Umbilical artery catheterization: a potential cause of refractory hypoglycemia

Refractory Hypoglycemia and Seizures as the Initial Presenting Manifestation of Empty Sella Syndrome

An empty sella is reported to occur in 5.5%–23.5% of the population and is usually asymptomatic. It can be associated with endocrine disturbances. We report a 48-year-old woman who presented with refractory hypoglycemia, seizures, and shock that improved with levothyroxine, hydrocortisone, and octreotide. Investigations revealed central hypothyroidism, hypoprolactinemia, low gonadotropins, normal C-peptide and a primary empty sella. Case reports of Sheehan syndrome with or without empty sella causing hypoglycemia have been reported occasionally. Our patient had never become pregnant. She had experienced premature menopause and symptoms suggestive of hypothyroidism for many years (without treatment) before her emergency department admission for altered sensorium. 

Anatomical Considerations in Obtaining Arterial Access

Arterial cannulation and catheterization are routine parts of medical care in intensive care units for neo nates, children, and adults. In this review I describe the anatomical landmarks that facilitate successful catheteri zation of the radial, ulnar, brachial, axillary, femoral, pos terior tibial, dorsalis pedis, umbilical, and superficial temporal arteries. Criteria for selection of each of these arteries for catheterization are discussed. Risks of arte rial puncture or catheterization include hemorrhage, thrombosis, infection, and vascular compromise to sur rounding structures. These risks are reviewed with ref erence to each of the arteries described.

Persistent hypoglycemia caused by umbilical arterial catheterization

Hypoglycemia as an umbilical artery catheter (UAC) complication is rare. We present a neonate with hyperinsulinemic hypoglycemia due to a high-positioned UAC used inadvertently for parenteral nutrition. The aim of this report is to increase physicians' awareness of the possibility of this rare complication.

Nurses' guide to early detection of umbilical arterial catheter complications in infants

Umbilical arterial catheters (UAC) are routinely used in the care of critically ill newborns. Complications related to UACs include vascular compromise, hemorrhage, complications related to malposition, severance of the catheter itself, and infection. This article is Part II in a series dedicated to assessing infants with an umbilical catheter. Part I focused on infants with umbilical venous catheters; this article will focus on the physical assessment relevant to infants with an UAC. Complications related to UACs can occur during any phase of treatment: insertion, while indwelling, or after discontinuing the catheter. Review of clinical signs of complications along with clinical photographs, will assist caregivers in promptly recognizing UAC-related complications.

Slow blood sampling from an umbilical artery catheter prevents a decrease in cerebral oxygenation in the preterm newborn

OBJECTIVE

Blood sampling from an umbilical artery catheter (UAC) placed in a high position (thoracal 6-9) has the potential to produce clinically significant changes in cerebral blood flow and, thereby, in cerebral oxygenation. This may contribute to cerebral impairment in preterm newborn infants. Therefore, we set up a study to determine the effects of different sampling speeds through a UAC on cerebral oxygenation in preterm infants.

METHODS

Thirty pairs of measurements were conducted on 20 preterm infants (median gestational age: 30.14 weeks; median birth weight: 1170 g). For each infant, 2 blood samplings (both 2.3 mL, including flush volume) through the UAC in high position were taken at 2 different speeds (20 and 40 seconds) in alternating sequence. Cerebral oxygenation was measured noninvasively by near-infrared spectroscopy. Concentration changes in cerebral oxygenated hemoglobin (O2Hb) and deoxygenated hemoglobin (HHb), along with the tissue oxygenation index (TOI; O2Hb/[O2Hb + HHb] x 100), were recorded while blood was withdrawn and subsequently reinfused.

RESULTS

A significant decrease in O2Hb and TOI occurred during blood sampling within 20 seconds (median DeltaO2Hb: -1.5 micromol/L; range: -4.1-2.3; median DeltaTOI: -0.6%; range: -6.3-2.3), whereas HHb increased (median DeltaHHb: 0.4 micromol/L, range: -1.1-3.9). No significant change was found in O2Hb, HHb, and TOI when sampling time was extended to 40 seconds.

CONCLUSION

Our results show that blood withdrawal over 20 seconds from a UAC in high position significantly decreases cerebral O2Hb and TOI in preterm infants. Prolonging sampling time to 40 seconds can prevent this phenomenon.

Neonatal vascular catheters and their complications

There has been an evolution in vascular access in the neonate. Newer types of materials and catheters, such as PICC lines and ECMO catheters, are now available. The frequency of line placement has increased, and radiologists now perform many of these procedures. This places the radiologist in the position of not only diagnosing complications, but actually causing them. Knowledge of these complications can help the practitioner avoid them and diagnose them as quickly as possible when they occur.