Bronchial obstruction due to a tumor embolus of the contralateral lung during pneumonectomy is an uncommon and fatal complication. According to previous cases, a bronchial balloon of double-lumen endotracheal tube (DLT) could prevent a dislodged tumor from traveling to the contralateral lung. We experienced a tumor embolism from the bronchus with cancer to the other bronchus despite applying DLT. A 59-year-old male with endobronchial lung cancer underwent a left pneumonectomy. One-lung ventilation was established by the right-sided DLT. After a left bronchial division, a sudden increase of peak airway pressure and reduction of the expired tidal volume to 50 ml was observed. Intraoperative fiberoptic bronchoscopy showed a near total obstruction of the right main bronchus due to tumor emboli. It was not possible to remove the tumor embolus through bronchoscopic suction and forceps. Therefore, we reopened the left bronchial stump and successfully extracted tumor embolus under bronchoscopic guidance.
Airway obstruction; Bronchial neoplasm; Pneumonectomy; Double-lumen endotracheal tube
Thrombolytic drugs are widely used for the management of cerebral venous sinus thrombosis patients. Several in vitro models have been developed to study clot lytic activity of thrombolytic drugs, but all of these have certain limitations. There is need of an appropriate model to check the clot lytic efficacy of thrombolytic drugs. In the present study, an attempt has been made to design and develop a new model system to study clot lysis in a simplified and easy way using a thrombolytic drug, streptokinase.
Whole blood from healthy individuals (n = 20) was allowed to form clots in a pre-weighed sterile microcentrifuge tubes; serum was removed and clot was weighed. After lysis by streptokinase fluid was removed and remnants of clot were again weighed along with the tube. Percentage of Clot lysis was calculated on the basis of the weight difference of microcentrifuge tubes obtained before and after clot lysis.
There was a significant percentage of clot lysis observed when streptokinase was used. On the other hand with water (negative control), minimal (2.5%) clot lysis was observed. There was a significant difference between clot lysis done by streptokinase and water.
Our study could be a rapid and effective methodology to study clot-lytic effect of newly developed drugs as well as known drugs.
The Model 6120 ball valve prosthesis introduced in 1965 is still strongly supported as a mitral valve substitute in many centers around the world. A current reassessment of the performance of this prosthesis is therefore pertinent to current medical practice.
In this institution since 1974, 227 Starr-Edwards caged ball valves have been implanted in the mitral position during isolated valve replacement. Two models of caged ball valves were used concurrently: the silastic ball valve in 108 patients (48%) and the composite strut “tract” valve in 119 (52%).
Hospital mortality was 7%, and 8-year survival (standard error) was 74 (6%), with 100% follow-up, documenting 752 total patient-years. No late deaths were known to be valve related, and there were no cases of prosthetic thrombosis. The actuarial estimate of patients free from thromboembolism at 8 years was 89 (4%) with a linearized rate of 1.3% per year. At the most recent follow-up, 95% of the patients were in the New York Heart Association (NYHA) Classes I or II. These good results were partly due to an awareness at operation of ventricular outflow tract size requirements and to strict control of postoperative anticoagulation.
We conclude that the Starr-Edwards ball valve is the mitral valve of choice in the young patient who is able to take anticoagulation drugs and has a left ventricular outflow tract of satisfactory size.
A disc valve of new design was used successfully for the replacement of the mitral valve in patients with rheumatic mitral valve disease. This valve would appear to have the following advantages over the mitral ball valve prosthesis:
• Lower left atrial pressure after replacement.
• Elimination of the hazard of left ventricular outflow tract obstruction with mitral valve replacement.
• Decreased incidence of thromboembolization.
• Abolition of possibility of ventricular septal irritation.
Despite the better outlook for this valve compared with the ball valve for mitral valve substitution, the mitral valve should always be repaired whenever feasible. Repair is possible in the majority of patients.
