Catheter-related deep vein thrombosis: Where are we at and where are we going? Updates and ongoing unmet clinical needs

BACKGROUND

Catheter-related thrombosis (CRT) is one of the major complications affecting patients with indwelling venous catheters, usually involving the upper extremity deep venous system. This condition can lead to potentially life-threatening complications such as pulmonary embolism and sepsis. The risk of developing CRT varies depending on type of catheters and patient characteristics. Despite advances in materials and technologies, the actual incidence of CRT is still considerable. Available evidence on CRT management remains controversial, and clinical guidelines base their recommendations on data from non-catheter related upper extremity or lower extremity deep venous thromboses.

AIMS

This narrative review aims to describe the epidemiology of CRT, to review the available evidence on its management and to highlight the current unmet needs.

METHODS

No formal search strategy was applied for the revision of the literature. The main sources of information used were Medline and guidelines from international societies.

CONTENT

The management of CRT requires a careful balance between the risk of thrombus progression, recurrent events, and systemic embolization and the increased bleeding risk in often fragile patients. Open issues include the optimal management of the catheter and the type and duration of anticoagulant therapy. Direct oral anticoagulants are increasingly prescribed, representing an important alternative to the standard of care low molecular weight heparins in selected cases. The development of new anticoagulant drugs such as factors XI and XII inhibitors may offer further advantages in this context.

CONCLUSIONS

The management of CRT is still challenging with constant need for updated evidence to support tailored approaches.

Effects of Peripherally inserted Central Catheter (PICC) materials and designs on reduction of PICC-related complications: A systematic review and meta-analysis

Studies showed that integrating coating or valve into Peripherally Inserted Central (PICC) can prevent related complications. However, data regarding efficiency were controversial. Therefore, a systematic review was needed to analyse the effect of PICC materials and designs on reduction of PICC-related complications. We searched PubMed, Cochrane library, EMbase, grey literature and referent literature from inception to 5 August 2022. Randomized controlled trials (RCTs) and case-control study were included. Two authors extracted data independently, using a predesigned Excel form, and assessed the quality of included RCTs according to the Cochrane Handbook for Systematic Reviews (V5.1.0), case-control study was assessed by the Newcastle-Ottawa Scale. Data were analysed using Review Manager (v5.3.0). A total of 10 RCTs and one case-control study were included. Meta-analysis results showed that PICC designs reduce the incidence of obstruction, and at the critical value of PICC-associated bloodstream infection, but may have no effects on other complications. Based on the literature reviewed, we can only say PICC new materials did not reflect significant reduction on complications, what's more, the result needs more multicentre, large RCTs to support. We suggested clinicians combine descriptive research and cost-effect analysis to select appropriate PICC materials and designs for patients.

Clinical experience with a chlorhexidine-coated PICC: A prospective, multicenter, observational study

INTRODUCTION

This study evaluated a chlorhexidine-coated peripherally inserted central catheter (PICC) and the incidence of associated complications within both inpatient and outpatient populations.

METHODS

This IRB-approved, multicenter, prospective observational study was performed at three large teaching hospitals in the US. All adults who required a PICC for ⩾14 days were considered. Patients were monitored throughout entire catheter dwell. Duplex venous ultrasounds were performed before insertion, after 10 to 14 days of dwell time, and upon removal. Data was collected from the hospital, outpatient clinic, and patient PICC diary records.

RESULTS

A total of 103 patients, 56% male, with mean BMI 29 ± 8.8, were enrolled. The majority (79%) of patients were from high-risk groups-cancer, infectious diseases, transplant, and trauma. Primary treatment indications were antibiotics (66.99%) and chemotherapy (25.24%). Double lumen PICCs (59.2%) were favored clinically, as was basilic vein placement (71.84%). Mean catheter dwell was 47.01 ± 25.82 days. Three (3, 2.9%) central line-associated bloodstream infections (CLABSI) were reported. Four patients (4.6%) reported symptomatic catheter-related thrombosis (CRT), confirmed with ultrasound. Three patients (3.4%) had ultrasound-confirmed fibroblastic sleeve (FS). Eight patients (9.2%) who entered the study with pre-existing superficial thrombosis, had complete resolution at the time of catheter removal. The incidence of CLABSI was 0.82/1000 days. The combined CRT and FS rate was 6.9%.

CONCLUSION

Based upon the observational findings of this study, chlorhexidine-coated PICC technology may be considered for use in patient populations who are at moderate to high-risk for catheter-related complications in both inpatient and outpatient settings.

Incidence and Risk Factors for Superficial and Deep Vein Thrombosis in Post-Craniotomy/Craniectomy Neurosurgical Patients

Background Venous thromboembolism (VTE) is quite common among post-operative neurosurgical patients. This study aims to identify the incidence of deep vein thrombosis (DVT) and superficial vein thrombosis (SVT) among post-craniotomy/craniectomy patients and further evaluate established hypercoagulability risk factors such as trauma, tumors, and surgery. Methodology This single-center retrospective study investigated 197 patients who underwent a craniotomy/craniectomy. The incidences of DVT and SVT were compared, along with laterality and peripherally inserted central catheter (PICC) line involvement. A multivariate logistic regression analysis was conducted to identify risk factors for post-craniotomy/craniectomy VTE. This model included variables such as age, post-operative days before anticoagulant administration, female sex, indications for surgery such as tumor and trauma, presence of a PICC line, and anticoagulant administration. Results Among the 197 post-craniotomy/craniectomy patients (39.6% female; mean age 53.8±15.7 years), the incidences of DVT, SVT, and VTE were 4.6%, 9.6%, and 12.2%, respectively. The multivariate logistic regression analysis found that increasing the number of days between surgery and administration of anticoagulants significantly increased the risk of VTE incidence (odds ratio 1.183, 95% CI 1.068-1.311, p = 0.001). Conclusions Contrary to existing evidence, this study did not find trauma or the presence of tumors to be risk factors for VTE. Future prospective studies should assess VTE risk assessment models such as "3 Bucket" or "Caprini" to develop universal guidelines for administering anticoagulant therapy to post-craniotomy/craniectomy patients that consider the timing of post-operative therapy initiation.

Upper Extremity Deep Venous Thrombosis: Etiologies, Diagnosis, and Updates in Therapeutic Strategies

Upper extremity deep vein thrombosis (UEDVT) is responsible for 4 to 10% of all deep vein thrombosis (DVT). Untreated UEDVT can lead to significant disability secondary to the postthrombotic syndrome. To date, there are no randomized trials specifically comparing different therapeutic strategies. Ultimately, optimal management of UEDVT depends on the underlying etiology, patient symptoms, and degree of thrombosis, with supporting evidence primarily extrapolated from lower extremity DVT data. This article will review the classification, presentation, and diagnosis of both primary and secondary UEDVT. In addition, it will discuss updates in clinical guidelines, anticoagulation, endovascular and surgical treatment strategies.

