Evaluation of pediatric near-infrared cerebral oximeter for cardiac disease.

BACKGROUND: Cerebral hypoxia-ischemia remains a complication in children with congenital heart disease. Near-infrared spectroscopy can be utilized at the bedside to detect cerebral hypoxia-ischemia. This study aimed to calibrate and validate an advanced technology near-infrared cerebral oximeter for use in children with congenital heart disease. METHODS: After institutional review board approval and parental consent, 100 children less than 12 years and less than 40 kg were enrolled. Phase I (calibration) measured arterial and jugular venous saturation (SaO(2), SjO(2)) by co-oximetry simultaneously with device signals to calibrate an algorithm to determine regional cerebral saturation against a weighted average cerebral saturation (0.7 SjO(2) + 0.3 SaO(2)). Phase II (validation) evaluated regional cerebral saturation from the algorithm against the weighted average cerebral saturation by correlation, bias, precision, and A(Root Mean Square) assessed by linear regression and Bland-Altman analysis. RESULTS: Of 100 patients, 86 were evaluable consisting of 7 neonates, 44 infants, and 35 children of whom 55% were female, 79% Caucasian, and 41% with cyanotic disease. The SaO(2) and regional cerebral saturation ranged from 34% to 100% and 34% to 91%, respectively. There were no significant differences in subject characteristics between phases. For the entire cohort, A(RMS), bias, precision, and correlation coefficient were 5.4%, 0.5%, 5.39%, and 0.88, respectively. Age, skin color, and hematocrit did not affect these values. CONCLUSIONS: This cerebral oximeter accurately measures the absolute value of cerebral saturation in children over a wide range of oxygenation and subject characteristics, offering advantages in assessment of cerebral hypoxia-ischemia in congenital heart disease.

Intubation bougie dissection of tracheal mucosa and intratracheal airway obstruction.

Intubation bougies are commonly used to aid in intubation when an optimal view of the larynx is not obtained. We describe a case of tracheal perforation using a disposable intubation bougie resulting in a complete intratracheal airway obstruction relieved by cricothyrotomy. Disposable intubation bougies may have mechanical properties that differ from their nondisposable counterparts making complications more likely.

Classic intermittent claudication is an uncommon manifestation of lower extremity peripheral arterial disease in hospitalized patients with coronary artery disease.

Synchronous peripheral arterial disease (PAD) and coronary artery disease (CAD) is common. Standardized questionnaires such as the Rose/WHO questionnaire and later the Edinburgh modification of this questionnaire were developed to screen for PAD. Little data are available on the sensitivity of these questionnaires in hospitalized patients with CAD. The aim of this study was to determine the accuracy of these questionnaires and the prevalence of classic intermittent claudication in hospitalized patients with CAD. Medically stable patients with CAD were invited to participate before hospital discharge. The patients answered both the Rose/WHO and Edinburgh modification claudication questionnaires and had an ankle-brachial index (ABI) measured. An ABI less than or equal to 0.9 was considered to be indicative of significant PAD. Patients who had undergone previous lower extremity revascularization for PAD and had a corrected ABI greater than 0.9 were excluded. Ninety-five patients (66 men) were recruited. By measuring the ABI, 35 patients (25 men) were found to have significant PAD. An additional 3 patients who had an ABI corrected by lower extremity revascularization were excluded from the analysis. The Rose/WHO questionnaire had a sensitivity, specificity, and overall accuracy (95% CI) of 14.3% (2.7-25.9%), 96.7% (92.1-100%), and 66.3% (56.8-75.8%), respectively. The Edinburgh modification of the Rose/WHO questionnaire had a sensitivity, specificity, and overall accuracy (95% CI) of 28.6% (13.6-43.5%), 90.0% (82.4-97.6%), 67.4% (57.9-76.8%), respectively. Despite the high incidence of synchronous PAD in hospitalized patients with CAD, traditional claudication questionnaires are insensitive to PAD detection. Classic claudication is an uncommon manifestation of PAD in hospitalized patients with CAD.

Lower extremity peripheral arterial disease in hospitalized patients with coronary artery disease.

The prevalence of coronary artery disease (CAD) in patients with peripheral arterial disease (PAD) has been well defined. However, the prevalence of PAD in hospitalized patients with CAD has not been defined. The ankle-brachial index (ABI) is a useful non-invasive tool to screen for PAD. The aim of our study was to assess the prevalence of PAD in hospitalized patients with CAD by measuring the ABI. The study was conducted at the University of Wisconsin Hospital and Clinics inpatient Cardiovascular Medicine Service. Medically stable patients with CAD were invited to participate prior to hospital discharge. Data regarding cardiovascular risk factors, history of previous PAD, physical examination, and ABI were collected. An ABI less than or equal to 0.9 or a history of previous lower extremity vascular invention was considered to be indicative of significant PAD. A total of 100 patients (66 men and 34 women) were recruited. Forty patients were found to have PAD (mean ABI in non-revascularized patients with PAD = 0.67). By measuring the ABI, 37 (25 men) were positive for PAD and three had an ABI corrected with previous revascularization. Of these patients, 21 (52.5%) had previously documented PAD. Patients with PAD were older (p = 0.003), had a greater smoking history (p = 0.002), were more likely to have diabetes (p = 0.012), hypertension (p = 0.013) and a trend towards more dyslipidemia (p = 0.055). In conclusion, hospitalized patients with CAD are likely to have concomitant PAD. Risk factors for PAD in this patient population include advanced age, history of smoking, diabetes, hypertension, dyslipidemia and abnormal pulse examination. Identification of patients with PAD by measuring the ankle-brachial index is easily done.