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CON: Manometry During Internal Jugular Cannulation: Case Not Proven

2009; Lippincott Williams & Wilkins; Volume: 109; Issue: 1 Linguagem: Inglês

10.1213/ane.0b013e31818e462c

1526-7598

Bruce J. Leone,

Vascular Procedures and Complications

In the current issue of Anesthesia & Analgesia, Ezaru et al.1 have presented data collected over a 15-year period regarding internal jugular vein cannulation and inadvertent carotid artery cannulation. After a single sentinel event, the authors’ group instituted a mandatory policy of examining the blood return in a piece of extension tubing to determine whether the cannulation needle was located in the carotid artery before placement of a large bore indwelling cannula. The authors report no adverse events in 15 years, comprising 9859 internal jugular vein cannulations, of inadvertent arterial cannulation and arterial injury. The authors have thus suggested that all internal jugular vein cannulae be placed after this simplistic method of manometry to eliminate arterial cannulation and injury. The literature is replete with unfortunate case reports of carotid arterial puncture and cannulation resulting in injury and morbidity. However, it is difficult to gain insight into the relative risk of mishap given the vast number of internal jugular vein cannulations and the unreported percentage of mishaps. Ezaru et al. report an arterial puncture (without cannulation) rate of 5% in 511 internal jugular vein cannulation attempts; a similar arterial puncture rate has been reported,2 as well as an almost identical incidence reported earlier by Jobes et al.3 Indeed, as Ezaru et al.1 emphasize, the incidence of arterial puncture is significantly higher than the incidence of carotid cannulation. However, can one make the case for adoption of simple manometry (without pressure transduction) as de rigueur practice before placement of an internal jugular large-bore cannula? The data are compelling from the aspect of avoidance of a potentially lethal complication, but is the risk-benefit ratio sufficient to change practice? The authors1 speculate that the absence of carotid injury mishaps in their 15 years of required manometry would suggest adoption of manometry with a high benefit, yet the incidence quoted of inadvertent arterial cannula placement is vanishingly small, varying from 0.0995% to 0.775%.4 Thus, assuming Ezaru et al. have an extremely low incidence of arterial cannula placement, one would expect to see 1 possible arterial cannulation in 10,000 patients. The fact that no arterial cannulation was seen could be the natural variability associated with random chance (or rare events), rather than an elimination of the event due to changes in practice. And what of the potential risks in adding an extra task to the already intricate performance of internal jugular cannulation? In manipulating the 18-gauge cannula to affix the extension tubing and then aspirating or manipulating the cannula tubing to obtain a sufficient column of blood, one could envision many other mishaps: air embolization, dislodgement of the cannula, infection and violation of the sterile field are very real possibilities not discussed in Ezaru et al.’s study. While these may be viewed as negligible risks or unlikely, an incidence of more than 1 in 10,000 cases would obviate some of the benefit gained by performing manometry. The outcomes may not be significant initially (e.g., blood loss), but may become severe and/or debilitating (e.g., infection or air embolization). Even if one considers the higher rate of reported incidence (0.775%) of inadvertent carotid cannulation, an incidence of manometry-induced mishaps of once a year would be more than double the incidence of carotid cannulation injury with standard techniques. Ezaru et al. regrettably did not have data on the incidence of carotid cannulation before the inception of mandatory manometry. Data quoted above4 suggest that this singular catastrophic incident, which occasioned mandatory manometry, may have been the only incident at the authors’ institution in the preceding 15 years (assuming approximately 10,000 cannulations per 15 years). Thus, the results presented in their article concerning manometry may be statistically unrelated to the application of routine manometry. Although the prospective data of 4 in 511 unrecognized arterial punctures suggests that cannulae may have been placed without the performance of manometry, this incidence (8%) is extremely high for inadvertent large-bore carotid cannulation. The manometry Ezaru et al. describe is simple and fosters some sense of security, but the data presented do not make the case for routine application of this technique in practice. If one accepts the risks associated with the traditional methods of internal jugular cannulation, this maximum reported risk (7 in 10,000) is less than the mortality risk associated with anesthesia in ASA physical status 3 patients (8 in 10,877) or ASA physical status 4 patients (34 in 2939),5 groups in whom internal jugular cannulation is most likely to be performed. While it is unknown what role invasive monitoring mishaps played in the overall mortality figures presented by Lagasse,5 it is clear that internal jugular cannulation without mandatory manometry is as safe as the administration of anesthesia. Acceptance of status quo limits quality improvements in our specialty. Therefore, we should not shrug and accept that “What if this is as good as it gets?” (with apologies to Jack Nicholson) but rather look critically at our performance of internal jugular cannulation and improve our technique. Ezaru et al. mention en passant the use of ultrasound in assisting internal jugular cannulation but discount this as not user friendly when compared to simple manometry. Perhaps our improvements will come with improved availability of and facility with of ultrasound, which can readily identify structures and detect successful cannulation of the internal jugular vein. Manometry can only detect arterial placement of the cannula, whereas ultrasound can identify the internal jugular vein before placement of the finder needle as well as arterial placement of an 18-gauge catheter. Use of ultrasound in highly dangerous situations with the potential for serious complications, such as the liver failure patient or the fully anticoagulated patient arriving from unsuccessful coronary artery interventions, may be the entrée needed to propel ultrasound to the forefront of technological requirement for internal jugular cannulation. Caution is warranted here, however, as carotid puncture despite the use of ultrasound to detect apparent successful internal jugular puncture continue to be reported; however, like Ezaru et al., these authors also report zero arterial cannulations.6 Manometry, while providing a comforting affirmation before large-bore indwelling cannula placement, is not the answer.