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Biomedical subjects

T Niemi

Publications and source records attributed to T Niemi.

At least 19 recordsLinked to original sources
PubMed2004

Endovascular vs open AAA repair: similar effects on renal proximal tubular function.

AIM: To compare the effect of open and endovascular repair on renal function. MATERIALS AND METHODS: In a prospective, non-randomized study twenty-four abdominal aortic aneurysms (AAA) treatable with either method were repaired, 15 using endovascular device (ENDO group) and nine with open surgery with infrarenal aortic cross-clamping (OPEN group). All the patients had standardised general anaesthesia, intravascular fluid therapy and monitoring. Renal function tests and cardiovascular measurements were performed at predetermined intervals. RESULTS: N-acetyl-beta-D-glucosaminidase indexed to urinary creatinine (U-NAG/crea), a sensitive marker of renal proximal tubular damage, increased similarly in both groups at the end of surgery (two-way ANOVA, p < 0.05). No patient developed clinical renal impairment, on the contrary, creatinine clearance was increased, serum cystatin C (a sensitive marker of renal glomerular filtration) and serum creatinine concentration decreased at 24 hours postoperatively (Wilcoxon paired test, p < 0.05). Intraoperative blood loss and the amount of administered crystalloids were higher in the OPEN than in the ENDO group (Mann-Whitney U-test, p < 0.05). The cardiovascular measurements were comparable between the groups. The mean (SD) amount of radio-contrast media given was 3.1 (1.1) ml/kg in the ENDO group. CONCLUSIONS: Our results indicate that endovascular AAA repair does not protect renal proximal tubular function. A temporary renal tubular dysfunction was found both in open and in endovascular AAA repair which did not lead to permanent changes in renal function.

Acetylglucosaminidase↗
PubMed1999

Effects of nonsteroidal anti-inflammatory drugs on hemostasis in patients with aneurysmal subarachnoid hemorrhage.

Platelet function is impaired by nonsteroidal anti-inflammatory drugs (NSAIDs) with prominent anti-inflammatory properties. Their safety in patients undergoing intracranial surgery is under debate. Patients with aneurysmal subarachnoid hemorrhage (SAH) were randomized to receive either ketoprofen, 100 mg, three times a day (ketoprofen group, n = 9) or a weak NSAID, acetaminophen, 1 g, three times a day (acetaminophen group, n = 9) starting immediately after the diagnosis of aneurysmal SAH. Treatment was continued for 3 days postoperatively. Test blood samples were taken before treatment and surgery as well as on the first, third, and fifth postoperative mornings. Maximal platelet aggregation induced by 6 microM of adenosine diphosphate decreased after administration of ketoprofen. Aggregation was lower (P < .05) in the ketoprofen group than in the acetaminophen group just before surgery and on the third postoperative day. In contrast, maximal platelet aggregation increased in the acetaminophen group on the third postoperative day as compared with the pretreatment platelet aggregation results (P < .05). One patient in the ketoprofen group developed a postoperative intracranial hematoma. Coagulation (prothrombin time [PT], activated partial thromboplastin time [APPT], fibrinogen concentration, and antithrombin III [AT III]) was comparable between the two groups. Ketoprofen but not acetaminophen impaired platelet function in patients with SAH. If ketoprofen is used before surgery on cerebral artery aneurysms, it may pose an additional risk factor for hemorrhage.

Acetaminophen↗
PubMed1999

Use of the Heimlich valve for treating pneumothorax.

