PubMed Health⌕ Search

Biomedical subjects

J M Klaase

Publications and source records attributed to J M Klaase.

At least 19 recordsLinked to original sources
PubMed2003

Lesion progression with time and the effect of vascular occlusion following radiofrequency ablation of the liver.

BACKGROUND: The effectiveness of radiofrequency ablation (RFA) under selective vascular occlusion and its effects on architecture and viability of normal liver parenchyma was studied in a porcine model. METHODS: RFA was applied in the liver under general anaesthesia in 18 pigs. Six animals were killed immediately after the procedure and 12 at 24 h. RFA was performed sequentially under four conditions: (1) without vascular occlusion, (2) during occlusion of the hepatic artery, (3) during occlusion of the portal vein and (4) during occlusion of the hepatic artery and portal vein. Liver biopsies from the treated area were stained for conventional histological examination, reduced nicotinamide adenine dinucleotide diaphorase and 5'-nucleotidase activity. RESULTS: Vascular occlusion significantly increased the size of the coagulation centre after RFA. Combined portal venous and arterial occlusion had no additional effect on lesion size compared with venous or arterial occlusion alone. After 24 h, deterioration of viability was observed in the parenchyma up to 3 cm from the coagulated area. CONCLUSION: The efficacy of RFA in liver increases with occlusion of the portal vein or hepatic artery. The extent of secondary heat-induced necrosis in liver parenchyma should be considered for determination of the final size of the ablated area.

Animals↗
PubMed2003

Surgery for unusual histopathologic variants of esophageal neoplasms: a report of 23 cases with emphasis on histopathologic characteristics.

BACKGROUND: Adenocarcinoma and squamous cell carcinoma are the most frequent pathologic diagnoses with esophageal malignancy. Unusual pathologic variants are encountered in only 1% to 7% of patients, and therefore data evaluating the treatment and survival in this group of esophageal neoplasms are sparse. METHODS: To get more insight into the unusual pathologic variants, patients were selected from our computer-assisted database containing data from 426 consecutive patients treated with esophageal resection or enucleation at our institute during 1993 to 2000. RESULTS: Uncommon variants of esophageal neoplasms were encountered in 23 patients (5.3%). The following unusual histopathologic variants were seen: basaloid squamous cell carcinoma (n = 3), small-cell carcinoma (n = 1), leiomyoma (n = 5), gastrointestinal stromal tumor (n = 2), leiomyosarcoma (n = 1), adenosquamous carcinoma (n = 5), carcinosarcoma (n = 4), collision tumor (n = 1), and melanoma (n = 1). Presentation, histopathologic characteristics, treatment, and prognosis are described in reference to the existing literature. CONCLUSIONS: Survival data of the unusual pathologic variants seem to be comparable to those of the most frequently encountered neoplasms. Only in case of small-cell carcinoma does there seem to be a definite role for chemotherapy, especially in a multimodality treatment protocol.

Adult↗
PubMed2001

[Local and regional in-hospital trauma care following fireworks depot explosion in Enschede].

UNLABELLED: On Saturday 13 May, 2000 at about 15:30 h, the Dutch city of Enschede was struck by the explosion of a midtown firework depot. Twenty-two people were killed and almost 1,000 people were wounded. A complete district with 1,000 houses was destroyed. In total, 527 victims were treated in one of the regional hospitals, 76 (14%) of whom were admitted and 451 (84%) were treated as outpatients. Of the clinically treated victims, 11 patients were triaged as T1 and needed immediate intervention, 63 patients were triaged as T2 where treatment within six hours was indicated, and two T3 patients did not need urgent treatment. The outpatients mainly suffered secondary blast injuries to the head and extremities due to flying debris. Of the 11 T1 patients, 10 underwent acute surgery; intervention radiology was performed in one patient. The injuries of the severely wounded T1 patients consisted of penetrating thoracic, abdominal and skull injuries, as well as blunt abdominal trauma and compound fractures. Two patients from the disaster area underwent acute vascular surgery for acutely burst aortic aneurysms. The in-hospital trauma care was characterised by the spontaneous arrival of a large number of extra medical personnel. The regional distribution of the trauma patients was adequate. The regional capacity of the emergency rooms, IC-units and operating facilities proved to be sufficient. Routing of lightly-wounded patients was found to be important. The communication in all phases of the disaster management appeared to be poorly structured. CONCLUSION: During the initial trauma care, the routing of vast numbers of ambulant, lightly-wounded patient, as well as extra doctors and nurses, needs careful planning.

Adolescent↗
PubMed2001

[Injury to the right A. pulmonalis due to blunt thoracic trauma].

