USE OF THERMOTHERAPY IN MANAGEMENT OF LYMPHEDEMA: CLINICAL OBSERVATIONS
Campisi C, Boccardo F, Tacchella M
Int J Angiol 1999; 8:73-75


ABSTRACT AND COMMENTARY BY:
Prof. Micha? F?ldi
Fachklinik f‘A Lymphologie
R?(TM)lehofweg, Germany


The authors report 67 patients suffering from primary and secondary lymphedema of the limbs treated by heat and humidity without applying elastic compression. They regard their technique of hyperthermia as an alternative to microwave therapy. They produce a hot and humid ambience in a chamber inside of which the limb is situated. They report improvement both in function of the limbs and volume of lymphedema.

The patients were followed six months to one year after the end of treatment. The authors state following 12 cycles there was an almost absent risk of lymphangitis for one to three years. I was astounded to find in Figure 3 that mean volumetric evaluation of peripheral lymphedemas was done in patients treated by thermotherapy and microsurgical operations (67 patients). Nowhere in the text does it state that thermotherapy was combined with microsurgical operations. Moreover, according to the figure, the observation period lasted for five years. No standard deviations are given and the authors do not mention that they performed a statistical analysis.

COMMENTARY

In 1984, Chang et al. reported successful use of an electrocontrolled infrared ray heating chamber for the treatment of chronic lymphedema of the extremities in over 1000 patients since 1964.1 After each heat treatment, elastic bandages were applied. In 1983, these Chinese authors used a microwave heating apparatus. In 1992, they published a series of 40 patients treated by this apparatus in combination with elastic bandages.2 Both circumference and volume showed a statistically significant reduction. In 1996, Gan et al. reported on the treatment of 45 patients suffering from post mastectomy lymphedema by using microwave heating.3 After two courses of treatment, reduction in lymphedema was statistically significant, the incidence and severity of erysipelas attacks were sharply reduced, and the elasticity of tissues was restored.

Fox and Lanzetta applied thermotherapy by an electromagnetic wave chamber in combination with elastic stockings.4 In 1989, Fox et al. reported treatment of 107 patients suffering from lymphedema of the limbs with a 79.6% success rate.5 In 1993, Liu and Olszewski reported treatment of lymphedema by thermotherapy applied either by microwave heating or by hot-water bath in combination with compression bandages.6 The girth and the volume of the limbs decreased significantly in both groups. Lymphoscintigraphy did not show any alteration in dermal backflow or speed of the tracer transport velocity before and after treatment. Histologically, lymphedematous skin after heat treatment showed a near resolution of perivascular cellular infiltration and the disappearance of lymph lakes.

In treating lymphedema, adequate prospective, randomized studies need to be performed in order to establish the possible role of various forms of treatment, alone or in combination. These forms of treatment include compression, complex decongestive physiotherapy, and/or microsurgery. There are several methods of microsurgery and standardization should be mandatory as well. ivdffol1


REFERENCES

1. Chang TS, Huang WY, Han LU, Liu WY. Heat and bandage treatment for chronic lymphedema of extremities. Chinese Med J 1984; 97:567-77.

2. Chang TS, Gan JL, Huang WY, Liu W, Fu KD. A modified microwave oven in the treatment of chronic lymphedema of the extremities. Eur J Plast Surg 1992; 15:242-46.

3. Gan JL, Li SJ, Cai RX, Chang TS. Microwave heating in the management of post mastectomy upper limb lymphedema. Ann Plast Surg 1996; 36:576-80.

4. Fox U, Lanzetta M. Microsurgery and thermotherapy for chronic limb lymphedemas. In: Progress in Lymphology XII . Excerpta Medica, Amsterdam, New York, Oxford 1990.

5. Fox U, Romagnoli G, Ribaldone G, Montorsi W. La microchirurgie et les therapies associees pour le traitement des lymphoedemes des membres. J des Maladies Vasculaires 1988; 13:125-29.

6. Liu NF, Olszewski W. The influence of local hyperthermia on lymphedema and lymphedematous skin of the human leg. Lymphology 1993; 26:28-37.