Endobronchial blood clot is an unusual cause of airway obstruction leading to lung collapse in the postoperative period. It is not always easy to pin point the exact etiology in the presence of multiple risk factors. Pulmonary collapse can herald the onset of severe haemodynamic derangements and hypoxemia. So, early identification and management is crucial for preventing catastrophic complications. Various modalities have been described in the literature for removing the obstructing clot and re-expansion of the lung.
We present a case of postoperative left lung collapse by an obstructing endobronchial blood clot in a patient undergoing coronary artery bypass graft surgery.
Endobronchial blood clot; Pulmonary collapse; Bronchoscopy
One of the most serious adverse events associated with anterior cervical spine surgery is wound hematoma resulting in airway compromise. The reported incidence of this postoperative complication has varied from 0.2% to 1.9%. Obstruction of the airway secondary to bleeding presents a challenging clinical scenario given the rapidity of onset, distorted anatomy of the upper respiratory tract, urgent need to act and potential for catastrophic consequences. This high-risk, life-threatening clinical scenario requires specialized knowledge and a well-designed treatment protocol to achieve a positive outcome. In this review, we report a case of airway compromise secondary to wound hematoma following anterior cervical discectomy and fusion, followed by a review of relevant literature, anatomy, etiologic factors and diagnostic considerations. We also propose guidelines for the prevention and management of postoperative airway obstruction due to wound hematoma.
Anterior cervical spine surgery; adverse event; airway obstruction; hematoma.
To develop a thoracoscopic technique for correcting and/or removing an intrathoracic disease process using our existing operating room equipment and without a “small thoracotomy.”
Methods and Procedures:
Fifty-eight patients from October 1994 to April 1998 were prospectively studied. All were undergoing procedures involving the removal of a suspected benign (or infectious) pleural process or a retained blood clot. Three or four thoracic ports were used in all cases. Straight and curved suction curettage cannulae (with finger valve attachment) ranging from 8 to 16 French were available for use. Intermittent variable suction (between zero and 60 mm Hg) was used in all cases. Dependent upon the size and adherence of the lesion to be removed, the pressure was determined by the surgeon and regulated by the circulating nurse in the room. In each case, a trap system was used for retrieval of the specimen. One lung ventilation was used in every case, and when suction was used one of the ports was kept “open” to allow room air to enter the chest cavity.
All patients in our series had their procedures completed without the need for any kind of open thoracotomy. Pre and postoperative diagnosis concurred in all 10 patients, and no complications occurred (specifically, no injury to the lung tissue or chest wall structures). Operative time ranged from 45 minutes to 180 minutes with a mean of 75 minutes. In all cases of a hemothorax, a cell saver system was used for an average of one unit of blood autotransfused per case.
New techniques do not always require the purchase of new equipment. Tight hospital budgets are forcing surgeons to rely on redefining uses of instrumentation already available in solving surgical problems. We believe that the use of this instrumentation will provide another avenue for surgeons to successfully complete a procedure thoracoscopically without the need for a thoracotomy. It is through multidisciplinary conferences such as the Society of Laparoendoscopic Surgeons that ideas such as this are propagated.
Thoracoscopy; Retained clot; Pleural lesion
The effects of environmental temperature on thrombosis in circulating blood were tested in the extracorporeal loop by the method previously described. Cold (7° to 15°C.) about the collodion tube retards the clotting of circulating blood. Obstruction of the arterial cannula occurs after from 15 to 25 minutes. Heat (40° and 55°C.) tends to hasten clotting; obstruction by red clot takes place after from 4 to 6 minutes and from 2 to 4 minutes, respectively. In the latter case no characteristic thrombus structure may be seen. These results were what might be expected. The formation of white thrombi occurs even under the influence of cold, and they continue to form and grow as long as the circulation continues. When the carotid artery is partially occluded and the blood stream slowed, after the injection of the anticoagulant, the blood has a tendency to form red thrombi on the foreign surface of the vascular loop. The thrombi are deposited chiefly in the arterial half of the apparatus, especially at the bottom of the arterial end of the collodion tube, just as in the case of Aschoff's sand experiments. In spite of incoagulability of heparinized blood, red clots, with interwoven fibrin bands, are found. Also very tiny white thrombi may form in other parts of the collodion tube. The effect of complete obstruction of the carotid artery and jugular vein on thrombus formation was studied after the use of anticoagulant. When the carotid artery is obstructed the formation of white thrombi is negligible and sedimentation of erythrocytes and deposition of fibrin appear throughout the apparatus; then the blood, at a standstill, clots very slowly. When the jugular vein is obstructed, dislodgment of platelet thrombi probably results from the pulsating movement, and sedimentation of erythrocytes follows, forming mixed thrombi. The dislodged white thrombi tend to gather in the bottom of the tubes of the widest caliber, especially in the collodion tube.
