Design, optimisation and standardisation of a high-dimensional spectral flow cytometry workflow assessing T-cell immunophenotype in patients with melanoma

Objectives

Despite the success of immune checkpoint blockade, most metastatic melanoma patients fail to respond to therapy or experience severe toxicity. Assessment of biomarkers and immunophenotypes before or early into treatment will help to understand favourable responses and improve therapeutic outcomes.

Methods

We present a high-dimensional approach for blood T-cell profiling using three multi-parameter cytometry panels: (1) a TruCount panel for absolute cell counts, (2) a 27-colour spectral panel assessing T-cell markers and (3) a 20-colour spectral panel evaluating intracellular cytokine expression. Pre-treatment blood mononuclear cells from patients and healthy controls were cryopreserved before staining across 11 batches. Batch effects were tracked using a single-donor control and the suitability of normalisation was assessed. The data were analysed using manual gating and high-dimensional strategies.

Results

Batch-to-batch variation was minimal, as demonstrated by the dimensionality reduction of batch-control samples, and normalisation did not improve manual or high-dimensional analysis. Application of the workflow demonstrated the capacity of the panels and showed that patients had fewer lymphocytes than controls (P = 0.0027), due to lower naive CD4+ (P = 0.015) and CD8+ (P = 0.011) T cells and follicular helper T cells (P = 0.00076). Patients showed trends for higher proportions of Ki67 and IL-2-expressing cells within CD4+ and CD8+ memory subsets, and increased CD57 and EOMES expression within TCRγδ+ T cells.

Conclusion

Our optimised high-parameter spectral cytometry approach provided in-depth profiling of blood T cells and found differences in patient immunophenotype at baseline. The robustness of our workflow, as demonstrated by minimal batch effects, makes this approach highly suitable for the longitudinal evaluation of immunotherapy effects.

Broad and ultra-potent cross-clade neutralization of HIV-1 by a vaccine-induced CD4 binding site bovine antibody

Human immunodeficiency virus type 1 (HIV-1) vaccination of cows has elicited broadly neutralizing antibodies (bNAbs). In this study, monoclonal antibodies (mAbs) are isolated from a clade A (KNH1144 and BG505) vaccinated cow using a heterologous clade B antigen (AD8). CD4 binding site (CD4bs) bNAb (MEL-1872) is more potent than a majority of CD4bs bNAbs isolated so far. MEL-1872 mAb with CDRH3 of 57 amino acids shows more potency (geometric mean half-maximal inhibitory concentration [IC₅₀]: 0.009 μg/mL; breadth: 66%) than VRC01 against clade B viruses (29-fold) and than CHO1-31 against tested clade A viruses (21-fold). It also shows more breadth and potency than NC-Cow1, the only other reported anti-HIV-1 bovine bNAb, which has 60% breadth with geometric mean IC₅₀ of 0.090 μg/mL in this study. Using successive different stable-structured SOSIP trimers in bovines can elicit bNAbs focusing on epitopes ubiquitous across subtypes. Furthermore, the cross-clade selection strategy also results in ultra-potent bNAbs.

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Sequential vaccine with different SOSIP trimers could elicit bNAbs

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Cross-clade B-cell-sorting probe could select ultra-potent bNAbs

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Bovine CD4bs monoclonal antibody neutralizes HIV-1 isolates potently

A new method for post-translationally labeling proteins in live cells for fluorescence imaging and tracking

We present a novel method to fluorescently label proteins, post-translationally, within live Saccharomycescerevisiae. The premise underlying this work is that fluorescent protein (FP) tags are less disruptive to normal processing and function when they are attached post-translationally, because target proteins are allowed to fold properly and reach their final subcellular location before being labeled. We accomplish this post-translational labeling by expressing the target protein fused to a short peptide tag (SpyTag), which is then covalently labeled in situ by controlled expression of an open isopeptide domain (SpyoIPD, a more stable derivative of the SpyCatcher protein) fused to an FP. The formation of a covalent bond between SpyTag and SpyoIPD attaches the FP to the target protein. We demonstrate the general applicability of this strategy by labeling several yeast proteins. Importantly, we show that labeling the membrane protein Pma1 in this manner avoids the mislocalization and growth impairment that occur when Pma1 is genetically fused to an FP. We also demonstrate that this strategy enables a novel approach to spatiotemporal tracking in single cells and we develop a Bayesian analysis to determine the protein's turnover time from such data.

Resistance to HSP90 inhibition involving loss of MCL1 addiction

Inhibition of the chaperone heat-shock protein 90 (HSP90) induces apoptosis, and it is a promising anti-cancer strategy. The mechanisms underpinning apoptosis activation following HSP90 inhibition and how they are modified during acquired drug resistance are unknown. We show for the first time that, to induce apoptosis, HSP90 inhibition requires the cooperation of multi BH3-only proteins (BID, BIK, PUMA) and the reciprocal suppression of the pro-survival BCL-2 family member MCL1, which occurs via inhibition of STAT5A. A subset of tumour cell lines exhibit dependence on MCL1 expression for survival and this dependence is also associated with tumour response to HSP90 inhibition. In the acquired resistance setting, MCL1 suppression in response to HSP90 inhibitors is maintained; however, a switch in MCL1 dependence occurs. This can be exploited by the BH3 peptidomimetic ABT737, through non-BCL-2-dependent synthetic lethality.

Prevalence and correlates of exchanging sex for drugs or money among adolescents in the United States

OBJECTIVE

This study examined the prevalence and correlates of exchanging sex for drugs or money among a nationally representative sample of 13,294 adolescents in the United States.

METHODS

Data are from the National Longitudinal Study of Adolescent Health, waves I and II. The lifetime prevalence of exchanging sex was estimated and a cross sectional analysis of sociodemographic and behavioural correlates was conducted. Unadjusted odds ratios were obtained.

RESULTS

3.5% of adolescents had ever exchanged sex for drugs or money. Two thirds of these youths were boys. The odds of having exchanged sex were higher for youths who had used drugs, had run away from home, were depressed, and had engaged in various sexual risk behaviours. 15% of boys and 20% of girls who had exchanged sex reported they had ever been told they have HIV or another sexually transmitted infection (STI).

CONCLUSIONS

Adolescents with a history of exchanging sex have engaged in other high risk behaviours and may experience poor health outcomes, including depression and HIV/STIs. These findings should help inform strategies to prevent this high risk sexual behaviour and its potential consequences.

An audit of the accuracy of fine needle aspiration using a liquid-based cytology system in the setting of a rapid access breast clinic

We have assessed the effectiveness and accuracy of reporting fine needle aspirates of the breast (FNAB) using a liquid-based cytology (LBC) system (the Cytospin) method) in the pressure situation of a rapid access clinic (RAC). We have reviewed every case from the RAC from June 1997 to February 2001 inclusive. There were 1322 cases, which accounted for 26% of the total FNAB received in our department over the period. There were 323 cancers and 999 benign cases in the group. The inadequate/nondiagnostic rate (C1) was 18%. The absolute sensitivity, including C1 cases, was 73% with the complete sensitivity being 90%. The groups of 'atypical, probably benign' (C3) and 'suspicious, probably malignant' (C4) accounted for a total of 6.2%. There were 28 false negative cases and 1 false positive case (a borderline phyllodes tumour). Comparing our results with the standards recommended by the NHSBSP has shown that the diagnosis of FNAB using this LBC method is feasible, accurate and reliable even in the pressure situation of a RAC.

Borderline nuclear change; can a subgroup be identified which is suspicious of high-grade cervical intraepithelial neoplasia, i e CIN 2 or worse?