Immediately after a moped accident a 16-year old patient was haemodynamically unstable. Following adequate drainage of a haematopneumothorax in the hospital the patient collapsed into a shock. Thoractomy revealed a tear of the right A. pulmonalis. The hilus was clamped and a lobectomy was performed. After this the patient was haemodynamically stable; due to bone and nerve damage he was transferred to a rehabilitation centre. Laceration of the A. pulmonalis as a consequence of blunt thoracic trauma is rare and mostly fatal. In the case of a patient with a massive haematothorax rapid transport to the nearest hospital is preferable to thorax drainage at the site of the accident.

Accidents, Traffic↗
PubMed2001

Regional toxicity after isolated limb perfusion with melphalan and tumour necrosis factor- alpha versus toxicity after melphalan alone.

AIMS: To determine whether the addition of high-dose tumour necrosis factor-alpha (TNF alpha) to isolated limb perfusion (ILP) with melphalan increases acute regional tissue toxicity compared to ILP with melphalan alone. METHODS: A retrospective, multivariate analysis of toxicity after normothermic (37--38 degrees C) and 'mild' hyperthermic (38--40 degrees C) ILPs for melanoma was undertaken. Normothermic ILP with melphalan was performed in 294 patients (70.8%), 'mild' hyperthermic ILP with melphalan in 71 patients (17.1%) and 'mild' hyperthermic ILP with melphalan combined with TNF alpha in 50 patients (12.0%). Toxicity was nil or mild (grades I--II according to Wieberdink et al.) in 339 patients (81.7%), and more severe acute regional toxicity (grades III--V) developed in 76 patients (18.3%). A stepwise logistic regression procedure was performed for the multivariate analysis of prognostic factors for more severe toxicity. RESULTS: On univariate analysis, 'mild' hyperthermic ILP with melphalan plus TNF alpha significantly increased the incidence of more severe acute regional toxicity compared to normothermic and 'mild' hyperthermic ILP with melphalan alone (36% vs 16% and 17%; P=0.0038). However, after ILP using TNF alpha no grade IV (compartment compression syndrome) or grade V (toxicity necessitating amputation) reactions were seen. Significantly more severe toxicity was seen after ILPs performed between 1991 and 1994 compared with earlier ILPs (33%vs 14%P=0.0001). Also, women had a higher risk of more severe toxicity than men (22% vs 7%; P=0.0007). After multivariate analysis, prognostic factors which remained significant were: sex (P=0.0013) and either ILP schedule (P=0.013) or treatment period (P=0.0003). CONCLUSIONS: Regional toxicity after 'mild' hyperthermic ILP with melphalan and TNF alpha was significantly increased compared to ILP with melphalan alone. This may be caused by increased thermal enhancement of melphalan due to the higher tissue temperatures (39--40 degrees C) at which the melphalan in the TNF alpha-ILPs was administered or by an interaction between high-dose TNF alpha and melphalan.

Adult↗
PubMed2000

Monitoring of impending myocardial damage after pleuropneumonectomy and intraoperative photodynamic therapy for malignant pleural mesothelioma using biochemical markers.

In five patients who were treated for malignant pleural mesothelioma (MPM) with pleuropneumonectomy and intraoperative photodynamic therapy (IPDT), impending myocardial damage was monitored using ECG, the classical biochemical markers (creatine kinase [CK], total activity; CKMB, mass; and myoglobin), and the new cardiac markers troponin I (cTnI) and troponin T (cTnT). In the peroperative and postoperative period all classical markers were elevated, in contrast to cTnI and cTnT, because of the concomitant skeletal muscle damage. Sequential electrocardiogram monitoring showed no signs of myocardial damage. From this study in patients with MPM treated with pleuropneumonectomy and IPDT it can be concluded that measurement of cTnI and cTnT for the detection of myocardial damage is more suitable than measurement of the classical markers.

Biomarkers↗
PubMed1999

Relation between limb toxicity and treatment outcomes after isolated limb perfusion for recurrent melanoma.

