Biomedical subjects

E Germann

Publications and source records attributed to E Germann.

32 records · Page 2Linked to original sources

PubMed1995

Cultured epithelial autograft: five years of clinical experience with twenty-eight patients.

Cultured epithelial autograft (CEA) has been used as an adjunct in burn wound coverage at the Vancouver Hospital and Health Sciences Centre since 1988, and has been available to all patients admitted with significant burn injuries. During the 5-year period from 1988 to 1992 inclusive, 28 patients treated with CEA survived long enough for assessment. The mean age was 35.3 years with a mean total body surface area burn of 52.2% and a mean total full thickness injury of 42.4%. CEA was applied to wounds covering between 2% and 35% body surface area (BSA; mean 10.4%) after excision to fat or fascia. Most wounds had interim homograft coverage. Preservation of homograft dermis was attempted in three patients at the time of removal without effect. The mean CEA "take" was 26.9% of the grafted area. Eight patients had 50% or greater take and were discharged with between 1 and 19% BSA covered with CEA. Thirteen patients had no take on wounds between 2 and 16% BSA. Overall mortality in burn patients treated at the Vancouver Hospital and Health Sciences Centre from 1988 to 1992 was not significantly different from 1983 to 1987 with the populations being similar in terms of total BSA burns, age, inhalation injury, and homograft availability. When compared to a matched control population from the preceding 5 years, when CEA was not available, there was no significant difference in duration of hospital stay or number of autograft harvests. However, approximately one more debridement without autograft harvest per CEA patient occurred. Timing and depth of wound excision, interim coverage, type of dressing, and wound microbiology were not found to influence good versus poor take. The anterior trunk and thighs were the best recipient sites. Subjective differences between CEA and meshed autograft were noted. The results show that after 5 years of use, CEA engraftment continues to be unpredictable and inconsistent, and hence, it should be used as only a biologic dressing and experimental adjunct to conventional burn wound coverage with split thickness autograft.

Adolescent↗

PubMed1995

Autologous blood use in reduction mammaplasty: is it justified?

A study was undertaken to evaluate the current use of autologous blood predonation within 3 weeks of reduction mammaplasty in our institution. A retrospective study of 153 consecutive patients undergoing reduction mammaplasty between April of 1987 and October of 1992 was analyzed. Nine patients were excluded because of inadequate data, leaving 81 patients in the autologous blood predonation study group and 63 patients in the control group. The two groups were similar with regard to age, preintervention hemoglobin levels, technique of reduction mammaplasty, average number of grams excised per side, estimated blood loss, and duration of hospital stay. Those in the study group, despite preoperative iron therapy initiated just prior to the time of autologous blood donation, had significantly lower preoperative hemoglobin levels (p < 0.001). Seventy-two percent of those patients who donated blood preoperatively received all their blood intraoperatively or within 1 day of surgery. Eleven percent received 1 of their 2 units donated, and the remaining 17 percent were not transfused. Despite 83 percent of the study group patients receiving all or some of their predonated blood, their postoperative hemoglobin levels were not significantly different from those of the control group. We concluded that under our current program, autologous blood predonation for reduction mammaplasty is not beneficial to the patient in the immediate perioperative period.

Adult↗

PubMed1992

Efficacy of 131I ablation following thyroidectomy in patients with invasive follicular thyroid cancer.

The role of thyroid ablation following thyroidectomy for invasive follicular cancer remains controversial. The use of iodine 131 (131I) ablation as adjuvant therapy may facilitate follow-up of patients in whom serum thyroglobulin levels and 131I total body scans are used to detect metastatic disease. It is uncertain if 131I ablation improves survival of patients with follicular thyroid cancer. Thus, the purpose of this study was to determine if survival is enhanced following ablation, with particular reference to those patients with minimally invasive cancer. Between the years 1955 to 1988, 142 patients with invasive thyroid follicular cancer were treated at the British Columbia Cancer Agency, of whom 71 had minimal invasion and no extrathyroidal extension of tumor. In this group of patients, 46 underwent hormone suppression only, 17 had ablation, and 8 had neither. The average follow-up was 9 years and extended beyond 15 years in many patients. Data were entered in a mainframe computer, and Kaplan-Meier survival analysis was used, comparing crude survival, disease-specific survival, and disease-free survival. There was no significant difference between groups. In patients with follicular thyroid cancer and capsular invasion only, 131I ablation does not improve survival compared with patients treated with thyroid hormone suppression only.