Borderline nuclear change; can a subgroup be identified which is suspicious of high-grade cervical intraepithelial neoplasia, i.e. CIN 2 or worse? Only 10% of first borderline smears are associated with a histological high-grade (HG) abnormality, i.e. CIN 2,3, invasive malignancy or glandular neoplasia on subsequent investigation. The advantages of highlighting this subgroup are obvious but is this possible? From 1996 and 1997, 242 borderline smears with histological follow-up were examined by two independent experienced observers (observer 1 and 2) without prior knowledge of further investigation results. For each smear a profile of nuclear details was produced, also noting the type of cell mainly affected by the process; then the observers were asked to assess the degree of worry of HG disease for each smear i.e. whether the smear fell into group 1 borderline changes indicative of low-grade (normal, inflammatory, CIN1/HPV) disease (BL/LG) or group 2 difficult borderline smear, HG disease (CIN 2,3, invasive neoplasia or glandular neoplasia) cannot be excluded (BL/HG). Observer 1 selected a group of BL/HG with a PPV for HG disease of 38%, with observer 2 having a PPV of 50%; this compared with the overall laboratory HG disease PPV for borderline smears of 14%. Both observers found the most useful criterion to be the increase in nuclear:cytoplasmic ratio. Our results show that it is possible to separate a small group of borderline smears which should be classified as 'borderline/high grade lesion difficult to exclude' (BL/HG). Both observers had some success in arriving at this classification although their method of selecting out this group was quite different.

Long-term functional outcome of neurogenic thoracic outlet syndrome in surgically and conservatively treated patients

PURPOSE

Neurogenic thoracic outlet syndrome (NTOS) in the absence of bony and electrodiagnostic abnormalities, often referred to as disputed NTOS, remains enigmatic. Optimal treatment, especially the role of surgery, is controversial. The long-term functional outcome of a cohort of patients undergoing independent medical examination for disputed NTOS with symptoms sufficiently severe to cause inability to work forms the basis for this report.

METHODS

Patients with disputed NTOS and symptoms sufficiently severe to cause at least temporary inability to work seen for independent medical examinations from 1990-1998 formed the study group. None of the patients were treated by our group. Functional outcome was assessed with information from a standardized telephone interview or patient questionnaire. The patients' ability to return to work and an assessment of their current level of symptoms and symptom progression since the time of onset were determined.

RESULTS

Seventy-nine patients were reevaluated at a mean follow-up of 4.2 years (range, 2-7.5 years) after our initial evaluation. Fifteen patients (19%) underwent first rib resection surgery performed by others, whereas 64 (81%) had no surgery. Patients undergoing surgery had missed more work time than those undergoing conservative management (27.6 +/- 6.0 months vs 14.9 +/- 2.6 months, P <.04). Return to work was achieved in nine patients who were operated on (60%) and in 50 patients who were not operated on (78%) (P = not significant [NS]). Among operated patients, current assessment of symptom severity was severe, moderate, mild, and asymptomatic in 7%, 47%, 40% and 7%, respectively. This distribution did not differ significantly from that observed in nonoperated patients (11%, 55%, 30%, 5%; P = NS). When asked about changes in symptomatic status since onset, 7% of the operated group had complete resolution, 27% had marked improvement, 40% had minimal improvement, 13% had no improvement, and 13% were worse. This did not differ significantly from the change in symptoms reported by the nonoperated group (2%, 30%, 22%, 31%, 16%; P = NS).

CONCLUSION

Most patients with disputed NTOS in this nonrandomized series were able to return to work and demonstrated an improvement of symptoms with long-term follow-up. First rib resection did not improve functional outcome in this group.

Quantitative assessment of fetal ventricular function: establishing normal values of the myocardial performance index in the fetus

OBJECTIVE

Assessment of ventricular function in the fetus has been limited for many reasons, including relative cardiac size and atypical orientation of fetal cardiac structures. A myocardial performance index (MPI) has been described in adult and pediatric populations as an echocardiographic measure of global (systolic and diastolic) ventricular performance. Because the MPI is a Doppler index, it is independent of ventricular geometry and can be applied to both left and right ventricular function. This study attempts to define the MPI in a group of normal fetuses and compare these data to other published studies of this index.

STUDY DESIGN

The right ventricular (RV) and left ventricular (LV) MPI were measured in 125 normal fetuses (20--40 weeks gestation, mean age 28 weeks). These fetuses were divided into five gestational age groups for comparison. These data were compared to 152 normal children (age 3--18 years, mean age 9.3 years).

RESULTS

In normal fetuses, the LV MPI was 0.36 +/- 0.06 and the RV MPI was 0.35 +/- 0.05. This was not statistically different from the group of normal children in whom the LV MPI was 0.35 +/- 0.03 and the RV MPI was 0.32 +/- 0.03. In addition, no significant change in the fetal MPI was seen with advancing gestational age.

CONCLUSION

This study demonstrates that fetal ventricular function can be quantitatively measured with the MPI. The MPI provides an easily obtainable and reproducible measure of fetal ventricular performance that can be readily incorporated into all fetal echocardiographic examinations.

Optimizing duplex follow-up in patients with an asymptomatic internal carotid artery stenosis of less than 60%

OBJECTIVES

The Asymptomatic Carotid Atherosclerosis Study established benefit of carotid endarterectomy for 60% to 99% asymptomatic internal carotid artery (ICA) stenosis. Optimal follow-up intervals to detect progression from < 60% to 60%-99% ICA stenosis are unknown. In a previous study from our laboratory, we found that ICAs with < 60% stenosis and peak systolic velocities (PSVs) of 175 cm/s or more on initial duplex were at high risk for progression. Prospective evaluation of this hypothesis and determination of optimal duplex follow-up intervals for asymptomatic patients with < 60% ICA stenosis form the basis of this report.

METHODS

All patients who underwent initial carotid duplex examination for any indication since January 1, 1995, with at least one patent, asymptomatic, previously nonoperated ICA with < 60% stenosis; with 6 months' or greater follow-up; and with one or more repeat duplex examinations were entered into the study. On the basis of the initial duplex examination, ICAs were classified into two groups: those with a PSV less than 175 cm/s and those with a PSV of 175 cm/s or more. Follow-up duplex examinations were performed at varying intervals to detect progression from < 60% to 60%-99% ICA stenosis with criteria previously reported (both PSV > or = 260 cm/s and end-diastolic velocity > or = 70 cm/s).

RESULTS

A total of 407 patients (640 asymptomatic ICAs with < 60% stenosis) underwent serial duplex scans (mean follow-up, 22 months). Three ICAs (0.5%) became symptomatic and progressed to 60%-99% ICA stenosis at a mean of 21 months (all transient ischemic attacks), whereas four other ICAs occluded without stroke during follow-up. Progression to 60%-99% stenosis without symptoms was detected in 46 ICAs (7%) (mean, 18 months). Of the 633 patent asymptomatic arteries, 548 ICAs (87%) had initial PSVs less than 175 cm/s, and 85 ICAs (13%) had initial PSVs of 175 cm/s or more. Asymptomatic progression to 60%-99% ICA stenosis occurred in 22 (26%) of 85 ICAs with initial PSVs of 175 cm/s or more, whereas 24 (4%) of 548 ICAs with initial PSVs less than 175 cm/s progressed (P <.0001). The Kaplan-Meier method was used to determine freedom from progression at 6 months, 12 months, and 24 months, which was 95%, 83%, and 70% for ICAs with initial PSVs of 175 cm/s or more versus 100%, 99%, and 95%, respectively, for ICAs with initial PSVs less than 175 cm/s (P <.0001).

CONCLUSIONS

Patients with < 60% ICA stenosis and PSVs of 175 cm/s or more on initial duplex examination are significantly more likely to progress asymptomatically to 60%-99% ICA stenosis, and progression is sufficiently frequent to warrant follow-up duplex studies at 6-month intervals. Patients with < 60% ICA stenosis and initial PSVs less than 175 cm/s may have follow-up duplex examinations safely deferred for 2 years.

Marjolin's ulcer presenting in the neck

'Marjolin's ulcer' is a term that has come to be used for epidermal squamous cell carcinomas that have developed in areas of chronic inflammation. To our knowledge this is the first ever report of a Marjolin's ulcer developing following long-term irritation of the skin of the neck. The history of the eponym is traced and reveals that Marjolin probably never actually described this pathological process.

Rapid growth in a cavernoma

The availability of magnetic resonance imaging has greatly increased the detection of cavernous malformations of the central nervous system in both symptomatic and asymptomatic patients. These lesions may be responsible for previously unexplained neurological events or may even have been incorrectly diagnosed. We describe a patient presenting with focal neurological signs in whom an initial diagnosis of malignant glioma had been made. Following excision, the pathological diagnosis was cavernoma. This vascular lesion has continued to show rapid growth and aggressive behaviour despite multiple surgical resections. The indications for operative and non-operative intervention will be discussed.

