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Biomedical subjects

M Koshy

Publications and source records attributed to M Koshy.

At least 37 records · Page 2Linked to original sources
PubMed1995

Surgery and anesthesia in sickle cell disease. Cooperative Study of Sickle Cell Diseases.

From 1978 to 1988, The Cooperative Study of Sickle Cell Disease observed 3,765 patients with a mean follow-up of 5.3 +/- 2.0 years. One thousand seventy-nine surgical procedures were conducted on 717 patients (77% sickle cell anemia [SS], 14% sickle hemoglobin C disease [SC], 5.7% S beta zero thalassemia, 3% S beta zero + thalassemia). Sixty-nine percent had a single procedure, 21% had two procedures, and the remaining 11% had more than two procedures during the study follow-up. The most frequent procedure was abdominal surgery for cholecystectomy or splenectomy (24% of all surgical procedures, N = 258). Of these, 93% received blood transfusion, and there was no association between preoperative hemoglobin A level and complication rates (except reduction in pain crisis). Overall mortality within 30 days of a surgical procedure was 1.1% (12 deaths after 1,079 surgical procedures). Three deaths were considered to be related to the surgical procedure and/or anesthesia (0.3%). No deaths were reported in patients younger than 14 years of age. Sickle cell diseases (SCD)-related complications after surgery were more frequent in SS patients who received regional compared with general anesthesia (adjusted for risk level of the surgical procedure, patient age, and preoperative transfusion status, P = .058). Non-SCD-related postoperative complications were higher in both SS and SC patients who received regional compared with those who received general anesthesia (P =.095). Perioperative transfusion was associated with a lower rate of SCD-related postoperative complications for SS patients undergoing low-risk procedures (P = .006, adjusted for age and type of anesthesia), with crude rated of 12.9% without transfusion compared with 4.8% with transfusion. In SC patients, preoperative transfusion was beneficial for all surgical risk levels (P = .009). Thus, surgical procedures can be performed safely in patients with SCD.

Adolescent↗
PubMed1995

A comparison of conservative and aggressive transfusion regimens in the perioperative management of sickle cell disease. The Preoperative Transfusion in Sickle Cell Disease Study Group.

BACKGROUND: Preoperative transfusions are frequently given to prevent perioperative morbidity in patients with sickle cell anemia. There is no consensus, however, on the best regimen of transfusions for this purpose. METHODS: We conducted a multicenter study to compare the rates of perioperative complications among patients randomly assigned to receive either an aggressive transfusion regimen designed to decrease the hemoglobin S level to less than 30 percent (group 1) or a conservative regimen designed to increase the hemoglobin level to 10 g per deciliter (group 2). RESULTS: Patients undergoing a total of 604 operations were randomly assigned to group 1 or group 2. The severity of the disease, compliance with the protocol, and the types of operations were similar in the two groups. The preoperative hemoglobin level was 11 g per deciliter in group 1 and 10.6 g per deciliter in group 2. The preoperative value for hemoglobin S was 31 percent in group 1 and 59 percent in group 2. The most frequent operations were cholecystectomies (232), head and neck surgery (156), and orthopedic surgery (72). With the exception of transfusion-related complications, which occurred in 14 percent of the operations in group 1 and in 7 percent of those in group 2, the frequency of serious complications was similar in the two groups (31 percent in group 1 and 35 percent in group 2). The acute chest syndrome developed in 10 percent of both groups and resulted in two deaths in group 1. A history of pulmonary disease and a higher risk associated with surgery were significant predictors of the acute chest syndrome. CONCLUSIONS: A conservative transfusion regimen was as effective as an aggressive regimen in preventing perioperative complications in patients with sickle cell anemia, and the conservative approach resulted in only half as many transfusion-associated complications.

Adolescent↗
PubMed1995

Sickle cell disease and pregnancy.

Sickle cell disease refers to a group of genetic disorders characterised by the predominance of hemoglobin S. This includes sickle cell anemia (SS) sickle hemoglobin C disease (SC), sickle beta thalassemia plus (S beta + Thal), sickle beta thalassemia zero (beta zero Thal), sickle with alpha thalassemia (SS alpha Thal) and rare combinations of sickle hemoglobin with Hb D, Hb O, etc. While pregnancy does carry risk for the woman with sickle cell disease (SCD) and for the fetus, pregnancy can be well tolerated by the major genotypes. Infants born from these pregnancies may tend to be small for gestational age and undergo premature delivery. While complications for both sickle-related events and for pregnancy are seen, data to date state that women are able to complete their pregnancies successfully. Counselling, regular prenatal visits and aggressive treatment of acute events are always indicated. There is no proof that prophylactic transfusion alters the outcome of pregnancy. Transfusion therapy should be reserved for those patients with previous perinatal mortality, pre-eclampsia, acute chest syndrome, new onset neurological event, severe anemia and in preparation for surgical intervention. Thus, blood transfusion will continue to have a role in management of obstetrical and medical indications accompanied by meticulous prenatal care and early detection of complications. In addition, newborn screening should be recommended for the early detection of infants with disease.

