Evaluation of guidelines for ordering prothrombin and partial thromboplastin times

Thomas E. Auble, David McD Taylor, Edbert Hsu, Donald M. Yealy

Research output: Contribution to journalArticle

Abstract

Objectives: Existing clinical practice guidelines for ordering prothrombin time (PT) and partial thromboplastin time (PTT) tests in the emergency department (ED) include physician expectation of an invasive procedure as a criterion. This study sought to determine whether this criterion accurately identifies patients who undergo an invasive procedure and whether an amalgam of these guidelines identifies patients at low risk of an adverse medical outcome. Methods: A prospective observational cohort study of adults treated in a university medical center ED between July 1997 and March 1998. Physicians were surveyed at order placement to determine the presence of guideline criteria. Adverse clinical outcomes defined as an International Normalized Ratio [INR] > 1.3 or PTT > 39.9 seconds combined with consequent directed medical therapy were abstracted from ED and the first 24 hours of inpatient medical records. Results: The sensitivity of ED physician expectation of an invasive procedure was 60.0%; therefore, it was excluded from both the PT and PTT guidelines. There were 553 patients with a PT test order; test order indications were absent in 190 (34.4%), of which one (0.5%, 95% CI = 0.1% to 2.9%) had adverse outcomes. There were 547 patients with a PTT test; test order indications were absent in 226 (41.3%), of which three (1.3%, 95% CI = 0.4 to 3.8%) had adverse outcomes. All three were taking warfarin when they presented to the ED. Conclusions: Emergency department physician expectation of an invasive procedure for patients with PT or PTT test orders is an insensitive predictor of patients who undergo such procedures. Clinical practice guidelines that exclude this criterion identify ED patients at the time of ED presentation at low risk for adverse medical outcomes in the ED or shortly after admission.

Original languageEnglish (US)
Pages (from-to)567-574
Number of pages8
JournalAcademic Emergency Medicine
Volume9
Issue number6
DOIs
StatePublished - 2002
Externally publishedYes

Fingerprint

Partial Thromboplastin Time
Prothrombin
Hospital Emergency Service
Guidelines
Prothrombin Time
Physicians
Practice Guidelines
International Normalized Ratio
Warfarin
Medical Records
Observational Studies
Inpatients
Cohort Studies

Keywords

  • Bleeding
  • Emergency department
  • Guidelines
  • Partial thromboplastin time
  • Prothrombin time

ASJC Scopus subject areas

  • Emergency Medicine

Cite this

Evaluation of guidelines for ordering prothrombin and partial thromboplastin times. / Auble, Thomas E.; Taylor, David McD; Hsu, Edbert; Yealy, Donald M.

In: Academic Emergency Medicine, Vol. 9, No. 6, 2002, p. 567-574.

Research output: Contribution to journalArticle

Auble, Thomas E. ; Taylor, David McD ; Hsu, Edbert ; Yealy, Donald M. / Evaluation of guidelines for ordering prothrombin and partial thromboplastin times. In: Academic Emergency Medicine. 2002 ; Vol. 9, No. 6. pp. 567-574.
@article{33c5a8ee375343558534b19d6f78c270,
title = "Evaluation of guidelines for ordering prothrombin and partial thromboplastin times",
abstract = "Objectives: Existing clinical practice guidelines for ordering prothrombin time (PT) and partial thromboplastin time (PTT) tests in the emergency department (ED) include physician expectation of an invasive procedure as a criterion. This study sought to determine whether this criterion accurately identifies patients who undergo an invasive procedure and whether an amalgam of these guidelines identifies patients at low risk of an adverse medical outcome. Methods: A prospective observational cohort study of adults treated in a university medical center ED between July 1997 and March 1998. Physicians were surveyed at order placement to determine the presence of guideline criteria. Adverse clinical outcomes defined as an International Normalized Ratio [INR] > 1.3 or PTT > 39.9 seconds combined with consequent directed medical therapy were abstracted from ED and the first 24 hours of inpatient medical records. Results: The sensitivity of ED physician expectation of an invasive procedure was 60.0{\%}; therefore, it was excluded from both the PT and PTT guidelines. There were 553 patients with a PT test order; test order indications were absent in 190 (34.4{\%}), of which one (0.5{\%}, 95{\%} CI = 0.1{\%} to 2.9{\%}) had adverse outcomes. There were 547 patients with a PTT test; test order indications were absent in 226 (41.3{\%}), of which three (1.3{\%}, 95{\%} CI = 0.4 to 3.8{\%}) had adverse outcomes. All three were taking warfarin when they presented to the ED. Conclusions: Emergency department physician expectation of an invasive procedure for patients with PT or PTT test orders is an insensitive predictor of patients who undergo such procedures. Clinical practice guidelines that exclude this criterion identify ED patients at the time of ED presentation at low risk for adverse medical outcomes in the ED or shortly after admission.",
keywords = "Bleeding, Emergency department, Guidelines, Partial thromboplastin time, Prothrombin time",
author = "Auble, {Thomas E.} and Taylor, {David McD} and Edbert Hsu and Yealy, {Donald M.}",
year = "2002",
doi = "10.1197/aemj.9.6.567",
language = "English (US)",
volume = "9",
pages = "567--574",
journal = "Academic Emergency Medicine",
issn = "1069-6563",
publisher = "Wiley-Blackwell",
number = "6",