BACKGROUND AND AIMS: The aim of this retrospective study was to compare the use of a small caliber tube connected to Heimlich flutter valve with a conventional thoracic drainage system in the treatment of pneumothorax. MATERIALS AND METHODS: Patients with simple pneumothorax during the years 1991-1995 in Satakunta Central Hospital were included in this study. Nineteen patients were treated with the Heimlich flutter valve and 57 patients were treated with the standard drainage tube connected to an underwater seal device. The data were collected from hospital records focusing on the duration of chest drainage, the number of chest roentgenograms and the length of hospital stay. RESULTS: In the Heimlich valve group the mean drainage time was 2,2+/-0.9 days and in the standard thoracic drainage group 3.4+/-3.8 days (p <0.05) respectively. The mean length of hospitalization in the Heimlich valve group was 3.3+/-2.2 days and in the standard thoracic drainage group 5+/-4.9 days (p < 0.01). The number of chest roentgenograms in the Heimlich valve group was 3+/-1.1 and in the standard thoracic drainage group 4.6+/-2.7 (p < 0.001). CONCLUSION: We believe that the treatment with a small caliber tube and Heimlich valve is a safe and effective procedure. It also reduces the duration of chest drainage and the length of hospital stay.

Adult↗
PubMed1998

Haemostatic disturbances in burned patients during early excision and skin grafting.

Bleeding is a major problem during early excision of burned skin. Therefore, 13 severely burned adult patients operated on during the first week after the trauma were studied. Blood loss was replaced with crystalloids, colloids and packed red cell concentrates (PRC). After ten infused PRCs, four fresh frozen plasma (FFP) units were given and thereafter one FFP unit with one PRC unit. Arterial blood samples were drawn before anaesthesia (SO), during operation after every four units of PRC transfusion (S1-4), 4 h postoperatively (S5) and on the first postoperative morning (S6). Prothrombin time (%) and activated partial thromboplastin time (s) were abnormal before operation (median values 67%, range 22-99% and 44 s, range 30-86 s, respectively). Prothrombin time decreased during operation and reached the critical level for normal haemostasis at S2. Thrombelastography showed decreased clot formation rate and impaired fibrin platelet interaction peri- and postoperatively. Fibrinogen and factor VIII activity were high preoperatively (median 6.1 g/l and 253%) and the critical values for normal haemostasis were not reached. Burned patients have a consumption coagulopathy which, in combination with haemodilution during operation, results in a clinically significant deficiency of coagulation factors II, VII and X, in spite of reactive elevation of coagulation factor VIII and fibrinogen.

Adult↗
PubMed1997

Traumatic injuries among university students in Finland.

A questionnaire dealing with the incidence of traumatic injuries was sent to 1,000 randomly selected 3rd-year university students in Finland; 617 students responded adequately. Of those, 177 (28.7%) reported a combined total of 281 accidents and 323 separate injuries requiring medical or dental treatment during the preceding 3 years. The accidents resulted in 1,061 days of official sick leave, and one third of the accidents caused permanent sequelae to the affected students. Almost half of all accidents had been sustained during sports activities and 14% in traffic. Only 0.5% of the accidents were classified as having occurred in the university environment or during activities directly related to studies. Alcohol was involved in 10.1% of the accidents; 45% of the injuries affected the lower extremities, and 22% the upper extremities. Most of the injuries were related to the students' active lifestyles and keen interest in sports.

Accidents, Traffic↗
PubMed1993

Suicides among university students in Finland.

This study is part of a nationwide research project dealing with all suicides in Finland. It includes all suicides among university students during the 1-year period from April 1, 1987, to March 31, 1988. Ten students (6 men and 4 women) committed suicide during the period studied. The observed suicide rates per 100,000 students per year were 13.8 (95% CI = 5.1-30.1) for men and 9.0 (95% CI = 2.4-22.8) for women. The difference between the observed and expected suicide rate for men (13.8 v 47.7, standard mortality rate [SMR] = 29) was statistically significant. For women (9.0 v 8.3, SMR = 108), the difference was not statistically significant. Most of the suicides had experienced serious difficulties since early childhood, including narcissistic problems, difficulties in human relations, severe depressive periods, previous suicidal behavior, and alcohol problems; they had also had earlier psychiatric treatment.

Adolescent↗
PubMed1983

Resting and exercise renal blood flows in immature ovine aortic coarctation. Impact of gradient relief.

