Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Filtering Surgery”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,639 records · Page 91Linked to original sources
PubMed1994

[Autologous blood transfusion in tumor operations].

OBJECTIVE: The potential and limits of autologous transfusion in tumor patients are discussed according to the literature. New aspects are derived from own recent studies. DATA SOURCES AND SELECTION CRITERIA: The critical review of the German and English literature is based on a Medline and DIMDI backsearch covering the last 20 years. Own data not yet published are presented. RESULTS: Predeposit autologous blood represents an important and practical alternative to homologous transfusion also for tumor patients. Predeposit programs are limited by tumor anemia, the urgent time schedule for surgery, and the variable need for transfusions. Intraoperative autotransfusion is contraindicated in these patients. Our own studies on the presence of tumor cells in the blood shed from the surgical field during oncologic surgery confirm the concerns about a systemic spread of tumor cells after retransfusion. Further efforts aim to an elimination of contaminating tumor cells. In contrast to the literature filters for white blood cell depletion were found to fail to completely remove tumor cells. A 3 log10 retention was measured. Proliferative activity of tumor cells was completely abolished by irradiation of the blood. CONCLUSIONS: Irradiation with 50 Gy allows safe retransfusion of blood salvaged during tumor surgery. This promising possibility is now to be tested in clinical studies.

Blood Loss, Surgical↗
PubMed1982

Effects of antiarrhythmic surgery on late ventricular potentials recorded by precordial signal averaging in patients with ventricular tachycardia.

In seven patients with documented ventricular tachycardia (VT) and prior myocardial infarction, late potentials (LP) were recorded at the end of or after the QRS complex from the body surface using high-gain amplification and the signal averaging technique (RC filter settings 100 to 300 Hz). In 6 to 7 patients VT could be initiated by programmed right ventricular stimulation; in one case, VT was inducible only from the left ventricle during surgery. Surgery was guided by epi- and endocardial mapping. In most cases besides resection of scar tissue, a partial or complete subendocardial encircling ventriculotomy was performed. Postoperatively, LPs were abolished in five cases, VT being no longer inducible. In the remaining two patients, LPs were still present. VT was still inducible in one of these two cases whereas in the other case, no programmed testing was done postoperatively. These data suggest that the abolition of LPs by surgery is closely related to the disappearance of the propensity to stimulus-induced VT. Thus, the averaging technique represents a new approach to the noninvasive control of the efficacy of surgery in patients with VT and prior myocardial infarction.

Adult↗
PubMed1977

Laser application to the angle structures in rabbits, cats, and in human glaucomatous eyes.

Argon laser lesions were induced to the structures of the anterior chamber angle in rabbits and cats and in a pre-enucleated infant's eye. Histopathological changes at different follow-up periods were analyzed. The argon laser beam was also applied to 28 uncontrolled glaucomatous eyes. Twenty-five eyes responded by an abrupt hypotensive effect, but in 21 of them, elevated pressure recurred after 20 to 40 days. Eight eyes maintained low intraocular pressure throughout the 12 to 20 month follow-up period. Of these, 3 were eyes of babies with congenital glaucoma, and 3 had simple glaucoma following an unsuccessful filtering operation. Seven eyes were medically controlled postoperatively and 13 eyes were failures which had to undergo further surgery.

Adult↗
PubMed2002

[Final clinical indications and etiology in 1,023 enucleations. Descriptive databank evaluation with SPSS software in variable response mode with dummy variables].

