Background and purpose: The appropriate fixation method for
hemiarthroplasty of the hip as it relates to implant survivorship and patient mortality is a matter of ongoing debate. We examined the influence of fixation method on revision rate and mortality.----- -----
Methods: We analyzed approximately 25,000 hemiarthroplasty
cases from the AOA National Joint Replacement Registry. Deaths at 1 day, 1 week, 1 month, and 1 year were compared for all patients and among subgroups based on implant type.----- -----
Results: Patients treated with cemented monoblock hemiarthroplasty had a 1.7-times higher day-1 mortality compared to uncemented monoblock components (p < 0.001). This finding was reversed by 1 week, 1 month, and 1 year after surgery (p < 0.001). Modular hemiarthroplasties did not reveal a difference in mortality between fixation methods at any time point.----- -----
Interpretation: This study shows lower (or similar) overall
mortality with cemented hemiarthroplasty of the hip.

Perioperative mortality after hemiarthroplasty related to fixation method : a study based on the Australian Orthopaedic Association National Joint Replacement Registry

Bone cement implantation syndrome (BCIS) is poorly understood. It is an important cause of intraoperative mortality and morbidity in patients undergoing cemented hip arthroplasty and may also be seen in the postoperative period in a milder form causing hypoxia and confusion. Hip arthroplasty is becoming more common in an ageing population. The older patient may have co-existing pathologies which can increase the likelihood of developing BCIS. This article reviews the definition, incidence, clinical features, risk factors, aetiology, pathophysiology, risk reduction, and management of BCIS. It is possible to identify high risk groups of patients in which avoidable morbidity and mortality may be minimized by surgical selection for uncemented arthroplasty. Invasive anaesthetic monitoring should be considered during cemented arthroplasty in high risk patients.

/pdf/bone-cement-implantation-syndrome-49fn8exemk.pdf

Bone cement implantation syndrome

Study Design.A prospective in vivo study was conducted during the performance of kyphoplasty for the treatment of osteoporotic vertebral compression fractures, comparing extravertebral contrast extravasation with kyphoplasty and vertebroplasty.Objective.To determine the frequency and pattern of extr

http://ossano.com/Bibliotek/VerteKyphoPlastik/L08%20Phillips.pdf

An in vivo comparison of the potential for extravertebral cement leak after vertebroplasty and kyphoplasty.

The records of 23 patients who died intraoperatively during hip arthroplasty at the authors' institution were reviewed. Of the 38,488 hip arthroplasties in 29,431 patients performed between 1969 and 1997, there were 23 deaths during surgery. There were 15 women and eight men with a mean age of 80.9 years. Preoperative diagnoses were acute hip fracture (13 patients), pathologic fracture (four patients), femoral neck nonunion (one patient), osteoarthritis (four patients), and rheumatoid arthritis (one patient). Eleven patients undergoing cemented total hip arthroplasty died and 12 patients undergoing cemented hemiarthroplasty died. All deaths occurred because of irreversible cardiorespiratory disturbances that were initiated during cementing. There were no deaths among 12,551 patients receiving 15,411 uncemented hip arthroplasties during the 28-year period under review. Autopsy was performed in 13 patients. Bone marrow microemboli were seen in the lungs of 11 of 13 patients in whom an autopsy was performed and methylmethacrylate particles were seen in the lungs of three of 13 patients. These data suggest that elderly patients with preexisting cardiovascular conditions undergoing cemented arthroplasty, especially for fracture diagnosis, are at increased risk for intraoperative death compared with patients undergoing elective hip arthroplasty. In the latter years of the current study, modifications of the operative techniques designed to minimize intramedullary hypertension were associated with a reduction greater than three-fold in overall intraoperative mortality rate. These changes in surgical technique should be considered when cement fixation is used in patients thought to be at risk for having cardiopulmonary disturbances develop from venous embolization of marrow contents.

Sudden Death During Primary Hip Arthroplasty

Fat embolism: Fat embolism

An experimental model was designed to investigate the role of intramedullary pressure on cardiopulmonary function and pulmonary pathology during arthroplasty using cemented and non-cemented components. Twenty-four dogs were divided randomly into three groups: a group that received a non-cemented implant in which low intramedullary pressure was generated, a group that received a cemented implant, and one that received bone wax and an implant; high intramedullary pressures were generated in the latter two groups. Bone wax was used to generate high intramedullary pressures without the use of bone cement. In the group with the non-cemented implant, few pulmonary microemboli and no significant cardiorespiratory changes were found. In the groups that received bone wax and an implant or the cemented implant, there were many pulmonary microemboli and significant cardiorespiratory changes, including decreased arterial oxygen tension, increased pulmonary arterial pressure, and increased intrapulmonary shunt fraction. There was no evidence that methylmethacrylate monomer was responsible for the cardiorespiratory changes in the group with the cemented implant.

