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Biomedical subjects

S S Ramasastry

Publications and source records attributed to S S Ramasastry.

At least 19 recordsLinked to original sources
PubMed1997

Hyperbaric oxygen therapy and free radical production: an experimental study in doxorubicin (Adriamycin) extravasation injuries.

The role of hyperbaric oxygen (HBO) therapy in free radical-mediated tissue injury is not clear. HBO has been shown to enhance the antioxidative defense mechanisms in some animal studies, but HBO has also been reported to increase the production of oxygen free radicals. To investigate this controversy, we studied the effect of HBO in a doxorubicin (Adriamycin) extravasation model, because the cytotoxic activity of doxorubicin is partly related to its quinone structure, which leads to the formation of cytotoxic oxygen intermediates. Fifty-four Sprague-Dawley rats underwent injection of 0.3 ml doxorubicin solution (2 mg per milliliter) intradermally on both flanks as described by Rudolph and colleagues. Group I (N = 28) received HBO treatment (2 hours at 2 ATA) for 3 days prior to injection and 7 days postinjection. Group II (N = 26) received no HBO treatment. At 2, 3, and 5 weeks, the size of the ulcers and the surrounding area of alopecia in group I (+HBO) were significantly larger than in group II (-HBO): 112.2 mm2 vs. 42.8 mm2 (p < 0.01) and 1,132.2 mm2 vs. 364.8 mm2 (p < 0.005). Biochemical analysis of the biopsied skin ulcers, to measure the parameters of oxygen free radical production, indicated (similar) low levels of xanthine oxidase for both groups. However, significantly elevated levels of malonyldialdehyde (MDA), indirect evidence of free radical production, was observed in group I (+HBO) in comparison with group II (-HBO): 36.58 vs. 5.84 ng per minute per milligram protein (p < 0.001), which might indicate free radical-induced cellular injury. It is concluded that in this animal study the cytotoxicity of doxorubicin is potentiated by HBO therapy. The elevated levels of MDA suggest a direct additive cytotoxic effect by increased membrane lipid peroxidation. HBO therapy, therefore, might be deleterious in the early (preulcer) stage of doxorubicin extravasation.

Animals↗
PubMed1997

Free latissimus dorsi muscle transfer using an endoscopic technique.

Endoscopic techniques in plastic surgery have involved aesthetic procedures such as facelift, breast augmentation, abdominoplasty, and placement of tissue expanders. Recently, endoscopic harvest of the donor tissue for free flap transfer has included the omentum, jejunum, latissimus dorsi muscle, and rectus abdominis muscle. Ten patients with a soft-tissue defect in the lower extremity were successfully reconstructed from December 1994 to October 1995 with a free muscle transfer after endoscopic harvest of the latissimus dorsi muscle. Nine patients were male and 1 patient was female. A 5- to 6-cm incision was initially made along the posterior axillary line, allowing direct identification of the thoracodorsal vascular pedicle. The latissimus dorsi muscle was dissected posteriorly until the limits of open dissection were reached, and then the dissection was continued under endoscopic visualization. The largest harvested muscle was 15 x 25 cm in size. Follow-up ranged from 6 to 15 months. We believe that plastic surgeons can take advantage of endoscopic techniques to obtain reliable and safe results, with smaller scars and reduced postoperative donor site morbidity such as pain and wound-healing problems. This technique may prove particularly applicable to women, children, and patients who are prone to hypertrophic scars.

Adolescent↗
PubMed1996

Reconstruction of complex chest wall defects.

BACKGROUND: Reconstruction of complex chest wall defects represents a major challenge and requires close cooperation between the cardiothoracic and reconstructive surgeon to achieve an optimal outcome and reduce the incidence of complications. The principles of chest wall reconstruction include control of infection, local wound care, wide debridement of all necrotic and devitalized tissues, obliteration of all residual cavities and spaces with well-vascularized tissues, reestablishment, when necessary, of the continuity and skeletal stability of the chest wall, and immediate or early definitive coverage of all defects with well-vascularized tissues. METHODS: This paper is based on our experience with 113 patients who underwent chest wall reconstruction for a variety of defects resulting from infection, trauma, tumor extirpation, and radionecrosis. All patients were treated with a variety of muscle flaps and/or omentum which provided obliteration of dead space and coverage. Seven patients with large anterolateral defects required additional skeletal stability with synthetic patches or mesh. RESULTS: 88.6% of patients healed without significant problems. 8.8% had major complications requiring reoperation and prolonged hospitalization while 4.4% had minor complications. CONCLUSIONS: Based on long-term experience, we believe that currently the use of well-vascularized tissue is the method of choice for reconstruction of complex chest wall defects. This provides stable coverage, reduces hospital stay, and thus lowers overall care cost for these patients.