Severe inflammation after cardiopulmonary bypass with the vasculitis of the acral extremity and vertebro-basilar arterial system leads to the locked-in syndrome and blue toe syndrome. In broad terms, systemic, idiopathic, and environmental factors provoke syndromes that present with digital discoloration or the blue toe syndrome. Painful digital discoloration, accompanied by ulceration, suggests vasculitis, involving small blood vessels. Definitive diagnosis usually requires histological documentation because vasculitic syndromes have no pathognomonic clinical features or laboratory test results.
The case introduced herein is that of a woman who developed the locked-in syndrome in conjunction with quadriplegia, loss of facial movement, speech loss, and loss of horizontal eye movements. She had initially presented with severe mitral stenosis and left atrial clot and undergone mitral valve replacement and clot extraction. The patient expired from multiple organ failure despite prolonged ventilatory support, including tracheotomy, and meticulous nursing care and antibiotic prophylaxis. Given the previously reported partial recovery from this syndrome with the use of steroids, we would advocate the use of such pharmacological agents.
Cardiopulmonary bypass; Postoperative complications; Cardiac surgical procedures; Blue toe syndrome
AIM: To compare the International Sensitivity Index (ISI) of the Thrombotest reagent used with a steel ball coagulometer (KC) to the ISI of the same reagent used with the manual (tilt tube) technique. METHODS: The study was carried out by eight laboratories using their own KC instrument and method of testing. All laboratories used the same batch of Thrombotest to determine the clotting times of fresh blood samples from 20 local healthy volunteers and 60 patients on long term oral anticoagulant therapy. KC clotting times were plotted against manual clotting times on double logarithmic scales. Orthogonal regression lines were calculated to assess the ISI. RESULTS: In two laboratories the ISI of the KC method was lower than that of the manual method; these differences, however, were 2% or less. In the other laboratories no clinically important differences were observed between ISI values obtained. However, the clotting times determined with the KC methods were shorter than the manual values. CONCLUSIONS: The ISI of Thrombotest determined with the KC methods was very similar to the manual value. Therefore, use of the ISI value supplied by the manufacturer without adjustment is justified. The mean normal prothrombin time, however, must be determined locally.
We describe the very unusual case of a patient with a large, free-floating left-atrial thrombus secondary to severe mitral stenosis, in whom the peculiar symptoms and complications of a ball thrombus were absent. The patient's only symptom before the episode reported here was mild dyspnea, which was attributed to mitral stenosis. She experienced neither embolism nor syncope. While even her clinical signs did not indicate a left-atrial ball thrombus, both echocardiography and angiography showed a free-floating thrombus. Because of the risk of stroke and acute obstruction of the mitral valve, emergency surgery was performed upon diagnosis of the ball thrombus. The surgery, which consisted of removing the thrombus and replacing the mitral valve with a mechanical prosthesis, was uneventful. A computed tomographic brain scan prior to discharge did not detect any cerebral infarction.
A case is presented in which the mitral and tricuspid valves were replaced by a ball-valve prosthesis. The patient was admitted as an emergency 18 months later with the clinical picture of acute venous inflow obstruction to the heart due to tricuspid ball-valve prosthesis obstruction. Successful replacement under emergency open heart surgery, using assisted circulation, is described.
