter.
(CHEST 2003; 124:1259 –1265)
Key words: coronary artery bypass graft surgery; coronary sinus catheterization; coronary sinus flow; myocardial damage
Abbreviations: CABG ⫽ coronary artery bypass graft surgery; CS ⫽ coronary sinus; CVP ⫽ central venous pressure;
ECC ⫽ extracorporeal circulation; Finj ⫽ flow rate of injection; Tb ⫽ blood temperature; Ti ⫽ temperature of the
infused saline solution; Tm ⫽ temperature of the saline solution and blood mixture; X-off ⫽ aortic cross-clamp release
sinus (CS) drains 95% of the venous
T hebloodcoronary
of the myocardial muscle into the right
atrium, while the remaining 5% of myocardial venous flow drains through the thebesian vessels.1,2 In
1971, Ganz et al3 described a thermodilution technique to measure total CS blood flow. In human
metabolic studies of the heart, it is necessary to
*From the Department of Anesthesiology (Dr. Langenberg),
Jeroen Bosch Ziekenhuis, Hertogenbosch; Departments of Surgery (Drs. Pietersen and Soeters), Thoracic Surgery (Dr.
Geskes), and Human Biology (Dr. Wagenmakers), University
Hospital Maastricht; and Department of Anesthesiology (Dr.
Durieux), University of Maastricht, The Netherlands.
Manuscript received April 23, 2002; revision accepted February
27, 2003.
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obtain myocardial venous blood samples, which is
only possible via cannulation of the CS. Substrate
concentrations in arterial and CS blood, in combination with the measured CS flow, yield information
about the myocardial use of substrates and oxygen.4
The measured CS temperature during cardiac surgery provides another monitoring tool for determination of hypothermic protection in combination
Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (e-mail:
[email protected]).
Correspondence to: Chris J. M. Langenberg, MD, Jeroen Bosch
Ziekenhuis, Department of Anesthesiology, Postbus 90153, 5200
ME’s Hertogenbosch, The Netherlands; e-mail: [email protected]
CHEST / 124 / 4 / OCTOBER, 2003
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1259
with cardioplegic solutions. The flow in the CS
correlates with cardiac output, mean arterial pressure, and the flow through the coronary arteries, and
varies with the myocardial requirement for oxygen5,6;
therefore, the technique of CS cannulation is useful,
and at times essential, in studies of the cardiovascular system in humans.
Information about this technique is important,
because the coronary venous system is increasingly
used for left ventricular or biventricular pacing in
patients with severe heart failure,7 and for ablating
posteroseptal accessory neural pathways by means of
a venous approach and radiofrequency energy.8 According to the literature to date, most complications
occur during insertion of the CS catheter via the
internal jugular vein.9 They include placement in a
false route, accidental arterial puncture, and perforation of the upper lung.10 During insertion of the
catheter into the heart, dysrrhythmias and perforation of the atrium and/or right ventricle are possible,
which may result in a cardiac tamponade11 and
pericardial effusion.8 Little is known about the incidence of these cardiac complications, since they may
be clinically silent.
Measurements of CS flow may be influenced by
catheter position12; therefore, verification of correct
placement is essential. A number of criteria (CS
oxygen saturation, CS flow, distal tip pressure, and
fluoroscopy) have been suggested, but not verified,
as indicators of adequate placement. Criteria for
correct placement of the catheter are important, as
Figure 1. Anteroposterior fluoroscopic view of a coronary sinus
catheter in the human heart showing the coronary sinus catheter
(A), pulmonary artery catheter (B), coronary sinus (C), and
vertebrae (D).
they will improve the safety of the procedure and the
quality (accuracy and reproducibility) of the metabolic data.
Both the incidence of cardiac complications and
the verification of placement can only be assessed by
thoracotomy; therefore, we studied these issues in
patients undergoing thoracotomy for coronary artery
bypass graft surgery (CABG). Our findings indicate
that small cardiac complications may be more common than believed, and that placement accuracy can
be achieved by using the suggested criteria.
