Neonatal vascular catheters and their complications

Complications of Peripheral Arterial Access in Preterm and Term Neonates: A Systematic Review

The aim of the study is to provide a comprehensive review of vascular complications secondary to peripheral arterial catheterization in preterm and term neonates. The systematic review consisted of searching PubMed, Scopus, Google Scholar, Cochrane Database of Systematic Reviews, and references of journals using pre-trialed MeSH terms and articles. Eight studies were included for full text analysis from 2,369 initial articles: six retrospective reviews and two prospective studies. Rate of complication was 8.6% and all complications were ischemic in nature. Complications most often occurred in neonates with pulmonary/cardiac comorbidities and lower gestational ages. No association was found for weight and sex of neonates. The radial artery site presented with lower rates of complication of 6% and the femoral presented with the highest (16%). Complications predominately occurred in catheter sizes larger than 22 gauge and most often within 1 day of insertion. A low rate of complications (7.4%) was observed in studies that used heparinized saline at the time of catheterization. This study demonstrates an increasing overall rate of complications with ischemia presenting as the most common complication. There seems to be an association between gestational age, comorbidities, site of catheter, size of catheter, and duration of catheter with such complications. This study also demonstrates the association between the use of heparinized saline and a reduction in rate of complications. The authors advocate for a national data collection tool of all pediatric arterial catheters and its complications to be able to analyze and work on best practice to minimize life changing iatrogenic complications.

Infraumbilical surgical retrieval of transected umbilical artery catheter in an 840 g newborn

An 840 g female baby born at 25 weeks gestation suffered a rare complication of umbilical arterial catheter (UAC) insertion, involving an accidental transection resulting in 11 cm of retained catheter inside the baby. Investigations revealed migration of the proximal tip of the catheter within 10 hours into the left subclavian artery.This complication is rare and has not frequently been described in the literature. Given the size and gestation of the patient, the risks and benefits of both conservative and non-conservative management were discussed in detail prior to any treatment decision being made. Effective multidisciplinary teamwork contributed to the successful removal of the UAC, done via a minimally invasive infraumbilical approach, associated with no further complications.

Joint time-frequency analysis of visible laser reflections in a sheep heart

Limited methods exist to confirm the position of cardiovascular devices in the superior vena cava or right atrium of the heart. The aim of this study was to design, test and validate the feasibility of whether an optical fiber-based instrument could accurately distinguish when a cardiovascular catheter was located in the superior vena cava vs in the right atrium. An optical fiber was placed in a cardiovascular catheter which was inserted into a living sheep and guided to the vicinity of the heart where diode laser-based reflection intensity data were simultaneously gathered from two visible wavelengths of light reflected from the venous and atrial tissue surfaces near the cavoatrial junction. The time series data were postoperatively analyzed using methods of joint time-frequency analysis and validated against catheter positions determined with fluoroscopy and ECG. The system was successful in distinguishing the location of the superior vena cava from the right atrium.

Umbilical venous catheter insertion depth estimation using birth weight versus surface measurement formula: a randomized controlled trial

OBJECTIVE

To determine if umbilical venous catheter (UVC) insertion depth estimated by surface measurement (SM) results in optimal catheter tip position on ultrasound as compared with formula using birth weight (BW).

METHODS

In this randomized controlled trial, eligible infants were randomized to UVC insertion depth estimated by SM or BW method. We compared proportion of optimum UVC position on ultrasound read by neonatologist masked with group assignment.

RESULTS

UVC was inserted to estimated depth in 164 of 200 enroled infants. There was no difference in the proportion of correctly positioned UVCs between the groups (SM 33/82 (40.2%) vs BW 27/82 (32.9%), p = 0.33). Among BW < 1000 g, SM method had higher correctly positioned UVC (43.7% vs 22.5%, p = 0.07).

CONCLUSION

There was no difference in the rate of optimally positioned UVC tip between the two methods for estimating UVC insertion depth. However, SM method results in more optimal positioning of UVC tip among BW < 1000 g infants.

Preparation of high-performance polyethylene tubes under the coexistence of silicone cross-linked polyethylene and rotation extrusion

In this study, the silicone cross-linked polyethylene (Si-XLPE) powder with better thermoplastic performance and abundant cross-linked network points was attained by using solid-state shear mechanochemical (S³M) technology and it was added into high-density polyethylene (HDPE) matrix to prepare Si-XLPE/HDPE tubes by a rotation extrusion rheometer. SEM and 2D-SAXS experiments showed that the presence of Si-XLPE and rotation extrusion facilitated the formation of stable shish-kebabs which deviated from the axial direction in polyethylene (PE) tubes. This result was interpreted that introduction of Si-XLPE in PE tubes provided abundant molecular cross-linked network structures, which suppressed the thermal movement and relaxation of oriented molecular chains owing to intermolecular interaction. Moreover, the axial and hoop flow field further promoted orientation of the permanent cross-linked network entanglement points and formation of more stable cluster-like shish structures in the off-axial direction during the rotation extrusion process. Besides, our experimental results had also ascertained that molecular orientation and shish-kebabs in off-axial direction should be the primary responsibility for the remarkable enhancement of hoop torsional strength in PE tubes. Hoop torsional strength of PE tubes adding Si-XLPE reached 19.58 MPa when the mandrel rotation rate was 30 r.p.m., while that of conventional extruded PE tubes was only 9.83 MPa. As a consequence, PE tubes with excellent performance were prepared under the combined effect of Si-XLPE and rotation extrusion.

Inadvertent Migration of Umbilical Venous Catheters Often Leads to Malposition

BACKGROUND

Migration of umbilical venous catheters (UVCs) has been described anecdotally.

OBJECTIVES

The aim of this paper was to investigate migration of UVCs using ultrasonography (US).

METHODS

In a prospective observational study, the position of UVCs was determined using serial US within 24 h, at midweek, and at the end of the week after umbilical catheterization. Migration was recorded in distance and direction. Malposition was defined as a position of the UVC in the heart (right atrium or more distal along the UVC-route), umbilicoportal confluence, or in the umbilical vein. UVC position determined by US was compared with chest X-rays (CXRs) when these were performed for standard care within the same period of 1 h.