Debridement↗
PubMed1996

Postoperative abdominal wall defects with enterocutaneous fistulae.

BACKGROUND: Abdominal wall dehiscence with an associated enterocutaneous fistula is a surgical complication with high morbidity and mortality. Management of the abdominal wall defect is complicated by the continued emergence of liquid bowel contents. PATIENTS AND METHODS: Large abdominal wall wounds of 10 patients with postoperative abdominal wall dehiscence and active enterocutaneous fistulae were managed with early skin grafting directly onto the granulated abdominal viscera. RESULTS: Skin graft take averaged 93 +/- 12%, and there were no perioperative complications related to the skin grafting procedure. Overall mortality was 1 out of 10 patients. Enterocutaneous fistula output did not prove overly injurious to the skin grafts. Wound care was simplified in all but 1 patient with fitting of an ostomy appliance. CONCLUSION: Temporary abdominal wall wound closure with skin grafts improved patient comfort and simplified wound care in a staged reconstructive approach to this surgical complication.

Abdominal Injuries↗
PubMed1996

Paraffin plombage of the chest revisited.

Complications related to previous thoracic plombage procedures are not uncommon. The management of these complication can be challenging. We present a patient who had a partial resection of the left upper lobe, a seven-rib thoracoplasty, and paraffin wax plombage 38 years previously, in whom a chest wall mass and a discharging sinus developed. She underwent excision and debridement of the paraffin wax mass followed by serratus anterior and latissimus dorsi pedicled muscle intrathoracic transposition. Follow-up at 2 years revealed excellent cosmetic and functional results.

Aged↗
PubMed1995

Soft tissue closure and plastic surgical aspects of large open myelomeningoceles.

The majority of open myelomeningocele defects are small enough that following the neural repair, soft tissue closure is achieved by simple undermining of the skin edges and tension-free approximation in the midline. The larger defects, greater than 5 cm diameter, cannot be closed reliably by simple skin undermining. Such larger defects call for a close cooperation between the neurosurgeon and the plastic surgeon. In the authors' experience, a reliable, safe method of reconstruction of thoracolumbar and lumbosacral meningomyelocele defects involves the en bloc medial advancement of latissimus dorsi and gluteus maximus musculocutaneous units and reapproximation in the midline. This is the authors' preferred method for all medium and large size defects greater than 5 cm in diameter. This method permits primary closure of the defect in three layers. The flaps are based on the thoracodorsal and superior gluteal vessels and the intervening thoracolumbar fascia. This method provides a tension-free, durable, and viable soft tissue coverage over the dural repair. The flaps do not alter the nerve supply of the muscles involved and merely redefine the muscle origins, without compromising muscle function.

Follow-Up Studies↗
PubMed1995

Reconstruction of posterior trunk defects.

A high rate of success can be expected in the management of posterior trunk defects with muscle flaps. The surgeon has to adhere closely to the basic reconstructive principles of adequate debridement of all necrotic or devitalized tissues; management of infection with local wound care and appropriate antibiotic therapy; and coverage with well-vascularized tissue to obliterate any residual dead space and to cover bone grafts, orthopedic hardware, and vital structures such as the dura and spinal cord. Flap selection is also of paramount importance for success, and only muscles with appropriate arc of rotation, vascularity (vascular pedicles outside the field of radiation injury, or intact vascularity following previous procedures) and bulk should be used. Adequate flap mobilization to obtain a tension-free closure and judicious use of drains and perioperative antibiotic agents are essential. Occasionally, microvascular free-tissue transfer may be necessary if local flaps are unavailable. The complications of flap reconstruction include partial flap loss, persistent dead space for lack of adequate muscle bulk, and persistent infection. Debridement and re-advancement of the flap is adequate in most cases. If there is significant or total flap loss, however, a second flap reconstruction is often necessary to obliterate the dead space and protect vital structures.

