Outcomes Following Posterior Lumbar Fusion in Patients with Polycythemia Vera

BACKGROUND

Polycythemia vera (PV) is a chronic myeloproliferative neoplasm that is associated with increased risk for venous and arterial thromboembolism. The aim of this study was to evaluate outcomes following elective posterior lumbar fusion (PLF) and/or posterior interbody fusion (PLIF) among patients with PV.

METHODS

Using PearlDiver retrospective national database, Medicare patients <85 years old who underwent elective primary PLF (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code 81.07) and/or PLIF (ICD-9-CM code 81.08) for degenerative lumbar spine pathologies during 2006-2013 were identified. Patients included in the PLF and/or PLIF cohort were separated into patients with a prior diagnosis of PV (ICD-9-CM code 238.4) and a control cohort of patients without PV. Comparisons of postoperative outcomes were made between the PV patient group and matched control group. Significance was set at 0.05.

RESULTS

Selected study participants included 1491 patients with PV and 29,056 patients in the matched control group. Patients with PV had a significantly increased rate of 90-day acute pulmonary embolism (1.9% vs. 1.2%, odds ratio [OR] 1.65, 95% confidence interval [CI] 1.10-2.38, P = 0.010), 90-day lower extremity deep vein thrombosis (3.4% vs. 1.9%, OR 1.81, 95% CI 1.33-2.40, P < 0.001), and 1-year diagnosis of surgical site infection (5.4% vs. 4.2%, OR 1.30, 95% CI 1.02-1.63, P = 0.027) compared with patients without PV. Nonetheless, PV was not associated with other major medical complications, including stroke, myocardial infarction, and mortality, following PLF and/or PLIF.

CONCLUSIONS

Patients with PV undergoing elective PLF and/or PLIF have a significantly increased risk for pulmonary embolism, lower extremity deep vein thrombosis, and surgical site infection.

Laparoscopic hepatectomy in a patient with uncontrolled polycythaemia vera

This case report describes the peri-operative course of a patient with uncontrolled polycythaemia vera who underwent a laparoscopic hepatectomy for intrahepatic cholangiocarcinoma. Polycythaemia vera is a chronic condition that results in erythrocytosis and puts patients at risk of peri-operative complications including thrombotic events and paradoxical haemorrhage. Little evidence exists on the ideal peri-operative management of uncontrolled polycythaemia vera when the proposed procedure carries a high risk of haemorrhage. Our patient presented with a pre-operative haemoglobin of 197 g.l^-1 (haematocrit 65%) and was not phlebotomised pre-operatively. Intra-operatively he lost 2700 ml of blood, reducing his haematocrit to 48%, and then suffered fatal thrombotic complications postoperatively. The patient did not receive any blood product transfusions during his peri-operative course. We review the available evidence to guide the peri-operative management of patients with polycythaemia vera. The inherent risks of thrombosis and haemorrhage associated with polycythaemia vera need to be weighed against the specific surgical and transfusion-related risks. Phlebotomy to achieve a pre-operative haematocrit under 45% is recommended and intra-operative phlebotomy shows promise for reducing blood loss during hepatectomies. Management of postoperative erythrocytosis may be an important and underappreciated aspect of reducing the peri-operative risk of thrombosis in patients with polycythaemia vera.

Successful perioperative management of a patient with erythropoietin-producing uterine myoma

Background

Erythropoietin-producing uterine myoma can cause various complications such as arterial or venous thrombosis and bleeding. Therefore, caution is required in the anesthetic management of affected patients.

Case presentation

A 57-year-old female was suspected to have an erythropoietin-producing uterine myoma and was scheduled to undergo an abdominal total hysterectomy and bilateral salpingo-oophorectomy. Preoperative levels of hemoglobin and erythropoietin were 21.9 g/dl (normal 11.5–15 g/dl) and 23.2 IU/ml (normal 4.2–23.7 IU/ml), respectively. Preoperative phlebotomy and isovolemic hemodilution were performed to prevent arterial and venous thrombosis, following previous evidence that a hemoglobin level < 16 g/dl reduces the occurrence of polycythemia vera-related complications. Fondaparinux 2.5 mg was subcutaneously injected once daily after the operation, resulting in a good perioperative course without major complications.

Conclusion

Herein, we have described a successful perioperative management of a patient with erythropoietin-producing uterine myoma. Our findings in this case suggest that this combination of antithrombotic therapies can facilitate anesthetic management of patients with this disease.

Perioperative blood product administration and thromboembolic events in patients with treated polycythemia vera: a case-control study

BACKGROUND

Patients with polycythemia vera (PV) have historically been considered to be at high risk for perioperative hemorrhagic and thromboembolic complications. However, no recent studies have compared these outcomes between treated PV patients and patients without PV undergoing similar procedures.

STUDY DESIGN AND METHODS

Patients with PV who underwent surgery with anesthesia from June 1, 2006, to May 31, 2011, were randomly matched (sex, age, type of surgical procedure, surgical year) at a ratio of 1:4 with control patients without PV. Conditional logistic regression analysis adjusting for surgical duration, preoperative hemoglobin, platelet count, and cardiovascular disease was used to assess the association between PV and blood product transfusions, thromboembolism, and other major cardiovascular and pulmonary complications.

RESULTS

Fifty-six PV patients who underwent 79 surgeries were matched with 312 controls. During hospitalization, 35 (44.3%) and 82 (25.9%) PV and control patients, respectively, were transfused with blood products. PV patients were at increased risk for transfusion intraoperatively (odds ratio [OR], 4.35; 95% confidence interval [CI], 1.79-10.57; p = 0.001) and during hospitalization (OR, 4.35; 95% CI, 1.84-10.31; p < 0.001). The likelihood of thromboembolic complications and/or other major complications did not differ between the two study groups (thromboembolic-OR 1.53, 95% CI 0.39-6.02, p = 0.540; other major complications-OR 2.15, 95% CI 0.93-4.96, p = 0.073).