PRINCIPLES OF SURGICAL TREATMENT OF CHRONIC LYMPHEDEMA
Gloviczki P.
Int Angiol 1999; 18:42-46


ABSTRACT AND COMMENTARY BY:
Prof. Micha? F?ldi
Fachklinik f‘A Lymphologie
R?(TM)lehofweg, Germany


It is very good that Dr. Gloviczki, Head of the Division of Vascular Surgery at one of the world's most prestigious clinics, expresses his opinion about principles of the surgical treatment of lymphedema. However, his reservations in judgment of lymphedema surgery show clearly. According to Partsch et al., 75 different techniques of operative treatment of lymphedema have been described.1 It is noteworthy, therefore, that at the Mayo Clinic, only 14 patients had lymphovenous shunt operations and that, 46 months after surgery, a relapse had occurred after temporary improvement in nine patients.

COMMENTARY

At the 1998 World Congress for Phlebology held in Sydney, Australia, Olszewski, who inaugurated the technique of lymphovenous shunts in the 1960s, reported that only 112 such operations are performed worldwide per annum. This shows that in spite of enthusiastic sporadic reports from Italy, Holland, China, and Australia, the creation of lymphovenous shunts cannot be regarded as an established procedure. Baumeister, who introduced his technique in the 1980s, performs it only once a month.

According to Gloviczki, a potential indication for operative treatment for lymphedema is if medical management has failed. Unfortunately, the term medical management is not clarified. Administration of diuretics, elevation of the lymphedematous limb, intermittent compression (pneumomassage), etc., are considered medical management and are doomed to failure. Complex decongestive physiotherapy (CDP), the method of choice for lymphedema treatment, is highly effective even in elephantiasis provided it is performed skillfully with adequate patient compliance. Removal of empty skin sacs which often evolve after CDP may be a relative indication for surgery. CDP abolishes episodes of cellulitis and lymphangitis which means that these conditions are not criteria for surgery. Intractable pain does not occur in pure uncomplicated lymphedema, even in elephantiasis.

With regard to the unwillingness of the patient to undergo further conservative treatment, Trevidic et al. has shown that the majority of patients who have been unhappy with the result of a first series of CDP could be persuaded to try it again and are more satisfied with the second series performed by more experienced physiotherapists.2 On the other hand, the majority of patients who were treated by surgery had unsatisfactory results.

This reviewer agrees with Gloviczki that "prolonged hospitalization, poor wound healing, long surgical scars, sensory nerve loss, residual edema of the foot and ankle, and poor cosmetic results are significant problems and prevent the offering of such procedures." However, I disagree with the view that cases of "truly disabling lymphedema, not responding to medical measures" should be operated. In first-world countries where CDP should be available for every patient, debulking operations should not be considered. ivdffol2


REFERENCES

1. Partsch H, Rabe E, Stemmer R. Kompressionstherapie der Extremit?ten. Editions Phlebologiques Francaises, 1999.

2. Travidic P, et al. Indications of surgery in patients with lymphedema: Toward a multidisciplinary unit of decision. Lymphology 1998; 31(Suppl):566-69.








A SOCIOECONOMIC STUDY OF THE DIFFERENT PRINCIPLES OF TREATMENT OF VENOUS ULCERS: PRELIMINARY RESULTS (in French)
L?y E.
J des Maladies Vasculaires 1998; 23:277-81


ABSTRACT AND COMMENTARY BY:
Reinhard Fischer, M.D.
St. Gallen, Switzerland


This paper describes a prospective study enrolling 800 physicians with 1600 patients with venous ulcers. The purpose was to analyze the costs and benefits of treatment of ulcers of venous origin. In this preliminary report, Levy defines the involved groups of physicians, patients, and ulcers as well as the different types of treatments which were initiated. The parameters were determined at the screening examination of the first 247 patients.

With regard to physicians, 86.5% were general practitioners and 13.5% were specialists from all parts of France. One-fourth of these were dermatologists and three-fourths were angiologists. Considering the patients, three-fourths were women of an average age of 72 years. Only 10% were working age. Twenty percent (20%) of the women and 25% of the men had come to medical attention for other reasons. The nonworking patients received treatment at home but if treated in the office, one in three patients needed to be accompanied by a person absent from work to take them. Of the patients seen, 25% had edema, 95% had varicose disease, 60% had arthritis, 60% had hypertension, and 30% had cardiac disease. One in two patients had received previous ulcer treatment. The average maximum ulcer diameter was 3.5 cm at the time of presentation.