Anemia, Sickle Cell↗
PubMed1995

Health insurance status and the use of emergency and other outpatient services by adults with sickle cell disease.

STUDY OBJECTIVE: To evaluate insurance status and frequency of use of emergency services in adults with sickle cell disease. DESIGN: Retrospective analysis of visits. SETTING: Emergency department and outpatient clinics of an urban university hospital. PARTICIPANTS: One hundred seventy-two subjects, who made 771 visits to the ED during 1990. RESULTS: Of the 172 subjects, 31 were covered by commercial insurance, 32 were covered by Medicare, and 109 were covered by Medicaid or were uninsured. Insurance status and frequency of use of emergency services were independent (P > .05). On discriminant analysis, Medicaid-covered and uninsured subjects were correctly classified, but commercially insured and Medicare subjects were not. Medicaid and uninsured subjects were more likely to be younger and to live closer to the hospital (P < .00005). High-frequency users of emergency services were discriminated from low-frequency users. High-frequency users were more likely to be younger, to be users of primary-care services, and to live closer to the hospital (P = .0004). CONCLUSION: Provision of primary-care services or stable insurance in the form of commercial insurance or Medicare did not decrease use of emergency services in subjects with sickle cell disease in a group of patients selected from one urban academic ED.

Adult↗
PubMed1995

Lower limb salvage by microvascular free-tissue transfer in patients with homozygous sickle cell disease.

Chronic, excruciatingly painful ulcerations of the lower extremities in patients with homozygous sickle cell anemia (HbSS) present a frustrating clinical problem for the reconstructive surgeon. Despite adequate wound care and skin grafting, there is a dismally high incidence of recurrence. Furthermore, there is a paucity of reliable locoregional fasciocutaneous, muscle, and myocutaneous flaps in the ankle region. Free-tissue transfer has become the procedure of choice for reconstruction of the lower third of the leg. However, in sickle cell anemia, does the obligate period of flap ischemia inherent in free-tissue transfer inevitably doom a flap to failure? We present our multidisciplinary experience over 55 months with five free flaps in four homozygous sickle cell anemia patients 21 to 38 years old who had chronic nonhealing leg ulcerations. Special perioperative measures included exchange transfusion to lower hemoglobin S to below 30 percent, maintaining the hematocrit at 31 to 35 percent, intraoperative flap washout and perfusion with warm heparinized saline-dextran solution, administration of dextran and aspirin intraoperatively and postoperatively, prophylactic topical and systemic anti-Pseudomonas antibiotics, supplemental oxygen, and warm ambient room temperature. Flaps included the latissimus dorsi muscle (two patients), the temporoparietal fascia (one patient), and "split" omentum for bilateral lower limb salvage (one patient). Successful free-tissue transfer was accomplished in all patients. One patient suffered gradual partial occlusion of the microcirculation by sickled erythrocytes following a transient hypothermic, hypotensive episode. Sufficient flap tissue survived to permit skin grafting with an excellent result. Pseudomonas infection occurred in two patients (three flaps).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Accelerated healing of chronic sickle-cell leg ulcers treated with RGD peptide matrix. RGD Study Group.

Leg ulcers are a chronic manifestation of sickle-cell disease (SCD) and are often painful, disabling, and difficult to treat. RGD peptide matrix treatment is a novel therapy designed to provide a topical synthetic extracellular matrix that can act as a temporary substitute for the damaged natural matrix at the ulcer site. In this randomized, placebo-controlled, double-blind, prospective, multicenter investigation, SCD patients with full-thickness leg ulcers were treated with standard therapy plus RGD peptide matrix or saline placebo once weekly for up to 10 weeks. Healing in patients with chronic ulcers (2 months or greater in duration) was significantly accelerated (P = .0085) in RGD peptide matrix recipients compared with the placebo group. In these chronic ulcer cases, the average percent ulcer closure (decrease in ulcer surface area) in the RGD peptide matrix group (54.4% +/- 8.9%) exceeded that in the placebo group (19.0% +/- 24.3%) nearly threefold by study endpoint. Furthermore, RGD peptide matrix was equally effective in promoting healing of long persistent ulcers and ulcers of shorter duration. In contrast, standard therapy plus placebo was significantly less effective (P = .001) in promoting healing for ulcers of progressively greater duration. The results of this study provide preliminary evidence that RGD peptide matrix treatment may significantly accelerate healing of chronic sickle-cell leg ulcers.

