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Thrombolyis for Acute Ischemic Stroke
Correspondence
Thrombolysis for Acute Ischemic Stroke
Joseph D'Addesio, MD
Thrombolyis for Acute Ischemic Stroke
Radiologists' Review of Radiographs
To the Editor:
Stephen W Smith, MD Dale Orton, MD Reply
Kirk Lufkin, MD Endotracheal Intubation by Basic EMTs
Evan P Weinstein, NREMT-P Reply
Michael R Sayre, MD Alan F Mistler, RN, EMT-P Janie L Evans, MSN, EMT-P Anthony T Kramer, RN, EMT-P Arthur M Pancio/i, MD Bolus Thrombolytic Infusions During CPR
Riyad B Abu-Laban, MD James Christenson, MD Grant Innes, MD lain MacPhail, MD
I was pleased that the November 1997 issue of Annals had at least 3 articles on the subject of thrombolysis for acute ischemic stroke. 1-3 Only the article by Wyer and Osborn 1 (the only authors who are emergency physicians, to my knowledge), came close to addressing the problems of initial diagnosis. As they so correctly state, "Clinical misidentification of patients as having ischemic stroke could lead to inappropriate administration of thrombolytic agents and obliterate the net benefits of the therapy." For those emergency physicians practicing in nonteaching hospitals, it may be difficult to be precise or certain in diagnosis, especially when no in-house neurologist exists who might verify subtle or questionable neurologic findings after a normal initial head computed tomographic (CT) scan. There are many conditions that can masquerade as stroke. Some of us practicing in nonteachiflg settings might have difficulty differentiating, for
example, a hemiplegic migraine from stroke, or a transient ischemic attack (TIA) that may clear several hours later from a potential candidate for recombinant tissue plasminogen activator (rt-PTA) therapy. There are also metabolic and functional causes of weakness, postictal states (such as Todd's paralysis). toxins, hypertension, and other conditions that might mimic stroke. In 1 excellent study that involved 411 patients, members of a stroke team misdiagnosed stroke nearly 20% of the time before the CT scan. 4 The article by Kasner and Grotta2 attempts to address similarities in decisionmaking with thrombolytic therapy in patients with myocardial infarction versus acute ischemic stroke. I believe, however, that there are more differences than similarities between these 2 types of patients. Having administered rt-PA to hundreds of patients with myocardial infarctions over the past decade, I can state with reasonable certainty that the key decisions in the care of the heart patient are much more concrete, and diagnostically easy. The patient must have chest pain, the ECG must be abnor-
R Douglas McKnight, MD
Joe Puskaric, EMT-P Richard Sadowski, EMT-P
Guidelines for Letters Annals welcomes correspondence, including observations, opinions, corrections, very brief reports, and comments on published articles. Letters to the editor will not be accepted if they exceed three double-spaced pages, with a maximum of 10 references. Two double-spaced copies must be submitted; a computer disk is appreciated but not required. They should not contain abbreviations Letters must be signed and include a postscript granting permiSSion to publish. Financial associations or other possible conflicts of interest should always be disclosed. Letters discussing an Annals article should be received within 6 weeks of the article's publication. Annals acknowledges receipt of letters with a postcard, and correspondents are notified by postcard when a decision is made. Published letters will be edited and may be shortened. Unpublished letters will not be returned. Neither Annals of Emergency Medicine nor the Publisher accepts responsibility for statements made by contributors or advertisers. Acceptance of an advertisment for placement in Annals in no way represents endorsement of a particular product or service by Annals of Emergency Medicine, the American College of Emergency Physicians, or the Publisher.
Martin Schecter, MD, PhD Catherina van Beek, RN Karen Wanger, MD Victor Wood, MD
SEPTEMBER 1998, PART 1
323
ANNALS OF EMERGENCY MEDICINE
389
CORRESPONDENCE
mal with easy to identify criteria, and the window of treatment is 6 hours or more. Contrast this with the potential ischemic stroke rt-PA patient. This latter patient requires an early normal CT scan. (The emergency physicians then asks himself or herself, "What if this is not a stroke?") In a nonteaching hospital, the emergency physician might fax a questionable ECG to the cardiologist on call for discussion. One cannot fax a patient's physical findings (which can change, and be physician dependent) to a neurologist taking call duty from home. I also question whether a neurologist on call can or will see such patients within the 3-hour treatment window. It is especially noteworthy to see that on the same page, the authors state that "the neurologist is not trained in rapid diagnosis and treatment." The tone of this statement and the article (as I see it) are that the critical decision of rt-PA or no rt-PA should be relinquished to the emergency physician, with all the inherent risks of administering such a powerful drug. Even "stroke team" initiatives are not the answer, if, in the final analysis, the emergency physician must make the treatment decisions all alone, with minimal bedside backup. Other authors have opened this topic for additional debate and healthy discussion. 5 Cap len et al report that the patients who respond best to intravenous rt-PA should be those patients with identified, precise lesions, located on the terminal branches of the middle cerebral artery. It is rightfully emphasized that although time is crucial in the initial assessment of ischemic stroke patients, so is the diagnosis. They recommend CT angiography or magnetic resonance angiography for precise localization. Perhaps, with such refinement, the 3-hour window could be extended longer. Indeed, accuracy and precision in diagnosis should be a requisite for thrombolytic drug administration. It is for the patient with a myocardial infarction. Shotgun administration of rt-PA for patients with possible ischemic stroke without a detailed diagnosis is wrong, potentially fatally wrong.