Treatment consisted of cleansing initiated in 99%, compression therapy in 64%, antibiotics in 11%, anticoagulation in 13%, antiaggregation agents in 13%, local antibiotics in 26.5%, and other local treatment in about 50%. Sclerotherapy and/or surgery was done in 2.5% of patients with ulcer. In general, most physicians appeared to use several modalities simultaneously. General practitioners tended to use general treatment while specialists tended to stress compression.

COMMENTARY

In this preliminary report, we learn about the concept of this upcoming comprehensive study as well as the prevalence of physicians, patients, and treatment groups. Of course, at this early time, we do not learn anything yet about the cost, duration of treatment, and rate of healing. However, this report yields one fact: General practitioners seem to rely more on general treatment and specialists assign much importance to compression. This is absolutely in line with my own experience. It is my impression that this is because general practitioners are, on average, less trained in compression therapy and therefore will rely less on this important feature of ulcer treatment.

It is my hope that the author will successfully finish this ambitious study because it will add to our knowledge about the costs and benefits in the treatment of venous ulcers. ivdffis






EXPRESSION OF TISSUE-TYPE AND UROKINASE-TYPE PLASMINOGEN ACTIVATOR ACTIVITIES IN CHRONIC VENOUS LEG ULCERS
Rogers AA, Burnett S, Lindholm C et al.
VASA 1999; 28:101-105


COMMENTARY BY:
Prof. Bengt Fagrell
Stockholm, Sweden


In this study, the changes in proteinase activity within and surrounding chronic venous ulcers has been studied in relation to the pathology of the ulceration. It has been shown earlier that chronic wounds exhibit elevated proteinase activity, and it has been suggested that these high levels of proteinase may play a role in ulcer formation and the nonhealing nature of ulcers. The aim of the study was to examine the expression of plasminogen activator (PA) activity in chronic venous ulcer tissue in comparison to all involved skin using the technique which spatially resolves PA activity.

A total of 22 patients (10 women, 12 men) with therapy-resistant venous leg ulcers were studied (mean age 75.5 years). Ulcers had been present for approximately 28 (!) years with a duration of the present ulcer in the study of approximately four years. Punch biopsies of 2 mm were taken from three sites in each patient. Histological zymographic technique for PA was used to evaluate PA activity. Semiquantitative evaluation of PA activity expression was also done using a scoring system by two independent double-blind investigators.

There was a progressive increase in total proteinase activity. This ranged from a low level in uninvolved skin to an intermediate level of activity in skin adjacent to the ulcer to a high level of proteinase activity seen in the ulcer base biopsies. The expression of urokinase-type PA (uPA) and tissue-type PA (tPA) in the ulcers was also examined by comparing slides showing total proteinase activity with slides having specific inhibitors present in the overlay. The research was able to examine the contribution to the total proteinase activity made by uPA and tPA. Biopsies from uninvolved skin (thigh skin) suggested that the main PA was tPA and that there was little or no uPA activity. Biopsies from skin immediately adjacent to the ulcer base showed a different pattern where uPA seemed to be the predominant activity. The ulcer base biopsies suggested an apparent ulcer-specific plasminogen-independent proteinase activity. This has also been detected in pressure ulcer tissue.

COMMENTARY

This is a very nice study showing that proteinase activity is somewhat different in skin of chronic venous ulcers compared to normal skin. The patient group consisted of patients with therapy-resistant venous leg ulcers and mean ulcer duration of 28 years. It is rather surprising to me that ordinary venous ulcers cannot be healed since, in my experience, they usually do heal with firm and correct compression therapy.

One must ask about the arterial circulation in these rather elderly patients (mean age 75 years). If there was a reduced arterial circulation to the legs, this would, of course, influence the results achieved. One must also ask about the activity of PA in the chronic venous ulcers which showed a healing tendency. If the changes seen in the present patients were altered during the healing process of the ulcers, this would indicate that PA activity might be an important factor in the healing of venous ulcers.

