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PubMed1993

Holmium laser sclerectomy. Success and complications.

PURPOSE: To investigate the safety and efficacy of holmium YAG laser sclerectomy, a new laser filtration procedure. METHODS: The authors performed holmium YAG laser sclerectomy on 49 eyes of 46 patients (mean follow-up, 12.3 +/- 1.1 months). RESULTS: Mean preoperative intraocular pressure (IOP) was 26.9 +/- 1.3 mmHg; postoperative mean IOP on last follow-up visit was 19.7 +/- 1.6 mmHg. Thirty (61%) of 49 eyes achieved a final IOP of 5 to 22 mmHg, 29 (59%) of 49 had a final IOP of 5 to 19 mmHg, and 21 (43%) of 49 had a final IOP of 5 to 15 mmHg. Sixteen (73%) of 22 eyes treated postoperatively with 5-fluorouracil (5-FU) had a final IOP of 21 mmHg or less. Twenty-seven percent of eyes lost one or more lines of vision, and 36% of eyes gained one or more lines of vision; there was no median change in visual acuity. Complications included suprachoroidal hemorrhage in 7 (14%) of 49 eyes and intraoperative vitreous hemorrhage in 2. Seventeen (35%) of 49 eyes required a second IOP-lowering procedure. CONCLUSION: Holmium YAG laser sclerectomy is an effective means to perform glaucoma filtration surgery. This is a full-thickness filtering procedure, with all of the risks attendant.

Aged↗
PubMed2004

Increased syndecan expression following myocardial infarction indicates a role in cardiac remodeling.

The purpose of this study was to identify essential genes involved in myocardial growth and remodeling following myocardial infarction (MI). Left ventricular noninfarcted tissues from six mice subjected to MI under general anesthesia and from six sham-operated mice were obtained 1 wk after primary surgery and analyzed by means of cDNA filter arrays. Out of a total of 1,176 genes, 641 were consistently expressed, twenty-three were upregulated and thirteen downregulated. Five genes were only expressed following MI. Syndecan-3, a transmembranous heparan sulfate proteoglycan, was found to be upregulated together with a transcriptional activator of syndecans, Wilms tumor protein 1 (WT-1). Northern blotting demonstrated a significant upregulation of syndecan-1, -2, -3, and -4, WT-1, fibronectin, and basic fibroblast growth factor (FGF) receptor 1. Furthermore, Western blot analysis showed statistically significant increases in protein levels for syndecan-3 and -4. In conclusion, we have identified a subset of genes with increased expression in noninfarcted left ventricular tissue following MI, including syndecans 1-4, WT-1, fibronectin, collagen 6A, and FGF receptor 1. Since the syndecans link the cytoskeleton to the extracellular matrix and function as required coreceptors for FGF, we suggest a role for the syndecans in cardiac remodeling following MI.

Animals↗
PubMed1996

Does activated neutrophil depletion on bypass by leukocyte filtration reduce myocardial damage? A preliminary report.

An important factor in the production of myocardial damage following cardiopulmonary bypass in the creation of oxygen derived free radicals. Few sources for these radicals have been identified but experimentally activated neutrophils are known to release free radical which contribute to myocyte necrosis. The aim of this pilot study was to identify whether, by depleting patients of leukocytes and particularly neutrophils on bypass, a better degree of myocardial protection could be observed using specific identifiers of myocardial damage. Ten patients undergoing urgent coronary artery bypass for unstable angina with impaired left ventricular function were leuko-depleted using a PALL medical leukocyte filter in the extra corporeal circulation together with leukocyte depletion of all transfused blood. A similar group of matched controls had only an arterial line filter without leukodepletion. All patients were operated by one surgeon using identical techniques of intermittent cross clamping and fibrillation at moderate hypothermia. Full blood count, Glutathione, Troponin T and CPK/MB were measured before, during and at identified intervals up to 72 hour after bypass. Preliminary results show little change in the total leukocyte count but the Troponin T and CPK/MB values were lower in the filtered group than in the control group and an increased level of total Glutathione in the filter group showed that there was less oxidated stress on the myocardium. Currently this filter is an expensive addition to bypass surgery but these preliminary results suggest that activated neutrophil depletion on bypass may be of benefit to patients with unstable angina, impending myocardial necrosis and low ejection fraction.

