Venous thromboembolism in urologic surgery: prophylaxis, diagnosis, and treatment

Venous thromboembolism (VTE) represents one of the most common and potentially devastating complications of urologic surgery. With VTE's rapid onset of symptoms, association with a precipitous clinical course, and high mortality rate, all urologists should be well versed in appropriate prophylaxis, prompt diagnosis, and expeditious treatment. A MEDLINE(R) search was performed for articles that examined the incidence, diagnosis, and treatment of VTE in urologic surgery. Additional articles were reviewed based on cited references. There is a paucity of prospective studies on VTE in the urologic literature with most recommendations for urologic surgery patients being extrapolated from other surgical disciplines. Retrospective studies place VTE incidence rates in major urologic surgeries among the highest reported-highlighting the importance of thromboprophylaxis. Conversely, VTE was rarely reported in association with endoscopic and laparoscopic procedures making mechanical thromboprophylaxis sufficient. Recent literature reveals delayed VTE occurring after hospital discharge to be a persistent threat despite inpatient preoperative prophylaxis. Computed tomographic angiography has emerged as the test of choice for diagnosing pulmonary embolism, whereas lower extremity duplex sonography is recommended for diagnosing deep venous thrombosis. Traditional angiography is rarely used. Treatment of VTE involves therapeutic anticoagulation for various lengths of time based on presence and reversibility of patient risk factors as well as number of events. Perioperative thromboprophylaxis should be considered in all major urologic surgeries. Urologists should be familiar with incidence rates, recommended prophylaxis, appropriate diagnosis, and treatment recommendations for VTE to minimize morbidity and mortality. The limited number of prospective, randomized, controlled trials evaluating the use of thromboprophylaxis in urologic surgery demonstrates the need for further research.

A case with sudden onset of position-dependent hypoxemia caused by reopening of foramen ovale

We report a case of a 68-year-old woman with sudden onset of position-dependant hypoxemia after recovering from pulmonary embolism. Transesophageal echocardiography (TEE) and cardiac catheterization revealed the presence of patent foramen ovale (PFO) and right-to-left shunting with no evidence of the right-to-left pressure gradient especially in the right lateral decubitus position. Surgical closure of the PFO was performed because the right-to-left shunting caused position-dependent severe hypoxemia. At operation, it was noted that the patient's enlarged aortic root pressed the heart inferiorly and compressed the upper part of the right atrium. A large Eustachian valve, which is an embryonic remnant of the right valve of the sinus venosus, was observed in the right atrium. Preceding pulmonary embolism could lead to a temporal elevation of the right heart and pulmonary arterial pressures and it caused the reopening of the closed foramen ovale. To the best of our knowledge, this is the first case of reopening of the foramen ovale causing sudden onset of position-dependent hypoxemia.

The best predictor for right ventricular dysfunction in acute pulmonary embolism: comparison between electrocardiography and biomarkers

Background and Objectives

Right ventricular (RV) dysfunction is associated with a poor prognosis in patients with an acute pulmonary embolism (APE). We studied the role of electrocardiography and biomarkers for early detection and recovery of right ventricular dysfunction (RVD) in APE.

Subjects and Methods

The medical records of 48 consecutive patients diagnosed with APE using CT-angiography, at the Kangdong Sacred Heart Hospital, between January 2004 and February 2008 were reviewed retrospectively. RVD was assessed by serial echocardiography (ECG). Patients with one of the following were considered to have RVD: 1) RV dilatation (enddiastolic diameter >30 mm in the parasternal long axis view), 2) RV free wall hypokinesia, and 3) paradoxical septal systolic motion. We compared the electrocardiographic findings and the biomarkers for the early detection of RVD.

Results

The electrocardiographic findings showed T-wave inversion (TWI) in leads V1 to V3 with a sensitivity of 75% and a specificity of 95%, and a diagnostic accuracy of 80% for the detection of RVD, with positive and negative predictive values of 95.5% and 73.1%, respectively; these results were better than the biomarkers such as cardiac enzymes or B-type natriuretic peptide (BNP) for the early detection of RVD. TWIs persisted throughout the period of RVD, in contrast to a transient S1Q3T3 pattern detected during the acute phase only.

Conclusion

TWIs in leads V1 to V3 had the greatest sensitivity and diagnostic accuracy for early detection of RVD, and normalization of the TWIs was associated with recovery of RVD in APE.

A re-appraisal of warfarin control in the treatment of deep vein thrombosis and / or pulmonary embolism

BACKGROUND

Warfarin is commonly used for management of deep vein thrombosis (DVT) and pulmonary embolism (PE), controlling therapy by means of the International Normalized Ratio (INR).

OBJECTIVES

To identify differences in INR results between patients with thromboembolic and haemorrhagic complications and controls.

METHODS

Two nested case-control studies from within a controlled trial of the duration of warfarin therapy (47 thrombotic and 16 haemorrhagic complications).

