Search PubMed⌕ Search

Biomedical subjects

J A Caprini

Publications and source records attributed to J A Caprini.

At least 37 records · Page 2Linked to original sources
PubMed1995

Postoperative hypercoagulability and deep-vein thrombosis after laparoscopic cholecystectomy.

Patients who undergo laparoscopic cholecystectomy (LC) are operated on under general anesthesia, in a reverse Trendelenburg position, with 12-15-mmHg pneumoperitoneum. All of these factors can induce venous stasis of the legs, which may lead to postoperative deep-vein thrombosis (DVT). The objectives of this study were to assess the degree of hypercoagulability and to determine the rate of postoperative DVT in a group of 100 patients in whom LC was completed. Whole-blood thrombelastography (TEG) and plasma-activated partial thromboplastin time (PTT) determination were carried out preoperatively and on the 1st postoperative day. All patients received pre-, intra-, and postoperative graduated compression stockings and sequential pneumatic compression devices until fully ambulatory. Twenty-six percent of the patients with a risk score > 4, or a post-operative TEG index > +5.0, received subcutaneous heparin (5,000 units b.i.d.), beginning in the postoperative period and continuing for 4 weeks as an outpatient. A complete venous duplex scan of both legs was performed on the 7th postoperative day, at the time of their office visit. Our results revealed significant postoperative hypercoagulability for the TEG index (P < 0.005) and for PTT (P < 0.05). One patient had an asymptomatic DVT (1%), and no side effects from the mechanical or pharmacological prophylaxis occurred in this series. These data suggest that the low incidence of thrombosis in the face of theoretical and laboratory evidence of postoperative hypercoagulability may reflect an effective prophylactic regime.(ABSTRACT TRUNCATED AT 250 WORDS)

Bandages↗
PubMed1995

Modifications of plasma levels of tissue factor pathway inhibitor and endothelin-1 induced by a reverse Trendelenburg position: influence of elastic compression--preliminary results.

PURPOSE: The purpose of this study was to assess the effects of the passive 45-degree reverse Trendelenburg position and graduated compression stockings (GCS) on plasma tissue factor pathway inhibitor (TFPI) and endothelin-1 levels in a group of volunteers. METHODS: Ten healthy subjects lay on an examining table for 30 minutes while baseline measurements were made. The table was then tilted to a 45-degree upright position for 60 minutes, and measurements were repeated. On a different day, subjects were tilted again, but on this occasion they wore thigh-length GCS. Blood was drawn before and 60 minutes after tilting during both sessions, and plasma TFPI and endothelin-1 were obtained. Cross-sectional areas of the calf medial gastrocnemius vein, before and after tilting, were measured by a duplex scanner. RESULTS: Upright tilting induced a significant dilation of the medial gastrocnemius veins that was partially corrected by the use of elastic stockings. Similarly, endothelin-1 levels significantly increased after tilting. The use of GCS did not modify these differences. On the other hand, although TFPI levels were not affected by tilting without stockings, they were significantly elevated after tilting when GCS were used. CONCLUSIONS: Upright passive tilting induces significant dilation of the deep calf veins and is associated with a significant increase in plasma levels of endothelin-1, whereas TFPI levels remain unchanged. The use of elastic stockings reduces the degree of calf distention but does not prevent an increase in endothelin-1. TFPI levels are significantly increased after tilting when GCS are used. This might represent a previously unknown mechanism of action of elastic stockings with interesting potential for deep vein thrombosis prophylaxis. More studies are warranted in a larger series to confirm these results.

Adult↗
PubMed1995

Venous duplex imaging follow-up of acute symptomatic deep vein thrombosis of the leg.

PURPOSE: The purpose of this study was to evaluate the rate of resolution of deep vein thrombosis (DVT) in the leg, by means of duplex imaging, in patients with symptoms during a 6-month period after initial diagnosis. METHODS: Seventy-three limbs in 69 patients with acute DVT diagnosed by duplex imaging received conventional heparin and warfarin treatment and underwent subsequent duplex studies 1, 4, 12, and 24 weeks after the initial diagnosis. The objectives of the study were to document (1) the rate or complete resolution of DVT, (2) the proportion of unstable, floating thrombi, and (3) the development of chronic damage as a result of vessel wall scarring. RESULTS: The rate of normalization of DVT 6 months after diagnosis was 78% in the common femoral vein, 70% in the superficial femoral vein, 75% in the popliteal vein, and 70% in the calf veins examined at the scheduled intervals. Twenty-six percent of thrombi were considered unstable on the baseline examination. The average number of days necessary for these thrombi to become stable was 10.7 days. Damage to the vessel wall or valves was documented in 44% of the patients. CONCLUSIONS: Rates of resolution of DVT were similar for the different veins of the leg studied. There was a high proportion of unstable thrombi, which present a high potential risk of embolization. Serial duplex scanning after DVT renders important information with regard to thrombus resolution, propagation, and attachment to the vein wall.

