Preoperative screening for coagulopathy in elective neurosurgical patients in Wellington Regional Hospital and survey of practice across Australia and New Zealand.

It is common practice to perform pre-operative coagulation screening in elective neurosurgery patients, including international normalised ratio (INR) and activated partial thromboplastin time (aPTT). We present a retrospective analysis of 1143 elective neurosurgical patients at Wellington Regional Hospital (WRH) in New Zealand between 2013 and 2017 on whom coagulation screening including INR and aPTT was performed prior to surgery. 21 patients (1.8%) had clinically significant derangements on coagulation profile defined as raised INR or prolonged aPTT. 15 (1.3%) of these patients would be expected to have derangement based on previous history and 6 (0.5%) had unexpected derangements in coagulation profile. Of the 6 patients with unexpected derangements in coagulation profile, all had raised aPTT, none had preoperative correction of coagulopathy and none had bleeding complications or mortality. The cost of coagulation screening across the duration of the study was $68,009 New Zealand Dollars (NZD). A survey of major elective neurosurgery units in Australia and New Zealand found that 85% perform routine laboratory coagulation screening. In the 15% who do not perform laboratory coagulation screening, none use a standardised questionnaire to screen for coagulopathy. We developed a structured questionnaire to assist in detection of coagulopathy in elective neurosurgery patients. Our findings suggest that there is limited value in performing indiscriminate laboratory coagulation screening in patients with no risk factors on history. Despite this, routine laboratory coagulation screening is common practice in Australia and New Zealand. We propose a structured questionnaire to guide laboratory testing and discussions with haematology colleagues.

The risk of early and late CMV DNAemia associated with Campath use in stem cell transplant recipients.

The risks associated with in vivo and ex vivo use of Campath-1H and -1G in a cohort of 206 stem cell transplant recipients for human CMV (HCMV) DNAemia have been quantified. DNAemia showed a biphasic incidence pattern with an inflexion at day 60. The first phase had a linear risk rate for HCMV DNAemia of 0.3% per day, whereas the second phase had a substantially lower risk rate of 0.058% per day. In multivariable analyses, risk factors for early DNAemia were HCMV serostatus, radiotherapy-based conditioning and CD34 stem cell dose, with the use of in vivo Campath-1H having the most significant risk (hazards ratio=3.68; 95% CI=2.02-6.72; P<0.001). Ex vivo use of Campath was not associated with an increased risk for HCMV DNAemia. Patients receiving either in vivo Campath-1H or -1G experienced HCMV DNAemia earlier (27 and 33 days, respectively) compared with patients receiving no Campath (time to DNAemia, 51 days; P=0.0006). Multivariable analysis of risk factors for HCMV DNAemia occurring beyond 100 days after transplant were older age, acute GVHD>grade II and a lower CD34 stem cell dose, whereas Campath-1H use was not associated with late HCMV DNAemia.

Prior immunosuppressive therapy with antithymocyte globulin increases the risk of EBV-related lymphoproliferative disorder following allo-SCT for acquired aplastic anaemia.

We reviewed the incidence and risk factors for EBV-related post-transplant lymphoproliferative disorder (EBV-PTLD) in 89 patients with acquired aplastic anaemia (AAA) receiving allogeneic transplants between 1989 and 2006. The overall incidence of EBV-PTLD was 6.3% (5/89) with no cases in those receiving an allograft for constitutional BM failure syndromes (n=30) during the same period. There was no impact of age, gender, donor status, CMV seropositivity, GVHD and graft cell dose on the occurrence of PTLD. Although both reduced intensity conditioning (RIC) and the prior use of antithymocyte globulin (ATG), as immunosuppressive therapy (IST), were identified as the risk factors for PTLD, only prior use of ATG strongly influenced the development of PTLD with an incidence of 13.38+/-5.6% (5/43), compared with none in those not exposed to ATG before transplantation (P=0.01) with a relative risk of 10.39 for each course of prior ATG. This is the first study in patients with AAA documenting that those receiving multiple prior courses of ATG are at the highest risk of developing EBV-PTLD.

Effect of propofol on heart rate, arterial pressure and digital plethysmograph variability.

We have investigated the effects of propofol on beat-to-beat fluctuations in heart rate, arterial pressure (continuous arterial tonometry) and infrared finger plethysmography in 10 healthy male patients undergoing elective surgery. Administration of Diprivan (propofol 10 mg ml-1) 0.2 ml kg-1, followed by an infusion of 1 ml kg-1 h-1, was associated with transient tachycardia and a reduction in arterial pressure that preceded an increase in plethysmograph amplitude. The temporal sequence of these cardiovascular changes suggests that the initial tachycardia was not a reflex response to hypotension and that cutaneous changes in adrenergic tone were not responsible for the decrease in arterial pressure. The observation that the hypotensive action of propofol preceded the increase in plethysmographic amplitude suggests that multiple mechanisms were implicated in the hypotensive action of propofol and the relative importance of these mechanisms may vary according to the time of measurement. Compared with preanaesthetic control values, spectral analysis of heart rate variability, arterial pressure and plethysmograph variability showed reduction in variability and total spectral power. Spectral power in low (< 0.08 Hz) and mid (0.08-0.15 Hz) frequency bands decreased for each variable, while high (> 0.15 Hz) frequency "ventilatory" power decreased for heart rate and possibly diastolic pressure and increased for systolic pressure and plethysmograph variability.(ABSTRACT TRUNCATED AT 250 WORDS)