A mechanical prosthetic heart valve can become acutely obstructed despite anticoagulation therapy. This can be a life-threatening complication. We report the case of a 38-year-old woman who survived obstruction of her Sorin prosthetic mitral valve. She was admitted to the hospital because of severe pulmonary edema. On auscultation, mechanical valve sounds were absent. Transthoracic echocardiography showed an immobile mechanical valve. The patient suffered a cardiac arrest while being prepared for surgery, but she underwent successful mitral valve replacement after cardiopulmonary resuscitation. When patients with prosthetic mitral valves present with acute dyspnea, the possibility of an obstructed prosthetic valve must be considered in the differential diagnosis.
Blood clotting is a precise cascade engineered to form a clot with temporal and spatial control. Current control of blood clotting is achieved predominantly by anticoagulants and thus inherently one-sided. Here we use a pair of nanorods (NRs) to provide a two-way switch for the blood clotting cascade by utilizing their ability to selectively release species on their surface under two different laser excitations. We selectively trigger release of a thrombin binding aptamer from one nanorod, inhibiting blood clotting and resulting in increased clotting time. We then release the complementary DNA as an antidote from the other NR, reversing the effect of the aptamer and restoring blood clotting. Thus, the nanorod pair acts as an on/off switch. One challenge for nanobiotechnology is the bio-nano interface, where coronas of weakly adsorbed proteins can obscure biomolecular function. We exploit these adsorbed proteins to increase aptamer and antidote loading on the nanorods.
Patient: Female, 14
Final Diagnosis: Postobstructive pulmonary edenma
Symptoms: Chest indrawing • bilateral pulmonary crepitations • tachypnea
Clinical Procedure: Controlled ventilatory support • positive end expiratory pressure
Specialty: Intensive care
Unusual clinical course
Postobstructive pulmonary edema (POPE) is a life-threatening complication that occurs after the relief of an upper airway obstruction. POPE occurs rarely in children, primarily after non-lethal hanging.
We report the case of a 14-year-old girl who developed POPE after accidental near hanging. She had chest in-drawing, the SpO2 was 81% on room air, and pulmonary auscultation revealed bilateral crepitations. The chest x-ray showed bilateral diffuse infiltrates consistent with pulmonary edema. The intensive care management consisted of controlled ventilatory support with high-level positive end expiratory pressure. On the third day of hospitalization, the patient was weaned from the ventilator and extubated with a full recovery.
This case confirms the importance of early recognition of POPE and the value of adapted treatment, which can lead to a favorable outcome and full recovery in cases of near hanging.
post-obstructive pulmonary edema; near hanging; child
Experimental hypercalcaemia was induced in rats by (1) transplantation of the solid Walker 256 tumour, and (2) intraperitoneal injections of calcium gluconate. Whole blood clotting was studied by means of thromboelastography and whole blood clotting times in polystyrene and glass test tubes. At serum calcium levels between 10·3 and 11·5 m-equiv/l a slight delay in clot formation was found which was reversible by the addition of EDTA to whole blood. Acute, calcium-gluconate-induced hypercalcaemia, however, leads to a significant shortening of the clotting time in the polystyrene tube and to a lesser degree in the glass tube. Maximal factor XII activation in vitro with ellagic acid levels the difference of clotting times again. From these experiments it is concluded that acute hypercalcaemia induces a hypercoagulable state, possibly by partial contact activation, and thus may favour thrombus formation in vivo.
Spontaneous pneumothoraces are believed to arise when air from the supplying airway exit via a ruptured visceral pleural bleb into the pleural cavity. Endobronchial one-way valves (EBVs) allow air exit (but not entry) from individual segmental airways. Systematic deployment of EBVs was applied to three patients with secondary spontaneous pneumothoraces and persistent airleak. In all cases, balloon-catheter occlusion of the upper lobe bronchus stopped the airleak. EBVs applied to individual upper lobe segmental airways failed to terminate the airleak, which only stopped after placements of multiple EBVs to occlude all upper lobe segments. The observation questions the traditional belief of 'one-airway-one-bleb-one-leak' in spontaneous pneumothorax.
