Massive hemothorax due to subclavian vein tear during internal jugular vein cannulation in a 15-year-old boy scheduled for mitral valve replacement.

We present an unusual case of life-threatening hemothorax in a 15-year-old boy following subclavian vein tear during internal jugular vein (IJV) cannulation prior to initiation of surgery (mitral valve replacement). Successful IJV cannulation was done in the third attempt. However, we missed the subclavian tear which occurred during the first two initial attempts as there was no clinical evidence suggestive of it at that point of time. This undiagnosed hemothorax led to hemodynamic decompensation requiring high volume and inotropic support to wean the patient off cardiopulmonary bypass. This unusually high requirement of fluid and inotropes required the surgeon to look for noncardiac causes for the hemodynamic disturbance and he noticed a bulge in the right pleura, which on exploration had approximately 1.5 L of collected blood. It was then retrospectively analyzed that the cause of this hemothorax could have been the undue lateral orientation of the needle during IJV cannulation and the advancement of the dilator to its entire length could have injured the subclavian vein. Here, we also would like to discuss the safety precautions to be taken during the cannulation, like the needle orientation and the length to which the dilator must be advanced for safe central venous cannulation.

INTRODUCTION

Internal jugular vein (IJV) cannulation is associated with many serious complications like hemothorax, which may often be fatal.[1234] Most of these cases involve injury to the subclavian artery.[25] We present an unusual case of delayed diagnosis of life-threatening hemothorax following subclavian vein tear during IJV cannulation prior to initiation of surgery, leading to hemodynamic decompensation while weaning from cardiopulmonary bypass (CPB).

CASE REPORT

A 15-year-old boy was diagnosed to have mitral regurgitation with a floppy anterior mitral leaflet. He was also found to have retinitis pigmentosa and Marfan's syndrome. His exercise tolerance was adequate, and he did not have any symptoms suggestive of pulmonary hypertension or heart failure. No symptoms suggesting unstable atlanto-occipital joint were present. He was scheduled for mitral valve replacement. The decision to replace the valve as opposed to a repair was taken because extensive annular calcification was noted in the preoperative transthoracic echocardiography.

After induction of anesthesia, right IJV cannulation was attempted in the standard position with the insertion point at the apex of the triangle formed by the sternal and clavicular heads of sternocleidomastoid using triple lumen catheter set (Arrow, 7F) using Seldinger's technique.

In the first attempt, blood was freely aspirated at around 4 cm depth with the finder needle and the introducer needle. During insertion of the guide-wire mild resistance was felt at about the depth the guide-wire was expected to enter the vein. However, the senior resident (who had nearly 3 years of experience after postgraduation) doing the cannulation, managed to thread the guide-wire in, with minimal manipulation. Following dilation, the catheter was inserted over the guide-wire without any difficulty. Since a total of five operating rooms share a single ultrasound machine, it was not available for immediate use at that point of time. It was decided to fix the catheter at 10 cm, but blood could be aspirated from only one side port of the triple lumen. Withdrawing the catheter did not help, and the guide-wire was inserted and the catheter once again advanced. Free flow of blood was not obtained even with this, and the catheter was removed and pressure applied.

The landmark was re-identified, and the finder needle inserted. The initial attempt was unsuccessful, and the angle of the needle was reduced. Blood was aspirated at the same depth as in the previous attempt, and free flow was observed. After passing the guide-wire freely, dilation of the vein was done with the dilator. The catheter was passed again to 10 cm and blood could be aspirated from only one lumen, this time from the distal one. A small amount of saline was pushed through the other lumens, and there was no resistance. Again misplacement of the central venous catheter was suspected, and the subsequently catheter was removed and the pressure was applied at the insertion site. A more medial point of entry was chosen (medial to the sternal head of sternocleidomastoid).[36] The cannulation was done this time without difficulty. All the three lumens were patented this time as evident by free aspiration of blood. No swelling was found above the clavicle. The patient was hemodynamically stable, and the surgery proceeded. Before going on bypass after heparinization, the only thing noted was a slightly lower blood pressure (BP) of 90/50 mm Hg and a relatively low central venous pressure (CVP) of 3–4 cm of H2O.

Relative hypotension was ensured at the time of aortic cannulation to prevent dissection of the aorta which is possible in Marfan's syndrome. Operating surgeon was able to trace the tip of the catheter inside superior vena cava (SVC) during CPB. On weaning from bypass, after removing the SVC cannula, it was noticed that the medial portion of the right side pleura was bulging into the operating field. Initially, seepage of blood into the pleura from the operating field was suspected, and pleura was opened. About 1.5 L of clots and blood was removed. At this point, the BP fell suddenly from 90 to 50 systolic. A single, 2 mm tear in the right subclavian vein at the portion where it crosses the apex of the lung was noticed.

The tear was sutured in about 10 min and the BP improved. Adequate replacement of packed red cells was done, and the patient was separated from bypass uneventfully. The postoperative course was uneventful.

DISCUSSION

Subclavian vessel injury is a potentially dangerous complication of IJV cannulation which can end fatally. Most of the serious incidents involve the artery.[12345] Injury to the right brachiocephalic vein[567] and SVC have been also been reported. This report described significant hemothorax due to subclavian vein injury during central venous cannulation prior to initiation of surgery, leading to hemodynamic decompensation while weaning from CPB.