Controlled non-heart-beating donor liver transplantation: a successful single center experience, with topic update

BACKGROUND

The critical shortage of transplantable organs necessitates utilization of unconventional donors. We describe a successful experience of controlled non-heart-beating donor (NHBD) liver transplantation.

METHODS

Controlled NHBDs had catastrophic head injury, prognosis for no meaningful recovery, decision to withdraw life support, and subsequent consent for donation. After stopping mechanical ventilation in the operating room, death determination by a nontransplant caregiver, and rapid aortic cannulation, liver and kidneys were recovered.

RESULTS

Controlled NHBDs contributed 5% of hepatic allografts (8/164) from August 1996 through June 1999 (9% in 1998). Sixteen NHBDs afforded 8 livers and 24 kidneys. Liver donors (n=8) were 11-66 years old; half were >50 years old. Premortem alanine aminotransferase was 25-157 U/L. Arrest occurred 3-27 min after stopping ventilation. Perfusion started 3-5 min after incision, and <22 min after hypotension (mean arterial pressure: <50 mmHg). Patient and graft survivals are 100% at 18+/-12 months follow-up. There was no intraoperative complication, reperfusion syndrome, poor graft function, primary nonfunction, arterial thrombosis, biliary complication, or serious infection. Postoperative day 2 prothrombin time was 13+/-1 sec. Peak alanine aminotransferase was 980+/-601 U/L. Intensive care unit and posttransplant lengths of stay were 2+/-2 and 10+/-7 days, respectively. Soon after transplantation there was frequent temporary hyperbilirubinemia (five of eight recipients; bilirubin peak: 7-29 mg/dl, 2-3 weeks after transplantation) and rejection (4/8 recipients, <3 weeks after transplantation).

CONCLUSIONS

NHBDs significantly and safely expanded our donor pool. NHBD surgeons must be capable of rapid procurement. Cautious liberalization of criteria for accepting livers from NHBDs with confounding risk factors is justified. Refined ethics guidelines would broaden approval of NHBDs.

Neuroblastomatous recurrence of ganglioglioma. Case report

This case is believed to be the first reported recurrent intracranial ganglioglioma with purely neuroblastomatous malignant transformation. A complete macroscopic resection of a right frontal lobe tumor in an 18-year-old woman revealed differentiated ganglioglioma. Seven years later a large, well-demarcated recurrent tumor was again macroscopically totally resected in the same patient. Histological analysis showed malignant transformation in only the neuronal component of the original tumor. A review of the literature on recurrent gangliogliomas and their malignant transformation is included.

Patency and characteristics of lower extremity vein grafts requiring multiple revisions

OBJECTIVES

Multiple (> 1) revisions of lower extremity vein grafts may be required to maintain patency. Characteristics of recurrent lower extremity vein graft lesions and the patency achieved after multiple revisions have not been emphasized in reports on infrainguinal vein graft stenosis. This study was performed to determine (1) the patency of multiply revised lower extremity vein grafts and (2) the timing, location, and angiographic and duplex features of the recurrent lesions.

METHODS

Lower extremity vein grafts that were followed in a duplex surveillance protocol and required revisions from January 1990 through December 1998 were identified. All revisions were preceded by angiography. In multiply revised lower extremity vein grafts, the immediate preoperative angiogram and duplex examination findings, as well as the angiogram made before the previous revision and the duplex study done after the previous revision, were reviewed to characterize recurrent lesions at the time of previous and current graft revision. The patencies of grafts undergoing single and multiple revisions were compared.

RESULTS

A total of 233 lower extremity vein graft revisions were performed; of these, 50 (21%) were repeat revisions. Of grafts requiring more than one revision, 98% were normal on duplex examination after the initial revision. Five-year assisted primary patency of multiply revised grafts (91%) was not different from that of grafts with a single revision (89%; P not significant). Of 60 lesions repaired in the 50 repeat revisions, 29 (48%) were at the previously revised site, and 31 (52%) were at new sites. The time between revisions was less if the same site was revised (11 +/- 2 months) than if a different site required revision (20 +/- 4 months; P <.05). Arteriographic evidence of a minor (< 50% diameter) lesion was present at the time of the initial revision in 23% of cases in which revision of a second site was subsequently required.

CONCLUSION

In our experience, 21% of lower extremity vein grafts requiring initial revision ultimately require additional revisions. Multiply revised lower extremity vein grafts have excellent long-term patency. Lesions occur with equal frequency at the site of prior revision and new sites. Lesions prompting revision at new sites occur significantly later and are infrequently detected on prior imaging studies.

Revascularization of the superior mesenteric artery alone for treatment of intestinal ischemia

OBJECTIVE

Complete revascularization is recommended by many authors for treatment of intestinal ischemia. The observation that postprandial intestinal hyperemia is limited to the superior mesenteric artery (SMA) has suggested to us that SMA revascularization alone should be adequate treatment. We preferentially manage intestinal ischemia with a single bypass graft to the SMA and herein update our results using this approach.

METHODS

Patients were identified from a prospectively established vascular surgical registry. Each patient was assessed for acute versus chronic intestinal ischemia, preoperative angiographic findings, operation used, perioperative morbidity and mortality, late symptomatic relief, cause of death, and life table-determined survival and graft patency. Graft patency was determined by follow-up angiography or duplex scanning.

RESULTS

Fifty bypass grafts to the SMA alone were performed in 49 patients (31 women, 18 men; mean age, 62 years) for treatment of intestinal ischemia. In all patients additional splanchnic arteries were available for bypass grafting. Operative indications were acute symptoms in 21 patients, 14 of whom had bowel infarction; chronic symptoms in 26 patients; and prophylaxis in conjunction with infrarenal aortic surgery in 3 patients. Thirty-two grafts originated from the aorta or an iliac artery, and 18 originated from an aortic graft. There were 40 prosthetic and 10 autogenous conduits. Perioperative mortality was 3% in patients with chronic symptoms and 12% overall. All survivors were symptomatically improved. Mean follow-up was 44 months. Nine-year assisted primary graft patency was 79%, and 5-year patient survival was 61%. Two late deaths occurred in patients with recurrent intestinal ischemia resulting from graft occlusions.

CONCLUSIONS

Bypass grafting to the SMA alone appears to be both an effective and durable procedure for treatment of intestinal ischemia. Our results appear equal to those reported for "complete" revascularization for intestinal ischemia. When the SMA is a suitable recipient vessel, multiple bypass grafts to other splanchnic vessels are unnecessary in the treatment of intestinal ischemia.

Is a single preoperative duplex scan sufficient for planning bilateral carotid endarterectomy?

PURPOSE

Duplex scanning is often the sole imaging study before carotid endarterectomy (CEA). Patients with bilateral severe internal carotid artery (ICA) stenosis may be considered for bilateral CEA. High-grade ICA stenosis, however, may artifactually elevate velocity measurements used to quantify stenosis in the contralateral ICA. It is unknown whether ipsilateral CEA will influence duplex determination of the presence of a contralateral 60% to 99% ICA stenosis. This study was performed to determine whether a single preoperative duplex scan is sufficient to plan bilateral CEA.

METHODS

Preoperative and early postoperative carotid duplex scans in patients with bilateral ICA stenosis who underwent unilateral CEA were reviewed. Changes in duplex scans that determined stenosis in the ICA contralateral to the CEA were analyzed. Previously validated criteria used to determine 60% to 99% ICA stenosis were a peak systolic velocity (PSV) of 260 cm/sec or more combined with an end diastolic velocity (EDV) of 70 cm/sec or more.

RESULTS

Over an 8-year period, 460 patients underwent CEA; 107 patients (23.3%) had an asymptomatic 50% to 99% contralateral ICA stenosis by standard criteria (PSV, >125 cm/sec) and an early postoperative duplex scan examination. Of these 107 patients, 38 patients (35.5%) had duplex scan criteria for 60% to 99% contralateral ICA stenosis. In these 38 patients, there was a mean postoperative PSV decrease of 47.7 cm/sec (10.1%) and a mean EDV decrease of 36.0 cm/sec (19.3%) in the ICA contralateral to the CEA. Eight of 38 (21.1%) preoperative contralateral 60% to 99% ICA lesions were reclassified as less than 60% on postoperative duplex scanning. Six of 69 (8.7%) preoperative lesions of less than 60% were reclassified as 60% to 99% on postoperative duplex scan. These six preoperative examinations were all close to the criteria for 60% to 99% stenosis (mean PSV, 232.5 cm/sec; mean EDV, 62.5 cm/sec).

