Anesth Analg 2004;98:614-616
© 2004 International Anesthesia Research Society
doi: 10.1213/01.ANE.0000100393.69174.12
CARDIOVASCULAR ANESTHESIA
Damage to Pulmonary Artery Catheter During Transmyocardial Laser Revascularization
Bharathi H. Scott, MD,
Anthony J. Ippolito, MD, and
Irvin B. Krukenkamp, MD
From the Departments of Anesthesiology and Surgery, State University of New York at Stony Brook, Stony Brook, New York
Address correspondence and reprint requests to Bharathi H. Scott MD, Department of Anesthesiology, SUNY at Stony Brook, Health Sciences Center, L4–060, Stony Brook, NY 11794–8480. Address email to bscott{at}anesthes.sunysb.edu
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Abstract
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This case report describes damage to a pulmonary artery catheter (PAC) during transmyocardial laser revascularization. We observed persistent bleeding and a temperature reading of "too high" from the temperature connection port of PAC during cardiopulmonary bypass while the patient’s nasopharyngeal temperature read 34°C. This alerted us to the possibility of PAC damage during creation of laser channels in the right coronary artery territory on the inferior surface of the heart. This is a unique complication related to this coronary revascularization procedure.
IMPLICATIONS: We report an unusual case of pulmonary artery catheter (PAC) damage during transmyocardial laser revascularization (TMLR). This observation should alert the anesthesiologist to the fact that the PAC may be damaged when TMLR is performed on the right side of the heart. We recommend that the PAC be withdrawn during this procedure.
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Introduction
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Transmyocardial laser revascularization (TMLR) is a therapeutic option for patients suffering from ischemic heart disease and refractory angina pectoris not amenable to conventional medical and surgical modalities. In this procedure, a high-energy laser is used to create transmural channels through oxygen-deprived heart muscle to improve myocardial per-fusion. The mechanism of action is thought to be an-giogenesis and sympathetic denervation (1,2). A pulmonary artery catheter (PAC) is frequently used for monitoring cardiac surgical procedures. Potential complications associated with this device have become well delineated (3,4). With the introduction of new surgical techniques, potential complications become apparent with increasing use. We report damage to a PAC associated with TMLR, a complication not previously reported in the literature for this surgical procedure.
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Case Report
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A 60-yr-old man presented for coronary artery bypass graft surgery (CABG) with TMLR. His medical history was significant for diabetes mellitus and hypertension. Cardiac catheterization showed triple vessel coronary artery disease, moderate ventricular dysfunction, and ejection fraction of 35%. The right coronary artery was diminutive and non-bypassable. CABG and TMLR of the right coronary territory were planned. Intraoperative monitoring included standard American Society of Anesthesiologists and our standard monitors for patients undergoing coronary artery surgery. This included 5-lead electrocardiograms (ECG) with continuous automated ST segment analysis, a radial artery catheter for continuous arterial pressure determination, and a thermodilution paceport PAC (Model 931HF75; Edwards Lifesciences Corp, Irvine, CA). A transesophageal echocardiography probe was inserted to monitor and confirm the successful laser penetration of the myocardium. General anesthesia was induced using a combination of fentanyl 5–10 µg/kg and midazolam 0.05–0.1 mg/kg; vecuronium 0.1 mg/kg was used for neuromuscular blockade. Anesthesia was maintained with isoflurane, supplemented with propofol as indicated. Before initiating cardiopulmonary bypass (CPB) TMLR was performed on the inferior surface of the heart on the right side using CO2 heart laser (The Heart Laser System; PLC Medical Systems, Inc., Franklin, MA). During this procedure the surgeon places a laser on the epicardial surface of the target area and applies sufficient energy to create small channels from the epicardial to the endocardial surfaces. A successful laser penetration is evidenced by a burst of bubbles on the echocardiogram created by the contact of the laser beam with the blood leading to photo molecular destruction of red blood cells. Forty joules energy with 50-ms pulse duration was used. Ten laser channels were successfully created in the right coronary artery distribution. The TMLR was performed without incident. After completion of TMLR, CPB was initiated. During CPB it was noticed that the temperature from the PAC was reading blood temperature "too high" and blood was oozing from the hub of the temperature connection port of the PAC. We noted a nasopharyngeal temperature of only 34°C at this time. At first, the PAC was pulled back 2–4 cm to see if the temperature reading would change, but it continued to read "too high." It was decided that the position of the PAC would be checked and confirmed during the weaning process when the heart is filled with blood. The patient was weaned from CPB and the vital signs were stable. At this time we were not able to achieve satisfactory PAC waveforms and the blood temperature was still reading "too high." We suspected a serious malfunction of the PAC related to use of laser and removed the catheter without any difficulty. On examination the PAC was noticed to have been partially transected (Figs. 1 and 2 ). The remainder of the surgery and postoperative course were uneventful and the patient was discharged on the fifth postoperative day.
