The incidence and management of complications of venous access in home parenteral nutrition (HPN): A 19 year longitudinal cohort series.

BACKGROUNDS AND AIMS: Long term central venous access for Home Parenteral Nutrition (HPN) is associated with catheter related complications. The most studied and well known of these is Catheter Related Blood Stream Infection (CRBSI). This paper looks at other venous access complications, including blocked and damaged catheters, catheter related thrombosis and CRBSI. This paper will also present treatment outcomes for each of these complications. This paper will also examine if there are any correlating patient or catheter related factors that can help predict future catheter related complications. By demonstrating the treatment outcomes for each line complication, it is hoped this will contribute to the literature that could be used for standard setting in complications related to long term central venous access. METHODS: HPN data were analysed from the Greater Glasgow and Clyde (GGC) Home Parenteral Nutrition Database (HPN) which is a comprehensive, prospectively maintained electronic record of all HPN patients treated in GGC. The time period of data collection was 1998-2017. Descriptive statistics were used to report data frequency, age, and catheter days' distributions. Data were not normally distributed and so non-parametric tests were used. Spearman's Rho correlation was used to measure correlation between two numeric groups. Catheter complications were reported as a rate in count data, meaning that more than one event could be recorded per patient, with 1000 catheter days as the person-time denominator. Poisson means test and Fisher exact tests were used to compare different rates, as complications were treated as count data increasing over variable total time periods. P < 0.05 with 95% confidence interval (CI) was considered significant in all tests. Comparisons between binary data sets used two sample t-tests to compare the groups. RESULTS: From 169 patients, 101 (59.8%) were female and 68 (40.2%) were male. The age when first starting HPN ranged from 16 to 79 years old with a median of 56 years. Total catheter days was 173,151 derived from 408 catheter insertions on 169 patients. 282 complications occurred in 85 patients over the study period. An overall catheter complication rate of 1.62/1000 days was found. 84 patients did not experience a single complication. There were 171 proven catheter infections in 66 patients over the study period. Infection rate from the entire period of report was 1.35 infections/1000 catheter days. This decreased over time. Infection was found to be correlated with length of time on HPN, catheter location, catheter diameter and use of Taurolock-Hep100. Thrombosis (n = 16) was associated with total time on HPN (r2 = 0.187, P < 0.05) and the number of infections (r2 = 0.207, P < 0.05). Damage was strongly associated with increasing time on HPN with (r2 of 0.494 and P < 0.005). Blockage was not associated with any patient or catheter factors. Overall catheter salvage rate for CRBSI by antibiotic treatment was 61.87%. Success varied according to organism cultured. Catheter salvage was less successful in other complications and overall catheter salvage rate was 41,115 catheters were salvaged from 282 complications. CONCLUSIONS: This study has provided a baseline for rates of less common venous access complications in HPN and their management. Catheter salvage is possible after at least 41% of complications. It is likely that experience is helpful whether that of individual patient, the team or a clinical network. Our results support the use of smaller central venous catheters, in upper body veins, and the use of Taurolock-Hep100 in patients who have recurrent infections.

Outcome after ligation of infected false femoral aneurysms in intravenous drug abusers.

OBJECTIVES: to determine the outcome of a policy of ligation with observation of infected false femoral aneurysms (IFFA) in intravenous drug abusers (IVDA), particularly with respect to the issue of limb preservation. DESIGN: a retrospective study. MATERIALS AND METHODS: thirty-seven consecutive cases of IFFA in 34 patients accrued over nine years were studied by case note review and by clinical or telephone interview. RESULTS: in 34 cases of ligation of primary IFFA there were no amputations, with patients describing claudication only in follow-up. In three cases of second IFFA in the same limb, repeat ligation resulted in two viable limbs with claudication only, and one above-knee amputation. At the nine year follow-up, all patients were still drug-dependent and considered unsuitable for late revascularisation. There were three deaths and all were drug-related. CONCLUSIONS: in our experience, ligation of IFFA is effective, safe and simple, and is the most appropriate method of dealing with these challenging cases.

The diagnosis and treatment of gastroesophageal reflux disease in a managed care environment, Suggested disease management guidelines.

