The Effect of Probe Position, Calf Muscle Function and Lipodermatosclerosis on Photoplethysmographic Venous Refilling Time

Objective:

To assess the influence of probe position, lipodermatosclerosis and method of calf muscle emptying on the venous refilling time as measured by photoplethysmography in both normal limbs and limbs with chronic venous disease.

Design:

Prospective evaluation of age- and sex-matched control and study groups.

Setting:

University Department of Surgery, Vascular Research Laboratory, Fremantle Hospital, Western Australia.

Patients:

There were 38 controls and 31 patients with venous ulceration.

Interventions:

Venous refilling times were measured in six positions on the leg in all subjects: the foot, 5 cm below medial tibial condyle in the upper calf, and in the gaiter region on the medial, lateral, anterior and posterior positions at 7.5 cm above the medial malleolus. Measurements were undertaken on active exercise and after bimanual calf compression in the medial gaiter region. Measurements were also undertaken in areas of lipodermatosclerotic skin and in normal-appearing adjacent skin.

Results:

In normal legs, the lowest refilling times were in the anterior and lateral gaiter positions. Venous patients had a shorter refilling time in the dorsal foot, medial gaiter, posterior gaiter and medial below-knee positions, when compared with controls (Mann–Whitney U-test, p<0.01). The shortest refilling time in patients with venous disease was in the medial gaiter region. Refilling time was slightly prolonged over Hpodermatosclerotic skin compared with adjacent normal-looking skin. Refilling time measured after passive emptying of the calf muscle by external compression was significantly prolonged compared with calf emptying by active calf compression ( p<0.01). This change was similar for both groups.

Conclusions:

When using venous refilling time on photoplethysmography to distinguish venous from normal limbs, the best separation is in the medial gaiter position. If other probe sites or methods of calf emptying are to be employed, it is imperative that individual laboratory normal ranges be established for the particular method being employed.

Epidemiology of spinal cord injuries in the 2005 Pakistan earthquake

STUDY DESIGN

Prospective observational study.

OBJECTIVES

To identify the epidemiological features specific to spinal injuries as a result of an earthquake.

SETTINGS

Rawalpindi, Pakistan in the months after the 8 October 2005 earthquake.

METHODS

In the month after the earthquake, the one established rehabilitation center was augmented with two makeshift spinal cord centers. Information on mechanism of injury, mode of evacuation, associated injuries was gathered, and a detailed clinical and radiological assessment was performed. Neurological status and functional outcome was determined after 10 weeks.

RESULTS

Of an estimated 650-750 spinal cord injuries, 187 were admitted to these centers, including 80 men and 107 women with a mean age of 28.3+/-12.4 years. Injuries occurred while standing in 57.8% of patients. Most (83.4%) who reached the spinal cord center were airlifted. A urinary catheter had been placed before admission in 91.5%. Most of the patients were paraplegic 89.3, with 50.8% incomplete injuries. Fracture or fracture dislocation was present in 70, and 75% underwent spinal fixation. Although pressure ulcers (28.9%) and urinary tract infections (39%) were common, deep venous thromboses (4.8%) and depression (5.8%) were seldom detected. At 10 weeks, 75% were continent or performing intermittent catheterization. There were no deaths and two births.

CONCLUSION

After a disaster, evacuation of persons with a spinal cord injury to a specialized center results in low mortality. Response planning for disasters should include early aggressive medical rehabilitation.

The influence of dressings on venous ulcer healing--a randomised trial

OBJECTIVE

To assess the effect of different dressings on venous ulcer healing.

DESIGN

A randomised clinical trial.

MATERIALS

Patients were randomised to treatment with one of three dressings: a zinc oxide impregnated bandage, a zinc oxide impregnated stockingette, or an alginate dressing. All patients were treated as outpatients and had compression bandaging with two minimal stretch bandages (Elastocrepe) and a stockingette (Tubigrip) to keep the bandages in place.

METHODS

One hundred and thirteen patients (133 ulcerated limbs) with chronic ulceration of the leg due to venous disease alone, and attending Fremantle Hospital Leg Ulcer Clinic, Western Australia were entered into the study. Healing was measured as complete healing of the ulcerated limb or failure of the limb to heal within 9 months.

RESULTS

There was no significant difference between the three groups in ulcer size, duration, and other parameters compared. Healing was affected significantly by ulcer size and which leg was ulcerated. There was significantly faster healing with the paste bandage.

