The Rate and Mortality of Postoperative Venous Thromboembolism of Moderate Risk Surgery in Asian Patients without Thrombo-prophylaxis: Systematic Review with Meta-analysis

Background

The general gynecologic and neurologic surgeries are regard as carrying moderate risk for postoperative venous thromboembolism (VTE). This review analyzed the postoperative VTE rate of these surgeries in Asia.

Methods

Inclusion criteria were: prospective study; deep vein thrombosis (DVT) diagnosed by venography, ultrasonography, or radionucleotide scan; and no thromboprophylaxis. The pooled proportion was back calculated from Freeman–Tukey variant transformation, using a random effect model.

Results

Medline, EMBASE, Cochrane Library, and KoreaMed were searched. Fourteen studies (total population of 1,625) published from 1974 to 2008 were included. In general surgery, the pooled rate of all-sites proximal, isolated distal DVT was 13.4, 2.1, and 11.8 % (radionucleotide scan). The cancer patients carried a higher all-sites DVT rate (19.7 % radionucleotide scan and 17.4 % ultrasound). Gynecologic and neurologic surgery had 3.1 % (ultrasound) and 3.8 % (radionucleotide scan) all-sites DVT rate. For general, gynecologic, and neurologic patients, the pooled rates of symptomatic DVT were 1.5, 0.2, and 1.0 % respectively. The pooled rate of symptomatic pulmonary embolism (PE) was 0.4 % for general surgery. No patients died from PE (pooled rate 0.2 %); however, a single PE death was reported in the excluded study.

Conclusions

Postoperative symptomatic VTE was relatively low in Asia. Further study is required to stratify VTE risk and the need for thromboprophylaxis in individual patients.     

Displaced inferior ramus fractures as a marker of posterior pelvic injury

Introduction

Injuries to the anterior or posterior pelvic ring rarely occur in isolation. Disruption to the anterior pelvic ring, indicated by a fracture of the superior or inferior pubic ramus, or injury to the pubic symphysis, may be indicative of additional pelvic ring disruption. The purpose of this retrospective study was to determine whether displaced inferior pubic ramus fractures warrant a more detailed investigation of the posterior ring in an effort to predict unstable posterior pelvic ring injuries.

Materials and methods

All patients with a displaced inferior ramus fracture on AP pelvic radiograph were identified at a single level I trauma center over a 5-year period. Complete pelvic radiographs and computed tomography scans were then evaluated for additional pelvic ring injuries. The data were analyzed using the chi-square test to determine the association between inferior ramus fractures and posterior pelvic ring injury.

Results

Sixty-three of the 93 patients with a fracture of the inferior ramus (68 %) were found to have a posterior ring injury; 60 % of these injuries were unstable. Patients with concurrent superior ramus fractures were more likely to have a posterior ring injury (p < 0.001) and an unstable pelvis (p = 0.018). Of those with a displaced unilateral inferior ramus fracture, parasymphyseal involvement was associated with higher incidence of posterior ring injury (p = 0.047) and pelvic instability (p = 0.028).

Conclusion

The anterior pelvic ring can be used to help identify unstable injuries to the posterior pelvis. Patients with displaced inferior pubic ramus fractures warrant a detailed examination of their posterior ring to identify additional injuries and instability.     

Angiographic embolization in the treatment of arterial pelvic hemorrhage: evaluation of prognostic mortality-related factors

Purpose

The control of arterial bleeding associated with pelvic ring and acetabular fractures (PRAF) remains a challenge for emergency trauma care. The aim of the present study was to uncover early prognostic mortality-related factors in PRAF-related arterial bleedings treated with transcatheter angiographic embolization (TAE).

Methods

Forty-nine PRAF patients (46 pelvic ring and three acetabular fractures) with arterial pelvic bleeding controlled with TAE (within 24 h) were evaluated.

Results

All large arterial disruptions (n = 7) were seen in type C pelvic ring injuries. The 30-day mortality in large vessel (iliac artery) bleeding was higher (57 %) than in medium- or small-size artery bleeding (24 %). Overall 30-day mortality was 29 %. No statistically significant difference in the first laboratory values between the survivors and nonsurvivors was found. However, after excluding patients dying of head injuries (n = 5), a reasonable cut-off value was identified for the base excess (BE; lower than ?10 mmol/l) obtained on admission.