BACKGROUND: The optimal toxic reaction of the normal tissues in perfused limbs after isolated limb perfusion (ILP) is unknown. Theoretically, more severe limb toxicity could reflect a concomitant increased toxic effect to the tumor and improved outcomes. We determined whether there is a relation between limb toxicity and treatment outcomes after ILP for recurrent limb melanoma. STUDY DESIGN: Among 252 patients with recurrent melanoma of the limbs, treatment outcomes in 192 patients (76%) with no or mild acute limb toxicity were compared with those in 60 (24%) with more severe reactions. Multivariate analysis was used to identify prognostic factors for complete response, limb recurrence-free interval, and survival. RESULTS: Among 112 patients with measurable disease, 65 patients (58%) had a complete response and 27 (42%) experienced a relapse in the perfused limb. For complete response, uninvolved regional lymph nodes (p = 0.0025) and ILP using tumor necrosis factor-alpha (p = 0.0076) appeared to be favorable prognostic factors in multivariate analysis. There was no evidence of a relation between limb toxicity and complete response either in univariate (p = 0.16) or multivariate analysis (p = 0.46). For limb recurrent-free interval, only the number of lesions was a significant prognostic factor (p = 0.047); limb toxicity was not (p = 0.095). In 140 patients with recurrent melanoma excised before or at the moment of ILP, independent prognostic factors for survival were gender, the number of positive nodes, and stage of disease. There was no relation between limb toxicity and survival in either univariate (p = 0.53) or multivariate analysis (p = 0.94). Forty-eight (34%) of the 140 patients had a relapse in the perfused limb. No prognostic factors for limb recurrent-free interval could be identified; limb toxicity was not related to relapse time in univariate or multivariate analyses (p = 0.16 and p = 0.14, respectively). CONCLUSIONS: More severe acute limb toxicity is not associated with improved outcomes. One should aim at grade II toxicity (slight erythema or edema, compatible with complete recovery) at the most to increase the therapeutic ratio of ILP.

Adolescent↗
PubMed1998

Troponin I, troponin T, CKMB-activity and CKMB-mass as markers for the detection of myocardial contusion in patients who experienced blunt trauma.

Myocardial contusion is an infrequent, but sometimes serious complication in patients who experienced deceleration (blunt) trauma. We investigated the assessment of the new cardiac markers troponin I (cTnI) and troponin T (cTnT) in relation to the conventional CKMB-activity, the CKMB-activity/CK-total ratio, CKMB-mass and the CKMB-mass/CK-total ratio for the detection of myocardial contusion in 89 patients with blunt trauma (38 patients with thoracic injuries and 51 patients without thoracic injuries). All parameters were analysed at admission (t1) and 24 h after admission (t2). For the patients with thoracic injuries, at t1 cTnI was elevated in three, and cTnT in four patients; at t2 both cTnI and cTnT were elevated in nine patients. At t1, eighteen to thirty patients had increased levels of the conventional parameters; at t2 this was true for six to thirty-five patients. For the patients without thoracic injuries all cTnI and cTnT levels were within the reference ranges at t1. At t2 one patient, who experienced an acute myocardial infarction, had elevated cTnI and cTnT levels. At t1, five to thirty-five patients had increased levels of the conventional parameters; at t2 this was true for four to forty-two patients. From this study we conclude that the conventional parameters are not useful for the detection of myocardial contusion in patients experiencing blunt trauma. The parameters cTnI and cTnT are equally accurate and more reliable for the selection of patients who require intensive cardiac monitoring. If at admission the cTnI or the cTnT levels are within the reference ranges, a second analysis after admission is necessary to reach a reliable conclusion concerning myocardial contusion as a result of trauma on basis of the troponin levels.

Adolescent↗
PubMed1998

[The elevation of serum creatine kinase-MB level in trauma patients: misleading impression of myocardial damage].

OBJECTIVE: To determine the frequency of increase of serum values, not of cardiac origin, of creatine kinase-MB (CK-MB) in trauma patients. DESIGN: Prospective. SETTING: University Hospital, Groningen, the Netherlands. METHODS: 51 trauma patients without chest injury (without myocardial contusion) but with (among others) soft tissue injuries, were included. At admission (time point t1) an ECG and chest X-ray were made and blood was collected for measurement of CK total, CK-MB activity and CK-MB mass. If the CK-MB activity/CK total fraction exceeded 3%, CK electrophoresis was performed. Blood analysis was repeated after 24 hours (t2). RESULTS: CK-MB activity was elevated in 27 patients (53%) at t1 and in 3 (6%) at t2. The fraction CK-MB activity/CK total exceeded 3% in 96% and 33% of these patients at t1 and t2, respectively. In all these cases a CK-BB band was detected by electrophoresis (CK-BB interferes with the CK-MB activity measurement). CK-MB mass was elevated in 11 patients (22%) at t1 and in 19 (37%) at t2. CONCLUSION: CK-MB was frequently elevated in trauma patients owing to skeletal muscle damage and to interference with CK-MB activity measurements. For the detection of myocardial damage in trauma patients, CK-MB measurements are of little use.

Adolescent↗
PubMed1998

[Thyroglossal cyst].