The conclusion that there is a specific difference in location and type of PA between ulcers and normal skin is, of course, justified but the role these differences play in the healing process is not yet solved. However, as the authors suggest, these differences may play a role in the changes in fibrinolytic status of the vasculature and level of tissue activation seen in chronic venous ulceration. ivdffag2








DOES ORAL ZINC AID THE HEALING OF CHRONIC LEG ULCERS?
Wilkinson EAJ, Hawke CI
Arch Dermatol 1998; 134:1556-60


COMMENTARY BY:
Prof. Giuseppe M. Andreozzi
Prof. M. A. Scomparin
Padua, Italy


Leg ulcers affect about 1% of the population. They are frequently caused by a variety of diseases: Chronic venous insufficiency, peripheral arterial disease, diabetes, and rheumatic disease. Treatment is not completely defined. Treatment needs to address the pathophysiology of each disease but different approaches have been suggested in local and systemic management. One of these is the administration of zinc sulfate. A randomized trial suggests that zinc sulfate is able to reduce the time of healing by 43%. Zinc is a trace element necessary for some enzyme and hormonal function but it also has anti-inflammatory effects. Zinc insufficiency correlates with slow wound healing and susceptibility to infections.

This article, which follows the Cochrane Wounds Group Selection Criteria, reviews some trials, controlled and uncontrolled, which used zinc in the management of leg ulcers. Six studies were selected. Treatment duration, followup, and ulcer characteristics were not uniform. Etiology was not a determinant for treatment. The principal target was the healing time and/or reduction to at least 50% of baseline. Initial diameter was also not a selection criterion.

The absence of selection criteria make the explanation of results difficult. Chronic venous insufficiency ulcers did not show any difference between zinc and placebo groups.1-3 Hallbrook4 did not find any difference between the two groups but his study notes a faster healing rate in a subgroup of treated patients with lower plasma levels of zinc. The difference is not significant statistically. The hypothesis of efficacy of zinc treatment in patients with low plasma levels was not considered during the study design and this could be important in future studies. Haeger5 found that a low plasma level correlates with faster healing but he did not find any difference between the treated group and the placebo group.

COMMENTARY

We agree with the meta-analysis of the authors regarding the difficulty in drawing definite conclusions on the use of zinc sulfate in the treatment of leg ulcers. There is not enough evidence to show that oral zinc sulfate is beneficial in promoting ulcer healing. Some positive results have been described in patients with a low baseline plasma level. However, more studies are needed. From the selected studies, we cannot decide anything about the duration of therapy or dose of the drug. The authors emphasize that more studies are needed to verify the efficacy of treatment and they stress the role of a low baseline plasma level of zinc.

From a clinical point of view, we add that pathogenesis and pathophysiology of diabetic ulcers is very different from chronic venous insufficiency ulcers, or rheumatoid or arterial for that matter. Future studies must select rigorously the diagnosis of causation of the ulcer to avoid all confusion. Regarding chronic venous insufficiency, we suggest distinguishing not only the pathogenesis and pathophysiology (CVI from varicose veins or from postthrombotic syndrome) but also between hemodynamic and anatomic (obstruction and/or reflux in axial veins or perforators) using the CEAP classification. In these patients, an eventual trial should normalize hemodynamics in treatment with occlusive compression of reflux.

This procedure is well known to angiologists and phlebologists and is able to reduce, by itself, the healing time of venous ulcer.6 The efficacy of support treatment can be assessed only by normalizing the hemodynamic abnormalities. The lack of normalization of the population study, with treatment of reflux is, in our opinion, an important mistake. The selection of studies for the meta-analysis has been rigorous. Nevertheless, the small number of dated studies (20 years old) should suggest that the analysis should not have been performed.

Some recent studies suggest that the way to evaluate the effectiveness of zinc therapy in ulcer healing is to consider the pathophysiology and not just do a trial. The role of zinc in the pathogenesis and pathophysiology of cutaneous ulcers is still not clarified. More recent studies note that the cutaneous level of zinc, measured in vivo with spectroscopy, is higher in varicose ulcer than in undamaged skin.7 Finally, topical administration of zinc seems to give better results than oral therapy. Its effectiveness seems to be due to local antibacterial activity with reduction of superinfections augmented by an indirect activation and improvement of local defense systems.8 ivdfand1


REFERENCES

1. Haeger K. Oral zinc sulfate in the treatment of chronic leg ulcers. VASA 1972; 1:62-65.

2. Philips A. Venous leg ulcerations: Evaluation of zinc treatment, serum zinc, and rate of healing. Clin Exp Dermatol 1977; 2:395-99.

3. Graeves MW. Double-blind trial of zinc sulfate in the treatment of chronic leg ulceration. Br J Dermatol 1972; 87:632-634.

