Diagnosis of Ectopic Pregnancy

Correspondence Diagnosis of Ectopic Pregnancy K~rt Barnhart, MD Christos Coutifaris, MD, PhD

Diagnosis of Ectopic Pregnancy To the Editor."

Analgesia in Renal Colic Atan Jon Smally, MD Howard C M@nson, MD, ~omas R Caraccio, PharmD Don M Benson, DO

Reply William H Cordell, MD Allan B WoI~}on, MD Thomas J Maneatis, MD Lincoln Bynum, MD

Organophosphate Poisoning in Pregnancy Benoit Bailey, MD, MSc

Re_ply Tetsu Okumura, MD

Psychologic Treatment by EMS Personnel in Disasters Roy R Reeves, DO Harold B Pinhofsky, PhD, MD

Zolpidem and Hallucinations John 5 Marleowitz, PharmD Laura J Rames, MD Nikkt Reeves, MD Stephanie G Thomas, MD

Emergency Physicians and EMS Michael T McEvoy, PhD, REMT-P

Rhabdomyolysis And Suicidal Hydrocarbon [nhalation Alex P Betrosian Cristina A Palamarou Copyright © by the American College of Emergency Physicians.

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We would like to stress the importance of the findings of Kaplan et al in their recent article on the diagnosis of ectopic pregnancy in the emergency department [July 1996;28:10-17]. These authors noted the high incidence of ectopic pregnancy in a subgroup of women who presented to the ED with symptomatic pregnancy (pain, bleeding, or both) and a low I~-human chorionic gonadotropin (#-bCG)value. The importance of definitive diagnosis in this high-risk subgroup was appropriately emphasized by these investigators. Nevertheless, they state that no guidelines exist for diagnosis in the subgroup of patients with I}-hCG values below a cutoff bevel of 1,000 mlU/mL. Above this level a normal intrauterine pregnancy should be visualized; if not, ectopic pregnancy should be suspected. Kaplan et al mistakenly note that theirs is the first study to evaluate the diagnostic accuracy of every woman of reproductive age visiting an ED. In a much larger series published in 1994, which was not reviewed by Kaplan et al, we prospectively evaluated 1,588 consecutive

symptomatic first-trimester pregnancies and all ectopic pregnancies diagnosed over the course of 22 months in our ED.1 This number is nearly 20 times the sample size of the Kaplan study. In our report we stated many of the findings emphasized by Kaplan et al. With the use of our published algorithm we noted that a definitive diagnosis could be made at the time of ED presentation in 80% of women at risk for ectopic pregnancy. We also noted that 20% of the subjects in whom diagnosis could not be made on presentation had a higher relative risk for the eventual diagnosis of ectopic pregnancy. The percentage of women in this subgroup who were eventually found to have abnormal intrauterine pregnancies (62%), ectopic pregnancies (17%), and normal intrauterine pregnancies (11.5%) are very similar to the percentages reported by Kaplan et al. Our published algorithm for the diagnosis of an ectopic pregnancy (Figure) combines serum quantitative ~-hCG concentration, vaginal ultrasound findings, and extensive outpatient follow-up. This algorithm was 100% sensitive and 99.9% specific in the diagnosis of an ectopic pregnancy, Outpatient follow-up of this high-risk subgroup was demonstrated to be safe and eliminated the necessity and cost of

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CORRESPONDENCE

hospitalization in many of these women. In addition, outpatient serial #-hCG determinations helped us avoid the need for dilatation and curettage in many women with an original equivocal diagnosis, later confirmed to have the most common outcome of this subgroup, a completed abortion. We applaud Kaplan et al for drawing attention to the need for prompt diagnosis of ectopic pregnancy in the ED. However, we caution against the use of a costly diagnostic test such as ultrasound when the I~-hCG concentration is lower than that at which one would expect to visualize an intrauterine pregnancy. As noted by Kaplan et al, most ultrasound findings in this group are equivocal, and the sensitivity of ultrasound to detect ectopic pregnancy is only 36%. We also question the need for hospital admission of all subjects with equivocal diagnoses when a much larger prospective series has already demonstrated safe, efficient, prompt diagnosis with excellent sensitivity and specificity in an outpatient setting.

Kurt Bamhart, MD Christos Coutifaris, MD, PhD Department of Obstetrics and Gynecology Division of Human Reproduction University of Pennsylvania Medical Center Philadelphia, Pennsylvania

clinical practice is to administer up to 30 mg morphine in the first half hour. Because I believe we should provide pain relief if at all possible, I am eager to learn whether 60 mg IV ketorolac provides equally good pain relief with fewer side effects. I would also like to know whether giving the ketorolac and then beginning the titration of narcotic would alleviate the pain more rapidly or yield fewer side effects. In conclusion, I would like the authors to explain why the protocol was chosen and to comment on the informed consent obtained. It has been my experience that 50 mg IV meperidine almost never provides relief to a patient in significant pain from renal colic.

1. Barnhart K, Mennuti M, Benjamin I, et al: Prompt diagnosis of ectopic pregnancy in an emergency department setting. Obstet GynecoI1994-;84:1010~ 1015.

Analgesia in Renal Colic To the Editor. I offer the following comments on the clinical investigation by Cordell et al on pain relief in renal colic [August 1996;28:151-157]. Although I recognize the importance of funding in academic emergency medicine, I believe some drug studies do not lend themselves to sponsorship by drug companies. It is obvious that because only one (expensive) nonsteroidal agent is available for IV use, its maker stands to make a large profit if it can justify the drug's use. If indeed the study protocol is unassailably clinically relevant, someone should make a profit-it's the American way. If, however, the study protocol suggests to clinicians that an unfair comparison is made and the victor was preordained, the motivation for and the results of the study will be questioned. With regard to the selection and timing of doses for the medications given in this study, I believe we are comparing an apple and a bushel of oranges. I challenge any emergency physician in whom renal colic develops to agree to a maximum of 50 mg IV meperidine in the first half hour. When pain is significant, my

Alan Jon Smally, MD Department of EMS/Trauma Hartford Hospital University of Connecticut To the Editor, Cordell et al, in their article on the safety and efficacy of ketorolac, meperidine, and a combination of the two, failed to mention that the European Committee for Medical Proprietary Medical Products has restricted the use of ketorolac. 1 Approximately 80 fatalities associated with the use of ketorolac have been reported to this committee. Five countries-the Netherlands, Greece, Portugal, Germany,

Figure, Barnhart.

I I

I

<1,500 mlU/mL

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Outpatient follow-up

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Quantitative hCG I

>1,500 mlU/mL

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I

Ultrasound

I

I I

Normalincrease

]

>1,500mlU/mL

I I

Intrauterine pregnancy ]

I I Ultrasound I

I

Intrauterine pregnancy ]

I Serial hOG determination I I

I

I

I

Abnormal increase

I

I

[

I Surgicalmanagement

I

I No intrauterine pregnancy ]

]

I Surgical management

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]

I I

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I Surgical management ] The discriminatorylevel establishedat our institutionwas 1,500mlU/mL(third internationalreferencepreparationl.

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ANNALS OF EMERGENCYMEDICINE 29:2 FEBRUARY 1997