RESULTS

Migration of UVCs was detected with US in 25/40 infants (63%) in 32 occasions, leading to malposition in 17/25 (68%) infants. UVCs migrated inwards in 18/32 (56%), leading to a position within the heart in 17/18 occasions. Most migrations occurred before Day 3 (21/32 [66%]). When a CXR was taken at the same time as US was performed (30 occasions), the assessment of the catheter-tip position differed in 23% of the occasions. When malposition was detected by US, this was detected on routinely performed CXRs in 11% of the occasions.

CONCLUSIONS

UVCs often migrate following insertion, often leading to malposition. Awareness for this is needed, and US is a feasible alternative for detecting malposition compared to CXRs and avoids additional radiation. Re-evaluation of the position of UVCs at least once, but within 24 h after placement, is recommended.

Accuracy of 11 formulae to guide umbilical arterial catheter tip placement in newborn infants

BACKGROUND

Umbilical arterial catheter (UAC) insertion is a common procedure in the neonatal intensive care unit (NICU). Correct placement of the tip of the UAC at first attempt minimises handling of the infant and reduces the risk of infection and complications. We aimed to determine the accuracy of 11 published formulae to guide UAC placement.

METHODS

This was a one-year prospective observational study in a tertiary NICU. Clinicians used their preferred formula for UAC insertion, with X-rays performed immediately post-procedure to check the tip position. Birth weight and measurements included in the 11 formulae were recorded within 48 hours. The gold standard insertion distance was defined as the distance from the abdominal wall to the mid-descending aorta, at T8 level on X-ray (range T6-T10). Insertion length using the 11 formulae was calculated and compared with this gold standard distance.

RESULTS

One hundred and three infants were included, with median (IQR) gestational age and weight of 28 (26-33.5) weeks and 980 (780-2045) g, respectively. The predicted value of the 11 formulae to place the UAC in correct position ranged from 51.0% to 73.8%. Formulae that involved direct body part measurements showed the highest predicted success rates, smallest mean difference from T8 and narrowest limits of agreement using the Bland-Altman method.

CONCLUSION

Success rates for accurate UAC placement are highest when formulae that involve body measurements are used. However, even the most accurate method would result in more than 25% of UACs needing manipulation to achieve an optimal position.

Postnatal dilatation of umbilical cord vessels and its impact on wall integrity: Prerequisite for the artificial placenta

INTRODUCTION

A lung assist device, which acts as an artificial placenta, can provide additional gas exchange for preterm and term newborns with respiratory failure. The concept of the lung assist device requires a large bore access via umbilical vessels to allow pumpless extracorporeal blood flow rates up to 30 mL/kg/min. After birth, constricted umbilical vessels need to be reopened for vascular access. The objective is to study the impact of umbilical vessel expansion on vessel integrity for achieving large bore access.

METHODS

Umbilical cords from healthy term deliveries were cannulated and dilatated with percutaneous transluminal angioplasty catheters in 1 mm increments from 4 to 8 mm for umbilical artery and from 4 to 15 mm for umbilical vein, n = 6 per expansion diameter. Paraffin-embedded transverse sections of dilated and control samples were HE & Van Gieson stained. Effects of dilatation, shown by splitting, were measured.

RESULTS

Umbilical vessel expansion led to concentric splitting, shown by areas devoid of extracellular matrix and nuclei in the tunica intima and media. No radial splitting was observed. Results suggest an expansion threshold of umbilical artery at 6 mm and umbilical vein at 7 mm, while maximal splitting was observed above this threshold (3.6 ± 0.8%, p = 0.043 for umbilical artery 7 mm and 6.3 ± 1.8%, p = 0.048 for umbilical vein 8 mm). Endothelial cell sloughing was present in all dilated samples but not in the control samples.

CONCLUSION

The suggested thresholds for safe expansions are similar to in utero umbilical vessel diameters and demonstrate a proof of concept for attaining large bore access for the lung assist device.

Role of ultrasound for central catheter tip localization in neonates: a review of the current evidence

Central catheters are known as "life lines" in intensive care units and are used frequently in neonatal intensive care unit (NICU) for multiple indications. The central catheters used in NICU includes umbilical venous catheter (UVC), umbilical arterial catheter (UAC) and peripherally inserted central catheter (PICC) lines. The tip of these central lines needs to be in a correct position as malpositioned central line tips lead to many neonatal complications. Radiograph either abdomen or chest is the most widely used modality for locating the tip of the central catheter. There are many disadvantages of radiographic confirmation of tip position and recently ultrasound (USG)/echocardiography has been used for localization of catheter tip. USG provides real-time assessment of the tip position with other added advantages like no radiation exposure, need for minimal training for performing USG, minimal handling of the neonate, identification of migration of central lines and making repositioning of central lines under USG guidance. The present evidence supports the use of USG/Echo for localization of central catheter tip and USG has shown to have good sensitivity, specificity, positive predictive value and negative predictive value when compared with a radiograph. In this review, we discuss about the role of USG/Echo in the identification of tip of central catheters in neonatal care.

Perforations associated with peripherally inserted central catheters in a neonatal population

BACKGROUND

Peripherally inserted central catheters (PICCs) are increasingly used in neonates but perforations can result in devastating complications such as pericardial and pleural effusions. Identifying risk factors may guide surveillance and reduce morbidity and mortality.

OBJECTIVE

To determine the risk factors for PICC perforation in neonates.

MATERIALS AND METHODS

Retrospective case:control (1:2) study of neonates admitted between 2004-2014. Charts and imaging were reviewed for clinical and therapeutic risk factors.

RESULTS

Among 3,454 PICCs, 15 cases of perforation (incidence 0.4%, 5 pericardial effusions, 10 pleural effusions) were matched to 30 controls, based on gestation and insertion date. Timing of perforations post-insertion was median 4 days for pericardial effusions and 21.5 days for pleural effusions. A risk factor for pericardial effusion was lower weight at PICC insertion compared with controls. There were no statistically significant differences between cases and controls in catheter material, insertion site, PICC size and lumen number. Among upper limb PICCs, pericardial effusions were associated with tip positions more proximal to the heart at insertion (P=0.005) and at perforation (P=0.008), compared with controls. Pleural effusions were associated with tip positions more distal from the heart at perforation (P=0.008). Within 48 h before perforation, high/medium risk infusions included total parenteral nutrition (100% cases vs. 56.7% controls, P=0.002) and vancomycin (60% cases vs. 23.3% controls, P=0.02).

