Hypothermia during umbilical catheterization in preterm infants.

Objective: To describe the effect of umbilical catheterization (UC) on skin temperature and cardiorespiratory status in preterm infants.Materials and methods: In a prospective observational study of infants <32 weeks of gestation, the duration of UC, course of skin temperature, and cardiorespiratory status were registered. Hypothermia was defined as a temperature below 36.5 °C.Results: UC was performed in 55 infants with a median (range) gestational age of 28 weeks (24-31) and birth weight of 1120 g (625-2091). Mean (SD) temperature first decreased 0.6 (0.6)°C during UC followed by a rise of 0.4 (0.4)°C after reaching the minimal temperature. Hypothermia already existed in 69% (38/55) of the infants before start of UC, which increased to 89% (49/55) during UC (p = .001). Duration of UC was not associated with the development of hypothermia during the procedure (p = .48). Heart rate (mean(SD)) significantly increased (162 (17) versus 152 (15); p <.001) and there was a trend toward an increase in supplemental oxygen (mean(SD)) (0.31 (0.17) versus 0.28 (0.13); p = .78), but both changes were only temporary.Conclusion: Hypothermia was frequent in preterm infants before start of UC and increased during UC. Postponing UC until the infant has a normal temperature should be considered.

Thrombosis after umbilical venous catheterisation: prospective study with serial ultrasound.

BACKGROUND: Umbilical venous catheters (UVCs) are associated with thrombus formation. Most studies on thrombosis in infants with UVCs focus on only one part of the route, and none assessed a control group of infants without UVCs. OBJECTIVE: To determine the incidence and location of thrombi in infants after umbilical catheterisation and compare this with a control group of infants without umbilical catheters. DESIGN: Prospective observational study with serial ultrasonography of the UVC route from the umbilico-portal confluence to the heart. Ultrasonography was performed until day 14 after catheterisation in cases and day 14 after birth in controls. RESULTS: Thrombi in the UVC route were detected in 75% (30/40) of infants with UVCs in the study group, whereas no thrombi were detected in the control group of infants without UVCs (0/20) (p<0.001). Six thrombi (20%) were located in the right atrium. Most of these were also partly present in the ductus venosus. Six thrombi (20%) were located in the ductus venosus only, and in 12 infants (40%), the thrombus was at least partly located in the umbilico-portal confluence. Thrombi persisted after UVC removal in 25/30 cases. Two infants with thrombotic events were treated with low-molecular-weight heparin and resolution was found. In the other 23 infants managed expectantly, 2 died due to necrotising enterocolitis, 1 was lost to follow-up and in 20 spontaneous regression was seen. CONCLUSIONS: Thrombotic events occur frequently in infants after umbilical catheterisation. Most thrombi were asymptomatic and regressed spontaneously with expectant management. Routine screening for thrombi in UVCs is therefore not advised.

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.

Femoral Vein Catheter is an Important Risk Factor for Catheter-related Thrombosis in (Near-)term Neonates.

Central venous catheters (CVCs) in neonates are associated with an increased risk of thrombosis. Most reports focus on umbilical venous catheters (UVCs) and peripherally inserted central catheters (PICCs), whereas data available on femoral venous catheters (FVCs) are limited. We performed a retrospective cohort study in all neonates (gestational age ≥34 wk) with CVCs. The primary outcome was the occurrence of thrombosis in CVCs. The secondary outcomes were possible risk factors for thrombosis, the thrombotic incidence in FVCs, UVCs, and PICCs, and clinical aspects of thrombosis in these groups. A total of 552 neonates received a total of 656 catheters, including 407 (62%) UVCs, 185 (28%) PICCs, and 64 (10%) FVCs. Thrombosis was detected in 14 cases, yielding an overall incidence of 2.1% or 3.6 events per 1000 catheter days. FVC was significantly associated with the occurrence of thrombosis when compared with UVC (P=0.02; odds ratio, 3.8; 95% confidence interval, 1.2-12.0) and PICC (P=0.01; odds ratio, 8.2; 95% confidence interval, 1.6-41.7). The incidence of thrombosis was higher in FVCs than in UVCs and PICCS, that is, 7.8% (5/64), 1.7% (7/407), and 1.1% (2/185), respectively (P<0.01). The number of thrombotic events per 1000 catheter days was 12.3 in FVCs, 3.2 in UVCs, and 1.5 in PICCs (P<0.05). We concluded that thrombosis occurs more frequently in FVCs than in other CVCs.

Bloodstream Infection Incidence of Different Central Venous Catheters in Neonates: A Descriptive Cohort Study.

Central venous catheters (CVCs) in neonates are associated with a risk of central line-associated bloodstream infections (CLABSI). Most reports on the incidence of CLABSI in neonates focus on umbilical venous catheters (UVCs) and peripherally inserted central catheters (PICCs). We evaluated the incidence and risk factors for CLABSI in a cohort of neonates with femoral venous catheters (FVCs), UVCs, and PICCs, with a gestational age ≥34 weeks born between January 1, 2006 and June 30, 2013. We included 2,986 neonates with a total of 656 catheters. The CLABSI incidence rate varied from 12.3 per 1,000 catheter-days in FVCs to 10.6 per 1,000 catheter-days in UVCs and 5.3 per 1,000 catheter-days in PICCs. In a Kaplan-Meier survival analysis, we did not find a difference in CLABSI risk between the catheter types (p = 0.29). The following factors were independently associated with an increased risk of CLABSI: parenteral nutrition [hazard ratio (HR) 2.60, 95% confidence interval (CI) 1.25-5.41], male gender (HR 2.63, 95% CI 1.17-5.90), and higher birth weight (HR 1.04, 95% CI 1.002-1.09), whereas antibiotic treatment at birth (HR 0.25, 95% CI 0.12-0.52) was associated with a decreased risk. CONCLUSION: In our cohort, we did not find a difference between the CLABSI incidence in FVCs, PICCs, and UVCs. Occurrence of CLABSI is associated with parenteral nutrition, male gender, and higher birth weight. Antibiotic treatment at birth was associated with a decreased risk of CLABSI.

Revised formula to determine the insertion length of umbilical vein catheters.

UNLABELLED: 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.

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.

Measurement of the 'shoulder-umbilical' distance for insertion of umbilical catheters in newborn babies: questionnaire study.

Approximately 40 years ago, Dr. Peter Dunn introduced a simple method to determine the insertion length of umbilical catheters in neonates, by using the 'shoulder-umbilical' (S-U) length. Since then, various studies have reported a high rate of malposition of umbilical catheters. One of the possible reasons is that the method used to determine the S-U length varies among paediatric professionals. We performed a questionnaire study among 101 paediatric professionals in the Netherlands and found that the method used by the participants to measure the S-U length was highly inconsistent. Placement of an umbilical venous catheter in a too deep position may lead to potentially life-threatening complications. Therefore, uniformity in measurement is paramount for clinical and teaching purposes. Paediatric professionals using Dunn's definition to place umbilical catheters should adhere more strictly to the original description of the measurement of the S-U length.