Dinesh Parmar

Introduction: Diabetic ketoacidosis (DKA) is a common complication of diabetes mellitus characterized by metabolic acidosis, ketogenesis, hypovolemia, hyperglycemia, and electrolyte depletion. During treatment of DKA with intravenous fluids and insulin, some electrolyte disturbances can worsen. Hypophosphatemia is one such electrolyte disturbance that has not been well characterized in patients with severe DKA requiring Intensive Care Unit (ICU) admissions. This study sought to evaluate the incidence, severity, associations, and outcomes of hypophosphatemia in DKA. Methods: This retrospective multicenter study was conducted across DKA admissions to Queensland ICUs from 2016 to 2021. Adult patients (>18 years) requiring ICU admission for management of DKA were included in this study. Patients with DKA were stratified by lowest recorded phosphate level as: normal ≥ 0.80 mmol/L, mild 0.50–0.79 mmol/L, moderate 0.30–0.49 mmol/L and severe < 0.3 mmol/L. Patient demographics, comorbidities, ICU-related supports, and medications (including fluid, insulin administration, phosphate, and other electrolyte replacement) were collected. Univariate analysis was performed between hypophosphatemia severity and normophosphatemia subgroups to determine risk factors, outcomes, replacement, and progression of hypophosphatemia in the ICU. Phosphate replacement and administered insulin was compared to nadir serum phosphate level. Multivariate analysis and linear regression were performed to identify risk factors for the development of hypophosphatemia. Results: A total of 842 admissions of 669 unique patients due to DKA were included; 436 of 842 (51.8%) admissions maintained normophosphatemia in the ICU, while 220 (26.1%, n = 220/842) had mild hypophosphatemia, 124 (14.7%, n = 124/842) had moderate hypophosphatemia and 62 (7.4%, n = 62/842) had severe hypophosphatemia. Patients with higher BMI, higher APACHE II/III score, cerebrovascular disease and all blood gas parameters (excluding PaO₂) were found to have more severe hypophosphatemia. Lower serum phosphate was associated with greater replacement and greater insulin administration per kilogram body weight. ICU length of stay, hospital length of stay and mortality were not affected by degree of hypophosphatemia (p > 0.05). Linear regression revealed that standard base excess was strongly associated with the development of hypophosphatemia (β = 0.02, 95% CI 0.01–0.02, p < 0.001). Conclusions: Increasing severity of hypophosphatemia was associated with increasing severity of DKA. Increased ICU length of stay was related to increased severity of hypophosphatemia.

The temporal trends in haematological parameters and their associations with blood product transfusion requirements in patients supported with extracorporeal membrane oxygenation (ECMO) are poorly understood. We performed a retrospective data analysis to better understand the behaviour of haematological and coagulation parameters and their associations with transfusion requirements during ECMO. Methods: Patient demographics, haematological and coagulation parameters, plasma haemoglobin and fibrinogen concentrations, platelet count, the international normalised ratio (INR), the activated partial thromboplastin time (APTT), and blood product transfusion data from 138 patients who received ECMO in a single high-volume centre were analysed. Results: Ninety-two patients received venoarterial (VA) ECMO and 46 patients received venovenous (VV) ECMO. The median (IQR) duration of VA, and VV ECMO was 8 (5–13) days and 13 (8–23) days, respectively. There were significant reductions in haemoglobin, the platelet count, and the fibrinogen concentration upon initiation of ECMO. On average, over time, patients on VV ECMO had platelet counts 44 × 10⁹/L higher than those on VA ECMO (p ≤ 0.001). Fibrinogen and APTT did not vary significantly based on the mode of ECMO (p = 0.55 and p = 0.072, respectively). A platelet count < 50 × 10⁹/L or a fibrinogen level < 1.8 g/L was associated with 50% chance of PRBC transfusion, regardless of the ECMO type, and packed red blood cell (PRBC) transfusion was more common with VA ECMO. APTT was predictive of the transfusion requirement, and the decrement in APTT was discriminatory between VVECMO survivors and nonsurvivors. Conclusion: ECMO support is associated with reductions in haemoglobin, platelet count, and fibrinogen. Patients supported with VA ECMO are more likely to receive a PRBC transfusion compared to those on VV ECMO. Thrombocytopaenia, hypofibrinogenaemia, and anticoagulation effect the likelihood of requiring PRBC transfusion. Further research is needed to define optimal blood management during ECMO, including appropriate transfusion triggers and the anticoagulation intensity.