Joseph D'Addesio, MD Department of Emergency Medicine Houston Northwest Medical Center Houston, TX 1. Wyer PC, Osborn HH: Recombinant tissue plasminogen activator: In my community hospital ED, will early administration of rt-PA to patients with the initial diagnosis of
390
acute ischemic stroke reduce mortality and disability? Ann Emerg Med 1997;30:629-638. 2. Kasner SE. GrottaJe Emergency identification and treatment oj acute ischemic stroke. Ann Emerg Med 1997;30:642-653. 3. Haley EC Jr, Lewandowski C, Tilley BC. et ale Myths regarding the NINDS rt-PA Stroke Trial: Setting the record straight. Ann Emerg Med 1997;30:676-682. 4. Libman R, Wirkowski E, AIvir J, et ale Conditions that mimic stroke in the emergency department. Arch Neurol 1995;52:1119-1122.
5. Caplen LR, Mohr JP, Koroshets W: Trombolysis-Not a panacea Jar ischemic stroke. N Engl] Med 1997;337:13091310.
Radiologists' Review of Radiographs To the Editor: A mistake in the article, "Radiologists' Review of Radiographs Interpreted Confidently by Emergency Physicians Infrequently Leads to Changes in Patient Management'" has come to light. The sixth paragraph on p 203 should read as follows: "It is the practice at both EDs for physicians to record their radiographic interpretations, which are then provided with the radiographs to the radiologists for review. At the Level II EO, all radiologists' interpretations are transcribed and returned to the ED the following day; they are then reviewed by the ED physicians for discordances. All radiology interpretations are matched to the ED log to ensure that interpretations are provided for all radiographs. At the Levell EO, the radiologist
returns all discordant, but only discordant, readings to the EO for review. At both EOs, the ED physicians then make and document any management changes needed. These preexisting processes were not altered at either hospital during this study."
This difference in no way materially affects the study nor the results of the study. Stephen WSmith, MD Emergency Medicine Department Hennepin County Medical Center Minneapolis, MN 1. Lufkin KC. Smith SW, Mattick< CA. et ale Radiologists' review oj radiographs interpreted confidently by emergency physicians infrequently leads to changes in patient management. Ann Emerg Med 1998;31:202-207.
To the Editor: The article, "Radiologists' Review of Radiographs Interpreted Confidently by
Emergency Physicians Infrequently Leads to Change in Patient Management" in the February 1998 issue of Annals showed what emergency physicians already knew: next to the radiologist, when interpreting radiographs, we are the greatest. However, when is great not good enough? In our department, the average emergency physician interprets 3,000 films per year. The authors point out that 3 pulmonary nodules were missed by emergency physicians in the confident group. This translates to at least 1 missed cancer per year per physician, not including the "unconfidenf films. A recent article in the New England Journal ofMedicine showed that if a patient presents with chest pain, and an emergency physician has 2 sets of normal ECGs and cardiac enzymes with a certain time interval between, the chance of an untoward event-the patient dropping dead within 6 months-is about 2%.' Certainly a 2% false-negative rate for heart disease or less than a 1% false-negativeJate in the radiography study is laudable. However, in our department, the average emergency physician sees about 1,400 patients with chest pain each year. With a 2% miss rate, we would be sending home 30 patients per year for their "wrongful death" event. Rather than acost savings, a serious liability has occurred. The "mean between failure" time is an engineering term used to rate machinery. The mean between failure time for an ED clinician missing cancer or heart attack is zero. Until tort reform (eg, the English system) is enacted, if ever, don't widen the field of fire.
Dale Orton, MD Emergency Department Methodist-Children's Hospitals Omaha, NE 1. Hamm CW, Goldman BU. et al: Emergency room triage oj patients with acute chest pain by means of rapid testing for cardiac troponin T or troponin I. N Engl J Med 1997;337:1648-1653.