4. Hallbrook T. Serum zinc and healing of venous ulcer. Lancet 1972; 2: 780-82.

5. Haeger K. Oral zinc sulfate and ischemic leg ulcers. VASA 1974; 3:77-81.

6. Brandrup F. A randomized trial of two occlusive dressings in the treatment of leg ulcers. Acta Derm Venerol 1990 70(3):231-35.

7. Ackerman Z. Skin zinc concentration in patients with varicose ulcers. Int J Dermatol 1990; 29(5):360-62.

8. Agren MS. Studies on zinc in wound healing. Acta Derm Venereol 1990(Suppl); 154:1-36.








STRUCTURAL CHANGES OF THE CRURAL FASCIA IN PATIENTS WITH ADVANCED CHRONIC VENOUS INSUFFICIENCY AND CHRONIC, RESISTANT-TO-THERAPY VENOUS ULCERS (in Polish)
Staubesand J, Li Y
Przeg Fleb 1998; 6(1):5-22


ABSTRACT AND COMMENTARY BY:
Prof. dr. hab. med. Zygmunt Mackiewicz
Professor of Surgery
Head, Department of General & Vascular Surgery
Bydgoszcz, Poland


The aim of this article is to compare structural changes of the crural fascia of 27 patients with chronic venous insufficiency (CVI) with 24 subjects with healthy veins. The structural changes were investigated by electron microscopy. In a sample of 24 subjects with healthy veins, the collagen fibrils in the superficial layer of the crural fascia were arranged strictly in bundles running in various directions in space. In 27 patients with CVI, (Hach stage III), normal arrangement of collagen within the fascia was completely lost. There was a tight, disordered network of fibrils which were themselves sometimes abnormal in appearance. The authors call these changes "fascial insufficiency" and postulate that the ultrastructural basis of fascial insufficiency may be the cause of chronic compartment syndrome which may lead to treatment-resistant crural ulcers.

The authors suggest that these results explain why paratibial fasciotomy may ameliorate leg pain and promote healing of treatment-resistant crural ulcers. Release of pressure in the flexor compartment of the leg by opening the fascial sheath initiates improvement in venous return and facilitates the restoration of normal microcirculation, according to these investigators. They suggest the following relationship: Disorders of the microcirculation due to chronic venous insufficiency damage the fibroblasts which are responsible for the synthesis and metabolism of collagen fibrils. If regulation of the cell is lost, this leads to fascial insufficiency which is responsible for increase in ambulatory pressure within the muscular compartments of the leg.

COMMENTARY

The finding of single smooth muscle cells in the superficial layer of crural fascia is very interesting. The authors suggest that tension in the fascia is not only a passive process but may be actively modified by smooth muscle cells. These investigations are very interesting and show a new pathophysiological point of view of CVI and a new of way of treating resistant crural ulcers. In my opinion, the suggestion that chronic compartment syndrome is responsible for incurable CVI is not proven. On the other hand, these investigations show ultrastructural changes of deep crural fascia. Perhaps in the planning of surgical treatment of CVI, we must consider not only reduction of reflux in the deep venous system but also paratibial fasciotomy.

This article does provide a fresh point of view on pathology and treatment of chronic venous insufficiency. ivdfmac2






INFLUENCE OF A SPECIALIZED LEG ULCER SERVICE AND VENOUS SURGERY ON THE OUTCOME OF VENOUS LEG ULCERS
Ghauri ASK, Nyamekye I, Grabs AJ, Farndon JR, Whyman MR, Poskitt KR
Eur J Vasc Endovasc Surg 1998; 16:238-44


ABSTRACT AND COMMENTARY BY:
Prof. dr. hab. med. Zygmunt Mackiewicz
Bydgoszcz, Poland


This study assesses the influence of noninvasive vascular assessment and superficial venous surgery on the outcome of chronic leg ulcers within a community service. All patients who were being treated for leg ulcers in the community by district or practice nurses during a three-month period were identified from prospectively completed computerized patient database and general practitioner file records. A sample of 200 patients was selected. Exclusion criteria included duration of leg ulceration less than four weeks, arterial or malignant etiology, and ulcers outside the gaiter region. Five community-based leg ulcer clinics were established to which patients were referred. Each limb was initially assessed for arterial disease using hand-held Doppler to measure ankle brachial index. Venous dysfunction was assessed using color venous duplex ultrasonography. Venous patency and reflux were assessed in the common femoral, superficial femoral, popliteal, saphenofemoral junction, greater and lesser saphenous, and perforator segments.