The incidence and risk of venous thromboembolism associated with peripherally inserted central venous catheters in hospitalized patients: A systematic review and meta-analysis

Background

Venous thromboembolism (VTE) can be fatal if not treated promptly, and individual studies have reported wide variability in rates of VTE associated with peripherally inserted central catheters (PICC). We thus conducted this meta-analysis to investigate the overall incidence and risk of developing PICC-related VTE in hospitalized patients.

Methods

We searched PubMed, Embase, Scopus, and Web of Science databases from inception until January 26, 2022. In studies with a non-comparison arm, the pooled incidence of PICC-related VTE was calculated. The pooled odds ratio (OR) was calculated to assess the risk of VTE in the studies that compared PICC to the central venous catheter (CVC). The Newcastle-Ottawa Scale was used to assess methodological quality.

Results

A total of 75 articles (58 without a comparison arm and 17 with), including 109292 patients, were included in the meta-analysis. The overall pooled incidence of symptomatic VTE was 3.7% (95% CI: 3.1–4.4) in non-comparative studies. In the subgroup meta-analysis, the incidence of VTE was highest in patients who were in a critical care setting (10.6%; 95% CI: 5.0–17.7). Meta-analysis of comparative studies revealed that PICC was associated with a statistically significant increase in the odds of VTE events compared with CVC (OR, 2.48; 95% CI, 1.83–3.37; P < 0.01). However, in subgroup analysis stratified by the study design, there was no significant difference in VTE events between the PICC and CVC in randomized controlled trials (OR, 2.28; 95% CI, 0.77–6.74; P = 0.13).

Conclusion

Best practice standards such as PICC tip verification and VTE prophylaxis can help reduce the incidence and risk of PICC-related VTE. The risk-benefit of inserting PICC should be carefully weighed, especially in critically ill patients. Cautious interpretation of our results is important owing to substantial heterogeneity among the studies included in this study.

Upper Extremity Deep Vein Thrombosis: Current Knowledge and Future Directions

Upper extremity deep vein thrombosis (UEDVT) has been increasing in incidence due to the escalating use of central venous catheters such as peripherally inserted central catheters. UEDVT can be primary idiopathic or secondary to pacemaker leads, intravascular catheters or cancer. In comparison to conventional venous thromboembolism such as lower limb deep vein thrombosis or pulmonary embolism the risk factors, investigations, and management are not well defined. We review current evidence in primary and secondary UEDVT, highlighting areas in need of further research. We also explore the entity of venous thoracic outlet syndrome, which is said to be a risk factor for recurrent primary UEDVT and is the rationale behind surgical interventions.

Plasminogen activator inhibitor-1 gene promoter 4G/5G polymorphism and risks of peripherally inserted central catheter-related venous thrombosis in patients with lung cancer: a prospective cohort study

PURPOSE

This study investigated the influence of plasminogen activator inhibitor-1 (PAI-1) gene polymorphisms and other contributing clinical factors on peripherally inserted central catheter-related venous thrombosis (PICC-RVT) in Chinese patients with lung cancer.

METHODS

We conducted a prospective study of 237 participants. Blood samples were collected to detect the PAI-1 4G/5G genotype. Venous thromboembolism risk was calculated by the Caprini risk assessment model. Color Doppler ultrasonography was performed every 7 days for 3 weeks to confirm PICC-RVT.

RESULTS

The rate of PICC-RVT was 13.50% (32/237). The 5G/5G, 4G/5G, and 4G/4G genotypes were found in 12.50% vs 17.56%, 59.38% vs 49.27%, and 28.12% vs 34.17% in the thrombus group and the non-thrombus group of the participants. No difference was observed in the distribution frequency of the three genotypes between the thrombus and non-thrombus groups. A higher fibrinogen level (OR 1.194, 95% CI 1.004-1.420, P = 0.045) and a higher Caprini score (OR 1.698, 95% CI 1.103-2.614, P = 0.016) were statistically significant risk factors for PICC-RVT. Compared with patients who underwent a pemetrexed/cisplatin regimen, those who were administered paclitaxel/cisplatin (OR 18.332, 95% CI 2.890-116.278, P = 0.002) or gemcitabine/cisplatin (OR 6.617, 95% CI 1.210-36.180, P = 0.029) were at increased risk of PICC-RVT.

CONCLUSION

Our finding suggested that there is no statistically significant influence of the PAI-1 4G/5G gene variant on PICC-RVT in Chinese patients with lung cancer. However, patients with higher Caprini scores and higher fibrinogen levels are at increased risk for PICC-RVT, as are patients receiving chemotherapy. Clinical staff should carefully perform a risk assessment for patients with PICC. Those with the above risk factors should pay close attention and take timely and effective preventive measures.

Peripherally inserted central venous catheter in upper extremities leads to an increase in D-dimer and deep vein thrombosis in lower extremities

Background

The purpose of this study is to elucidate the association between peripherally inserted central venous catheter (PICC) in upper extremities and lower extremity deep venous thrombosis (LEDVT) by observing the changes in D-dimer.

Methods

This was a retrospective cohort study with 3452 patients (104 inserted with PICCs and 3348 without PICC) enrolled at the neurology department from April 1, 2017 to April 1, 2020. The patients underwent color Doppler ultrasound (CDU) and D-dimer examinations. LEDVT-related factors and D-dimer value were analyzed before and after PICC insertion. The predictive value of D-dimer for LEDVT was also evaluated.

Results

Univariate logistic regression analysis showed that PICC insertion increased the risk of LEDVT by 9 times and promoted the increase of D-dimer by 5 times. After risk adjustment, multivariate logistic regression analysis showed that PICC insertion increased the risk of LEDVT by 4 times and tripled the risk of D-dimer increase. The concentration of D-dimer was significantly increased after PICC insertion. D-dimer was unsuitable for excluding venous thrombosis in patients inserted with PICCs.

Conclusions

PICC insertion increases the level of D-dimer and the risk of LEDVT. The risks of venous thrombosis need to be assessed in patients inserted with PICCs to ensure the expected clinical outcomes.

Assessing the thrombosis risk of peripherally inserted central catheters in cancer patients using Caprini risk assessment model: a prospective cohort study

PURPOSE

There was no optimal risk assessment tool to stratify the risk of peripherally inserted central catheter-related venous thromboembolism (PICC-RVT) in cancer patients. We currently use the Caprini risk assessment model for thrombotic risk assessment, but no evidence exists on the effectiveness of Caprini in such patients. This study was to assess the validity of the Caprini in Chinese cancer patients with PICCs.

METHODS

We conducted a prospective study of 468 participants. Following calculating the Caprini score, color Doppler ultrasonography was performed every 7 days for 3 weeks to confirm PICC-RVT.