CONCLUSION

One-fifth of patients with apparent 60% to 99% contralateral ICA lesions before the operation have less than 60% stenosis when restudied with duplex scan after unilateral CEA. Lesions below but near the cutoff for 60% to 99% may be reclassified as 60% to 99% on the postoperative duplex scan. These findings mandate that when duplex scanning is used as the sole imaging modality before CEA, patients with severe bilateral carotid stenosis must have an additional carotid duplex examination before operation on the second side.

Hypothenar hammer syndrome: proposed etiology

PURPOSE

Finger ischemia caused by embolic occlusion of digital arteries originating from the palmar ulnar artery in a person repetitively striking objects with the heel of the hand has been termed hypothenar hammer syndrome (HHS). Previous reports have attributed the arterial pathology to traumatic injury to normal vessels. A large experience leads us to hypothesize that HHS results from trauma to intrinsically abnormal arteries.

METHODS

We reviewed the arteriography, histology, and clinical outcome of all patients treated for HHS in a university clinical research center study of hand ischemia, which prospectively enrolled more than 1300 subjects from 1971 to 1998.

RESULTS

Twenty-one men had HHS. All had occupational (mechanic, carpenter, etc) or avocational (woodworker) exposure to repetitive palmar trauma. All patients underwent upper-extremity and hand arteriography, unilateral in eight patients (38%) and bilateral in 13 patients (62%). By means of arteriogram, multiple digital artery occlusions were shown in the symptomatic hand, with either segmental ulnar artery occlusion in the palm or characteristic "corkscrew" elongation, with alternating stenoses and ectasia. Similar changes in the contralateral asymptomatic (and less traumatized) hand were shown by means of 12 of 13 bilateral arteriograms (92%). Twenty-one operations, consisting of segmental ulnar artery excision in the palm and vein grafting, were performed on 19 patients. Histology was compatible with fibromuscular dysplasia with superimposed trauma. Patency of arterial repairs at 2 years was 84%. One patient (5%) required amputative debridement of necrotic finger tips. No other tissue loss occurred. There have been no recurrences of ischemia in patients with patent bypass grafts.

CONCLUSION

To our knowledge, this is the largest reported group of HHS patients. The characteristic angiographic appearance, histologic findings, and striking incidence of bilateral abnormalities in patients with unilateral symptoms lead us to conclude that HHS occurs when persons with preexisting palmar ulnar artery fibrodysplasia experience repetitive palmar trauma. This revised theory for the etiology of HHS explains why HHS does not develop in most patients with repetitive palmar trauma.

Extrathoracic arterial grafts performed for carotid artery occlusive disease not amenable to endarterectomy

HYPOTHESIS

Extrathoracic cervical grafts are safe and provide long-lasting stroke prevention in patients with disease not amenable to standard carotid bifurcation endarterectomy.

DESIGN

Review of a prospectively maintained vascular surgical registry.

SETTING

Combined university and Department of Veterans Affairs vascular surgical service.

PARTICIPANTS

Patients requiring surgery for carotid atherosclerotic occlusive disease not amenable to endarterectomy from January 1988 to March 1998.

INTERVENTIONS

Carotid interposition grafting, subclavian-carotid bypass, or carotid-carotid bypass.

MAIN OUTCOME MEASURES

Perioperative stroke and death, and life-table determination of freedom from stroke, stroke-free survival, and graft patency.

RESULTS

Sixty patients (mean age, 65.8 years; range, 36-83) underwent cervically based carotid grafting. All had greater than 70% stenosis or occlusion of the innominate, common carotid, or internal carotid arteries, and 30 (50%) had undergone at least 1 previous ipsilateral carotid endarterectomy. Indication for operation was stroke or transient ischemic attack in 46 (77%) and asymptomatic high-grade stenosis in 14 (23%). Operative procedures included 31 (52%) carotid interposition grafts, 18 (30%) subclavian-carotid grafts, and 11 (18%) carotid-carotid grafts. Mean follow-up was 29 months (range, 1-117 months). Perioperative stroke rate was 5% (3/60) all in symptomatic patients, and there were no perioperative deaths. By life-table analysis, freedom from stroke was 92% at 1 and 5 years. Stroke-free survival was 90% at 1 year and 61% at 5 years. Primary graft patency was 94% at 1 year and 84% at 5 years, with assisted primary patency of 90% at 5 years.

CONCLUSION

Cervical carotid artery grafts for complicated or recurrent carotid atherosclerosis not amenable to endarterectomy are durable and provide excellent freedom from stroke with low perioperative morbidity and mortality.

Vascular surgery and the Internet: a poor source of patient-oriented information

OBJECTIVE

Increasing numbers of patients use the Internet to obtain medical information. The Internet is easily accessible, but available information is under no guidelines or regulations. We sought to evaluate the type, quality, and focus of vascular disease information presented on the Internet and the role in patient education with simple search techniques.

METHODS

The arbitrarily chosen search phrases "abdominal aortic aneurysm (AAA)," "carotid surgery (CEA)," "claudication surgery," and "leg gangrene surgery" were entered into five common Internet search engines. No attempt was made to refine searches. As indicated by the search engines, the 50 most commonly encountered web sites for both AAA and CEA were reviewed. The first 25 claudication sites and the first 25 gangrene sites were combined for a total of 50 leg ischemia (LIS) sites. An information score (IS) was developed as a weighted score ranging from 0 (poor) to 100 (outstanding) and was designed to assess how well the web page educated the patient about the disease, the treatment options, and the medical and surgical complications. Each vascular surgery web site was classified according to the author, the referenced information source, and the therapeutic recommendations. This was followed by an evaluation of each web site with the IS independently scored by two observers.

RESULTS

Of the 150 web sites, 146 were accessible. Ninety-six sites (65.8%) had no useful patient-oriented information (IS < 10). The mean IS and the ranges were: AAA, 14.9 (0 to 72.0); CEA, 17.5 (0 to 77.0); and LIS, 12.2 (0 to 44.5; P =.9). The mean IS of the 59 sites with scores of more than 10 were: AAA, 39.8 (n = 17); CEA, 44.8 (n = 19); and LIS, 24.8 (n = 23; P <.01, as compared with LIS scores). Differences in IS between observers were not significant (P =.9). Misleading or unconventional care recommendations were recognized in one AAA site (1 of 47, 2.1%), two CEA sites (2 of 49, 4.1%), and 13 LIS sites (13 of 50, 26.0%). The Joint Vascular Societies web page was identified only as a tertiary link.

CONCLUSION

Patient-oriented vascular surgery information, for common vascular diseases, is difficult to find on the Internet. The overall quality is poor, and information is difficult to obtain in part because of the large number of irrelevant sites. Of the sites that were relevant to patient education (33%), one third presented information that was classified by the authors as misleading or unconventional. This was most apparent in the leg ischemia sites. The Internet is a poor overall source of patient-oriented vascular surgery information and education. Focused and refined searches and improvements in search engines and educational web sites may yield improved information. Public and medical community awareness needs to be improved regarding the severe limitations of the Internet as an information resource.

Raynaud's syndrome in workers who use vibrating pneumatic air knives

PURPOSE

The use of vibrating tools has been shown to cause Raynaud's syndrome (RS) in a variety of workers, including those who use chain saws, chippers, and grinders. The diagnosis of RS in workers who use vibrating tools is difficult to document objectively. We studied a patient cohort with RS caused by the use of a vibrating pneumatic air knife (PAK) for removal of automobile windshields and determined our ability to document RS in these workers by means of digital hypothermic challenge testing (DHCT), a vascular laboratory study that evaluates digital blood pressure response to cooling.

METHODS

Sixteen male autoglass workers (mean age, 36 years) with RS were examined by means of history, physical examination, arm blood pressures, digital photoplethysmography, screening serologic studies for underlying connective tissue disorder, and DHCT.