CONCLUSION

PICC-associated pericardial effusions and pleural effusions are rare but inherent risks and can occur at any time after insertion. Risk factors and etiologies are multifactorial, but PICC tip position may be a modifiable risk factor. To mitigate this risk, we have developed and disseminated guidelines for target PICC positions and routinely do radiographs to monitor PICCs for migration and malposition in our NICU. The increased knowledge of risk profiles from this study has helped focus surveillance efforts and facilitate early recognition and treatment.

Non-central peripherally inserted central catheters in neonatal intensive care: complication rates and longevity of catheters relative to tip position

BACKGROUND

Peripherally inserted central catheters (PICCs) represent a mainstay of intravascular access in the neonatal intensive care setting when long-term vascular access is needed. Ideally, PICCs should be inserted and maintained in a central position with the tip ending in the superior or inferior vena cava. This is not always achievable, and sometimes the tip remains in a peripheral location. Higher complication rates have been reported with non-central PICCs; however these findings have not been confirmed in a solely neonatal series and PICCs with tips in peripheral veins have not been studied.

OBJECTIVE

To compare complication rates and length of catheter duration related to PICC position in neonates.

MATERIALS AND METHODS

We conducted a retrospective analysis of all PICCs inserted in term and preterm infants in a tertiary neonatal intensive care unit between May 2007 and December 2009. A single pediatric radiologist reinterpreted the catheter tip site on initial anteroposterior (AP) chest radiographs and categorized sites as central (superior vena cava, inferior vena cava, brachiocephalic vein), intermediate (subclavian, axillary, common or external iliac veins), or peripheral (veins peripheral to axillary or external iliac veins). We analyzed complication rates and length of catheter duration among the three categories.

RESULTS

We collected data on a total of 176 PICCs. Infants with PICCs in a central location had a significantly lower complication rate (18/97, 19%) than those with the PICC tip in an intermediate (24/64, 38%) or peripheral (9/15, 60%) locations (P=0.0003). Length of catheter duration was noted to be longest with central, intermediate with intermediate, and shortest with peripheral PICC tip locations (17.7±14.8 days for central vs. 11.4±10.7 days for intermediate vs. 5.4±2.5 days for peripheral, P=0.0003).

CONCLUSION

A central location is ideal for the tip of a PICC. When this is not achievable, an intermediate location is preferable to a more peripheral position.

The value of real-time continuous glucose monitoring in premature infants of diabetic mothers

To determine the feasibility of using a real-time continuous glucose monitoring system (RTGMS) in intensive care units, our study focus on preterm infants with diabetic mothers owing to their high risk of blood sugar abnormalities. Thirty preterm babies (M = 15 and F = 15; ≤ 36 week gestation age) were studied from within 72 hours of delivery. These babies were admitted to the newborn intensive care and were further categorized into groups based on whether their mothers with or without diabetic mellitus. Blood sugar levels were monitored by both RTGMS and the traditional intermittent arterial line (A-Line) glucose method. Continuous glucose monitoring were well tolerated in 30 infants. There were good consistency between RTGMS and A-Line glucose concentration measurements. Of the preterm infants, 33.33% experienced abnormal glucose levels (hypoglycemia or hyperglycemia) between the checkpoint intervals of the intermittent A-Line blood sugar measurements. RTGM showed advantages with regards to reduced pain, greater comfort, the provision of real-time information, high sensitivity (94.59%) and specificity (97.87%) in discovering abnormalities of blood sugar, which are especially valuable for premature infants of diabetic mothers. RTGMS is comparable to A-line measurement for identifying fluctuations in blood glucose in premature infants. RTGMS detects more episodes of abnormal glucose concentration than intermittent A-line blood glucose measurement. High risk infants, especially premature infants with diabetic mothers, should receive more intensive blood sugar level checks by using continuous RTGMS.

Comparison of methods and formulas used in umbilical venous catheter placement

AIM

Central venous access is frequently provided by way of umbilical venous catheter placement in critically ill newborns. This study compared the methods of Dunn, Shukla-Ferrara, and Revised Shukla-Ferrara in determining the appropriate insertion length of umbilical vein catheters.

MATERIAL AND METHODS

This prospective observational study was carried out in 121 newborns with umbilical venous catheter, group 1 (n=41) used Dunn method, group 2 (n=40) used the Shukla-Ferrara formula, and group 3 used revised Shukla-Ferrara formula (n=40). Catheter tip position was evaluated with an anterior-posterior chest radiograph after insertion of the umbilical venous catheter. The ideal position for the umbilical venous catheter was defined as the catheter tip being visible between the 9th and 10th thoracic vertebrae on an anterior-posterior chest radiograph. The position of the umbilical venous catheter was considered too high if the tip of the catheter was higher than the 9th thoracic vertebra and too low if the tip was below the 10th thoracic vertebra. The following data were collected: appropriate, inappropriate (low, high) placement, and complications of umbilical venous catheterization.

RESULTS

In the Shukla-Ferrara group, 53% (17/32) of umbilical venous catheters were placed directly in the appropriate position, compared with 40% (12/30) in the revised Shukla-Ferrara group and 38% (11/29) in the Dunn method group. Umbilical venous catheter-related complications developed in two patients, thrombus in one, and catheter-related blood stream infection in the other.

CONCLUSIONS

This study showed that the Shukla-Ferrara formula is more accurate in predicting the insertion length for umbilical venous catheters, though statistical significance was not found. Further studies with larger samples are needed on this topic.

Neonatal atrial flutter after insertion of an intracardiac umbilical venous catheter

Objective:

To describe a case of neonatal atrial flutter after the insertion of an intracardiac umbilical venous catheter, reporting the clinical presentation and reviewing the literature on this subject.