Materials and Methods
The study was performed as a part of a metabolic study for
which written informed consent of the patients and approval by
the local Human Investigation Committee were obtained. Sixtytwo patients with two-vessel or three-vessel coronary artery
disease documented by coronary arteriography (New York Heart
Association class III-IV), scheduled for CABG with the use of
extracorporeal circulation (ECC), were included. All patients had
a left ventricular ejection fraction ⬎ 50%. Cardiac medications,
including ␤-blockers, calcium entry blockers, nitrates, and antihypertensive agents, were continued and administered on the
morning of the operation. The patients were premedicated with
0.03 to 0.06 mg/kg lorazepam 30 min prior to transportation to
the operating theater.
After induction of anesthesia with midazolam (60 to 80 ␮g/kg),
sufentanil (1 to 1.5 ␮g/kg), etomidate (0.2 to 0.3 mg/kg), and
pancuronium bromide (0.1 mg/kg),13 two 7F Arrow introducers
(AK-09701-A; Arrow International; Reading, PA) were inserted
in the right internal jugular vein, punctured at the level of the
cricoid just lateral of the right carotid artery. A pulmonary artery
catheter (Baxter; Irvin, CA) was inserted through the first
introducer. The bend of this catheter through the heart, visualized by radiograph examination, was used as a marker to position
the CS catheter. The CS catheter (Baim CS Flow Thermal
Dilution Catheter; Elecath; Rahway, NJ) was inserted through
the second introducer, positioned cephalad of the first introducer, under continuous pressure measurement at the distal tip,
and with interval radiographic examination. Using anteroposterior fluoroscopy (Fig 1), the CS catheter was manipulated so that
its position was horizontal and slightly cranial from the position of
the pulmonary artery catheter, with the tip pointing toward the
left shoulder. Simultaneously, distal tip pressures were recorded.
If the distal tip pressure of the CS catheter increased ⬎ 10 mm
Hg above central venous pressure (CVP), and no ventricular
pressure curve could be distinguished, the catheter was assumed
to have impacted on the trabecular ventricular wall and the
catheter was drawn back into the superior vena cava. Increased
resistance to insertion of the CS catheter, and distal tip pressures
2 to 3 mm Hg greater than CVP indicated positioning in the CS
ostium. Fluoroscopy was then again performed, and the tip was
positioned approximately 4 cm into the CS lumen. Administration of contrast medium via the distal and proximal opening of
the CS catheter visualized the CS as a tube, with a retrograde
bloodstream disappearing along the catheter into the right atrium
(Fig 2).
CS oxygen saturation and CS flow were measured. Ganz et al3
developed a retrograde thermodilution technique for the measurement of CS, which can be used in humans.4,14 A catheter with
a temperature-sensitive thermistor is positioned in the CS. CS
flow measurements were performed with a continuous infusion
of NaCl (0.9%) at room temperature for a period of 30 s with a
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Clinical Investigations
Table 1—Blood Sampling in Patients Undergoing
CABG
Table 3—Placement of CS Catheter in Patients
Undergoing CABG
Times
Periods
Variables
T1
T2
T3
T4
T5
T6
T7
Before incision
After incision
20 min after X-off
50 min after X-off
2 h after X-off (at the ICU)
4 h after X-off
6 h after X-off
Placement
Successful
Unsuccessful
During operation
Good catheter position
Dislocation
After operation
Good catheter position
Dislocation
constant flow rate of injection (Finj) of 50 mL/min (Mark V
infusion pump; Metrad) through the distal lumen of the CS
catheter. The saline solution mixes with the blood (which has a
higher and known temperature).
The temperature of the saline solution and blood mixture (Tm)
depends on blood flow, infusion rate, blood temperature (Tb),
the temperature of the infused saline solution (Ti), the Finj, and
a constant value (C). This results in the following formula: CS
flow ⫽ (Tm ⫺ Ti/Tb ⫺ Tm) ⫻ Finj ⫻ C (Fig 2).