Patients were seen weekly in community clinics and four-layer, graduated-compression bandaging was applied. Patients with superficial venous incompetence in the absence of deep venous incompetence on duplex imaging were offered corrective superficial venous surgery to the affected limb. Ulcers with horizontal length more than 3 cm were pinch grafted in the community clinics. Healed limbs were treated with grade 2 below-knee compression stockings. Healing rates at 12 and 24 weeks were calculated. All statistical analyses were performed on a PC.

Healing and recurrence rates were compared between the ulcerated limbs (n = 149) in a random sample of 200 patients treated in the community clinics and consecutive limbs (n = 200) from 180 patients treated in specialized clinics.

After the five clinics were established, healing rates increased from 12% to 53% at 12 weeks and from 29% to 68% at 24 weeks (p = 0.01). Recurrence rates decreased from 43% to 21% at six months and from 54% to 23% at 12 months (p = 0.01). Superficial venous surgery reduced recurrence to 9% at one year.

The authors conclude that the outcome of leg ulcers is improved by a vascular-led community service, that compression bandaging should be applied to limbs with an ankle brachial index > 0.85, and that routine surgical correction should be done in cases with reflux limited to the superficial venous system as this may further reduce the chance of recurrence.

COMMENTARY

In my opinion, these investigations confirm that suitable bandaging of legs with chronic venous insufficiency reduces the probability of ulceration. Compression therapy performed by well-educated physicians or nurses can reduce ulcer recurrence rate during 12 and 24 months of followup. It is very important that a correct diagnosis be made by Doppler and duplex examinations. One can assess the arterial flow in the limb (ABI) and the other can also assess the gradation of reflux in the deep and superficial venous systems.

The results suggest that improvement in leg ulcer outcome may be achieved by appropriate treatment in specialized vascular-led community clinics. While this kind of treatment is not possible in every country, I believe that stressing the importance of compression therapy in improving ulcer healing to medical students and nurses is the best alternative.

The important conclusion of this investigation is the role of surgery to reduce recurrence of healed ulcers to 9% after one year.

I agree with the authors that color venous duplex provides the most accurate noninvasive method of patient selection and that surgical correction of superficial venous diseases is most important to decrease recurrence.



It is known that even after well-done compression therapy and surgery to the superficial veins, there will still be a number of patients with nonhealed leg ulcers. In my opinion, there are not a great number of patients with indications for special hemodynamic examinations such as venous refilling time by plethysmography, venous reflux index by air plethysmography, or descending phlebography using Kistner's classification in the deep venous system. These will lead to a meticulous selection of patients for venous reconstructive surgery, especially for venous valve reconstruction which can also reduce the number of non-healed leg ulcers. In my experience, however, that kind of treatment is applied in a very selective group of patients.






MINI ABSTRACTS
John J. Bergan, M.D.
Items of Interest Which Have Crossed the Editor's Desk
(Provided for reference purposes and general interest)



The Limerick Leg Ulcer Project: Early Results
Castineira F, Fisher H, Coleman D et al.
Ir J Med Sc 1999; 168:17-20

More data on leg ulcers.



Risk of and Prophylaxis for Venous Thromboembolism in Hospital Patients
THRiFT II Consensus Group
Phlebology 1998; 13:87-97

This is the second THRiFT consensus group report. It concludes that there is overwhelming evidence that thromboembolic prophylaxis reduces the incidence of postoperative deep venous thrombosis and pulmonary embolism. Recommendations are made with regard to stratification of risk and the setting up of guidelines within specific hospitals.



Economic Analysis of Low-Dose Heparin Versus the Low-Molecular-Weight Heparin Enoxaparin for Prevention of Venous Thromboembolism after Colorectal Surgery
Etchells E, McLeod RS, Geerts W et al.
Arch Intern Med 1999; 159:1221-28

This article concludes that heparin and enoxaparin are equally effective in preventing venous thromboembolic episodes but low-dose heparin, not low-molecular-weight heparin, is a more economically attractive choice.



Infusion Phlebitis in Patients with Acute Pneumonia: A Prospective Study
Monreal M, Quilez F, Rey-Joly C et al.
Chest 1999; 115:1576-80

It is agreed that short intravenous lines have to be removed more often because of phlebitis than longer lines. This study is one of few which analyzes various factors which enter into the production of phlebitis, and the authors' conclusion is that long lines should be used if the infusion is to be of greater than 36 hours' duration.