Effectiveness of a bivalent mRNA vaccine dose against symptomatic SARS-CoV-2 infection among U.S. Healthcare personnel, September 2022-May 2023

BACKGROUND

Bivalent mRNA vaccines were recommended since September 2022. However, coverage with a recent vaccine dose has been limited, and there are few robust estimates of bivalent VE against symptomatic SARS-CoV-2 infection (COVID-19). We estimated VE of a bivalent mRNA vaccine dose against COVID-19 among eligible U.S. healthcare personnel who had previously received monovalent mRNA vaccine doses.

METHODS

We conducted a case-control study in 22 U.S. states, and enrolled healthcare personnel with COVID-19 (case-participants) or without COVID-19 (control-participants) during September 2022-May 2023. Participants were considered eligible for a bivalent mRNA dose if they had received 2-4 monovalent (ancestral-strain) mRNA vaccine doses, and were ≥67 days after the most recent vaccine dose. We estimated VE of a bivalent mRNA dose using conditional logistic regression, accounting for matching by region and four-week calendar period. We adjusted estimates for age group, sex, race and ethnicity, educational level, underlying health conditions, community COVID-19 exposure, prior SARS-CoV-2 infection, and days since the last monovalent mRNA dose.

RESULTS

Among 3,647 healthcare personnel, 1,528 were included as case-participants and 2,119 as control-participants. Participants received their last monovalent mRNA dose a median of 404 days previously; 1,234 (33.8%) also received a bivalent mRNA dose a median of 93 days previously. Overall, VE of a bivalent dose was 34.1% (95% CI, 22.6%-43.9%) against COVID-19 and was similar by product, days since last monovalent dose, number of prior doses, age group, and presence of underlying health conditions. However, VE declined from 54.8% (95% CI, 40.7%-65.6%) after 7-59 days to 21.6% (95% CI 5.6%-34.9%) after ≥60 days.

CONCLUSIONS

Bivalent mRNA COVID-19 vaccines initially conferred approximately 55% protection against COVID-19 among U.S. healthcare personnel. However, protection waned after two months. These findings indicate moderate initial protection against symptomatic SARS-CoV-2 infection by remaining up-to-date with COVID-19 vaccines.

Ramipril for the Treatment of COVID-19: RAMIC, a Randomized, Double-Blind, Placebo-Controlled Clinical Trial

INTRODUCTION

Retrospective studies report that angiotensin-converting enzyme inhibitors (ACEIs) may reduce the severity of COVID-19, but prospective data on de novo treatment with ACEIs are limited. The RAMIC trial was a randomized, multicenter, placebo-controlled, double-blind, allocation-concealed clinical trial to examine the efficacy of de novo ramipril versus placebo for the treatment of COVID-19.

METHODS

Eligible participants were aged 18 years and older with a confirmed diagnosis of SARS-CoV-2 infection, recruited from urgent care clinics, emergency departments, and hospital inpatient wards at eight sites in the USA. Participants were randomly assigned to daily ramipril 2.5 mg or placebo orally in a 2:1 ratio, using permuted block randomization. Analyses were conducted on an intention-to-treat basis. The primary outcome was a composite of mortality, intensive care unit (ICU) admission, or invasive mechanical ventilation by day 14.

RESULTS

Between 27 May 2020 and 19 April 2021, a total of 114 participants (51% female) were randomized to ramipril (n = 79) or placebo (n = 35). The overall mean (± SD) age and BMI were 45 (± 15) years and 33 (± 8) kg/m2. Two participants in the ramipril group required ICU admission and one died, compared with none in the placebo group. There were no significant differences between ramipril and placebo in the primary endpoint (ICU admission, mechanical ventilation, or death) (3% versus 0%, p = 1.00) or adverse events (27% versus 29%, p = 0.82). The study was terminated early because of a low event rate and subsequent Emergency Use Authorization of therapies for COVID-19.

CONCLUSION

De novo ramipril was not different compared with placebo in improving or worsening clinical outcomes from COVID-19 but appeared safe in non-critically ill patients with COVID-19.