In reply: Thank you for the opportunity to respond to Dr Orton, He raises the ultimate question if the standard practice of radiologists' review of all ED radiographs is to be altered: How good is good enough? But how to define good? Radiologists' review of all radiographs is standard practice, congealed by convention. We
ANNALS OF EMERGENCY MEDICINE
323
SEPTEMBER 1998, PART 1
Thrombolysis for Acute Ischemic Stroke
Joseph D'Addesio, MD
Thrombolyis for Acute Ischemic Stroke
Radiologists' Review of Radiographs
To the Editor:
Stephen W Smith, MD Dale Orton, MD Reply
Kirk Lufkin, MD Endotracheal Intubation by Basic EMTs
Evan P Weinstein, NREMT-P Reply
Michael R Sayre, MD Alan F Mistler, RN, EMT-P Janie L Evans, MSN, EMT-P Anthony T Kramer, RN, EMT-P Arthur M Pancio/i, MD Bolus Thrombolytic Infusions During CPR
Riyad B Abu-Laban, MD James Christenson, MD Grant Innes, MD lain MacPhail, MD
I was pleased that the November 1997 issue of Annals had at least 3 articles on the subject of thrombolysis for acute ischemic stroke. 1-3 Only the article by Wyer and Osborn 1 (the only authors who are emergency physicians, to my knowledge), came close to addressing the problems of initial diagnosis. As they so correctly state, "Clinical misidentification of patients as having ischemic stroke could lead to inappropriate administration of thrombolytic agents and obliterate the net benefits of the therapy." For those emergency physicians practicing in nonteaching hospitals, it may be difficult to be precise or certain in diagnosis, especially when no in-house neurologist exists who might verify subtle or questionable neurologic findings after a normal initial head computed tomographic (CT) scan. There are many conditions that can masquerade as stroke. Some of us practicing in nonteachiflg settings might have difficulty differentiating, for
example, a hemiplegic migraine from stroke, or a transient ischemic attack (TIA) that may clear several hours later from a potential candidate for recombinant tissue plasminogen activator (rt-PTA) therapy. There are also metabolic and functional causes of weakness, postictal states (such as Todd's paralysis). toxins, hypertension, and other conditions that might mimic stroke. In 1 excellent study that involved 411 patients, members of a stroke team misdiagnosed stroke nearly 20% of the time before the CT scan. 4 The article by Kasner and Grotta2 attempts to address similarities in decisionmaking with thrombolytic therapy in patients with myocardial infarction versus acute ischemic stroke. I believe, however, that there are more differences than similarities between these 2 types of patients. Having administered rt-PA to hundreds of patients with myocardial infarctions over the past decade, I can state with reasonable certainty that the key decisions in the care of the heart patient are much more concrete, and diagnostically easy. The patient must have chest pain, the ECG must be abnor-
R Douglas McKnight, MD
Joe Puskaric, EMT-P Richard Sadowski, EMT-P
Guidelines for Letters Annals welcomes correspondence, including observations, opinions, corrections, very brief reports, and comments on published articles. Letters to the editor will not be accepted if they exceed three double-spaced pages, with a maximum of 10 references. Two double-spaced copies must be submitted; a computer disk is appreciated but not required. They should not contain abbreviations Letters must be signed and include a postscript granting permiSSion to publish. Financial associations or other possible conflicts of interest should always be disclosed. Letters discussing an Annals article should be received within 6 weeks of the article's publication. Annals acknowledges receipt of letters with a postcard, and correspondents are notified by postcard when a decision is made. Published letters will be edited and may be shortened. Unpublished letters will not be returned. Neither Annals of Emergency Medicine nor the Publisher accepts responsibility for statements made by contributors or advertisers. Acceptance of an advertisment for placement in Annals in no way represents endorsement of a particular product or service by Annals of Emergency Medicine, the American College of Emergency Physicians, or the Publisher.
Martin Schecter, MD, PhD Catherina van Beek, RN Karen Wanger, MD Victor Wood, MD
SEPTEMBER 1998, PART 1
323
ANNALS OF EMERGENCY MEDICINE
389
CORRESPONDENCE
mal with easy to identify criteria, and the window of treatment is 6 hours or more. Contrast this with the potential ischemic stroke rt-PA patient. This latter patient requires an early normal CT scan. (The emergency physicians then asks himself or herself, "What if this is not a stroke?") In a nonteaching hospital, the emergency physician might fax a questionable ECG to the cardiologist on call for discussion. One cannot fax a patient's physical findings (which can change, and be physician dependent) to a neurologist taking call duty from home. I also question whether a neurologist on call can or will see such patients within the 3-hour treatment window. It is especially noteworthy to see that on the same page, the authors state that "the neurologist is not trained in rapid diagnosis and treatment." The tone of this statement and the article (as I see it) are that the critical decision of rt-PA or no rt-PA should be relinquished to the emergency physician, with all the inherent risks of administering such a powerful drug. Even "stroke team" initiatives are not the answer, if, in the final analysis, the emergency physician must make the treatment decisions all alone, with minimal bedside backup. Other authors have opened this topic for additional debate and healthy discussion. 5 Cap len et al report that the patients who respond best to intravenous rt-PA should be those patients with identified, precise lesions, located on the terminal branches of the middle cerebral artery. It is rightfully emphasized that although time is crucial in the initial assessment of ischemic stroke patients, so is the diagnosis. They recommend CT angiography or magnetic resonance angiography for precise localization. Perhaps, with such refinement, the 3-hour window could be extended longer. Indeed, accuracy and precision in diagnosis should be a requisite for thrombolytic drug administration. It is for the patient with a myocardial infarction. Shotgun administration of rt-PA for patients with possible ischemic stroke without a detailed diagnosis is wrong, potentially fatally wrong.