Conclusions

PRAF patients with exsanguinating bleeding from the large pelvic artery have the worst prognosis. Very low BE values (<?10.0 mmol/l) on admission for exsanguinating patients have a negative predictive value for survival, thus anticipating a poor outcome in bleeding controlled with TAE only and an increased risk of death. In critical cases, an aggressive bleeding control protocol prompts extraperitoneal pelvic packing prior to TAE. PRAF-related rupture of the external iliac artery is rare and indicates surgical techniques in controlling and restoring blood supply to the lower leg.     

Posterior bridging osteosynthesis for traumatic sacroiliac joint dislocation: a report of seven cases

Objective

To evaluate the long-term clinical and radiographic results in patients treated for 61C3-2 (OTA class) pelvic ring disruption with a posterior bridging sacroiliac fixation.

Design

Retrospective clinical and radiological study.

Setting

University Hospital.

Patients/participants

Between May 2002 and March 2003, seven patients with sacroiliac dislocation were treated with a technique developed for the treatment of pelvic injuries with vertical and horizontal instability.

Intervention

We applied spino-pelvic fixation techniques, using spine instrumentation, to stabilize an SI dislocation. This technique consists of two 5 mm diameter screws inserted into the S1 pedicle and S2 ala. A 5.5 mm rod joins the 2 sacral screws to two 7 mm screws placed into the posterior iliac crest and secured into the cancellous mass of the posterior ilium . The described technique stabilizes the SI-joint by performing a bridging osteosynthesis instead of the commonly performed iliosacral screw osteosynthesis passing the SI-joint. Symphyseal platting is performed to reduce and stabilize the anterior ring if necessary.

Main outcome measurements

Data were analyzed as follows: pelvic fracture classification; functional outcome; radiographic outcome; Leg length discrapency; and CT scan aspect of the sacroiliac joint.

Results

Associated pelvic injuries were present in all the patients and include symphysis rupture and acetabular fractures. Four of the seven patients had fractures of the lower extremities. Follow-up was available for all patients at an average of 27 months (range, 32–24 months). Neither septic nor cutaneous complications were reported. No loss of post-op reduction and no fixation failure were observed. The functional results noted at the last examination were satisfactory with a mean Majeed score of 93.

Conclusion

In our opinion, this surgical technique may be indicated in Tile type C1.2 (61C3-2 OTA class) pelvic ring disruption. It obviously reaches its limits in sacral fractures. The technique described provides effective control of vertical displacement while providing a certain degree of horizontal mobility to facilitate reduction and osteosynthesis of anterior lesions. The quality of the fixation allowed early weight bearing.     

Symptomatic venous thromboembolism in Asian major trauma patients: incidence, presentation and risk factors

Background

Trauma patients are known to be at increased risk of venous thromboembolism (VTE), and pulmonary embolism (PE) is one of the preventable causes of mortality in trauma patients. The incidence of VTE in Asian populations was believed to be lower than in Caucasians, but the recent literature suggests that this is not the case. The purpose of this study was to assess the incidence of VTE in Asian major trauma patients and to examine the manner of presentation, use of prophylaxis and risk factors for VTE. While other studies of VTE have addressed general and high-risk populations within Asia, our study is one of the few to examine Asian major trauma patients.

Methods

Data for all patients with VTE were extracted from the Singapore General Hospital trauma database over a 10-year period from 1998 to 2007. Patient profiles and clinical factors were compared to patients without a diagnosis of VTE admitted with injuries in the same time period.

Results

There were 8,615 patients entered into our database in this 10-year period. Thirty-four patients had VTE, with an overall incidence of 0.39 %. Thirteen patients had pulmonary embolism, an incidence of 0.15 %. Of note, 30 % of patients with deep vein thrombosis (DVT) presented with fever alone without limb symptoms. Almost all 34 patients who developed VTE had either head injury, a spinal cord injury or a pelvic/extremity injury. Eighteen patients had head injury, 22 patients sustained pelvic or extremity injury, and three patients had spinal cord injury with paraplegia. Head injury and spinal cord injury with neurologic sequelae were statistically significant risk factors for VTE (p < 0.05).

Conclusion

The incidence of symptomatic VTE in the Asian trauma population is no lower than in the West. The incidence found in this study is similar to the incidence of VTE according to a study using data from the American national trauma data bank using similar study methods and with a similar study population. It is also higher than the incidence in the literature for general post-surgical Asian patients. Fever was the presenting factor in some patients and screening for VTE should not be forgotten when assessing fever in the trauma patient. The strong association between head injury, spinal cord injury and VTE confirms that we should pay special attention to VTE prophylaxis for our patients with these injuries.     