TRIAL REGISTRATION

Clinicaltrials.gov NCT04366050.

Effectiveness of a Messenger RNA Vaccine Booster Dose Against Coronavirus Disease 2019 Among US Healthcare Personnel, October 2021-July 2022

Background

Protection against symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (coronavirus disease 2019 [COVID-19]) can limit transmission and the risk of post-COVID conditions, and is particularly important among healthcare personnel. However, lower vaccine effectiveness (VE) has been reported since predominance of the Omicron SARS-CoV-2 variant.

Methods

We evaluated the VE of a monovalent messenger RNA (mRNA) booster dose against COVID-19 from October 2021 to June 2022 among US healthcare personnel. After matching case-participants with COVID-19 to control-participants by 2-week period and site, we used conditional logistic regression to estimate the VE of a booster dose compared with completing only 2 mRNA doses >150 days previously, adjusted for multiple covariates.

Results

Among 3279 case-participants and 3998 control-participants who had completed 2 mRNA doses, we estimated that the VE of a booster dose against COVID-19 declined from 86% (95% confidence interval, 81%-90%) during Delta predominance to 65% (58%-70%) during Omicron predominance. During Omicron predominance, VE declined from 73% (95% confidence interval, 67%-79%) 14-60 days after the booster dose, to 32% (4%-52%) ≥120 days after a booster dose. We found that VE was similar by age group, presence of underlying health conditions, and pregnancy status on the test date, as well as among immunocompromised participants.

Conclusions

A booster dose conferred substantial protection against COVID-19 among healthcare personnel. However, VE was lower during Omicron predominance, and waning effectiveness was observed 4 months after booster dose receipt during this period. Our findings support recommendations to stay up to date on recommended doses of COVID-19 vaccines for all those eligible.

Facemasks: Perceptions and use in an ED population during COVID-19

Study objective

Facemask use is associated with reduced transmission of SARS-CoV-2. Most surveys assessing perceptions and practices of mask use miss the most vulnerable racial, ethnic, and socio-economic populations. These same populations have suffered disproportionate impacts from the pandemic. The purpose of this study was to assess beliefs, access, and practices of mask wearing across 15 urban emergency department (ED) populations.

Methods

This was a secondary analysis of a cross-sectional study of ED patients from December 2020 to March 2021 at 15 geographically diverse, safety net EDs across the US. The primary outcome was frequency of mask use outside the home and around others. Other outcome measures included having enough masks and difficulty obtaining them.

Results

Of 2,575 patients approached, 2,301 (89%) agreed to participate; nine had missing data pertaining to the primary outcome, leaving 2,292 included in the final analysis. A total of 79% of respondents reported wearing masks “all of the time” and 96% reported wearing masks over half the time. Subjects with PCPs were more likely to report wearing masks over half the time compared to those without PCPs (97% vs 92%). Individuals experiencing homelessness were less likely to wear a mask over half the time compared to those who were housed (81% vs 96%).

Conclusions

Study participants reported high rates of facemask use. Respondents who did not have PCPs and those who were homeless were less likely to report wearing a mask over half the time and more likely to report barriers in obtaining masks. The ED may serve a critical role in education regarding, and provision of, masks for vulnerable populations.

Effectiveness of mRNA Covid-19 Vaccine among U.S. Health Care Personnel

BACKGROUND

The prioritization of U.S. health care personnel for early receipt of messenger RNA (mRNA) vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (Covid-19), allowed for the evaluation of the effectiveness of these new vaccines in a real-world setting.

METHODS

We conducted a test-negative case-control study involving health care personnel across 25 U.S. states. Cases were defined on the basis of a positive polymerase-chain-reaction (PCR) or antigen-based test for SARS-CoV-2 and at least one Covid-19-like symptom. Controls were defined on the basis of a negative PCR test for SARS-CoV-2, regardless of symptoms, and were matched to cases according to the week of the test date and site. Using conditional logistic regression with adjustment for age, race and ethnic group, underlying conditions, and exposures to persons with Covid-19, we estimated vaccine effectiveness for partial vaccination (assessed 14 days after receipt of the first dose through 6 days after receipt of the second dose) and complete vaccination (assessed ≥7 days after receipt of the second dose).

