Confirmation of correct central venous catheter position in the preoperative setting by echocardiographic "bubble-test".

BACKGROUND: Verification of the central venous catheters (CVCs) position by chest X-ray (CXR) is usually performed in the postoperative period with the risk related to possible malposition. This prospective observational study aimed to assess the diagnostic accuracy and reproducibility of ultrasound (US) and "bubble test" to detect malpositions of CVC in the preoperative setting. METHODS: The study included 105 patients undergoing preoperative CVC placement. A US protocol aimed at direct visualization of the CVC was completed by a single operator and two consecutive "bubble tests" were performed independently by different physicians. Two parameters were considered: complete right atrium (RA) opacization versus visualization of "no or few bubbles" and time from agitated saline injection to visualization of micro-bubbles in the RA ("push-to-bubbles" time). RESULTS: CXR identified 14 (13%) CVC malpositions. Vascular US showed a sensitivity of 64% and a specificity of 100% while visualization of "no or few bubbles" at bubble test yielded a sensitivity of 50% and a specificity of 100%. "Push-to-bubbles" times were ≈9 times longer in patients with compared to those without CVC malposition (1400 [702-2160] ms versus 167 [123-228] ms, P<0.001). A cut off value of 500 ms had a sensitivity of 100% and a specificity of 99% for CVC malposition with an inter-observer agreement of 99% (kappa 0.96, P<0.001). CONCLUSION: CVC malposition was observed in a sizeable proportion of patients undergoing preoperative central venous cannulation. Measurement of "push-to-bubbles" time is a fast, accurate and highly reproducible tool for verifying the correct CVC position.

[Anesthesia with propofol and atracurium in a case of porphyria cutanea tarda]. / Anestesia con propofol e atracurium in un caso di porfiria cutanea tarda.

The conduction of anaesthesia in a patient with a diagnosis of porphyria cutanea tarda is described. The aim of this paper is to provide further evidence for safety of TIVA (Total Intra Venous Anaesthesia) paying particular attention to propofol and atracurium (there are not sufficient data about it in the literature) in patients with porphyria cutanea tarda and high levels of uroporphyrin. The study of the anaesthetic management of a patient suffering from Porphyria Cutanea Tarda (PCT), the most common form of porphyria, can offer useful indications. Due to the fact that PCT is less severe than the acute forms, there is less risk for the patient under anaesthesia. In this particular case preoperative, intraoperative and postoperative urinary porphyrin are compared and furthermore, the liver function and the eventual development of skin lesions are monitored. A not significant increase of urinary porphyrin levels after surgery, no skin lesions and no modifications of liver function have been observed. TIVA proved to be safe in this case of PCT.