Modulare Defektrekonstruktion beim Pfannenwechsel mit Abstützschale und metallischen Augmenten

Objective

Restore primary center of rotation and reconstruct extensive bone defects in hip revision surgery with a modular off-label implant combined with antiprotrusion cage and metal augment, thus, achieving improved hip function.

Indications

Large segmental acetabular defects with nonsupportive columns (Paprosky type 3a and 3b) in cup loosening or Girdlestone situation. In case of pelvic discontinuity posterior column-plating is possible.

Contraindications

Persisting hip infection and severe systemic disorders impairing achievement of secondary stability through bony integration of metal augment.

Surgical technique

Posterolateral (if dorsal column plating) or other approach. Remove loose implant and granulation tissue with sufficient exposure of bleeding bone. Size acetabular defect with trial components of augment and appropriate antiprotrusio cage. Fixation of selected metal augment with screws. Fill additional acetabular defects with morsellized bone graft. Open a slot into the ischium to fix the distal flange of the cage. If necessary, bend both flanges according to patient’s anatomy. Enter the ischium with distal flange and gradual impaction of the antiprotrusio ring. Final stabilization of the ring with several screws aiming at the posterior column or the acetabular dome. Inject cement between ring and augment to stabilize the construction and avoid metal wear. Final cement fixation of a polyethylene liner or a dual-mobility cup into the antiprotrusio ring. In pelvic discontinuity with major instability osteosynthesis of the dorsal column can be performed prior to cementation.

Postoperative management

Prophylaxis of periprosthetic infection, DVT and heterotopic ossification. Physical therapy with partial weight bearing (20 kp) for 6 weeks; in discontinuity initial wheel chair mobilization.

Results

Since 2008, 72 off-label implantations of a combined antiprotrusio cage and a Trabecular Metal? Augment were performed. A total of 44 patients (46 operations) were investigated at 38.8 (36–51) months postoperatively. In all, 36 patients had a bone defect according to Paprosky type 3a/b and in 3/4 patients with pelvic discontinuity additional osteosynthesis was performed. The WOMAC score increased from 39.8 (8.7–75) points preoperatively to 57.9 (16.7–97.9) points at follow-up. Migration or failure of implant components was not observed. In 11?% of dislocations and 11?% periprosthetic infections surgical revision was necessary.     

The anterior subcutaneous internal fixator (ASIF) for unstable pelvic ring fractures. Clinical and radiological mid-term results

Purpose

The purpose of this study was to determine the outcome of unstable type C pelvic fractures treated with posterior stabilisation and the anterior subcutaneous internal fixator (ASIF).

Methods

Altogether, 36 consecutive patients were treated for unstable type C pelvic ring fractures using posterior stabilisation and ASIF. After a minimum of 18 months, the clinical and radiological outcome was retrospectively investigated.

Results

Overall, three patients (8.3 %) died, and 31 patients (86 %) were available for follow-up after a mean of 4.5 years. Thirty of 31 patients (97 %) showed radiographic bone consolidation of both the posterior and anterior pelvic ring. Only one non-union and two infections due to the anterior device were observed. The total German pelvic outcome score showed an excellent or good rating for 64.5 % of the patients, and a fair or poor for 35.5 %. The SF-12 questionnaire showed a significantly reduced total score for physical and mental health compared to a general reference population.

Conclusions

The ASIF represents an innovative surgical procedure for the treatment of type C pelvic ring fractures. In the medium term, patient satisfaction was high and the complication rate was low, despite the small number of patients. More cases must be investigated before the procedure can be recommended in general, possibly replacing the external fixator for the treatment of pelvic ring fractures in the future.     

Management of severe periacetabular bone loss combined with pelvic discontinuity in revision hip arthroplasty

Purpose

Revision of failed total hip arthroplasty with massive acetabular bone loss resulting in pelvic discontinuity represents a rare but challenging problem. The objective of this study was to present short to mid-term results of revision total hip arthroplasty with a custom-made acetabular implant in a consecutive series of patients with pelvic discontinuity.