CONCLUSION

The use of a paste bandage significantly improved the healing of chronic venous ulcers when used in combination with compression bandaging, and compared to an alginate dressing and a zinc oxide impregnated stockingette.

Influence of arterial disease, age and active ulceration on venous refilling time measured by photoplethysmography

This study investigated the influence of arterial disease, patient age and the presence of a venous ulcer on venous refilling time as measured by photoplethysmography. Refilling time was evaluated in 157 control limbs, in 133 limbs with venous disease, in 17 limbs with arterial disease and in 20 limbs with mixed disease (arterial and venous disease) as the cause of ulceration. Refilling time reduced progressively with age in control subjects and was significantly shorter over the age of 50 years. Limbs with venous disease alone had a significantly shorter refilling time when compared with controls (Mann-Whitney U test, P < 0.01); however, there was no alteration in refilling time with age. Limbs with arterial disease, without clinical evidence of venous insufficiency, had a shorter refilling time when compared with controls but a longer refilling time compared with those with venous disease (P < 0.01). The refilling time in patients with mixed ulcers did not differ from those with venous ulcers (P < 0.265). Refilling time measured when an ulcer was present was not significantly different to that measured after the ulcer had healed (P = 0.59). Venous refilling time normally reduces with age but is not affected by arterial disease or the presence of an ulcer.

Treatment of acute duodenal ulcers with famotidine and its comparison with other H2 blockers

Famotidine, a new H2 antagonist in a dose of 40 mg qhs was tried in a clinical trial for the treatment of duodenal ulcer in 25 patients and compared with other H2 antagonists. Cimetidine 800 mg qhs and Ranitidine 300 mg qhs were used in a similar number of randomised patients. Patients were evaluated clinically, biochemically and endoscopically. At the end of eight weeks, the healing rate with Famotidine was 96%. Cimetidine was 92% and Ranitidine 96%. No significant side effects were noted with any of these drugs. In conclusion, Famotidine (40 mg qhs) is an effective and generally well-tolerated drug in the treatment of acute duodenal ulcer.

Insulin-like growth factor (IGF)-binding protein release by human fetal fibroblasts: dependency on cell density and IGF peptides

Insulin-like growth factors (IGFs) are bound to specific binding proteins in extracellular fluids in vivo and when released by cells in vitro. One class of binding protein (IGF-BP), a peptide of 26 kDa purified from amniotic fluid, has been shown to modulate IGF bioactivity on isolated human fibroblasts. We have determined the factors that control release of IGF-BP from monolayers of human fetal fibroblasts using a radioimmunoassay, and have compared this with the effects of these factors on the release of IGF-I and -II. Separation of cell-conditioned cultured medium on SDS-PAGE, and subsequent immunoblotting with antibody against IGF-BP showed that fibroblasts released a single species of immunoreactive protein of an estimated molecular weight of 30 kDa. This was not the predominant binding protein released by cells since major bands of approximately 42 kDa and 39 kDa were visualized following separation by SDS-PAGE and ligand blotting with 125I-labelled IGF-I. The 30 kDa IGF-BP was released in parallel with radioimmunoassayable IGF-I and -II over 48 h. However, a significant inverse correlation was found between the release of IGF-BP, IGF-I, IGF-II and cell density. The exposure of fibroblasts to 1.3 nmol/l or greater of IGF-I or -II caused a significant release of IGF-BP. Maximum release was seen in sparse cultures with little or no release from confluent cultures. IGF-I and -II were approximately equipotent with a fourfold increase in IGF-BP release at 19.7 nmol/l. Insulin caused a release of IGF-BP and IGF-I and -II from fibroblasts at supraphysiological concentrations (16.7 nmol/l) which again was maximal on sparse cell cultures. Increases in IGF-BP, IGF-I and -II release were also found in the presence of human placental lactogen (23.3 nmol/l), but human GH, epidermal growth factor, fibroblast growth factor and platelet-derived growth factor were without effect. The results show that human fetal fibroblasts released an IGF-BP immunologically similar to that seen in amniotic fluid together with IGF-I and -II, that IGF-BP release was enhanced by exogenous addition of IGF peptides, and that the release of all three peptides was a property of sparsely plated, rapidly growing cells. These findings strengthen the hypothesis that the cellular expression of IGF-binding proteins may represent an important level of control in IGF physiology.