Experience with the Amplatz retrievable vena caval filter. Work in progress

The Amplatz retrievable vena caval filter was designed in an attempt to decrease complications associated with the placement of Mobin-Uddin or Kimray-Greenfield filters. The design allows percutaneous retrieval, thus expanding application of the filter to situations requiring temporary prophylaxis against pulmonary embolism. Filters have been placed in 16 patients, nine (56%) for prophylactic purposes. All filters were easily inserted percutaneously. Complications occurred in three patients; these included complete thrombosis of the inferior vena cava below the filter, misplacement of one filter into the pericaval retroperitoneal tissue, and development of thrombus cranial to the filter. With the current introduction system, the possibility of filter misplacement has been essentially eliminated. No patient experienced symptoms suggestive of pulmonary embolism after filter insertion. One filter retrieval has been performed, with no complications.     

Effect of medial arch-heel support in inserts on reducing ankle eversion: a biomechanics study

Background  

Excessive pronation (or eversion) at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running.     

Effects of saliva contamination and phosphoric acid composition on bond strength

The purpose of this study was to determine the effects of a phosphoric acid gel and solution, and saliva contamination of etched enamel on the tensile bond strength (TBS) of a posterior composite resin to etched enamel. Ninety-six extracted human permanent maxillary canines were used in this study. The test system developed by Kemper and Kilian was used to determine the TBS of a posterior composite resin (P-10) to enamel. The ground enamel surfaces were etched with 37% H₃PO₄ gel for 60 sec and washed for 15 sec or 30 sec, and with 37% H₃PO₄ solution for 60 sec and washed for 15 sec or 30 sec, respectively. The ground enamel surfaces were also etched with H₃PO₄ gel for 60 sec, washed for 15 sec and rewashed for 15 sec after saliva contamination of the etched enamel for 15 sec, 60 sec and 60 min, respectively. Etched enamel surfaces contaminated with saliva for 15 sec were re-etched for 15 sec and washed for 15 sec. The test specimens were mounted in an Instron machine and subjected to a tensile load at 0.02 inch. min⁻¹. The force required to break a test specimen was recorded, and the bond strengths were calculated and expressed in MN.m⁻². The data were analyzed by ANOVA and Duncan's multiple range test at the 5% level of significance. The H₃PO₄ composition (gel vs solution) and wash times had no significantly different effect on TBS. Only a 60 min saliva contamination significantly reduced TBS. In this study the TBS was determined 24 h after specimen preparation. It is possible that salivary contamination of etched enamel may have an adverse effect on bond strength only after prolonged immersion of the test specimens prior to testing.     

Multiple pterygium syndrome: a case complicated by malignant hyperthermia

The autosomal recessive multiple pterygium syndromes are a heterogeneous group of disorders in which multiple joint contractures are associated with cutaneous webbing. Recently, we evaluated a 33 week gestation male in whom multiple pterygia were one feature of a broader pattern of malformation. Clinical management was adversely affected by malignant hyperthermia. In this report we present the clinical, radiographic and pathologic data of this patient and those of an affected stillborn female sibling. We believe that these represent the features of a newly recognized disorder.     

The controversy surrounding epilepsy and Driving: Areview

Both medical literature and the law relating to epilepsy and driving have beenreviewed. The review has concentrated mainly on the UK but has drawn on overseas experience where this is relevant. The law takes a simplistic view and there is no significant legal precedent to guide either current or future judgements. Medical advice is not particularly helpful because of the self-contrialists and conflict of advice between groups of specialists.     

Simultaneous bilateral hernia repair. A case against conventional wisdom.

The timing of bilateral hernia repair remains controversial. Because of reported high recurrence rates after simultaneous bilateral repair, staged procedures have been suggested. This study determined recurrence and complication rates of unilateral versus simultaneous bilateral repair. Of 659 patients undergoing hernia repair between 1974 and 1980, 333 underwent unilateral repair and 329 had simultaneous bilateral repair. More than 90% of patients were followed until death or a minimum of 60 months (median, 104 months). Perioperative complications were associated with 18% of repairs. More morbidity occurred in the bilateral group. However complication rates for specific events were not significantly different, except for urinary retention, which occurred in 20 patients (6.1%) of the unilateral group and 49 (15%) of the bilateral group (p less than 0.001). Overall 25 recurrences occurred in the unilateral group and 31 in the bilateral group. Recurrence rates at 5 and 9 years were, respectively, 4.8% and 8.8% in the unilateral group and 5.0% and 9.1% in the bilateral group (p = 0.861). These data suggest that simultaneous bilateral inguinal herniorrhaphy does not result in increased rates of most postoperative complications or recurrence when compared with unilateral repair.     

Ultrasonic exposure modifies platelet morphology and function in vitro

Samples of human platelet rich plasma (PRP) exposed to 1 MHz ultrasonic irradiation contained more cellular debris than their controls, indicating that a small population of the cells had been disrupted, possibly by some form of cavitation-like activity. The surviving cells appeared undamaged under the electron microscope and functioned as well as their controls in forming a platelet thrombus when tested immediately after the ultrasonic exposure but not after a 30 min incubation at 22°C. Parallel studies showed that incubation of control platelets with substances released from damaged or disrupted platelets could mimic the changes seen in incubated samples which had previously been exposed to ultrasound.     

EFFICACY OF RAMIPRIL VERSUS ENALAPRIL IN PATIENTS WITH MILD TO MODERATE ESSENTIAL HYPERTENSION

SUMMARY This double-blind, randomised, cross-over study investigated the antihypertensive efficacy of ramipril and enalapril was completed by 30 patients with mild-to-moderate essential hypertension. After a four-week placebo run-in phase, the patients received either 2.5mg ramipril or 10mg enalapril once daily for four weeks. The dosages were increased to 5mg ramipril and 20mg enalapril for a further four weeks. After a placebo washout phase of four weeks, the patients were crossed over to the alternative treatment. The decrease in average 24-hour ambulatory diastolic blood pressure from week 0 to week 8 was 1.6mmHg greater with ramipril than enalapril (90% confidence interval 0.6-2.7mmHg). The corresponding reduction in for systolic blood pressure was also greater with ramipril than enalapril by 2.4mmHg (90% confidence interval: 0.5-4.2mmHg). For the difference in the drop of 24-hour ambulatory diastolic blood pressure between ramipril and enalapril the lower level of the 90% confidence interval (CI) is above the clinically relevant difference of -3mmHg. This is an indication that ramipril (2.5 and 5mg dose) is at least as effective as enalapril (10 and 20mg dose) in decreasing blood pressure in patients with mild-to-moderate essential hypertension. The duration of adequate antihypertensive effect was relatively long for both ramipril and enalapril; however, ramipril tended to have a more prolonged antihypertensive effect. Ramipril had a higher diastolic and systolic trough/peak ratio than enalapril, resulting in a more uniform antihypertensive effect over the 24-hour treatment period. Both ramipril and enalapril were well tolerated and the two treatment groups had similar safety profiles.