Comparison of different platelet transfusion thresholds prior to insertion of central lines in patients with thrombocytopenia

Critical Care: What You May Have Missed in 2023

Critical care medicine is a specialty that brings together a truly wide spectrum of patient populations, disease states, and treatment methods. This article highlights 10 important pieces of research from 2023 (and 1 from 2022) in critical care. The literature was screened for new evidence relevant to internal medicine physicians and hospitalists whose focus of practice is not critical care but who may be taking care of seriously ill patients. The articles highlight the diverse spectrum of pathology and interplay of various specialties that go into critical care. Topics include transfusion medicine, fluid resuscitation, safe intubation practices and respiratory failure, and the management of acute ischemic stroke. Several trials are groundbreaking, forcing clinicians to reconsider preexisting dogma and likely adopt new treatment strategies.

Minimum platelet count threshold before invasive procedures in cirrhosis: Evolution of the guidelines

Cirrhotic patients with severe thrombocytopenia are at increased risk of bleeding during invasive procedures. The need for preprocedural prophylaxis aimed at reducing the risk of bleeding in cirrhotic patients with thrombocytopenia who undergo scheduled procedures is assessed via the platelet count; however, establishing a minimum threshold considered safe is challenging. A platelet count ≥ 50000/μL is a frequent target, but levels vary by provider, procedure, and specific patient. Over the years, this value has changed several times according to the different guidelines proposed in the literature. According to the latest guidelines, many procedures can be performed at any level of platelet count, which should not necessarily be checked before the procedure. In this review, we aim to investigate and describe how the guidelines have evolved in recent years in the evaluation of the minimum platelet count threshold required to perform different invasive procedures, according to their bleeding risk.

Lowering platelet count threshold to 10,000/µL for peripherally inserted central catheter placement safely conserves blood products

Despite the low risk of peripherally inserted central catheter (PICC) insertion-related bleeding, the practice of administering prophylactic platelets varies greatly. Limiting unnecessary blood product transfusions reduces transfusion-related adverse events, financial cost, and delays in care. We assessed the impact of lowering prophylactic platelet administration threshold on blood product utilization patterns and bleeding events. This quasi-experimental study was conducted in an urban academic tertiary medical center. The study population included patients with platelet counts ≥ 10,000/µL and < 50,000/µL undergoing PICC placement in 2018 and 2019 when the minimum platelet thresholds were 50,000/µL and 10,000/µL, respectively. The primary outcome was blood product utilization and the secondary outcome was PICC insertion-related bleeding complications. Thirty-five patients using the 10,000/µL (10 K) platelet threshold and 46 patients using the 50,000/µL (50 K) platelet threshold were enrolled. The 50 K group received more platelets before PICC insertion (0.870 ± 0.885 and 0.143 ± 0.430 pools of platelets-per-person, p < 0.001). No patients experienced clinically significant bleeding. Immediately following PICC insertion, minor bleeding occurred in five patients (two [4.3%] and three [8.6%] in the 50 K and 10 K groups, respectively). Bleeding rates between the two cohorts did not differ (p = 0.647). Lowering the minimum platelet threshold from 50,000/µL to 10,000/µL resulted in less prophylactic platelet and total blood product administration with no appreciable difference in PICC insertion-related bleeding.

Central venous catheterization in cancer patients with severe thrombocytopenia: Ultrasound-guide improves safety avoiding prophylactic platelet transfusion

Prior research has revealed that ultrasound (US) guided central venous catheterization (CVC) is associated with a reduction in the complication rate such as pneumothorax and an improved first-pass success placing CVC in the internal jugular vein. The present study investigated if US-guided CVC, in a subset of cancer patients with severe thrombocytopenia, reduced bleeding risk and avoided prophylactic platelet transfusion. The efficacy and safety of US-guided CVC placement in cancer patients with severe thrombocytopenia was retrospectively analyzed over a period of 9 years (Dec 2000-Jan 2009), 1,660 and 207 patients with cancer underwent US-guided CVC placement into internal jugular vein respectively at the Department of Onco-Haematology, Hospital of Piacenza. The first group of patients included patients in active antitumor treatment, while the second group included patients in the palliative phase. A total of 110 (5.89%) of these 1,867 patients exhibited severe thrombocytopenia defined as platelet count ≤20x109/l, and formed the basis of this study. All procedures were evaluated for bleeding complications as defined by the National Institute of Health Common Terminology Criteria for Adverse Events (CTCAE 3.0). In the subgroup of the 110 patients with severe thrombocytopenia a single needle puncture of the vein was employed in 121 of the 122 procedures (99.18%) and no attempt failures were registered. No pneumothorax, no major bleeding and no nerve and arterial puncture were reported, only one self-limiting hematoma (0.90%) at the site of CVC insertion was reported (CTCAE 3.0 grade 1). No platelet transfusions were performed in the 110 patients, pre and post CVC placement. We believe that US-guided CVC insertion procedures into the internal jugular vein makes the difference in safety, also in thrombocytopenic patients avoiding prophylactic or post procedure platelet transfusion.

