Postsurgery outcomes in patients with polycythemia vera and essential thrombocythemia: a retrospective survey

Incidental thrombocytosis: Should it concern the anesthesiologist?

Preoperative thrombocytosis, often detected incidentally in surgical patients and inadvertently overlooked, has important implications for the anesthesiologists. The primary form is a chronic clonal myeloproliferative disorder usually affecting adults while the secondary type is a benign reactive disease commonly found in children. Serious perioperative hemostatic complications are reported in primary thrombocytosis and hence, a detailed preoperative evaluation and initiation of therapy to lower the platelet count (PC) is required before undertaking surgery. Patients with reactive thrombocytosis however, usually have complication-free surgeries, and if there is no prior evidence of hemostatic complications and the reactive cause can be identified, no specific perioperative intervention may be required. A thorough preanesthetic checkup and implementation of basic thrombo-prophylaxis measures in all patients with a raised PC is advocated. We present here our experience with three infants diagnosed with high preoperative PC, presumably due to reactive causes, who underwent uneventful neurosurgeries at our institution.

Surgical treatment of a ventricular aneurysm in a patient with essential thrombocythemia complicated by acute myocardial infarction: A case report

Essential thrombocythemia (ET) is a chronic clonal myeloproliferative disorder, which is often complicated by arterial or venous thrombosis and idiopathic bleeding diathesis. The present study reports a female patient with ET complicated by acute myocardial infarction, leading to ventricular aneurysm following interventional therapy for 3 years and a subsequent in-stent restenosis. Following careful examination, a ventricular aneurysm resection and coronary artery bypass graft were carried out. During this case, the monitoring and controlling of the platelet count, pre- and post-operatively, was extremely important for successful surgery.

Severe delayed postpolypectomy bleeding in elder patient with post-polycythemia myelofibrosis

BACKGROUND

The interest of the case lies in an unexpected delayed bleeding following an endoscopic procedure in a patient with post-polycythemia myelofibrosis. The case gives the opportunity to discuss the medical management and monitoring of patients with myeloproliferative disorders undergoing minimally invasive surgery interventions.

CASE PRESENTATION

A 75 years old woman affected by post-polycythemia myelofibrosis underwent endoscopy polypectomy followed by a delayed major local bleeding. At the time of the endoscopy followed by bleeding, the platelet count was 837 × 109/L, haemoglobin 113 g/L, PCV 35,2% and WBC 20.22 × 106/L. No antithrombotic prophylaxis with low molecular weight heparin was used. Antiplatelet drug was withdraw seven days before endoscopy and restarted one week after the procedure. Polyp size was 11 x 19 mm and it was located on right side of the colon.

CONCLUSION

There are some patients in whom current guidelines do not apply and our case stress the importance of myeloproliferative neoplasms as a risk factor for complications of endoscopic polypectomy. The delayed haemorrhage we observed suggest to strictly control the patient for a period longer than only one week also in case of antithrombotic treatment with antiplatelet drugs.

Spinal surgery in a patient with essential thrombocythemia resulting in leg paraplegia: a case report

BACKGROUND CONTEXT

Essential thrombocythemia (ET) is a chronic myeloproliferative disorder characterized by a relatively benign clinical course that may be complicated by conflicting thrombosis and bleeding. Postoperative spinal epidural hematoma is an uncommon, but well-known, complication after spinal surgery.

PURPOSE

To describe a patient with ET who underwent surgery for lumbar spinal canal stenosis resulting in leg paraplegia and discuss the perioperative management for ET.

STUDY DESIGN

Case report.

RESULTS

The patient with ET underwent laminoplasty and posterolateral fusion for degenerative spondylolisthesis and spinal stenosis at L4-L5. A hematoma was observed in the epidural cavity after surgery, and emergency surgical evacuation was performed. After revision surgery, bleeding from the wound continued for 2 months, despite transfusions of platelets and coagulation factors, and right unilateral leg paralysis developed.

CONCLUSIONS

This case presentation increases the awareness of this disorder to the spinal community and the need to establish guidelines for the perioperative management of patients who require surgery in similar settings.