RESULTS

The study included 1482 case participants and 3449 control participants. Vaccine effectiveness for partial vaccination was 77.6% (95% confidence interval [CI], 70.9 to 82.7) with the BNT162b2 vaccine (Pfizer-BioNTech) and 88.9% (95% CI, 78.7 to 94.2) with the mRNA-1273 vaccine (Moderna); for complete vaccination, vaccine effectiveness was 88.8% (95% CI, 84.6 to 91.8) and 96.3% (95% CI, 91.3 to 98.4), respectively. Vaccine effectiveness was similar in subgroups defined according to age (<50 years or ≥50 years), race and ethnic group, presence of underlying conditions, and level of patient contact. Estimates of vaccine effectiveness were lower during weeks 9 through 14 than during weeks 3 through 8 after receipt of the second dose, but confidence intervals overlapped widely.

CONCLUSIONS

The BNT162b2 and mRNA-1273 vaccines were highly effective under real-world conditions in preventing symptomatic Covid-19 in health care personnel, including those at risk for severe Covid-19 and those in racial and ethnic groups that have been disproportionately affected by the pandemic. (Funded by the Centers for Disease Control and Prevention.).

Self-obtained vaginal swabs are not inferior to provider-performed endocervical sampling for emergency department diagnosis of Neisseria gonorrhoeae and Chlamydia trachomatis

OBJECTIVE

Provider-performed endocervical sampling (PPES) in the diagnosis of Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) may be difficult to perform in a busy emergency department (ED) due to patient preference, availability of the pelvic examination room, or provider availability. Our objective was to assess if self-obtained vaginal swabs (SOVS) were noninferior to PPES in the ED diagnosis of NG/CT using a rapid nucleic acid amplification test (NAAT).

METHODS

We conducted a prospective observational cohort study in a single ED. Participants were adult female English- and Spanish-speaking patients in whom the ED provider felt that NG/CT testing was warranted. Each patient had SOVS and PPES performed. For SOVS, a research associate reviewed a one-page handout describing the procedure but gave no other assistance. Patients answered survey questions regarding acceptability of SOVS and symptomatology. We established a minimum sensitivity of 90% for SOVS to be considered clinically noninferior to standard PPES.

RESULTS

A total of 533 patients completed enrollment and answered survey questions, 515 of whom had laboratory results for both SOVS and PPES. There were 86 patients with a positive result: 29 with NG, 47 with CT, and 10 with coinfection. SOVS had a sensitivity of 95% (95% confidence interval = 88% to 99%) for the detection of NG/CT when compared to PPES. SOVS were felt to be an acceptable collection method in 93% of patients and 75% preferred SOVS to PPES.

CONCLUSION

SOVS are noninferior to PPES in NG/CT diagnosis using a rapid NAAT in ED patients and surveys indicate high patient acceptability.

The Rapid Evaluation of COVID-19 Vaccination in Emergency Departments for Underserved Patients Study

Study objective

Emergency departments (EDs) often serve vulnerable populations who may lack primary care and have suffered disproportionate COVID-19 pandemic effects. Comparing patients having and lacking a regular source of medical care and other ED patient characteristics, we assessed COVID-19 vaccine hesitancy, reasons for not wanting the vaccine, perceived access to vaccine sites, and willingness to get the vaccine as part of ED care.

Methods

This was a cross-sectional survey conducted from December 10, 2020, to March 7, 2021, at 15 safety net US EDs. Primary outcomes were COVID-19 vaccine hesitancy, reasons for vaccine hesitancy, and sites (including EDs) for potential COVID-19 vaccine receipt.

