Postoperative pulmonary embolism: timing, diagnosis, treatment, and outcomes

Transperineal drainage of prostate abscesses: A minimally invasive, low-risk management strategy that yields satisfactory results

Objectives

In this narrative review, we aim to present two cases of transperineal drainage of prostate abscesses with a good clinical outcome. Furthermore, we reviewed the literature on this treatment approach and aim to propose a minimally invasive protocol for managing this rare condition.

Patients and Methods

Our patients are 33- and 61-year-old males who both underwent uncomplicated transperineal drainage of prostate abscess with the use of a Precision Point device with rapid clinical improvement and complete resolution of the abscess within the follow-up period. We used PubMed to conduct a literature search and included and evaluated 16 relevant case reports and case series in which the authors utilized transperineal drainage techniques for prostatic abscesses.

Results

Our first patient was young and very unwell with sepsis and a pulmonary embolism. He had a complex abscess extending through the prostate to the left pelvic side wall. Trans-gluteal drainage of the pelvic side-wall collection was required in addition to transperineal drainage of the prostate abscess. After drainage and a prolonged course of antibiotics, he achieved resolution of the abscess by 7 weeks with ejaculatory function intact. Our second patient who was very keen on the preservation of ejaculatory function had multiple small abscesses and underwent transperineal drainage. He had significant interval improvement of his abscess burden at the 4-week follow-up and complete resolution at the 6-month follow-up. The total number of cases in the literature on our review is 22, with considerable variability in how the authors managed the prostate abscesses that underwent transperineal drainage, including variability in their follow-up time frame, choice of imaging modality, duration of antibiotic treatment, drain placement, and use of irrigation solutions (including antibiotics) into the abscess cavity. Furthermore, the sizes of the prostate abscesses were not consistently reported. Given the small sample size and variability in management from different authors, it was not possible to draw any statistical analysis.

Conclusion

Transperineal prostate abscess drainage combined with prolonged antibiotic therapy provides a less invasive alternative to treating prostate abscesses for those who which to preserve ejaculatory function and avoid the other adverse events of transurethral de-roofing. In itself, it can achieve complete resolution of abscess. It provides the benefit of drainage under real-time imaging; for percutaneous drain placement; prevents urethral injury; retrograde ejaculation; and can be done under local anaesthetic which is preferable for the unstable patient. The utility of the procedure may be limited by the complexity of the abscess or whether it has extended beyond the prostate. The patient should always be informed that further drainage via percutaneous methods or transurethral methods may be necessary if their clinical condition does not improve. We recommend this procedure be offered as an alternative to transurethral methods in younger patients and those who would like to preserve ejaculatory function. Furthermore, we highly encourage a prolonged course of antibiotic therapy and interval follow-up with clinical review of symptoms and imaging to confirm resolution.

Gone in 60 days: our first experience with a bioconvertible IVC filter

The Sentry bioconvertible IVC filter (Boston Scientific, MA, USA) contains a bioabsorbable filament which hydrolyses after 60 days, allowing the arms of the filter to spring open, retract into the vessel wall and endothelialise, leaving an unobstructed IVC lumen.

It is a novel treatment option for patients at transient risk of pulmonary emboli with a contraindication to anticoagulation. The device provides similar protection to other currently available devices against pulmonary emboli with minimal complications. It represents an effective alternative to retrievable filters, the removal of which is variously not attempted, not possible or associated with high complication rates.

We review the literature which underpins the development of the bioconvertible filter. We describe our first deployment of the filter in an 85-year-old female with gastric malignancy (who subsequently underwent a subtotal gastrectomy) with a history of anaemia and previous pulmonary emboli. The availability of a bioconvertible filter constitutes a further step forward in the management of patients with potential or active thromboembolic disease.

Impact of routine preoperative sonographic screening with early intervention for deep venous thrombosis in lower extremities on preventing postoperative venous thromboembolism in patients with gastric cancer scheduled for minimally invasive surgery

PURPOSE

This study aimed to investigate the clinical efficacy of lower-extremity ultrasonography screening with early intervention for deep venous thrombosis (DVT) on the incidence of venous thromboembolism (VTE) after minimally invasive surgery (MIS) for gastric cancer (GC).