Thrombotic complications of myeloproliferative neoplasms: risk assessment and risk-guided management

Philadelphia-negative myeloproliferative neoplasms are considered to be acquired thrombophilic states. Thromboses, both arterial and venous (not rarely in unusual sites), are often the initial events leading to the diagnosis. After diagnosis, the yearly incidence of thrombotic events is highly variable, and ranges from approximately 1% to 10%. The identification of patients at risk who may benefit from antithrombotic therapy remains a challenge, and it is currently based on age and history of thrombotic events. However, the predictive value of these clinical characteristics is rather limited. Few prospective studies and even fewer interventional randomized studies are available, and there are no studies designed to formally validate the use of risk stratification. The implementation of laboratory parameters such as leukocytosis and/or the JAK2 V617F mutation into a scoring system may be of interest. The mechanisms at work leading to thrombosis remain largely speculative, but are likely to be complex and multifactorial, with a prominent role of cell-cell interactions, mostly owing to qualitative changes. The long-term treatment options to prevent thrombosis are, schematically, aspirin alone as primary prevention for the low-risk patients, and cytoreduction combined with aspirin for the other patients. In very low-risk young essential thrombocythemia patients, abstention can even be considered. The optimal duration of anticoagulation after a thrombotic event is not established. All antithrombotic therapies should be balanced with the hemorrhagic risk, which can also be increased in these patients.

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.

How I treat polycythemia vera

Polycythemia vera (PV) is a clonal disorder characterized by unwarranted production of red blood cells. In the majority of cases, PV is driven by oncogenic mutations that constitutively activate the JAK-STAT signal transduction pathway, such as JAK2 V617F, or exon 12 mutations or LNK mutations. Diagnosis of PV is based on the WHO criteria. Diagnosis of post-PV myelofibrosis is established according to the International Working Group for Myeloproliferative Neoplasms Research and Treatment criteria. Different clinical presentations of PV are discussed. Prognostication of PV is tailored to the most frequent complication during follow-up, namely, thrombosis. Age older than 60 years and prior history of thrombosis are the 2 main risk factors for disease stratification. Correlations are emerging between leukocytosis, JAK2(V617F) mutation, BM fibrosis, and different outcomes of PV, which need to be confirmed in prospective studies. In my practice, hydroxyurea is still the "gold standard" when cytoreduction is needed, even though pegylated IFN-alfa-2a and ruxolitinib might be useful in particular settings. Results of phase 1 or 2 studies concerning these latter agents should however be confirmed by the ongoing randomized phase 3 clinical trials. In this paper, I discuss the main problems encountered in daily clinical practice with PV patients regarding diagnosis, prognostication, and therapy.

Hemimandibulectomy and vascularized fibula flap in bisphosphonate-induced mandibular osteonecrosis with polycythaemia rubra vera

This report presents the successful management of an advanced and refractory bisphosphonate-related osteonecrosis of the jaws (BRONJ) by hemimandibulectomy and an osteocutaneous fibula flap reconstruction in a patient with polycythaemia rubra vera, a rare haematological condition in which there is increased risk of thrombosis and haemorrhage. Union of the vascularized bone with the mandible depends on obtaining a BRONJ-free margin and rigid fixation of the bony ends. Magnetic resonance imaging can provide accurate delineation of necrotic bone and area of osteomyelitis. Placement of a 1cm margin beyond this can envisage a BRONJ-free margin. Aggressive medical management of polycythaemia rubra vera by venesection, asprin and cytoreduction therapy along with anticoagulant prophylaxis against thromboembolic events in the first 2 weeks following major surgery can provide the basis of a good surgical and flap outcome. Nevertheless, the possibility of unpredictable haemorrhage must be considered throughout.

Classification of myeloproliferative neoplasms and prognostic factors

Myeloproliferative neoplasms (MPNs) are currently diagnosed according to the World Health Organization (WHO) criteria. Molecular profiling should include the analysis of JAK2 V617F (first, exon 12 only in V617F-negative polycythemia vera [PV]) and MPL mutations (in V617F-negative essential thrombocythemia [ET] and myelofibrosis [MF]). For patients with PV and ET, the risk stratification of low- and high-risk disease requires only two parameters: older than age 60 and prior history of thrombosis. Additionally, it might be important to monitor leukocyte count and know the mutational profile. Survival of patients with MF is defined by the International Prognostic Scoring System (IPSS) model at diagnosis and the Dynamic IPSS (DIPSS) anytime during the course of the disease. The IPSS and the DIPSS are based on patient age older than age 65, presence of constitutional symptoms, hemoglobin level less than 10 g/dL, leukocyte count greater than 25 × 10(9)/L, and circulating blast cells 1% or greater. The DIPSS-plus adds critical prognostic information and suggests also considering cytogenetic categories, platelet count, and red blood cell transfusion need.

Special issues in myeloproliferative neoplasms

Special issues in myeloproliferative neoplasms (MPN) comprise clinical conditions with high relevance for the duration and quality of the patient's life, but with limited evidence to support sound diagnostic and therapeutic recommendations and a low probability of being solved by the current standard of clinical research. These issues include MPN in pregnancy and in children, abdominal vein thrombosis, bleeding complications, surgery, pruritus, and leukemic transformation. Practical suggestions to guide clinical decisions in these settings remain largely empirical, but recently developed guidelines based on experts' consensus may help to tackle these problems. This article reviews the state of the art regarding these issues, with special emphasis on experts' consensus recommendations.