The thyroglossal cyst is a wellknown cause of a swelling in the neck. The generally accepted technique of treatment was described in 1928, but many recurrences are still seen in daily clinical practice. The radical technique of removal of cysts and sinuses of the thyroglossal duct according to Sistrunk is the method of choice. Over an 8-year period 40 cases were treated in this fashion in the University Hospital Groningen, the Netherlands, with an average follow-up of 5 years and 3 months; in 29 it was the first operation. Only 1 patient of the 23 treated according to Sistrunk had a recurrence for which he had to be treated again. Six patients were treated otherwise; 3 of them had a recurrence. It is concluded that the first surgery (according to Sistrunk), if correctly performed, offers the best chance for cure.

Adolescent↗
PubMed1998

Increased kyphosis by a combination of fractures of the sternum and thoracic spine.

A 67-year-old patient suffered a fall and sustained injuries to the thorax, combined with fractures of the ribs, sternum and thoracic spine. Her pre-existing kyphosis (caused by osteoporotic vertebral collapse) increased in severity. There was a clear relationship between a sternal fracture, deterioration of thoracic kyphosis and a fracture of the thoracic spine.

Accidental Falls↗
PubMed1997

[Toe tourniquet syndrome].

In two boys aged 4 months and one girl aged 2 months one or two toes were red and oedematous, while in one boy aged 3 weeks one toe had become necrotic. In the first-mentioned three children the affected toes were encircled by a hair, the hair was removed under anaesthesia, after which the children recovered. In the last-mentioned child, amputation through the proximal phalanx was necessary. The toe tourniquet syndrome occurs mainly in infants. Strangulation of the toes by circular foreign material. such as hair or fibre, causes oedema and increasing constriction. Timely treatment is followed by good recovery. Delayed or incomplete treatment can lead to necrosis which may necessitate amputation.

Constriction, Pathologic↗
PubMed1997

Value of laboratory tests in monitoring acute regional toxicity after isolated limb perfusion.

BACKGROUND: Severe limb toxicity following isolated limb perfusion (ILP) can lead to compartmental compression syndrome and severe rhabdomyolysis, occasionally necessitating amputation of the affected limb. We determined whether laboratory tests for muscle damage and inflammation could predict impending limb toxicity. METHODS: All 184 consecutive ILPs performed in our institute from 1988 to 1994 were included in this study. Creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (ASAT) and white blood cell (WBC) counts were determined on post-ILP days 1-4, 6, 8, and 15. RESULTS: "Late peak" CK patterns, characterised by a peak on or after the 5th post-perfusion day, were strongly associated with severe limb toxicity (p < 0.001). Severe toxicity did develop in 40% of the limbs when CK values exceeded 1000 IU/L on the 2nd to 5th post-ILP day (p < 0.001). There was a correlation between the peak CK and the individual grades of toxicity (r = 0.6, p < 0.001). Serum LDH and ASAT values peaked 2.9 and 3.4 days after the CK peak respectively. Severe limb toxicity was statistically significantly associated with higher WBC counts from the 2nd post-ILP day onwards. CONCLUSIONS: CK values exceeding 1000 IU/L after the 1st and WBC counts increasing after the 2nd post-ILP day could be predictors of impending limb toxicity. These patients should be observed closely for signs of compartmental compression syndrome and severe rhabdomyolysis.

Adult↗
PubMed1996

Systemic toxicity after isolated limb perfusion with melphalan for melanoma.

Systemic exposure to melphalan is minimized during isolated limb perfusion (ILP) by isolating a limb from the rest of the body. Consequently, there should be no toxicity to vital organs. At present systemic toxicity after ILP has not been studied in detail. Therefore, the incidence, nature and risk factors of systemic toxicity was retrospectively studied in 368 patients who underwent a single ILP with melphalan between 1978-1990. Some form of systemic toxicity occurred in 98 patients (27%). Nausea and vomiting after the 1st post-ILP day was seen in 73 patients (20%), and in seven (2%) treatment was required. Bone marrow depression was encountered in seven patients (2%): WHO grade II in five, and grade III in two. Miscellaneous systemic side-effects, including fever and minimal scalp hair loss, occurred in 19 patients (5%). Leakage from the isolated circuit to the systemic circulation was measured with radioactive tracers. Mean cumulative leakage during ILP was 0.9%. Systemic toxicity was not increased in patients with leakage greater than 1% or 5%. Female sex was associated with an increased incidence of systemic toxicity (P<0.05). Age over 60 years (P<0.05) and more severe acute regional toxicity (P<0.05) were correlated with nausea and vomiting. The miscellaneous systemic side-effects were more frequently encountered in women than in men (P<0.05). In conclusion, systemic toxicity was rarely severe, with nausea and vomiting being the most frequently encountered side-effects. Age over 60 years, female sex and more severe acute regional toxic reactions were correlated with an increased incidence of systemic side-effects. Systemic leakage during ILP was not associated with toxicity, probably due to the low incidence of significant leakage.

Adolescent↗