The pediatric population is known to have more difficult venous access than adults and they often require central venous access for several reasons (Kammoun et al, 2022). In low- and middle-income countries (LMICs), the management of pediatric venous access can have multiple insufficiencies, such as the unavailability of ultrasound and the lack of experienced physicians and skilled nurses, which can make central venous catheter (CVC) placement more difficult and require several attempts (Jarraya et al, 2023).
In our setting, infraclavicular subclavian CVC is commonly used among infants and young children using the landmark technique and a high rate of complications, particularly central line-associated blood stream infections (CLABSIs), was previously reported despite the implementation of a quality management system (Zouari et al, 2018; Jarraya et al, 2023; Kammoun et al, 2023).
The difficulty of the CVC placement may lead to an increased number of attempts or punctures, which can be a risk factor for catheter-related morbidity, as it can increase the duration of the procedure, the risk of arterial puncture, hematoma (Jarraya et all, 2014), and the risk of mistakes (van den Bosch et al, 2022; Tsotsolis et al, 2015). Being aware of the difficulty of pediatric CVC placement is mandatory, as it allows taking precautions. Nevertheless, this difficulty depends on the experience of each team, the patients, and the conditions or habits in every institution, and seems to be widely variable between different settings (Jarraya et al, 2023). The difficulty of CVC placement and its impact on catheter-related morbidity in our pediatric population and in our conditions as a middle income country are not yet well known. So, we conducted this observational study to investigate the main risk factors of a failed first attempt at pediatric CVC placement and the impact of a single-attempt placement in reducing CVC-related morbidity.
Materials and methods
This prospective observational study was conducted after obtaining local ethics committee approval (IRB: HCUH 012/2021) and parents' informed consent. We collected data from infants and young children referred to the pediatric surgery department of our university hospital for percutaneous infraclavicular subclavian vein catheterization under general anesthesia, in the period lasting from November 2021 to December 2023, with regular follow-up visits until one month after.
In this study, we included all pediatric patients aged 3 months to 5 years admitted to the pediatric surgery department for infraclavicular subclavian CVC placement. We included medical, surgical, critically ill, hematology, and oncology patients. We did not include patients with contraindications for CVC placement, such as subclavian vein thrombosis, fracture of the clavicle, or local infection at the insertion site. Neonates and patients whose parents did not consent to participate in the study were not included. We excluded cases of placement failure.
The variables included demographic parameters (age, age <1 year, weight, weight <10kg, comorbidities, American Society of Anesthesiologists (ASA) class, past history of central venous access, context, and indications for catheter placement). The main indications were difficult venous access or inability to obtain peripheral venous access, parenteral nutrition, major surgery requiring prolonged infusion, and chemotherapy. We assessed the difficulty of catheter insertion by assessing the duration of the insertion procedure, the number of attempts, and the occurrence of an accidental arterial puncture. A catheter placement was considered difficult when the physician needed more than two attempts to insert the catheter. To assess catheter-related complications, the site was inspected and the nurses' report was reviewed daily. The complications assessed were infection or CLABSI (Timsit et al, 2020), bleeding or hematoma, pneumothorax, vein thrombosis or vein damage, nerve damage, air embolism, and mechanical complications like dislodgement and malposition. The duration of a catheter was defined as the length of the period between the placement and the removal. Early removal was considered when the duration of the catheter was less than 10 days because it was no longer needed or because of the occurrence of a complication.
All patients had the same protocol of subclavian CVC placement. All catheters were placed in the pediatric surgery operating room with the patient under anesthesia (general anesthesia with intubation, sevoflurane inhalatory sedation with facial mask, supraglottic airway device ventilation, or local anesthesia) by the same team of experienced anesthetists (more than five years of experience in the field of pediatric anesthesia), using the anatomic landmark technique for infraclavicular subclavian vein catheterization. The maintenance of the subclavian CVCs was managed by experienced nurses according to a standardized protocol. In the event of the failure of the procedure, an interval jugular Broviac catheter was a useful alternative, particularly among young infants (<1 year old). A brachial peripherally inserted central catheter (PICC) line may also be used as an alternative, but it is not always available in our settings. Patients with severe thrombocytopenia <20×109/L (children with cancer), received a prophylactic platelet transfusion two hours prior to CVC placement, when peripheral venous access was available. The catheter can be removed with the patient in the supine position by experienced nurses after the doctor's approval. Then, to investigate risk factors of CVC placement difficulties, patients were divided into two groups according to the incidence of failed first attempts at CVC placement:
The sample size was calculated to be 146 patients, considering the incidence of failed first attempts at pediatric CVC placement was 22% in a previous study in the literature (Schiefer et al, 2021) versus 50 % in the preliminary results from the data of the first 50 patients included in this study. This study sample size was required for 95% confidence level and 5% margin of error.