Case description:

A late-preterm newborn, born at 35 weeks of gestational age to a diabetic mother and large for gestational age, with respiratory distress and rule-out sepsis, required an umbilical venous access. After the insertion of the umbilical venous catheter, the patient presented with tachycardia. Chest radiography showed that the catheter was placed in the position that corresponds to the left atrium, and traction was applied. The patient persisted with tachycardia, and an electrocardiogram showed atrial flutter. As the patient was hemodynamically unstable, electric cardioversion was successfully applied.

Comments:

The association between atrial arrhythmias and misplaced umbilical catheters has been described in the literature, but in this case, it is noteworthy that the patient was an infant born to a diabetic mother, which consists in another risk factor for heart arrhythmias. Isolated atrial flutter is a rare tachyarrhythmia in the neonatal period and its identification is essential to establish early treatment and prevent systemic complications and even death.

Fabrication and characterization of medical grade polyurethane composite catheters for near-infrared imaging

Peripherally inserted central catheters (PICCs) are hollow polymeric tubes that transport nutrients, blood and medications to neonates. To determine proper PICC placement, frequent X-ray imaging of neonates is performed. Because X-rays pose severe health risks to neonates, safer alternatives are needed. We hypothesize that near infrared (NIR) polymer composites can be fabricated into catheters by incorporating a fluorescent dye (IRDye 800CW) and visualized using NIR imaging. To fabricate catheters, polymer and dye are dry mixed and pressed, sectioned, and extruded to produce hollow tubes. We analyzed surface roughness, stiffness, dye retention, NIR contrast intensity, and biocompatibility. The extrusion process did not significantly alter the mechanical properties of the polymer composites. Over a period of 23 days, only 6.35 ± 5.08% dye leached out of catheters. The addition of 0.025 wt% dye resulted in a 14-fold contrast enhancement producing clear PICC images at 1 cm under a tissue equivalent. The addition of IRDye 800CW did not alter the biocompatibility of the polymer and did not increase adhesion of cells to the surface. We successfully demonstrated that catheters can be imaged without the use of harmful radiation and still maintain the same properties as the unaltered medical grade equivalent.

Cardiac tamponade in a neonate: a dreadful condition--need for functional echo

Cardiac tamponade is a clinical emergency. Detection of a swinging heart rate is one of the earliest markers of large pericardial effusion, in which the four cardiac chambers are free to float in a phasic manner. We present a case of a preterm baby, one of the twins, who developed sudden onset of deterioration in the form of swinging heart rate, fluctuation in blood pressure and desaturation, requiring emergency intubation and inotropic support. Bedside functional echo was performed, which demonstrated cardiac tamponade; an immediate echocardiography-guided tap was initiated and fluid was aspirated from the pericardial space.

Revised formula to determine the insertion length of umbilical vein catheters

The method of Shukla is commonly used to predict the insertion length of umbilical vein catheters (UVCs) but often leads to over-insertion. Malposition of UVCs can lead to complications. In this study, we compared the formula of Shukla, i.e., (3 x birthweight in kg + 9) / 2 + 1 cm with a revised formula, i.e., (3 x birthweight in kg + 9) / 2 cm in determining the insertion length of UVCs. A cohort where the revised formula was used for UVC placement (revised group) was compared with a historical cohort using the conventional formula (Shukla group). We evaluated the position of UVCs stated as the corresponding vertebra level with a radiograph of the infant's chest and abdomen immediately after insertion in both groups. Positioning of the catheter tip above the ninth or below the tenth thoracic vertebra was considered too high or too low, respectively. Median position of 93 UVCs placed according to Shukla was lower (seventh thoracic vertebra, interquartile range (IQR) 6-9) when compared to 92 UVCs placed according to the revised formula (eighth thoracic vertebra (IQR 7-9)). UVCs were more often over-inserted using the Shukla formula (73%) when compared to the revised formula (54%). One UVC in the Shukla group (1%) and two UVCs in the revised group (2%) were placed too low (p = NS).

CONCLUSION

The revised formula reduces the rate of over-insertion of UVCs without increasing the rate of inadequate lower positioning.

Peripherally inserted central catheter tip position and risk of associated complications in neonates

OBJECTIVE

To characterize the relationship between peripherally inserted central catheters (PICC) tip positions and associated complications in neonates.

STUDY DESIGN

Catheter tip position for 319 infants was classified into superior vena cava (SVC, n=131), inferior vena cava (IVC, n=72), brachiocephalic (BC, n=59), midclavicular (MC, n=49) or iliac. Duration of catheter stay and complication profile was compared between central (SVC/IVC) vs non-central PICC, and between SVC vs IVC, SVC vs BC and SVC vs MC. Kaplan-Meier survival analysis and regression models were used.

RESULT

Overall length of catheter stay was similar between central and non-central group. Non-central catheters (n=116) had higher complication rates (47 vs 29%; P=0.001), non-elective removals (45 vs 27%; P=0.002) and shorter time to complication (6.2 vs 11.4 days; P=0.043). This difference was primarily due to the complications encountered in MC group, which had the highest rate of infiltration (P<0.001) and mechanical complications while outcomes were similar among other subgroups. Interestingly, catheter survival probability was similar in all groups for first 4 days. Rate and types of blood stream infections were not related to catheter tip position.

CONCLUSION

Non-central PICCs are associated with higher rates of infiltration and mechanical complications when the tip is in MC region. BC catheters may have comparable outcomes to SVC in neonates. A careful risk-benefit analysis is warranted when MC catheters are used in neonates.

Central venous catheters in premature babies: radiological evaluation, malpositioning and complications

Central venous catheters are important in the care for prematurely born children in the neonatal intensive care unit. The purpose of this pictorial essay is to illustrate correct positioning, malpositioning and possible complications of such devices.

Cardiac tamponade due to umbilical venous catheter in the newborn

With more and more extreme premature and very low-birth weight babies being resuscitated, umbilical central venous catheterisation is now being used more frequently in neonatal intensive care. The authors present a case of cardiac tamponade following umbilical venous catheterisation in a neonate, an uncommon, yet potentially fatal complication. The patient was diagnosed at the appropriate time by echocardiography and urgent pericardiocentesis proved lifesaving.