RESULTS

There was a correlation between PICC-RVT and the Caprini score. Compared with scores of 5, the risk was 2.089-fold greater (95% CI 1.165-3.743, P = 0.012) in patients with a score of 6 and 7, and 7.156-fold greater (95% CI 3.157-16.217, P < 0.001) in patients with scores ≥8. The area under the receiver-operating characteristic curve was 0.636 (95% CI 0.590-0.680; P < 0.001). 6 was the best cutoff point for Caprini, with a sensitivity of 0.76 and a specificity of 0.44.

CONCLUSIONS

The Caprini can be used for high-risk screening of the PICC-RVT in cancer patients, and classification of the highest risk level using a score of 6 can be more clinically significant compared to 5 as recommended. The results provide evidence for the practitioner's early use of the Caprini to assess the thrombotic risk in patients with PICCs and take timely prevention measures. But pharmacological prevention should be considered seriously for its low specificity.

The Caprini thrombosis risk model predicts the risk of peripherally inserted central catheter-related upper extremity venous thrombosis in patients with cancer

BACKGROUND

A peripherally inserted central catheter (PICC) is often necessary for patients receiving chemotherapy, but there is a risk of PICC-related venous thrombosis (VT). We sought to use the Caprini thrombosis risk model and color Doppler flow imaging for the dynamic monitoring of an eventual thrombosis in patients receiving chemotherapy.

METHODS

This prospective study was carried out from January 2018 to May 2019 in patients who underwent PICC implantation and maintenance at the First Affiliated Hospital of Fujian Medical University. The outcome event was the occurrence of PICC-related upper extremity venous thrombosis confirmed by color Doppler flow imaging.

RESULTS

A total of 201 participants were enrolled, of whom 108 (53.7%) developed VT. Three participants (1.5%) developed symptomatic VT. Univariable logistic regression analysis suggested that the Caprini score (odds ratio [OR], 1.243; 95% confidence interval [CI], 1.074-1.438; P = .003), the PICC model (OR, 0.448; 95% CI, 0.223-0.901; P = .024), and a previous history of PICC-related deep vein thrombosis (OR, 9.388; 95% CI, 1.178-74.786; P = .034) were associated with PICC-related upper extremity VT. Multivariable logistic regression analysis showed that only the Caprini score (OR, 1.188; 95% CI, 1.018-1.386; P = .029) was an independent risk factor for PICC-related venous thrombus. A receiver operating characteristic curve analysis showed the Caprini risk assessment model had a predictive value for upper extremity VT, with an area under the curve of 0.615 (95% CI, 0.538-0.693), 74.1% sensitivity, and 44.1% specificity.

CONCLUSIONS

The Caprini score is an independent predictor of the development of PICC-related VT in patients with cancer. However, the moderate sensitivity and low specificity of the Caprini risk assessment model may limit its predictive value in the clinical setting.

Comparing Incidence of Thrombosis in PICC and Midlines and Evaluating the Role of Anticoagulation, Site of Insertion, and Risk Factors

New practice models are in demand for prevention and reduction in rates of catheter thrombosis that can be devastating to the health care system and patients Risk factors for catheter thrombosis were analyzed retrospectively for their impact Site of insertion and overall use of anticoagulation at the time of catheter placement did not show any significant impact on incidence of thrombosis Several variables (i.e., triple lumen, critically ill) were used to create a clinical prediction score model

Predictive risk factors of venous thromboembolism (VTE) associated with peripherally inserted central catheters (PICC) in ambulant solid cancer patients: retrospective single Centre cohort study

Aims

Peripherally inserted central catheters(PICC) lines are becoming increasingly popular in solid cancer patients for the administration of chemotherapy. This study aims looking at the incidence of PICC line related and distant thromboembolism associated with these catheters and exploring risk factors.

Methods

Records were reviewed for 158 patients who underwent PICC line insertion over the two years period in the medical oncology unit, Milton Keynes University Hospital. The Incidence PICC line related Deep Venous Thrombosis (DVT) which is defined as upper extremity DVT at the site of PICC line insertion was documented after checking reports of ultrasound Doppler of all symptomatic patients to confirm the presence of thrombo-embolism and Computed Tomography(CT)scan or Computed Tomography Pulmonary Angiography (CTPA) to confirm the presence Pulmonary Embolism(PE).

Results

23(13%) symptomatic patients with confirmed diagnosis by ultrasound Doppler were found to have PICC line related DVT and similar number of patients developed distant VTE, namely PE and lower limbs DVT. Average time to thrombo-embolism from the insertion of PICC line was 13 days and 51 days in distant VTE. Statistically significant results have been identified in the term of risk factors leading to VTE events during the period of PICC line insertion.

Conclusions

VTE is a common complication in medical oncology patients who underwent insertion PICC line insertion for chemotherapy. Risk of distant VTE is high as well as the PICC line related DVT and the risk of the PICC line related DVT is higher in the first two weeks after PICC insertion. We concluded that high BMI,high PLTs count and Fluropyrimidine containing chemotherapy are all significant risk factors for VTE events recorded while smoking and high BMI are significantly contributing to the high rate of the PICC line related DVT.

Handgrip exercise reduces peripherally-inserted central catheter-related venous thrombosis in patients with solid cancers: A randomized controlled trial

BACKGROUND

Peripherally-inserted central catheter-related venous thrombosis has serious complications including the loss of vascular access, recurrent venous thrombosis, and post-thrombotic syndrome. Current guidelines recommend non-pharmacological strategies to prevent peripherally-inserted central catheter-related venous thrombosis. There is little evidence for the effectiveness of handgrip exercise on the prevention of peripherally-inserted central catheter-related venous thrombosis.

OBJECTIVES

To examine the effectiveness of handgrip exercise using an elastic ball to prevent peripherally-inserted central catheter-related venous thrombosis in patients with solid cancers.

DESIGN

A randomized controlled trial.

SETTINGS

One teaching hospital in Nanjing, China.

PARTICIPANTS

In total, 120 subjects with solid cancers were eligible; each had a new peripherally-inserted central catheter. They were recruited and randomly assigned into two exercise groups and one control group.

METHODS

Subjects from exercise groups 1 and 2 performed a 3-week, 25-repetition handgrip exercise, 3 and 6 times daily, respectively. The control group subjects performed a gentle limb exercise with no frequency and intensity requirements. Ultrasound was used to detect venous thrombosis development and examine axillary vein blood flow over the three points.

