Pharmacokinetics of meropenem in critically ill patients in Saudi Arabia

Background

Meropenem is commonly used in the ICU to treat gram-negative infections. Due to various pathophysiological changes, critically ill patients are at higher risk of having subtherapeutic concentrations and hence have a higher risk of treatment failure—especially in regions where gram-negative drug resistance is increasing, such as Saudi Arabia. No studies have evaluated the pharmacokinetics of meropenem in critically ill patients in Saudi Arabia. Our primary objective is to assess the percentage of patients achieving the therapeutic target for meropenem.

Methods

This prospective observational study was conducted in the ICUs of King Khalid University Hospital. Patient were included if >18 years-of-age and received meropenem for a clinically suspected or proven bacterial infection. The primary outcome was to assess the percentage of patients who achieved the pharmacokinetic/pharmacodynamic (PKPD) therapeutic target of a free trough concentration four times the MIC. The secondary outcome was to estimate the pharmacokinetics of meropenem. Pharmacokinetic analysis was performed using Monolix Suite 2020R1 (Lixoft, France).

Results

Trough concentrations were highly variable and ranged from <0.5 µg/mL to 39 µg/mL, with a mean ± SD trough concentration of 8.5 ± 8 µg/mL. Only 46% of patients achieved the therapeutic target. The only significant predictor of failing to achieve the PKPD target was augmented renal clearance.

Conclusion

In conclusion, more than half of our patients did not achieve the PKPD target. Thus, there is a need for better dosing strategies of meropenem in critically ill patients in Saudi Arabia such as extended and continuous infusion.

Assessment of anti-factor Xa activity in critically ill COVID-19 patients receiving three different anticoagulation regimens

INTRODUCTION

Critically ill COVID-19 patients are at increased risk of thrombosis with an enhanced risk of bleeding. We aimed to explore the role of anti-factor Xa levels in optimizing the high-intensity anticoagulation's safety and efficacy and finding possible associations between D-dimer levels, cytokine storm markers, and COVID-19-induced coagulopathy or thrombophilia.

METHODS

Retrospective cohort study conducted on 69 critically ill COVID-19 patients who received three regimens of higher intensity anticoagulation.

RESULTS

Seventeen patients (24.6%) received high-dose enoxaparin prophylaxis, 29 patients (42%) received therapeutic doses of enoxaparin, and 23 patients (33.3%) were on therapeutic unfractionated heparin infusion. Fewer than one-third of the whole cohort (n = 22; 31.8%) achieved the target range of anti-factor Xa. The patients were divided into three subgroups based on anti-factor Xa target status within each anticoagulation regimen; when compared, the only association observed among them was for interleukin-6 levels, which were significantly higher in both the "above the expected range" and "below the expected range" groups compared with the "within the expected range" group (p = 0.009). Major bleeding episodes occurred in 14 (20.3%) patients and were non-significantly more frequent in the "below the expected anti-factor Xa range group" (p = 0.415). Seven patients (10.1%) developed thrombosis. The majority of patients had anti-factor Xa levels below the expected ranges (four patients, 57.1%).

CONCLUSION

Conventional anti-factor Xa ranges may not be appropriate as a predictive surrogate for bleeding in critically ill COVID-19. The clinical decision to initiate therapeutic anticoagulation preemptively may be individualized according to thrombosis and bleeding risks. Cytokine storm markers, namely, interleukin-6, may play a role in COVID-19-induced coagulopathy or thrombophilia.

External Validation of Obese/Critically Ill Vancomycin Population Pharmacokinetic Models in Critically Ill Patients Who Are Obese

Obesity combined with critical illness might increase the risk of acquiring infections and hence mortality. In this patient population the pharmacokinetics of antimicrobials vary significantly, making antimicrobial dosing challenging. The objective of this study was to assess the predictive performance of published population pharmacokinetic models of vancomycin in patients who are critically ill or obese for a cohort of critically ill patients who are obese. This was a multi-center retrospective study conducted at 2 hospitals. Adult patients with a body mass index of ≥30 kg/m2 were included. PubMed was searched for published population pharmacokinetic studies in patients who were critically ill or obese. External validation was performed using Monolix software. A total of 4 models were identified in patients who were obese and 5 models were identified in patients who were critically ill. In total, 138 patients who were critically ill and obese were included, and the most accurate models for these patients were the Goti and Roberts models. In our analysis, models in patients who were critically ill outperformed models in patients who were obese. When looking at the most accurate models, both the Goti and the Roberts models had patient characteristics similar to ours in terms of age and creatinine clearance. This indicates that when selecting the proper model to apply in practice, it is important to account for all relevant variables, besides obesity.

Monkeypox Disease (MPOX) Perceptions among Healthcare Workers versus General Population during the First Month of the WHO Alert: Cross-Sectional Survey in Saudi Arabia

Background: Monkeypox disease (MPOX) recently re-emerged in May 2022, causing international outbreaks in multiple non-endemic countries. This study demonstrates a novel comparison between the knowledge and perceptions of Saudi healthcare workers (HCWs) and the general public regarding MPOX. Methods: An online survey, conducted from 27 May to 5 June 2022, assessing participants' MPOX and monkeypox virus (MPV) knowledge in terms of transmission, vaccination, isolation precautions, and their attitudes toward seeking more information. Results: A total of 1546 members of the public and 1130 HCWs completed the survey. Briefly, 61.3% of the public and 74.2% of HCWs showed interest in seeking more information about MPOX. Both groups had average overall mean MPOX knowledge scores. Members of the public holding university degrees and those showing high levels of worry regarding MPOX had significantly higher knowledge scores. However, HCWs showed a poor vaccination knowledge score, while only 57% recognized that MPOX can present similarly to COVID-19 in the early stages. Female HCWs and those with high self-rated MPOX awareness had significantly high knowledge scores. HCWs in secondary and tertiary centers had significantly higher knowledge scores. Conclusion: Both groups showed a decent attitude in terms of seeking more MPOX knowledge, which correlated positively with their worry about and awareness of the disease. These observations are mostly as a consequence of the ongoing COVID-19 pandemic, which encouraged the public and HCW to acquire more information about any novel emerging disease. Policymakers should make the most of this attitude in their awareness campaigns to prevent the spread of the disease and encourage vaccination in cases where it is needed. The knowledge gaps among HCWs were most evident in terms of clinical presentation and vaccinations; this problem needs addressing if we are to avoid further emerging MPOX cases.