Mauro Pittiruti

ESPEN Guidelines on Parenteral Nutrition: central venous catheters (access, care, diagnosis and therapy of complications).

When planning parenteral nutrition (PN), the proper choice, insertion, and nursing of the venous access are of paramount importance. In hospitalized patients, PN can be delivered through short-term, non-tunneled central venous catheters, through peripherally inserted central catheters (PICC), or - for limited period of time and with limitation in the osmolarity and composition of the solution - through peripheral venous access devices (short cannulas and midline catheters). Home PN usually requires PICCs or - if planned for an extended or unlimited time - long-term venous access devices (tunneled catheters and totally implantable ports). The most appropriate site for central venous access will take into account many factors, including the patients conditions and the relative risk of infective and non-infective complications associated with each site. Ultrasound-guided venepuncture is strongly recommended for access to all central veins. For parenteral nutrition, the ideal position of the catheter tip is between the lower third of the superior cava vein and the upper third of the right atrium; this should preferably be checked during the procedure. Catheter-related bloodstream infection is an important and still too common complication of parenteral nutrition. The risk of infection can be reduced by adopting cost-effective, evidence-based interventions such as proper education and specific training of the staff, an adequate hand washing policy, proper choices of the type of device and the site of insertion, use of maximal barrier protection during insertion, use of chlorhexidine as antiseptic prior to insertion and for disinfecting the exit site thereafter, appropriate policies for the dressing of the exit site, routine changes of administration sets, and removal of central lines as soon as they are no longer necessary. Most non-infective complications of central venous access devices can also be prevented by appropriate, standardized protocols for line insertion and maintenance. These too depend on appropriate choice of device, skilled implantation and correct positioning of the catheter, adequate stabilization of the device (preferably avoiding stitches), and the use of infusion pumps, as well as adequate policies for flushing and locking lines which are not in use.

International evidence-based recommendations on ultrasound-guided vascular access

PurposeTo provide clinicians with an evidence-based overview of all topics related to ultrasound vascular access.MethodsAn international evidence-based consensus provided definitions and recommendations. Medical literature on ultrasound vascular access was reviewed from January 1985 to October 2010. The GRADE and the GRADE-RAND methods were utilised to develop recommendations.ResultsThe recommendations following the conference suggest the advantage of 2D vascular screening prior to cannulation and that real-time ultrasound needle guidance with an in-plane/long-axis technique optimises the probability of needle placement. Ultrasound guidance can be used not only for central venous cannulation but also in peripheral and arterial cannulation. Ultrasound can be used in order to check for immediate and life-threatening complications as well as the catheter’s tip position. Educational courses and training are required to achieve competence and minimal skills when cannulation is performed with ultrasound guidance. A recommendation to create an ultrasound curriculum on vascular access is proposed. This technique allows the reduction of infectious and mechanical complications.ConclusionsThese definitions and recommendations based on a critical evidence review and expert consensus are proposed to assist clinicians in ultrasound-guided vascular access and as a reference for future clinical research.

The electrocardiographic method for positioning the tip of central venous catheters

Tip position of a central venous access is of paramount importance and should be verified before starting infusion. Intra-procedural methods for verifying the location of the tip are to be preferred, since they avoid the risks, delays and costs of repositioning the tip. Among the intra-procedural methods, the electrocardiography (EKG) method has many advantages since it is as accurate as fluoroscopy, but simpler, more readily available, less expensive, safer and more cost-effective. The only contraindication to utilizing the EKG method is the difficulty in identifying the standard P-wave on a surface EKG (this happens - usually because of severe arrhythmias, such as atrial fibrillation - in only approximately 7% of cases: although such patients are easily identified before the procedure, and are referred to other methods for tip positioning). When dealing with the insertion of peripherally inserted central catheters (PICC), the EKG method (using the column of saline technique) virtually has no risk of false positives. The EKG method removes the need for the post-procedural chest x-ray, as long as there is no expected risk of pleuropulmonary damage to be ruled out (example: ultrasound guided central venipuncture for central venous catheter insertion or any kind of PICC insertion). In conclusion, evidence is mounting that the EKG method may be a valid and cost-effective alternative to the standard radiological control of the location of the tip of any central venous access device (VAD), and that will rapidly become the preferential method for confirming the tip position during PICC insertion.

The intracavitary ECG method for positioning the tip of central venous catheters: results of an Italian multicenter study

Purpose The aim of this multicenter study was to assess the feasibility, safety, and accuracy of the intracavitary ECG method for real-time positioning of the tip of different types of central venous catheters. Methods A total of 1444 catheter insertions in adult patients were studied in eight Italian centers (539 ports, 245 PICCs, 325 tunneled CVCs, 335 non-tunneled CVCs). Patients with no visible P wave at the standard baseline ECG were excluded. Depending on the type of catheter and its purpose, the target was to position the tip either (a) at the cavo-atrial junction, or (b) in the lower third of the superior vena cava, or (c) in the upper part of the atrium. The final position was verified by a post-procedural chest x-ray. Results The method was feasible in 99.3% of all cases. There were no complications potentially related to the method itself. At the final x-ray control, 83% of all tips were positioned exactly at the target; 12.4% were positioned within 1–2 cm from the target, but still in a correct central position; only 3.8% were malpositioned. The mismatch between intra-procedural ECG method and post-procedural x-ray was significantly lower when the x-ray was taken in supine position. Conclusions Our multicenter study confirms that the intracavitary ECG method for real time verification of tip position is accurate, safe, feasible in all adult patients and applicable to any type of short-term or long-term central venous access device.

