Pre-operative prevalence of asymptomatic carriers of COVID-19 in hospitals in Catalonia during the first wave after the resumption of surgical activity.

INTRODUCTION: The COVID-19 pandemic led to the cancellation of non-essential surgical procedures in March 2020. With the resumption of surgical activity, patients undergoing surgery were one of the first population groups to be systematically tested for PCR. The aim of this study was to determine the prevalence of asymptomatic SARS-CoV-2 carriers after the resumption of non-essential surgical activity. METHODS: Retrospective multicenter observational study of patients scheduled for surgery or undergoing emergency surgery in Catalonia between 20 April and 31 May 2020. The microbiological results of preoperative PCR tests and clinical records were reviewed, and an epidemiological survey was conducted on patients with positive PCR for SARS-CoV-2. RESULTS: A total of 10,838 patients scheduled for surgery or who underwent emergency surgery were screened for COVID-19. One hundred and eighteen patients (1.09%) were positive for SARS-CoV-2 in the 72 h prior to surgery. The prevalence of asymptomatic carriers was 0.7% (IC95%: 0.6%-0.9%). The first week of the study presented the highest prevalence of asymptomatic carriers [1.9% (CI95%:1.1%-3.2%)]. CONCLUSIONS: The low levels of asymptomatic carriers of COVID-19 infection obtained in the surgical population of hospitals in Catalonia after the resumption of surgical activity, shows that most patients were able to undergo surgical procedures without the risks of COVID-19 associated complications in the perioperative period.

Pre-operative prevalence of asymptomatic carriers of COVID-19 in hospitals in Catalonia during the first wave after the resumption of surgical activity. / Prevalencia preoperatoria de portadores asintomáticos de COVID-19 en hospitales de Cataluña durante la primera ola tras el reinicio de la actividad quirúrgica.

INTRODUCTION: The COVID-19 pandemic led to the cancellation of non-essential surgical procedures in March 2020. With the resumption of surgical activity, patients undergoing surgery were one of the first population groups to be systematically tested for PCR. The aim of this study was to determine the prevalence of asymptomatic SARS-CoV-2 carriers after the resumption of non-essential surgical activity. METHODS: Retrospective multicenter observational study of patients scheduled for surgery or undergoing emergency surgery in Catalonia between 20 April and 31 May 2020. The microbiological results of preoperative PCR tests and clinical records were reviewed, and an epidemiological survey was conducted on patients with positive PCR for SARS-CoV-2. RESULTS: A total of 10,838 patients scheduled for surgery or who underwent emergency surgery were screened for COVID-19. One hundred and eighteen patients (1.09%) were positive for SARS-CoV-2 in the 72hours prior to surgery. The prevalence of asymptomatic carriers was 0.7% (95%CI: 0.6% - 0.9%). The first week of the study presented the highest prevalence of asymptomatic carriers [1.9% (95%CI: 1.1%-3.2%)]. CONCLUSIONS: The low levels of asymptomatic carriers of COVID-19 infection obtained in the surgical population of hospitals in Catalonia after the resumption of surgical activity, shows that most patients were able to undergo surgical procedures without the risks of COVID-19 associated complications in the perioperative period.

Is the pharmacokinetics of bupivacaine equivalent after lumbar epidural administration through a needle or a catheter in male and female adults?

We assessed possible pharmacokinetic modifications due to different epidural injection techniques using either a needle or a catheter. Adult patients (n=23) undergoing lower abdominal or lower extremity surgery were randomly assigned a single bupivacaine epidural injection anesthesia (0.5%, 15 mL, 0.3 mL/s) through needle or catheter device. Plasma bupivacaine concentration was quantified using a validated HPLC method and non-compartmental pharmacokinetic parameters estimated. CMAX and TMAX were similar in both groups: 952 ± 346 ng/mL, 0.65 ± 0.5 1h in the needle group; 810 ± 307 ng/mL, 0.43 ± 0.29 h in the catheter group respectively. Plasma AUC0→∞ was also similar in both groups: 3868 ± 1687 ngh/mL for needle versus 4096 ± 1748 ngh/mL using catheter. The catheter group showed slower disposition than the needle group: t1/2=3.9 ± 2.3 h, MRT=6.0 ± 3.1 h versus 2.7 ± 1.03 h and 4.5 ± 1.2 h with needle administration respectively though it did not reach statistical significance, Cl/F and V/F were also similar. Lastly, female patients showed significant longer t1/2 after administration through catheter (5.7 ± 2.0 h) than needle (2.7 ± 0.6 h) group (P=0.0279). The device type does not affect the pharmacokinetics which is similar in both groups although sex-based differences might exist.

Pharmacodynamic approach to immunosuppressive therapies using calcineurin inhibitors and mycophenolate mofetil.

BACKGROUND: Graft survival depends on adequate immunosuppression. To evaluate the effect on the immune system of immunosuppressive therapies using calcineurin inhibitors (CNIs), several pharmacodynamic indices have been proposed to complement pharmacokinetic data. In this preliminary study we compared some of these parameters during combined immunosuppressant therapies. METHODS: We treated 65 stable renal transplant recipients with cyclosporin A (CsA; n = 16), tacrolimus (TRL; n = 10); CsA + mycophenolate mofetil (MMF; n = 14); TRL + MMF (n = 13), and MMF (n = 12). Twelve nontreated healthy controls were also included. Calcineurin activity (CNA) in peripheral blood mononuclear cells was measured using (32)P-labeled peptide. Interleukin-2 (IL-2) and interferon-gamma production in phytohemagglutinin-activated whole blood were measured at 0 and 2 h postdose. The areas under the curves, c(min), c(max), and concentration at 2 h (c(2 h)) were also measured. RESULTS: We found no differences in CNA between groups receiving CNIs alone or combined with MMF [median (25th-75th percentiles)]: CsA(2 h), 3.87 (3.00-6.85)% alkaline phosphatase (AP); CsA+MMF(2 h), 3.90 (1.78-5.19)% AP; TRL(2 h), 5.68 (3.02-16.00)% AP; TRL+MMF(2 h), 11.80 (4.05-14.63)% AP. In vitro IL-2 production was significantly lower in the groups receiving combined therapy than in groups receiving CNIs alone [median (25th-75th percentiles)]: CsA(2 h), 276.52 (190.41-385.25) ng/L; CsA+MMF(2 h), 166.48 (81.06-377.01) ng/L (P <0.001); TRL(2 h), 249.34 (127.48-363.50) ng/L; TRL+ MMF(2 h), 122.13 (51.02-180.00) ng/L (P <0.001). The correlations (r) between c(2 h) and CNA 2 h postdose were as follows: CsA, r = -0.74; CsA+MMF, r = -0.84; TRL, r = -0.70; TRL+ MMF, r = -0.70 (P <0.001 in all cases). CONCLUSIONS: The measurement of CNA may be of help in following the effect on the immune system of CNI treatments, even in combined therapies, but does not reflect the additional effect of MMF. In contrast, IL-2 in vitro production reflects the effect of both MMF and CNIs.