Adenocarcinoma↗

PubMed1991

Clinical parameters predictive of malignancy of thyroid follicular neoplasms.

Needle aspiration biopsy is commonly employed in the evaluation of thyroid nodules. Unfortunately, the cytologic finding of a "follicular neoplasm" does not distinguish between a thyroid adenoma and a follicular cancer. The purpose of this study was to identify clinical parameters that characterize patients with an increased risk of having a thyroid follicular cancer who preoperatively have a "follicular neoplasm" identified by needle aspiration biopsy. A total of 395 patients initially treated at Vancouver General Hospital and the British Columbia Cancer Agency between the years of 1965 and 1985 were identified and their data were entered into a computer database. Patients with thyroid adenomas were compared to patients with follicular cancer using the chi-square test and Student's t-test. Statistically significant parameters that distinguished patients at risk of having a thyroid cancer (p less than 0.05) included age greater than 50 years, nodule size greater than 3 cm, and a history of neck irradiation. Sex, family history of goiter or neoplasm, alcohol and tobacco use, and use of exogenous estrogen were not significant parameters. Patients can be identified preoperatively to be at an increased risk of having a follicular cancer and accordingly appropriate surgical resection can be planned.

Adenocarcinoma↗

PubMed1991

Comparison of silver sulphadiazine 1 per cent, silver sulphadiazine 1 per cent plus chlorhexidine digluconate 0.2 per cent and mafenide acetate 8.5 per cent for topical antibacterial effect in infected full skin thickness rat burn wounds.

Silver sulphadiazine 1 per cent (SS), silver sulphadiazine 1 per cent plus chlorhexidine digluconate 0.2 per cent (SS + CD 0.2 per cent) and mafenide acetate 8.5 per cent (MA) were compared to assess the antibacterial effect of once daily application on experimental rat 20 per cent full skin thickness burn wounds seeded 24 h earlier with 10(8) microorganisms originally isolated from infected wounds of burned patients. Separate series evaluated Staph. aureus, Enterococcus faecalis, Enterobacter cloacae and Ps. aeruginosa. The mean concentration of all four organisms recovered after 1 week from full thickness biopsies of eschar and from separate biopsies of subjacent muscle was less in MA and SS + CD 0.2 per cent treated animals compared with those treated with SS alone. The mean concentration in muscle and eschar following treatment with MA was less for wounds seeded with Staph. aureus and Ps. aeruginosa than with SS + CD 0.2 per cent treatment, while the mean concentration in eschar application of SS + CD 0.2 per cent was less than with MA for E. faecalis seeded wounds.

Administration, Topical↗

PubMed1991

Carpentier-Edwards porcine bioprostheses. Comparison of standard and supra-annular prostheses at 7 years.

The performance of the Carpentier-Edwards supra-annular (CE-SAV) porcine bioprosthesis is compared with the Carpentier-Edwards standard (CE-S) porcine bioprosthesis at 7 years. The standard prosthesis was implanted in 1,195 patients between 1975 and 1987, while the supra-annular prosthesis was implanted in 1,956 patients between 1982 and 1989. The total follow-up for the standard prosthesis was 8,850 patient-years with a mean follow-up of 7.4 years, while for the supra-annular prosthesis it was 7,317 years with a mean of 3.7 years. The follow-up for the standard prosthesis was 96.7% and for the supra-annular prosthesis was 97.6%. The freedom from structural valve deterioration (SVD) for aortic replacements is 96.1 +/- 0.9% for CE-S and 97.6 +/- 1.4% for CE-SAV at 7 years (p = NS). The freedom for mitral replacements from SVD is 89.1 +/- 1.7% and 88.6 +/- 2.8%, respectively, for CE-S and CE-SAV (p = NS). The freedom for multiple replacements at 7 years was 80.0 +/- 4.5% for CE-S and 97.8 +/- 1.5% for CE-SAV (p less than or equal to 0.05). The freedom from SVD for the age group equal to or less than 35 years is 79.0 +/- 4.7% for CE-S and 85.0 +/- 9.4% for CE-SAV (p = NS). The freedom for the age group 36-50 years is 85.2 +/- 2.8% and 90.4 +/- 4.5%, respectively, at seven years for the CE-S and CE-SAV prostheses (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗

PubMed1990

Response to allopurinol pretreatment in a swine model of heart-lung transplantation.

The role of allopurinol in the prevention of ischemia-reperfusion injury was assessed in a model of heart-lung transplantation. Fourteen swine were divided into two groups (seven donors and seven recipients). All heart and lung blocks were placed in hypothermic storage after perfusion with cold iso-osmolar cardioplegic solution and modified Collins solution, respectively (t = 8-10 degrees C for heart and t = 16-18 degrees C for lungs). The total ischemic time including the orthotopic transplantation was 6 h. Animals (donors and recipients) were pretreated with allopurinol given orally at a dosage of 50 mg/kg for 4 days. Animals were assessed by monitoring heart and lung function, including extravascular lung water at three time intervals, which included pretransplantation (donor), and 30 min and 2 h posttransplantation (recipient). Erythrocyte peroxidation susceptibility was assessed for 3 days, and surgery was performed on day 4. The malondialdehyde levels determined from erythrocyte exposure to in vitro peroxidative challenge classified three paired donor and recipient animals as responders and four paired donor and recipient animals as nonresponders to the allopurinol pretreatment. A persistent deterioration of lung function was observed over time in nonresponders (p less than .05) (increase of lung water, decrease of partial pressure of oxygen, increase in alveolar-arterial gradient, and decrease in arterial-alveolar tension ratio). Responders showed no significant alterations in lung function. This study in swine, a species devoid of myocardial xanthine oxidase activity, indicates that allopurinol may have a mechanism of action other than xanthine oxidase inhibition in the prevention of ischemia-reperfusion injury. The parallelism between protection of lung function and of red blood cells suggests the involvement of a generalized increase in tissue antioxidant capacity.

Allopurinol↗

PubMed1988

Comparison of standard and chlorhexidine-derivative topical antibacterial agents on the infected burned rat wound.

The effect of daily treatment with three current topical antibacterial agents and four experimental formulations of chlorhexidine was evaluated after 1 week in rats with full thickness burns. The burn was seeded with 1 x 10(8) colony forming units (CFU) of a strain of P. aeruginosa isolated from the infected wound of a burn patient. Mafenide acetate resulted in the lowest incidence of muscle invasion and yielded the lowest mean eschar and muscle concentrations. Mafenide acetate, gentamicin, and chlorhexidine diphosphanilate (0.5 per cent) had lower mean eschar and muscle concentrations than silver sulphadiazine 1 per cent alone. Addition of chlorhexidine digluconate (0.5 per cent or 1.0 per cent) to silver sulphadiazine reduced mean eschar concentrations but not muscle concentrations compared to silver sulphadiazine alone. All treatments effectively suppressed systemic invasion of lung and blood and prevented death compared with controls. Mafenide acetate, gentamicin sulphate and chlorhexidine disphosphanilate 0.5 per cent were most effective against this patient strain of P. aeruginosa.

Administration, Topical↗

PubMed1985

Mechanical preparation of the large bowel for elective surgery. Comparison of whole-gut lavage with the conventional enema and purgative technique.