Aged↗
PubMedDate not supplied

[Functional outcome of advanced chronic glaucoma after trabeculectomy].

We studied the risk of sudden loss of visual fields after trabeculectomy on 17 eyes with primary open angle glaucoma and small residual visual fields. We think that it is possible to try to these patients filtering procedures with precautions before and during surgery.

Aged↗
PubMed2006

Postoperative application of mitomycin c improves the complete success rate of primary trabeculectomy: a prospective, randomized trial.

BACKGROUND: The intraoperative application of mitomycin c for primary trabeculectomy is associated with potentially sight-threatening side-effects. This study was performed to evaluate the pressure-lowering effect of postoperative application of mitomycin c for primary trabeculectomy and to evaluate the complications of this new technique. MATERIALS AND METHODS: A randomized, prospective clinical trial with 52 consecutive patients scheduled for glaucoma surgery in one large surgical center was performed. Patients underwent routine trabeculectomy. In group 1, mitomycin c (0.05 mg/ml) was applied topically to the filtering bleb for 5 min on the 3 days after surgery (postoperative application). In group 2, no mitomycin c was applied (controls). The IOP values, visual acuity, number of antiglaucomatous medications and complications were evaluated. RESULTS: Follow-up was evaluated up to 24 months for all patients. The mean intraocular pressure decreased from 31.1 to 15.4 mmHg in group 1 and from 24.8 to 15.6 mmHg in group 2 (P=0.79; t-test). The average number of medications decreased from 2.5 and 2.4 to 0.4 and 0.6 (P=0.53; t-test) in groups 1 and 2, respectively. No cases of hypotony maculopathy occurred. An individual decrease of more than 25% of the IOP was present in 84.6% in group 1 and in 53.8% in group 2 (P<0.017). Survival analysis for eyes with a complete surgical success revealed a better outcome of eyes in group 1 as compared to the eyes in group 2 (P<0.013; log-rank test). CONCLUSIONS: To our knowledge, this is the first prospective, randomized clinical trial to evaluate the efficacy of postoperative mitomycin c application in primary trabeculectomy. The application of mitomycin significantly reduced the IOP while not increasing the rate of complications.

Adult↗
PubMed1998

[Trabeculotomy, deep sclerectomy and viscocanalostomy. Non-fistulating microsurgical glaucoma operation ab externo].

Filtering procedures have been the gold standard in glaucoma surgery for more than 30 years. Trabeculotomy, deep sclerectomy, and viscocanalostomy might become the procedures of first choice in the future. These new, non-penetrating procedures have not yet been compared to filtering procedures in prospective randomized studies with long-term follow-up. In addition, it is not really known how they modify outflow of the aqueous humor. The surgical technique is described and the most likely underlying effects are discussed.

Adult↗
PubMed1998

Randomized trial comparing packed red cell blood transfusion with and without leukocyte depletion for gastrointestinal surgery.

