Platelet count abnormalities and peri-operative outcomes in adults undergoing elective, non-cardiac surgery.

BACKGROUND:Anemia and transfusion of blood in the peri-operative period have been shown to be associated with increased morbidity and mortality across a wide variety of non-cardiac surgeries. While tests of coagulation, including the platelet count, have frequently been used to identify patients with an increased risk of peri-operative bleeding, results have been equivocal. The aim of this study was to assess the effect of platelet level on outcomes in patients undergoing elective surgery. MATERIALS AND METHODS:Retrospective cohort analysis of prospectively-collected clinical data from American College of Surgeons National Surgical Quality Improvement Program (NSQIP) between 2006-2016. RESULTS:We identified 3,884,400 adult patients who underwent elective, non-cardiac surgery from 2006-2016 at hospitals participating in NSQIP, a prospectively-collected, national clinical database with established reproducibility and validity. After controlling for all peri- and intraoperative factors by matching on propensity scores, patients with all levels of thrombocytopenia or thrombocytosis had higher odds for perioperative transfusion. All levels of thrombocytopenia were associated with higher mortality, but there was no association with complications or other morbidity after matching. On the other hand, thrombocytosis was not associated with mortality; but odds for postoperative complications and 30-day return to the operating room remained slightly increased after matching. CONCLUSIONS:These findings may guide surgeons in the appropriate use and appreciation of the utility of pre-operative screening of the platelet count prior to an elective, non-cardiac surgery

Use and Utility of Hemostatic Screening in Adults Undergoing Elective, Non-Cardiac Surgery.

One view of value in medicine is outcome relative to cost of care provided. With respect to operative care, increased attention has been placed on evaluation and optimization of patients prior to undergoing an elective surgery. We examined more than 2 million patients having elective, non-cardiac surgery to assess the incidence and utility of pre-operative hemostatic screening, compared with a composite of history variables that may indicate a propensity for bleeding, to assess several important outcomes of surgery.We queried the NSQIP database to identify 2,020,533 patients and compared hemostatic tests (PT, aPTT, platelet count) and history covariables indicative of potential for abnormal hemostasis. We compared outcomes across predictor values; used Person's chi-square tests to compare differences, and logistic regression to model outcomes.Approximately 36% of patients had all three tests pre-operatively while 16% had none of them; 11.2% had a history predictive of potential abnormal bleeding. Outcomes of interest across the cohort included death in 0.7%, unplanned return to the operating room or re-admission within 30 days in 3.8% and 6.2% of patients; 5.3% received a transfusion during or after surgery. Sub-analyses in each of the nine surgical specialties' most common procedures yielded similar results.The limited predictive value of each hemostatic screening test, as well as excess costs associated with them, across a broad spectrum of elective surgeries, suggests that limiting pre-operative testing to a more select group of patients may be reasonable, equally efficacious, efficient, and cost-effective

Predictive value of “patient history indicating potentially abnormal coagulation”, abnormal hemostatic test results, both, and neither in patients screened with all 3 hemostatic tests (n = 728,135).

<p>* History = History indicative of potentially abnormal hemostasis</p><p>Predictive value of “patient history indicating potentially abnormal coagulation”, abnormal hemostatic test results, both, and neither in patients screened with all 3 hemostatic tests (n = 728,135).</p

Abnormal screening test Odds Ratios by patient “history indicative of potentially abnormal hemostasis” in surgery patients screened with all 3 hemostasis tests (n = 728,135).

<p>aPTT = activated partial thromboplastin time; CI = confidence interval; INR = International Normalized Ratio; OR = operating room; RBC = red blood cell</p><p>* History = History indicative of potentially abnormal hemostasis</p><p>† Odd ratios and p values that are significant are bolded.</p><p>Abnormal screening test Odds Ratios by patient “history indicative of potentially abnormal hemostasis” in surgery patients screened with all 3 hemostasis tests (n = 728,135).</p

General demographics, preoperative hemostatic screening tests, patient history variables, and outcomes of interest of all surgery patients (n = 2,020,533).

<p>ASA = American Association of Anesthesiologists; INR = International Normalized Ratio; aPTT = activated partial thromboplastin time; RBC = red blood cell; OR = operating room; SD = standard difference</p><p>^† Number of patients who underwent each of the preoperative hemostatic tests within 90 days prior to surgery.</p><p>^‡ Patient had one or more of the following risk factors for abnormal hemostasis: history of abnormal bleeding, self-reported family history of bleeding disorders, vitamin K deficiency, currently taking medications that pose a risk for bleeding abnormalities and/or failing to discontinue use of such medications with adequate time for normal hemostasis to be restored, chronic steroid use, chemotherapy and/or radiotherapy for cancer within 90 days prior to surgery, disseminated cancer, renal disease, and/or hepatic disease.</p><p>General demographics, preoperative hemostatic screening tests, patient history variables, and outcomes of interest of all surgery patients (n = 2,020,533).</p

Patient selection criteria.

<p>A schematic of the patients included and excluded in this study from the entire population in NSQIP (n = 2,301,079).</p

Outcome Odds Ratios by patient “history indicative of potentially abnormal hemostasis” in all surgery patients (N = 2,020,533).

<p>CI = confidence interval; RBC = red blood cell; OR = operating room</p><p>* History = History indicative of potentially abnormal hemostasis</p><p>† Odd ratios and p values that are significant are bolded.</p><p>Outcome Odds Ratios by patient “history indicative of potentially abnormal hemostasis” in all surgery patients (N = 2,020,533).</p

Outcome Odds ratios by number of abnormal hemostasis test results in 728,135 surgery patients who underwent all 3 hemostasis tests.

<p>CI = confidence interval; OR = operating room; RBC = red blood cell</p><p>* Odd ratios are relative to all three tests within normal range.</p><p>^† Pearson's chi-square test used to compare differences in outcomes across all groups.</p><p>‡ Odd ratios and p values that are significant are bolded.</p><p>Outcome Odds ratios by number of abnormal hemostasis test results in 728,135 surgery patients who underwent all 3 hemostasis tests.</p