Venous thromboembolism in patients with essential thrombocythemia and polycythemia vera

Polycythemia vera (PV) and essential thrombocythemia (ET) are myeloproliferative neoplasms (MPNs), which generally follow a benign and indolent clinical course. However, venous thromboses are common and constitute the main cause of morbidity and mortality. The discovery of the JAK2V617F mutation and other biomarkers has advanced our understanding of these diseases. There is a strong association between the presence of the JAK2V617F mutation and the development of thrombosis in ET. If venous thrombosis presents with unusual manifestations, the diagnosis of a MPN, such as PV or ET, should be part of the differentials. Treatment of venous thrombosis in MPN follows the same principle as in other patients with venous thrombosis, but careful attention to primary and secondary prophylaxis in addition to heparin-induced thrombocytopenia should be given. Cytoreductive therapy is indicated in high-risk subgroups of PV and ET patients, and alternative therapeutic agents have different effects on risk of venous thrombosis. New therapeutic approaches are emerging, and JAK2 inhibitors, histone deacetylase inhibitors and next-generation anticoagulants are in various stages of clinical development for the treatment of MPN, but their exact role in thrombosis prevention and treatment remains unclear.

Thrombosis in myelofibrosis: prior thrombosis is the only predictive factor and most venous events are provoked

In a retrospective analysis of 205 patients (median age 62 years) with primary myelofibrosis and known JAK2V617F mutational status, 13.2% experienced a vaso-occlusive event at or prior to their diagnosis. After a median follow up of 31 months, post-diagnosis thrombosis occurred in 22 patients (10.7%), including 9 (4.4%) and 16 (7.8%) patients with a total of 9 arterial and 24 venous events, respectively. The majority (71%) of the venous events were temporally associated with other exogenous risk factors for thrombosis such as surgery, line placement or hormonal therapy. On multivariable analysis that included age, JAK2V617F mutation status and leukocyte count as covariates, history of thrombosis was the only predictive variable in general (P=0.04) or when arterial (P=0.007) and venous (P=0.02) thromboses were analyzed separately. The current study demonstrates a higher prevalence of venous, as opposed to arterial, events in PMF, post-diagnosis, and clarifies their nature as being mostly provoked.

How I treat essential thrombocythemia

In the past 5 years we have witnessed significant advances in both the diagnostic process and optimal therapy for patients with essential thrombocythemia (ET). Insights into the underlying molecular mechanisms have been accompanied by the development of new diagnostic tests and by an improved understanding of the relationship between ET and other related myeloproliferative neoplasms, such as polycythemia vera and primary myelofibrosis. In the first part of this review, we describe how recent molecular and histologic studies can be integrated into a streamlined diagnostic process that is applicable to everyday clinical practice. We also address areas of current diagnostic controversy, including heterogeneity within ET and the phenotypic overlap between ET, polycythemia vera, and primary myelofibrosis. In the second part, we provide an overview of our current approach to the treatment of ET, including risk stratification, choice of cytoreductive agent, and a consideration of special situations such as the pregnant or perioperative patient. Areas of controversy discussed include the identification of those at high risk of complications and therapeutic decisions in the younger patient.

Evidence-based patient safety advisory: blood dyscrasias

Rarely, patients with blood disorders may seek to undergo plastic surgery. Although plastic surgeons are not expected to diagnose or manage blood disorders, they should be able to recognize which patients are suitable for surgery and which should be referred to a hematologist before a procedure. This practice advisory provides an overview of the perioperative steps that should be completed to ensure appropriate care for patients with blood disorders.

Cardiac surgery in a patient with essential thrombocythemia: a case report

Patients with essential thrombocythemia (ET) are at increased risk of developing arterial thrombosis. We report a case of a 36-year-man with unstable angina in the presence of occlusion of two coronary arteries with insufficient collateral perfusion. We also found essential thrombocythemia in this patient. The patient underwent coronary artery bypass grafting (CABG). Ten days before surgery, the aspirin was replaced by a prophylactic dose of low-molecular-weight heparin. Postoperative follow-up was complicated by pulmonary embolisms and a cardiac tamponade. We conclude that ET is a risk factor for coronary heart disease that should be treated with aspirin. If a patient needs CABG, aspirin should be continued because of the high risk of thromboembolic events in the high-risk ET patients. (Neth Heart J 2010;18:378-80.).