METHODS

Between January 2012 and December 2019, 1070 patients were diagnosed with both clinical and pathological stage I-III GC and underwent MIS at our institution. Routine ultrasonographic screening for DVT in lower extremities is performed before MIS. Patients diagnosed with DVT were preoperatively administered anticoagulant therapy. Enoxaparin was routinely administrated after surgery irrespective of the presence of DVT. The incidence of postoperative symptomatic VTE was examined retrospectively.

RESULTS

A total of 74 (6.9%) patients were preoperatively diagnosed with DVT. Multivariate analyses revealed that age > 70 years (p = 0.015), female sex (p < 0.001), and positive serum D-dimer test (p < 0.001) were significant and independent risk factors for preoperative DVT. The incidence of symptomatic postoperative VTE was 1 (0.09%); symptomatic VTE developed in one patient among patients without DVT, whereas no patient with DVT developed VTE.

CONCLUSIONS

Preoperative DVT screening using lower-extremity ultrasonography followed by preoperative anticoagulant therapy should be considered as a useful strategy to safely perform MIS for GC without increasing the incidence of VTE.

Clinical course of venous thromboembolism following abdominally based microsurgical breast reconstruction: A case series

BACKGROUND

Venous thromboembolism (VTE) is a potentially devastating complication following abdominally based microsurgical breast reconstruction, with a reported incidence of 0.08-4%. The authors aim to describe disease presentation and clinical course following VTE diagnosis in patients within their practice.

METHODS

A retrospective chart review identified patients who underwent microsurgical breast reconstruction from January 2007 through December 2018. Patients with VTE diagnosed within 90 days of surgery were included. Demographics, co-morbidities, signs and symptoms, and characteristics of oncologic, surgical, and post-operative care were analyzed.

RESULTS

Seven hundred one patients underwent microsurgical breast reconstruction. Eleven patients with pulmonary embolism (PE) and four with deep vein thrombosis (DVT) were identified, resulting in VTE incidence of 2.1% (0.57% DVT, 1.6% PE). Patients were on average 51 years old and had an average body mass index (BMI) of 31.7 kg/m2. Two had a history of VTE, and none had a known hypercoagulable disorder. Using the 2005 Caprini model, all were high risk and seven were highest risk. Among those with PE, the most common symptom was shortness of breath, and the most common signs were desaturation or supplemental oxygen requirements. VTE was diagnosed on average 14.2 days post-operatively (range 2-52 days).

CONCLUSION

VTE is an infrequent complication following abdominally based microsurgical breast reconstruction. We recommend a high index of suspicion in women reporting shortness of breath or having desaturation, especially in those with high BMI, high Caprini scores, post-operative complications, or early return to the operating room.

The Clinical Rationale for the Sentry Bioconvertible Inferior Vena Cava Filter for the Prevention of Pulmonary Embolism

The Sentry inferior vena cava (IVC) filter is designed to provide temporary protection against pulmonary embolism (PE) during transient high-risk periods and then to bioconvert after 60 days after implantation. At the time of bioconversion, the device's nitinol arms retract from the filtering position into the caval wall. Subsequently, the stable stent-like nitinol frame is endothelialized. The Sentry bioconvertible IVC filter has been evaluated in a multicenter investigational-device-exemption pivotal trial (NCT01975090) of 129 patients with documented deep vein thrombosis (DVT) or PE, or at temporary risk of developing DVT or PE, and with contraindications to anticoagulation. Successful filter conversion was observed in 95.7% of patients at 6 months (110/115) and 96.4% at 12 months (106/110). Through 12 months, there were no cases of symptomatic PE. The rationale for development of the Sentry bioconvertible device includes the following considerations: (1) the period of highest risk of PE for the vast majority of patients occurs within the first 60 days after an index event, with most of the PEs occurring in the first 30 days; (2) the design of retrievable IVC filters to support their removal after a transitory high-PE-risk period has, in practice, been associated with insecure filter dynamics and time-dependent complications including tilting, fracture, embolization, migration, and IVC perforation; (3) most retrievable IVC filters are placed for temporary protection, but for a variety of reasons they are not removed in any more than half of implanted patients, and when removal is attempted, the procedure is not always successful even with advanced techniques; and (4) analysis of Medicare hospital data suggests that payment for the retrieval procedure does not routinely compensate for expense. The Sentry device is not intended for removal after bioconversion. In initial clinical use, complications have been limited. Long-term results for the Sentry bioconvertible IVC filter are anticipated soon.