A group of experts from gastroenterology, internal medicine, health economics, medical outcomes, and managed care met in San Francisco, Calif, on September 27, 1994, in an effort to develop clinically and economically effective disease management guidelines to assist physicians in their treatment of gastroesophageal reflux disease in a managed care environment. This article represents a consensus opinion based on the evidence and expert interpretation at the time of that meeting.

Insonation and impedance analysis in graft surveillance.

Seventy consecutive patients with infrainguinal bypass grafts entered a 1-year graft surveillance programme involving colour duplex scanning, direct graft insonation and computer-assisted impedance analysis. Graft patients with a positive duplex scan, high frequencies on graft insonation or an impedance value above 0.50 subsequently underwent arteriography. Sixteen patients were excluded before the initial surveillance visit. The 54 remaining patients with grafts (30 vein, 24 synthetic) underwent a total of 137 surveillance visits, with 21 grafts confirmed to be 'at risk'. The sensitivity of an impedance value above 0.55 in identifying these grafts was 86 per cent, rising to 95 per cent when combined with graft insonation. Duplex scanning did not identify any abnormalities in 11 grafts that were either shown by arteriography to be 'at risk' or occluded before arteriography. Impedance measurement and graft insonation are simple screening techniques with a high sensitivity (when combined), which identify 'at risk' infrainguinal grafts. Positive graft insonation or an impedance value over 0.55 will identify all 'at risk' vein grafts while minimizing the number of unnecessary arteriograms.

Management of thrombosis in peripheral arterial disease.

There is accumulating evidence that thrombosis contributes to peripheral arterial disease, and that antithrombotic therapy should be considered at all symptomatic stages. In claudication, antiplatelet therapy is indicated in addition to lifestyle advice and sometimes surgery or angioplasty; the place of thrombolysis is unproven. In chronic critical limb ischaemia, prophylaxis of venous thromboembolism by low-dose heparin is indicated during hospitalisation, as is long-term antiplatelet therapy; local thrombolysis or systemic prostanoid infusions are increasingly used. In acute critical limb ischaemia, full dose heparinisation is followed by thromboembolectomy, local thrombolysis, angioplasty and surgery as appropriate. Antiplatelet therapy and/or anticoagulation are employed following such procedures, according to risk factors in the individual patient. Collaboration between vascular surgeons, radiologists and physicians is important in comprehensive patient care.

Hepatic arterial haemodynamics changes following intra-arterial angiotensin II infusion: duplex/colour Doppler sonography.

Previous studies have shown that the delivery of cytotoxic microspheres to liver tumours may be improved by manipulating the tumour to normal liver blood flow ratio using angiotensin II (AT-II). The optimization of this targeting requires the assessment of the temporal blood flow changes induced by agents such as AT-II. Duplex/colour Doppler sonography (DCDS) was evaluated as a means of studying the effects of AT-II infusion on hepatic arterial blood flow (HABF) and arterial resistance in patients with colorectal liver metastases. HABF was measured continuously in six patients with colorectal liver metastases using DCDS before, during and after an infusion of AT-II (15 micrograms in 3 ml of saline over 90 s) via a hepatic artery catheter. The baseline level of HABF was 320 +/- 87 ml/min (mean +/- S.D.), and this was reduced by 70-76% within 30 s of the start of AT-II infusion. HABF recovered rapidly from the end of the infusion, and increased by up to 20% above the baseline for approximately 2 min. Arterial resistance showed reciprocal changes in all cases. These changes were both quantitatively and qualitatively similar to intra-operative measurements previously performed in the same patients using a standard intra-operative flowmeter. The degree of concordance obtained from the intra- and post-operative measurements confirms the effectiveness of DCDS in assessing the temporal changes in hepatic arterial blood flow caused by AT-II. Prior to the start of therapy, the evaluation of vasoconstrictor agents should be carried out in individual patients to predict response, in order to establish the optimal phase for the injection of cytotoxic microspheres.

Saphenous vein grafts for anatomical variations encountered at surgical insertion of a hepatic artery catheter.

Fifty-five consecutive patients, with colorectal metastases confined to the liver, underwent surgical placement of a hepatic artery catheter. At angiography, abnormal hepatic arterial anatomy was present in 33% of patients. In the majority of patients, the hepatic artery catheter was inserted in the conventional manner. In eleven patients with unusual arterial anatomy, a saphenous vein graft was used to create a conduit for the catheter. Satisfactory perfusion was obtained in all patients.