BACKGROUND: A new data bank developed for ophthalmopathology using a computer-generated, multidigital data code is expected to be able to accomplish complex clinicopathologic correlations of diagnoses and signs, as provided by (multiple) clinical events and histopathologically proven etiologies, and to facilitate the documentation of new data. PATIENTS AND METHODS: In the ophthalmopathology laboratory 2890 eyes were examined between January 20, 1975 and December 12, 1996. The main diagnoses and patient data from this 22-year period were recorded. To facilitate the presentation of data, a 10-year period with eyes of 976 patients enucleated from December, 1986 to December, 1996 was chosen. Principal and secondary diagnoses served for establishing the data bank. The frequencies of successive histologic and clinical diagnoses were evaluated by a descriptive computing program using an SPSS-multi-response mode with dummy variables and a categorical variable listing of the software (SPSS version 10.0) classified as (a) non-filtered random, (b) filtered by multiple etiologies, and (c) filtered by multiple events. RESULTS: The principal groups (e.g., histologic diagnoses concerning etiology) and subgroups (e.g., trauma, neoplasia, surgery, systemic diseases, and inflammations) were defined and correlated with 798 separate diagnoses. From 11 diagnoses/events ascribed to the clinical cases, 11,198 namings resulted. CONCLUSIONS: Thus, a comparative study of complex etiologies and events leading to enucleation in different hospitals of a specific area may be performed using this electronic ophthalmopathologic data bank system. The complexity of rare disease and integration into a superimposed structure can be managed with this custom-made data bank. A chronologically and demographically oriented consideration of reasons for enucleation is thus feasible.

Causality↗
PubMed2002

Comparing dual-stream and standard cardiopulmonary bypass in pigs.

BACKGROUND: Dual-stream (DS) and standard cardiopulmonary bypass (CPB) were compared. METHODS: A DS catheter inserted into the distal ascending aorta across the arch pumps blood through an upper lumen (maximum 2.25 L/min) directed by a bloodstreaming baffle toward the arch vessels. A separate lower lumen pumps blood (maximum 3.75 L/min) into the aorta caudad to the inflated baffle. The baffle is flat and horizontal along the catheter. When the baffle is collapsed the heart or both lumens may perfuse all organs. For 30 minutes 8 randomized CPB pigs had corporeal cooling to 32 degrees C and for 30 minutes had rewarming to 36 degrees C. Eight randomized DS pigs had 25 degrees C upper lumen cooling for 60 minutes. Lower lumen blood flow was streamed at 32 degrees C for 30 minutes, then rewarmed to 36 degrees C for 30 minutes. RESULTS: The change in relative lower lumen to brain blood flow as determined by brain-counted microspheres (15 micron) injected into the ascending aorta was less for DS brains than controls during full flow (DS 63.4+/-129.5 versus CPB 2,585.4+/-250.8, p < 0.001), and when injected into the ejecting-heart left atrium just after weaning off only lower lumen blood flow (DS 250.8+/-297.3 versus CPB 1,159.1+/-782.3, p < 0.001). DS brain temperatures were lower at an equal pump-off core temperature of 36 degrees C+/-0.5 degrees C (DS 31.6 degrees C+/-3.2 degrees C versus CPB 36.5 degrees C+/-1.7 degrees C, p < 0.025). Jugular O2 saturations were not different. CONCLUSIONS: DS-CPB prioritizes pump-filtered separate cold blood flow to the brain over a blood-streaming baffle to wash away potentially surgery related air and particulate matter arising from the heart or ascending aorta.

Animals↗
PubMed1998

Common applications of electrophysiology (EEG) in the past and today: the technologist's view.

The field of electroencephalography (EEG) has witnessed a dramatic development during the last decade. The electroencephalogram that had been principally used as a 'post-hoc' diagnostic procedure is now fully used as an 'on-line' monitor of neural function with its excellent temporal resolution. Neurophysiological monitoring in the operating room, neurological intensive care unit (ICU) and during endovascular procedures allows early identification of impending neurological deficits before irreversible neurological impairment. Long-term monitoring of scalp and synchronized video-EEG recordings and invasive (depth and subdural) electrode studies are well-established tools in the localization of the epileptogenic region for identification of potential candidates for surgery. The advent of digital EEG with digital storage and the ability to manipulate data with digital reformatting, filter and sensitivity changes has allowed us to maximize the information and reduce artifacts. These changes have revolutionized the way in which EEG is performed and interpreted.

Animals↗
PubMed2006

Relation between bitter taste sensitivity and incidence or intensity of propofol injection pain.

