Israel Medical Association Journal

Background: In recent years there has been an increase in endovascular repair of thoracic aortic aneurysms. In cases of insufficient neck length, occlusion of left subclavian artery achieves proper sealing and is usually well tolerated. Selected cases require revascularization of the left subclavian artery, including patients after coronary bypass surgery (left internal mammary to left anterior descending) and those with arm claudication or subclavian steal syndrome.

Objectives: To evaluate the tolerability of left subclavian artery occlusion by stent graft without revascularization.

Methods: Thirty patients with thoracic aortic aneurysms underwent endovascular repair between July 2000 and November 2004. Eleven of them had occlusion of the left subclavian artery that required revascularization in two. Follow-up (average 3 years) included a) blood pressure measurements of both arms at rest, after effort and pulse palpation, and b) vertebral blood flow by duplex scan.

Results: Of nine patients with no revascularization, 8 (89%) tolerated left subclavian artery occlusion with no claudication or steal syndrome; one (11%) suffered mild claudication only after effort and required no intervention. No left radial pulses were palpated in the nine patients. Blood pressure measurements in the left arm showed an average decrease of 40%, which remained constant after induced effort in all patients and was clinically insignificant. Duplex scan demonstrated reverse flow in the left vertebral artery in 8 of 9 patients (89%) and occlusion in 1 (originating in the arch and covered by the stent graft) with no clinical symptoms.

Conclusions: Left subclavian artery occlusion by stent graft is a tolerable procedure in the long term. In most cases, the constant decrease in blood pressure remained unchanged during follow-up and had no significant adverse affects. Most patients do not require revascularization prior to the endovascular procedure.
 

Background: The management of aspirin therapy before an invasive procedure poses a frequent clinical dilemma due to uncertainty regarding b[AS1] leeding versus thromboembolic risks associated with continuation or withdrawal of the drug. There is no evidence-based data to refer to.

Objectives: To assess the opinions of internal medicine physicians regarding aspirin therapy prior to an invasive procedure.

Methods: A questionnaire presenting nine hypothetical cases with different combinations of bleeding and thromboembolic risk was given to physicians in an Internal Medicine Division during a personal interview. For each case the participants had to choose between withdrawal of aspirin prior to an invasive procedure, continuation of aspirin, or substitution of low molecular weight heparin for aspirin. Results: Sixty-one physicians participated in the survey. For a patient with low thromboembolic risk, 77% (95% confidence interval 65.3–86.3%), 95% (87.2–98.7%) and 97% (89.6–99.5%) of physicians elected to discontinue aspirin prior to a low, intermediate or high bleeding risk procedure, respectively. For intermediate risk patients, 23% (95% CI[1] 13.7–34.7%), 59% (46.4–70.8%) and 74% (61.7–83.6%) would discontinue aspirin prior to a low, intermediate or high risk procedure, and 5% (95% CI 1.3–12.8%), 23% (13.7–34.7%) and 18% (9.9–29.2%) would substitute LMWH[2] for aspirin. For a patient with high thromboembolic risk, 1.6% (95% CI 0.08–7.8%), 11.5% (5.2–21.4%) and 18% (9.9–29.2%) recommended discontinuing aspirin prior to a low, intermediate or high risk procedure, respectively. In these situations, 18% (95% CI 9.9–29.2%), 53% (40.0–64.7%) and 57% (44.8–69.3%), respectively, would substitute LMWH for aspirin.

Conclusions: The results of the current investigation may help practicing physicians to decide whether to discontinue aspirin therapy prior to invasive procedures. The possible use of LMWH to replace aspirin as suggested here should be further evaluated in a controlled clinical study.

 

Background: Necrotizing enterocolitis is a common progressive gastrointestinal disease affecting more than 5% of very low birth weight infants and associated with a high mortality rate.

Objectives: To determine whether excessive weight gain in preterm infants is an early sign of NEC[1].

Methods: Seventeen preterm infants with perforated NEC were identified and matched with 17 control subjects for birth weight and gestational age. The postnatal age (days) at diagnosis of NEC was identified, and weight changes as well as clinical and laboratory data were recorded and compared for 7 days prior through 7 days post-diagnosis.

Results: A significant difference in weight gain was noticed between D-1 and D 0. The NEC and control groups gained 5.1% and 1.2%, respectively (P = 0.002). None of the sick infants lost weight on days -1 to D 0.

Conclusions: Excessive weight gain was observed in premature infants who subsequently developed NEC. Daily evaluation of weight changes should be considered part of a strategy for early identification of infants at risk for developing NEC. Future studies are needed to confirm this finding in a prospective manner and to investigate its pathogenesis.

Objectives: To investigate the mechanisms of these effects.

Methods: The study group included 106 long-term care stable geriatric inpatients. Diet and drugs were kept stable. The study lasted 5 weeks; during the first 2 weeks 100 mg aspirin was administered once a day. Clinical and laboratory follow-up were performed at baseline and weekly for the next 3 weeks. The glomerular filtration rate was estimated by creatinine clearance measured in 24 hour urine and serum creatinine, and by the Cockcroft-Gault formula (C-G) equation. Uric acid clearance (Cu acid) was determined from serum concentrations and 24 hour excretion of uric acid. Patients with serum creatinine > 1.5 mg/dl were not included.

Results: After 2 weeks on low dose aspirin, measured creatinine and uric acid clearances decreased significantly compared with the initial values in 70% and 62% of the patients, respectively, with mean decreases of 19% and 17%, respectively (P < 0.001). Blood urea nitrogen increased by 17% while serum creatinine and uric acid concentrations increased by 4% (P < 0.05 for all). The C-G[1] values decreased by 3% (P < 0.05). After withdrawal of aspirin all parameters improved. However, 67% of the patients remained with some impairment in their measured Ccr[2], compared to baseline. Patients who reacted adversely to low dose aspirin had significantly better pre-study renal function (Ccr), lower hemoglobin and lower levels of serum albumin.

Conclusions: Short-term low dose aspirin affected renal tubular creatinine and uric acid transport in the elderly, which may result in a prolonged or permanent deterioration of the renal function. It is suggested that renal functions be monitored even with the use of low dose aspirin in elderly patients.