Cardiopulmonary function and pulmonary microemboli during arthroplasty using cemented or non-cemented components. The role of intramedullary pressure.

To determine the efficacy of high-volume, high-pressure pulsatile lavage in the prevention of cardiopulmonary dysfunction and fat embolism during cemented arthroplasty, we studied twenty-eight mongrel dogs that had had a bilateral cemented arthroplasty. Significant increases in pulmonary-artery pressure and pulmonary vascular resistance, accompanied by decreases in arterial oxygen tension and increases in intrapulmonary shunt fraction (Qs/Qt), characterized cardiopulmonary dysfunction after bilateral cemented arthroplasty when no lavage was used. Low-volume, low-pressure manual lavage did not significantly alter these physiological changes, but there was a significant reduction in the number of fat emboli that were demonstrated in the lungs as compared with the no-lavage group. High-volume, high-pressure pulsatile lavage of the intramedullary cavity after reaming significantly reduced the changes in pulmonary-artery pressure, pulmonary vascular resistance, arterial oxygen tension, and intrapulmonary shunt fraction (Qs/Qt). In the pulsatile-lavage group, the number of fat microemboli that were found in the lungs was reduced to 25.7 per cent of those found in the no-lavage group. We concluded that meticulous high-volume, high-pressure pulsatile lavage reduces both pulmonary physiological derangements and fat emboli during bilateral cemented arthroplasty in dogs.

High-volume, high-pressure pulsatile lavage during cemented arthroplasty.

An episode of hypotension is common during cemented joint replacement, and has been associated with circulatory collapse and sudden death. We studied the mechanism of hypotension in two groups of six dogs after simulated bilateral cemented arthroplasty. In one group, with no lavage, the insertion of cement and prosthesis was followed by severe hypotension, elevated pulmonary artery pressure, decreased systemic vascular resistance and a 21% reduction in cardiac output. In the other group, pulsatile intramedullary lavage was performed before the simulated arthroplasties. Hypotension was less, and although systemic vascular resistance decreased, the cardiac output did not change. The severity of the hypotension, the decrease in cardiac output and an increase in prostaglandin metabolites were related to the magnitude of pulmonary fat embolism. Pulsatile lavage prevents much of this fat embolism, and hence the decrease in cardiac output. The relatively mild hypotension after lavage was secondary to transient vasodilation, which may accentuate the hypotension caused by the decreased cardiac output due to a large embolic fat load. We make recommendations for the prevention and management of hypotension during cemented arthroplasty.

Hypotension during cemented arthroplasty. Relationship to cardiac output and fat embolism

A bilateral cemented arthroplasty (BCA) in anesthetized mongrel dogs creates pulmonary fat and marrow embolism. A transient increase in plasma concentration of 6-keto prostaglandin F1 alpha and thromboxane B2 has been associated with hemodynamic instability after BCA. We tested whether intravenous ibuprofen (20 mg/kg) could inhibit prostaglandin production, pulmonary hypertension, and decreased arterial blood pressure in this model. We found a decrease in cardiac output from 3.0 +/- 0.5 to 2.2 +/- 1.3 L/min (mean +/- 1 SD) after BCA with a flow probe placed at thoracotomy around the ascending thoracic aorta. Systemic arterial blood pressure decreased from 140 +/- 11 to 100 +/- 15 mm Hg (P less than 0.0001), and pulmonary artery pressure increased from 17.7 +/- 3.3 to 37.1 +/- 9.4 mm Hg (P less than 0.0001). Similar hemodynamic changes were noted in 12 dogs without thoracotomy. Pretreatment with ibuprofen did not significantly attenuate the acute hemodynamic changes despite inhibiting prostaglandin generation. We conclude that decreased arterial blood pressure after BCA is associated with a decrease in cardiac output and that inhibition of prostaglandin production with ibuprofen does not prevent either pulmonary hypertension or systemic hypotension.

J B Mullen

Papers

Cardiopulmonary function and pulmonary microemboli during arthroplasty using cemented or non-cemented components. The role of intramedullary pressure.

High-volume, high-pressure pulsatile lavage during cemented arthroplasty.

Hypotension during cemented arthroplasty. Relationship to cardiac output and fat embolism

Ibuprofen pretreatment does not prevent hemodynamic instability after cemented arthroplasty in dogs.