BACKGROUND AND OBJECTIVE: In human beings, pain and taste perception are two major sensory inputs. We investigated whether increasing bitter taste sensitivity would increase intensity or incidence of pain associated with propofol, and whether there is a relationship between bitter sensitivity and venepuncture pain. METHODS: One hundred (50 males, 50 females) American Society of Anesthesiologists Grade I adults undergoing elective surgery were included in this study. Determination of the taste thresholds employed a series of propylthiouracil solutions. The filter paper disk method was used to measure the taste threshold. A 20-G intravenous (i.v.) cannula was inserted in the dorsum of the non-dominant hand. Venepuncture pain was assessed by using a numerical rating scale (NRS; 0, no pain and 10, extreme pain). Propofol 10 mL (100 mg) was injected over 30 s. Assessment of pain with i.v. propofol was made using a 4-point scale: 0, no pain; 1, mild pain; 2, moderate pain; 3, severe pain. RESULTS: The NRS score of venepuncture pain was 2.8 +/- 1.5. Sixty patients had pain during propofol injection. There was statistically significant correlation between bitter sensitivity and propofol injection pain, and between bitter sensitivity and venepuncture pain (P < 0.05). CONCLUSIONS: We conclude that increased bitter taste sensitivity correlates with increased intensity or incidence of propofol injection pain and NRS of venepuncture pain.

Adult↗
PubMed1998

Leucocyte filtration during cardiopulmonary bypass hardly changed leucocyte counts and did not influence myeloperoxidase, complement, cytokines or platelets.

In some patients, coronary artery bypass surgery induces postoperative organ dysfunction despite an apparently adequate revascularization and good haemodynamic performance. This complication may be caused by activation of the body's inflammatory systems on blood contact with large foreign surfaces in the extracorporeal circuit. Activated leucocytes may play an important role in organ damage, and it is conceivable that leucocyte removal by filtration may decrease the potential side-effects of cardiopulmonary bypass (CPB). The aim of the present study was to investigate possible effects of leucocyte filtration during the whole CPB period in elective coronary artery bypass surgery on biochemical and clinical parameters. Forty patients were randomized to extracorporeal circulation using a leucocyte-depleting filter (group L, n = 20) or to extracorporeal circulation with no leucocyte filter (group C, n = 20). In the leucocyte-depleted group, the mean total white blood cell counts increased from 6.3 (95% confidence interval, 5.5-7.0) x 10(9)/l to 7.0 (5.7-8.3) x 10(9)/l during extracorporeal circulation and in the control group from 6.3 (5.2-7.3) x 10(9)/l to 8.5 (7.2-9.8) x 10(9)/l. The intergroup difference was not statistically significant (p = 0.84). A substantial increase in concentrations of interleukin-6, myeloperoxidase and complement activation products were observed in both groups without statistically significant intergroup differences. It is concluded that the leucocyte-depletion filter did not cause a significant reduction of circulating white blood cells during CPB, and there were no significant differences between the groups with respect to the inflammatory markers studied.

Aged↗
PubMed1983

Altered intestinal permeability to low-molecular-weight polyethyleneglycols (PEG 400) in patients with Crohn's disease.

The passive intestinal permeability to different-sized low-molecular weight polyethyleneglycols (PEG 400) was studied in 24 patients with Crohn's disease, which were compared to 24 healthy persons. The recovery in 6-hour urine after oral intake was significantly lower (p less than 0.0005-0.005) in the subjects with Crohn's disease for molecules ranging between 282 and 546 in molecular weight. Mathematical modelling of the filtering properties demonstrated a lower filtering efficiency of the larger polyethyleneglycols in the patients than in the healthy individuals. The coefficient of variation for the different polymers was larger in the group of Crohn's disease patients, indicating greater heterogeneity in the intestinal filtering efficiency. In two patients the intestinal uptake of the probe molecules was increased 6 weeks after resectional surgery compared to the uptake before operation.

Adolescent↗
PubMed2000

Developments in robotic cardiac surgery.

