Should pregnancy testing be routine in adolescent patients prior to surgery?

Ruling out early trimester pregnancy when implementing community-based deworming programs

BACKGROUND

Large-scale deworming programs have, to date, mostly targeted preschool- and school-age children. As community-based deworming programs become more common, deworming will be offered to women of reproductive age. The World Health Organization recommends preventive chemotherapy be administered to pregnant women only after the first trimester. It is therefore important for deworming programs to be able to identify women in early pregnancy. Our objective was to validate a short questionnaire which could be used by deworming program managers to identify and screen out women in early pregnancy.

METHODOLOGY/PRINCIPAL FINDINGS

In May and June 2018, interviewers administered a questionnaire, followed by a pregnancy test, to 1,203 adult women living in the Peruvian Amazon. Regression analyses were performed to identify questions with high predictive properties (using the pregnancy test as the gold standard). Test parameters were computed at different decision tree nodes (where nodes represented questions). With 106 women confirmed to be pregnant, the positive predictive value of asking the single question 'Are you pregnant?' was 100%, at a 'cost' of a false negative rate of 1.9% (i.e. 21 women were incorrectly identified as not pregnant when they were truly pregnant). Additional questions reduced the false negative rate, but increased the false positive rate. Rates were dependent on both the combination and the order of questions.

CONCLUSIONS/SIGNIFICANCE

To identify women in early pregnancy when deworming programs are community-based, both the number and order of questions are important. The local context and cultural acceptability of different questions should inform this decision. When numbers are manageable and resources are available, pregnancy tests can be considered at different decision tree nodes to confirm pregnancy status. Trade-offs in terms of efficiency and misclassification rates will need to be considered to optimize deworming coverage in women of reproductive age.

Patient self assessment of pregnancy status in the emergency department

OBJECTIVES

Pregnancy tests are often performed routinely for female emergency department (ED) patients of reproductive age. One major reason is a perception that patients are unreliable in predicting their own pregnancy status. We hypothesised that patients could reliably predict that they were not pregnant.

METHODS

The study used a prospective cohort design, in an urban academic ED, from January 19 to May 19, 2004. All patients for whom a pregnancy test was ordered were asked about their sexual history as well as two additional questions: "Do you think you might be pregnant?" and "Is there any chance you could be pregnant?" Patients with already documented pregnancies were excluded.

RESULTS

A total of 474 patients had pregnancy tests performed that met inclusion criteria. Eleven (2.3%) tests were positive. Among patients who answered no to both questions (337), one test (0.3%) was positive (negative predictive value (NPV) 99.7%, likelihood ratio (LR) 0.13 (95% CI, 0.02 to 0.82)). The other historical factor with a high NPV (100%) was not being sexually active (LR not calculable). All pregnancies occurred in patients with gastrointestinal or genitourinary as the chief complaint: this comprised only 56% of the presentations for which tests were ordered.

CONCLUSION

Sexual history and self assessment can be used as a highly effective predictor of a patient not being pregnant. Given the risks of missed pregnancy in the ED, and low monetary and time cost of pregnancy tests, frequent testing is still recommended in most instances.

Laboratory tests in children undergoing ambulatory surgery: a review of clinical practice and scientific studies

The drive for cost containment in the United States has lead anesthesiologists to re-assess the benefits of routine pre-operative laboratory and radiological testing. The value of routine tests has been questioned not only by insurance companies but also by physicians. Common pre-operative laboratory and radiological tests are reviewed in the following analysis. Specifically, the use of such tests in children scheduled for ambulatory surgery is discussed. Current clinical practice patterns of pediatric anesthesiologists are included so that physicians may make conclusions on the basis of published literature and clinical practice of peers.