RESULTS

No patient had RS before they used a PAK. The mean onset of RS (color changes, 100%; pain, 93%; parathesias, 75%) with cold exposure was 3 years (range, 1.5 to 5 years) after initial PAK use (mean estimated PAK use, 2450 hours). Fifty-six percent of workers smoked cigarettes. The findings of the physical examination, arm blood pressures, digital photoplethysmography, and serologic testing were normal in all patients. At 10 degrees C cooling with digital cuff and patient cooling blanket, a significant decrease in digital blood pressure was shown by means of DHCT in 100% of test fingers versus normothermic control fingers (mean decrease, 75%; range, 25% to 100%; normal response, less than 17%; P <.001). The mean follow-up period was 18 months (range, 1 to 47 months). No patient continued to use the PAK, but symptoms of RS were unchanged in 69% and worse in 31%.

CONCLUSION

PAK use is a possible cause of vibration-induced RS. The presence of RS in workers who use the PAK was objectively confirmed by means of DHCT. Cessation of PAK use in the short term did not result in symptomatic improvement.

Improved results with conventional management of infrarenal aortic infection

PURPOSE

Interest in alternative methods, such as autogenous vein grafts and aortic allografts, for the management of infrarenal aortic infection (IRAI) has been stimulated by the historically disappointing results with conventional surgical management. Recently, there have been dramatic improvements in the results of axillofemoral bypass grafting (AXFB) followed by excision of the IRAI that have gone relatively unrecognized. The purpose of this report is the presentation of modern-day results in the treatment of IRAI with conventional surgical methods.

METHODS

From January 1, 1983, through June 30, 1998, patients with IRAI underwent treatment with AXFB and complete excision of the IRAI. The patients were followed for survival, limb salvage, and AXFB graft patency. The results were tabulated with life-table methods.

RESULTS

During the 15-year study period, 60 patients (51 men, nine women; mean age, 68 years) underwent treatment for IRAI (50 graft infections, including 16 graft-enteric fistulae, and 10 primary aortic infections). The mean follow-up period was 41 months. The perioperative mortality rate was 13% (12% for graft infection, and 20% for primary infection). The overall 2-year and 5-year survival rates were 67% and 47%, respectively. The limb salvage rates at 2 and 5 years were 93% and 82%, respectively. The 5-year primary AXFB graft patency rate was 73%.

CONCLUSION

These results show an improvement with the conventional management of IRAI equal or superior to those results reported with alternative methods, including femoral vein grafts or aortic allografts. These results should be regarded as the modern standard with which alternative therapies can be compared.

Non-heart-beating organ donation: process and review

To combat the national shortage of donor organs and meet the needs of more than 60,000 patients awaiting transplant, many organ procurement organizations have reevaluated non-heart-beating organ donation (NHBD) as one solution. Non-heart-beating donation is the process by which organs are recovered from patients after the pronouncement of death by cardiopulmonary criteria. Recent media reports have misled health care providers to believe that this is a new donation procedure; however, NHBD provided the foundation for modern clinical transplantation. This article describes non-heart-beating donor evaluation criteria, the donation process, associated ethical considerations and the role of the advance practice nurse in assisting families with this end-of-life decision. A case study will be presented followed by a summary of transplant recipient patient and graft survival outcomes.

Duplex scanning alone is not sufficient imaging before secondary procedures after lower extremity reversed vein bypass graft

PURPOSE

Duplex surveillance of lower extremity reversed vein bypass grafts (LERVG) is a means of identifying patients at risk for occlusion. The perceived accuracy of duplex scan as a means of identifying stenoses has led many surgeons to perform graft revision on the basis of duplex scan alone. This may result in missing additional lesions that are threatening patency. To assess the role of duplex scan as the sole imaging method before revision of LERVGs, we reviewed consecutive patients undergoing revisions who underwent preoperative arteriography after identification of duplex scan abnormalities.

METHODS

Duplex scan results, operative reports, and preoperative arteriograms for patients undergoing LERVG revision from January 1990 to December 1997 were reviewed. A standard duplex scan surveillance protocol was followed, and attempts were made to survey the entire graft, including inflow and outflow. Duplex scan results were compared with the results of preoperative arteriograms and the operation performed to determine if all significant lesions were identified by means of duplex scan alone.

RESULTS

Two hundred five LERVG revisions were performed. The 5-year assisted primary patency rate was 91%. In 119 cases (58%), arteriography did not contribute significantly to duplex scan findings. Arteriography significantly contributed to operative planning in 86 cases (42%). In 38 cases (19%), only a low-flow state was identified by means of duplex scan, and a correctable stenosis was identified by means of arteriography. In 48 cases (23%), additional significant lesions corrected at operation were identified by means of arteriography. These included 26 inflow, 16 graft, and 8 outflow lesions. Arteriography was most useful as a means of determining the revision procedure performed when there were inflow lesions (P <.05) or when the proximal anastomosis was to the profunda or superficial femoral arteries (P <.05). All frequently performed bypass graft configurations had some discrepancy between arteriographic and duplex scan findings.

CONCLUSION

Available data do not permit prediction of which LERVG are immune from missed lesions in a duplex scan surveillance protocol. This suggests to us that arteriography is mandatory before LERVG revisions.

Inferior epigastric artery pseudoaneurysm: a complication of paracentesis

Two patients had inferior epigastric artery pseudoaneurysms after therapeutic paracentesis for ascites caused by portal hypertension. The first patient, a 62-year-old man, had a two-week history of left lower quadrant pain, tenderness, and nonpulsatile mass after a paracentesis for ascites. A left inferior epigastric artery pseudoaneurysm measuring 10 cm in diameter and 20 cm in length was diagnosed by means of Duplex ultrasound and arteriography. The patient was treated with percutaneous embolization, with successful thrombosis of the pseudoaneurysm. The second patient, a 33-year-old woman, had a six-week history of left lower quadrant pain, tenderness, and nonpulsatile mass after a paracentesis for ascites. Computerized tomography and arteriography showed a left inferior epigastric artery pseudoaneurysm, measuring 7 cm in diameter and 9 cm in length. The patient was treated with percutaneous embolization with successful thrombosis of the pseudoaneurysm. Both patients were discharged in good condition 2 days after embolization. Inferior epigastric artery pseudoaneurysm is a complication of paracentesis, and percutaneous embolization may be preferable to surgical repair in patients with chronic liver failure and portal hypertension.

Prophylactic repair of renal artery stenosis is not justified in patients who require infrarenal aortic reconstruction

PURPOSE

Simultaneous prophylactic repair of asymptomatic renal artery stenosis (ARAS) in patients who require infrarenal aortoiliac reconstruction is controversial. This study documents the natural history of ARAS in patients who require aortic reconstruction.

METHODS

Two hundred patients who required aortic reconstruction from 1985 to 1990 for indications other than hypertension or renal salvage were identified. ARAS was not repaired. Preoperative angiograms were available for 171 of 200 patients and were reviewed for renal artery stenosis. Patients were assessed for atherosclerotic risk factors, survival, preoperative and follow-up blood pressure, serum creatinine level, antihypertensive medication usage, and need for dialysis.

RESULTS

The mean duration of follow-up was 6.3 years. Twenty-four of 171 patients (14%) had preoperative unilateral 70% to 99% diameter reduction ARAS, and eight (5%) had bilateral 70% to 99% ARAS. Clinical features associated with > or =70% ARAS included coronary artery disease, increased age, and a diagnosis of hypertension (p < 0.05). Patients with > or =70% ARAS did not have a decreased 7-year survival rate (66% vs 84%; p = 0.10) but had higher systolic blood pressures (153 +/- 25 vs 138 +/- 30 mm Hg; p < 0.05) as well as increased numbers of antihypertensive medications at follow-up (1.1 +/- 0.2 vs 0.7 +/- 1; p < 0.05). The mean serum creatinine level (1.1 +/- 0.3 preoperative vs 1.4 +/- 0.8 mg/dl; p = NS) was not increased. One patient (0.58%) with polycystic kidney disease and minimal renal artery stenosis required dialysis.

CONCLUSIONS

High-grade ARAS in patients who are undergoing infrarenal aortic reconstruction is associated at late follow-up with increased systolic blood pressure and a need for increased numbers of antihypertensive medications, but not decreased survival rate, dialysis dependence, or an increase in serum creatinine level. These data do not support renal artery repair in patients with ARAS who undergo infrarenal aortic reconstruction.