RESULTS

There were 32 cases of peripherally-inserted central catheter-related venous thrombosis detected. Two venous thrombosis cases in the control group were symptomatic, but all venous thrombosis cases in the exercise groups were asymptomatic. All venous thromboses were partial. There were significant differences in the incidence of venous thrombosis among the three groups (χ² = 12.813, p = 0.002; χ² = 9.340, p = 0.009; χ² = 11.480, p = 0.003; and χ² = 10.534, p = 0.005, respectively) at days 2, 3 and 21. The incidence of venous thrombosis in the two exercise groups was lower than that in the control group over the 3 time points (all, p < 0.05). The between-group effects and interaction effect in vein maximum velocity and time-mean flow velocity showed significant differences (F = 4.180, p = 0.025; F = 4.010, p = 0.045; and F = 2.928, p = 0.025) at days 2, 3, and 21, respectively. The axillary vein blood flow parameters in the control group were lower than those in the two exercise groups at day 21 (all, p < 0.05). However, no significant differences occurred in the incidence of venous thrombosis and axillary vein blood flow parameters between the two exercise groups.

CONCLUSION

Handgrip exercise using an elastic ball daily for three weeks could decrease the incidence of peripherally-inserted central catheter-related venous thrombosis. The method is simple, with no negative consequence reported. Further studies are required to confirm this conclusion and to explore the optimal frequency of handgrip exercise.

The incidence and predictors of symptomatic venous thromboembolism associated with peripherally inserted central catheters in patients with nasopharyngeal carcinoma

Background

Despite wide usage, peripherally inserted central catheter (PICC)-related venous thromboembolism (VTE) is common in nasopharyngeal carcinoma (NPC) patients.

Patients and methods

This was a retrospective cohort study of NPC patients with PICC insertions from February 2, 2007 to December 25, 2014 in Sun Yat-Sen University Cancer Centre. Univariable and multivariable logistic regression analyses were used to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for the correlations between risk factors and symptomatic PICC-VTE.

Results

Of the 1,363 NPC patients, 76 developed symptomatic VTE. In univariable analysis, body mass index (BMI), Eastern Cooperative Oncology Group (ECOG) score, metastasis stage (M stage), and VTE history were associated with symptomatic PICC-VTE. Following multivariable adjustments, BMI (OR 0.900, p=0.007), ECOG score (OR 4.162, p=0.011), M stage (OR 2.717, p=0.019), and VTE history (OR 109.772, p<0.001) were still statistically significant.

Conclusion

PICC-VTE is a common complication in NPC patients, with an incidence of 5.6% in our analysis. Those with VTE history and lower BMI and worse ECOG performance score metastatic NPC patients are more susceptible to symptomatic PICC-related thrombosis and thus may require prophylactic anticoagulation.

Is Peripherally Inserted Central Catheter-Related Thrombosis Associated With ABO Blood Group? A Case-Control Pilot Study

Peripherally inserted central catheter (PICC) use is associated with many complications including line-related thrombosis. Several studies and meta-analyses confirmed the increased risk to develop venous thromboembolism in non-O blood group individuals. Our pilot study aimed to examine whether PICC-related thrombosis is influenced by ABO blood group. We identified patients admitted to Hurley Medical Center between March 2012 and March 2016 who had PICC placed during their admission, had their ABO blood group identified in their medical record, and had upper extremity venous Doppler ultrasound performed on the same side of PICC. We excluded pregnant women, patients on anticoagulation initiated before PICC insertion, and patients with active cancer. Data of 227 patients who met our criteria were analyzed. Of these patients, 140 (61.7%) patients had PICC-related thrombosis (cases) and 86 (37.9%) patients had O blood group. Controls were patients who had PICC and did not develop PICC-related thrombosis. Multivariate logistic regression revealed no association between PICC-related thrombosis and ABO blood group (adjusted odds ratio: 1.1; 95% confidence interval: 0.6-2.0; P = .733). Therefore, our data suggest that non-O blood group does not increase the odds of having PICC-related thrombosis.

The mechanistic causes of peripheral intravenous catheter failure based on a parametric computational study

Peripheral intravenous catheters (PIVCs) are the most commonly used invasive medical device, yet up to 50% fail. Many pathways to failure are mechanistic and related to fluid mechanics, thus can be investigated using computational fluid dynamics (CFD). Here we used CFD to investigate typical PIVC parameters (infusion rate, catheter size, insertion angle and tip position) and report the hemodynamic environment (wall shear stress (WSS), blood damage, particle residence time and venous stasis volumes) within the vein and catheter, and show the effect of each PIVC parameter on each hemodynamic measure. Catheter infusion rate has the greatest impact on our measures, with catheter orientation also playing a significant role. In some PIVC configurations WSS was 3254 times higher than the patent vein, and blood damage was 512 times greater, when compared to control conditions. Residence time is geometry-dependent and decreases exponentially with increasing insertion angle. Stasis volume decreased with increasing infusion rate and, to a lesser degree, insertion angle. Even without infusion, the presence of the catheter changes the flow field, causing low velocity recirculation at the catheter tip. This research demonstrates how several controllable factors impact important mechanisms of PIVC failure. These data, the first of their kind, suggest limiting excessive infusion rates in PIVC.

A Randomized Trial of Central Venous Catheter Type and Thrombosis in Critically Ill Neurologic Patients

BACKGROUND

Observational studies suggest peripherally inserted central venous catheters (PICCs) are associated with a high risk of catheter-related large vein thrombosis (CRLVT) in critically ill neurologic patients. We evaluated the difference in thrombosis risk between PICCs and centrally inserted central venous catheters (CICVCs).

METHODS

We conducted a pragmatic, randomized controlled trial of critically ill adult neurologic patients admitted to neurological and trauma critical care units at two level I trauma centers. Patients were randomized to receive either a PICC or CICVC and undergo active surveillance for CRLVT or death within 15 days of catheter placement.

RESULTS

In total, 39 subjects received a PICC and 41 received a CICVC between February 2012 and July 2015. The trial was stopped after enrollment of 80 subjects due to feasibility affected by slow enrollment and funding. In the primary intention-to-treat analysis, 17 (43.6 %) subjects that received a PICC compared to 9 (22.0 %) that received a CICVC experienced the composite of CRLVT or death, with a risk difference of 21.6 % (95 % CI 1.57-41.71 %). Adjusted common odds ratio of CRLVT/death was significantly higher among subjects randomized to receive a PICC (adjusted OR 3.08; 95 % CI 1.1-8.65). The higher adjusted odds ratio was driven by risk of CRLVT, which was higher in those randomized to PICC compared to CICVC (adjusted OR 4.66; 95 % CI 1.3-16.76) due to increased large vein thrombosis without a reduction in proximal deep venous thrombosis.

CONCLUSIONS

Our trial demonstrates that critically ill neurologic patients who require a central venous catheter have significantly lower odds of ultrasound-diagnosed CRLVT with placement of a CICVC as compared to a PICC.

Rivaroxaban in the Treatment of PICC-associated Upper Extremity Venous Thrombosis

PURPOSE

Peripherally inserted central catheters (PICCs) are frequently used for prolonged drug administration, but their use is commonly complicated by the development of upper extremity deep venous thrombosis (UEDVT) requiring anticoagulation. Here, we compared the efficacy and safety profile of rivaroxaban (20 mg/d) with low molecular weight (LMW) heparin and vitamin K antagonists in the treatment of PICC-associated UEDVT.