The primary purpose of this study was to determine whether a neonatally induced thoracic aortic coarctation reduces renal blood flow during physiological stress (treadmill exercise), and whether relief of the gradient returned renal blood flow during exercise to normal. Two ancillary questions were also addressed: dose a coarctation after the responses of enteric and other visceral vascular beds to treadmill exercise? Eight newborn lambs that underwent sham thoracotomy with placement of left atrial lines served as controls; in seven lambs we also created a recently described form of dilatable juxtaductal coarctation. This preparation is unique in that, like human coarctation, the obstruction does not get worse as the animal grows. Rest and exercise vascular pressures and regional blood flows were determined 2-2 1/2 months after surgery. Coarctations were relieved with balloon dilation angioplasty catheters, inserted percutaneously. Postdilation rest and exercise hemodynamic studies were performed, at the same level of exercise, 24 hours after dilation. Renal blood flow did not change with exercise in the control animals. In lambs with coarctation, renal blood flow fell (-22%, P less than 0.01) during exercise. Unexpectedly, an exercise-induced fall in renal blood flow (-22%, P less than 0.001) persisted even after effective relief of the coarctation (descending aortic blood pressure fell 25% with exercise predilation, but remained unchanged with exercise postdilation). Blood flow to the terminal ileum and cecum followed a qualitatively similar pattern to that of renal blood flow in control, predilation, and postdilation lambs, and this pattern was distinct from that of other enteric and visceral organ flows. These results demonstrate an expected abnormality in the regulation of exercise renal blood flow in lambs with coarctation of the aorta; however, the persistence of this abnormality after effective gradient relief does not support the previously advanced theory that postcoarctation hypertension is largely nonrenal in origin. The apparent similarity between ileocecal and renal blood flow control under these circumstances may provide a clue to the known predilection of the terminal ileum to suffer ischemic injury.

Animals↗
PubMed1982

Transcutaneous angioplasty of experimental aortic coarctation.

A dilatable form of juxtaductal aortic coarctation was surgically created in 29 newborn lambs. Of the 17 long-term survivors, four lambs served as controls and 13 underwent transcutaneous balloon dilation angioplasty with either polyvinylchloride or polyethylene catheters after 7--10 weeks of recovery. During growth before dilation, there was little change in the systolic gradient across the coarctation (36.6-35.3 mm Hg) despite an increase in animal weight from 3.8 to 19.3 kg. This systolic gradient remained constant in undilated lambs throughout a 6-month follow-up. Dilation produced an immediate 65% increase in the diameter of the coarctation and a 68% decrease in the systolic gradient across the coarctation site. Successful dilation required very high (6--8 atmospheres) dilating pressures. This gradient relief persisted throughout a follow-up of up to 1 year. Although no late sequelae could be attributed to the angioplasty, one lamb suffered an anterior aortic tear (associated with a difficult postdilation wire passage across the dilation site), which resulted in fatal intrathoracic hemorrhage. Cross pathologic inspection demonstrated intimal and medial tears in successfully dilated lambs in the first 3 days after dilation; on late pathologic examination, the intima appeared completely healed, without evidence of aneurysm or accelerated atheroma formation, within 2 months. These results, in conjunction with previous human in vitro studies, support the hypothesis that human aortic coarctation may be a dilatable lesion, although the safe limits and optimal protocols for dilating human coarctations are not known.

Angioplasty, Balloon↗
PubMed1981

Purification and some properties of inorganic pyrophosphatase from Streptococcus faecalis.