Methods

We retrospectively reviewed 18 consecutive patients with massive acetabular bone loss (Paprosky Type 3B) resulting in pelvic discontinuity reconstructed with revision total hip arthroplasty using a custom-made acetabular component. The prosthesis was created on the basis of a thin-cut 1-mm computed tomography (CT) scan of the pelvis. Initial stability of the implant was obtained by screw fixation. Harris hip score and sequential radiographs were used to evaluate the clinical and radiographic results.

Results

At an average follow up of 30 months (range 17–62 months) 16 of 18 (88.9 %) custom-made implants were considered radiographically stable without signs of acetabular migration of more than 2 mm in the horizontal or vertical direction, implant rotation or screw breakage. Complications included two periprosthetic joint infections treated with explantation of the implant. Three patients had recurrent dislocations postoperatively. The mean Harris hip score improved from 28?±?12 points preoperatively to 69?±?13 points at the time of last follow up.

Conclusion

Treatment of acetabular bone loss and pelvic discontinuity with a custom-made acetabular component can provide a durable solution with good clinical and radiographic results.     

Pelvic Tilt Is Minimally Changed by Total Hip Arthroplasty

Background

While surgical navigation offers the opportunity to accurately place an acetabular component, questions remain as to the best goal for acetabular component positioning in individual patients. Overall functional orientation of the pelvis after surgery is one of the most important variables for the surgeon to consider when determining the proper goal for acetabular component orientation.

Questions/Purposes

We measured the variation in pelvic tilt in 30 patients before THA and the effect of THA on pelvic tilt in the same patients more than a year after THA.

Methods

Each patient had a CT study for CT-based surgical navigation and standing and supine radiographs before and after surgery. Pelvic tilt was calculated for each of the radiographs using a novel and validated two-dimensional/three-dimensional matching technique.

Results

Mean supine pelvic tilt changed less than 2°, from 4.4° ± 6.4° (range, ?7.7° to 20.8°) before THA to 6.3° ± 6.6° (range, ?5.7° to 19.6°) after THA. Mean standing pelvic tilt changed less than 1°, from 1.5° ± 7.2° (range, ?13.1° to 12.8°) before THA to 2.0° ± 8.3° (range, ?12.3° to 16.8°) after THA. Preoperative pelvic tilt correlated with postoperative tilt in both the supine (r² = 0.75) and standing (r² = 0.87) positions.

Conclusions

In this population, pelvic tilt had a small and predictable change after surgery. However, intersubject variability of pelvic tilt was high, suggesting preoperative pelvic tilt should be considered when determining desired acetabular component positioning on a patient-specific basis.     

Significance of Computed Tomography Finding of Intra-Abdominal Free Fluid Without Solid Organ Injury after Blunt Abdominal Trauma: Time for Laparotomy on Demand

Background

Optimal management of patients with intra-abdominal free fluid found on computed tomography (CT) scan without solid organ injury remains controversial.

Objective

The purpose of this study was to determine the significance of CT scan findings of free fluid in the management of blunt abdominal trauma patients who otherwise have no indications for laparotomy.

Methods

During the 3-year study period, all patients presenting with blunt abdominal trauma who underwent abdominal CT examination were retrospectively reviewed. All hemodynamically stable patients who presented with abdominal free fluid without solid organ injury on CT scan were analyzed for radiological interpretation, clinical management, operative findings, and outcome.

Results

A total of 122 patients were included in the study, 91 % of whom were males. The mean age of the patients was 33 ± 12 years. A total of 34 patients underwent exploratory laparotomy, 31 of whom had therapeutic interventions. Small bowel injuries were found in 12 patients, large bowel injuries in ten, and mesenteric injuries in seven patients. One patient had combined small and large bowel injury, and one had traumatic gangrenous appendix. In the remaining three patients, laparotomy was non-therapeutic. A total of 36 patients had associated pelvic fractures and 33 had multiple lumbar transverse process fractures.

Conclusion

Detection of intra-peritoneal fluid by CT scan is inaccurate for prediction of bowel injury or need for surgery. However, the correlation between CT scan findings and clinical course is important for optimal diagnosis of bowel and mesenteric injuries.     

Is routine chemoprophylaxis necessary for prevention of venous thromboembolism following knee arthroplasty in a low incidence population?

Background

Standard thromboprophylaxis guidelines have not been applied universally in regions with low incidence of deep-vein thrombosis (DVT) considering risks of chemoprophylaxis and low incidence itself. We evaluated the prevalence of DVT, efficacy and safety of chemoprophylaxis, and necessity of pharmacological prevention in a low DVT incidence population.