Results

Of 2,575 patients approached, 2,301 (89.4%) participated. Of the 18.4% of respondents who lacked a regular source of medical care, 65% used the ED as their usual source of health care. The overall rate of vaccine hesitancy was 39%; the range among the 15 sites was 28% to 58%. Respondents who lacked a regular source of medical care were more commonly vaccine hesitant than those who had a regular source of medical care (47% versus 38%, 9% difference, 95% confidence interval 4% to 14%). Other characteristics associated with greater vaccine hesitancy were younger age, female sex, Black race, Latinx ethnicity, and not having received an influenza vaccine in the past 5 years. Of the 61% who would accept a COVID-19 vaccine, 21% stated that they lacked a primary physician or clinic at which to receive it; the vast majority (95%) of these respondents would accept the COVID-19 vaccine as part of their care in the ED.

Conclusion

ED patients who lack a regular source of medical care are particularly hesitant regarding COVID-19 vaccination. Most COVID-19 vaccine acceptors would accept it as part of their care in the ED. EDs may play pivotal roles in COVID-19 vaccine messaging and delivery to highly vulnerable populations.

Emergency physician stressors, concerns, and behavioral changes during COVID-19: A longitudinal study

Objectives

The objective was to provide a longitudinal assessment of anxiety levels and work and home concerns of U.S. emergency physicians during the COVID‐19 pandemic.

Methods

We performed a longitudinal, cross‐sectional email survey of clinically active emergency physicians (attending, fellow, and resident) at seven academic emergency departments. Follow‐up surveys were sent 4 to 6 weeks after the initial survey and assessed the following: COVID‐19 patient exposure, availability of COVID‐19 testing, levels of home and workplace anxiety/stress, changes in behaviors, and performance on a primary care posttraumatic stress disorder screen (PC‐PTSD‐5). Logistic regression explored factors associated with a high PC‐PTSD‐5 scale score (≥3), indicating increased risk for PTSD.

Results

Of the 426 surveyed initial respondents, 262 (61.5%) completed the follow‐up survey. While 97.3% (255/262) reported treating suspected COVID‐19 patients, most physicians (162/262, 61.8%) had not received testing themselves. In follow‐up, respondents were most concerned about the relaxing of social distancing leading to a second wave (median score = 6, IQR = 4–7). Physicians reported a consistently high ability to order COVID‐19 tests for patients (median score = 6, IQR = 5–7) and access to personal protective equipment (median score = 6, IQR = 5–6). Women physicians were more likely to score ≥ 3 than men on the PC‐PTSD‐5 screener on the initial survey (43.3% vs. 22.5%; Δ 20.8%, 95% confidence interval [CI] = 9.3% to 31.5%), and despite decreases in overall proportions, this discrepancy remained in follow‐up (34.7% vs. 16.8%; Δ 17.9%, 95% CI = 7.1% to 28.1%). In examining the relationship between demographics, living situations, and institution location on having a PC‐PTSD‐5 score ≥ 3, only female sex was associated with a PC‐PTSD‐5 score ≥ 3 (adjusted odds ratio = 2.48, 95% CI = 1.28 to 4.79).

Conclusions

While exposure to suspected COVID‐19 patients was nearly universal, stress levels in emergency physicians decreased with time. At both initial and follow‐up assessments, women were more likely to test positive on the PC‐PTSD‐5 screener compared to men.

Academic Emergency Medicine Physicians' Anxiety Levels, Stressors, and Potential Stress Mitigation Measures During the Acceleration Phase of the COVID-19 Pandemic

Objective

The objective was to assess anxiety and burnout levels, home life changes, and measures to relieve stress of U.S. academic emergency medicine (EM) physicians during the COVID‐19 pandemic acceleration phase.

Methods

We sent a cross‐sectional e‐mail survey to all EM physicians at seven academic emergency departments. The survey incorporated items from validated stress scales and assessed perceptions and key elements in the following domains: numbers of suspected COVID‐19 patients, availability of diagnostic testing, levels of home and workplace anxiety, severity of work burnout, identification of stressors, changes in home behaviors, and measures to decrease provider anxiety.