Acute Disease↗
PubMed1995

Perspectives on thromboelastography.

The knowledge of these sources of error together with strict methodology assure reliable results and avoid what some authors consider limitations of the test. These so-called limitations are actually due to incomplete information or insufficient experience. It is our opinion that the key for success when using TEG is to use the test in those cases for which it has been indicated. Also, the fact that TEG is a global test of coagulation should be kept in mind and therefore the need for additional hemostatic tests should be evaluated when applicable (Fig.3). According to this review, the established applications of TEG are as follows: (1) detection of hypercoagulable states, particularly in the postoperative period and for patients with malignancies; (2) management of patients who are administered intravenous heparin; (3) monitoring the coagulation state during liver transplantation; (4) monitoring the coagulation state and management of patients during cardiopulmonary bypass; and (5) diagnosis and treatment of hematologic dysfunctions, particularly hemophilia. Management of patients under warfarin administration, as well as monitoring of the adjustment of subcutaneous heparin prophylaxis in several surgical procedures, should probably belong to this list, but further studies are needed to confirm these roles. Used by experienced hands, TEG is a valuable hemostatic test, the future of which is already present.

Artifacts↗
PubMed1995

The haemostatic effectiveness of autologous platelet rich plasma sequestered after heparin administration and institution of cardiopulmonary bypass.

Preoperative harvesting and postoperative reinfusion of autologous platelet rich plasma (PRP) has been reported to decrease blood loss as well as the requirement for homologous blood transfusion following cardiopulmonary bypass (CPB). We have developed a technique of intraoperative PRP sequestration which occurs during the initial period of CPB after the patient's circulation is supported and heparin has been given (PRP+). This process does not require any additional hardware, personnel or expense and it is performed without difficulty or complication. To evaluate the effect of PRP+ sequestration and reinfusion on blood loss and homologous blood requirement after CPB, we randomly assigned 126 consecutive patients undergoing elective open heart surgery into the experimental group 1 (PRP+) (n = 64) or the control (no platelet pheresis) group 2 (n = 52). A third group (n = 10) were not included in the randomization. Patients in group 3 had PRP prepared by conventional techniques (PRPc) prior to heparin administration and given to the patient after protamine infusion. Aggregation and activation studies were performed on the PRP+, PRPc, and blood bank platelets (BBP). Per cent aggregation of PRP in response to ADP was superior to that of BBP. There were no significant differences in ADP induced aggregation between PRP+ and PEPc. There was no significant difference in platelet activation (CD62) or number between the three groups. Patients infused with PRP+ showed significantly increased aggregation to ADP when compared with untreated patients 120 minutes after return to the ICW. Furthermore, more homologous haemostatic components (platelets/fresh frozen plasma) were required in the control group. We have demonstrated that collection of autologous PRP+ after administration of heparin does not interfere with its haemostatic effectiveness compared with PRPc prepared before the initiation of bypass. Moreover, this can be performed universally in haemodynamically unstable patients without any additional costs.

Aged↗
PubMed1994

Prevention of postoperative venous thromboembolism following laparoscopic cholecystectomy.

Advantages of laparoscopic cholecystectomy are less patient discomfort and shorter hospital stay than with the traditional open approach. Nevertheless, this operation is performed under general anesthesia, using muscle relaxants and pneumoperitoneum, with most patients in the reverse Trendelenburg position. It has been shown that this procedure is associated with significant hypercoagulability and dilation of the veins of the leg. We review the role of these factors as potential risk factors for the development of postoperative venous thromboembolism and also report the rate of thromboembolic complications following laparoscopic cholecystectomy. Based on the available evidence, it is concluded that laparoscopic cholecystectomy, despite being a "minimally invasive procedure," may be associated with a definite risk of developing postoperative venous thromboembolism that could extend beyond hospital discharge. Accordingly, thrombosis prophylaxis should be considered for these patients.

Cholecystectomy, Laparoscopic↗
PubMed1994

Prevention of venous thromboembolism in North America: results of a survey among general surgeons.

