S100B concentrations increase perioperatively in jugular vein blood despite limited metabolic and inflammatory response to clinically uneventful carotid endarterectomy.

BACKGROUND: Our aim was to test the hypothesis that metabolic and inflammatory responses of the brain perioperatively during carotid endarterectomy (CEA) might affect blood brain barrier (BBB) integrity. METHODS: Twenty patients with >70% stenosis of internal carotid artery (ICA) were prospectively included. Surgery was performed under general anaesthesia. Blood was sampled from ipsilateral internal jugular vein and radial artery: just before, during, and after ICA clamping S100B protein, glucose, lactate, 20 amino acids, and key cytokines were analysed. RESULTS: Jugular vein S100B increased during clamping and reperfusion, while a marginal systemic increase was recorded, unrelated to stump pressure during clamping. Glucose increased during clamping in jugular vein blood and even more systemically, while jugular lactate values were higher than systemic values initially. Most amino acids did not differ significantly between jugular vein and systemic levels: glutamic acid and aspartic acid decreased during surgery while asparagine increased. Jugular vein interleukin (IL)-6 showed a transient non-significant increase during clamping and decreased systemically. IL-8 and IL-10 increased over time. CONCLUSIONS: Rising jugular vein S100B concentrations indicated reduced BBB integrity, and marginal secondary increase of S100B systemically. Limited ischaemic effects on the brain during cross-clamping, unrelated to S100B concentrations, were confirmed by lower brain glucose levels and higher lactate levels than in systemic blood. The lack of increased jugular vein glutamic acid disproves any major ischaemic brain injury following CEA. The inflammatory response was limited, did not differ greatly between jugular and systemic blood, and was unrelated to S100B.

Limb ischemia after EVAR: an effect of the obstructing introducer?

PURPOSE: To evaluate the splanchnic and limb metabolic effects of open repair (OR) of abdominal aortic aneurysms (AAA) versus endovascular aneurysm repair (EVAR) in a pilot study utilizing microdialysis. METHODS: Nine AAA patients (8 men; mean age 74 years, range 61-85) were treated with EVAR and 9 had an OR (5 men; mean age 70 years, range 55-85). In the EVAR cases, which were performed percutaneously, the external iliac artery was obstructed by the introducer to a mean functional stenosis of 70% (52%-100%). Catheters for microdialysis were placed subcutaneously above the ankle of the right leg and freely in the abdominal cavity to measure the levels of lactate and pyruvate. The lactate/pyruvate ratio was calculated as a measure of ischemia. Measurements started at the end of surgery and continued for 2 days. Mean values were compared using the Mann-Whitney U test. RESULTS: The mean value of intraperitoneal lactate during the first day after EVAR was 1.5+/-0.7 mM versus 2.6+/-0.8 mM after OR (p = 0.019). The lactate/pyruvate ratio was 10.2+/-2.2 after EVAR and 12.3+/-2.6 after OR (p = 0.113). Leg lactate mean values were 4.2+/-2.0 mM after EVAR versus 1.8+/-0.6 mM after OR (p<0.001). The lactate/pyruvate ratio was 20.1+/-8.3 for EVAR and 13.7+/-3.3 for OR (p = 0.040). These differences between EVAR and OR continued for the second day. CONCLUSION: Intraperitoneally, metabolism was slightly increased after OR; however, it was not suggestive of splanchnic ischemia. Leg findings reflected a more extensive ischemia after EVAR over 48 hours, which was a somewhat unexpected finding that may be related to the introducer's impact on blood flow to the limb during the intervention. Although no clinical consequences were recorded, the finding suggests some benefit of minimizing as much as possible the time of reduced perfusion to the limb.

Iliofemoral venous pressure correlates with intraabdominal pressure in morbidly obese patients.

Clinically, it has been observed that severely and morbidly obese individuals more often have venous leg symptoms related to venous stasis than normal-weight persons have. Obesity is associated with an increased intraabdominal pressure (IAP). The increased IAP in severely and morbidly obese patients would reasonably cause an elevated iliofemoral venous pressure (IFVP), which transmits via incompetent femoral veins, causing venous stasis in the lower limbs. The aim of this study was to determine whether the elevated IAP assessed by the urinary bladder pressure (UBP) corresponded with an increased directly measured IFVP. Fifteen women with morbid obesity were investigated with simultaneous UBP and direct iliofemoral vein pressures. Four normal-weight controls were investigated in the same manner. The obese patients had significantly higher UBP than the controls had, 19.1 and 8.5 cm H2O, respectively. They also had elevated IFVP compared with the controls, 19.7 and 7.5 cm H2O, respectively, and these IFVPs correlated well with the UBPs. The assumption that increased IAP in morbidly obese patients causes increased IFVP was consequently determined. To our knowledge, this has not previously been demonstrated in human individuals. How these elevated pressures contribute to the development of lower limb venous insufficiency is subject to further studies.