In this prospective, randomized study, 121 elective colorectal surgery patients had whole-gut lavage (n = 67) or enemas and purgatives (n = 54). Patient characteristics were well matched. Intravenous metronidazole and tobramycin were administered preoperatively initially in 53 patients, with the remaining 68 patients receiving the drugs perioperatively. Bowel preparation was satisfactory (minimal or no contents remaining) in 92.8 percent of patients with whole-gut lavage and 92.6 percent with enemas and purgatives (p = 0.72). Nasogastric tube insertion was poorly tolerated by 39 percent of the patients receiving whole-gut lavage, and enema tube insertion by 23 percent with enemas and purgatives. Fluid infusion tolerance was similar with both techniques. Abdominal wound sepsis occurred in 22 patients (18.8 percent), being unrelated to mechanical preparation or antimicrobial prophylaxis (p = 0.19). Colostomy closure was associated with a 42.8 percent sepsis rate. Excluding this group, wound sepsis with the remaining procedures was 13 percent (statistically significant, p = 0.03). Other complications included intraabdominal abscesses (3.3 percent), anastomotic leaks (2.5 percent), eviscerations (1.6 percent), and an operative mortality of 1.6 percent. We have concluded that whole-gut lavage and enemas and purgatives are equally efficacious mechanically with similar associated wound sepsis rates.

Adolescent↗

PubMedDate not supplied

Major burns managed without blood or blood products.

Four major burns (two flame, one scald, one electrical) were managed without administration of blood or plasma. Serial changes in hemoglobin, and serum albumin and total protein measurements were compared with those of controlled patients matched in age and total body surface area burned who were treated by standard methods. Hemoglobin values were lower but within one standard deviation, although serum protein and albumin measurements fell more than one standard deviation below mean values observed in control patients at comparable times after burn injury. Important treatment principles that were instrumental to recovery include a high-calorie, high-protein diet, iron supplementation, use of pediatric blood sampling techniques, and monitoring for and prophylaxis against infection while allowing eschar to separate spontaneously rather than performing early debridement. Amputation of mummified electrically burned limbs at more proximal levels, including marginally viable muscle, is recommended to minimize infection and decrease blood loss associated with customary conservative serial debridements.

Adult↗

PubMedDate not supplied

Comparison of silver sulfadiazine 1% with chlorhexidine digluconate 0.2% to silver sulfadiazine 1% alone in the prophylactic topical antibacterial treatment of burns.

Wound bacterial colonization in 118 patients treated with chlorhexidine digluconate 0.2% in silver sulfadiazine 1% applied daily to the burn wounds was compared to that of 135 comparable patients similarly treated with silver sulfadiazine 1%. With chlorhexidine digluconate 0.2% in silver sulfadiazine 1%, colonization by Staphylococcus aureus was less frequent (38%) than with silver sulfadiazine (54%, p = 0.016). No statistical difference was found for colonization by Enterococcus faecalis, Pseudomonas aeruginosa, or Enterobacter cloacae. Washing of the wounds of 65 patients with chlorhexidine gluconate 4% during daily dressing changes was associated with reduced wound colonization by S. aureus (35% versus 51%, p = 0.03) and P. aeruginosa (8% versus 16%, p = 0.08) when compared to the 188 washed with nonantibacterial soap. Chlorhexidine, whether added to the topical agent silver sulfadiazine (chlorhexidine digluconate 0.2%) or in the bath soap (chlorhexidine gluconate 4%), decreased colonization by S. aureus.

Administration, Topical↗

PubMedDate not supplied

Valve replacement surgery complicated by acute renal failure--predictors of early mortality.