The use of the CS catheter for blood sampling and flow
measurements has several limitations. The CS is a venous sinus
collecting blood from many tributaries. This implies that the
position of the catheter tip determines the part of the heart that
is represented in the measurements. Consequently, a shift in
catheter position causes a change in measured flow. The catheter
position will therefore hamper the comparison of flow measurements between patients because it is impossible to achieve
identical catheter positions in different patients; however, if
catheter position remains stable, proportional changes of the flow
over time within one patient can be measured accurately.
Another source of error consists of the influx of atrial blood into
the CS.15 Influx of atrial blood during the measurement dilutes
the saline solution that is infused and causes an overestimation
of the CS flow. To prevent such flow measurement errors, the
tip of the CS catheter has to be inserted 4 cm into the CS. Data
were analyzed with a CS flow analyzer (Baim model 7 L-C2000;
Elecath) and Baim CS flow calculator (Elecath).
After thoracotomy, the cardiac surgeon inspected the heart and
palpated the CS region and, when possible, inspected the CS.
Placement was regarded as successful when fluoroscopy indicated the catheter was in the CS, when the mean CS oxygen
saturations were in the range of 40 to 60%, when CS flow was
approximately 2 to 3% of the measured cardiac output, and when
the distal pressure was slightly greater than CVP. The catheter
was considered to be dislocated, during operation and postoperatively, if CS oxygen saturation was similar to mixed venous
oxygen saturation, if CS flow could not be measured, or if distal
tip pressure was the same as CVP or showed a ventricular
pressure curve. Samples were obtained and measurements performed before incision, after incision, 20 min and 50 min after
aortic cross-clamp release (X-off), and 2 h, 4 h, and 6 h after X-off
(Table 1).
57 (92)
5 (8)*
51 (89)
6 (11)†
48 (94)
3 (6)
*Including one placement in liver vein.
†Including one placement in venous canal.
ECC was performed at a flow of 2.4 L/m2 body surface area,
while maintaining a mean BP between 60 mm Hg and 80 mm
Hg. Patients were cooled to a Tb of 28 to 30°C. Statistical analysis
was performed by paired Student t test. Values were considered
to be significantly different at p ⬍ 0.05.
Results
The study group consisted of 62 subjects: 49 men
and 13 women. Patient demographics are outlined in
Table 2.
Catheter Placement
In 57 patients (92%), catheters were placed correctly; in 5 patients (8%), correct placement in the
CS could not be achieved (Table 3). In one patient,
early in the study, the catheter was inserted into a
liver vein that under fluoroscopy projected on the
same place as the CS. In another patient, placement
was impossible because the CS was angled too
sharply backwards and upwards. During the operation, dislocation occurred in six patients (11%). In
three patients (6%), the CS catheter dislocated
postoperatively. In 62 attempts of CS catheter placement, 48 attempts (77%) were successful and without any problems in the postoperative period. In all
patients with a dislocated catheter, CS oxygen saturations were similar to mixed venous oxygen saturations, and CS flow was not measurable. In two
patients, a ventricular pressure curve was observed
after CS dislocation.
Myocardial Complications
Table 2—CABG Patient Characteristics
Variables
Mean ⫾ SEM
Range
Grafts, No.
Age, yr
Aortic cross-clamp time, min
Perfusion time, min
3.8 ⫾ 0.2
62.4 ⫾ 1.3
38.7 ⫾ 2.2
59.8 ⫾ 2.5
1–6
36–77
13–89
38–110
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No. (%)
After thoracotomy and inspection of the myocardium, four patients (6%) showed blood in the pericardium (Table 4). Of these, three patients (5%)
showed small bleeding spots in the right ventricular
wall. Two patients (3%) showed contrast medium in
the right ventricular wall. During catheter placeCHEST / 124 / 4 / OCTOBER, 2003
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6.3 ⫾ 0.2
167 ⫾ 8
2.9 ⫾ 0.2
92.7 ⫾ 2.4
44.2 ⫾ 7.2
67.8 ⫾ 1.7
37.8 ⫾ 0.2
7.3 ⫾ 0.3
9.8 ⫾ 0.4
68,094 ⫾ 4,210
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*Data are presented as mean ⫾ SEM. Svo2 ⫽ mixed venous oxygen saturation. See Table 1 and Figure 3 legend for expansion of abbreviations.