Reflux from thigh to calf, the major pathology in chronic venous ulcer disease: surgery indicated in the majority of patients.

The aim of this study was to define the underlying anatomical and pathophysiological conditions in limbs with venous ulcers in order to get information for the most appropriate treatment selection. Ninety-eight limbs (83 patients, 59 men), with active chronic venous ulcers, were analyzed retrospectively and classified according to the CEAP (clinical, etiological, anatomical, and pathophysiological) classification. Duplex-ultrasound was performed in all patients, while air-plethysmography and venography were performed selectively on potential candidates for deep venous reconstruction. Sixty-six ulcers were primary in origin and 32 were secondary. Reflux was present in all limbs except 1. Isolated reflux in 1 system (superficial = 3, deep = 4, perforator = 3) was seen in 10 legs (10%), while incompetence in all 3 systems was seen in 51 legs (52%). Superficial reflux with or without involvement of other systems was seen in 84 legs (86%), 72 legs (73%) had deep reflux with or without involvement of other systems, and incompetent perforator veins were identified in 79 limbs (81%). Axial reflux (continuous reverse flow from the groin region to below knee) was found in 77 limbs (79%). The femoral vein was the single most common deep venous segment in which either reflux or obstruction was found. Axial distribution of disease was found in the majority of cases and no patient had isolated deep venous incompetence below knee. Primary disease was the predominant etiologic cause and reflux was the main pathophysiological finding. Practically all patients were found to have 1 or more sites of reflux or obstruction that could benefit from operative treatment.

Salvage of an acutely ruptured thoracic aortic aneurysm during CPR.

PURPOSE: To report the successful endovascular treatment of a ruptured thoracic aortic aneurysm during cardiopulmonary resuscitation. CASE REPORT: A 72-year-old woman with a type B aortic dissection treated conservatively for 8 years was referred for rupture of a 16-cm aneurysm of the descending thoracic aorta. During transfer to the operating room, the patient suffered cardiac arrest; cardiopulmonary resuscitation (CPR) was initiated. A few minutes later during CPR, the surgical procedure began with a cutdown of the right femoral artery and insertion of a guidewire and an aortic occlusion balloon, which was inflated at the origin of the left subclavian artery (LSA). Blood pressure was immediately measurable. By only partially deflating the occluding balloon, a thoracic stent-graft was advanced above it and deployed at the origin of the LSA while rapidly deflating and retracting the occluding balloon. Three stent-grafts were required to cover 27 cm of the descending aorta. The patient was partly ventilator dependent for 3 months due to a massive pleural hematoma that was not evacuated. At the 10-month follow-up, the patient is fully recovered without any sign of respiratory dysfunction or any other sequela. CT scans reveal that the massive hematoma is almost completely resolved. CONCLUSIONS: This case illustrates that optimal collaboration between anesthesiologists, interventional radiologists, and vascular surgeons with appropriate resources can significantly expand the possibilities of emergent treatment in the face of aortic rupture.

Could prolonged air travel be casually associated with subclavian vein thrombosis.

BACKGROUND: Air travel associated with venous thromboembolism has recently achieved public awareness due to intense media coverage. The interest has focused on deep vein thrombosis (DVT) of the lower limbs with pulmonary embolism. The World Health Organization (WHO) is planning several international multicenter trials to study the problem and, if it exists, try to find a means for prevention. METHODS: This is a case presentation of acute venous thromboembolism of the upper limbs associated with long-haul flights. Five patients were admitted to Straub Hospital in Honolulu after 5 to 10 hours flight. RESULTS: Patient 1 had a previous shoulder injury with DVT; patient 2 had chronic atrial fibrillation; patients 3 and 5 had clavicular fractures; and patient 4 had a subclavian vein compression. CONCLUSION: It is not possible to draw any conclusions about the association between air flights and subclavian vein thrombosis from this small retrospective case study. Our objective was to indicate the possibility of such a relationship.