BACKGROUND: Allogeneic transfusion is associated with postoperative infections that significantly prolong hospital stays and increase costs. Recent studies suggest that filtering leukocytes from blood prior to transfusion reduces the risk of postoperative infection associated with blood transfusion. We compared the incidence of postoperative infections, hospital stays, and hospital charges of gastrointestinal surgery patients transfused with packed red cells or leukocyte-depleted cells. METHODS: Consecutive patients admitted for elective gastrointestinal surgery without previous blood transfusion were randomized to receive routine packed red cells or packed red cells filtered to remove leukocytes if transfusion was required. Multivariate analysis was used to assess the significance of the relationship between leukocyte-depleted blood and postoperative infectious complications, postoperative stay, and hospital charges. RESULTS: Fifty-nine (27%) of the 221 patients were transfused. The most significant variable related to transfusion was intraoperative blood loss (P <0.0001), followed by admission hematocrit (P <0.0001) and age (P = 0.0022). Infections were noted in 16% of the patients: 11% of untransfused patients, 16% of leukocyte-depleted blood recipients, and 44% of patients transfused with packed red cells. Both operative site and nosocomial infections were significantly (P <0.001) more frequent in patients transfused with packed red cells compared with patients transfused with leukocyte-depleted red cells. Postoperative stays averaged 9 days for untransfused patients, 12 days for leukocyte-depleted recipients, and 18 days for recipients of packed red cells. Hospital charges were $19,132, $33,954, and $41,002, respectively. Both transfusion and infection were significantly (P <0.001) related to postoperative stay in multivariate analysis. Hospital charges were significantly related to postoperative stay (P <0.001), blood loss (P <0.001), age (P <0.001), infection (P = 0.007), and randomization to packed red cells (P = 0.032). CONCLUSIONS: Filtering blood of leukocytes prior to transfusion for elective gastrointestinal surgery is associated with lower risk of postoperative infection, shorter postoperative stays, and lower hospital charges.

Cost-Benefit Analysis↗
PubMed1998

Epiretinal membranes surrounding idiopathic macular holes.

PURPOSE: To describe the features of the epiretinal membranes (ERMs) surrounding idiopathic macular holes. METHODS: The charts of 83 consecutive patients (85 eyes) who underwent macular hole surgery with a systematic search for an ERM around the hole were reviewed. Visual acuity testing, fundus biomicroscopy, red free and blue filter fundus photographs, and fluorescein angiograms were performed before and after surgery. Eyes with and without ERM removal were compared. RESULTS: An ERM was removed from 26 of 85 eyes (30.6%). ERMs were found more frequently in stage 4 than in stage 3 macular holes (76.9% versus 24.6%; P < 0.01). Holes had been present for longer in eyes with ERM than in those without (14.7 versus 8.6 months; P = 0.05). Fewer stage 3 holes with an ERM had an operculum than those without (P = 0.01). The outcome and complication rates were similar in eyes with an ERM and those without. Of the 24 ERMs detectable on blue filter fundus photographs, only 11 (45.6%) were visible on red free photographs. CONCLUSION: We support the hypothesis that the presence of ERMs surrounding idiopathic macular holes is secondary to hole formation.

Aged↗
PubMed2000

Surgical repair of leaking filtering blebs.

PURPOSE: To report the surgical management of leaking filtering blebs occurring after blebitis or persistent hypotony. DESIGN: Retrospective, noncomparative case series. PARTICIPANTS: Twenty-two eyes of 20 patients with late bleb leak, blebitis or endophthalmitis, hypotony maculopathy, or bleb dysesthesia on presentation to the glaucoma service who required surgical bleb revision from 1990 through 1999. INTERVENTION: Pedicle flap, partial excision, and advancement or free conjunctival autologous graft techniques for surgical bleb revision. Type of bleb revision was dependent on the dimensions of the bleb and quality of surrounding conjunctiva. MAIN OUTCOME MEASURES: Preoperative and postoperative intraocular pressure (IOP), status of bleb leak, reoperation for glaucoma, or requirement for postrevision glaucoma medical therapy, with success defined as the need for two or fewer glaucoma medications after revision. RESULTS: Eighty-six percent (19/22) of eyes that underwent surgical bleb revision had resolution of leak and IOP control using two or fewer medications after one or more bleb revisions. The preoperative IOP (mean +/- standard deviation) was 3.7 +/- 2.6 mmHg (range, 0-8 mmHg). After an average follow-up of 21 months (range, 8-108 months), the IOP was 11.0 +/- 4.4 mmHg for patients taking 0.6 +/- 1.0 glaucoma medications. Eighteen percent (4/22) of eyes required two or more bleb revisions. In one eye, an IOP spike of 36 mmHg developed after revision, which required laser suture lysis on two occasions before the IOP was significantly lowered. The three failures were: one eye that required three or more medications for IOP control, a patient whose eye had a persistent leak after revision and who was not mentally competent to undergo repeat revision, and one eye that required combined glaucoma and cataract surgery after revision. CONCLUSIONS: Surgical bleb revision has a high success rate of closing late bleb leaks, maintaining glaucoma control, and preserving vision, with few postoperative complications. The appropriate surgical procedure for revision must be based on the individual clinical situation and can result in successful bleb revision.

