Transhepatic catheterization using ultrasound-guided access.

The efficacy and safety of ultrasound guidance to obtain transhepatic access for cardiac catheterization were investigated in this study. The transhepatic route for access to perform cardiac catheterization has become an acceptable alternative when conventional routes of access have failed. However, the use of ultrasound to guide transhepatic access has not been reported in the literature. We performed a retrospective chart review. Patient characteristics, indications for catheterization, procedures performed, and complications were recorded. All patients who underwent transhepatic cardiac catheterization at Duke University Medical Center were included in this study. Eight patients underwent 12 catheterizations. The median age was 5.3 years (range, 9 months to 13 years) and median weight 18.7 kg (range, 7.1-44.8 kg). Seven catheterizations were diagnostic and 5 were interventional. There were no complications. Transhepatic access with ultrasound guidance is a safe and effective option for obtaining venous access for cardiac catheterization.

Is sedation safe during dynamic sleep fluoroscopy of children with obstructive sleep apnea?

OBJECTIVE: Airway compromise is considered a relative contraindication for pediatric sedation. This contraindication presents a paradoxical problem when patients require sedation in preparation for imaging performed to evaluate the cause of airway obstruction. We use dynamic sleep fluoroscopy in the evaluation of children who have obstructive sleep apnea. The purpose of this study was to evaluate the success and safety of a structured sedation program for dynamic sleep fluoroscopy. MATERIALS AND METHODS: Eighty consecutive dynamic sleep fluoroscopic studies were evaluated. The type of sedation used, success rate, complications related to the sedation, and characteristics of the children studied were reviewed. Patients were sedated in accordance with our departmental sedation program guidelines. Findings on fluoroscopy were correlated with episodes of oxygen desaturation or noisy breathing. RESULTS: In all 80 cases, dynamic sleep fluoroscopy was successfully performed. Seventy-two studies were performed, with sedation supervised by the radiologist. Four patients fell asleep without sedation. In four patients, sedation was performed by an anesthesiologist (preprocedural decision). Sixty-four children (80%) had complex medical problems, and 39 (49%) had a history of previous airway surgery. All studies were considered successful. Specific diagnoses were identified in 66 children (83%). No children suffered complications or required tracheal intubation. CONCLUSION: Children with airway compromise who are being evaluated for obstructive sleep apnea can be successfully and safely sedated for dynamic sleep fluoroscopy when a structured sedation program is used.

Frequency of right lower quadrant position of the sigmoid colon in infants and young children.

PURPOSE: To evaluate the frequency of right lower quadrant positioning of the sigmoid colon in infants and young children. MATERIALS AND METHODS: Findings in 169 patients who underwent enema examination were retrospectively reviewed. Sigmoid colon position was categorized as in the left or right lower quadrant or midline. Patients who had an anatomic abnormality that affected colonic position (eg, malrotation or abdominal mass) or had previously undergone abdominal surgery were excluded. The frequency of right lower quadrant sigmoid position was evaluated for a relationship with patient age (analysis of variance) and sex (chi(2) test). RESULTS: Patient ages were 1 day to 5 years (mean age, 13 months). The sigmoid colon was in the right lower quadrant in 74 (44%), in the left lower quadrant in 73 (43%), and in the midline in 18 (11%). The position was variable in one patient and indeterminate in three. When the sigmoid colon was within the right lower quadrant, it often extended laterally, overlying the position of the cecum and ascending colon. There were no significant correlations between right lower quadrant position and patient age (P =.262) and sex (P =.162). CONCLUSION: In children, the sigmoid colon is often within the right lower quadrant. Knowledge of this high frequency should reduce the likelihood of misinterpreting air within a redundant right-sided sigmoid colon as air within the cecum in children suspected of having abnormalities such as intussusception.

Minimizing radiation dose for pediatric body applications of single-detector helical CT: strategies at a large Children's Hospital.

Adjustments of the standard helical CT protocols for adults can result in reduced radiation dose when imaging children. It is the radiologist's responsibility to critically evaluate the CT techniques used at their institution. Adjustments to CT protocols should be made to choose the appropriate mA and pitch when imaging children.

Helical CT of the body: are settings adjusted for pediatric patients?

OBJECTIVE: Our objective was to determine whether adjustments related to patient age are made in the scanning parameters that are determinants of radiation dose for helical CT of pediatric patients. SUBJECTS AND METHODS: This prospective investigation included all body (chest and abdomen) helical CT examinations (n = 58) of neonates, infants, and children (n = 32) referred from outside institutions for whom radiologic consultation was requested. Information recorded included tube current, kilovoltage, collimation, and pitch. Examinations were arbitrarily grouped on the basis of the individual's age: group A, 0-4 years; group B, 5-8 years; group C, 9-12 years; and group D, 13-16 years old. RESULTS: Thirty-one percent (18/58) of the CT examinations were of the chest and 69% (40/58) were of the abdomen. Sixteen percent (9/58) of the CT examinations were combined chest and abdomen. In 22% (2/9) of these combined examinations, tube current was adjusted between the chest and abdomen CT; in one (11%) of these examinations, the tube current was higher for the chest than for the abdomen portion of the CT examination. The mean tube current setting for chest was 213 mA and was 206 mA for the abdomen, with no evident adjustment in tube current based on the age of the patient. Fifty-six percent of the examinations of neonates, infants, or children 8 years old or younger were performed at a collimation of greater than 5 mm and 53% of these examinations were performed using a pitch of 1.0. CONCLUSION: Pediatric helical CT parameters are not adjusted on the basis of the examination type or the age of the child. In particular, these results suggest that pediatric patients may be exposed to an unnecessarily high radiation dose during body CT.

Glossoptosis (posterior displacement of the tongue) during sleep: a frequent cause of sleep apnea in pediatric patients referred for dynamic sleep fluoroscopy.

OBJECTIVE: The purpose of this study was to evaluate the frequency of glossoptosis (posterior displacement of the tongue) as a cause of sleep apnea in pediatric patients referred for fluoroscopic sleep studies. MATERIALS AND METHODS: Seventy consecutive dynamic fluoroscopic sleep studies performed to evaluate sleep apnea were reviewed. All patients had been sedated and examined with lateral fluoroscopy during sleep. Anatomic changes in the airway were correlated with episodes of oxygen desaturation. Cases of glossoptosis, in which the tongue moved posteriorly during sleep and abutted the posterior pharynx, resulting in airway obstruction and oxygen desaturation, were identified. Associated factors were reviewed. RESULTS: Of 70 sleep studies reviewed, glossoptosis was the cause of airway obstruction in 17 patients (24%). Mean age in these 17 patients was 3 years (range, 5 days to 13 years). Seven of the 17 children were younger than 1 year old. Only three patients had no underlying medical problems. Four patients had macroglossia (Down syndrome, n = 3; duplicated tongue, n = 1) as a cause, and three patients had micro- or retrognathia (Pierre Robin syndrome, n = 2; Rubinstein-Taybi syndrome, n =1) as a cause. Six patients had neuromuscular abnormalities. CONCLUSION: Glossoptosis was a cause of airway obstruction in 25% of pediatric patients referred for fluoroscopic sleep studies. Attention to this anatomic region is important when evaluating children with sleep apnea.