Is an Acute Perioperative Increase in Creatinine Production Rate a Potential Mechanism for an Early Creatinine-Based Signal of Renal Injury After Cardiac Surgery?

OBJECTIVES: Previous studies report a creatinine-based signal of injury within hours after cardiac surgery, which is sooner than expected based on creatinine kinetic modelling. A plausible mechanism for such an early signal has not been established, but might be explained by an acute perioperative increase in creatinine production rate (Crprod-rate). The authors sought to test the hypothesis that perioperative Crprod-rate increases from baseline in patients undergoing cardiac surgery. DESIGN: Prospective cohort study. SETTING: Academic medical center. PARTICIPANTS: Fifty adult male patients undergoing cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Based on the principle of conservation of mass, precisely timed serial measurements of patient weight, plasma and urine creatinine concentration, and urine volume were used to calculate Crprod-rate over 3 consecutive periods: a baseline period immediately before surgery (period 0), the 24-hour period starting from induction of anesthesia (period 1), and again from 24 to 48 hours after induction of anesthesia (period 2). The primary outcome was change in Crprod-rate from period 0 to period 1 (∆Crprod-rate0-1). Median Crprod-rate0 was 5.4 (interquartile range [IQR], 4.7-5.7) µmol/kg/h at baseline and increased to 6.1 (IQR, 5.6-6.5) µmol/kg/h during period 1, a median increase of 14% (95% CI, 8%-27%; p = 0.002). ∆Crprod-rate0-1 ranged from -58% to +129%, with an increase above baseline in 25 patients (76%) and an increase by ≥30% above baseline in 10 patients (30%). CONCLUSIONS: Perioperative Crprod-rate increased from baseline in patients undergoing cardiac surgery. This may represent a mechanism for an earlier creatinine-based signal of renal injury than previously thought possible.

Body weight change is unpredictable after total thyroidectomy.

BACKGROUND: There is a common perception that total thyroidectomy causes weight gain beyond expected age-related changes, even when thyroid replacement therapy induces a euthyroid state. The aim of this study was to determine whether patients who underwent total thyroidectomy for a wide spectrum of conditions experienced weight gain following surgery. METHODS: We retrospectively studied 107 consecutive total thyroidectomy patients treated between January 2013 and June 2014. Medical records were reviewed to determine underlying pathology, thyroid status, use of antithyroid drugs and preoperative weight. Follow-up data were obtained from 79 patients at least 10 months post-operatively to determine current weight, the type of clinician managing thyroid replacement therapy and patient satisfaction with post-thyroidectomy management. RESULTS: The cohort was 73% female, with a mean age of 55.8 ± 15.7 years and a mean preoperative weight of 78.8 ± 17.5 kg. Commonest pathologies were multinodular goitre, Graves' disease, thyroid cancer and Hashimoto's thyroiditis. Preoperatively, 63.2% of patients were hyperthyroid. Mean weight change at follow-up was a non-significant increase of 0.06 ± 6.9 kg (P = 0.094). Weight change was not significant regardless of preoperative thyroid function status. This study did not demonstrate any significant differences in clinical characteristics (including post-operative thyroid-stimulating hormone) between the group with >2% weight gain and those who did not. CONCLUSIONS: This study did not reveal significant weight gain following thyroidectomy for a wide spectrum of pathologies. Specifically, preoperative hyperthyroidism, female gender and use of antithyroid medications do not predict weight gain after thyroid surgery.

Comfort First: an evaluation of a procedural pain management programme for children with cancer.

BACKGROUND: The Comfort First Program (CFP) provides children and their caregivers with early procedural pain management intervention to reduce procedural pain and distress. This study evaluated whether the CFP was meeting its goals and effectively implementing the Royal Australasian College of Physicians paediatric pain management guidelines. METHODS: The study was conducted as a single-site cross-sectional audit. One hundred and thirty-five patients (mean age 7.7 years) receiving treatment at the Royal Children's Hospital, Melbourne, Children's Cancer Centre Day Oncology Unit were observed. Procedural aspects related to the treatment room, carer and staff behaviour, child distress and use of pharmacologic and nonpharmacologic interventions were recorded using an audit tool developed for the study. RESULTS: The procedure room was regularly quiet and prepared before the child entered. Median procedure duration was 8 min. Median procedure wait time was 54 min. At least one carer was typically present during procedures. Comfort First (CF) clinicians were more likely to be present in procedures with a significantly distressed child. Carers, nurses and CF clinicians generally displayed comfort-promoting behaviour. Topical anaesthetic was regularly utilised. Nonpharmacologic supports were frequently used, particularly distraction. Patients under 8 years of age were significantly more likely to receive nonpharmacologic supports and have a carer and CF clinician present. Age was a significant predictor of distress, with higher distress rates in younger children. CONCLUSIONS: The CFP was found to be effectively implementing procedural pain guidelines. Regular audit is recommended to ensure adherence to pain management standards.