CONCLUSIONS

Medically managed PV patients had an increased likelihood of receiving blood products perioperatively. Given the low number of observed thromboembolic events, we cannot make definitive conclusions regarding the association between PV and thromboembolism.

Raised haematocrit concentration and the risk of death and vascular complications after major surgery

Background

Preoperative anaemia is associated with adverse postoperative outcomes. Data on raised preoperative haematocrit concentration are limited. This study aimed to evaluate the effect of raised haematocrit on 30-day postoperative mortality and vascular events in patients undergoing major surgery.

Methods

This was a cohort study using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database. Thirty-day mortality and vascular events, demographics and perioperative risk factors were obtained for adults undergoing major surgery. The adjusted effect of raised (over 0·50) compared with normal (0·41–0·50, American Medical Association reference range) preoperative haematocrit concentration on postoperative outcomes was assessed. Separate sex-specific analyses were also conducted, using haematocrit concentration thresholds commonly used in the diagnosis and management of apparent or absolute erythrocytosis.

Results

Some 3961 (2·0 per cent) of 197 469 patients had a raised haematocrit concentration before surgery. After adjustment, the 30-day postoperative mortality rate was higher in patients with raised haematocrit than in those without (odds ratio (OR) 2·23, 95 per cent confidence interval 1·77 to 2·80). Thirty-day rates of deep vein thrombosis (OR 1·95, 1·44 to 2·64) and pulmonary embolism (OR 1·79, 1·17 to 2·73), but not myocardial infarction or stroke, were also higher in patients with a raised haematocrit concentration. The effect on mortality was noted beyond the haematocrit thresholds of 0·48 in women and 0·52 in men; the effect estimates were considerably higher for values exceeding 0·54. Values between 0·41 and 0·45 were not associated with increased mortality risk. Similar observations were noted for venous thrombosis, although with apparent sex differences.

Conclusion

A raised haematocrit concentration was associated with an increased risk of 30-day mortality and venous thrombosis following major surgery.

Preoperative Evaluation of the Patient for Vascular Surgery in the "Real World"

Patients presenting for vascular surgery frequently have multiple coexisting diseases. To meet the goal of providing a safe anesthetic with optimum resource use, we must ex amine the impact of each of these conditions on the patient and how the data from a particular evaluation or test will impact our anesthetic plan. Existing guidelines may be valu able if adapted to institution-specific circumstances. Con sultants represent a relatively high-cost resource, which can be optimized when used with clear goals in sight. Finally, we may be able to modify our evaluation based on the antici pated procedure, as these patients are exposed to a range of potential hemodynamic stresses.

Primary polycythaemia vera in the elderly

At presentation the history of an 87-year-old woman included progressive memory loss, repeated transient ischaemic attack, increasing fatigue, dizziness, palpitations and frequent falls. Investigations revealed erythrocytosis, leukocytosis, thrombocytosis, normal arterial oxygen concentration and an increased red cell volume. Polycythaemia vera was diagnosed and was successfully managed by phlebotomy with half a unit twice a week and rechecks of her haematocrit, initially; she reported marked improvement after 2 weeks of treatment. The alternative treatments for polycythaemia vera are discussed; in addition to venesection, conventional treatments include bone-marrow depressive agents such as phosphorus-32 and chemotherapy with agents such as hydroxyurea. More recent developments include isovolumic erythrocytophoresis, alpha-interferon and ticlopidine. All of the treatments are associated with complications, or other disadvantages, thrombotic complications in the case of phlebotomy, malignancies in the case of most myelosuppressive treatments, and problems of compliance in others. The optimal treatment for polycythaemia vera is a judicious combination of the alternatives, depending on the phase of the disease, the age of the patient, and other prognostic factors.

Chronic myeloproliferative disorders: prognostic importance of new working classification

Variants of chronic myeloproliferative disorders (CMPD) were compared according to their clinical features and classified by bone marrow biopsy appearances. Subsequently, this classification was further evaluated using survival data and histological variables from iliac crest biopsy specimens of an additional 1391 patients, making a total of 2241 patients available for analysis of outcome. The patients were grouped again into three main classes: "typical"; "variant"; and "transformed". "Typical" comprised the "classic" groups. "Variant" included the less uniform myeloproliferative syndromes, distinguished also by more variable clinical features, a different prognosis, and a greater tendency to fibrotic and blastic transformation. "Transformed" defined the end stages of both "typical" and "variant" types. Ten subgroups were distinguished by different histology and prognosis. Particular prognostic importance was assigned to atypia and immaturity of haemopoiesis, predominance of individual haemopoietic cell line, number and anomalies of megakaryocytes and progressive fibrosis. It is suggested that the proposed subclassification would be helpful for studies of epidemiology and therapeutic trials by allowing more homogeneous groups to be recognised.

Hematologic problems in the preoperative patient

A number of topics have been reviewed pertaining to hematologic problems in preoperative patients. Most if not all of the problems discussed can be evaluated reasonably well by history, physical examination, and a few simple laboratory tests. Because the morbidity arising from some of these abnormalities can be quite significant, evaluation and treatment should be completed prior to surgery whenever possible. It is also critical to recall that therapy for a number of hematologic problems involves the transfusion of blood or blood products. This therapy should not be taken lightly as both immediate reactions (fever, anaphalaxis, hemolysis) as well as delayed effects (allosensitization and viral infections) occur frequently. The prudent clinician should try to minimize his patients' exposure to these potentially toxic materials by using alternative therapies.