METHODS

Patients (N = 84) with PICC-associated UEDVT were studied. All had UEDVT identified by ultrasound scanning. Further ultrasound images were obtained at 1, 2, and 3 months after the start of treatment. Forty-four patients were treated with rivaroxaban and 40 with initial LMW heparin and vitamin K antagonist with continuation of vitamin K antagonists alone once international normalized ratio was therapeutic FINDINGS: In the rivaroxaban group mean (SD) age was 51 (16) years and 57% were men, whereas in the other group respective values were 50 (16) years and 56%. All patients were receiving treatment for cancer. Resolution of thrombus had occurred in 53.5% at 1 month, 76.1% at 2 months, and 92.6% at 3 months in the rivaroxaban-treated patients. Corresponding values in the LMW heparin/vitamin antagonist-treated patients were 34.2%, 55.5%, and 88.5%, respectively. Differences between groups were significant at 1 month (P < 0.01) and 2 months (P < 0.05). There were no major bleeds in either group, and cumulative bleeding rates by 3 months were 7.3% in the rivaroxaban group and 11.4% in the LMW heparin/vitamin K antagonist group.

IMPLICATIONS

Rivaroxaban led to faster resolution of PICC-associated UEDVT than LMW/vitamin K antagonists without any increase in bleeding.

The natural history and outcomes of line-associated upper extremity deep venous thromboses in critically ill patients

OBJECTIVE

Anticoagulation remains the standard of care for line-associated upper extremity deep venous thrombosis (UEDVT). This treatment carries the risk of hemorrhagic complications, possibly more so in surgical patients. Considering the low-risk profile of UEDVT-which is associated with fewer, less severe pulmonary emboli than lower extremity deep venous thrombosis-current UEDVT treatment guidelines may be overly aggressive. The goal of this study was to review outcomes of line-associated UEDVT in critically ill patients and to define the efficacy of current treatment protocols in pulmonary embolism (PE) prevention while avoiding hemorrhagic complications.

METHODS

A retrospective review was performed of 193 consecutive patients admitted to the medical and surgical intensive care unit (ICU) at a tertiary care hospital between 2009 and 2014 diagnosed with acute line-associated UEDVT by duplex ultrasound. The examined treatment arms included anticoagulation with intent to reach therapeutic levels, prophylactic or subtherapeutic anticoagulation, and no anticoagulation. Primary outcomes included major hemorrhage (defined as any intracranial hemorrhage or any hemorrhage resulting in transfusion, ICU readmission, or death), PE, in-hospital mortality, total hospital length of stay (LOS), and ICU LOS.

RESULTS

Of the 10,907 patients, 161 (1.48%) were diagnosed with acute line-associated UEDVT, 81 of 6027 in the medical ICU (1.34%) and 80 of 4880 in the surgical ICU (1.64%), after exclusion of 32 patients with concurrent lower extremity deep venous thrombosis. In total, 122 patients (75.8%) received anticoagulation with intent to reach therapeutic levels, 23 (14.3%) received prophylactic anticoagulation, and 16 (9.94%) received no anticoagulation. Major hemorrhage was significantly more common than symptomatic PE in all patients (15.5% vs 4.97%; P < .001). A single fatal PE and two fatal hemorrhages were recorded across the series. There was no significant difference in in-hospital mortality (34.8% vs 16.7%; P = .726) or ICU LOS (33.1 vs 18.3 days; P = .739) for patients who developed major hemorrhage or symptomatic PE. On multivariate analysis, incidence of symptomatic PE was not significantly related to Acute Physiology and Chronic Health Evaluation III score (P = .963), anticoagulation regimen (P = .940), catheter type (P = .313), or bacteremia (P = .833).

CONCLUSIONS

Major hemorrhagic complications are more common than symptomatic PE after anticoagulation for line-associated UEDVT in ICU patients, raising concern that current treatment guidelines are too aggressive. These data necessitate further prospective investigation to determine the optimal treatment protocol for line-associated UEDVT in this critically ill cohort.

Vein Diameter for Peripherally Inserted Catheter Insertion: A Scoping Review

Background: The risk of venous thromboembolism (VTE) may be reduced if a vein of appropriate diameter is used for peripherally inserted central catheter (PICC) insertion. However, clinicians may have predilections to cannulate certain vein types and use particular insertion sites (eg, right or left arm) and therefore do not necessarily assess all veins available to determine the most optimal vessel to introduce a catheter. It is important that clinicians have an understanding of the diameter of veins used for PICC insertion and the effect of patient factors such as hand dominance on vein size to determine whether their clinical practice is appropriate.

Methods: A scoping review of published literature was performed to determine existing knowledge regarding the diameters of veins used for PICC insertion and the influence of patient factors such as hand dominance and laterality (left or right arm) on vein size.

Results: There was limited published research about the diameters of the basilic, brachial, and cephalic veins at the midupper arm, with only 6 studies identified. Three of the 6 selected articles focused on vein diameter measurement to inform arteriovenous fistula development. Only 1 study included participants undergoing PICC insertion. Scant research examined the effect of laterality on vein diameter and 1 study was identified that reported the influence of hand dominance or vein type on the diameter of veins used for PICC insertion.

Conclusions: This review found that there is a paucity of studies that have examined the veins used for PICC insertion. Nevertheless, it appears that the basilic vein has the largest diameter (with smaller brachial and cephalic veins), although this is not always the case. Laterality and hand dominance does not seem to influence vein diameter. Further research about the vasculature used for PICC insertion is needed to inform clinical practice.

The dwell time and survival rates of PICC placement after balloon angioplasty in patient with unexpected central venous obstruction

PURPOSE

To evaluate the dwell time and actual survival rates of peripherally inserted central catheter (PICC) placements after balloon angioplasty in patients with unexpected central venous obstructions.

MATERIALS AND METHODS

Data were obtained on all PICC insertions performed in a tertiary care hospital from August 2008 to December 2013. Thirty-five PICCs attempted after balloon angioplasty in 25 patients (15 male and 10 female patients; mean age, 63 years). Fisher's exact test was used to test for differences in reasons for catheter removal between the groups of patients with stenosis or obstructions. Survival curves for PICC dwell time of all patients, stenosis group, and obstruction group were generated separately using Kaplan-Meier survival analysis and compared with log-rank tests.

RESULTS

There were a total 21 obstructions and 14 stenoses. The overall technical success rate of PICC placement after balloon angioplasty was 94% (33 of 35 procedures). The PICC dwell time was determined for 27 PICCs and ranged from 4 to 165 days (mean, 39.6 days). Among all PICCs, 16 were removed early, resulting in an actual survival rate of 40.7% (11 of 27 PICCs). There were no significant differences in reasons for catheter removal between the stenosis and obstruction groups (p = 0.24). The dwell times for both groups were not significantly different by Kaplan-Meier analysis (p = 0.54).