RESULTS

Patients whose thromboembolism failed to resolve during treatment or recurred during or after treatment had non-significantly lower INR levels than matched controls (geometric mean 2.2 versus 2.3, p = 0.12). Patients with haemorrhage also had not statistically significant lower INR levels than their matched controls (2.1 versus 2.3, p = 0.22). The variability of INR levels was similar in both case groups and controls. The mean percentage of INR levels in the therapeutic range 2 - 3 was almost identical in thrombotic cases and controls (56.5% versus 56.1%). Compared to the haemorrhagic group, better control was achieved in controls (61.5% versus 43.0%, p=0.01), but controls had slightly more INR values above the therapeutic range (12.1% versus 10.5%, p = 0.74) whilst haemorrhagic cases had more INR values below the therapeutic range (46.6% versus 26.4%, p = 0.03).

CONCLUSION

In this study, higher INR levels were not associated with haemorrhage suggesting that, for patients being treated for DVT/PE, a modest increase in the target therapeutic range could be considered.

MR diagnosis of a pulmonary embolism: comparison of P792 and Gd-DOTA for first-pass perfusion MRI and contrast-enhanced 3D MRA in a rabbit model

Objective

To compare P792 (gadomelitol, a rapid clearance blood pool MR contrast agent) with gadolinium-tetraazacyclododecanetetraacetic acid (Gd-DOTA), a standard extracellular agent, for their suitability to diagnose a pulmonary embolism (PE) during a first-pass perfusion MRI and 3D contrast-enhanced (CE) MR angiography (MRA).

Materials and Methods

A perfusion MRI or CE-MRA was performed in a rabbit PE model following the intravenous injection of a single dose of contrast agent. The time course of the pulmonary vascular and parenchymal enhancement was assessed by measuring the signal in the aorta, pulmonary artery, and lung parenchyma as a function of time to determine whether there is a significant difference between the techniques. CE-MRA studies were evaluated by their ability to depict the pulmonary vasculature and following defects between 3 seconds and 15 minutes after a triple dose intravenous injection of the contrast agents.

Results

The P792 and Gd-DOTA were equivalent in their ability to demonstrate PE as perfusion defects on first pass imaging. The signal from P792 was significantly higher in vasculature than that from Gd-DOTA between the first and the tenth minutes after injection. The results suggest that a CE-MRA PE could be reliably diagnosed up to 15 minutes after injection.

Conclusion

P792 is superior to Gd-DOTA for the MR diagnosis of PE.

The pulmonary embolism severity index in predicting the prognosis of patients with pulmonary embolism

BACKGROUND/AIMS

Many prognostic models have been developed to help physicians make medical decisions on treating patients with pulmonary embolism. Among these models, the Pulmonary Embolism Severity Index (PESI) has been shown to be a successful risk stratification tool for patients with acute pulmonary embolism. The PESI, however, had not been applied to patients with pulmonary embolism in Korea.

METHODS

The patients included in this study were diagnosed by computed tomography at Inje University's Ilsan Paik Hospital between December 1999 and March 2007. Risk stratification for the patients was performed using the PESI. The mortality rate was calculated according to each PESI risk class.

RESULTS

Of the 90 patients enrolled in this study, ten were assigned to PESI class I, 29 to PESI class II, 22 to PESI class III, eight to PESI class IV, and ten to PESI class V. The mortality rate after 30 days in each class was 0, 10.3, 9.1, 0, and 50% (p=0.0016), respectively, whereas the respective hospital mortality rate was 4.8, 13.8, 13.6, 12.5, and 50% (p=0.0065). The overall mortality was 9.5, 27.6, 31.8, 50.0, and 60%, respectively (p=0.0019). The mortality rate was significantly associated with the PESI class.

CONCLUSIONS

The PESI class was found to be significantly correlated with the 30-day mortality rate, hospital mortality, and overall mortality. Our data indicate that the PESI can be used to predict the prognosis of patients with pulmonary embolism and in making medical decisions regarding the treatment of patients with pulmonary embolism.

Outcome of thrombolysis for massive pulmonary embolism

BACKGROUND

Deep vein thrombosis is increasingly being diagnosed in Ghana. The commonest complication that leads to death is pulmonary embolism. The mortality rate from massive pulmonary embolism is high even with intervention. Thrombolysis is recommended in massive embolism.

OBJECTIVE

To determine the outcome of thrombolysis in the management of massive pulmonary embolism in patients admitted to the Cardiothoracic Intensive Care unit.

METHOD

A retrospective audit of the patients who were admitted to the Intensive care unit of the National Cardiothoracic centre with a diagnosis of massive pulmonary embolism between 1st January 2003 and 31st September 2007.

RESULTS

Seventeen patients were admitted with the diagnosis of massive pulmonary embolism of which 14 were thrombolysed. Commonest clinical presentations were dyspnoea in 17(100.0%) and hypotension in 12(70.3%) of the patients. Streptokinase was used in 13(92.9%) and urokinase in 1(7.1%) of the patients. The main complications of thrombolysis were bleeding in 12(85.7%), hypotension in 10(71.4%) and nausea and vomiting in 7(50.0%) of the patients. Postthrombolysis, the respiratory function deteriorated in 12 (85.7%) of the patients which required mechanical ventilation. The overall mortality rate was 35.3%. Three patients died before thrombolysis. Of the 14 (82.4%) who were thrombolysed 3(21.4%) died within 8 hours.