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Discussion
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TMLR is a relatively new surgical technique. During this procedure a high energy, computer synchronized laser beam is used to create transmural channels that improve vascularization to the ischemic myocardium (1,2). There are two types of laser systems in use, the CO2 and holmium-yttrium-aluminum-garnet (Ho:YAG) lasers. Both emit energy in the form of invisible infrared light. The CO2 laser emits energy as a continuous wave with minimal collateral damage. The Ho:YAG laser creates channels using multiple pulses and significant collateral damage. The CO2 laser has been shown to provide greater relief of angina. The CO2 laser is capable of delivering 800–850 watts of peak power to tissue. The maximum output is 80 joules, with most patients receiving 35–45 joules. The pulse width of the laser can be varied from 10 to 99 ms (5). TMLR is performed on a beating heart, and it is synchronized with the ECG to fire when the heart is maximally blood filled. This precise timing may reduce the risk of arrhythmia. The size of the ischemic area determines the number of channels attempted. Generally, the surgeon makes 1–2 laser channels per centimeter. TMLR is used in patients with severe ischemia, with previous bypasses, or with vessels that are too small to graft and thus not suitable for traditional bypass surgery (6). The purpose of TMLR is to relieve angina, increase myocardial perfusion, and improve the quality of life in patients not treatable by other medical or surgical modalities. The success of the TMLR is thought to be attributable to improved regional blood flow to the ischemic area. It is thought to stimulate angiogenesis and possibly produce sympathetic denervation leading to improvement in the symptoms of angina (7). TMLR is not without complications. The laser beam can inadvertently damage the myocardium, conduction system, mitral valve, and coronary vasculature. Energy from the CO2 can travel further and injure tissues distal to the intended perforation. In our patient we believe the laser beam inadvertently penetrated the PAC, which was traversing through the right ventricular cavity, and caused it to be partially transected at approximately 20 cm from the tip. This high-energy beam produced a break in the integrity of the catheter leading to thermistor damage and temperature reading of "too high." Normally when CPB is initiated there is a decrease of body temperature and cooling of the heart, leading to low temperature readings in the PAC temperature port. The unusual "high" temperature reading, dampened pressure wave forms, and oozing of blood from the connection site between the thermodilution cable and the PAC alerted us to the possibility of malfunction. It was fortunate that the entire PAC was easily removed without a portion of the catheter breaking and the distal portion dislodging in the heart, which would have required a return to CPB and opening of cardiac chambers to retrieve the transected segment. A transected segment of PAC could cause arrhythmias, damage to valves, or emboli, or become a source of sepsis.
We discussed this problem with the manufacturers of the PAC and TMLR systems and were informed that they were aware of one other case of PAC damage when TMLR of the septum was performed. They attributed this to the increased level of energy used. In our patient we used 40 joules of energy. Even though this is considered an adequate energy level for the left ventricle, it may have been excessive on the thinner right ventricle and when the heart was lifted to treat the inferior surface, the catheter may have been directly in contact with the endocardium in the line of the laser beam. Other reported complications related to PAC include catheter entrapment by sutures and thermistor damage, inadvertent cutting, fracture resulting from stress points, balloon rupture, thrombus formation, and catheter knotting (3,4). The unusual presentation in this report reminds us that constant vigilance is critical during cardiac surgical procedures near the PAC. To avoid this possible complication we suggest that during right-sided TMLR the PAC be withdrawn and re-advanced only after the TMLR is completed.
In summary we report a unique cause of damage to a PAC during TMLR of the right side of the heart.
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Acknowledgments
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We wish to acknowledge the assistance of Peter S. A. Glass, MBChB in preparation of this manuscript.
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References
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- Allen KB, Dowling RD, Fudge TL, et al. Comparison of transmyocardial revascularization with medical therapy in patients with refractory angina. N Engl J Med 1999; 341: 1029–36.[Abstract/Free Full Text]
- Frazier OH, March RJ, Horvath KA, et al. Transmyocardial revascularization with carbon dioxide laser in patients with end-stage coronary artery disease. N Engl J Med 1999; 341: 1021–8.[Abstract/Free Full Text]
- Kodavatiganti R, Hearn CJ, Insler SR. Bleeding from pulmonary artery catheter temperature connection. J Cardiothorac Vasc Anesth 1999; 13: 75–7.[ISI][Medline]
- Manecke GR, Brown JC, Landau AA, et al. An unusual case of pulmonary artery catheter malfunction. Anesth Analg 2002; 95: 302–4.[Abstract/Free Full Text]
- Landolfi CK, Landolfo KP, Hughes GC, et al. Intermediate-term clinical outcome following transmyocardial laser revascularization in patients with refractory angina pectoris. Circulation 1999; 100 (Suppl II): 128–33.
- Horvath KA, Aranki SF, Cohn LH, et al. Sustained angina relief 5 years after transmyocardial laser revascularization with a CO2 laser. Circulation 2001; 104: 181–4.[Abstract/Free Full Text]
- Domkowski PW, Biswas SS, Steenbergen C, et al. Histologic evidence of angiogenesis months after transmyocardial laser revascularization. Circulation 2001; 103: 469–71.[Free Full Text]
Accepted for publication September 17, 2003.
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Abstract
Introduction