Adolescent↗
PubMed1993

A simple, practical model for reducing alloimmunization in patients with sickle cell disease.

Patients with sickle cell disease (SCD) form immune alloantibodies more frequently than other transfused populations because red cells (RBCs) from white donors (with a higher incidence of certain Rh, Duffy, Kell, and Kidd blood group antigens) are transfused to black patients often lacking these antigens. We propose a model to reduce alloimmunization in patients with SCD by providing them with blood from only black random donors. Rationale is shown by examining calculations based on the phenotype E-, C-, Fy(a-), K-, and Jk(b-). There is a 7% probability that this phenotype belongs to a white donor, while there is a 93% probability that this phenotype belongs to a black donor. The probability of selecting blood from a black donor identical with the above phenotype for black recipients from an all black population and from a typical urban blood inventory population (90% white, 10% black) is 1/4 and 1/33, respectively. Therefore, an 8-fold greater chance of selecting antigen non-identical blood occurs if blood is obtained from a typical urban donor population as compared to a black population. Based on these calculations, alloimmunization can be reduced prospectively in patients with SCD by meeting their transfusion requirements with blood selected from random black blood donors.

Antibody Formation↗
PubMed1993

Osteonecrosis of the humeral head in sickle cell disease.

The prevalence and incidence of osteonecrosis (ON) of the humeral head in sickle cell disease was determined by a study of 2524 patients who were entered into a prospective study and followed for an average of 5.6 years. At entry, 5.6% had roentgenographic evidence of ON in one or both shoulders. There was little difference in age-adjusted prevalence among genotypes, but there were striking differences in age-specific rates. Observed at ages ranging from five to 24 years, 3.25% of sickle cell anemia (S/S) patients, but only 1.1% of sickle cell disease (S/C) patients, had ON. No S/beta+ thalassemia patients younger than 25 years of age had ON on entry. The highest age-adjusted incidence rate was found in S/S patients with concomitant alpha-thalassemia (4.85 per hundred patient-years), followed by S/beta zero-thalassemia (4.84 per hundred patient-years), S/beta+ thalassemia (2.61 per hundred patient-years), S/S without alpha-thalassemia (2.54 per hundred patient-years), and S/C (1.66 per hundred patient-years). Only 20.9% of patients reported pain or had limited range of movement at the time of diagnosis. Sickle cell disease is a frequent cause of ON of the humeral head, especially in children and young adults.

Adolescent↗
PubMed1992

Hydroxyurea: effects on hemoglobin F production in patients with sickle cell anemia.

Patients with sickle cell anemia were treated with daily doses of hydroxyurea, to assess pharmacokinetics, toxicity, and increase in fetal hemoglobin (Hb) production in response to the drug. Plasma hydroxyurea clearances were not a useful guide to maximum tolerated doses of the drug. The mean daily single oral dose that could be maintained for at least 16 weeks was 21 mg/kg (range, 10 to 35 mg/kg). Among 32 patients, last HbF levels were 1.9% to 26.3% (mean, 14.9%) with increases in HbF over initial values of 1.4% to 20.2% (mean, 11.2%). The most significant predictors of last HbF were last plasma hydroxyurea level, initial white blood count and initial HbF concentration. Last HbF was not related to beta globin haplotype or alpha globin gene number. No serious toxicity was encountered. Clinically significant bone marrow depression was avoided, and chromosome abnormalities after 2 years of treatment were no greater than those observed before treatment. The period of observation has been too short to evaluate the risk of carcinogenesis. Patient's red cells developed striking macrocytosis. Median red cell Hb concentrations did not change. Hb concentrations increased, on average 1.2 g/dL, but serum erythropoietin levels increased. Patients' body weights increased, and some returned to work or school, but no conclusions regarding therapeutic efficacy could be drawn from this uncontrolled open-label study.

Adult↗
PubMed1992

Pancytopenia caused by unsuspected pernicious anemia complicating sickle cell beta-thalassemia.

