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Summary Introduction Methods Results Discussion Evidence to support intra‐operative lidocaine infusion regimens in patients with obesity is lacking, risking underdosing or toxicity. We aimed to measure the plasma concentrations of lidocaine and its active metabolites to develop a pharmacokinetic model and optimised dosing regimen in patients with obesity.A standardised weight‐based intravenous lidocaine regimen was administered to patients with a BMI ≥ 30 kg.m‐2 undergoing elective laparoscopic abdominal surgery. Using lean body weight, a 1.5 mg.kg‐1 loading dose over 10 min and infusion of 1.5 mg.kg‐1.h‐1 was administered intra‐operatively. Arterial blood was sampled during and after the infusion. The total and unbound plasma concentrations of lidocaine, monoethylglycinexylidide and glycinexylidide were measured using liquid chromatography‐mass spectrometry. Monolix was used for population pharmacokinetic analysis. Dosing simulations were performed using Simulx to develop a regimen that best targeted a therapeutic plasma concentration between 2.5 and 5 μg.ml‐1.Thirty patients provided 221 plasma samples (median (IQR [range]) age 51 (44–61 [32–76]) y and 21 female). Median (IQR [range]) total body weight was 107.0 (91.8–132.5 [80.0–189.0]) kg and BMI was 37.7 (33.6–46.5 [30.2–58.4]) kg.m‐2. Using total and unbound plasma concentrations of lidocaine, monoethylglycinexylidide and glycinexylidide, a four‐compartment model was developed. Unbound lidocaine volume of distribution was 2.1 l.kg‐1 and clearance 1.7 l.kg‐1.h‐1. Simulations showed that doses used currently had a low probability of target attainment of 0%. A loading dose of 2 mg.kg‐1 over 20 min followed by an infusion of 3 mg.kg‐1.h‐1 based on lean body weight improved probability of target attainment to 18.6%. The infusion should be reduced to 2 mg.kg‐1.h‐1 after 80 min.Our simulated dosing regimen achieved therapeutic concentrations more successfully in patients with obesity. Further studies should evaluate the clinical safety and efficacy of this dosing regimen. [ABSTRACT FROM AUTHOR]

A retrospective audit at Prince of Wales Hospital and Sydney Children's Hospital evaluated the impact of implementing a preoperative team huddle in theatre settings. The study found that the team huddle led to increased frequency of full multidisciplinary attendance, improving awareness, communication, and efficiency among staff. While there was a slight decrease in staff attitudes towards safety and teamwork, the team huddle was well-received and positively impacted theatre operations. The report, authored by a diverse group of individuals, emphasizes the importance of effective communication and teamwork in enhancing perioperative care. [Extracted from the article]

The coronavirus disease 2019 (COVID-19) pandemic in Australia resulted in significant additional infection control precautions for consumers and the health workforce. Prior to widespread vaccine availability, substantial changes were made to the operating theatre management of patients presenting for surgery with suspected or diagnosed COVID-19. This study aimed to calculate the actual costs of operating theatre care for patients with confirmed or suspected COVID-19. Data were prospectively collected for all patients presenting for surgery with confirmed or suspected COVID-19 at the Royal Brisbane and Women's Hospital. Information collected included patient characteristics, surgical and anaesthesia details, equipment, theatre utilisation, staffing and cleaning. The associated variable costs and usual costs of care were calculated according to the Australian National Efficient Price. We compared estimated usual costs with those estimated for patients with confirmed or suspected COVID-19. Twenty-four patients with suspected COVID-19 infection underwent surgery between May 2020 and February 2021. Cost analysis revealed a mean (standard deviation (SD), range) increase in costs of providing perioperative care for COVID-19 suspect patients of A$2252 (A$2570, A$315.85–10,398); that is, a mean of 207.5% more than usual care costs. This was primarily due to the increased number of staff and time required to complete these cases with appropriate infection control. [ABSTRACT FROM AUTHOR]

Patients undergoing elective pelvic exenteration surgery who receive piperacillin/tazobactam as surgical prophylaxis are at risk of suboptimal intraoperative antibiotic exposure. With this work, we aimed to study the plasma pharmacokinetics of piperacillin and tazobactam in this population to provide dosing recommendations that optimize antibiotic exposure. We developed a prospective, observational, pharmacokinetic study of piperacillin/tazobactam in patients undergoing pelvic exenteration. Population pharmacokinetic analysis and Monte Carlo simulations were performed with Monolix and Simulx software. Probabilities of target attainment of different dosing regimens against the minimum inhibitory concentration (MIC) breakpoints (8 and 16 mg/L) were calculated. Twelve patients were included in the study, with a median age of 50.0 years [interquartile interval (45.3-57.5)] and a median weight of 79.0 kg (61.3-88.3). Median surgical time was 10.5 h (9.8-11.7). A two-compartment linear model best fitted piperacillin and tazobactam data (190 plasma samples). Monte Carlo simulations showed that a lower dose of 2 g/0.25 g loading dose followed by 4 g/0.5 g q8h by continuous infusion provided ≥90% probability of target attainment for MIC = 16 mg/L for most of the patients. For non-continuous infusion regimens, only the 2-hourly bolus re-dosing achieved intraoperative concentrations of piperacillin ≥16 mg/L. Patients with weights ≥ 100 kg and glomerular filtration rates ≥ 120 mL/min required 4 g/0.5 g q6h by continuous infusion after a loading dose. In conclusion, continuous infusion of lower doses of piperacillin/tazobactam is as adequate as the 2-hourly re-dosing recommended by the current guidelines for surgical prophylaxis in pelvic exenteration. Patients with higher weights and glomerular filtration rates are at greater risk of inadequate exposure., Competing Interests: The authors declare no conflict of interest.