Matthew M. Nalbandian

Superior maturation and patency of primary brachiocephalic and transposed basilic vein arteriovenous fistulae in patients with diabetes

PURPOSE Primary radiocephalic arteriovenous fistulas (RCAVFs) have classically been used for the initiation of dialysis. If a suitable forearm cephalic vein can be demonstrated, it is used to construct such a fistula. However, we have noted a tendency for RCAVF in patients with a history of diabetes mellitus (type I and type II) to remain patent but not mature to the point of cannulation. Therefore, the present study was undertaken. METHODS Fifty-eight consecutive patients with diabetes who required initial access for hemodialysis at an urban medical center and tertiary Veterans Medical Center underwent creation of an RCAVF (n = 10), brachiocephalic arteriovenous fistula (BCAVF; n = 22), or transposed basilic vein arteriovenous fistula (TBAVF; n = 26). The vein used was determined by physical examination with tourniquet compression. If neither forearm or upper-arm cephalic veins were 2 mm in diameter, a TBAVF was created after venography. Patency was determined by Kaplan-Meier estimate; differences between groups were assessed by Fishers exact test. RESULTS The 70% rate of nonmaturation of RCAVFs was significantly greater than the 27% rate for BCAVFs and 0% for TBAVFs (p < 0.05). The 33% cumulative primary patency rate at 18 months for RCAVFs was significantly less than 78% for BCAVFs and 79% for TBAVFs (p < 0.001). Within and between groups, there were no significant differences in age, gender, aspirin use, history of congestive heart failure, erythropoietin use, hematocrit level, history of peripheral vascular disease, or mortality rate. CONCLUSIONS In patients with renal failure and a history of diabetes, both primary BCAVFs and TBAVFs demonstrate significantly greater maturation and increased primary cumulative patency rates compared with RCAVFs; therefore, these autogenous conduits are considered to be optimal in this group of patients. Whether the discrepancy in lower-arm vein maturation is a result of a lack of compensatory increase in radial arterial flow or an intrinsic defect in the lower-arm cephalic vein is currently under investigation.

Perioperative outcomes of anterior lumbar surgery in obese versus non-obese patients

BACKGROUND CONTEXT Anterior lumbar surgery is a common procedure for anterior lumbar interbody fusion and disc replacement but the impact of obesity on this procedure has not been determined. PURPOSE To assess the perioperative outcomes of anterior retroperitoneal lumbar surgery in obese versus non-obese patients. STUDY DESIGN/SETTING Prospective review of patients with anterior retroperitoneal lumbar disc procedures PATIENT SAMPLE Seventy-four patients with anterior retroperitoneal lumbar disc procedures performed were evaluated. OUTCOME MEASURES Access-related parameters included tissue depth (skin-to-fascia and fascia-to-spine depths), length of incision, estimated blood loss during the anterior procedure, the duration of the anterior exposure, and the duration of the entire anterior procedure. Outcome measures included complications attributable to the anterior procedure, analgesic use, length of time to ambulation, and length of hospitalization. METHODS Seventy-four anterior retroperitoneal lumbar disc procedures were prospectively analyzed. Patient age, sex, body mass index, comorbidities, diagnosis, and operative parameters were collected. Access-related parameters and outcome measures were compared between obese and non-obese patients. Obesity was defined as body mass index greater than or equal to 30. RESULTS There were 35 males and 39 females. Mean age was 46.6 years. The main diagnosis (63.5%) was discogenic back pain. Forty-one (55%) patients were non-obese and 33 were obese. The two patient groups were comparable in terms of age, sex, diagnosis, mean number of anterior levels operated, and previous abdominal surgery (all p>.05). In obese patients, there were two iliac vein lacerations (major complication rate, 6.1%), one superficial infection, and one urinary tract infection (minor complication rate, 6.1%). In non-obese patients, there were two iliac vein lacerations, one intestinal serosal tear (major complication rate, 7.3%), and two urinary tract infections (minor complication rate, 4.9%). There was no significant difference in the complication rates between obese and non-obese patients (p=.6). Obese patients have significantly longer duration of anterior exposure, duration of entire anterior surgery, longer length of anterior incision, and more depth from skin to fascia and from fascia to spine compared with non-obese patients. However, obesity does not affect blood loss, analgesic use, length of time to ambulation, and length of hospitalization. CONCLUSION Perioperative outcomes in obese and non-obese patients were comparable and obesity is not related to an increased risk of morbidity in anterior lumbar surgery.