Upper extremity arterial disease: etiologic considerations and differential diagnosis

Upper extremity ischemia is an unusual clinical entity. Using a careful history and physical examination, detailed vascular laboratory testing, serological tests, and occasionally arteriography, it is possible to determine the cause in most patients. Most patients presenting with upper extremity ischemia have small vessel disease that is not amenable to surgical treatment. The primary treatment of upper extremity ischemia remains cold avoidance, with pharmacological treatment added in a limited number of patients. A patient's long-term prognosis can be determined based on initial serological studies and the presence or absence of arterial obstruction. Patients with no serological or arterial abnormalities usually continue to have upper extremity ischemic symptoms, but these remain only a nuisance. Patients with either serological abnormalities or arterial obstruction have a mild to moderate risk of progressive symptoms. Those patients with combined serological abnormalities and arterial obstruction at presentation are most likely to have continued difficulties. A significant number of these patients, approximately 50%, are most symptomatic at the time of initial presentation and improve under follow-up.

Surgical treatment of infected aortic aneurysm

BACKGROUND

We report results of infected aortic aneurysms treated by a single group over 20 years.

METHODS

Retrospective review.

RESULTS

Seventeen patients were treated, 10 with infrarenal and 7 suprarenal infections. All had abdominal/back pain, 88% were febrile, 71% had leukocytosis, and 24% were hemodynamically unstable. The most common responsible organism was Staphylococcus aureus (29%) followed by Salmonella organisms (24%). All suprarenal infections were gram-positive organisms. Infrarenal infections were treated with preliminary axillofemoral bypass followed by aortic resection. Suprarenal infections were treated with either in situ prosthetic graft or patch repairs. Operative survival was 90% for infrarenal and 57% for suprarenal infections. Operative deaths occurred in the setting of overwhelming sepsis and/or severe preoperative hemodynamic instability. There was no limb loss, renal failure, or intestinal ischemia. Late deaths occurred in 4 patients at 1.3 to 6.3 years postoperatively and were unrelated to their aortic repairs. Nine patients remain alive with a median follow-up of 2 years. There have been no late aortic or graft infections.

CONCLUSIONS

In the absence of hemodynamic instability and uncontrolled sepsis, infected aortic aneurysms can be successfully repaired with durable results.

Predictors of outcome of forefoot surgery for ulceration and gangrene

BACKGROUND

Surprisingly little is known about the long-term outcome of forefoot surgery for limb salvage.

METHODS

From January 1, 1992 through December 31, 1996, patients requiring toe amputation or forefoot surgery were prospectively entered into a computerized database and followed up for healing, need for repeat foot surgery, or major amputation (below or above knee).

RESULTS

A total of 162 patients (mean age 65 years), 72% diabetic, 10% with end-stage renal disease (ESRD), and 73% without palpable pulses, were entered into the study. Mean follow-up was 25 months. Of patients without palpable pulses (n = 98), 83% underwent concomitant or subsequent limb revascularization. Eleven of 98 revascularization procedures (11%) were hemodynamically unsuccessful. Nonhealing of the initial forefoot procedure occurred in 14%, and late repeat foot surgery (following initial healing) was required in an additional 14%. Major amputation was eventually required in 30 (18.5%) patients. Multivariate analysis indicated that unsuccessful revascularization, but not diabetes or ESRD, predicted nonhealing and major amputation (P <0.0001). Patients presenting with palpable pulses and neuropathic ulcers were at risk for late, repeat foot surgery, but not major amputation (P = 0.0015).

CONCLUSIONS

In patients requiring toe or partial forefoot amputation, success of revascularization is the primary predictor of initial healing and freedom from major amputation. Neuropathic ulceration predicts need for repeat foot surgery following healing.

Pulmonary embolism is associated with the combination of isolated calf vein thrombosis and respiratory symptoms

PURPOSE

Overall prevalence of pulmonary embolism (PE) in patients with deep venous thrombosis (DVT) isolated to calf veins is low. However, the prevalence of PE in the subgroup of patients with respiratory symptoms and isolated calf vein thrombosis (CVT) is unknown. Such information is important in determining whether patients with CVT only and respiratory symptoms should undergo evaluation for PE. The purpose of this study was to determine the prevalence of PE in patients with respiratory symptoms and isolated CVT.

METHODS

From 1992 through 1994, all patients assessed by duplex scanning for lower extremity DVT were reviewed, and those found to have isolated CVT and lower extremity or respiratory symptoms were identified. Patients who had respiratory symptoms or later developed respiratory symptoms in addition to lower extremity symptoms underwent pulmonary angiography or ventilation/perfusion (V/Q) scanning. Positive results on pulmonary arteriograms or "high probability" V/Q scans were considered diagnostic of PE.

RESULTS

There were 105 patients with isolated CVT and symptoms. Twenty-six patients had respiratory symptoms; nine (35%) had PE and two died. Seventy-nine patients had only lower extremity complaints; five later developed respiratory symptoms. All five had PE and none had progression of CVT on repeat duplex scanning. Neither age, gender, prior DVT/PE, obesity, pregnancy, medication, known malignancy, smoking, recent surgery, or trauma predicted PE.

CONCLUSIONS

Patients with respiratory symptoms and duplex diagnosed isolated CVT have a high prevalence of PE and require pulmonary angiographic or V/Q scanning to rule out PE.

Prospective comparison of infrainguinal bypass grafting in patients with and without antiphospholipid antibodies

PURPOSE

The antiphospholipid antibodies (APL)-anticardiolipin antibodies (ACL) and lupus anticoagulant (LA)-are widely believed to be associated with decreased lower extremity bypass graft patency rates. To date, no prospective cohort study has confirmed this assumption. A prospective comparison of the result of infrainguinal revascularization procedures performed since 1990 in patients with and without APL forms the basis of this report.

METHODS

Patients who underwent elective infrainguinal bypass procedures from 1990 to 1994 were evaluated for hypercoagulable states (ACL, LA, protein C, protein S, and antithrombin III). Patient data were prospectively entered in a computerized vascular registry, and postoperative follow-up was maintained for life. Graft patency, limb salvage, and patient survival rates were calculated by life-table methods.

RESULTS

Three hundred twenty-seven lower extremity bypass grafting procedures were performed in 262 patients. APLs were present in 83 patients (32%); 70 patients (84%) had ACLs only, 11 patients (13%) had LA only, and two patients (3%) had both ACLs and LA. There was no significant difference between APL-positive and APL-negative patients with respect to demographics, associated medical conditions, indication for operations, and type of procedures performed. More patients who had APLs had warfarin treatment after surgery (43% vs 24%, p = 0.002). Life table 4-year primary patency rates showed minimal difference (APL-positive, 43%; APL-negative, 59%; p = 0.087), and no significant difference was noted in assisted primary patency rates (APL positive, 72%; APL negative, 73%; p = NS), limb salvage rates (APL positive, 79%; APL negative, 88%; p = NS), and patient survival rates (APL positive, 67%; APL negative, 66%; p = NS).

CONCLUSIONS

APLs were found in a surprising one third of the patients who underwent leg bypass grafting procedures. The majority of APLs identified were ACLs (87%). There was minimal difference in graft primary patency rates, and no difference in assisted primary patency, limb salvage, and survival rates between patients with and without APLs who underwent leg bypass grafting procedures. The extreme morbidity rate associated with APLs in previous reports is not confirmed by this prospective study. APLs should not be regarded as a contraindication to indicated leg bypass grafting procedures.

Improving selection of patients with less than 60% asymptomatic internal carotid artery stenosis for follow-up carotid artery duplex scanning

PURPOSE

The Asymptomatic Carotid Atherosclerosis Study (ACAS) indicated significant benefit from endarterectomy compared with medical therapy for patients with 60% to 99% asymptomatic internal carotid artery (ICA) stenoses. To date, optimal selection of patients for vascular laboratory follow-up to determine progression from < 60% to > or = 60% asymptomatic ICA stenosis is unknown. To determine which patients with < 60% asymptomatic ICA stenoses are at greatest risk for short-term progression to > or = 60% without symptoms, we reviewed vascular laboratory results and clinical risk factors of consecutive patients who were prospectively observed in a study of atherosclerosis progression.

METHODS

Carotid duplex studies were obtained every 6 months and were reviewed for progression from < 60% to > or = 60% asymptomatic ICA stenosis by using criteria that were developed and reported by our laboratory. Clinical risk factors and velocities from initial duplex scans were analyzed for association with progression from < 60% to > or = 60% ICA stenoses without symptoms.