Modified insertion of a peripherally inserted central catheter: taking the chest radiograph earlier

Placement of the tip of a peripherally inserted central catheter in the lower third of the superior vena cava is essential to minimize the risk of complications. Sometimes, however, the catheter tip cannot be localized clearly on the chest radiograph, and repositioning a catheter at bedside is difficult, sometimes impossible. A chest radiograph obtained just after the catheter is inserted, before the guidewire is removed, can be helpful. With the guidewire in the catheter, the catheter and its tip can be seen clearly on the radiograph. If the catheter was inserted via the wrong route or the tip is not at the appropriate location, the catheter can be repositioned easily with the guidewire in it. Between January 1, 2007, and May 31, 2009, 225 catheters were placed by using this method in our department. Of these, 33 tips (14.7%) were initially malpositioned. The tips of all these catheters were repositioned in the lower third of the superior vena cava by using this method. No catheter was exchanged or removed. The infection rate for catheter placement did not increase when this method was used. This modification facilitates accurate location of the catheter tip on the chest radiograph, making it easy to correct any malposition (by withdrawing, advancing, or even reinserting the catheter after withdrawal).

Iatrogenic skin injury in the neonatal intensive care unit

Although neonatal care has become more and more meticulous with significant changes in technology in the neonatal intensive care unit (NICU) in the past 50 years, iatrogenic cutaneous injuries continue to occur. Although the incidence of severe injuries is decreasing because the more difficult procedures are being replaced by improved techniques, skin injuries have not yet been completely eliminated. However, the nature and causes of cutaneous injuries have changed, and the injuries are frequent but generally minor. The major risk factors are low birth weight, gestational age, length of stay, a central venous line, mechanical ventilation, and support with continuous positive airway pressure. The rate of iatrogenic events is about 57% at gestational ages of 24-27 weeks, compared with 3% at term. There are no current comprehensive reviews of iatrogenic cutaneous injury. The purpose of this review is to describe the iatrogenic cutaneous injuries that may occur in the newborns as a consequence of perinatal and postnatal medical procedures. With increased survival of extremely-low-birth-weight (ELBW) infants and changing modes of management in the NICU, neonatologists must make every effort to recognize injuries and prevent their occurrence in the NICU.

Poor accuracy of methods currently used to determine umbilical catheter insertion length

This study compares the methods of Dunn and Shukla in determining the appropriate insertion length of umbilical catheters. In July 2007, we changed our policy for umbilical catheter insertions from the method of Dunn to the method of Shukla. We report our percentage of inaccurate placement of umbilical-vein catheters (UVCs) and umbilical-artery catheters (UACs) before and after the change of policy. In the Dunn-group, 41% (28/69) of UVCs were placed directly in the correct position against 24% (20/84) in the Shukla-group. The position of the catheter-tip of UVCs in the Dunn-group and the Shukla-group was too high in 57% (39/69) and 75% (63/84) of neonates, respectively. UACs in the Dunn-group were placed directly in the correct position in 63% (24/38) compared to the 87% (39/45) of cases in Shukla-group. The position of the catheter-tip of UACs in the Dunn-group and the Shukla-group was too high in 34% (13/38) and 13% (6/45) of neonates, respectively. In conclusion, the Dunn-method is more accurate than the Shukla-method in predicting the insertion length for UVCs, whereas the Shukla-method is more accurate for UACs.

Are supine chest and abdominal radiographs the best way to confirm PICC placement in neonates?

BACKGROUND

Peripherally inserted central catheters (PICCs) are commonly used in NICUs. Although they have many benefits, they also have many potential complications. Confirming catheter tip position is essential to decreasing complications, but the best method to achieve confirmation is unclear.

OBJECTIVES

Literature review for studies that address line position confirmation to assist health care providers in evaluating the available research and to identify gaps in the literature.

METHOD

A literature search of four major databases followed by an ancestry approach was performed. Articles reviewed specifically discuss PICC lines and PICC line placement confirmation.

RESULTS

Data on confirming PICC placement were lacking. Fluoroscopic placement is ideal, but cannot be done at the bedside and is costly. Supine chest radiograph is the most widely used method and is convenient, but when line tip position is unclear, contrast or ultrasound confirmation can be used. When PICC lines are placed in the saphenous vein, infants may benefit from supine and lateral abdominal radiographs to ensure placement in the inferior vena cava.

DISCUSSION

More studies are needed to generalize findings. PICC line tips should be located in the superior vena cava or inferior vena cava close to the junction with the right atrium (0.5-1 cm outside of the cardiac chambers in premature infants and 1-2 cm outside of the cardiac chambers in larger infants). Arm position is very important when performing radiographs for placement because movement of the arm can cause migration of the catheter. There is also significant inter-observer variability when identifying line tip position.

Complications of umbilical artery catheterization in a model of extreme prematurity

OBJECTIVE

Umbilical artery catheter (UAC) use is common in the management of critically ill neonates; however, little information exists regarding the anatomic and vascular effects of UAC placement in premature newborns.

STUDY DESIGN

Baboons were delivered at 125 days of gestation (term=185 days), treated with surfactant, had UACs placed and were ventilated for either 6 or 14 days. Animals were assigned to short-term (6 days, n=6) and long-term (14 days, n=30) UAC placement. At necropsy, aortas were removed with UACs still in place. Histological examination of upper, middle and lower aorta specimens stained with hematoxylin and eosin and immunolabeled to detect smooth muscle (alpha-actin) was carried out in a blinded manner. Controls were delivered at 125, 140 and 185 days and the aortas acquired immediately after birth. None of the non-catheterized control animals (125 days, n=4; 140 days, n=5; and 185 days, n=5) had aortic vessel thrombi or vascular wall abnormalities.

RESULT

All 6 animals with short-term (6/6, 100%) and 18 animals with long-term (18/30, 60%) UAC placement displayed aortic thrombi and neointimal proliferation of the vascular wall. The majority (60%) of analyzed animals with UAC placement displaying neointimal hyperplasia were immunopositive for alpha-actin, indicating the presence of smooth muscle in these lesions.

