Impact of activated protein C resistance on general vascular surgical patients

Purpose: The prevalence of activated protein C resistance (APCR) and associated thrombotic morbidity among patients who undergo arterial reconstruction were investigated.Methods: Preoperative assays for functional APCR and factor V (Leiden) mutation were performed on 262 patients who underwent arterial reconstructions that consisted of cerebrovascular surgery (109), aortic or iliofemoral procedures (76), or infrainguinal bypass procedures (77). Patients were monitored for thrombotic complications during the postoperative period.Results: Depending on the stringency of the definition used, functional APCR was detected in 10.6% to 22.0% of patients tested. Factor V (Leiden) was found in 5.3% of patients. Thrombotic morbidity consisting of myocardial infarction, cerebrovascular event, or graft thrombosis occurred in 9.9% of patients, who were followed-up for a mean of 4.8 months. No significant overall correlations were found between APCR and thrombotic morbidity. Subgroup analysis revealed significant associations between functional APCR and total early postoperative thrombotic complications and early graft failure, and between factor V (Leiden) and early cerebrovascular events and late graft thrombosis (p < 0.03).Conclusions: Functional APCR is somewhat more prevalent among general vascular surgical patients than in the general population, but factor V (Leiden) is no more prevalent. APCR is not a prominent cause of thrombotic morbidity in contemporary vascular surgery. Nonetheless, it is a sufficiently important potential contributor to morbidity among some subgroups to warrant selective testing and directed therapy pending further study. (J Vasc Surg 1997;25:1054-60.)     

Flow-independent angiography for peripheral vascular disease: Initial in-vivo results

Flow-independent angiography (FIA), an approach that isolates arterial blood using MR relaxation characteristics rather than flow effects, was evaluated for application in peripheral vascular disease (PVD). First, pilot studies were conducted in which FIA coronal projection images were obtained from controls and symptomatic patients with PVD to assess clinical utility. All control images corresponded to the expected leg arterial anatomy with little interference from deep veins (one of five) and muscle (zero of five). Superficial venous signal was less well suppressed in comparison to deep veins (four of five). Images of symptomatic patients were less consistent with difficulty suppressing muscle and deep venous signal in some cases and edema when present. We then compared T2 values for muscle (T2_m, tibialis anterior), arterial blood (femoral and popliteal arteries), and venous blood (femoral, popliteal, and saphenous veins) in controls (n = 8) and symptomatic patients with intermittent claudication (n = 5) or ischemic rest pain (n = 7). Changes in T2 measurements of various tissues accounted for poorer contrast in symptomatic patients. Patients with ischemic rest pain had significantly higher T2_m compared with controls (T2_m = 39.3 ± 2.1 (1 standard error of the mean [SEM]) versus 30.9 ± .4, P < .01). For all measurements, other than saphenous vein, variances were greater in symptomatic patients. To realize the inherent advantages of FIA for this clinical application, additional work on suppression of signals from muscle, veins, and edema is required. One promising approach involves shifting from projection images to three-dimensional acquisitions for improved tissue suppression.     

Detection of local recurrence of soft-tissue sarcoma with positron emission tomography using [18F]fluorodeoxyglucose

Background: It is often difficult to detect a local recurrence of soft-tissue sarcomas due to disturbance of the normal anatomy by previous surgery and radiotherapy. The aim of this study was to assess the value of positron emission tomography (PET) with [¹⁸F]fluoro-2-deoxy-d-glucose (FDG) for detecting local recurrences. Methods: In the period 1992–1995, 17 patients with proven or suspected local recurrence of soft-tissue sarcoma were examined using FDG-PET. Fifteen of these patients were ultimately proven to have a recurrence. Results: Recurrence was visualized in 14 patients (93%). Small tumors (maximum diameter 0.5 cm) were as easily visible as large lesions (maximum diameter 20 cm). In one patient the PET scan was positive, but the recurrence could not be proven histologically. Recurrence was proven 1 year later. A recurrent low-grade liposarcoma was not visualized. The two patients with benign lesions had a negative PET scan. The mean glucose metabolic rate was calculated to be 13.2 μmol/100 g/min (range 1.9–28.4). A correlation was found between the histological malignancy grade and the metabolic rate (p<0.05; Kruskal-Wallis). Conclusion: PET with FDG is a useful addition to the diagnostic armamentarium for detecting local recurrence of soft-tissue sarcomas and provides an indication of the malignancy grade of the recurrent lesion. Presented at the 47th Annual Meeting of The Society for Surgical Oncology, Houston, Texas, March 17–20, 1994.     

Therapeutic options for severe, refractory status asthmaticus: inhalational anaesthetic agents, extracorporeal membrane oxygenation and helium/oxygen ventilation

Despite improvements in supportive care, the mortality and morbidity of asthma remain constant. The risks and incidence of morbidity related to barotrauma remain high in patients that require mechanical ventilation. The authors present three alternative strategies including the inhalation of anaesthetic agents, helium/oxygen ventilation, and extracorporeal membrane oxygenation which may be beneficial when 'conventional therapies' fail in the intubated patient with status asthmaticus.     

A randomized controlled trial of sedation in the critically ill

A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children.     

Arthroscopic capsulorrhaphy formultidirectional instability

Multidirectional shoulder instability is a common affliction and is increasingly recognized as a debilitating condition in young, athletic patients. Most patients with this condition are in their third decade and have a history of macrotrauma or repetitive microtrauma. Complaints range from frank instability to instability with pain, or to pain alone. These patients may display clinical signs of instability, impingement, or both on physical examination. Generalized ligamentous laxity or shoulder laxity alone are usually present. A positive sulcus sign remains the most sensitive clinical test in distinguishing these patients, even though no data is available on the sensitivity or specificity of this examination. The greater majority of patients are successfully treated with an exercise program stressing rotator cuff and scapular stabilizer strengthening. When patients do not respond to conservative treatment, open capsular shift has been recommended to restore joint stability. Early successes with the arthroscopic treatment of anterior shoulder instability have led to the development of similar procedures for the treatment of multidirectional instability. This paper describes an arthroscopic, multiple suture capsulorrhaphy for the treatment of multidirectional shoulder instability, which is a modification of the procedure advocated by Caspari and reviews the 2-year results of the first 19 patients treated.     

Iodine status in vegans consuming a living food diet

The dietary intake and urinary output of iodine and the thyroid activity was measured in 12 living food eaters (people consuming uncooked, Lactobacilli rich vegan food) and omnivores. Seven day food record was used for calculating the dietary iodine intake, instrumental neutron activation analysis for measuring the urinary iodine output and RIA for determining of the thyroid hormones (TSH and FT4). The living food eaters were divided into two groups according to urinary iodine output: high iodine group (≥900 ug/d) and low iodine group (<200 ug/d). Thyroid activity in both groups was with in normal range. Dietary intake of iodine was dependent on the the use of seaweed. The highest amounts of dietary iodine observed in the present study, as assessed by the the urinary iodine output, can be harmful for susceptible subjects. On the other hand the calculated intake of iodine by living food eaters didn't fill the RDA. As an conclusion on a living food diet one has to ensure the sufficient intake of iodine by consuming seaweed or Kelp tablets daily. However the intake of these preparations needs to be kept at reasonble limits due to their possible high iodine content. More information of the iodine content of different seaweeds and seaweed products is needed.