Pulmonary Embolism After Endovascular Aortic Repair, a Retrospective Cohort Study

OBJECTIVES

Endovascular aortic repair (EVAR) is associated with an increased risk of pulmonary embolism, which is often clinically silent and therefore difficult to recognise. The aim was to investigate the incidence of pulmonary embolism after EVAR using routinely performed pre- and post-operative aortic computed tomography angiography (CTA), and the association between pulmonary embolism and mortality.

METHODS

This single centre retrospective cohort study included adult patients who underwent EVAR in the University Medical Centre Utrecht between January 2010 and July 2015 and who had a total aortic, thoracic aortic, or pulmonary CTA within one month post-operatively. Baseline and mortality data were obtained by reviewing hospital and general practitioner records. The primary outcome was pulmonary embolism within one month after surgery. Secondary outcomes were 30 day and six month mortality.

RESULTS

During the study period, 526 EVARs were performed. Seventy-four of these procedures were included in the analysis of which there were 40 thoracic and 34 abdominal EVARs. In nine patients (12%, 95% CI 7-22) pulmonary embolism was observed of which one was central, two were segmental, and six were subsegmental. Seven were clinically silent and two were present on the pre-operative CTA. Thirty day mortality was significantly higher in patients with pulmonary embolism (relative risk 14.4, 95% CI 1.4-143, p = .037) though none of the deaths seemed directly attributable to it.

CONCLUSIONS

This study, although preliminary, suggests that silent pulmonary embolism after EVAR occurs in approximately one in 10 patients, despite routine thrombo-embolism prophylaxis. Pulmonary embolism was associated with a higher 30 day mortality risk yet it was not the cause of death in any of these patients.

Sentry Bioconvertible Inferior Vena Cava Filter: Study of Stages of Incorporation in an Experimental Ovine Model

The Sentry inferior vena cava (IVC) filter is designed to provide temporary protection from pulmonary embolism (PE) and then bioconvert to become incorporated in the vessel wall, leaving a patent IVC lumen. Objective. To evaluate the performance and stages of incorporation of the Sentry IVC filter in an ovine model. Methods. Twenty-four bioconvertible devices and 1 control retrievable filter were implanted in the infrarenal IVC of 25 sheep, with extensive daily monitoring and intensive imaging. Vessels and devices were analyzed at early (≤98 days, n = 10) and late (180 ± 30 days, n = 14 study devices, 1 control) termination and necropsy time-points. Results. Deployment success was 100% with all devices confirmed in filtering configuration, there were no filter-related complications, and bioconversion was 100% at termination with vessels widely patent. By 98 days for all early-incorporation analysis animals, the stabilizing cylindrical part of the Sentry frame was incorporated in the vessel wall, and the filter arms were retracted. By 180 days for all late-incorporation analysis animals, the filter arms as well as frames were stably incorporated. Conclusions. Through 180 days, there were no filter-related complications, and the study devices were all bioconverted and stably incorporated, leaving all IVCs patent.

CT pulmonary angiography in lower limb arthroplasty

Aims

The aims of this study were to determine the indications and frequency of ordering a CT pulmonary angiography (CTPA) following primary arthroplasty of the hip and knee, and to determine the number of positive scans in these patients, the location of emboli and the outcome for patients undergoing CTPA.

Patients and Methods

We analyzed the use of CTPA, as an inpatient and up to 90 days as an outpatient, in a cohort of patients and reviewed the medical records and imaging for each patient undergoing CTPA.

Results

Out of 11 249 patients, scans were requested in 229 (2.04%) and 86 (38%) were positive. No patient undergoing CTPA died within 90 days. The rate of mortality from pulmonary embolism (PE) overall was 0.08%. CTPA was performed twice as often following total knee arthroplasty (TKA) compared with total hip arthroplasty (THA), and when performed was twice as likely to be positive. Hypoxia was the main indication for a scan, being the indication in 149 scans (65%); and in 23% (11 of 47), the PE was peripheral and unilateral. Three patients suffered complications resulting from therapeutic anticoagulation for possible PE, two of whom had a negative CTPA.