CONCLUSION

Our findings suggest that both short- and long-term UAC use is associated with aortic wall pathological abnormalities compared with control animals. This study emphasizes the judicious use and early removal of UACs if possible in order to potentially prevent significant hemostatic and aortic wall vascular complications.

Cardiac complications in preterm infants with percutaneous long lines: the importance of early diagnosis

Percutaneous long lines, routinely used in preterm infants, can be associated with several cardiac complications such as pericardial effusion and consequent cardiac tamponade. We report three patients with pericardial effusion highlighting the importance of cardiac ultrasound monitoring to both early diagnosis and treatment.

Calcified aneurysm of the abdominal aorta 12 years after umbilical artery catheterization

We report a 12-year-old boy who presented with abdominal pain and who was found to have an aneurysm of the abdominal aorta (AAA). The patient was born from a quadruplet pregnancy induced by in vitro fertilization. Postnatal transient respiratory distress required assisted ventilation that had been monitored by two consecutive umbilical arterial catheters (UAC). AAA is a rare condition in childhood. Infection and/or trauma are known to be the most frequent causes. Most of the reported cases have occurred in children in whom a UAC had been placed during the neonatal period. In this patient the delay between UAC placement and diagnosis was considerable. At the time of this report the patient had remained well during a follow-up of 8 years after treatment.

Achados normais no exame radiológico de tórax do recém-nascido

O objetivo deste trabalho é descrever os achados normais na radiografia de tórax do recém-nascido, os critérios usados para avaliar a qualidade técnica do exame, assim como o posicionamento correto de sondas, cânulas e cateteres, enfatizando as especificidades dos achados radiológicos relacionados à faixa etária do paciente. No período neonatal, a imagem cardíaca é mais proeminente em virtude da conversão da circulação fetal, as dobras de pele e as variações da imagem tímica podem simular doenças, a avaliação do posicionamento adequado de sondas e cateteres evita iatrogenias, o padrão gasoso intestinal apresenta mudanças relacionadas ao número de horas de vida do paciente e a presença dos núcleos de ossificação secundários na extremidade proximal dos úmeros e processo coracóide está associada com a idade gestacional a termo do recém-nascido, representando, portanto, um sinal radiológico de desenvolvimento ósseo normal. O conhecimento das particularidades e dos aspectos radiológicos normais no tórax do recém-nascido evita diagnósticos equivocados, reduz as iatrogenias e representa um valioso suporte no diagnóstico e no acompanhamento clínico destes pacientes.

Image-guided interventions in neonates

Minimally invasive interventional radiological procedures can be invaluable in the care of neonates and infants. These procedures have proven to be useful in a wide variety of clinical situations, improving patient care, comfort and safety. Most techniques in adult interventional radiology have been adapted for use in pediatric patients, covering the spectrum of diagnostic and therapeutic intervention. Procedural techniques are similar, but require considerations of patient size, sedation, and support personnel in order to render optimal care. Proper physician training is imperative to provide the necessary confidence and expertise, and post-procedural follow-up is required to maximize positive outcomes. This paper discusses many of the procedures that may be performed in neonates, and offers suggestions and techniques for successful outcomes.

Cannula tip intravascular migration in an infant

In infants, the tip of a cannula is sometimes used as introducer during peripherally inserted central catheters placement. We report a rare complication of this procedure, characterized by intravascular migration of the cannula tip during peripheral insertion of a central venous catheter. We review this unlikely complication and treatment options.

The neonatal chest

Lung diseases represent one of the most life threatening conditions in the newborn. Important progresses in modern perinatal care has resulted in a significantly improved survival and decreased morbidity, in both term and preterm infants. Most of these improvements are directly related to the better management of neonatal lung conditions, and infants of very low gestational ages are now surviving. This article reviews the common spectrum of diseases of the neonatal lung, including medical and surgical conditions, with emphasis to the radiological contribution in the evaluation and management of these infants. Imaging evaluation of the neonatal chest, including the assessment of catheters, lines and tubes are presented.

Influence of arm movement on central tip location of peripherally inserted central catheters (PICCs)

BACKGROUND

PICCs are increasingly employed in children. Some of their risks relate to the location of the central tip. Despite care when placing lines, they sometimes move.

OBJECTIVE

To evaluate the influence of arm movement on the central tip location of PICCs placed in children.

MATERIALS AND METHODS

The central tip location of PICCs was studied in 85 children, with the arm placed in six positions. The variables of side, vein, site and arm position were examined to measure the direction and range of tip movement.

RESULTS

The side, site or vein used did not influence the range of movement of the central tip. Change in position of the arm had a significant influence on the central tip location, moving it an average of 2.2 rib spaces, a maximum of 3.5 ribs. Elbow bending and adduction of the arm caused the central tip to move deeper into the chest, compared to when the arm was straight and abducted 90 degrees .

CONCLUSION

Arm position is the significant variable influencing PICC movement. Side, site and vein do not influence the range of movement significantly. Most PICCs descend deeper into the chest with arm adduction and elbow bending.

The superior vena cava syndrome: clinical characteristics and evolving etiology

Malignancy is the most common cause of the superior vena cava (SVC) syndrome. With the increasing use of intravascular devices, the incidence of the SVC syndrome arising from benign etiologies is increasing. We reviewed the etiology and outcome of 78 patients with SVC syndrome over 5 years. Malignancy was the etiology in 60% of the cases, and bronchogenic carcinoma was the most common malignancy. Small cell and non-small cell lung cancer accounted for 17 (22%) and 19 (24%) cases, respectively, but a higher percentage of patients with small-cell lung cancer developed the syndrome (6% vs 1%). Lymphoma and germ cell tumors were other significant malignant causes (8% and 3% of cases, respectively). An intravascular device was the most common etiology in benign cases (22 of 31 cases; 71%), with fibrosing mediastinitis the second most common benign etiology (6 cases). The most frequent signs and symptoms were face or neck swelling (82%), upper extremity swelling (68%), dyspnea (66%), cough (50%), and dilated chest vein collaterals (38%). Dyspnea at rest, cough, and chest pain were more frequent in the patients with malignancy. Procedures performed for diagnostic or treatment purposes did not increase morbidity or mortality.