Thrombolysis is a dynamic and time-dependent process influenced by the haemodynamic conditions. Currently there is no model that allows for time-continuous, non-contact measurements under physiological flow conditions. The aim of this work was to introduce such a model.
The model is based on a computer-controlled pump providing variable constant or pulsatile flows in a tube system filled with blood substitute. Clots can be fixed in a custom-built clot carrier within the tube system. The pressure decline at the clot carrier is measured as a novel way to measure lysis of the clot. With different experiments the hydrodynamic properties and reliability of the model were analyzed. Finally, the lysis rate of clots generated from human platelet rich plasma (PRP) was measured during a one hour combined application of diagnostic ultrasound (2 MHz, 0.179 W/cm2) and a thrombolytic agent (rt-PA) as it is commonly used for clinical sonothrombolysis treatments.
All hydrodynamic parameters can be adjusted and measured with high accuracy. First experiments with sonothrombolysis demonstrated the feasibility of the model despite low lysis rates.
The model allows to adjust accurately all hydrodynamic parameters affecting thrombolysis under physiological flow conditions and for non-contact, time-continuous measurements. Low lysis rates of first sonothrombolysis experiments are primarily attributable to the high stability of the used PRP-clots.
We present a case of a life-threatening almost complete airway obstruction resulting from poorly differentiated thyroid carcinoma in a 48-year-old male. Airway obstruction may lead to unexpected mortality by suffocation and patients with poorly differentiated thyroid carcinoma usually have a fast deterioration and fatal outcome. In the case presented, we describe a safe and effective treatment strategy. Assisted by femoro-femoral cardiopulmonary bypass oxygenation, a tracheal stent was implanted successfully. Following surgery there were no complications, and chemoradiotherapy resulted in the relief of obstructing symptoms and improved the quality of life of the patient. This case indicates that femoro-femoral cardiopulmonary bypass provides adequate oxygen support to undergo further management and that tracheal stent implant is an effective emergent measure to relieve severe airway obstruction in patients with poorly differentiated thyroid carcinoma.
thyroid cancer; airway obstruction; cardiopulmonary bypass; stents
A patient is reported who had biliary tract obstruction secondary to infection of the common bile duct with Candida albicans, with the formation of a fungus ball. Treatment consisted of surgical removal of the fungus ball and drainage. Chemotherapy was not necessary. Ureteral obstruction through fungus ball formation, and even pulmonary fungus ball formation, has been attributed to candida, but this is the first case reported, to our knowledge, of bile duct obstruction.
In patients with traumatic injury of an upper limb it is often necessary to both secure intravenous (IV) access and record blood pressure noninvasively in the other upper limb. This may cause intermittent obstruction to the flow of IV fluids during cuff inflation. Also backflow of blood into the IV tubing when the cuff is inflated and the temporary stasis which occurs predisposes to clotting of blood in the IV tubing/catheter. Overenthusiastic efforts to push IV fluids without disconnection and flushing of IV line may pose a possible risk of embolizing the clotted blood thrombus into circulation. We describe a simple technique to prevent backflow of blood into the IV tubing when both intravenous fluid infusion and non-invasive blood pressure cuff are in the same limb. This may prevent clot formation and eliminate the risk of an iatrogenic thrombo-embolism.
Negative pressure pulmonary oedema (NPPO) is a life threatening condition, manifested due to upper airway obstruction in a spontaneously breathing patient. Upper airway obstruction caused by classic laryngeal mask airway (cLMA) and ProSeal laryngeal mask airway (PLMA) has been reported, and NPPO has also been reported following the use of cLMA. Search of literature did not confirm NPPO following the use of PLMA. We encountered a female patient of NPPO scheduled for incision and drainage of an abscess who had signs of airway obstruction following PLMA insertion. Multiple attempts were made to get patent airway without success. PLMA was replaced with endotracheal tube following which pink frothy secretion appeared in breathing circuit. Patient was managed successfully with ICU care.