Methods

One hundred and forty-eight patients undergoing unilateral total knee arthroplasty (TKA) were prospectively randomized to receive either a placebo or 2.5 mg of fondaparinux once daily for 5 days. Doppler ultrasonography was performed preoperatively and 7 days after surgery. The primary efficacy outcome was prevalence of DVT up to day 7. Secondary efficacy outcome was prevalence of symptomatic venous thromboembolism (VTE) up to day 90. Primary and secondary safety outcomes were incidence of major and minor bleeding, respectively.

Results

The prevalence of total DVT was 25.7 % in placebo group and 6.8 % in fondaparinux group (p = 0.002) and the prevalence of proximal DVT was lower in both groups with no statistical difference. There was no symptomatic VTE in either group up to day 90. Although no major bleeding was developed, fondaparinux group had a significant increase of minor bleeding events (p < 0.001).

Conclusions

There remains low incidence of VTE following TKA in East Asians even without chemoprophylaxis. Although short-term fondaparinux protocol could reduce the incidence of overall DVT, its routine use seems debatable due to extremely rare proximal DVT and symptomatic PE and drug-related bleeding complication. However, modified and selective use of chemoprophylaxis would be considerable in high risk patients.     

Pulmonary Embolism and Deep Venous Thrombosis Following Bariatric Surgery

Background

The contribution of obesity to the thromboembolic risks of surgery suggests that patients undergoing bariatric surgery would have a particularly high risk of postoperative pulmonary embolism (PE) and/or deep venous thrombosis (DVT). This study aimed to assess the prevalence of in-hospital PE, DVT, and venous thromboembolism (VTE) following bariatric surgery in the USA from 2007 to 2009.

Methods

We used the database of the Nationwide Inpatient Sample.

Results

The prevalence of PE was 4,500 of 508,230 (0.9 %). The prevalence of DVT not accompanied by PE was 6,480 of 508,230 (1.3 %) and VTE (either PE or DVT) occurred in 10,980 of 508,230 (2.2 %). In-hospital death among patients with PE was 130 of 508,231 (0.03 %). Vena cava filters were inserted in 1,515 of 508,230 (0.3 %) patients who underwent bariatric surgery. Among patients who had VTE, filters were inserted in 1,150 of 10,980 (10.5 %). Among patients who had neither PE nor DVT, prophylactic vena cava filters were inserted in 365 of 497,250 (0.07 %). Among patients with PE, in-hospital mortality was 25 of 635 (3.9 %) with a filter compared with 105 of 3,865 (2.7 %) (NS) without a filter. However, among patients with DVT alone, in-hospital mortality was 0 of 510 (0 %) with a filter compared with 80 of 5,970 (1.3 %) (P?=?0.009) without a filter.

Conclusions

This investigation establishes a baseline for the incidence of venous thromboembolic complications following bariatric surgery in recent years. Determination of the present in-hospital rate of PE and DVT may contribute to antithrombotic prophylactic considerations.     

Outpatients thromboprophylaxis following lower limb immobilisation: an institution’s experience

Background

Thromboembolism is a recognised preventable complication following lower limb immobilisation. This study evaluates an institution's experience of outpatient Venous Thromboembolism (VTE) prophylaxis using either Dalteparin administered subcutaneously or off-license Dabigatran orally in patients with lower limb injury requiring immobilisation.

Method

Group I consisted of 383 patients who were given either Dalteparin subcutaneously (239) or off-license Dabigatran (128) VTE prophylaxis orally following lower limb injury requiring immobilisation with 15 patients declined either option. Group II consisted of 679 patients that did not receive any thromboprophylaxis following lower limb injury requiring immobilisation. Clinical identifiable Pulmonary Embolism (PE) and Deep Vein Thrombosis (DVT) were extracted from the prospective VTE database and electronic patient records for Group I. While for Group II, this was information was obtained from patient’s records (retrospectively).

Results

There was no significant difference (Fisher's exact test) between Group I and Group II for DVT (0.168) and PE (0.284). The clinical PE and DVT incidence rate in Group I was 0.5 and 0 %, respectively, while in Group II, it was 0.1 and 0.7 %, respectively. One patient developed haemoptysis after Dabigatran was administered orally, and one patient had gastrointestinal bleeding after Dalteparin was given subcutaneously; no adverse medical harm came to either patient.