Inorganic pyrophosphatase [EC 3.6.1.1] from Streptococcus faecalis ATCC 8043 was purified to homogeneity as judged by slab gel electrophoresis in the presence and absence of sodium dodecyl sulfate. The purification consisted of the following steps: streptomycin sulfate precipitation, (NH4)2SO4 treatment in a Sepharose CL-4B column, DEAE-Sepharose CL-6B chromatography, gel filtration on Ultrogel AcA 34, and preparative slab gel electrophoresis. Gel filtration on Ultrogel AcA 34 was used to determine the molecular weight and slab gel electrophoresis in the presence of sodium dodecyl sulfate to study the subunit molecular weight. The enzyme appeared to be composed of four subunits with molecular weights of approximately 32,500. The molecular weight of the native enzyme was about 128,000. The enzyme catalyzed the hydrolysis of inorganic pyrophosphate, and no activity was found with a variety of other phosphate esters. The cation Mg2+ was required for maximum activity; Co2+ and Ca2+ supported 24% and 5.6% of the activity observed with Mg2+, respectively. 2,4,6-Trinitrobenzene sulfonic acid inhibited the reductants containing SH-groups activated the enzyme suggesting that lysine and cysteine have essential roles in the enzyme.

Cations, Divalent↗
PubMed1981

Transvenous angioplasty of experimental branch pulmonary artery stenosis in newborn lambs.

A dilatable form of bilateral branch pulmonary artery stenosis was created in 27 newborn lambs. Nine lambs were long-term survivors and were dilated with modified Grüntzig balloon dilation catheters. They were allowed to recover for 6-9 weeks, during which time there was no significant change in the mean systolic gradients across the narrowed sites. Thirteen arteries underwent dilation. Dilation was associated with a decrease in the systolic gradient in all cases (from 34.9 mm Hg to 8.1 mm Hg) and an increase in the diameter of the narrowed site (from 4.6 to 7.6 mm) as estimated by angiography. Flows and flow distribution were measured in four lambs before and after unilateral dilation using 15-mu radiolabeled microspheres; in each case, the fraction of total flow to the dilated lung rose after dilation (19.2 to 45.4%), as did the total flow to the dilated lung (30.0 to 69.2 ml/kg-min). Four lambs were catheterized every 2-4 weeks for an average of 16 weeks after dilation; the average gradient in these lambs remained below 10 mm Hg despite considerable growth (from 9.6 to 25.9 kg). Gross pathologic examination showed an intact vascular adventitia in all cases; there were multiple linear tears in the intima in recently (less than 7 days) dilated cases, but complete intimal healing had occurred by 2 months after dilation. No significant morbidity could be attributed to the dilation procedure. These results indicate that clinical trials are warranted.

Angioplasty, Balloon↗
PubMed1980

Retirement and mortality.

The present study investigated the effects of retirement on the mortality of the retired. The basis of retirement for the present subjects was in all cases age, not sickenss. The subjects were 1176 men retired on old age pension. In the present study, retirement could not be shown to have any long-term or short-term effects on mortality pointing to retirement not being such a stress situation as to result in an increase in mortality.

Aged↗
PubMed1979

Effect of loneliness on mortality after retirement.

In the present study, the effect of the type and number of available objects on post-retirement mortality was examined. The hypothesis is that the fewer available objects people have upon retirement, the greater will be the mortality after the retirement. The material was divided into three groups: married (assumed to have the greatest object potential), widowed or divorced (second greatest), and single (least potential). The material consisted of men retired on old age pension in 1964. Of these, 792 were married, 119 were widowed or divorced, and 77 were single. No statistically significant differences in mortality between groups on the basis of marital status could be found, although the results tended to favour the hypothesis. The number of suicides and accidents in the group of men dying within two years of retirement exceeded the expected values, but this increase was distributed fairly evenly between groups on the basis of marital status.

Aged↗
PubMed1979

The mortality of male old-age pensioners following spouse's death.

The effect of the death of the spouse on mortality of retired men was investigated. The material comprised 939 married men retired on old age pension, 174 of whom had lost their spouse after retirement. During the first six months following the wife's death, more than the expected number died, though no increase in mortality could be shown over a longer term. Circulatory diseases and tumours were over-represented as causes of death among those who died within six months of the wife's death. Loss of an important object relationship may lead to sudden cardiac death, or the development of a disease may be accelerated.

Aged↗