CONCLUSIONS

PICC placement after balloon angioplasty is a good treatment option for patients with unexpected central venous lesions, and offers high technical success rates. The actual survival rate was relatively lower (40.7%) than that from previous studies.

Risk factors associated with catheter-related upper extremity deep vein thrombosis in patients with peripherally inserted central venous catheters: a prospective observational cohort study: part 2

This is the second part of a 2-part series that reports on the results of a prospective observational cohort study designed to examine risk factors associated with symptomatic upper extremity deep vein thrombosis (UEDVT) in patients with peripherally inserted central catheters (PICCs). Part 1, published in the May/June 2014 issue of the Journal of Infusion Nursing, provided an extensive review and critique of the literature regarding risk factors associated with catheter-related UEDVT and identified 28 suspected risk factors. A study was undertaken to examine each of the risk factors among 203 acute care patients with PICCs, 13 of whom experienced a UEDVT, yielding an incidence of 6.4%. The most common reason for admission was infection (33.5%), and the primary reason for insertion of the PICC was venous access (58.6%). Hypertension (P = .022) and obesity (P = .008), defined as a body mass index ≥30, were associated with UEDVT. The clinical symptoms of edema (P < .001) and a 3-cm or more increase in arm circumference (P < .001) in the PICC arm after PICC placement were associated with UEDVT. All other variables were not statistically significant. The results suggest that patients who are obese and hypertensive may be at greater risk for the development of UEDVT and that the physical finding of edema and increased arm circumference in the PICC arm are possibly suggestive of UEDVT.

Peripherally inserted central venous catheter safety in burn care: a single-center retrospective cohort review

The use of peripherally inserted central catheter (PICC) line for central venous access in thermally injured patients has increased in recent years despite a lack of evidence regarding safety in this patient population. A recent survey of invasive catheter practices among 44 burn centers in the United States found that 37% of burn units use PICC lines as part of their treatment protocol. The goal of this study was to compare PICC-associated complication rates with the existing literature in both the critical care and burn settings. The methodology involved is a single institution retrospective cohort review of patients who received a PICC line during admission to a regional burn unit between 2008 and 2013. Fifty-three patients were identified with a total of seventy-three PICC lines. The primary outcome measurement for this study was indication for PICC line discontinuation. The most common reason for PICC line discontinuation was that the line was no longer indicated (45.2%). Four cases of symptomatic upper extremity deep vein thrombosis (5.5%) and three cases of central line-associated bloodstream infection (4.3%, 2.72 infections per 1000 line days) were identified. PICC lines were in situ an average of 15 days (range 1 to 49 days). We suggest that PICC line-associated complication rates are similar to those published in the critical care literature. Though these rates are higher than those published in the burn literature, they are similar to central venous catheter-associated complication rates. While PICC lines can be a useful resource in the treatment of the thermally injured patient, they are associated with significant and potentially fatal risks.

The Michigan Appropriateness Guide for Intravenous Catheters (MAGIC): Results From a Multispecialty Panel Using the RAND/UCLA Appropriateness Method

Use of peripherally inserted central catheters (PICCs) has grown substantially in recent years. Increasing use has led to the realization that PICCs are associated with important complications, including thrombosis and infection. Moreover, some PICCs may not be placed for clinically valid reasons. Defining appropriate indications for insertion, maintenance, and care of PICCs is thus important for patient safety. An international panel was convened that applied the RAND/UCLA Appropriateness Method to develop criteria for use of PICCs. After systematic reviews of the literature, scenarios related to PICC use, care, and maintenance were developed according to patient population (for example, general hospitalized, critically ill, cancer, kidney disease), indication for insertion (infusion of peripherally compatible infusates vs. vesicants), and duration of use (≤5 days, 6 to 14 days, 15 to 30 days, or ≥31 days). Within each scenario, appropriateness of PICC use was compared with that of other venous access devices. After review of 665 scenarios, 253 (38%) were rated as appropriate, 124 (19%) as neutral/uncertain, and 288 (43%) as inappropriate. For peripherally compatible infusions, PICC use was rated as inappropriate when the proposed duration of use was 5 or fewer days. Midline catheters and ultrasonography-guided peripheral intravenous catheters were preferred to PICCs for use between 6 and 14 days. In critically ill patients, nontunneled central venous catheters were preferred over PICCs when 14 or fewer days of use were likely. In patients with cancer, PICCs were rated as appropriate for irritant or vesicant infusion, regardless of duration. The panel of experts used a validated method to develop appropriate indications for PICC use across patient populations. These criteria can be used to improve care, inform quality improvement efforts, and advance the safety of medical patients.

Comparison of complications associated with peripherally inserted central catheters and Hickman™ catheters in patients with intestinal failure receiving home parenteral nutrition. Six-year follow up study

BACKGROUND & AIM

Patients with intestinal failure (IF) are dependent on parenteral nutrition delivered through central access such as Hickman™ catheters. The peripherally inserted central catheter (PICC) is becoming increasingly popular for the purpose. The aim of the present study was to compare complication rates between the two types of catheters.

PATIENTS AND METHODS

Over a six-year period (2008-2014), we included 136 patients with IF receiving home parenteral nutrition (HPN). These patients had a total of 295 catheters (169 Hickman™ catheters and 126 PICCs). Data were collected by reviewing their medical records. Incidences are given per 1000 catheter days. Data are given as means ± standard deviation (SD) and compared using independent student's t-tests, Mann-Whitney-Wilcoxon, and X(2)-tests. A survival analysis for time to the first infection was conducted using Cox regression.

RESULTS

The total number of catheter days was 54,912 days for Hickman™ catheters (mean dwell time 325 ± 402) and 15,974 days for PICCs (mean dwell time 127 ± 121), respectively. The incidence of catheter-related blood stream infection (CRBSI) per 1000 catheter days was significantly lower for Hickman™ catheters compared to PICCs (0.56 vs. 1.63, p < 0.05). The mean time to first CRBSI was significantly shorter for PICCs compared to Hickman™ catheters (84 ± 94 days vs. 297 ± 387 days, p < 0.05), which was confirmed with a cox analysis corrected for age and gender. A total of 75 catheters were removed due to CRBSI, 49 Hickman™ catheters and 26 PICCs respectively. In addition, PICCs were more often removed due to local infection/phlebitis and mechanical causes (p < 0.001).

CONCLUSION

We found a higher risk and shorter time to first CRBSI in PICCs compared to Hickman catheters supporting that PICCs should mainly be chosen for planned HPN up to 3-6 months. We therefore conclude that the choice of catheter must still be determined on an individual basis.