Conclusion

CTPA is more likely to be performed following TKA compared with THA. Hypoxia was the main presenting feature of PE. A quarter of PEs which were diagnosed were unilateral and peripheral. Further study may indicate which patients who have a PE after lower limb arthroplasty require treatment, and which can avoid the complications associated with anticoagulation. Cite this article: Bone Joint J 2018;100-B:938–44.

Detailed assessment of benefits and risks of retrievable inferior vena cava filters on patients with complicated injuries: the da Vinci multicentre randomised controlled trial study protocol

INTRODUCTION

Retrievable inferior vena cava (IVC) filters have been increasingly used in patients with major trauma who have contraindications to anticoagulant prophylaxis as a primary prophylactic measure against venous thromboembolism (VTE). The benefits, risks and cost-effectiveness of such strategy are uncertain.

METHODS AND ANALYSIS

Patients with major trauma, defined by an estimated Injury Severity Score >15, who have contraindications to anticoagulant VTE prophylaxis within 72 hours of hospitalisation to the study centre will be eligible for this randomised multicentre controlled trial. After obtaining consent from patients, or the persons responsible for the patients, study patients are randomly allocated to either control or IVC filter, within 72 hours of trauma admission, in a 1:1 ratio by permuted blocks stratified by study centre. The primary outcomes are (1) the composite endpoint of (A) pulmonary embolism (PE) as demonstrated by CT pulmonary angiography, high probability ventilation/perfusion scan, transoesophageal echocardiography (by showing clots within pulmonary arterial trunk), pulmonary angiography or postmortem examination during the same hospitalisation or 90-day after trauma whichever is earlier and (B) hospital mortality; and (2) the total cost of treatment including the costs of an IVC filter, total number of CT and ultrasound scans required, length of intensive care unit and hospital stay, procedures and drugs required to treat PE or complications related to the IVC filters. The study started in June 2015 and the final enrolment target is 240 patients. No interim analysis is planned; incidence of fatal PE is used as safety stopping rule for the trial.

ETHICS AND DISSEMINATION

Ethics approval was obtained in all four participating centres in Australia. Results of the main trial and each of the secondary endpoints will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ACTRN12614000963628; Pre-results.

Safety and Effectiveness of Enoxaparin as Venous Thromboembolism Prophylaxis after Gastric Cancer Surgery in Japanese Patients

Routine prophylaxis for venous thromboembolism (VTE) has been recommended after surgery not only in the West but also in Asia recently. The primary objective of this study was to investigate the safety and effectiveness of enoxaparin as a prophylaxis in patients undergoing distal, proximal, or total gastrectomy (TG) for gastric cancers. A total of 565 patients who underwent gastrectomy for gastric cancer were reviewed retrospectively. About 256 patients received postoperative prophylaxis with enoxaparin (2000 international unit twice daily for at least six days) and compression stockings; these patients were assigned to the enoxaparin group. About 257 patients comprised a historical control group, who used only compression stockings as a thromboprophylaxis. All patients underwent the same rehabilitation programs during the perioperative period. None of the patients developed symptomatic venous thromboembolism in either the enoxaparin group or the control group. The complication rate of bleeding was not significantly different between the two groups. Only one patient who used three antiplatelet agents concomitantly with enoxaparin required reoperation for anastomotic site bleeding. The usage of enoxaparin for venous thromboembolism prophylaxis is safe for Japanese patients after gastrectomy. But, cautious application is still needed especially when used concomitantly with other antiplatelet agents.

Timing of Symptomatic Pulmonary Embolism with Warfarin Following Arthroplasty

The purpose is to determine the incidence and timing of pulmonary embolism for patients receiving warfarin for thrombo-prophylaxis following total joint arthroplasty (TJA). Current guidelines for duration of prophylaxis are nonspecific. Chemical prophylaxis carries the risk of bleeding and associated periprosthetic joint infection. We retrospectively studied 26,415 primary and revision TJA cases performed at our institution between 2000 and 2010. The overall 90-day rate of symptomatic PE was 1.07%. Fatal PE rate was 0.02%. Out of 283 documented symptomatic PE cases, 81% occurred within three postoperative days, 89% within one postoperative week, and 94% within two postoperative weeks. The risk of symptomatic PE appears to be highest during the first week after TJA. Efforts must be made to minimize risk during this period.