Multiple versus single lumen umbilical venous catheters for newborn infants

BACKGROUND

Multiple lumen umbilical venous catheters (ML-UVCs) instead of single lumen UVCs (SL-UVCs) may decrease the need for additional venous lines. Although it seems self-evident that ML-UVCs would reduce the need of additional venous lines, the rates of associated complications might be different.

OBJECTIVES

To compare the effectiveness and the safety of ML-UVCs versus SL-UVCs in terms of need of additional vascular access, rates of complications, morbidity and mortality in newborn infants.

SEARCH STRATEGY

Randomized and quasi-randomized trials were identified by searching the MEDLINE (1966 - February 2005), EMBASE (1980- February 2005), CINAHL (1982 - February 2005), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 4, 2004) and Science Direct (subject area: medicine, journal and abstract database; 1967 to February 2005). Literature search also included a manual search of the abstracts of scientific meetings published in Pediatric Research (1990-2004). Additional citations were sought using references in articles retrieved from searches. Subject experts were contacted to identify the unpublished and ongoing studies.

SELECTION CRITERIA

Randomized and quasi-randomized controlled clinical trials comparing safety and efficacy of multiple versus single lumen umbilical venous catheter in neonates (both term and preterm) who were in need of umbilical venous catheter insertion for vascular access in first four weeks of life.

DATA COLLECTION AND ANALYSIS

Each review author performed data extraction independently and differences were resolved by discussion. The following outcomes were determined: total number of additional peripheral intravenous lines per baby in first week and first four weeks of life, total number of additional percutaneously and surgically placed central venous lines per baby in first four weeks of life, and other safety and efficacy measures. The treatment effect estimators used were RR, RD, and WMD when appropriate along with their 95% CI. If RD was statistically significant, then number needed to treat (NNT) or number needed to harm (NNH) was calculated.

MAIN RESULTS

Three studies qualified for inclusion in this review (Khilnani 1991; Loisel 1996; Soupre 1998). There was a decrease in the ML-UVCs group in the number of additional PIVs used in the first week of life [WMD -1.42, (95% CI -1.74, -1.10), p<0.00001, number of infants (n) = 99]. There was no significant effect on the number of additional PIVs used in the first four weeks of life [MD -2.30, (95% CI -6.65, 2.05), n=36]. There was an increase in catheter malfunction in the ML-UVCs group [typical RR 3.69 (95% CI 0.99, 13.81), p=0.05; RD 0.15 (95% CI 0.03, 0.27), p=0.01; NNH was 7, 95% CI 4, 33; n=99]. The following outcomes were not significantly different in the two groups: clinical sepsis, catheter related blood stream infection, catheter-associated thrombosis, complications related to catheter malposition in heart and great vessels, NEC and early neonatal mortality.

AUTHORS' CONCLUSIONS

The use of ML-UVCs in comparison to SL-UVCs in neonates is associated with decrease in the usage of PIVs in first week of life, but an increase in catheter malfunctions. As the quality of included randomized studies is poor and the estimates of clinically important complications are imprecise, no firm recommendations can be made regarding the choice of UVC. Adequately powered, properly randomized and properly blinded controlled trials are needed that address the effectiveness and safety of ML-UVCs (double and triple lumen) in comparison to SL-UVCs. These studies should also address the impact of type of catheter material.

Umbilical vein catheterization under electrocardiogram guidance

BACKGROUND

In the neonate, umbilical venous catheters (UVC) are inserted and advanced blindly to a predetermined length from the umbilicus. The reported rates for UVC misplacement into the liver (and occasionally the spleen) range from 20 to 37%. Radiographs are routinely used to confirm the positioning of UVCs. This involves movement of often critically ill infants, as well as radiation exposure. This pilot study examines the potential value of confirming UVC placement in neonates using ECG.

METHODS

In critically ill neonates, a conductive Johans ECG adapter was connected to a UVC. A satisfactory tracing (lead II) was obtained (right arm lead connected to the adapter) when the UVC was filled with saline solution allowing the catheter tip to become a unipolar ECG electrode. The UVC was then advanced from the umbilicus until the tip reached the inferior vena cava (IVC) within the thoracic region, as demonstrated by appearance of normal sized QRS complexes with small P-waves. A small QRS indicated the catheter was below the diaphragm. The appearance of a tall positive P-wave indicated the tip was at the right atrium level. The UVC was then withdrawn until the P-wave size returned to normal. The final UVC position was later confirmed by X-ray.

RESULTS

Eight neonates were studied. The figure shows typical ECG tracings when the UVC was placed in the liver, IVC, and right atrium, respectively. Three malpositioned catheters were detected (2 into liver and 1 into spleen).

CONCLUSIONS

Based on these cases, the insertion of UVCs in neonates can be guided with ECG by observing sequential and characteristic alterations in P-waves and QRS complexes, thereby reducing the use of X-rays. In addition, this technique could prove to be beneficial in remote healthcare facilities where X-ray machines may not be readily available and quick intravenous access is required to transport sick neonates to major centers.

Placement of Peripherally Inserted Central Catheters without Fluoroscopy in Children: Initial Catheter Tip Position

PURPOSE

To determine how often placement of peripherally inserted central catheters (PICCs) without imaging guidance results in an initially correct central venous catheter tip location.

MATERIALS AND METHODS

This study was approved by the hospital's institutional review board, which waived the requirement for informed consent. In a children's hospital, 843 PICCs were placed in 698 patients (age range, 0 days to 26 years; mean, 6.9 years) during a 14-month study period. All PICCs were placed by a specialized team of PICC nurses and interventional radiology technologists in an angiography suite with the supervision of pediatric interventional radiologists. All catheters were threaded blindly to a previously estimated length by either a PICC nurse or a pediatric interventional radiologist, according to National Association of Vascular Access Networks guidelines, and the initial PICC tip location was then determined by means of spot fluoroscopy. PICC tips were regarded as central if they resided anywhere within the superior vena cava (SVC). All catheters were then manipulated with intermittent fluoroscopic guidance to achieve a final central position in the distal third of the SVC. A chi2 test was used to compare initial and final PICC tip locations according to patient age, catheter size, accessed vein, and need for radiologist assistance. A t test was used to compare procedure time with and without radiologist assistance.