Quality improvement initiative to reduce deep vein thrombosis associated with peripherally inserted central catheters in adults with cystic fibrosis

RATIONALE

Peripherally inserted central catheters (PICCs) are common in the treatment of patients with cystic fibrosis (CF). Previous reports suggest that patients with CF are at increased risk for PICC-associated deep vein thrombosis (DVT).

OBJECTIVES

We assessed potential risk factors for symptomatic PICC-associated DVT with subsequent implementation of a quality improvement (QI) initiative to reduce PICC-associated DVT in patients with CF.

METHODS

This was a 5-year retrospective cohort study with subsequent 21-month prospective observation following implementation of a QI intervention in adults (aged 18 yr or older) with CF. All patients with a PICC inserted from July 2006 to March 2013 at our CF Foundation-accredited center were included. Symptomatic DVT was diagnosed by Doppler ultrasound. PICC insertions were analyzed, and nine risk factors for DVT were analyzed to formulate a QI initiative to reduce risk of PICC-associated DVT. The QI program focused on staff education and included modification to PICC order entry with a 4 French (F) single-lumen (SL) catheter as standard for all patients with CF.

MEASUREMENTS AND MAIN RESULTS

A total of 369 PICCs were analyzed in 117 unique patients for a total of 5,437 PICC-days of placement. Symptomatic DVT was diagnosed in 28 (7.6%) of the 369 PICCs analyzed. Using regression analysis, the strongest predictors for DVT occurrence were warfarin use (odds ratio [OR] = 9.2, P = 0.006) and history of PICC-associated DVT (OR = 2.97, P = 0.08). Insertion of a 4F SL PICC resulted in zero symptomatic DVT. Zero episodes of DVT associated with 4F PICC insertion prevented use of PICC size in regression analysis. However, univariate analysis revealed that insertion of a 4F SL PICC instead of either 5F double lumen or 6F triple lumen was associated with a reduction in PICC-associated DVT (P = 0.001). After the QI intervention, 4F SL catheter insertion substantially increased to 65.8% of all PICCs inserted, whereas 6F triple-lumen catheter insertion declined to 6.8% of PICCs inserted. The QI initiative resulted in an absolute risk reduction in DVT per PICC placed of 6.1% (P = 0.055).

CONCLUSIONS

To reduce risk of PICC-associated DVT in patients with CF, QI strategies should focus on insertion of smaller-diameter 4F PICCs and reduction in PICC use in high-risk patients when possible.

Risk factors associated with catheter-related upper extremity deep vein thrombosis in patients with peripherally inserted central venous catheters: literature review: part 1

This is part 1 of a 2-part series of articles that report on the results of a prospective observational cohort study designed to examine the risk factors associated with symptomatic upper extremity deep vein thrombosis (UEDVT) in patients with peripherally inserted central catheters. This article provides an extensive review and critique of the literature that serves to explicate what is currently known about risk factors associated with catheter-related UEDVT. Risk factors such as anticoagulant use, cancer, infection, hypertension, catheter tip placement, and catheter size were identified most frequently in the literature as being associated with UEDVT development. Other risk factors--such as obesity, smoking history, surgery, and presence of pain or edema--were examined in a limited number of studies and lacked consistent evidence of their impact on UEDVT development. The subsequent study that evolved from the review of the literature investigates the relationship between identified risk factors and UEDVT development.

Peripherally inserted central catheter thrombosis incidence and risk factors in cancer patients: a double-center prospective investigation

BACKGROUND

Peripherally inserted central catheters (PICCs) are widely used in chemotherapy, but the reported PICC thrombosis incidence varies greatly, and risks of PICC thrombosis are not well defined. This study was to investigate the incidence and risk factors of PICC-related upper extremity vein thrombosis in cancer patients.

METHODS

This was a prospective study conducted in two tertiary referral hospitals from May 2010 to February 2013. Cancer patients who were subject to PICC placement were enrolled and checked by Doppler ultrasound weekly for at least 1 month. Univariable and multivariable logistic regression analyses were applied for identification of risk factors.

RESULTS

Three hundred and eleven cancer patients were enrolled in the study. One hundred and sixty (51.4%) developed PICC thrombosis, of which 87 (54.4%) cases were symptomatic. The mean time interval from PICC insertion to thrombosis onset was 11.04±5.538 days. The univariable logistic regression analysis showed that complications (odds ratio [OR] 1.686, P=0.032), less activity (OR 1.476, P=0.006), obesity (OR 3.148, P=0.000), and chemotherapy history (OR 3.405, P=0.030) were associated with PICC thrombosis. Multivariate analysis showed that less activity (OR 9.583, P=0.000) and obesity (OR 3.466, P=0.014) were significantly associated with PICC thrombosis.

CONCLUSIONS

The incidence of PICC thrombosis is relatively high, and nearly half are asymptomatic. Less activity and obesity are risk factors of PICC-related thrombosis.

Screening for novel risk factors related to peripherally inserted central catheter-associated complications

BACKGROUND

Peripherally inserted central catheters (PICCs) are increasingly utilized. Patient and system factors that increase risk of complications should be identified to avoid preventable patient harm.

METHODS

A case control analysis of adult inpatients who underwent PICC placement from January 2009 to January 2010 at Scott & White Memorial Hospital was conducted to determine the incidence and risk factors for complications. One hundred seventy cases of inpatients who experienced PICC-related complications were identified. Age- and gender-matched controls were randomly selected among patients who underwent PICC placement without documented complications during this time.

RESULTS

A total of 1444 PICCs were placed, with a complication rate of 11.77% (95% confidence interval: 10.11%-13.44%). Complications included catheter-associated thrombosis (3%), mechanical complications (4%), catheter-associated bloodstream infections (2%), and cellulitis (1%). In multivariable logistic regression analyses, malnutrition and after-hours placement were significantly associated with increased risk of complications, as was body mass index (BMI) >30 after adjusting for anticoagulation and time of placement. In a secondary multivariable logistic regression analysis, after-hours placement and malnutrition were significantly associated with increased risk of nonmechanical complications. Additionally, in conditional univariate analyses, length of stay, malnutrition, and after-hours placement were associated with increased risk of catheter-associated thrombosis. In our multivariable logistic regression analyses, use of anticoagulation/antiplatelet agents was associated with decreased risk of all-cause complications, nonmechanical complications, and catheter-associated thrombosis.

CONCLUSIONS

Screening of patients undergoing PICC placement with attention to malnutrition, BMI >30, and length of stay may reduce the risk of PICC-associated complications. Use of anticoagulation/antiplatelet agents and avoiding after-hours placement may reduce complications and enhance patient safety.