5.8 ⫾ 0.2
157 ⫾ 9
2.9 ⫾ 0.2
87.2 ⫾ 2.3
50.4 ⫾ 6.9
72.7 ⫾ 1.5
36.5 ⫾ 0.4
7.1 ⫾ 0.5
9.4 ⫾ 0.4
74,703 ⫾ 4,541
5.1 ⫾ 0.2
141 ⫾ 8
2.9 ⫾ 0.2
76.1 ⫾ 1.5
50.9 ⫾ 5.1
75.7 ⫾ 1.5
35.7 ⫾ 0.3
5.7 ⫾ 0.3
9.2 ⫾ 0.6
82,340 ⫾ 5,180
6.0 ⫾ 0.2
163 ⫾ 8
2.8 ⫾ 0.2
77.2 ⫾ 1.9
49.6 ⫾ 8.1
76.2 ⫾ 3.1
35.7 ⫾ 0.3
9.6 ⫾ 0.5
11.2 ⫾ 0.4
67,038 ⫾ 3,826
T4
4.9 ⫾ 0.2
110 ⫾ 6
2.5 ⫾ 0.2
67.4 ⫾ 2.0
42.3 ⫾ 8.3
82.2 ⫾ 1.4
35.0 ⫾ 0.2
8.0 ⫾ 0.5
10.2 ⫾ 0.4
107,847 ⫾ 7,145
Placement of a CS catheter can cause minor
myocardial damage without evident clinical hemodynamic signs. Dhala et al8 reported the occurrence of
cardiac tamponade in three patients, and a pericardial effusion without hemodynamic consequences in
one patient during transcatheter ablation of posteroseptal accessory neural pathways.
In the setting of our study, CABG permitted
inspection of the heart and confirmation of the
correct placement of the CS catheter. In the absence
of thoracotomy, the reported complications would
have remained unnoticed. The CABG operation
allowed inspection of the heart and confirmation of
the correct placement of the CS catheter. The study
also demonstrated the reliability of CS flow, distal tip
pressure, CS saturation, and fluoroscopy as parameters for judging correct placement.
We chose not to use an approach via the groin, in
case it was needed for cannulation for ECC. We also
did not approach the CS via the subclavian veins, as
the extra curve in the subclavian veins can make
manipulation of the catheter more difficult. The
4.6 ⫾ 0.2
118 ⫾ 6
2.7 ⫾ 0.2
61.2 ⫾ 2.2
42.5 ⫾ 9.4
81.0 ⫾ 1.1
35.6 ⫾ 0.1
8.6 ⫾ 0.4
9.4 ⫾ 0.3
99,071 ⫾ 7,221
Discussion
T3
After X-off, cardiac output increased as compared
with preoperative values (Table 5). The variations in
cardiac output paralleled variations in CS flow (Fig
3). CS flow varied between 2% and 3% of cardiac
output (Table 5). The oxygen saturation of CS blood
varied between 30% and 60%, and was at every
sample point significantly different from mixed venous oxygen saturations. CS pressure was 1- to 2-mm
Hg greater than CVP. No hemodynamic changes
could be detected during catheter placement. CS
resistance was decreased after X-off, and CS flow
increased (Fig 4).
T2
CS Parameters
T1
ment, three patients (5%) showed an irregular heart
rhythm, all without hemodynamic consequences.