Adult↗
PubMed2000

Endoillumination during vitrectomy and phototoxicity thresholds.

AIM: To assess the retinal phototoxicity hazards of and to provide safety margins for endoillumination during vitrectomy. METHODS: The absolute power and spectral distribution from various light sources and filter combinations that are commercially available for vitreous surgery were measured. The maximal exposure times based on the ICNIRP safety guidelines for photochemical and thermal injury of the aphakic eye were calculated. Additionally, the effect of various measures that reduce the risk of phototoxicity was evaluated. RESULTS: Measurements of the spectrum and energy indicated that the ICNIRP safety guidelines for photochemical retinal damage are exceeded within 1 minute for nine out of 10 combinations tested. With an additional 475 nm long pass filter, light levels below 10 mW, and a distance from light probe to retina of at least 10 mm, the allowable exposure time can be increased up to 13 minutes. Thermal damage can be anticipated when the light probe touches the retina. CONCLUSION: Commercially available light sources for endoillumination during vitrectomy are not safe with respect to photochemical retinal damage. Even with maximal precautions macular phototoxic damage remains a factual danger during vitrectomy.

Hot Temperature↗
PubMed1992

Postoperative infection and natural killer cell function following blood transfusion in patients undergoing elective colorectal surgery.

The frequency of infection in 197 patients undergoing elective colorectal surgery and having either no blood transfusion, transfusion with whole blood, or filtered blood free from leucocytes and platelets was investigated in a prospective randomized trial. Natural killer cell function was measured before operation and 3, 7 and 30 days after surgery in 60 consecutive patients. Of the patients 104 required blood transfusion; 48 received filtered blood and 56 underwent whole blood transfusion. Postoperative infections developed in 13 patients transfused with whole blood (23 per cent, 95 per cent confidence interval 13-32 per cent), in one patient transfused with blood free from leucocytes and platelets (2 per cent, 95 per cent confidence interval 0.05-11 per cent) and in two non-transfused patients (2 per cent, 95 per cent confidence interval 0.3-8 per cent) (P less than 0.01). Natural killer cell function was significantly (P less than 0.001) impaired up to 30 days after surgery in patients transfused with whole blood. These data provide a strong case against the use of whole blood transfusion in patients undergoing elective colorectal surgery.

Adult↗
PubMed2005

Liver transplantation with simultaneous removal of an intracardiac transjugular intrahepatic portosystemic shunt and a vena cava filter without the utilization of cardiopulmonary bypass.

Transjugular intrahepatic shunts (TIPSs) are widely used in the management of portal hypertension complications including variceal bleeding, refractory ascites, and hepatic hydrothorax. Vena cava filters (VCFs) are an important therapeutic modality in the prevention of pulmonary emboli in patients suffering deep venous thrombosis and clinical contraindications for anticoagulation. Stent and filter misplacement or migration may occur, complicating liver transplantation (LT) surgery. We describe the intraoperative management of a patient with cirrhosis, who had a TIPS extending into the right atrium (RA) and a retrohepatic VCF. Stent and filter removals were deferred until the time of LT. Both procedures were performed successfully by complete cava and portal reconstruction. In conclusion, careful assessment and surgical management of patients with stent and filters permits successful LT.