Airway obstruction; negative pressure; negative pressure pulmonary oedema; ProSeal laryngeal mask airway
1. Artificial heart valves have been in use for over five decades to replace diseased heart valves. Since the first heart valve replacement performed with a caged-ball valve, more than 50 valve designs have been developed, differing principally in valve geometry, number of leaflets and material. To date, all artificial heart valves are plagued with complications associated with haemolysis, coagulation for mechanical heart valves and leaflet tearing for tissue-based valve prosthesis. For mechanical heart valves, these complications are believed to be associated with non-physiological blood flow patterns.
2. In the present review, we provide a bird’s-eye view of fluid mechanics for the major artificial heart valve types and highlight how the engineering approach has shaped this rapidly diversifying area of research.
3. Mechanical heart valve designs have evolved significantly, with the most recent designs providing relatively superior haemodynamics with very low aerodynamic resistance. However, high shearing of blood cells and platelets still pose significant design challenges and patients must undergo life-long anticoagulation therapy. Bioprosthetic or tissue valves do not require anticoagulants due to their distinct similarity to the native valve geometry and haemodynamics, but many of these valves fail structurally within the first 10–15 years of implantation.
4. These shortcomings have directed present and future research in three main directions in attempts to design superior artificial valves: (i) engineering living tissue heart valves; (ii) development of advanced computational tools; and (iii) blood experiments to establish the link between flow and blood damage.
aortic; bileaflet; circulation; haemodynamics; heart valve; mechanical; mitral; prosthesis; trileaflet
Thrombus formation has been studied in normal rabbits with an experimental method of establishing extracorporeal circulation. In the normal animal circulation in the extracorporeal loop usually ceases in from 6 to 10 minutes, or at most, in very large and vigorous animals, in 25 minutes.1 Cessation of the circulation is due most frequently to obstruction of the venous cannula (sometimes of the arterial cannula) by a mass of white thrombi and secondary fibrin formation around it. The site of the clot is determined somewhat by the swiftness of the blood stream. In the collodion tube red mural thrombi are obtainable as a rule. They are flat and present a wide base resting on tiny white thrombi. After the complete obstruction of the circulation, the blood in the apparatus clots very rapidly. When the obstruction occurs very quickly either in the arterial or venous cannula, or when the blood stream is very slow, the clotting in the loop may occur before platelets are laid down in large numbers or before the formation of the white thrombi is evident. Mixed thrombi are found in the jugular vein, and have their inception in the white thrombi, in the cannula or from the injured intima. They extend in the direction of the blood flow.
α2-Plasmin inhibitor (α2PI) is a recently characterized, fast-reacting plasmin inhibitor in human plasma that appears to play an important role in regulation of in vivo fibrinolysis. We report here a case of complete deficiency of α2PI in man. The patient, a 25-yr-old Japanese man, had a life-long severe bleeding tendency (hemarthrosis and excessive bleeding after trauma). The following tests were within normal limits: platelet count, bleeding time, thrombin time, prothrombin time, partial thromboplastin time, titers of known clotting factors, platelet glass bead retention, Factor VIII-related antigen, platelet aggregation by ADP, collagen and ristocetin, and clot retraction. Routine liver function tests were also normal. The only abnormal finding was that whole blood clot lysis was extemely rapid and was complete in 4-8 h. The concentration of plasma protease inhibitors, including α2-macro-globulin, antithrombin III, α1-antitrypsin, and C1̄INH, were all normal. The concentration of α2-PI in the patient's plasma, assayed by immunological methods, was <0.1 mg/100 ml (normal concentration, 6.1±0.88 mg/100 ml [mean±SE]) and functional assays showed a complete deficiency of α2PI. Addition of purified α2PI to the patient's whole blood completely corrected the accelerated fibrinolysis. The patient's parents, four siblings, and four other members of this family were asymptomatic, but the titers of α2PI in their plasmas were ≅50% of normal pooled plasma. There were three consanguineous marriages in this family, and the α2PI deficiency appears to have been inherited as an autosomal recessive trait. We speculate that α2PI deficiency in this patient has led to uninhibited in vivo fibrinolysis that probably causes the severe hemorrhagic tendency. Thus, this study indicates the important role of α2PI in hemostasis.