Results

A total of 426 (56.7%) EM physicians responded. On a scale of 1 to 7 (1 = not at all, 4 = somewhat, and 7 = extremely), the median (interquartile range) reported effect of the pandemic on both work and home stress levels was 5 (4–6). Reported levels of emotional exhaustion/burnout increased from a prepandemic median (IQR) of 3 (2–4) to since the pandemic started a median of 4 (3–6), with a difference in medians of 1.8 (95% confidence interval = 1.7 to 1.9). Most physicians (90.8%) reported changing their behavior toward family and friends, especially by decreasing signs of affection (76.8%). The most commonly cited measures cited to alleviate stress/anxiety were increasing personal protective equipment (PPE) availability, offering rapid COVID‐19 testing at physician discretion, providing clearer communication about COVID‐19 protocol changes, and assuring that physicians can take leave for care of family and self.

Conclusions

During the acceleration phase, the COVID‐19 pandemic has induced substantial workplace and home anxiety in academic EM physicians, and their exposure during work has had a major impact on their home lives. Measures cited to decrease stress include enhanced availability of PPE, rapid turnaround testing at provider discretion, and clear communication about COVID‐19 protocol changes.

Sensitivity of a bedside reagent strip for the detection of spontaneous bacterial peritonitis in ED patients with ascites

STUDY OBJECTIVE

To determine the sensitivity of a highly sensitive bedside leukocyte esterase reagent strip (RS) for detection of spontaneous bacterial peritonitis (SBP) in emergency department (ED) ascites patients undergoing paracentesis.

METHODS

We conducted a prospective, observational cohort study of ED ascites patients undergoing paracentesis at two academic facilities. Two practitioners, blinded to each other's results, did a bedside RS analysis of the peritoneal fluid in each patient and documented the RS reading at 3-min according to manufacturer-specified colorimetric strip reading as either "negative", "trace", "small", or "large". The primary outcome measure was sensitivity of the RS strip for SBP (absolute neutrophil count ≥ 250 cells/mm³) at the "trace" threshold (positive equals trace or greater).

RESULTS

There were 330 cases enrolled, with 635 fluid analyses performed. Of these, 40 fluid samples had SBP (6%). Bedside RS had a sensitivity, specificity, positive predictive value, and negative predictive value of 95% (95% CI 82%-99%), 48% (95% CI 44%-52%), 11% (95% CI 10%-11%), and 99% (95% CI 97%-99%) respectively at the "trace" threshold for the detection of SBP.

CONCLUSION

Bedside use of the RS in ED ascites patients demonstrated high sensitivity for SBP. Given the wide confidence intervals, we cannot currently recommend it as a stand-alone test. We recommend further study with a larger number of SBP patients, potentially combining a negative RS result with low clinical suspicion to effectively rule out SBP without formal laboratory analysis.

Clinical impression and ascites appearance do not rule out bacterial peritonitis

BACKGROUND

Previous research has demonstrated that physician clinical suspicion, determined without assessing fluid appearance, is not adequate to rule out spontaneous bacterial peritonitis (SBP) without fluid testing.

STUDY OBJECTIVE

To determine the sensitivity of physician clinical suspicion, including a bedside assessment of fluid appearance, in the detection of SBP in Emergency Department (ED) patients undergoing paracentesis.

METHODS

We conducted a prospective, observational study of ED patients with ascites undergoing paracentesis at three academic facilities. The enrolling physician recorded the clinical suspicion of SBP ("none," "low," "moderate," or "high"), and ascites appearance ("clear," "hazy," "cloudy," or "bloody"). SBP was defined as an absolute neutrophil count ≥ 250 cells/mm(3), or culture pathogen growth. We defined "clear" ascites fluid as negative for SBP, and "hazy," "cloudy," or "bloody" as positive. A physician clinical suspicion of "none" or "low" was considered negative for SBP, and an assessment of "moderate" or "high" was considered positive. The primary outcome measure was sensitivity of physician clinical impression and ascites appearance for SBP.

RESULTS

There were 348 cases enrolled, with SBP diagnosed in 43 (12%). Physician clinical suspicion had a sensitivity of 42% (95% confidence interval [CI] 29-55%) for the detection of SBP. Fluid appearance had a sensitivity of 72% (95% CI 58-83%).