All statistical analyses were achieved using the SPSS 25.0 (SPSS, Chicago, IL, USA) statistical package. The comparison between the two groups was achieved by the Student's t-test for continuous variables and the chi square test for categorical variables. The Fisher exact test was used when the chi square test was not applicable. Logistic regression was used to investigate the risk factors for failed first attempt at pediatric CVC placement and to investigate the impact of single-attempt placement on catheter-related morbidity. Odds ratios (ORs) along with their 95% confidence intervals (CI) are provided. Differences of P<0.05 were considered to be statistically significant.
Results
In this study, 156 infants and young children were admitted for percutaneous subclavian CVC insertion. Six patients were excluded for insertion failure; 150 patients were included. The success rate of pediatric subclavian CVCs' placement using the landmark technique was 96.1%. The incidence of failed first attempts was 41.3%, resulting in 62 patients being enrolled in Group 2 and 88 patients enrolled in Group 1.
Demographic parameters concerning age, weight, the past history of central line placement, and the emergency context were comparable in both groups (Table 1). However, patients with comorbidities, ASA III-IV class, children with cancer, or aplastic anemia were more frequent in Group 2 (Table 1).
| Group 1 Single attempt N=88 | Group 2 Failed first attempt N=62 | P valu | |
|---|---|---|---|
| Age (years) | 3.25 ± 3.8 | 3.88 ± 3.9 | 0.330 |
| Age <2 years (infants) | 24 (27.2%) | 22 (35.4%) | 0.185 |
| Age: 2–5 years (young children) | 64 (72.7%) | 40 (64%) | 0.215 |
| Weight (kg) | 15.9 ±11 | 16.6 ±11 | 0.738 |
| Weight <10 kg | 28 | 26 | 0.135 |
| With comorbidities | 66 | 56 | 0.014 |
| ASA Class (I–II/III–IV) | 62/26 | 38/24 | 0.046 |
| History of central venous catheterization | 42 | 26 | 0.297 |
| Emergency | 20 | 14 | 0.573 |
| Medical and surgical pediatric patients | 46 | 2 | 0.0001 |
| Critically-ill patients (from ICU) | 18 | 18 | 0.478 |
| Hematology and oncology patients | 24 | 42 | 0.0001 |
| Subclavian CVC indications: | |||
| Difficult venous access | 56 | 28 | 0.021 |
| Parenteral nutrition | 4 | 0 | – |
| Perioperative | 8 | 2 | 0.332 |
| Oncology | 20 | 32 | 0.001 |
ASA=American Society of Anesthesiologists; CVC=central venous catheterization; ICU=intensive care unit
The failed first attempt prolonged the duration of the procedure from 12.3±3min in Group 1 to 18.1±4 min in Group 2 and was more frequent among sedated patients (Table 2). Catheter placement was difficult (more than two attempts) among 23 patients (37.1%) of Group 2.
| Group 1 Single attempt N=88 | Group 2 Failed first attempt N=62 | P value | |
|---|---|---|---|
| Duration of the procedure (minutes) | 12.3±3 | 18.1±4 | 0.0001 |
| Number of attempts | 1 | 2.45±0.6 | 0.0001 |
| Difficult catheter placement (more than two attempts) | 0 | 23 | <0.0001 |
| Without peripheral venous access | 28 | 25 | 0.079 |
| Anemia | 40 | 28 | 0.992 |
| Thrombocytopenia <50000 | 14 | 22 | 0.019 |
| Anesthesia technique: | |||
| General anesthesia with intubation | 18 | 4 | 0.036 |
| Sedation with facial mask | 67 | 50 | 0.438 |
| Sedation with I-Gel | 1 | 6 | 0.004 |
| Awake with local anesthesia | 2 | 2 |
The main risk factors for a failed first attempt at CVC placement among infants and young children were children with previous comorbidities (OR=3.11; 95%CI: 1.17–8.21), hematology and oncology patients (OR=5.6; 95%CI: 2.75–11.38), and children with aplastic anemia (OR=3.05; 95%CI:1.388–6.705). Furthermore, the anesthesia sedation with supraglottic airway device (I-Gel) ventilation increased the risk of a failed first attempt with OR=9.21; 95%CI: 1.080–78.5. However, tracheal intubation may protect against this risk with OR=0.28; 95%CI: 0.091–0.891.
In our study, the incidence of complications, particularly CLABSI, was lower in the single-attempt group. Moreover, a single-attempt catheter placement was a protective factor against catheter-related complications with OR=0.258 [0.12–0.55] and against CLABSI with OR=0.132[0.054–0.32]. On the other hand, we did not find any correlation with the other complications (Table 3).
| Group 1 Single attempt N=88 | Group 2 Failed first attempt N=62 | P value | OR [95%CI] (Single attempt) | |
|---|---|---|---|---|
| Complicated | 16 (18.1%) | 34 (54.8%) | ≤0.0001 | OR=0.258 [0.12–0.55] |
| CLABSI | 8 (9.1%) | 26 (42%) | ≤0.0001 | OR=0.132 [0.054–0.32] |
| Bleeding and/or hematoma | 4 (4.5%) | 12 (19.3%) | 0.004 | OR=0.45 [0.121–1.67] |
| Mechanical complications | 6 (6.8%) | 0 | 0.038 | |
| Thrombosis | 2 (2.2%) | 4 (6.4%) | 0.222 | |
| Pneumothorax | 0 | 0 | ||
| Duration of the CVC (days) | 10.7±6.7 | 12.3±8 | 0.180 | |
| Early removal | 42 | 26 | 0.297 | |
| Removed when not needed | 74 | 32 | ≤0.0001 |
CLABSI=central line-associated bloodstream infection; CVC=central venous catheter
Discussion
This study reports the risk of difficult pediatric subclavian CVC and the interest of a single-attempt placement according to our experience in the management of pediatric central lines using infraclavicular subclavian vein catheterization with the anatomic landmark approach.