RESULTS

Two hundred sixty-three patients (mean age, 66 years) with 434 asymptomatic < 60% ICA stenoses were prospectively observed for a mean of 20 months, with a mean of four examinations per patient. Seventeen patients (6.5%) and 18 ICAs (4%) progressed without symptoms to > or = 60% ICA stenoses at a mean of 18 months. Clinical risk factors associated with progression to > or = 60% asymptomatic ICA stenosis included elevated systolic blood pressure and decreased ankle-brachial index (p = 0.05). The mean initial ICA peak systolic velocity (PSV) in ICAs that progressed to > or = 60% asymptomatic stenoses was 180 cm/sec, compared with 104 cm/sec in asymptomatic ICAs that did not progress to > or = 60% (p = 0.0003). Thirty-one percent of asymptomatic ICAs that had initial PSVs of 175 cm/sec or greater progressed to > or = 60% stenosis, whereas only 1.8% that had initial PSVs less than 175 cm/sec progressed to > or = 60% asymptomatic stenoses (p < 0.001). The life-table-determined rate of freedom from progression to > or = 60% stenosis was 94% at 4 years for asymptomatic ICA lesions that had initial PSVs less than 175 cm/sec, compared with 14% at 3 years for lesions that had initial PSVs > or = 175 cm/sec.

CONCLUSIONS

Early progression from < 60% asymptomatic ICA stenoses to > or = 60% asymptomatic ICA stenoses occurs infrequently. Patients who are at the greatest risk of early progression without symptoms to an ACAS-positive lesion can be identified from the ICA PSV at their initial duplex examination. Early vascular laboratory follow-up of asymptomatic ICA stenoses may be limited to a relatively small group.

Nursing care of a patient with chronic abdominal pain secondary to porphyria: a case study

Patients with porphyria present a wide variety of challenges to healthcare providers. The nursing care required by patients with porphyria is similar to that needed by patients suffering from chronic illnesses. This nursing care includes pain management, management of nutrition, an appropriate bowel regimen, the recognition of possible complex neurological manifestations, and psychosocial support (Shively et al., 1994). A thorough understanding of the disease process is essential to accurately assess the patient and develop an effective plan of care.

"Just in time" decision making for ICU care after carotid endarterectomy

BACKGROUND

Many patients undergoing carotid endarterectomy (CE) do not require active intensive care unit (ICU) care (AIC). Until recently, all patients spent 24 hours postoperatively in an ICU, but many of these patients were simply monitored and did not need unique ICU services.

METHODS

To aid in developing a selective policy for ICU admission following CE, we reviewed preoperative risk factors, recovery room course, and total hospital stay of 126 patients for 2 years when postoperative ICU admission was routine. Preoperative assessment included presence or absence of cardiac disease, hypertension, severe respiratory disease, diabetes, arrhythmia, renal failure, and a Goldman cardiac risk score. The operative, recovery room, and ward records were reviewed for conditions requiring AIC. Requirement for AIC was defined as need for infusion of vasoactive, bronchodilator, or antiarrhythmic medication beyond the recovery room period. In addition, treatment for coronary ischemia or MI, need for active diuresis, perioperative neurological event, or requirement for mechanical ventilation were indications for AIC.

RESULTS

There were 132 CEs in 126 patients; 37% required AIC as defined above. When patients who required AIC were compared with patients not requiring AIC, the only significant difference was the number of risk factors per patient. Goldman cardiac risk class I patients were at less risk for cardiac morbidity than the combined Class II and III patients.

CONCLUSIONS

In an individual patient, preoperative risk assessment does not aid in predicting the need for AIC following CE. Selection of patients for ICU admission following CE can be accurately determined by a short period of recovery room observation.

Comparison of axillofemoral and aortofemoral bypass for aortoiliac occlusive disease

PURPOSE

A comparison of aortofemoral bypass grafting (AOFBG) and axillofemoral bypass grafting (AXFBG) for occlusive disease performed by the same surgeons during a defined interval forms the basis for this report.

METHODS

Data regarding all patients who underwent AOFBG of AXFBG for lower-extremity ischemia caused by aortoiliac occlusive disease were prospectively entered into a computerized vascular registry. The decision to perform AOFBG rather than AXFBG was based on assessment of surgical risk and the surgeon's preference. This report describes results for surgical morbidity, mortality, patency, limb salvage, and patient survival for procedures performed from January 1988 through December 1993.

RESULTS

We performed 108 AXFBGs and 139 AOFBGs. AXFBG patients were older (mean age, 68 years compared with 58 years for AOFBG, p<0.001), more often had heart disease (84% compared with 38%, p<0.001), more often underwent surgery for limb-salvage indications (80% compared with 42%, p<0.001). No significant differences were found in operative mortality (AXFBG, 3.4%; AOFBG, <1.0%, p=NS), but major postoperative complications occurred more frequently after AOFBG (AXFBG, 9.2%; AOFBG, 19.4%; p<0.05). Follow-up ranged from 1 to 83 months (mean, 27 months). Five-year life-table primary patency, limb salvage, and survival rates were 74%, 89%, and 45% for AXFBG and 80%, 79%, and 72% for AOFBG, respectively. Although the patient survival rate was statistically lower with AXFBG, primary patency and limb salvage rates did not differ when compared with AOFBG.

CONCLUSION

When reserved for high-risk patients with limited life expectancy, the patency and limb salvage results of AXFBG are equivalent to those of AOFBG.

Results of bypass to the popliteal and tibial arteries with alternative sources of autogenous vein

PURPOSE

The goal of an all-autogenous policy for infrainguinal arterial bypass requires that many bypasses be performed with alternative autogenous veins (AAV) because an adequate length of ipsilateral or contralateral greater saphenous vein (GSV) is not available. The durability and efficacy of infrainguinal vein bypasses constructed of venous conduits other than a single segment of greater saphenous vein (SSGSV) is, however, questioned.

METHODS

AAV and GSV bypasses were reviewed from 1980 through 1994. Patients who required bypass to the popliteal or a tibial artery were compared for vascular surgical history and vascular disease risk factors and life-table survival. AAV and SSGSV procedures were compared for indications for surgery, morbidity and mortality rates, limb salvage rates in patients who underwent surgery for limb-salvage indications, subsequent need for revision, and life-table-assisted primary patency.

RESULTS

Nine hundred nineteen autogenous vein bypasses were performed to the popliteal or a tibial artery--187 (20%) with AAVs, including whole or partial arm vein conduits in 144 grafts (77%). One hundred fourteen AAVs (61%) required vein splicing. The mortality rate was 2% for SSGSV bypasses and 1% for AAV bypasses. The morbidity rate was higher for GSV surgery as a result of increased wound complications (11% vs 5%; p=0.02). Sixty-seven percent of patients with AAV bypass extremities had undergone previous ipsilateral arterial surgery, compared with 20% of patients with SSGSV bypasses (p0.0005). AAV bypasses were more likely to be to a tibial artery (71% vs 45%; p<0.0001). Twelve percent of SSGSV and 15% of AAV popliteal bypasses required revision (p=NS). The 5-year assisted primary patencies were 82%, 77%, and 63%, with limb salvage rates of 91%, 86%, and 74% for ipsilateral SSGSV, contralateral SSGSV, and AAV femoropopliteal bypasses, respectively. Twelve percent of SSGSV and 30% of AAV tibial bypasses required revision (p=0.0001). The 5-year assisted primary patencies were 74%, 82%, and 72%, with limb salvage rates of 84%, 92% and 78% for ipsilateral SSGSV, contralateral SSGSV, and AAV femorotibial bypasses, respectively.

CONCLUSION

AAV bypasses can provide overall results comparable with SSGSV bypasses.