Conclusion

Although this study was unable to demonstrate, a statistically significant impact on VTE rates with prophylaxis, the protective role of prophylaxis is suggested by the low incidence of VTE in our study population, which is comparable to literature (20 %).

Level of Evidence: Therapeutic Level III

     

Defining Incidence and Risk Factors of Venous Thromboemolism after Hepatectomy

Background

The incidence of venous thromboembolism (VTE) among patients undergoing hepatic surgery is poorly defined, leading to varied use of VTE prophylaxis among surgeons. We sought to define the incidence of VTE after liver surgery and identify risk factors associated with VTE.

Methods

Incidence of VTE and associated risk factors within 90 days of hepatic resection between 2006 and 2012 at a major academic center was analyzed. Risk factors for VTE were identified using univariate and multivariate analyses.

Results

A total of 599 patients were included in the study cohort; 30 (5.0 %) had a prior history of VTE. The indications for surgery were malignant (90.8 %) and benign lesions (9.2 %). The majority of patients underwent a minor hepatectomy (<3 Couinaud segments; n?=?402, 67.1 %) while 195 (32.6 %) patients underwent a major hepatectomy (≥3 Couinaud segments). Three hundred seven (51.3 %) patients were started on VTE chemoprophylaxis preoperatively with 407 (67.8 %) patients receiving VTE chemoprophylaxis within 24 h of surgery. Twenty-eight (4.7 %) patients developed VTE; 20 (3.3 %) had deep venous thrombosis (DVT), 11 (1.8 %) had pulmonary embolism (PE), and three (0.5 %) developed both DVT and PE. Among the VTE patients, 23 (82.1 %) had received VTE chemoprophylaxis. On multivariate analyses, history of VTE (odds ratio [OR] 4.51, 95 % confidence interval [CI] 1.81–17.22, P?=?0.03), prolonged operative time (OR 1.17 per additional hour, 95 % CI 1.04–1.32, P?=?0.009), and increased length of stay (LOS) (OR 1.07, 95 % CI 1.02–1.12, P?=?0.01) were independent risk factors for VTE.

Conclusion

VTE within 90 days of hepatic resection is common, occurring in nearly one in 20 patients. Most VTE events occurred among patients who received current best practice prophylaxis for VTE. More aggressive strategies to identify and reduce the risk of VTE in patients at highest risk of VTE, including those with a history of VTE, extended operative time, and prolonged LOS, are warranted.     

Newly modified Stoppa approach for acetabular fractures

Purpose

We present our experience of using a newly modified Stoppa approach combined with a lateral approach to the iliac crest in patients with acetabular fractures in reference to fracture reduction and fixation, technical aspects, and the incidence of complications.

Methods

We used a consecutive group of 29 adult patients with acetabular fractures treated operatively with a newly modified Stoppa approach between 2009 and 2011. The newly modified Stoppa approach was performed to fix the acetabular fractures with main anterior displacement and the anterior and lateral parts of the pelvis. This approach was combined with a lateral approach on the iliac crest for fractures of the iliac wing.

Results

All the patients were followed up for at least 1.5 years. Of the 29 patients, ten anterior column, two associated both column, seven anterior column with posterior hemi-transverse, four transverse, and six T-type fractures. The average blood loss was 950 mL, and average operative time was 155 minutes. Anatomic or satisfactory reduction was achieved in 96 % of the acetabular fractures. Two patients had mild symptoms of the lateral femoral cutaneous nerve and improved within three months.

Conclusions

The newly modified Stoppa approach provides excellent visualization to the anterior column, quadrilateral surface and permits good postoperative results for treatment of acetabular fractures. We considered this technique as a viable alternative for the ilioinguinal approach when exposure of the anterior acetabulum is needed.     

Retrievable inferior vena cava filters in high-risk patients undergoing bariatric surgery

Background

Placement of retrievable inferior vena cava filters (rIVCF) may be beneficial in high-risk morbidly obese patients undergoing bariatric procedures. Patients with a previous history of venous thromboembolism (VTE) are at high risk for postoperative deep venous thrombosis (DVT) and pulmonary embolism (PE).

Methods

A prospective database of bariatric surgery patients was studied from April 2003 to May 2007. A total of 791 patients underwent bariatric procedures, of which 30 (4%) had a previous history of VTE. These patients underwent preoperative venous duplex and concurrent placement of a rIVCF. Patient demographics and clinical outcomes were examined.