CONCLUSION

Physician clinical impression, which included an assessment of fluid appearance, had poor sensitivity for the detection of SBP and cannot be used to exclude the diagnosis. Routine laboratory fluid analysis is indicated after ED paracentesis, even in patients considered to have a low degree of suspicion for SBP.

A comparison of GlideScope video laryngoscopy versus direct laryngoscopy intubation in the emergency department

OBJECTIVES

The first-attempt success rate of intubation was compared using GlideScope video laryngoscopy and direct laryngoscopy in an emergency department (ED).

METHODS

A prospective observational study was conducted of adult patients undergoing intubation in the ED of a Level 1 trauma center with an emergency medicine residency program. Patients were consecutively enrolled between August 2006 and February 2008. Data collected included indication for intubation, patient characteristics, device used, initial oxygen saturation, and resident postgraduate year. The primary outcome measure was success with first attempt. Secondary outcome measures included time to successful intubation, intubation failure, and lowest oxygen saturation levels. An attempt was defined as the introduction of the laryngoscope into the mouth. Failure was defined as an esophageal intubation, changing to a different device or physician, or inability to place the endotracheal tube after three attempts.

RESULTS

A total of 280 patients were enrolled, of whom video laryngoscopy was used for the initial intubation attempt in 63 (22%) and direct laryngoscopy was used in 217 (78%). Reasons for intubation included altered mental status (64%), respiratory distress (47%), facial trauma (9%), and immobilization for imaging (9%). Overall, 233 (83%) intubations were successful on the first attempt, 26 (9%) failures occurred, and one patient received a cricothyrotomy. The first-attempt success rate was 51 of 63 (81%, 95% confidence interval [CI] = 70% to 89%) for video laryngoscopy versus 182 of 217 (84%, 95% CI = 79% to 88%) for direct laryngoscopy (p = 0.59). Median time to successful intubation was 42 seconds (range, 13 to 350 seconds) for video laryngoscopy versus 30 seconds (range, 11 to 600 seconds) for direct laryngoscopy (p < 0.01).

CONCLUSIONS

Rates of successful intubation on first attempt were not significantly different between video and direct laryngoscopy. However, intubation using video laryngoscopy required significantly more time to complete.

Physician clinical impression does not rule out spontaneous bacterial peritonitis in patients undergoing emergency department paracentesis

STUDY OBJECTIVE

We determine whether clinical characteristics and physician assessment are useful in the exclusion of spontaneous bacterial peritonitis in emergency department (ED) patients with ascites requiring paracentesis.

METHODS

We conducted a prospective, observational study of ED patients with ascites undergoing paracentesis. Predefined clinical characteristics including historical features and ED vital signs were recorded. Each patient was assessed by 2 separate, blinded physicians for severity of abdominal tenderness and overall clinical suspicion for spontaneous bacterial peritonitis. The primary outcome measures were sensitivity, specificity, and likelihood ratios (LR) of the individual clinical characteristics and the physician assessments. Spontaneous bacterial peritonitis was defined by absolute neutrophil count greater than 250 cells/mm(3) or positive fluid culture result.

RESULTS

There were 285 separate physician assessments in 144 patients enrolled with complete data. Spontaneous bacterial peritonitis was diagnosed in 17 (11.8%) patients. Physician clinical impression had a sensitivity of 76% (95% confidence interval [CI] 62% to 91%) and specificity of 34% (95% CI 28% to 40%) for the detection of spontaneous bacterial peritonitis. The lowest negative LR was associated with the presence of any abdominal pain or tenderness (negative LR=0.4); however, the presence of pain/tenderness was also observed in 85% of patients without spontaneous bacterial peritonitis. Six patients (4.2%) with spontaneous bacterial peritonitis had at least 1 physician assessment of little to no risk for spontaneous bacterial peritonitis, and 3 of the 6 subsequently died during their hospitalization.