Symptomatic pulmonary embolus after joint arthroplasty: stratification of risk factors

BACKGROUND

Prophylaxis for pulmonary embolism (PE) after total joint arthroplasty (TJA) presents the clinical dilemma of balancing the risk of postoperative thrombotic risk and anticoagulation-related complications such as bleeding, hematoma formation, and infection. Risk stratification of patients undergoing TJA is needed to tailor prophylaxis based on thrombotic and bleeding risk.

QUESTIONS/PURPOSES

The purpose of this study was to identify the preoperative comorbidities that were associated with an increased risk of symptomatic PE after joint arthroplasty in a large group of patients who had TJAs and who were treated with either aspirin or warfarin.

METHODS

We conducted a retrospective study of 26,391 primary and revision TJAs performed at our institution between January 2000 and April 2011. A total of 24,567 patients received warfarin prophylaxis for 6 weeks (targeted international normalized ratio of 1.5-2.0) and 1824 patients received 325 mg aspirin twice daily. Symptomatic patients with decreased oxygen saturation were evaluated for PE using either a ventilation/perfusion scan or multidetector CT scan. Symptomatic PEs occurring in patients within 90 days postoperatively identified with CT or ventilation/perfusion scans were considered complications related to surgery, and fatal PEs were those that occurred in patients who died during the hospital admission owing to cardiopulmonary failure after PE. Using a logistic regression analysis, a nomogram was created to predict postoperative symptomatic PE risk.

RESULTS

Risk of postoperative symptomatic PE after primary and revision TJAs was 1.1%. Risk of postoperative fatal PE was 0.02%. Elevated BMI (p < 0.035), procedures on the knee (p < 0.006), higher Charlson Comorbidity Index (p < 0.015), chronic obstructive pulmonary disorder (p = 0.006), atrial fibrillation (p < 0.001), anemia (p < 0.001), presence of deep vein thrombosis (p < 0.001), and depression (p = 0.012) were independent risk factors for symptomatic PE. Based on these risk factors and derived scoring criteria, patients can be classified into low- (0.35%), medium- (1.4%), and high- (9.3%) risk categories.

CONCLUSIONS

Patients who are obese, undergo knee procedures, have an elevated Charlson Comorbidity Index, chronic obstructive pulmonary disease, atrial fibrillation, anemia, depression, or postoperative deep vein thrombosis are at greater risk of having a postoperative PE develop. These risk factors should be considered when deciding on postoperative anticoagulation prophylaxis.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Incidence and risk factors for fatal pulmonary embolism after major trauma: a nested cohort study

BACKGROUND

Venous thromboembolism is common after major trauma. Strategies to prevent fatal pulmonary embolism (PE) are widely utilized, but the incidence and risk factors for fatal PE are poorly understood.

METHODS

Using linked data from the intensive care unit, trauma registry, Western Australian Death Registry, and post-mortem reports, the incidence and risk factors for fatal PE in a consecutive cohort of major trauma patients, admitted between 1994 and 2002, were assessed. Non-linear relationships between continuous predictors and risk of fatal PE were modelled by logistic regression.

RESULTS

Of the 971 consecutive trauma patients considered in the study, 134 (13.8%) died after their injuries. Fatal PE accounted for 11.9% of all deaths despite unfractionated heparin prophylaxis being used in 44% of these patients. Fatal PE occurred in those who were older (mean age 51- vs 37-yr-old, P=0.01), with more co-morbidities (Charlson's co-morbidity index 1.1 vs 0.2, P=0.01), had a larger BMI (31.8 vs 24.5, P=0.01), and less severe head and systemic injuries when compared with those who died of other causes. Sites of injuries were not significantly related to the risk of fatal PE. Fatal PE occurred much later than deaths from other causes (median 18 vs 2 days, P=0.01), and the estimated attributable mortality of PE was 49% (95% confidence interval 36-62%).

CONCLUSIONS

Fatal PE appeared to be a potential preventable cause of late mortality after major trauma. Severity of injuries, co-morbidity, and BMI were important risk factors for fatal PE after major trauma.