We have described a a 23-year-old black woman with sickle cell beta-thalassemia who had a urinary tract infection and who was incidentally found to be pancytopenic. Although her anemia was categorized as "normocytic, normochromic" by an electronic particle counter, evaluation of the pancytopenia confirmed unsuspected pernicious anemia. Greater vigilance and a higher index of suspicion are crucial for early diagnosis of pernicious anemia in patients with other known hemoglobinopathies.

Adult↗
PubMed1991

Sickle cell disease as a cause of osteonecrosis of the femoral head.

BACKGROUND AND METHODS: Osteonecrosis of the femoral head is an important complication of sickle cell disease. We studied 2590 patients who were over 5 years of age at entry and followed them for an average of 5.6 years. Patients were examined twice a year, and radiographs of the hips were taken at least twice: at study entry and approximately three years later. RESULTS: At study entry, 9.8 percent of patients were found to have osteonecrosis of one or both femoral heads. On follow-up, patients with the hemoglobin SS genotype and alpha-thalassemia were at the greatest risk for osteonecrosis (age-adjusted incidence rate, 4.5 cases per 100 patient-years, as compared with 2.4 in patients with the hemoglobin SS genotype without alpha-thalassemia and 1.9 in those with the hemoglobin SC genotype). Although the rate of osteonecrosis in patients with the hemoglobin SC genotype did not differ significantly from that in patients with the hemoglobin SS genotype without alpha-thalassemia, osteonecrosis tended to develop in these patients later in life. Intermediate rates of osteonecrosis were observed among patients with the hemoglobin S-beta zero-thalassemia and the hemoglobin S-beta(+)-thalassemia genotypes (3.6 and 3.3 cases per 100 patient-years, respectively). Osteonecrosis was found in patients as young as five years old (1.8 cases per 100 patient-years for all genotypes). The frequency of painful crises and the hematocrit were positively associated with osteonecrosis. The mean corpuscular volume and serum aspartate aminotransferase level were negatively associated. Twenty-seven patients had hip arthroplasty during the study; 10 were under 25 years of age. Five of the 27 required reoperation 11 to 53 months after the initial operation. CONCLUSIONS: Osteonecrosis of the femoral head is common in patients with sickle cell disease, with an incidence ranging from about 2 to 4.5 cases per 100 patient-years. Patients with the hemoglobin SS genotype and alpha-thalassemia and those with frequent painful crises are at highest risk. The overall prevalence is about 10 percent. The results of hip arthroplasty are poor.

Adolescent↗
PubMed1991

Management of sickle cell anemia and pregnancy.

There has been significant decrease in maternal morbidity and mortality of sickle cell disease patients during pregnancy due to better understanding of the pathophysiology of the disease and physiologic changes during pregnancy. Prophylactic blood transfusion does not appear to reduce complications in patients with sickle cell anemia. Patients with sickle hemoglobin C disease and with S beta thalassemia+ have fewer complications but still need close monitoring. Blood transfusion therapy should be made available for medical and obstetrical complications to include increasing hypoxemia, progressive anemia, acute chest syndrome, twin pregnancy, splenic sequestration syndrome, preeclampsia, septicemia, or prior to general anesthesia and surgery. Blood transfusion therapy is associated with hepatitis, allergic reaction, alloimmunization, AIDS, and iron overload states. These aspects should be considered prior to using blood transfusion therapy. Excellent prenatal monitoring and aggressive intervention should be instituted when problems arise for the successful management of the pregnant patient with sickle cell disease. Prenatal diagnosis and cord blood screening should be made available for the infant. Appropriate pediatric referral and prophylactic penicillin is recommended for the infant with sickle cell disease.

Adult↗
PubMed1991

Quantitative and qualitative platelet abnormalities during pregnancy.

In a 1-year period, 15 of 4048 pregnant women were found to have thrombocytopenia during their first prenatal visit. Their qualitative and quantitative platelet abnormalities were followed up prospectively for 1 to 6 months post partum. Platelet counts returned to normal in 14 of 15 patients 4 to 6 weeks post partum. von Willebrand factor antigen and ristocetin cofactor activity were low in three of 15 patients 4 to 6 weeks post partum, but had been normal during the antepartum period. Two of these three patients had prolonged bleeding times ante partum and post partum. All three patients subsequently were found to have mild type I von Willebrand disease. Six patients had detectable platelet antibodies. Neonatal thrombocytopenia was found in one term infant of a patient with mild thrombocytopenia and negative platelet antibodies. This study suggests that mild, transient, isolated thrombocytopenia can occur in an otherwise normal pregnancy and its incidence may be lower than previously reported. Extensive testing is not indicated unless there is an associated prolonged bleeding time. The possibility of von Willebrand disease or a qualitative platelet disorder should be considered.

