ABSTRACT
BACKGROUND: The longitudinal response to the COVID-19 vaccines among patients on hemodialysis with and without prior SARS-CoV-2 infection has not been well characterized. METHODS: To guide vaccination strategies in patients on hemodialysis, it is critical to characterize the longevity and efficacy of the vaccine; therefore, we conducted a prospective single-center monthly antibody surveillance study between March 2021 and March 2022 to investigate the dynamic humoral response to a series of COVID-19 mRNA vaccines in patients on hemodialysis with and without prior SARS-CoV-2 infection. Monthly quantitative antibody testing was performed using the Beckman Coulter Access SARS-CoV-2 IgG Antibody Test©, which detects IgG antibodies targeting the receptor binding domain (RBD) of the SARS-CoV-2 spike protein. RESULTS: This cohort of 30 participants (mean age: 61 ± 3 years) predominantly self-identified as African American (97%) and male (53%). Eight participants (27%) had recovered from COVID-19 (recovered) before the vaccine initiation. All participants received two vaccine doses, and 86.6% received a 6-month booster dose. Among patients naïve to COVID-19, the antibody positivity rate (APR) was 55% post-first-dose, 91% post-second-dose, 50% pre-booster at 6 months, 100% post-booster, and 89% at 6 months post-booster. Recovered patients sustained a consistent 100% APR throughout the year. The naïve patients demonstrated lower peak antibody levels post-second-dose than the recovered patients (17.9 ± 3.2 vs. 44.7 ± 5.6, p < 0.001). The peak antibody levels post-booster showed no significant difference between both groups (27.1 ± 3.9 vs. 37.9 ± 8.2, p = 0.20). Two naïve patients contracted COVID-19 during the follow-up period. CONCLUSIONS: The patients naïve to COVID-19 exhibited an attenuated and foreshortened antibody response following two doses of the mRNA vaccines compared with the recovered patients, who maintained 100% APR before the booster dose. The 6-month booster dose counteracted declining immunity and stimulated antibody responses in the naïve patients, even in previously non-responsive patients. This observation implies that different booster vaccination strategies might be required for COVID-19-naïve and -recovered patients. Post-vaccination antibody testing may serve as a valuable tool for guiding vaccination strategies.
ABSTRACT
BACKGROUND: The drug-eluting stents have decreased the incidence of instent restenosis compared to bare metal stents. But, the incidence of late and very late stent thrombosis has increased with the drug-eluting stents. CASE PRESENTATION: We are here, reporting three cases of incredibly late instent thrombosis, each one occurring after more than 50 months of drug-eluting stent placement. CONCLUSION: The occurrence of stent thrombosis as late as 5 years has been reported in literature. This highlights the importance that there may be no limit to the time duration to the occurrence of very late stent thrombosis and dual antiplatelet therapy with aspirin and clopidogrel may have to be continued indefinitely in patients with drug-eluting stents.
ABSTRACT
BACKGROUND: Patient-controlled analgesia is associated with potentially fatal opioid-related respiratory depression. Opioids are a well-recognized cause of respiratory depression. However, in the postoperative patient, unrecognized pulmonary disease may lead to retention of carbon dioxide, which is further antagonized by opioids and may lead to life-threatening respiratory depression. Therefore, using a method that would provide earlier warnings for respiratory problems could improve patient outcomes. OBJECTIVE: To assess the efficacy of monitoring postoperative patients who were receiving patient-controlled opioid therapy with capnography modules in addition to the routine use of pulse oximetry to monitor ventilatory status and generate alerts when respiratory parameters exceed hospital-established limits. METHOD: Postoperative patients receiving patient-controlled analgesia were compared in relation to the use of pulse oximetry and capnography modules and their ability to generate alerts about abnormal respiratory parameters. A total of 634 patients receiving patient-controlled analgesia therapy were studied, of whom 239 (38%) received hydromorphone, 297 (47%) received morphine, and 98 (15%) received fentanyl. All 9 patients experiencing respiratory depression received supplemental oxygen. RESULTS: Of the 634 patients studied, 9 (1.4%) experienced respiratory depression by bradypnea (<6 breaths per minute). Six (67%) events were related to hydromorphone and 3 (33%) were related to morphine. In 7 (78%) events, there was no basal infusion rate and the saturation of peripheral oxygen was >92%. All respiratory depression events occurred within the first 24 hours of patient-controlled analgesia therapy. In all cases, capnography, but not pulse oximetry, alerted the nurse to impending respiratory depression. CONCLUSIONS: Capnography was more effective than pulse oximetry in providing early warning of respiratory depression in patients receiving supplemental oxygen. Capnographic monitoring and automatic pausing of patient-controlled analgesia improved postoperative outcomes in situations that could have otherwise been fatal. Use of capnography improved clinician confidence that opioid dosing could be safely continued in postoperative patients for more effective pain management.