Upper extremity thromboembolism after axillary-axillary bypass grafting

Two patients experienced upper extremity thromboembolism after axillary-axillary bypass grafting (AxAG) for symptomatic subclavian artery stenosis. The first patient, a 67-year-old male, presented with left upper extremity thromboembolism 3 years after AxAG with 8 mm externally support PTFE. An arteriogram revealed a patent AxAG, thrombus in the proximal left subclavian arterial stump just distal to its occlusion, and multiple digital artery emboli. The patient was treated with warfarin for 8 months, with resolution of symptoms. The second patient, a 57-year-old male, occluded his AxAG (8 mm knitted Dacron) with minimal return of symptoms. Non-operative treatment was elected and 4 years later the patient presented with right upper extremity (donor side) thromboembolism. Arteriography revealed occlusion of the AxAG, radial artery, and digital arteries of the index, long and ring fingers. Thrombolytic therapy of the right arm was undertaken with minimal improvement. Subsequent detachment of the AxAG and placement of an interposition reversed saphenous vein graft was performed. Both patients continue to be asymptomatic during follow-up of 4.7 and 2.0 years, respectively.

Long-term outcome of Raynaud's syndrome in a prospectively analyzed patient cohort

PURPOSE

Knowledge of the long-term clinical outcome of Raynaud's syndrome (RS), essential both for patient counselling and formulation of optimal therapeutic recommendations, is conspicuously deficient in current medical literature. We have prospectively monitored 1039 patients with RS, 118 (11.4%) for more than 10 years to determine whether initial characterization was able to predict outcome.

METHODS

At initial presentation, patients were divided into four groups on the basis of vascular laboratory and serologic testing results: vasospastic, serologically positive (spast,sero+) and negative (spast,sero-) and obstructive, serologically positive (obst,sero+) and negative (obst,sero-).

RESULTS

Connective tissue disease (CTD) was present initially in 48.6% of patients with spast,sero+ results and 72.9% of patients with obst,sero+ results. Of the remaining patients in these groups, progression to CTD during follow-up occurred in 16.4% of patients with spast,sero+ results and 30.4% of patients with obst,sero+ results. In the > 10-year follow-up group, progression to CTD occurred in 81.8% of patients in the obst,sero+ group. Progression to CTD occurred in 2.0% of patients in the spast,sero-group and 8.5% of patients in the obst,sero- group. Digital ulcers occurred in 15.5% of patients in the spast,sero+ group, 5.2% of patients in the spast,sero- group, 55.6% of patients in the obst,sero+ group, and 48.2% of patients in the obst,sero- group. Digital or phalangeal amputations were required in 1.4%, 1.6%, 11.6%, and 19.0% of these patients, respectively.

CONCLUSIONS

The long-term outcome of patients with RS can be predicted by initial serologic studies and separation into vasospastic and obstructive categories. Initial serologic positivity strongly predicts the development of CTD. Initial vascular laboratory classification of obstructive RS strongly predicts digital ulcerations, which occurred in half of these patients regardless of initial serologic study results. Amputations were required in 10% to 20% of patients with obstructive RS. These occurrences did not increase with increased duration of disease. Ulcerations and amputations were rare in patients initially with vasospastic RS.

Deep vein thrombosis associated with lower extremity amputation

PURPOSE

Patients undergoing lower extremity amputation are perceived to be at high risk for deep vein thrombosis (DVT). Limited data are available, however, to confirm this impression. The purpose of this study is to prospectively document the incidence of DVT complicating lower extremity amputation.

METHODS

During a recent 28-month period, 72 patients (71 men, 1 woman; mean age 68 years) undergoing major lower extremity amputation (31 above-knee and 41 below-knee) were prospectively evaluated with perioperative duplex scanning for DVT.

RESULTS

DVT was documented in nine (12.5%) patients (one bilateral, four ipsilateral, and four contralateral to amputation). Patients with a history of venous disease were at significantly higher risk for development of DVT (p = 0.02). Thrombi were located at or proximal to the popliteal vein in eight patients and were isolated to the tibial veins in one patient. DVT was identified before operation in six patients and after operation in three. Patients with DVT were treated with heparin anticoagulation, with no patient experiencing clinical symptoms compatible with pulmonary embolism.

CONCLUSIONS

In our recent experience, lower extremity amputation is associated with DVT at or proximal to the popliteal vein in 11% of patients. Documentation of DVT prevalence is essential to assist surgeons in planning a management strategy for prevention, diagnosis, and treatment of DVT associated with lower extremity amputation.

Do normal early color-flow duplex surveillance examination results of infrainguinal vein grafts preclude the need for late graft revision?

PURPOSE

Optimal duration of postoperative duplex surveillance of infrainguinal vein grafts is not known. Previous reports have suggested nearly all vein graft stenoses are present within the first postoperative year, and normal duplex examination results during this time eliminate the need for ongoing graft surveillance. To determine whether surveillance may be safely discontinued in patients with normal early postoperative surveillance studies, we reviewed the color-flow surveillance examinations in our patients who underwent infrainguinal reverse vein graft revisions during a 4 1/2 year period.

METHODS

Clinical and vascular laboratory records were reviewed of all patients who underwent infrainguinal reverse vein bypass grafting followed by subsequent graft revision for a duplex scanning-detected abnormality at our institution between January 1990 and July 1994.

RESULTS

Of 447 infrainguinal reverse vein bypasses performed, 36 (8.1%) underwent surgical revision as a result of an abnormal finding during routine duplex surveillance. The initial postoperative duplex examination was obtained within 2 weeks of graft implantation in 23 (64%) patients, between 2 weeks and 3 months in 10 (28%) patients, and between 3 and 6 months in three (8%) patients. Duplex abnormalities prompting revision included 11 (31%) grafts with a mid-graft peak systolic velocity (PSV) < or = 45 cm/sec, 23 (64%) grafts with a focal PSV > or = 200 cm/sec, one graft with a PSV > or = 150 cm/sec but < 200 cm/sec, and one thought to be occluded by duplex but found to be patent by angiography. Abnormal duplex findings were initially detected within 2 weeks of graft implantation in five (14%) patients, between 2 weeks and 3 months in eight (22%) patients, from 3 to 6 months in 12 (33%) patients, from 6 to 12 months in six (17%) patients, and > 1 year in five (14%) patients. In only 25% of cases were mid-graft PSVs < or = 45 cm/sec or focal velocities > or = 200 cm/sec identified on the initial examination; 75% were found during subsequent surveillance.

CONCLUSIONS

Although most reverse vein graft abnormalities detected by duplex surveillance and prompting graft revision appear within the first postoperative year, many are not detected on the initial examination. In our recent experience 31% of duplex abnormalities leading to vein graft revision were first detected more than 6 months after operation. Discontinuation of graft surveillance based on normal early findings will result in thrombosis of some vein grafts that may otherwise be salvaged.

Diagnosis and long-term clinical outcome in patients diagnosed with hand ischemia

PURPOSE

The long-term clinical outcome of patients diagnosed with digital artery obstruction and symptomatic hand ischemia is largely unknown. Our long-term experience with the diagnosis of symptomatic digital artery obstruction and the long-term natural history of this condition forms the basis for this report.

METHODS

From 1971 to 1985, 44 patients with symptomatic hand ischemia and palmar or digital arterial obstruction underwent arteriography and digital photoplethysmography (PPG). Patients were grouped according to severity of hand ischemia symptoms, including ulceration and digital amputation and the presence of a connective tissue disease (CTD). Arteriography was compared with PPG by creating an objective severity scale (digital obstruction index [DOI]).

RESULTS

Average follow-up was 15.2 years (range 10 to 22 years). Initially 21 patients (48%) had moderate symptoms, and 23 patients (52%) had severe symptoms of hand ischemia. Follow-up symptoms in 28 patients improved (13 of 26 with CTD, 15 of 18 without CTD), in 15 patients (12 of 26 with CTD, 3 of 18 without CTD) remained unchanged, and in only 1 patient (1 of 26 with CTD) worsened. Seventeen (65%) patients with CTD (n = 26) had development of one or more ulcers, and six (24%) underwent one or more digital amputations. Four (22%) patients without CTD (n = 18) had finger ulceration (p < 0.012 compared with patients with CTD), and one patient (6%) underwent subsequent digital amputation (p = NS). The arteriography-DOI and PPG-DOI were equally accurate in determining severity of finger ischemia as manifested by severity of symptoms or ulcer development.

CONCLUSIONS

The favorable long-term prognosis of symptomatic finger artery occlusion described herein mandates the avoidance of premature finger amputation. Patients with CTD fare worse, but even in this group tissue loss is modest. Finger PPG is as accurate as arteriography for determining severity of hand ischemia.