CONCLUSION

The mortality rate of patients with massive pulmonary embolism is high even after thrombolysis. The commonest complication of thrombolysis was bleeding.

Pulmonary and cerebral lipiodol embolism after transcatheter arterial hemoembolization in hepatocellular carcinoma

Pulmonary and cerebral lipiodol embolism after transcatheter arterial chemoembolization (TACE) of hepatocellular carcinoma is rare. To our knowledge, only 7 cases have been reported in the literature. We present a case of pulmonary and cerebral lipiodol embolism, and analyzed retrospectively the imaging and clinical data of the patient and conclude the most probable mechanism of pulmonary and cerebral lipiodol embolism, which is different from that of the cases reported previously.

Protein-losing enteropathy, deep venous thrombosis and pulmonary embolism in a patient with generalized inflammatory polyposis in remission stage of ulcerative colitis

We experienced a patient with severe protein-losing enteropathy and generalized inflammatory polyposis. In addition, this case was complicated by deep venous thrombosis and pulmonary embolism. Patients with inflammatory bowel disease are at increased risk for thromboembolic events, most commonly in the setting of active colitis. However, our patient was in the remission stage. We report the occurrence of deep venous thrombosis and pulmonary embolism as a complication of inflammatory polyposis and protein-losing enteropathy in the remission stage of ulcerative colitis.

A study of pulmonary embolism after abdominal surgery in patients undergoing prophylaxis

AIM: To determine risk factors for pulmonary embolism and estimate effects and benefits of prophylaxis.

METHODS: We included 78 patients who died subsequently to a pulmonary embolism after major abdominal surgery from 1985 to 2003. A first, retrospective analysis involved 41 patients who underwent elective surgery between 1985 and 1990 without receiving any prophylaxis. In the prospectively evaluated subgroup, 37 patients undergoing major surgery between 1991 and 2003 were enrolled: all of them had received a prophylaxis consisting in low-molecular weight heparin, given subcutaneously at a dose of 2850 IU AXa/0.3 mL (body weight < 50 kg) or 5700 IU AXa/0.6 mL (body weight ≥ 50 kg).

RESULTS: A higher incidence of thromboembolism (43.9% and 46.34% in the two groups, respectively) was found in older patients (> 60 years). The incidence of pulmonary embolism after major abdominal surgery in patients who had received the prophylaxis was significantly lower compared to the subjects with the same condition who had not received any prophylaxis (P < 0.001, OR = 2.825; 95% CI, 1.811-4.408). Furthermore, the incidence of pulmonary embolism after colorectal cancer surgery was significantly higher compared to incidence of pulmonary embolism after other abdominal surgical procedures. Finally, the incidence of pulmonary embolism after colorectal cancer surgery among the patients who had received the prophylaxis (11/4316, 0.26%) was significantly lower compared to subjects undergoing a surgical procedure for the same indication but without prophylaxis (10/1562, 0.64%) (P < 0.05, OR = 2.522; 95% CI, 1.069-5.949).

CONCLUSION: Prophylaxis with low molecular weight heparin is highly recommended during the preoperative period in patients with diagnosis of colorectal cancer due to high risk of pulmonary embolism after elective surgery.

Rare pulmonary and cerebral complications after transarterial chemoembolization for hepatocellular carcinoma: A case report

We report a rare case of acute pulmonary and cerebral complication after transarterial chemoembolization (TACE) for inoperable hepatocellular carcinoma. The case involved a large tumor and hepatic vein invasion. Nonspecific pulmonary and cerebral symptoms such as acute dyspnoea and transient consciousness loss developed in the patient, a 49-year-old woman, following the TACE due to pulmonary and cerebral oil embolism. The chest and brain conditions of this patient improved after some supportive therapies and nursing interventions. She also subsequently completed the other three procedures of TACE.

[Pulmonary hypertension and right ventricular failure in critical care medicine]

The management of pulmonary hypertension and right ventricular failure in hemodynamically unstable patients is one of the most challenging situations in critical care medicine. Inadequate therapy, e.g. aggressive fluid resuscitation or invasive ventilation, may even harm patients with pulmonary hypertension. Identifying the underlying etiology therefore remains the primary focus for initiating successful management of patients with decompensated pulmonary hypertension and right ventricular failure. Pulmonary embolism requires immediate restoration of pulmonary vascular patency. The body of evidence from studies is scarce and favors dobutamine, NO inhalation, and intravenous prostacyclin. However, the use of other vasoactive substances, inotropes, and supportive measures has been successful in individual patients; it should be guided by the expected effects on the pulmonary vasculature or right ventricle, and should be adapted to the patient's concomitant diseases.