Clinical Implications of Thrombocytopenia for the Cirrhotic Patient

Thrombocytopenia is a frequent complication in patients with cirrhosis. As many as 84% of patients with cirrhosis have thrombocytopenia, and it is an independent variable indicative of advanced disease and poor prognosis. Although there is great concern that it may aggravate bleeding during surgical procedures, there is limited evidence to inform decisions regarding the treatment of cirrhotic patients with thrombocytopenia undergoing invasive procedures. Finally, there is evidence that platelets play a significant role in liver regeneration. In this report, the clinical implications of thrombocytopenia in cirrhotic patients are reviewed. The utility of platelet counts in the prognosis of cirrhosis and relationship to complications of advanced liver disease, including portal hypertension, esophageal varices, and hepatocellular carcinoma. The impact of low platelet counts on bleeding complications during invasive procedures is outlined. Finally, the role of platelets and potential adverse impact in liver regeneration is reviewed.

Prophylactic platelet transfusions prior to surgery for people with a low platelet count

BACKGROUND

People with thrombocytopenia often require a surgical procedure. A low platelet count is a relative contraindication to surgery due to the risk of bleeding. Platelet transfusions are used in clinical practice to prevent and treat bleeding in people with thrombocytopenia. Current practice in many countries is to correct thrombocytopenia with platelet transfusions prior to surgery. Alternatives to platelet transfusion are also used prior surgery.

OBJECTIVES

To determine the clinical effectiveness and safety of prophylactic platelet transfusions prior to surgery for people with a low platelet count.

SEARCH METHODS

We searched the following major data bases: Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), PubMed (e-publications only), Ovid MEDLINE, Ovid Embase, the Transfusion Evidence Library and ongoing trial databases to 11 December 2017.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs), as well as non-RCTs and controlled before-and-after studies (CBAs), that met Cochrane EPOC (Effective Practice and Organisation of Care) criteria, that involved the transfusion of platelets prior to surgery (any dose, at any time, single or multiple) in people with low platelet counts. We excluded studies on people with a low platelet count who were actively bleeding.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane for data collection. We were only able to combine data for two outcomes and we presented the rest of the findings in a narrative form.

MAIN RESULTS

We identified five RCTs, all conducted in adults; there were no eligible non-randomised studies. Three completed trials enrolled 180 adults and two ongoing trials aim to include 627 participants. The completed trials were conducted between 2005 and 2009. The two ongoing trials are scheduled to complete recruitment by October 2019. One trial compared prophylactic platelet transfusions to no transfusion in people with thrombocytopenia in an intensive care unit (ICU). Two small trials, 108 participants, compared prophylactic platelet transfusions to other alternative treatments in people with liver disease. One trial compared desmopressin to fresh frozen plasma or one unit of platelet transfusion or both prior to surgery. The second trial compared platelet transfusion prior to surgery with two types of thrombopoietin mimetics: romiplostim and eltrombopag. None of the included trials were free from methodological bias. No included trials compared different platelet count thresholds for administering a prophylactic platelet transfusion prior to surgery. None of the included trials reported on all the review outcomes and the overall quality per reported outcome was very low.None of the three completed trials reported: all-cause mortality at 90 days post surgery; mortality secondary to bleeding, thromboembolism or infection; number of red cell or platelet transfusions per participant; length of hospital stay; or quality of life.None of the trials included children or people who needed major surgery or emergency surgical procedures.Platelet transfusion versus no platelet transfusion (1 trial, 72 participants)We were very uncertain whether giving a platelet transfusion prior to surgery had any effect on all-cause mortality within 30 days (1 trial, 72 participants; risk ratio (RR) 0.78, 95% confidence interval (CI) 0.41 to 1.45; very-low quality evidence). We were very uncertain whether giving a platelet transfusion prior to surgery had any effect on the risk of major (1 trial, 64 participants; RR 1.60, 95% CI 0.29 to 8.92; very low-quality evidence), or minor bleeding (1 trial, 64 participants; RR 1.29, 95% CI 0.90 to 1.85; very-low quality evidence). No serious adverse events occurred in either study arm (1 trial, 72 participants, very low-quality evidence).Platelet transfusion versus alternative to platelet transfusion (2 trials, 108 participants)We were very uncertain whether giving a platelet transfusion prior to surgery compared to an alternative has any effect on the risk of major (2 trials, 108 participants; no events; very low-quality evidence), or minor bleeding (desmopressin: 1 trial, 36 participants; RR 0.89, 95% CI 0.06 to 13.23; very-low quality evidence: thrombopoietin mimetics: 1 trial, 65 participants; no events; very-low quality evidence). We were very uncertain whether there was a difference in transfusion-related adverse effects between the platelet transfused group and the alternative treatment group (desmopressin: 1 trial, 36 participants; RR 2.70, 95% CI 0.12 to 62.17; very-low quality evidence).

AUTHORS' CONCLUSIONS

Findings of this review were based on three small trials involving minor surgery in adults with thrombocytopenia. We found insufficient evidence to recommend the administration of preprocedure prophylactic platelet transfusions in this situation with a lack of evidence that transfusion resulted in a reduction in postoperative bleeding or all-cause mortality. The small number of trials meeting the inclusion criteria and the limitation in reported outcomes across the trials precluded meta-analysis for most outcomes. Further adequately powered trials, in people of all ages, of prophylactic platelet transfusions compared with no transfusion, other alternative treatments, and considering different platelet thresholds prior to planned and emergency surgical procedures are required. Future trials should include major surgery and report on bleeding, adverse effects, mortality (as a long-term outcome) after surgery, duration of hospital stay and quality of life measures.