Streptococcus milleri and complex groin abscesses in intravenous drug abusers.

Intravenous drug abuse is an increasing problem. Septic complications occur frequently at the injection site, especially in the groin where large abscesses around the femoral vessels can threaten life or limb. We report four patients with extensive or complex groin abscesses following attempted self-injection into the femoral vein. Streptococcus milleri was cultured from all of these abscesses and prompted a review of the isolation of this organism in this hospital.

Acute aortocaval fistula in association with ruptured aortic aneurysm.

Eight cases of aortocaval fistula are described. In all of them operation was performed with repair of the fistula and replacement of the aneurysm by a prosthetic graft. In seven cases the cause was rupture of an atherosclerotic aneurysm but one case followed rupture of a re-entrant dissecting aortic aneurysm. A fistula is most easily recognized by the sensation of a palpable thrill over the aorta during operation together with systemic venous congestion and a high central venous pressure before aortic clamps are applied. Diagnosis of the fistula before surgery or its recognition during operation and before opening the aorta usually leads to a successful outcome.

An anomalous right iliac artery presenting as iliac stenosis.

An anatomical anomaly of pre-aortic inferior vena cava and retro-psoas iliac artery in a 33-year-old female is reported. This patient presented with severe right leg claudication and was successfully managed by implantation of an aortofemoral graft.

A useful maneuver for hepatic arterial catheterization in patients with metastatic hepatic disease and abnormal vascular anatomy.

The placement of catheters for hepatic arterial perfusion in patients with metastatic hepatic disease and unusual vascular anatomy can be problematic. Many options have been previously described, none of them entirely satisfactory or without risk. We have described herein the use of a saphenous vein graft that is anastomosed to the aberrant hepatic artery as a versatile catheter conduit, which is quick, easy and safe to construct.

Operation for late complications of aortic grafts.

In a period of seven years, 120 revision operations were performed for complications occurring in 1,284 aortic bifurcation grafts. The reasons cited for operation were: graft limb occlusion or stenosis in 82 patients, false aneurysm in 28 and symptomatic disease distal to the graft in ten. Preferred operations were replacement of the graft and distal anastomosis for occlusion or complete reconstruction of the anastomosis with fresh graft material for a false aneurysm. The operative mortality rate was 1.6 per cent and three patients (2.5 per cent) underwent amputation after multiple procedures. This group of 120 patients with complications was compared with a random sample of 300 patients with aortic bifurcation grafts with no complications. In the group with complications, there were significantly fewer patients who underwent sympathectomy or profundaplasty and significantly more with an iliac rather than a femoral artery graft insertion. Those patients who had graft complications develop also had a significantly higher hematocrit level at the first procedure.

Failure of Doppler ankle pressure to predict healing of conservative forefoot amputations.

Fifty minor foot and transmetatarsal amputations were studied to assess the reliability of Doppler ankle blood pressure (DABP) and skin blood flow (SBF) to predict healing. The level of amputation was determined solely on clinical criteria. Thirty-six (72 per cent) of the amputations healed. There was no statistical difference between mean DABP in healed 89 +/- 8 mmHg mean +/- s.e.m.) and non-healed (91 +/- 12 mmHg mean +/- s.e.m.) amputations. SBF was assessed by 125I-iodoantipyrine clearance in 28 patients. There was no correlation between DABP and SBF (r = 0.038). SBF in patients with healed amputations was 14.8 +/- 1.2 (mean +/- s.e.m.) ml 100 g-1 min-1 in contrast to SBF of 5.9 +/- 0.3 (mean +/- s.e.m.) ml 100 g-1 min-1 in the patients with non-healing (P less than 0.01). Where the flow was in excess of 8 ml 100 g-1 min-1 healing was always obtained while a flow of less than 7 ml 100 g-1 min-1 was associated with healing failure. These results suggest that DABP should be interpreted with caution as this technique fails as an accurate means of identifying those patients suitable for forefoot amputations. Skin blood flow assessment appears to provide an absolute value for the prediction of healing potential at this level.