Joseph D'Addesio, MD Department of Emergency Medicine Houston Northwest Medical Center Houston, TX 1. Wyer PC, Osborn HH: Recombinant tissue plasminogen activator: In my community hospital ED, will early administration of rt-PA to patients with the initial diagnosis of
390
acute ischemic stroke reduce mortality and disability? Ann Emerg Med 1997;30:629-638. 2. Kasner SE. GrottaJe Emergency identification and treatment oj acute ischemic stroke. Ann Emerg Med 1997;30:642-653. 3. Haley EC Jr, Lewandowski C, Tilley BC. et ale Myths regarding the NINDS rt-PA Stroke Trial: Setting the record straight. Ann Emerg Med 1997;30:676-682. 4. Libman R, Wirkowski E, AIvir J, et ale Conditions that mimic stroke in the emergency department. Arch Neurol 1995;52:1119-1122.
5. Caplen LR, Mohr JP, Koroshets W: Trombolysis-Not a panacea Jar ischemic stroke. N Engl] Med 1997;337:13091310.
Radiologists' Review of Radiographs To the Editor: A mistake in the article, "Radiologists' Review of Radiographs Interpreted Confidently by Emergency Physicians Infrequently Leads to Changes in Patient Management'" has come to light. The sixth paragraph on p 203 should read as follows: "It is the practice at both EDs for physicians to record their radiographic interpretations, which are then provided with the radiographs to the radiologists for review. At the Level II EO, all radiologists' interpretations are transcribed and returned to the ED the following day; they are then reviewed by the ED physicians for discordances. All radiology interpretations are matched to the ED log to ensure that interpretations are provided for all radiographs. At the Levell EO, the radiologist
returns all discordant, but only discordant, readings to the EO for review. At both EOs, the ED physicians then make and document any management changes needed. These preexisting processes were not altered at either hospital during this study."
This difference in no way materially affects the study nor the results of the study. Stephen WSmith, MD Emergency Medicine Department Hennepin County Medical Center Minneapolis, MN 1. Lufkin KC. Smith SW, Mattick< CA. et ale Radiologists' review oj radiographs interpreted confidently by emergency physicians infrequently leads to changes in patient management. Ann Emerg Med 1998;31:202-207.
To the Editor: The article, "Radiologists' Review of Radiographs Interpreted Confidently by
Emergency Physicians Infrequently Leads to Change in Patient Management" in the February 1998 issue of Annals showed what emergency physicians already knew: next to the radiologist, when interpreting radiographs, we are the greatest. However, when is great not good enough? In our department, the average emergency physician interprets 3,000 films per year. The authors point out that 3 pulmonary nodules were missed by emergency physicians in the confident group. This translates to at least 1 missed cancer per year per physician, not including the "unconfidenf films. A recent article in the New England Journal ofMedicine showed that if a patient presents with chest pain, and an emergency physician has 2 sets of normal ECGs and cardiac enzymes with a certain time interval between, the chance of an untoward event-the patient dropping dead within 6 months-is about 2%.' Certainly a 2% false-negative rate for heart disease or less than a 1% false-negativeJate in the radiography study is laudable. However, in our department, the average emergency physician sees about 1,400 patients with chest pain each year. With a 2% miss rate, we would be sending home 30 patients per year for their "wrongful death" event. Rather than acost savings, a serious liability has occurred. The "mean between failure" time is an engineering term used to rate machinery. The mean between failure time for an ED clinician missing cancer or heart attack is zero. Until tort reform (eg, the English system) is enacted, if ever, don't widen the field of fire.
Dale Orton, MD Emergency Department Methodist-Children's Hospitals Omaha, NE 1. Hamm CW, Goldman BU. et al: Emergency room triage oj patients with acute chest pain by means of rapid testing for cardiac troponin T or troponin I. N Engl J Med 1997;337:1648-1653.
In reply: Thank you for the opportunity to respond to Dr Orton, He raises the ultimate question if the standard practice of radiologists' review of all ED radiographs is to be altered: How good is good enough? But how to define good? Radiologists' review of all radiographs is standard practice, congealed by convention. We
ANNALS OF EMERGENCY MEDICINE
323
SEPTEMBER 1998, PART 1