PURPOSE: The purpose of this study was to analyze current attitudes toward the prevention of postoperative venous thromboembolism among North American general surgeons. METHODS: A survey regarding awareness of the problem of venous thromboembolism and preferred modalities of prophylaxis was sent to 3500 randomly selected Fellows of the American College of Surgeons. RESULTS: A total of 1018 (29.1%) surveys was returned. Most of the responding surgeons consider venous thromboembolism a serious health problem. Ninety percent of the surgeons use prophylaxis against venous thromboembolism routinely. The most frequently used modalities are intermittent pneumatic compression, low-dose heparin, and elastic stocking. A combination of physical and pharmacologic methods is used by one fourth of respondents, and only 50% start pharmacologic prophylaxis before the surgical procedure. The thrombosis risk factors that are most frequently considered by surgeons when deciding about using prophylaxis are history of venous thromboembolism, immobility, and length of operation. CONCLUSIONS: North American surgeons who responded to this survey are well aware of the problem of venous thromboembolism and their approach to prevention has been significantly modified in the last 10 years. Compared with similar European surveys this survey reveals a higher implementations of physical methods such as intermittent pneumatic compression and elastic stockings. Because of the limited response rate and possibility of sampling bias, these findings should be interpreted with caution.

Adult↗
PubMed1994

Cost-effective laparoscopic cholangiography.

Cholangiography during laparoscopic cholecystectomy is an invaluable tool for detecting occult bile duct calculi and identifying biliary tract anatomy. Attaining proficiency in cannulation of the cystic duct is an important goal for those interested in laparoscopic transcystic common duct manipulation. A variety of disposable equipment is available for this purpose, but most systems are rather costly for the patient. This report describes our experience with a technique for cholangiography that is both highly successful and inexpensive. It consists of a reusable 8" stainless steel blunt-tipped needle and trocar introducer through which a 4-French, disposable, end-hole catheter is placed into the duct and secured with a single clip. A 0.25 hydrophilic guidewire is placed through this catheter to facilitate proper catheter placement when cystic duct cannulation is difficult. Blunt-tip reusable nylon rods are placed in each trocar site to provide unobstructed visualization of the biliary tract during the fluoroscopy or filming procedures. Thirty-seven consecutive patients had successful cholangiograms during laparoscopic cholecystectomy using this technique, including the use of the guidewire in five patients, without complications. The catheter was advanced into the common duct and secured with clips to provide postoperative duct drainage in two patients with unsuspected common duct stones and very small cystic ducts until successful postoperative endoscopic retrograde cholangiopancreatography (ERCP) stone extractions were done. Three additional patients had occult common duct stones discovered during operative cholangiography. All patients were successfully treated postoperatively with ERCP sphincterotomy and stone extraction without complications. Our technique provides successful, cost-effective operative cholangiography, including cases when cystic duct cannulation is difficult.(ABSTRACT TRUNCATED AT 250 WORDS)

Catheterization↗
PubMed1993

Venous thromboembolism after hospital discharge.

Several methods of prophylaxis have significantly reduced the risk of developing VTE during hospital admission. There is a current tendency toward a reduction in the hospital stay, which does not necessarily mean that patients are protected from experiencing thrombotic complications after leaving the hospital. A number of patients will develop DVT and PE after hospital discharge if prophylaxis is prematurely discontinued while they persist at risk. Further studies are necessary to establish whether extending prophylaxis beyond discharge will reduce the rate of late-onset thromboses and which are the best prophylactic alternatives for the different patient groups at risk. Meanwhile, it is our standard of practice to utilize a combination of GES and either low-dose heparin or warfarin, at least for 3 or 4 weeks after discharge in high-risk patients. In countries where low molecular weight heparins are available, these agents represent an attractive alternative to unfractionated heparin because of their better dosage schedule and safety profile.

Humans↗
PubMed1991

Iatrogenic biliary tract complications: radiologic features and clinical significance.

Thirteen intrahepatic and 22 extrahepatic biliary tract complications were detected radiologically in 35 adult patients who had undergone cholecystectomy and bile duct exploration. Intraoperative usage of Fogarty balloon catheters to extract biliary calculi without fluoroscopic guidance resulted in focal ectasia or rupture of intrahepatic radicles in two and seven cases, respectively. Metallic surgical instruments such as Bakes dilators and biliary forceps or clamps accounted for most of the common duct injuries; these were manifested as submucosal dissection (two cases), transmural laceration (four cases), or localized trauma with subsequent stricture (three cases). Technical mishaps during T-tube placement led to common duct perforation (four cases) and extraluminal malposition of T tubes (three cases). The remaining complications included choledochoduodenal fistula (three cases), biliovenous fistula (two cases), biloma (three cases), and retained intraductal fragments of biliary drainage catheters (two cases). Knowledge about radiologic features and causal factors of such iatrogenic processes can play a crucial role in their prevention, correct diagnosis, and management.

Adolescent↗