Adolescent↗
PubMed1991

Priapism associated with the sickle cell hemoglobinopathies: prevalence, natural history and sequelae.

To determine the prevalence and characteristics of priapism associated with sickle cell hemoglobinopathic conditions we interviewed and examined 52 men with sickle cell anemia, 10 with sickle C disease, 3 with sickle B(+)-thalassemia and 19 with sickle cell trait. Of the men 20 with sickle cell anemia (38%) and 1 with sickle B(+)-thalassemia (33%) reported past priapism attacks. Average patient age at onset in the sickle cell anemia patients was 19 years (range 8 to 30 years). Four men had had only 1 attack. The average number of attacks per year in the remaining patients ranged from 1 to 52. Of the patients who reported multiple attacks the average duration of a typical episode and the duration of the longest self-limiting episode was 1.6 and 7.0 hours, respectively. Six patients had experienced 1 attack that persisted for longer than 24 hours. There were no significant differences between the clinical and hematological parameters of the sickle cell anemia patients who did and did not experience priapism or of the priapism patients who had and had not experienced episodes lasting greater than 24 hours. Six patients had been hospitalized for priapism and 4 were treated with a shunting procedure. Of the latter patients 2 were impotent but there was no significant alteration in the sexual function of the other study participants.

Adolescent↗
PubMed1991

Subarachnoid hemorrhage in sickle-cell disease.

The neurological complications of sickle-cell disease include cerebral intracerebral hemorrhage; subarachnoid hemorrhage (SAH) has been infrequently reported. Among 325 patients with sickle-cell disease followed at the University of Illinois between 1975 and 1989, 11 cases of SAH were identified. Aneurysms were found in 10 of these patients, three of whom had multiple aneurysms. All of the patients had some degree of anemia and nine underwent craniotomy without hematological or neurological complications. From this review it appears that SAH is not uncommon in sickle-cell disease patients and tends to occur at a younger age and with smaller aneurysm size than in the general population. With proper perioperative management, including exchange transfusions to reduce the proportion of hemoglobin S to less than 30%, these patients can undergo angiography and craniotomy without an increased incidence of complications. The techniques used in managing sickle-cell disease patients with SAH are discussed.

Adolescent↗
PubMed1991

Management of pregnancy in sickle cell syndromes.

We have seen a marked decrease in maternal and perinatal morbidity and mortality among pregnant patients with sickle cell disease. This has been the result of coordinated efforts with the obstetric and hematologic teams. Patients are counseled prior to pregnancy regarding the risks and are given the opportunity to modify their life style to prepare for the additional metabolic burden of gestation. Once pregnant, they are instructed in the techniques to recognize and avoid complications. They are observed frequently for the appearance of pain crisis and other medical and obstetric complications. If complications are identified, they should be treated aggressively. Transfusion therapy is important in the management of patients; however, prophylactic transfusion does not change outcome. Although significant laboratory techniques aid in fetal and maternal supervision, the universal fundamentals of good clinical perinatal care provided through the combined efforts of the obstetrician and hematologist contribute to the framework for the modern management and successful outcome of patients with sickle cell disease during pregnancy.

Anemia, Sickle Cell↗
PubMed1990

Vascular lesions in the central nervous system in sickle cell disease (neuropathology).

The incidence of serious neurologic complications in sickle cell disease ranges from 6% to 30% in various series. Our experience indicates that the incidence in adults is approximately 15%. The clinical and neuropathologic correlations at autopsy in 20 sickle cell disease patients are discussed in this paper. Some patients had massive infarcts and/or hemorrhages in the cerebral hemispheres as the terminal event. In some, both infarction and hemorrhage occurred simultaneously; others had thrombosis of major branches of the circle of Willis and in the internal carotid artery on one or both sides. Prominent large arterial occlusive disease in the terminal intracranial portions of the internal carotid arteries and proximal segments of their main branches was frequently observed. The pathology of the brain showed diffuse chronic gliotic scars of microinfarcts in the deep white matter and cerebral gray matter, even when no past neurologic history was recorded. We hypothesize that the vague, nonspecific complaints, including chronic alteration of intellectual and emotional function, of some sickle cell disease patients prior to their death, may constitute the clinical counterpart of disseminated microscopic lesions resulting from small-vessel disease. The pathogenesis of vaso-occlusive disease includes altered cerebral blood flow, platelet response to endothelial injury, and sickled erythrocyte adhesion to endothelium.

Adolescent↗