BACKGROUND: Acute renal failure (ARF) is a serious complication of valve replacement surgery. The aim of this study was to determine the predictors of early mortality and if causative factors are preventable. METHODS: In the 25-year period between 1977 and 2002, 255 (2.6%) of 9721 patients (11,007 operations), who had valve replacement surgery, were managed for ARF with dialysis. The mean age of the patient population was 67.1 +/- 11.6 years (range 24 to 87 years, median 70.3 years). Fifty preoperative, operative, and postoperative risk factors were assessed as predictors of early mortality by univariate and multivariate modeling. RESULTS: The early mortality was 25.1% (64 patients). The predictors by univariate analysis were: New York Heart Association class (p = 0.001); ASA within 5 days (p = 0.030); cardiogenic shock (p = 0.010); infection--perioperative sepsis and preoperative endocarditis (p = 0.000); intraoperative stroke (p = 0.003); status--emergent (p = 0.000); mitral valve replacement (p = 0.040); ischemic (X-clamp) time >120 minutes (p = 0.020); cardiopulmonary bypass time >180 minutes (p = 0.000); surgical time >360 minutes (p = 0.000); surgical hemorrhage (p = 0.020); acute respiratory distress syndrome (ARDS) (p = 0.040). Multivariate predictors were urgent status of operation, odds ratio (OR) 0.3 (p = 0.029); emergent status of operation, OR 5.8 (p = 0.034); ischemic (X-clamp) time >120 minutes, OR 4.4 (p = 0.030); surgical time >360 minutes, OR 6.3 (p = 0.019); surgical hemorrhage, OR 5.1 (p = 0.003); perioperative nosocomial sepsis, OR 3.8 (p = 0.006); and preoperative endocarditis, OR 4.4 (p = 0.004). CONCLUSIONS: Early mortality from ARF in valve replacement surgery is related to emergent status, ischemic and surgical times, surgical hemorrhage, and nosocomial infection/preoperative endocarditis. Among the variables assessed, preoperative renal insufficiency, unstable angina/recent myocardial infarction <6 weeks, and concomitant coronary artery bypass were not predictive. The evaluation of predictors of ARF requires further extensive assessment.

Acute Kidney Injury↗

PubMedDate not supplied

Comparison of new iron chelating agents in the prevention of ischemia/reperfusion injury: a swine model of heart-lung transplantation.

The preservation of the heart and lung for transplantation remains a major concern in extended ischemic intervals. This experimental endeavor evaluates and compares the efficacy of iron chelating agents such as high molecular weight deferoxamine and 21-aminosteroid (U74006F) in a swine model of heart-lung transplantation. Heat-lung blocks were exposed to 4 h and 45 min of ischemia and 2 h of reperfusion. Animals were divided into three groups. Group A was a control without pharmacological intervention. In groups B and C, 21-aminosteroid (U74006F), 10 mg/kg, and high molecular weight deferoxamine, 50 mg/kg, were used, respectively. The results of functional parameters (cardiac index, stroke index, lung water, PO2, PCO2, alveolar-arterial gradient, and alveolar-arterial ratio) demonstrated superior heart and lung function for group C, where high molecular weight deferoxamine was used. Alterations of heart and lung function were significantly more (p less than .001) for control animals and for group B where U74006F was used. This study suggests that formation of hydroxyl radicals was affected by chelation of iron with high molecular weight deferoxamine, which reflects better heart and lung function and consequently less damage to this group of animals. The compound 21-aminosteroid U74006F failed to protect the heart and lung from ischemic-reperfusion injury in this model of heart-lung transplantation.

Animals↗

PubMedDate not supplied

Cultured epithelial autografts: three years of clinical experience with eighteen patients.

Eighteen patients with major burns (mean total body surface area burned was 49% and mean total body surface area with full-thickness burns was 38%) had cultured epithelial autografts applied to 2% to 35% of the body surface area. In six patients successful "take" of greater than 65% occurred, and in 12 patients less than 40% "take" occurred. Most wounds underwent early excision to subcutaneous fat or fascia, and the wounds of 16 patients had been treated previously with homograft. Cultured epithelial autografts were covered with either single or multilayered dressings. Perioperative wound cultures showed that all patients had microorganisms, and appropriate perioperative antibiotic coverage of Staphylococcus epidermidis and Pseudomonas aeruginosa was noted less frequently in the poor take group, which may have influenced subsequent cultured epithelial allograft take. Adherence and stability of cultured epithelial allografts lag behind adherence and stability of meshed split-thickness autograft. The anterior trunk and thighs are the best recipient sites. The number of autograft harvests that were required to close wounds and the length of hospital stay were not significantly decreased by the use of cultured epithelial allografts as compared with comparable full-thickness burns that were treated previously without cultured epithelial allografts. Presently, grafting with cultured epithelial allografts is an adjunct but not an alternative to conventional burn-wound coverage with split-thickness autograft, because engraftment is inconsistent.

Adolescent↗