Adult↗
PubMed2005

Total leukocyte control for elective coronary bypass surgery does not improve short-term outcome.

BACKGROUND: Despite early promise as a means of reducing the inflammatory response to surgery and subsequent organ damage, the evidence of the clinical value of leukocyte filtration remains equivocal. METHODS: Three hundred patients presenting for routine coronary artery bypass surgery were randomized to a total leukocyte filtration group (filters in five different locations) and a control group with a standard 40-mum filter in the bypass return line only. Data on efficacy and safety of leukocyte filtration were collected by research and postoperative care staff who were blinded to the mode of filtration. RESULTS: Leukofiltration achieved a transient fall in white cells immediately after surgery (p = 0.07) and a sustained fall in platelets, which was still significant on the second postoperative day (p = 0.0001). However, there were no significant differences in postoperative hospital stay, the primary outcome variable (p = 0.35), in ICU stay (p = 0.92), or mortality (p = 1.0). There were no differences in postoperative cardiac status including cardiac output (p = 0.16), inotrope (p = 0.93) or balloon pump (p = 0.48) requirement, or 24-hour troponin (p = 0.60). Similarly there were no differences in pulmonary or renal function (intubation time (p = 0.83), respiratory index (p = 0.19) rise in creatinine (p = 0.13) or hemofiltration (1.0)). Leukofitration was not associated with a statistically significant increase in bleeding or requirement for blood or blood products. It was associated with a decrease approaching significance (p = 0.1) in number and severity of postoperative wound infections. Three filters were blocked during use but were changed without incident or compromise to patient safety. CONCLUSIONS: Leukocyte filtration is safe but not efficacious in improving short-term outcome.

Aged↗
PubMed2001

Mercury vapour release from a dental aspirator.

OBJECTIVE: To investigate the release of mercury vapour from a dental aspirator which vented its waste air through its base directly into the surgery environment. METHODOLOGY: Mercury vapour in air concentrations were measured at the breathing zone of the dentist during continuous operation of the aspirator. Further series of mercury vapour measurements taken at the aspirator exhaust vent were carried out to determine the sources of mercury vapour from this particular device. RESULTS: At the dentist's breathing zone, mercury vapour concentrations of ten times the current occupational exposure limit of 25 micrograms/m3 were recorded after 20 minutes of continuous aspirator operation. A build up of amalgam contamination within the internal corrugated tubing of the aspirator was found to be the main source of mercury vapour emissions followed by particulate amalgam trapped within the vacuum motor. As the vacuum motor heated up with run time, mercury vapour emissions increased. It was found that the bacterial air exhaust filter (designed to clean the contaminated waste air entering the surgery) offered no protection to mercury vapour. In this case the filter trapped particulate amalgam which contributed to further mercury vapour contamination as high volume air was vented through it. CONCLUSION: It is not known how many dental aspirators are in use that vent their waste air directly into the surgery or if this aspirator is representative of others in existence. The safety of dental aspirating systems with regard to mercury vapour exposure requires further investigation.

Air Pollution, Indoor↗
PubMed2001

A randomized, controlled, clinical trial of a chemically-reactive heated humidifier.