Back↗
PubMed1994

Pyruvate inhibits growth of mammary adenocarcinoma 13762 in rats.

The growth of implanted mammary adenocarcinoma 13762 was measured in rats consuming a liquid diet (35% fat, 18% protein, 47% carbohydrate) supplemented with pyruvate (37.3 g/liter; n = 13) or maltose-dextrin (placebo; n = 13) for 21 days. Mean tumor diameter, measured on day 11, 14, 18, and 21 subsequent to tumor implantation, was 41, 32, 21, and 19% smaller in the pyruvate group (P < 0.05). When euthanized, tumor weight was also smaller in the pyruvate group: pyruvate = 15.0 +/- 2.3 (SEM) g; placebo = 24.9 +/- 3.2 g, P < 0.05. Visual inspection of organs suggested decreased lung metastases with pyruvate feeding (P < 0.05). Upon microscopic evaluation of organs, hepatic tumor was found only in the placebo group. We conclude that pyruvate inhibits implanted tumor growth in rats.

Adenocarcinoma↗
PubMed1993

Liposuction-assisted revision and recontouring of free microvascular tissue transfers.

Liposuction has become a widely accepted and utilized technique that allows the aesthetic surgeon to improve regional definition and contour. Although the techniques of liposuction have now been extended to a variety of noncosmetic procedures as well, the application of this technique in the area of reconstructive surgery has lagged. To ascertain the applicability and effectiveness of liposuction for the revision of free microvascular tissue transfers we undertook a retrospective analysis of our free flap reconstruction cases that were revised and recontoured using liposuction. From this review of 12 cases we found liposuction to be a safe and effective technique for the delayed revision of free flap reconstructions of the head and neck region and lower extremity.

Adult↗
PubMed1992

Lower extremity reconstruction using a long-cryopreserved venous allograft for free flap venous outflow.

Vein grafts are used frequently in microvascular surgery, but an adequate supply of autogenous veins is not always available. The search for an ideal substitute for autogenous vein continues. We present a case of lower extremity reconstruction made difficult by lack of suitable autogenous vein for venous outflow from a rectus abdominus free flap. A 36 cm cryopreserved allograft saphenous vein was used on an emergency basis for this problem.

Aged↗
PubMed1992

Microvascular free tissue transfer for reconstruction of head and neck cancer defects.

Over the last 10 years, microvascular free tissue transfer techniques have broadened the range of the head and neck surgeon, allowing for successful reconstruction of extensive curative extirpations in one operation with minimal morbidity. Success rates of more than 90% are now being achieved consistently. This article provides an overview of these revolutionary techniques for oral cavity, mandibular, and hypopharyngeal reconstructions. Patients are selected for microvascular free tissue transfer because of the large size of their defect, its location (eg, anterior mandibular loss), or complexity (circumferential defects of the hypopharynx). Others may be good candidates for this surgery because of previous radiotherapy or failed reconstructive surgery. Donor sites range from the radial forearm to the jejunum.

Follow-Up Studies↗
PubMed1989

Chronic osteomyelitis of the clavicle.

Osteomyelitis of the clavicle is an uncommon disease, but it should be considered in patients who present with pain, cellulitis, or drainage in the sternoclavicular area following head and neck surgery, irradiation, subclavian vein catheterization, or immunosuppression. An idiopathic presentation is possible. In contrast to primary osteomyelitis of the clavicle, which is occasionally seen in children, secondary osteomyelitis is quite rare. It is often mistaken for a fracture or a possible neoplasm on plain x-rays. Tomograms and CT scanning are confirmatory, and in early cases, technetium-99m bone scanning can be helpful. Treatment must include early, aggressive surgical debridement of all affected tissues, followed by wound coverage with a well-vascularized flap and perioperative antibiotics.

Abscess↗
PubMed1989

Treatment of a cluster headache patient in a hyperbaric chamber.