In infants and young children, the subclavian route is easier because the diameter of the subclavian vein is wider than that of the internal jugular one. Moreover, internal jugular access is not practical for infants with short necks and generally requires an ultrasound approach, which is not available in our department. As stated above, the main risk factors for difficult CVC in our population were children with comorbidities, hematology and oncology patients, children with aplastic anemia, and anesthesia sedation with I-Gel airway ventilation. Also, single-attempt catheterization protects against catheter-related complications. These results have several clinical implications, allow us to take particular precautions with strenuous aseptic measures, and invite us to change our anesthesia technique and practice during CVC placement.
We experienced high rates of success (96%) but also a high incidence of failed first attempts during CVC placement (41%). This may be explained by including infants aged less than 6 months in this study. In the literature, the success rate of subclavian CVC placement has been reported up to 78.8% in infants younger than 6 months, and up to 96% in pediatrics older than 6 months (Aminnejad et al, 2015). However, measuring the difficulty of pediatric CVC placement by considering a failed first attempt is not common in the literature. We think that the difficulty of the procedure depends on the experience and skills of the team of healthcare providers, which may vary from one department to another (Timsit, 2003), and on patients' characteristics, because multiple repeated accesses and catheter-related complications may lead to difficulty in reestablishing a central line (Chaochankit and Sangkhathat, 2019). This may explain our results, because children with comorbidities and hematology and oncology patients, particularly those who suffer from aplastic anemia, previously have had several central lines and received veinotoxic treatments, such as chemotherapy, which can affect the quality of the endothelium and make the catheterization procedure more difficult and dangerous (Armenteros-Yeguas et al, 2017). For example, the anticancer drug administration induces unhealthy subcutaneous tissue (thrombus or edema) without subjective symptoms, which may increase the risk of difficult catheterization as well as complications (Abe-Doi et al, 2020). Nevertheless, previous studies showed that the history of vascular access complications is a risk factor for difficult CVC placement (Armenteros-Yeguas et al, 2017; Grant et al, 2021).
However, in our study, this factor was not proven. This may be due to the population included in our study whose age was under 5 years and may be because of our strategy in managing central venous access in children by changing the site of CVC placement every time a child requires a CVC (changing from right to left side or from a supraclavicular to an infraclavicular site (Lu et al, 2006)). In our study, the quasi-totality of children had CVC under anesthesia. We found that deep sedation with supraglottic airway (I-Gel) ventilation increased the difficulty of the subclavian CVC placement in comparison with facial mask ventilation or general anesthesia with intubation. This finding is original and was not reported previously; it invites us to change our anesthesia practice for CVC placement. On the other hand, there was no increased incidence of failed first attempts among sedated patients with facial mask ventilation. We think that the difficulty was not caused by the depth of anesthesia. We think that the I-Gel may change the anatomical landmarks of the cervical region, which may disturb the operator using the landmark technique (Ahuja et al, 2023; Jarraya et al, 2023). On the other hand, it was reported that reduced procedural time and fewer venipuncture attempts and arterial pricks may protect against early and late catheter-related morbidity (Ahmed et al, 2023). So, to improve our CVC-related outcomes, we suggest the use of an ultrasound (US) approach, based on the data from metanalyses showing the superiority of the real-time US-guided CVC technique over the landmark method by reducing the time of cannulation (De Souza et al, 2018), the success rate (Lau and Chamberlain, 2016), the number of attempts (Froehlich et al, 2009), and improving the CVC-related outcomes (Dassinger et al, 2015). This technique is still unavailable in our department as in many other low- and middle-income countries (Hanauer et al, 2020).
Limitations
The main limitation of our study is that it was a monocentre observational study, and these results are particular to our setting and to our central line management protocols. Moreover, this study included a heterogeneous sample as it included infants and young children, which can present a bias because they don't have the same difficulty with CVC placement or the same outcomes.
Conclusion
In this study, we showed that, according to our experience in pediatric central lines, the main risk factors for a difficult pediatric subclavian CVC were children with comorbidities, hematology and oncology patients, children with aplastic anemia, and anesthesia sedation with I-Gel airway ventilation. On the other hand, the difficulty of placement seems to increase catheter-related morbidity, and a single-attempt catheter placement seems to be a protective factor. In clinical practice, awareness of the main risk factors of failed attempts is mandatory and allows for the taking of necessary precautions and, sometimes, the changing of some habits to guide further improvement actions.