Respiratory quotient and patterns of substrate utilization in human sepsis and trauma.

Three hundred measurements of indirect calorimetric and hemodynamic variables were performed in 99 critically ill septic and nonseptic surgical patients. Septics manifested, with respect to nonseptics, higher O2 consumption, metabolic rate and cardiac index, and lower respiratory quotient in the presence of higher glucose infusion rates and glucose infusion rate/metabolic rate ratios. Among septics there was a group of more severely ill patients with signs of multiple organ failure who manifested a dissociated pattern characterized by a tendency to decreased O2 consumption in the presence of increasing cardiac index and central venous O2 partial pressure: they had higher respiratory quotients, with respect to the other septics, for a given glucose infusion rate/metabolic rate ratio. The lower mean respiratory quotient of septics indicates that they depend generally more than nonseptic trauma patients on fat as an energy substrate and confirms a previously obtained evidence of limited hepatic lipogenesis in sepsis. At the same time, however, it is suggested that fat utilization becomes impaired (and hepatic lipogenesis becomes prominent) in sepsis at a stage in which signs of impaired oxidative metabolism and major metabolic abnormalities also develop.

Catheter-Related Complications in Cancer Patients on Home Parenteral Nutrition A Prospective Study of Over 51,000 Catheter Days

BACKGROUND Although home parenteral nutrition (HPN) is often indicated in cancer patients, many physicians are concerned about the risks potentially associated with the use of central venous access devices (VADs) in these patients. The aim of this prospective study was to investigate the actual incidence of VAD-related complications in cancer patients on HPN. METHODS All adult cancer patient candidates for VAD insertion and HPN were enrolled. The incidence of complications associated with 4 types of VADs (peripherally inserted central catheter [PICC], Hohn catheter, tunneled Groshong catheter, and port) was investigated, as well as the most significant risk factors. RESULTS Two hundred eighty-nine VADs in 254 patients were studied, for a total of 51,308 catheter-days. The incidence of catheter-related bloodstream infections (CRBSIs) was low (0.35/1000 catheter-days), particularly for PICCs (0/1000; P < .01 vs Hohn and tunneled catheters) and for ports (0.19/1000; P < .01 vs Hohn and P < .05 vs tunneled catheters). Mechanical complications were uncommon (0.8/1000), as was VAD-related venous thrombosis (0.06/1000). Ultrasound-guided venipuncture was associated with a decreased risk of CRBSI (P < .04) and thrombosis (P < .001). VAD securement using sutureless devices reduced the risk of CRBSI and dislocation (P < .001). Hohn catheters had no advantage over PICCs (higher complication rate and shorter dwell time; P < .001). CONCLUSIONS In cancer patients, HPN can be safely carried out with a low incidence of complications. Also, VADs are not equal in terms of complication rates, and strict adherence to meticulous insertion policies may effectively reduce catheter-related complications.

Plasma Carnitine Levels and Urinary Carnitine Excretion during Sepsis

Carnitine is an indispensable factor for the beta-oxidation of medium- and long-chain fatty acids, and it plays a possible role in the oxidation of branched-chain amino acids. Plasma and urinary levels of free carnitine and short-chain acyl-carnitines were studied in 67 surgical patients, after non-septic surgical procedures or during sepsis. The septic state was associated with increased urinary excretion of free carnitine (p less than 0.001), as well as with lower plasma levels of short-chain acyl-carnitines (p less than 0.001); the latter feature correlated with the level of hypermetabolism, as evaluated by the metabolic rate and by the arterial-mixed venous O2 difference. In 26 patients during total parenteral nutrition D, L-acetyl-carnitine was administered (100 mg/kg/24 hrs, in continuous iv infusion) and was associated, in septic patients only, with a significant decrease in the respiratory quotient, suggesting enhanced oxidation of low respiratory quotient substrates (fatty acids and/or branched-chain amino acids). Carnitine supplementation during total parenteral nutrition might be of theoretical benefit in some clinical conditions, such as sepsis, in which the following conditions coexist enhanced utilization of substrates whose oxidation is partially or totally carnitine dependent; prolonged absence of exogenous intake of carnitine (as in long-term total parenteral nutrition); eventual impairment of carnitine synthesis due to hepatic dysfunction; increased, massive urinary loss of carnitine.