A patient with severe cluster headaches was treated in a hyperbaric chamber on two occasions. Her symptoms had been refractory to other treatment modalities including conventional oxygen therapy. On both occasions her pain was promptly relieved while breathing 100% oxygen at two atmospheres of pressure. This is the first known reported case of a cluster headache treated with hyperbaric oxygen. A prospective study is needed to substantiate the efficacy of this treatment modality for cluster headaches.

Cluster Headache↗
PubMed1989

Surgical management of difficult wounds of the groin.

Coverage of large defects of the soft tissue of the groin present a challenging problem. Exposure of the femoral vessels or prosthetic grafts requires urgent coverage with well vascularized tissue. The medial and lateral femoral circumflex arteries supply the gracilis, sartorius, vastus lateralis, rectus femoris and tensor fascia lata muscles, permitting the use of these muscles or myocutaneous flaps for coverage of groin defects when the femoral artery is intact. With extensive wounds of the groin resulting from trauma, ablation of carcinoma and vascular reconstruction for atherosclerosis involving the femoral vessels, the aforementioned flaps cannot be used. The external iliac artery supplies the rectus abdominis muscle through the deep inferior epigastric artery and the interal oblique muscle through the deep circumflex iliac artery. These muscle flaps are available when the femoral vessels are not intact. If the ipsilateral iliofemoral vessels are not intact, branches of the contralateral iliac artery through deep inferior epigastric artery and deep circumflex iliac artery provide suitable flaps for covering the groin wound. We review our experience with the management of difficult groin wounds (n = 31) and present a systematic approach to reconstruction of the groin based on these anatomic facts.

Female↗
PubMed1988

Macroglossia and ankyloglossia in Beckwith-Wiedemann syndrome.

Since the recognition of the Beckwith-Wiedemann syndrome was first noted in 1963, the number of associated anomalies has vastly increased. The rate of appearance of this abnormality is 1 in 13,5000 births. This article presents a case that includes macroglossia and ankyloglossia along with a bifid uvula and a submucous cleft of the palate. A discussion of treatment follows.

Ankylosis↗
PubMed1988

Surgical management of severe mammary hidradenitis suppurativa.

Hidradenitis suppurativa is a devastating disease of the apocrine sweat glands. The chronic form is characterized by a malodorous discharge from multiple draining sinuses embedded in dense fibrous tissue, and physical discomfort. The disease commonly affects the axillary, perineal, and perianal regions. A case of hidradenitis suppurativa of the mammary gland necessitating mastectomy is presented here to illustrate the severity of the disease at an uncommon site. As in other regions of the body, aggressive surgical intervention provides a chance for rapid recovery. The surgical treatment should be tailored to the severity of the disease.

Female↗
PubMed1988

The critical relationship between free radicals and degrees of ischemia: evidence for tissue intolerance of marginal perfusion.

UNLABELLED: Skin-flap ischemia has been associated with the presence of free radicals. In this study, two enzyme systems involved in free-radical metabolism were used to compare a distal skin flap to a skin graft. Forty-two rats were divided into several test groups. A 10 X 3 cm dorsal rat flap was used, and tissue biopsies for xanthine oxidase and malonyldialdehyde (MDA) were obtained 2.5, 5.5, and 8.5 cm from the base of the flap at the hours given. In group I (control), the flap was outlined but not elevated, and biopsies were obtained. In group II, the flap was elevated, and biopsies were obtained at 6 hours. In group III, the flap was elevated, the distal 4 X 3 cm was amputated and replaced as a full-thickness skin graft, and biopsies were obtained at 6 hours. In group IV, the flap was elevated, and biopsies were obtained at 12 hours. In group V, the flap was treated as in group III, and biopsies were obtained at 12 hours. In group VI, the flap was elevated, and biopsies were obtained at 24 hours. In group VII, the flap was treated as in group III, and biopsies were obtained at 24 hours. RESULTS: Xanthine oxidase was significantly higher in all distal biopsies compared to proximal biopsies. Xanthine oxidase also increased with time. Malonyldialdehyde increased over time as well as with distance from the flap base. Distal flap biopsies at 24 hours had greatly increased levels of malonyldialdehyde compared to skin grafts (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