The development and validation of a risk score to predict the probability of postoperative vomiting in pediatric patients.

Risk scores to predict the occurrence of postoperative vomiting (PV) or nausea and vomiting that were developed for adult patients do not fit for children, because several risk factors are difficult to assess or are usually not applicable in pediatric patients (e.g., smoking status). Thus, in the present study, we sought to develop and to validate a simple score to predict PV in children (POVOC-score). Development and validation of the new score was based on data from 4 independent institutions of 1257 children (aged 0-14 yr) undergoing various types of surgery under general anesthesia without antiemetic prophylaxis. Preoperatively, several potential risk factors were recorded. Postoperatively, the occurrence of PV was observed for up to 24 h. The dataset was randomly split into an evaluation set (n = 657) that was analyzed using a forward logistic regression technique and a validation set (n = 600) that was used to confirm the accuracy of prediction by means of the area under a receiver operating characteristic curve. Four independent risk factors for PV were identified in the final analysis: duration of surgery >/=30 min, age >/=3 yr, strabismus surgery, and a positive history of PV in the children or PV/postoperative nausea and vomiting in relatives (mother, father, or siblings). The incidence of PV was 9%, 10%, 30%, 55%, and 70% for 0, 1, 2, 3, and 4 risk factors observed. Using these incidences as cut-off values in the validation dataset, the area under the receiver operating characteristic curve was 0.72 (95% confidence interval: 0.68-0.77). Our data suggest that PV can be predicted with an acceptable accuracy using a four-item simplified risk score.

Applicability of risk scores for postoperative nausea and vomiting in adults to paediatric patients.

BACKGROUND: Scores to predict the occurrence of postoperative vomiting (PV) or nausea and vomiting (PONV) are well established in adult patients. The aim of this survey was to evaluate the applicability of risk scores developed and tested in adult patients in 983 paediatric patients (0-12 yr) undergoing various surgical procedures. METHOD: The predictive properties of five models were compared with respect to discriminating power (measured by the area under a receiver operating characteristic curve) and calibration (comparison of the predicted and the actual incidences of the disease by weighed linear regression analysis). RESULTS: The cumulative incidence of PV was 33.2% within 24 h. The discriminating power was low and insufficient in all models tested (0.56-0.65). Furthermore, the predicted incidences of the scores correlated only vaguely with the actual incidences observed. CONCLUSION: Specialized scores for children are required. These might use the history of PV, strabismus surgery, duration of anaesthesia > or =45 min, age > or =5 yr and administration of postoperative opioids as independent risk factors.

Noninvasive diagnosis of coronary artery disease: a comparison between cardiokymographic and electrocardiographic stress testing.

Noninvasive cardiokymography has been further developed to be able to record wall motion abnormalities during exercise. The study was designed to evaluate the diagnostic accuracy of stress cardiokymography and electrocardiography in the diagnosis of coronary artery disease. 223 patients were included in a prospective investigation using a newly developed computerized cardiokymography device. Sensitivity, specificity, and positive predictive value were 61, 69 and 90% for exercise cardiokymography, and 57, 74 and 91% for exercise electrocardiography, respectively. There was no statistically significant difference between cardiokymography and electrocardiography. The combination of electrocardiography and cardiokymography did not produce a significant improvement in diagnostic accuracy in comparison to exercise electrocardiography alone.

Electrocardiographic exercise stress testing for cardiac risk assessment in patients undergoing noncardiac surgery.

BACKGROUND: The value of exercise electrocardiography in the prediction of perioperative cardiac risk has yet to be defined. This study was performed to determine the predictive value of exercise electrocardiography as compared with clinical parameters and resting electrocardiography. METHODS: A total of 204 patients at intermediate risk for cardiac complications prospectively underwent exercise electrocardiography before noncardiac surgery. Of these, 185 were included in the final evaluation. All patients underwent follow-up evaluation postoperatively by Holter monitoring for 2 days, daily 12-lead electrocardiogram, and creatine kinase, creatine kinase MB, and troponin-T measurements for 5 days. Cardiac events were defined as cardiac death, myocardial infarction, minor myocardial cell injury, unstable angina pectoris, congestive heart failure, and ventricular tachyarrhythmia. Potential risk factors for an adverse event were identified by univariate and multivariate logistic regression analysis. RESULTS: Perioperative cardiac events were observed in 16 patients. There were 6 cases of myocardial infarction and 10 cases of myocardial cell injury. The multivariate correlates of adverse cardiac events were definite coronary artery disease (odds ratio, 8.8; 95% confidence interval [CI], 1.1--73.1; P = 0.04), major surgery (odds ratio, 4.7; 95% CI, 1.3--16.3; P = 0.02), reduced left ventricular performance (odds ratio, 2.0; 95% CI, 1.1--3.8; P = 0.03), and ST-segment depression of 0.1 mV or more in the exercise electrocardiogram (odds ratio, 5.2; 95% CI, 1.5--18.5; P = 0.01). A combination of clinical variables and exercise electrocardiography improved preoperative risk stratification. CONCLUSIONS: This prospective study shows that a ST-segment depression of 0.1 mV or more in the exercise electrocardiogram is an independent predictor of perioperative cardiac complications.

Effects of hypothyroidism on bronchial reactivity in non-asthmatic subjects.

The effect of hypothyroidism on non-specific bronchial reactivity was studied in 11 patients without pulmonary disease (mean age 40 (SD 13) years) who had had a total thyroidectomy and radioiodine treatment for thyroid cancer 41 (36) months before the study. All patients when mildly hyperthyroid while having long term thyroxine replacement treatment and once when hypothyroid two weeks after stopping triiodothyronine for the purpose of screening for metastases. Bronchial reactivity was assessed by measuring specific airways conductance (sGaw) after increasing doses of inhaled carbachol (45-1260 micrograms). The dose producing a 35% decrease in sGaw (PD35) was determined from the cumulative log dose-response curve by linear regression analysis. Mean baseline sGaw values were similar when the patients were hypothyroid and when they were hyperthyroid (1.35 (0.36) and 1.41 (0.56) s-1 kPa-1). The interstudy coefficients of variation of baseline sGaw were higher in the thyroid patients than in a euthyroid control group (14% versus 8%). Geometric mean PD35 was lower when the patients were hypothyroid (97 micrograms) than when they were mildly hyperthyroid (192 micrograms). It is concluded that acute hypothyroidism increases non-specific bronchial reactivity in nonasthmatic subjects.