RESULTS

Analysis included 843 consecutively placed pediatric PICCs, of which 723 (85.8%) had a noncentral initial PICC tip position and required additional manipulation. After catheter repositioning performed with intermittent fluoroscopic guidance, a final central PICC tip location was achieved in 760 PICCs (90.2%).

CONCLUSION

Pediatric PICC placement without fluoroscopic guidance required catheter manipulation of initial PICC tip position in 723 cases (85.8%). PICC placement with fluoroscopic guidance is highly successful, and the authors believe it is best performed in an angiography suite.

Central venous catheters and cardiac tamponade in preterm infants

OBJECTIVE

To determine the incidence of cardiac tamponade related to peripherally inserted central catheters in newborns weighing less than 1,500 g during the past 8 years and to provide guidelines in order to avoid death due to this complication.

DESIGN

Retrospective case review.

SETTING

Tertiary level neonatal intensive care unit.

PATIENTS AND PARTICIPANTS

Retrospective study of a total of 280 peripherally inserted central catheters positioned in 258 preterm newborns.

MEASUREMENTS AND RESULTS

Five cardiac tamponades were observed, giving an incidence of 1.8%. Data from our cases included clinical presentation and outcome, biochemical evaluation of pericardial fluid, days until diagnosis, central catheters characteristics, insertion site and tip placement site.

INTERVENTION

Two of the infants did not respond to resuscitation measures including cardiac massage and the administration of epinephrine. Post-mortem examination revealed the intrapericardial accumulation of protein and lipid alimentation solution. The other three patients were successfully resuscitated by timely pericardiocentesis. All five infants had routinely performed serial radiographs and cardiac color Doppler ultrasonography that showed correct catheter tip placement.

CONCLUSIONS

The incidence of cardiac tamponade could be reduced by following specific guidelines. The possibility of tamponade must be kept in mind during the resuscitation of any preterm infant with a peripherally inserted central catheter in place who develops symptoms of shock or sudden bradycardia. Our experience shows that even preterm infants with cardiac tamponade can be successfully resuscitated by timely pericardiocentesis in most cases.

Long line positioning in neonates: does computed radiography improve visibility?

OBJECTIVES

To assess the use of soft copy reporting of computed radiography (CR) images in determining intravenous long line tip position in neonates and compare visibility rates with hard copy printed images.

METHOD

A retrospective study of all long lines inserted on the neonatal unit over a period of one year was performed. Forty five lines were inserted in 30 neonates over this time. Assessment of the CR images was made by three independent observers by reviewing the films on the viewing console and as hard copy printed films.

RESULTS

Accurate identification of the line tip could be made in 66.7% of cases (kappa = 0.9) using hard copy images and 95.6% cases (kappa = 1.0) using soft copy reporting (significant difference: p = 0.002). The difference in percentage visibility using the two techniques was 28.9% (95% confidence interval 10.2% to 36.7%).

CONCLUSION

The use of soft copy review of CR image improves the visibility of the line tip position compared with hard copy films and reduces the need for repeat radiographs with/without intravenous contrast.

Current practice regarding the enteral feeding of high-risk newborns with umbilical catheters in situ

OBJECTIVE

Textbooks recognize the controversy of concomitant enteral nutrition (EN) during umbilical catheter usage in high-risk newborns, but support for the practice varies. There is only one clinical trial examining these practices in a small but randomized, controlled trial of enterally fed newborns with umbilical arterial catheters (UACs) in situ, and that trial did not demonstrate any adverse consequences. We speculate that concomitant EN with umbilical catheter usage is more common than some textbooks suggest-practiced by at least 20% of all US neonatal intensive care units (NICUs). The objective of this study is to determine the prevalence of NICUs where high-risk newborns with UAC or umbilical venous catheter (UVC) placement receive concomitant EN.

METHODS

Medical Directors listed in the American Academy of Pediatrics United States Neonatologist and Perinatologist Directory were surveyed by mail. On return of surveys, responses to multiple choice questions were recorded by electronic scanning and validated by manually conducted quality control checks. NICU identities were recorded by code to maintain anonymity.

RESULTS

Following 2 requests for survey participation, 70% (549/785) of surveys were returned. Respectively, 82% and 62% of NICUs with and without training programs were represented. On average, surveyed medical directors had practiced neonatal medicine 18.1 +/- 0.3 years. Of surveyed NICUs, 99% reported placement of UVCs and UACs. Of the 92% believing that it is safe to provide trophic EN to newborns with UVCs in place, 51% practiced this some of the time, and 37% practiced it most of the time. By comparison, it was reported that newborns with UACs in place receive trophic EN most of the time (30%), some of the time (49%), or none of the time (22%). Of the 80% believing that it is safe to provide more complete EN to newborns with UVCs in place, 44% practiced this some of the time, and 24% practiced it most of the time. For newborns with UACs in place, more complete EN was provided most of the time (15%), some of the time (36%), or none of the time (49%).

CONCLUSIONS

Concurrent UVC and UAC usage with EN is more commonly practiced than suggested in textbooks or published articles. The relative risk-benefit profiles of these practices remain uncertain secondary to the limited number of controlled clinical observations and to the infrequent occurrence of adverse events. A prospective, multicenter, controlled trial would address the continued advisability of these unexpectedly common practices.

Extravasation of hyperalimentation into the liver parenchyma from a peripherally inserted central catheter

A neonate receiving hyperalimentation through a peripherally inserted central catheter (PICC) had acute abdominal distension and respiratory distress. She was found to have extravasated a 9-cm x 9-cm pocket of hyperalimentation into the liver parenchyma, most likely caused by arterial placement of the PICC. She had severe anasarca and markedly decreased synthetic liver function. After 3 weeks of intensive care, she began to diurese. Her respiratory status subsequently improved, she started feeding, and her liver function test results returned to normal. This case shows the remarkable regenerative capacity of the neonatal liver and provides a rationale for conservative management of this rare but morbid PICC complication.