Clinical guidelines on central venous catheterisation. Swedish Society of Anaesthesiology and Intensive Care Medicine

Safe and reliable venous access is mandatory in modern health care, but central venous catheters (CVCs) are associated with significant morbidity and mortality, This paper describes current Swedish guidelines for clinical management of CVCs The guidelines supply updated recommendations that may be useful in other countries as well. Literature retrieval in the Cochrane and Pubmed databases, of papers written in English or Swedish and pertaining to CVC management, was done by members of a task force of the Swedish Society of Anaesthesiology and Intensive Care Medicine. Consensus meetings were held throughout the review process to allow all parts of the guidelines to be embraced by all contributors. All of the content was carefully scored according to criteria by the Oxford Centre for Evidence-Based Medicine. We aimed at producing useful and reliable guidelines on bleeding diathesis, vascular approach, ultrasonic guidance, catheter tip positioning, prevention and management of associated trauma and infection, and specific training and follow-up. A structured patient history focused on bleeding should be taken prior to insertion of a CVCs. The right internal jugular vein should primarily be chosen for insertion of a wide-bore CVC. Catheter tip positioning in the right atrium or lower third of the superior caval vein should be verified for long-term use. Ultrasonic guidance should be used for catheterisation by the internal jugular or femoral veins and may also be used for insertion via the subclavian veins or the veins of the upper limb. The operator inserting a CVC should wear cap, mask, and sterile gown and gloves. For long-term intravenous access, tunnelled CVC or subcutaneous venous ports are preferred. Intravenous position of the catheter tip should be verified by clinical or radiological methods after insertion and before each use. Simulator-assisted training of CVC insertion should precede bedside training in patients. Units inserting and managing CVC should have quality assertion programmes for implementation and follow-up of routines, teaching, training and clinical outcome. Clinical guidelines on a wide range of relevant topics have been introduced, based on extensive literature retrieval, to facilitate effective and safe management of CVCs.

Peripherally inserted central catheter (PICC)-related thrombosis in critically ill patients

BACKGROUND

Peripherally inserted central catheters (PICC) are being increasingly used in critical care setting. However, PICCs are associated with a number of complications, particularly upper extremity venous thrombosis (UEVT), leading to post-thrombotic syndrome, pulmonary embolism and increased risk of catheter-related infection.

OBJECTIVE

To review the literature surrounding PICCs and highlight the epidemiology, pathophysiology, diagnosis and management of PICC-related thrombosis in critically ill patients.

DATA SOURCES AND EXTRACTION

We performed an electronic literature search of the databases PubMed, EMBASE and Google scholar using set search terms, from their commencement date to the end of January 2014.

SUMMARY OF REVIEW

It has been shown that PICCs may double the risk of deep venous thrombosis compared with centrally inserted venous catheters, in critically ill patients. However, the incidence of PICC-related thrombosis in critically ill patients has not been quantified. Ultrasonography is the preferred diagnostic imaging modality. There are no randomized controlled trials (RCTs) on the best treatment of PICC-related thrombosis in the intensive care unit (ICU) setting and in most cohort studies, anticoagulation strategies with or without PICC removal have been used.

CONCLUSIONS

Decision to insert a PICC should be taken after careful risk stratification. There is lack of high-quality evidence assessing prevention strategies and management of PICC-related thrombosis in the ICU. Well-designed RCTs are required to estimate the prevalence of UEVT in ICU patients with PICCs and evaluate the efficacy and magnitude of clinical benefit and cost-effectiveness of therapeutic strategies.

Right to left shunting through communications between the left superior intercostal vein tributaries and the left atrium: a potential cause of paradoxical embolism

OBJECTIVES

To investigate the role of collateral venous pathways between the left brachiocephalic vein (LBV) and the left atrium through an arcade comprising the left superior intercostal vein (LSICV), left vertical vein (LVV), and pulmonary veins as a potential cause of paradoxical embolism.

METHODS

A retrospective search was performed to find symptomatic patients with negative work up for paradoxical emboli whose chest CT or MR angiography by left arm contrast injection showed a visible right to left shunt through the LSICV/LVV collateral pathway (symptomatic group). We also evaluated the characteristics of this collateral pathway in 150 chest CT angiographies from general referrals (comparison group).

RESULTS

We found 7 symptomatic patients. Initial presentations included neurological symptoms in all patients and episodes of hypoxemia in three patients. Communications between the LBV and left atrium through the LSICV/LVV pathway was seen is all 7 cases and confirmed by transesophageal echocardiography in two. An abnormal LBV was seen in 6 cases (absence in one, stenosis in 5). Moderate superior vena cava stenosis was seen in one and acute right subclavian vein thrombosis in one. Six patients had past history of an upper extremity central line placement. In the comparison group, LSICV was seen in 73 (48%), connecting to the hemiazygos vein in 41, to a LVV in 19 and to the left atrium in 7.

CONCLUSION

LSICV/LVV collaterals are common and can be a potential route for paradoxical emboli especially when stenosis of a draining vein such as LBV exists.

Risk of venous thromboembolism associated with peripherally inserted central catheters: a systematic review and meta-analysis

BACKGROUND

Peripherally inserted central catheters (PICCs) are associated with an increased risk of venous thromboembolism. However, the size of this risk relative to that associated with other central venous catheters (CVCs) is unknown. We did a systematic review and meta-analysis to compare the risk of venous thromboembolism associated with PICCs versus that associated with other CVCs.

METHODS

We searched several databases, including Medline, Embase, Biosis, Cochrane Central Register of Controlled Trials, Conference Papers Index, and Scopus. Additional studies were identified through hand searches of bibliographies and internet searches, and we contacted study authors to obtain unpublished data. All human studies published in full text, abstract, or poster form were eligible for inclusion. All studies were of adult patients aged at least 18 years who underwent insertion of a PICC. Studies were assessed with the Newcastle-Ottawa risk of bias scale. In studies without a comparison group, the pooled frequency of venous thromboembolism was calculated for patients receiving PICCs. In studies comparing PICCs with other CVCs, summary odds ratios (ORs) were calculated with a random effects meta-analysis.

FINDINGS

Of the 533 citations identified, 64 studies (12 with a comparison group and 52 without) including 29 503 patients met the eligibility criteria. In the non-comparison studies, the weighted frequency of PICC-related deep vein thrombosis was highest in patients who were critically ill (13·91%, 95% CI 7·68-20·14) and those with cancer (6·67%, 4·69-8·64). Our meta-analysis of 11 studies comparing the risk of deep vein thrombosis related to PICCs with that related to CVCs showed that PICCs were associated with an increased risk of deep vein thrombosis (OR 2·55, 1·54-4·23, p<0·0001) but not pulmonary embolism (no events). With the baseline PICC-related deep vein thrombosis rate of 2·7% and pooled OR of 2·55, the number needed to harm relative to CVCs was 26 (95% CI 13-71).

INTERPRETATION

PICCs are associated with a higher risk of deep vein thrombosis than are CVCs, especially in patients who are critically ill or those with a malignancy. The decision to insert PICCs should be guided by weighing of the risk of thrombosis against the benefit provided by these devices.

FUNDING

None.