BACKGROUND: Inspired gases can be warmed and humidified in a variety of ways. The effect of a chemically-reactive heated heat and moisture exchanger/hygroscopic condenser humidifier (HME/HCH) on secretions, rate of core body warming, blood loss, and time to extubation was studied in hypothermic post-cardiac surgery patients. METHODS: Fifty patients with normal ventricular function, undergoing coronary bypass grafting, were randomized to receive either a conventional HME (Gibeck, Humid-Vent 1 [PN 11112], Hudson RCI, Temecula, California) or a chemically-heated HME (Thermax HCH Filter [PN 9302], Enternet Medical, Las Vegas, Nevada) following surgery or on arrival in the ICU. Effects on secretions, core temperature, postoperative bleeding, duration of intubation, and added resistance were measured. The Thermax weighs 67 g and adds 79 mL of dead space. The Humid-Vent 1 weighs 9.4 g and adds 10 mL of dead space. RESULTS: There was no significant difference between the 2 devices in time to extubation, blood loss, or quality or quantity of secretions. Use of the Thermax device, however, resulted in a more rapid rise in body temperature (0.299 degrees C/h with the Thermax vs 0.073 degrees C/h with the Humid-Vent 1, p = 0.001) and more added resistance (0.0672 cm H(2)O/L/s with the Thermax vs 0.0123 cm H(2)O/L/s with the Humid-Vent 1, p = 0.00000172). CONCLUSIONS: The Thermax chemically-heated HME results in more rapid warming of mildly hypothermic patients following cardiopulmonary bypass than does a conventional passive HME.

Airway Resistance↗
PubMed2000

[Use of temporal vena cava filter in a patient with a high risk of perioperative pulmonary embolism].

Intraluminal caval filter placement can be applied in order to prevent pulmonary embolism. When surgery has to be performed in the patient with proximal deep venous thrombosis anticoagulant therapy should be reduced and filter placement is indicated. Temporary filter appears an interesting option, as it can be removed shortly after surgical intervention, when contraindications to anticoagulation no longer exist. However, obligatory removal of a temporary device in case of suspected filter or vena cava thrombosis emerges as a new clinical problem. We present a ease of 20 year old woman with proximal deep venous thrombosis and high risk of pulmonary embolism in whom temporary vena caval filter with heparin infusion were chosen as a method of perioperative pulmonary embolism prevention.

Adult↗
PubMed1999

Greater increase in cytokine concentration after salvage with filtered whole blood than with washed red cells, but no difference in postoperative hemoglobin recovery.

BACKGROUND: Inflammatory mediators are released in association with intraoperative and postoperative salvage of blood. Whether these mediators (cytokines) participate in the modulation of erythropoiesis or not has been investigated. STUDY DESIGN AND METHODS: Twenty-seven patients who were to undergo total knee replacement surgery were randomly assigned to postoperative blood salvage with either filtered whole blood or washed red cells. Patients with postoperative blood loss <400 mL were considered a control group. The control group did not receive any transfusions. Plasma concentrations of the anaphylatoxin C3a, the C5b-9 terminal complement complex, and the cytokines interleukins 6 and 8, hemoglobin, reticulocytes, and red cell volume fraction in the patients were repeatedly analyzed before and after surgery. RESULTS: Significantly increased concentrations of interleukin 6 appeared in all three groups, which was interpreted as a response to the surgical trauma. The increase was significantly greater in the group that received filtered whole blood after return of shed blood. The recovery of hemoglobin levels did not differ in the groups. CONCLUSION: The transfusion of filtered whole blood leads to the formation of interleukin 6 in the circulation, but postoperative hemoglobin recovery was similar in all groups.

Aged↗
PubMed1998

Rheological properties and function of blood cells in stored bank blood and salvaged blood.

The technique involving filtration of diluted blood enables the separate analysis of the flow properties of different cell subpopulations. This study was designed to assess the changes occurring in the flow properties and function of blood cells in stored bank blood and salvaged blood compared to patient blood in a given clinical situation. We measured hydrogen peroxide production by neutrophils and the filterability, through 5 microm Nucleopore filters, of isolated red blood cells and of diluted blood. Samples were obtained from patients undergoing aortic surgery and blood intended for transfusion: either salvaged during surgery or stored bank blood. Both salvaged and bank blood were much less filterable than patient blood, with reduced deformability of both red and white blood cells. However, salvaged blood contained highly activated neutrophils with a prolonged transit time of the 'fast-flowing' cells in the analysis compared to bank blood. Bank blood contained significantly more particles which acted as pore-blockers. Cells in bank and salvaged blood therefore have markedly abnormal flow and biochemical properties compared to patient blood.

Blood Banks↗