CONCLUSION

Clinical characteristics and physician assessment were insufficient in the diagnosis or exclusion of spontaneous bacterial peritonitis in the ED patient undergoing diagnostic or therapeutic paracentesis. This finding supports routine laboratory fluid analysis after ED paracentesis.

Can clear ascitic fluid appearance rule out spontaneous bacterial peritonitis?

OBJECTIVE

The objective of the study was to determine the sensitivity and specificity of abnormal ascitic fluid appearance in the detection of spontaneous bacterial peritonitis (SBP), as a sensitivity approaching 100% could exclude SBP if the fluid is clear.

METHODS

We performed a retrospective review of all ascitic fluid samples sent for cell count over a 4-year period. Spontaneous bacterial peritonitis was defined as an absolute neutrophil count of more than 250 cells/mm3 or a positive culture. Abnormal fluid appearance was defined as hazy, cloudy, or bloody.

RESULTS

There were 916 ascitic fluid samples analyzed during the study period. Eighteen percent of samples had a clear appearance, whereas 82% were abnormal. Abnormal ascitic fluid appearance had a sensitivity of 98.1% (95% confidence interval, 95.3%-99.5%) and a specificity of 22.7% (95% confidence interval, 19.4%-26.3%) in the detection of SBP.

CONCLUSIONS

Abnormal fluid appearance has a high sensitivity for the detection of SBP. Thus, clear fluid might safely exclude SBP.

Predictors of success in nurse-performed ultrasound-guided cannulation

The objective of this study was to characterize factors affecting the success rate of nurse-performed ultrasound (US)-guided peripheral vein cannulation in difficult access patients. We prospectively enrolled patients who had two previous unsuccessful i.v. attempts. Nurses were trained in US-guided cannulation using a 7.5-MHz linear probe. The following characteristics were recorded: 1) reason for difficult access, 2) which upper arm veins could be sonographically visualized, 3) cannulation success, and 4) one- or two-person technique used. One hundred patients were enrolled. The cannulation success rate was 63%. Cannulation of the basilic vein was successful in 39 of 55 attempts (71%), whereas the success rate for the brachial vein was only 19 of 46 attempts (41%). The reason for difficult access and the one- or two-person technique did not affect success rate. The basilic vein was the best choice for cannulation, and the one-person technique was as successful as the two-person technique.

Continuous infusion of high-dose acyclovir for serious herpesvirus infections

Thirteen patients with herpesvirus infections who were unresponsive to at least 72 h of intermittent acyclovir administration received high-dose continuous infusion. Steady-state concentrations were maintained at between 20 and 98 mumol/liter. Of 12 patients who had continuous infusion for greater than 5 days, 7 (58%) resolved their infections, as determined by clinical and virologic parameters, suggesting that continuous infusion may succeed in some patients who do not respond to conventional therapy.

Human pharmacokinetics of the antiviral drug DHPG

The pharmacokinetics of the antiviral drug 9-[2-hydroxy-1-(hydroxymethyl) ethoxymethyl]guanine (DHPG) were examined in six patients receiving 2.5 or 5.0 mg/kg every 8 or 12 hours for human cytomegalovirus (HCMV) pneumonitis or retinitis. Biexponential decay with a mean distribution t1/2 of 0.23 hours and terminal t1/2 of 2.53 hours was observed. Total clearance correlated well with and exceeded creatinine clearance by a factor of 2.4. Mean volume of the central compartment was 15.26 L/1.73 m2 and the volume of distribution at steady state was 32.8 L/1.73 m2. Peak (model predicted) and trough plasma concentrations were 4.75 to 6.20 micrograms/ml and less than 0.25 to 0.63 microgram/ml, respectively, in patients receiving 2.5 mg/kg. Peak concentrations are well above those needed to inhibit HCMV at the 50% level (ID50) and troughs are near this ID50. Cerebrospinal fluid concentrations of DHPG indicate a penetration of 24% to 67%. No accumulation of DHPG was apparent in these patients. However, dosage reduction is necessary in renal insufficiency. Neutropenia occurred in one patient. The plasma concentration profile of DHPG suggests potential beneficial activity against HCMV.