Results

Thirty patients (12 (40%) men) had a mean age of 49 ± 8 years and a mean body mass index of 50 ± 8 kg/m². Sixteen patients (53%) underwent laparoscopic Roux-en-Y gastric bypass, ten (33%) underwent laparoscopic adjustable gastric band, and four (14%) underwent open Roux-en-Y gastric bypass. Mean operative time, including rIVCF placement, was 162 ± 66 minutes. All patients had successful rIVCF placement with standard perioperative chemoprophylaxis. Twenty-nine patients (97%) had a follow-up ultrasound on postoperative day (POD) 19 ± 25. Six patients (21%) had recurrent DVT. Twenty-seven patients (90%) underwent a follow-up venogram, and four patients (15%) had significant thrombus in the rIVCF. Retrieval was successful in 21 patients (70%). Nine patients (30%) did not undergo retrieval: four had significant thrombus in the filter, four had an above-knee DVT, and one due to technical reasons. We observed one complication with a DVT at the access site and no PE or mortality.

Conclusions

We observed a 21% incidence of recurrent DVT and 15% incidence of thrombus in the IVCF, yet no PE occurred. IVCF retrieval was successful in 70% with one complication. Concurrent IVCF placement is safe, feasible, and an effective preventative measure in high-risk morbidly obese patients. We recommend the use of rIVCFs in conjunction with standard VTE prophylaxis in this patient population.     

Accuracy of screw fixation using the O-arm<Superscript>®</Superscript> and StealthStation<Superscript>®</Superscript> navigation system for unstable pelvic ring fractures

Purpose

Screw fixation for unstable pelvic ring fractures is generally performed using the C-arm. However, some studies reported erroneous piercing with screws, nerve injuries, and vessel injuries. Recent studies have reported the efficacy of screw fixations using navigation systems. The purpose of this retrospective study was to investigate the accuracy of screw fixation using the O-arm^® imaging system and StealthStation^® navigation system for unstable pelvic ring fractures.

Methods

The participants were 10 patients with unstable pelvic ring fractures, who underwent screw fixations using the O-arm StealthStation navigation system (nine cases with iliosacral screw and one case with lateral compression screw). We investigated operation duration, bleeding during operation, the presence of complications during operation, and the presence of cortical bone perforation by the screws based on postoperative CT scan images. We also measured the difference in screw tip positions between intraoperative navigation screen shot images and postoperative CT scan images.

Results

The average operation duration was 71 min, average bleeding was 12 ml, and there were no nerve or vessel injuries during the operation. There was no cortical bone perforation by the screws. The average difference between intraoperative navigation images and postoperative CT images was 2.5 ± 0.9 mm, for all 18 screws used in this study.

Conclusion

Our results suggest that the O-arm StealthStation navigation system provides accurate screw fixation for unstable pelvic ring fractures.

     

Incidence of symptomatic venous thrombo-embolism following shoulder surgery

Purpose

This clinical study was performed to establish the incidence of symptomatic deep vein thrombosis and pulmonary embolism after shoulder surgery as the incidence of venous thrombo-embolism complicating shoulder surgery is poorly described in literature.

Methods

We reviewed retrospectively clinical records of 920 consecutive patients who had any surgical procedure performed on their shoulder in Glan Clwyd Hospital, North Wales and a further 1,421 consecutive patients who had surgery in Morriston and Singleton Hospitals, South Wales. Patients’ records were assessed for any admissions due to proven VTE; we investigated for any radiological results suggestive of venous thrombo-embolism and for deaths in the post-operative period.

Results

We analyzed data of 2,341 patients. There was one fatal PE in this group, whereby the patient died within 48 hours following reverse shoulder replacement, and post mortem revealed massive pulmonary embolism. There were a further three cases of symptomatic, non-fatal PE. There were six cases of symptomatic DVT of lower limb. All these cases were treated successfully with anticoagulation. No upper limb DVT was identified.

Conclusion

Recent studies suggest that DVT prevalence following shoulder arthroplasty is as high as 13 %. In our study we examined occurrence of symptomatic VTE only. According to our results the prevalence of symptomatic DVT following shoulder surgery is 0.26 %, symptomatic PE 0.17 % and combined prevalence of VTE is 0.43 %. We would advise careful thought about the risk of thrombosis and use mechanical prophylaxis in shoulder surgery, especially for longer procedures. We would not recommend routine pharmacological prophylaxis unless there are additional risk factors.