Successful limb reperfusion using prolonged intravascular shunting in a case of an unstable trauma patient: A case report

When peripheral vascular injuries present in conjunction with life threatening emergencies, controlling hemorrhage from a peripheral blood vessel may take initial priority, however, sacrificing a limb to preserve life is a well-established dictum. The use of intravascular shunts has allowed arterial and venous injuries to be controlled and temporized while treating other injuries. Typically, intravascular shunts are used for short time periods while orthopedic injuries are repaired or other life threatening injuries are managed. The following case demonstrates the long-term use of an intravascular arterial shunt to treat a traumatic transection of the common femoral artery and vein in a patient with an open pelvic fracture from blunt trauma. A 20-year-old woman fell between a subway platform and an oncoming train. She sustained a crush injury to her lower extremity and pelvis as she was pinned between the train and platform. The patient presented with active hemorrhage from a groin laceration, quickly became hemodynamically unstable, and was brought to the operating room. In addition to a pelvic fracture with massive pelvic hematoma she sustained a complete transection of the bifurcation of the common femoral artery (CFA), the common femoral vein (CFV), and associated orthopedic injuries. Vascular shunts were placed in the common femoral artery and vein. The patient became hypotensive from an expanding retroperitoneal hematoma. Pelvic bleeding was controlled with angioembolization and the venous injury was repaired. At this time the patient became cold, acidotic, and coagulopathic. It was thought unsafe to proceed with the arterial repair and it was elected to keep her arterial shunts in place and perform a planned reexploration in 24 hours after correcting her physiologic status. The patient returned to the operating room for an elective repair of her CFA the following day. Her shunt had remained patent throughout this time. She underwent a reverse saphenous vein graft from her CFA to her SFA. After a prolonged hospital course she was ultimately transferred to a rehabilitation center with intact pulses in both lower extremities. This case demonstrates the effectiveness of prolonged (>6 hours) use of an intravascular shunt as part of damage control surgery for peripheral arterial and venous injuries. In a patient who would otherwise undergo an amputation for their injury, the risk of shunt thrombosis, or infection, during damage control resuscitation may not be a contraindication for placement.

Variations in the iliolumbar vein during the anterior approach for spinal procedures.

Study Design. Retrospective study from data from a single access surgeon at 2 hospitals. Objective. To increase the surgeons awareness of iliolumbar vein (ILV) variants during the anterior approach to the lumbar spine. Summary of Background Data. Although there are many advantages to using the anterior approach, serious risks are involved, namely, vascular injury. The ILV is especially vulnerable when exposing the L4 and L5 vertebrae, and its ligature is recommended to avoid massive hemorrhage from its disruption. Cadaver studies on ILV variants have mainly analyzed drainage patterns. To our knowledge, however, no studies on ILV variants have been conducted on live humans during anterior spinal surgical procedures. Methods. A total of 159 patients who underwent anterior spinal surgery of at least the L4–L5 levels were included. Cases not involving the L4–L5 level were excluded. Frequency of anomalous ILVs and their possible association with diagnosis (spondylolisthesis, herniated nucleus pulposus, degenerative disc disease, and stenosis), sex, comorbidities, and pelvic history was evaluated. ILV was classified into 5 types: type 0 (missing ILV), type 1 (single ILV), type 2 (2 ILVs), type 3 (3 ILVs), and type 4 (>3 ILVs). Results. Most patients had a single ILV (73%, N = 116). Multiple ILVs were found in 25.8% of cases: 27 cases (17%) for type 2, 11 cases (6.9%) for type 3, and 3 cases (1.9%) for type 4. A higher frequency of multiple ILVs was found in males (32%) than in females (19.2%) (P = 0.034). Diagnosis, comorbidity, and pelvic surgical history were not associated with the number of ILVs. Conclusion. The high frequency of multiple ILVs found during the anterior approach is crucial knowledge for access surgeons, as it will help them anticipate such anomalies and thus avoid the potentially catastrophic complications of an avulsion of an unexpected extra vein. Level of Evidence: 2

Successful management of carotid stenosis in a high-risk population at an inner-city hospital.

This is a retrospective review of all carotid endarterectomies (CEA) (n=91) done from 1993 to 2002 at an inner-city hospital (Group I). This group was compared to a randomly selected group of patients (n= 445) treated at a private hospital (Group II). The same high-volume surgeons performed CEAs at both hospitals. The majority of Group I patients (71.4%) were members of racial minority groups. They were also more likely to be younger (p<0.001), hypertensive (p< 0.03), diabetic (p< 0.001), and current smokers (p< 0.001); have contralateral carotid artery occlusion (p=0.04); and present with stroke (p<0.001) than Group II patients. Despite this, the incidence of postoperative myocardial infarction (2.2% vs 0.2%, p= 0.08), stroke (1.1% vs 1.6%, NS), and death (1.1% vs 0%, NS) was comparable between the 2 groups. Aggressive preoperative workup for occult cardiac disease in Group I revealed an incidence of 25.9% (n=15). Of these, 5 (33.3%) were found to have coronary artery disease severe enough to warrant intervention before CEA. In an inner-city population with increased medical comorbidities, more severe cerebrovascular disease, and relatively low volume of carotid surgery, the results of CEA were comparable to those in patients treated at a high-volume private hospital. The presence of high-volume surgeons, operating at the low-volume municipal hospital, may contribute to the low complication rate. Finally, aggressive preoperative cardiac workup in this underserved population revealed a meaningful incidence of occult coronary artery disease requiring intervention before CEA.