We presume that the needle was directed more laterally and inserted too deep so that the subclavian vein was entered directly. After passing the guide-wire into the vein, the dilator was introduced to dilate the proximal wall of the vein. Apparently, the dilator pierced the proximal wall and with further advancement, it came out from the distal wall pushing the guide-wire sideways along with it.

To prevent such an injury, it is advised that if any resistance is met, the guide-wire should be moved to and fro inside the dilator to check if it is freely mobile.[58] However, it may not always be possible to appreciate the meager resistance offered by the vessel wall. The vessel walls may have been delicate in this case as the patient had Marfan's syndrome. However, if the vessel wall is breached and the guide-wire gains access into the pleural cavity, it would be possible to move the guide-wire freely inside the dilator. In our case, when the length of the catheter was adjusted, presumably one of the side ports was inside the vein, and the blood was aspirated. In the second attempt, we were able to aspirate blood from the distal lumen alone. One possibility could be that the catheter was inside the subclavian vein with the side ports outside the vein. The other possibility might be that the catheter entered the pleural cavity. The blood that was being aspirated could have been from the collection in the pleural cavity as the tear from the first attempt continued to bleed. However, since there was no accompanying pneumothorax, we assume that the introducer needle did not enter the pleural cavity.

An injury caused by an introducer needle might seal by itself. But if the vessel wall is dilated with a dilator, the breach left is large and circular and does not close easily. It may continue to bleed even after inserting the catheter as one can imagine, the injury caused is more severe if the dilator comes out through the distal wall along with the guide-wire as we presume occurred in our case. The defect created in this case is larger than the diameter of dilator and actually tears the vessel as the dilator pushes through the wall along with the guide-wire. This is because the possibly stiffer guide-wire bends and forms a semicircle before coming out of the vessel lumen [Figure 1].

Figure 1

Dilator coming out through the distal wall along with the guide-wire

Since the subclavian vessels lie over the lung as they run behind the clavicle, an injury to these, especially on the inferior wall, can cause unrestricted bleeding into the pleural cavity. This may be the reason for the absence of any obvious hematoma above the clavicle. Significant bleeding had occurred before going on bypass as there was a large amount of clot in the blood that was evacuated. The CVP was also notably low despite resuscitation before bypass. When the bypass was initiated, the positive pressure ventilation was stopped. This potentially might have removed the tamponade effect offered by the expanded lung. Besides, heparinization could have worsened the bleeding as in a similar case reported by Innami et al.[2]

Several case reports have cautioned against the practice of advancing the dilator too far.[159] The dilator should not be inserted beyond the approximate depth that has been traversed by the introducer needle. This will ensure that the dilator traverses only up to the proximal entry of the guide-wire into the vein. This will achieve dilation of the skin, subcutaneous tissue and the entry of the guide-wire into the vein. When the dilator is inserted beyond this point, injury to the posterior wall of the vein becomes a possibility. Ultrasound can give localization of entry points of needle only.[10] The course of catheter or guide-wire can be appreciated only up to very short distance.[1011] The use of ultrasound may not offer foolproof protection against this mishap. The ultrasound image is distorted as the skin, and the subcutaneous tissue are stretched by the advancing dilator.

The subclavian vessels are entered during IJV cannulation when the needle is directed more laterally. Often this extreme angulation is adopted to avoid injury to the carotid artery or to a medially located lung apex. While hunting for the vein, the tendency to advance the needle too deep should be resisted. The needle should not be passed deeper than the estimated depth to the clavicle.[8] One suggestion to avoid this would be to insert the needle at an angle of 60° or more to the skin in the coronal plane as opposed to the widely recommended 45°. This ensures that the vein is entered higher in the neck and at a smaller depth.[12] At this angle, it is less likely to encounter pleura or the subclavian vessels even if the needle is passed deep. However, the guide-wire can sometimes hitch against the posterior wall of the vein and cause difficulty in advancing it into the vein. If this occurs, reducing the angle, most of the time, easily negotiates the guide-wire.[1213]

CONCLUSION

Subclavian vein tear during central venous cannulation is often a fatal complication. Early diagnosis and intervention are of paramount important. Use of ultrasound to estimate the depth of penetration of the needle, the position of the tip of the needle, and the position of the guide-wire could help to avoid this type of complication. However, in spite of these measures, complications can still occur. The dilator should not be inserted beyond the approximate depth that has been traversed by the introducer needle. Dilator traverses only up to the proximal entry of the guide-wire into the vein. Measuring the depth (IJV - skin distance) by ultrasonography (USG), dilation of the skin, subcutaneous tissue and the USG finding of entry of the guide-wire into the vein will further decrease complications during IJV cannulation. To avoid such type incident in futures, we have also taken certain important measure to improve the clinical standard of care in our institute. This includes the use of ultrasound for central venous cannulation, supervision of senior anesthesiologist during the procedures and good communication between surgeons, anesthesiologist and perfusionist throughout procedures.

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Conflicts of interest

There are no conflicts of interest.