Focus on peripherally inserted central catheters in critically ill patients

Venous access devices are of pivotal importance for an increasing number of critically ill patients in a variety of disease states and in a variety of clinical settings (emergency, intensive care, surgery) and for different purposes (fluids or drugs infusions, parenteral nutrition, antibiotic therapy, hemodynamic monitoring, procedures of dialysis/apheresis). However, healthcare professionals are commonly worried about the possible consequences that may result using a central venous access device (CVAD) (mainly, bloodstream infections and thrombosis), both peripherally inserted central catheters (PICCs) and centrally inserted central catheters (CICCs). This review aims to discuss indications, insertion techniques, and care of PICCs in critically ill patients. PICCs have many advantages over standard CICCs. First of all, their insertion is easy and safe -due to their placement into peripheral veins of the arm- and the advantage of a central location of catheter tip suitable for all osmolarity and pH solutions. Using the ultrasound-guidance for the PICC insertion, the risk of hemothorax and pneumothorax can be avoided, as well as the possibility of primary malposition is very low. PICC placement is also appropriate to avoid post-procedural hemorrhage in patients with an abnormal coagulative state who need a CVAD. Some limits previously ascribed to PICCs (i.e., low flow rates, difficult central venous pressure monitoring, lack of safety for radio-diagnostic procedures, single-lumen) have delayed their start up in the intensive care units as common practice. Though, the recent development of power-injectable PICCs overcomes these technical limitations and PICCs have started to spread in critical care settings. Two important take-home messages may be drawn from this review. First, the incidence of complications varies depending on venous accesses and healthcare professionals should be aware of the different clinical performance as well as of the different risks associated with each type of CVAD (CICCs or PICCs). Second, an inappropriate CVAD choice and, particularly, an inadequate insertion technique are relevant-and often not recognized-potential risk factors for complications in critically ill patients. We strongly believe that all healthcare professionals involved in the choice, insertion or management of CVADs in critically ill patients should know all potential risk factors of complications. This knowledge may minimize complications and guarantee longevity to the CVAD optimizing the risk/benefit ratio of CVAD insertion and use. Proper management of CVADs in critical care saves lines and lives. Much evidence from the medical literature and from the clinical practice supports our belief that, compared to CICCs, the so-called power-injectable peripherally inserted central catheters are a good alternative choice in critical care.

The intracavitary ECG method for positioning the tip of central venous access devices in pediatric patients: results of an Italian multicenter study

Purpose The Italian Group for Venous Access Devices (GAVeCeLT) has carried out a multicenter study investigating the safety and accuracy of intracavitary electrocardiography (IC-ECG) in pediatric patients. Methods We enrolled 309 patients (age 1 month-18 years) candidate to different central venous access devices (VAD) - 56 peripherally inserted central catheters (PICC), 178 short term centrally inserted central catheters (CICC), 65 long term VADs, 10 VADs for dialysis - in five Italian Hospitals. Three age groups were considered: A (<4 years, n = 157), B (4-11 years, n = 119), and C (12-18 years, n = 31). IC-ECG was applicable in 307 cases. The increase of the P wave on IC-ECG was detected in all cases but two. The tip of the catheter was positioned at the cavo-atrial junction (CAJ) (i.e., at the maximal height of the P wave on IC-ECG) and the position was checked during the procedure by fluoroscopy or chest x-ray, considering the CAJ at 1-2 cm (group A), 1.5-3 cm (group B), or 2-4 cm (group C) below the carina. Results There were no complications related to IC-ECG. The overall match between IC-ECG and x-ray was 95.8% (96.2% in group A, 95% in group B, and 96.8% in group C). In 95 cases, the IC-ECG was performed with a dedicated ECG monitor, specifically designed for IC-ECG (Nautilus, Romedex): in this group, the match between IC-ECG and x-ray was 98.8%. Conclusions We conclude that the IC-ECG method is safe and accurate in the pediatric patients. The applicability of the method is 99.4% and its feasibility is 99.4%. The accuracy is 95.8% and even higher (98.8%) when using a dedicated ECG monitor.

Virtual Reality: Emerging Role of Simulation Training in Vascular Access

Evolving new technologies in vascular access mandate increased attention to patient safety; an often overlooked yet valuable training tool is simulation. For the end-stage renal disease patient, simulation tools are effective for all aspects of creating access for peritoneal dialysis and hemodialysis. Based on aviation principles, known as crew resource management, we place equal emphasis on team training as individual training to improve interactions between team members and systems, cumulating in improved safety. Simulation allows for environmental control and standardized procedures, letting the trainee practice and correct mistakes without harm to patients, compared with traditional patient-based training. Vascular access simulators range from suture devices, to pressurized tunneled conduits for needle cannulation, to computer-based interventional simulators. Simulation training includes simulated case learning, root cause analysis of adverse outcomes, and continual update and refinement of concepts. Implementation of effective human to complex systems interaction in end-stage renal disease patients involves a change in institutional culture. Three concepts discussed in this article are as follows: (1) the need for user-friendly systems and technology to enhance performance, (2) the necessity for members to both train and work together as a team, and (3) the team assigned to use the system must test and practice it to a proficient level before safely using the system on patients.