}

TY - JOUR

T1 - Evaluation of guidelines for ordering prothrombin and partial thromboplastin times

AU - Auble, Thomas E.

AU - Taylor, David McD

AU - Hsu, Edbert

AU - Yealy, Donald M.

PY - 2002

Y1 - 2002

N2 - Objectives: Existing clinical practice guidelines for ordering prothrombin time (PT) and partial thromboplastin time (PTT) tests in the emergency department (ED) include physician expectation of an invasive procedure as a criterion. This study sought to determine whether this criterion accurately identifies patients who undergo an invasive procedure and whether an amalgam of these guidelines identifies patients at low risk of an adverse medical outcome. Methods: A prospective observational cohort study of adults treated in a university medical center ED between July 1997 and March 1998. Physicians were surveyed at order placement to determine the presence of guideline criteria. Adverse clinical outcomes defined as an International Normalized Ratio [INR] > 1.3 or PTT > 39.9 seconds combined with consequent directed medical therapy were abstracted from ED and the first 24 hours of inpatient medical records. Results: The sensitivity of ED physician expectation of an invasive procedure was 60.0%; therefore, it was excluded from both the PT and PTT guidelines. There were 553 patients with a PT test order; test order indications were absent in 190 (34.4%), of which one (0.5%, 95% CI = 0.1% to 2.9%) had adverse outcomes. There were 547 patients with a PTT test; test order indications were absent in 226 (41.3%), of which three (1.3%, 95% CI = 0.4 to 3.8%) had adverse outcomes. All three were taking warfarin when they presented to the ED. Conclusions: Emergency department physician expectation of an invasive procedure for patients with PT or PTT test orders is an insensitive predictor of patients who undergo such procedures. Clinical practice guidelines that exclude this criterion identify ED patients at the time of ED presentation at low risk for adverse medical outcomes in the ED or shortly after admission.

AB - Objectives: Existing clinical practice guidelines for ordering prothrombin time (PT) and partial thromboplastin time (PTT) tests in the emergency department (ED) include physician expectation of an invasive procedure as a criterion. This study sought to determine whether this criterion accurately identifies patients who undergo an invasive procedure and whether an amalgam of these guidelines identifies patients at low risk of an adverse medical outcome. Methods: A prospective observational cohort study of adults treated in a university medical center ED between July 1997 and March 1998. Physicians were surveyed at order placement to determine the presence of guideline criteria. Adverse clinical outcomes defined as an International Normalized Ratio [INR] > 1.3 or PTT > 39.9 seconds combined with consequent directed medical therapy were abstracted from ED and the first 24 hours of inpatient medical records. Results: The sensitivity of ED physician expectation of an invasive procedure was 60.0%; therefore, it was excluded from both the PT and PTT guidelines. There were 553 patients with a PT test order; test order indications were absent in 190 (34.4%), of which one (0.5%, 95% CI = 0.1% to 2.9%) had adverse outcomes. There were 547 patients with a PTT test; test order indications were absent in 226 (41.3%), of which three (1.3%, 95% CI = 0.4 to 3.8%) had adverse outcomes. All three were taking warfarin when they presented to the ED. Conclusions: Emergency department physician expectation of an invasive procedure for patients with PT or PTT test orders is an insensitive predictor of patients who undergo such procedures. Clinical practice guidelines that exclude this criterion identify ED patients at the time of ED presentation at low risk for adverse medical outcomes in the ED or shortly after admission.

KW - Bleeding

KW - Emergency department

KW - Guidelines

KW - Partial thromboplastin time

KW - Prothrombin time

UR - http://www.scopus.com/inward/record.url?scp=0036271750&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0036271750&partnerID=8YFLogxK

U2 - 10.1197/aemj.9.6.567

DO - 10.1197/aemj.9.6.567

M3 - Article

C2 - 12045069

AN - SCOPUS:0036271750

VL - 9

SP - 567

EP - 574

JO - Academic Emergency Medicine

JF - Academic Emergency Medicine

SN - 1069-6563

IS - 6

ER -