A new generation of surgical telemanipulation systems has helped to overcome the limitations of conventional endoscopic tools. These computer-enhanced instrumentation systems provide tremor filtering and motion scaling and allow dexterous manipulations in confined spaces through ports or trocars. Using these systems, total endoscopic coronary artery bypass grafting both on the arrested and on the beating heart has been performed successfully. Repair of mitral valves as well as atrial septal defects has also been performed remotely through 1 centimeter incisions. Despite some early procedural success, operating times are prolonged and a number of conversions have been reported. Currently, the use of telemanipulation systems is restricted to selected patients and limited to very few indications. Further refinements in telemanipulator technology as well as integration of image-based navigation systems may expand the use of computer-enhanced instrumentation systems in the near future.

Cardiac Surgical Procedures↗
PubMed1984

[Postoperative infectious risk in traumatic bone surgery and protocol for antibiotic therapy].

Eleven hundred and sixty eight traumatic cases have been operated on under constant conditions in a conventional operating room with filtered air and positive pressure using absolute filters of 99.999 efficiency. Two hundred and five were submitted to post-operative prophylactic administration of Cephalosporin (Cefazolin) for 2 days. The overall results showed 0.6 p. 100 of infection but 4 cases of severe sepsis were seen in the group of patients who had received prophylactic antibiotics. The authors have compared these results with those obtained during the previous period when the operating room was less modern. They conclude that this factor is of paramount importance. On the other hand, they have observed 2.1 p. 100 of contaminated drains without subsequent infection. They are concerned at the increase of gram-negative organisms resistant to Cefazolin (60 p. 100) and of Staphylococci resistant to Methicillin (30 p. 100). They conclude that the peroperative flash technique of the administration of Penicillin M is worthwhile.

Aged↗
PubMed2005

Nonpenetrating glaucoma surgery.

Nonpenetrating glaucoma surgery continues to evolve and improve. New technical refinements and increased experience among its practitioners have led to improved efficacy and longer duration of filter survival. These refinements include the use of intraoperative and postoperative antimetabolites, adjunctive space-maintaining devices, and postoperative yttrium-aluminum-garnet laser goniopuncture. Deep sclerectomy and viscocanalostomy vary significantly in their surgical approaches and mechanisms of aqueous outflow. An understanding of the microanatomy of the aqueous outflow structures is necessary to gain surgical access to Schlemm's canal and to augment aqueous outflow surgically through the trabecular meshwork. Indications and contraindications for nonpenetrating glaucoma surgery are discussed.

Glaucoma↗
PubMed1999

Initial trabeculectomy with intraoperative mitomycin-C application in primary glaucomas.

PURPOSE: This is a prospective randomized study designed to compare the overall efficacy of intraoperative application of mitomycin-C (MMC) in eyes with no previous ocular surgery versus standard trabeculectomy without MMC. METHODS: Twenty-five patients with primary glaucoma had been treated with trabeculectomy in one eye and trabeculectomy with MMC in the other eye. Patients were followed up for 18 months. RESULTS: Intraocular pressure (IOP) was 20 mm Hg or less in 23 eyes (92%) in the treatment group after a mean follow up of 17.8 +/- 1.1 months and 17 control eyes (68%) after mean follow up period of 17.8 +/- 1.2 months (range, 16.7-19 months). Wound leaks occurred in 10 (40%) of the treatment group and 3 (12%) of control group. Bleb scarring developed in 1 eye (4%) of the treatment group and 6 (24%) of the control group. Hypotony maculopathy developed in 3 (12%) of the MMC group. Postoperatively, laser suture lysis was needed in 13 (52%) of the treatment group and 21 (84%) of the control group. Additional filter was needed in (4%) of the treatment group, while additional filters were needed in 7 (28%) of the control group. CONCLUSION: Intraoperative MMC application may increase the success rate of glaucoma surgery, but close follow-up and meticulous management of patients are needed, especially in the early postoperative period.

Adult↗
PubMed2001

Pediatric cardiac surgery with cardiopulmonary bypass: pathways contributing to transient systemic immune suppression.