Variables
3 (4.8)
53 (85.4)
T5
T6
9 (14.5)
4 (6.4)
3 (4.8)
2 (3.2)
Table 5—Perioperative Hemodynamic Measurements in Patients Undergoing CABG*
Complications
Blood in pericardium
Ventricular hematoma
Contrast in right ventricular wall
(but successful placement)
Irregular heart rhythm
No complications
CO, L/min
CS flow, mL/min
CS flow/CO, %
Heart rate, beats/min
CS oxygen saturation, %
Svo2, %
CS temp, °C
CVP, mm Hg
CS pressure, mm Hg
CS resistance, dyne䡠s䡠cm⫺5
No. (%)
(n ⫽ 62)
Variables
6.2 ⫾ 0.2
153 ⫾ 7
2.6 ⫾ 0.1
69.6 ⫾ 1.6
52.6 ⫾ 9.0
79.9 ⫾ 1.5
36.2 ⫾ 0.3
9.2 ⫾ 0.4
10.6 ⫾ 0.6
61,371 ⫾ 2,745
T7
Table 4 —Complications After CS Catheter Placement
in Patients Undergoing CABG
Clinical Investigations
Figure 2. Schematic drawing of the CS and CS catheter.
cranial approach via the right jugular vein is more
direct, and in most patients there is sufficient space
for the introduction of two 7F introducers.
or correct position; however, elevated pressures
helped to find the right position during insertion.
Fluoroscopy
Pressure Measurement
CS catheter distal tip pressure measurements
could not prevent the occurrence of right ventricular
hematoma in three patients. This happened in spite
of the fact that if even one of the four parameters
used to check the right position of the CS catheter
was out of range, we repeated the procedure to
correct the positioning. CS catheter placement in a
liver vein occurred in one patient early in the study.
CS pressure was only slightly greater than CVP and
therefore not an appropriate indicator for dislocation
Insertion of the CS catheter too deep in the CS or
great cardiac vein may cause artificially low measurements of CS flow; therefore, we performed fluoroscopy with contrast medium through the proximal
opening in the CS catheter at 4 cm of the tip.
Fluoroscopy visualized the CS. After injection of
contrast medium through the distal tip of the CS, the
contrast medium could be seen to disappear along
the catheter into the right atrium. Overinsertion also
became visible.
Prior placement of the pulmonary artery catheter
Figure 3. Perioperative CS flow and cardiac output in patients undergoing CABG. Values are
mean ⫾ SEM. CO ⫽ cardiac output; see Table 1 for definition of abbreviations.
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Figure 4. Perioperative CS flow and CS resistance index (res ind) in patients undergoing CABG.
Values are mean ⫾ SEM. See Table 1 for definition of abbreviations.
served as a useful landmark. The cranial curve of the
pulmonary artery catheter in the heart as shown by
fluoroscopy helped to locate the tricuspid valve and
the outlet of the CS into the right atrium. When the
CS catheter was inserted into the introducer, manipulated horizontally, cranially and parallel to the
pulmonary artery catheter, with the curve of the CS
catheter pointed in a posterior direction, and with
the tip pointing in the direction of the left shoulder,
the CS could be cannulated.
CS Flow
CS flow measurements should be in the range of 2
to 3% of cardiac output. If the CS catheter was
inserted ⬎ 4 to 5 cm into the CS, withdrawal of the
CS catheter induced an increase in flow that was at
a maximum when the catheter tip was introduced
approximately 4 cm in the CS.12 For this reason,
radiograph examination was also performed at the
postoperative ICUs to control the correct position
again. Bagger12 stated that due to differences in
catheter positioning, CS flows of different patients
should not be compared; therefore, we compared
within-patient values. We conclude that this ratio
may be another indication of correct placement.