Cardiovascular surgery with cardiopulmonary bypass (CPB) can lead to postoperative complications like postpericardiotomy syndrome (PPS), capillary leak syndrome, or multiple organ failure. In children, PPS morbidity is up to 30%, and intra- and immediate postoperative mortality is up to 4%. For these complications, the CPB is made responsible. Its etiology is not yet clarified in detail, but is thought to be of immunologic origin. The exact knowledge of these reactions is crucial for the selection of treatment strategies. The immune response to CPB surgery in children comprises of a cascade of pro- and anti-inflammatory events. Proinflammatory responses are indicated by the release of interleukin (IL)-6 and IL-8, and the activation of alternative complement pathway. This reaction is mainly a response to surgical trauma and medication and only activation of the alternative complement pathway is CPB specific. Antiinflammatory response during CPB surgery is serologically indicated by the systemic release of the immunosuppressive cytokine IL-10 already before that of proinflammatory cytokines. CPB surgery induces population shifts of the leukocyte subsets, changes their degree of activation, and contributes to the phenotype of a peripheral immune suppression. Circulating neutrophils are selectively filtered and inactivated. T-helper (Th) cells shift transiently to the Th2 phenotype, indicating the prevalence for a humoral immune response. These alterations start immediately after the onset of the CPB. Increased immunosuppression may be involved in PPS development and may be linked to an allergic/atopic predisposition. A generalized model of the immune sequela to pediatric cardiovascular surgery with CPB is drawn. CPB induces a systemic transient anti-inflammatory response by elimination of activated cells, by compensatory reaction to local, systemically not observable, proinflammatory responses, by IL-10 release, by anesthetics and medication, and by leukocyte extravasation. The subsequent proinflammatory reaction is the reaction to surgical trauma modulating the anti-inflammatory reaction. Possible therapeutic consequences of these findings may include treatment strategies that modulate the anti-inflammatory response. More studies are needed to test this hypothesis.

Cardiac Surgical Procedures↗
PubMed1993

Autotransfusion in aortic surgery: the Haemocell System 350 cell saver.

Autotransfusion was performed during elective abdominal aortic reconstruction in ten patients using the recently developed Haemocell System 350. A mean of 60 per cent of total blood loss was salvaged, and during operation each patient was autotransfused 1 unit. Good preservation of cellular components, including platelets, was seen after processing with the device, which uses a vortex mixing filter for cell separation. There was no evidence of coagulopathy; mean free plasma haemoglobin levels were slightly raised (17 mg/dl) and plasma heparin concentration was negligible (0.10 units/ml) 4 h after surgery. A transient drop in plasma fibrinogen levels and the appearance of fibrin degradation products in low concentrations (mean 1.5 mg/l) were seen. Oxyhaemoglobin dissociation curves showed the salvaged red blood cells to have a normal affinity for oxygen. Renal and hepatic function remained unaltered and there were no complications attributable to autotransfusion. The device was easy to handle and a trained operator was not required.

Adult↗
PubMed2004

Leucocyte filtration of residual heart-lung machine blood in children undergoing congenital heart surgery.

Cardiopulmonary bypass (CPB) leads to a generalized inflammatory reaction, resulting in increased postoperative leucocyte counts and decreased pulmonary function. In adults, removal of leucocytes from the residual heart-lung machine blood after CPB improved postoperative oxygenation. In children, however, the clinical effects of leucocyte filtration of the residual heart-lung machine blood are unknown. Therefore, we measured postoperative leucocyte counts and arterial blood oxygenation in children undergoing congenital cardiac surgery in a randomized prospective study. Anaesthesia and CPB were standardized. After CPB, the residual heart-lung machine blood was collected as usual. In a group of 25 children, this blood was filtered with a leucocyte depletion filter before transfusion. A control group of 25 children received this blood unfiltered. We found that the postoperative leucocyte counts were significantly lower in the filter group than in the control group (p = 0.02, repeated measurements ANOVA). This difference reached a maximum on the second postoperative day (12.9 x 10(9)/L filter versus 15.9 x 10(9)/L control, p = 0.02, Student's t-test). Values for the arterial blood oxygenation on the first postoperative day were not different between the two groups (15.5 +/- 1 kPa filter versus 14.6 +/- 1.3 kPa control, p = 0.57, Student's t-test). We conclude that leucocyte filtration of the residual heart-lung machine blood reduced systemic leucocyte counts, but did not improve arterial blood oxygenation in children after congenital heart surgery.

Cardiopulmonary Bypass↗
PubMed2006

Hospital Episode Statistics and trends in ophthalmic surgery 1998-2004.

BACKGROUND: Hospital episode statistics (HES) is a UK national database for the National Health Service (NHS), now available online. The purpose of this study was to observe trends in ophthalmic operations performed during the period from 1998 to 2004, using this data. METHODS: From the 'Main Operation' codes within the 'Free data' section of the HES website we analysed data in regard to 28 specific ophthalmic operations. These represented each sub speciality within ophthalmology. RESULTS: The figures show a change in the total number and proportions of operations performed for many of the procedures. For example, there was an increase in numbers of orbital decompressions, but a decrease in numbers of glaucoma filtering operations. Changing trends could be seen in different surgical areas such as the change in operations used for corneal grafting and in retinal surgery. CONCLUSION: The HES database represents an important, potentially useful source of information. There are imitations in interpretation of and validity of such data related to coding inconsistencies. We suggest the benefit of the data comes from observing trends rather than exact numbers. As other studies using this data have suggested, it is important that clinicians are involved in improving the quality of this data.

Cataract Extraction↗
PubMed1995

Continuous non-invasive blood pressure monitoring by brachial artery displacement method in high-risk surgical patients.

Continuous non-invasive blood pressure (CNBP) measurements were compared to invasive radial artery pressure recordings in 26 patients with cardiac, vascular and/or pulmonary disease. Patients were studied during general anaesthesia (n = 6), regional anaesthesia (n = 10), or combined technique (n = 10) for abdominal or transurethral surgery. CNBP was obtained from a cuff placed around the upper arm and simultaneously compared to invasive pressure from the ipsilateral radial artery. A CNBP device (7001 Cortronic) used intermittent oscillometric measurement for calibration. Through a cuff continuously inflated to a pressure of 20 mmHg, a microprocessor-controlled electro-pneumatic acquisition system sensed displacements of the brachial artery wall. Amplified, digitally converted, filtered and transformed data were displayed as a continuous pulse pressure waveform and digital pressure values on the screen. The CNBP method functioned without disturbances before surgery in all patients. Intra-operative use of electrocautery or a spontaneous occurrence of warning on the screen repeatedly triggered oscillometric recalibration, hence CNBP measurements were discontinued in nine patients. Coefficients of correlation (r) of all invasive and CNBP pairs (n = 1111) were 0.68, 0.58 and 0.70 for systolic, diastolic, and mean blood pressures, respectively. Prediction errors (bias, mean +/- SD) were -13.6 +/- 22.5 mmHg (on average CNBP < invasive pressure) for systolic, +13.0 +/- 12.4 mmHg (CNBP > invasive pressure) for diastolic and +5.0 +/- 13.9 mmHg (CNBP > invasive pressure) for mean CNBP, as compared to radial artery pressure values. Absolute errors (precision) were 25.3 +/- 9.4 mmHg for systolic, 17.4 +/- 4.5 mmHg for diastolic, and 13.9 +/- 4.6 mmHg for mean CNBP. During anaesthesia induction (n = 672) the difference between consecutive measurements (trend of pressure changes) with invasive and CNBP method exceeded 20 mmHg in 90 (13.3%) instances for systolic, in 33 (4.9%) instances for diastolic, and in 45 (6.6%) instances for mean blood pressure. In conclusion, the CNBP method by brachial artery wall displacement failed to measure the blood pressure reliably and to display the trend of pressure changes correctly during anaesthesia induction. In its present form this CNBP method should not replace invasive blood pressure monitoring in high-risk patients neither for anaesthesia induction nor during non-thoracic surgical procedures.

Abdomen↗