Oxygen Saturation
Measuring CS oxygen saturation alone is not a
reliable parameter for determining catheter placement, because venous oxygen saturation in other
organs such as the liver, if they are in a low range,
may approach the upper levels of CS oxygen saturation. CS oxygen saturation is significantly lower than
the mixed venous oxygen saturation. When the CS
catheter is dislocated, the CS oxygen saturations
should equal the mixed venous oxygen saturation,
which was indeed the case in all patients in whom
dislocation occurred.
The use of a CS catheter is of great value in human
cardiac clinical research; however, insertion and use
of a CS catheter need careful attention. Fluoroscopy
and measurements of CS flow, CS oxygen saturation,
and distal tip pressure are necessary to control
correct placement, and proved to be adequate. Yet,
despite these precautions, minor myocardial damage
could not be prevented in approximately 10% of
patients. Importantly, these incidences went clinically unnoticed. This could be diminished by using
less-stiff catheters that are maneuverable with a wire
so that damage may be less.
Verifying the correct position of the CS catheter
increases the safety of using this device and improves
the reliability and quality of the obtained data. Most
complications occurred in the first 10 patients who
were studied. As time went on, our confidence in our
assessment of correct catheter position grew. As a
consequence, fewer episodes of catheter repositioning were necessary. Not unexpectedly, there appears
to be a learning curve for achieving correct positioning of a CS catheter.
References
1 Klocke F. Coronary blood flow in man. Prog Cardiovasc Dis
1976; 19:117–166
2 Sethna DH, Moffitt EA. An appreciation of the coronary
circulation. Anesth Analg 1986; 65:294 –305
3 Ganz W, Tamura K, Marcus H, et al. Measurement of
coronary sinus blood flow by continuous thermodilution in
man. Circulation 1971; 44:181–195
4 Baim D, Rothman M, Harrison D. Improved catheter for
regional coronary sinus flow and metabolic studies. Am J
Cardiol 1980; 46:997–1000
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Clinical Investigations
5 Specchia G, DeServi S, Poma E, et al. Clinical application of
monitoring techniques: coronary sinus blood flow monitoring.
Can J Cardiol 1986; Suppl A:170A–172A
6 Moffitt EA, Sethna DH. The coronary circulation and myocardial oxygenation in coronary artery disease: effects of
anesthesia. Anesth Analg 1986; 65:395– 410
7 Meisel E, Pfeiffer D, Engelmann L, et al. Investigation of
coronary venous anatomy by retrograde venography in patients with malignant ventricular tachycardia. Circulation
2001; 104:442– 447
8 Dhala AA, Deshpande SS, Bremner S, et al. Transcatheter
ablation of posteroseptal accessory pathways using a venous
approach and radiofrequency energy. Circulation 1994; 90:
1799 –1810
9 Iovino F, Pittiruti M, Buononato M, et al. Central venous
catheterization: complications of different placements. Ann
Chir 2001; 126:1001–1006
10 Defalque R, Nord HJ. Supraclavicular technique of subcla-
www.chestjournal.org
11
12
13
14
15
vian vein puncture for the anaesthesist. Anaesthesist 1970;
19:197–199
Figuerola M, Tomas MT, Armengol J, et al. Pericardial
tamponade and coronary sinus thrombosis associated with
central venous catheterization. Chest 1992; 101:1154 –1155
Bagger J. Coronary sinus blood flow determination by the
thermodilution technique: influence of catheter position and
respiration. Cardiovasc Res 1985; 19:27–31
Raza SMA, Masters RW, Zsigmond EK. Haemodynamic
stability with midazolam-sufentanil analgesia in cardiac surgical patients. Can J Anaesth 1988; 35:518 –525
Pepine C, Mehta J, Webster W, et al. In vivo validation of a
thermodilution method to determine regional left ventricular
blood flow in patients with coronary disease. Circulation
1978; 58:795– 802
Mathey D, Chatterjee K, Tyberg J, et al. Coronary sinus
reflux a source of error in the measurement of thermodilution
coronary sinus flow. Circulation 1978; 57:778 –786
CHEST / 124 / 4 / OCTOBER, 2003
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