Samuel Porter, MD

Background: While it is recognized that N95 respirator masks are better than regular medical masks at preventing the inhalation of aerosols, the question of whether they are better at preventing the transmission of infectious viral micro-organisms has never been studied in a robust randomized trial. Prior studies have shown mixed results, from noninferiority of medical masks to superiority of N95 masks, but these studies were stopped early or calibrated to detect outcomes of questionable clinical significance.

Study design: Cluster randomized, investigator-blinded pragmatic effectiveness study.

Setting: Seven outpatient health systems throughout the United States.

Synopsis: Data from 2,862 participants from 137 sites were gathered during the 12 weeks of peak influenza season during 2011-2015. Following analysis, there was no difference in objective laboratory evidence (by polymerase chain reaction or serum influenza seroconversion not attributable to vaccination) between the groups randomized to N95 masks and the groups randomized to regular medical masks. No significant difference in self-reported “flulike illness” or self-reported adherence to the intervention was noted between groups. Participants self-reported “never” adhering to the intervention about 10% of the time in both groups and adhering only “sometimes” about 25% of the time.

The study limitations included: most testing for infection occurred for self-reported symptoms with only a minor component of testing occurring at random; the self-reporting of secondary outcomes; and the somewhat high rate of nonadherence to either intervention. Although these are likely necessary trade-offs in a pragmatic trial.

Bottom line: N95 respirator masks are no better than regular medical masks are at preventing the transmission of influenza and other viral respiratory illnesses.

Citation: Radonovich LJ et al. N95 respirators vs. medical masks for preventing influenza among health care personnel: A randomized clinical trial. JAMA. 2019 Sep 3;322(9):824-33.

Dr. Porter is chief quality and safety resident at the Rocky Mountain Veterans Affairs Regional Medical Center, Aurora, Colo.

Background: While it is recognized that N95 respirator masks are better than regular medical masks at preventing the inhalation of aerosols, the question of whether they are better at preventing the transmission of infectious viral micro-organisms has never been studied in a robust randomized trial. Prior studies have shown mixed results, from noninferiority of medical masks to superiority of N95 masks, but these studies were stopped early or calibrated to detect outcomes of questionable clinical significance.

Study design: Cluster randomized, investigator-blinded pragmatic effectiveness study.

Setting: Seven outpatient health systems throughout the United States.

Synopsis: Data from 2,862 participants from 137 sites were gathered during the 12 weeks of peak influenza season during 2011-2015. Following analysis, there was no difference in objective laboratory evidence (by polymerase chain reaction or serum influenza seroconversion not attributable to vaccination) between the groups randomized to N95 masks and the groups randomized to regular medical masks. No significant difference in self-reported “flulike illness” or self-reported adherence to the intervention was noted between groups. Participants self-reported “never” adhering to the intervention about 10% of the time in both groups and adhering only “sometimes” about 25% of the time.

The study limitations included: most testing for infection occurred for self-reported symptoms with only a minor component of testing occurring at random; the self-reporting of secondary outcomes; and the somewhat high rate of nonadherence to either intervention. Although these are likely necessary trade-offs in a pragmatic trial.

Bottom line: N95 respirator masks are no better than regular medical masks are at preventing the transmission of influenza and other viral respiratory illnesses.

Citation: Radonovich LJ et al. N95 respirators vs. medical masks for preventing influenza among health care personnel: A randomized clinical trial. JAMA. 2019 Sep 3;322(9):824-33.

Dr. Porter is chief quality and safety resident at the Rocky Mountain Veterans Affairs Regional Medical Center, Aurora, Colo.

Background: While it is recognized that N95 respirator masks are better than regular medical masks at preventing the inhalation of aerosols, the question of whether they are better at preventing the transmission of infectious viral micro-organisms has never been studied in a robust randomized trial. Prior studies have shown mixed results, from noninferiority of medical masks to superiority of N95 masks, but these studies were stopped early or calibrated to detect outcomes of questionable clinical significance.

Study design: Cluster randomized, investigator-blinded pragmatic effectiveness study.

Setting: Seven outpatient health systems throughout the United States.

Synopsis: Data from 2,862 participants from 137 sites were gathered during the 12 weeks of peak influenza season during 2011-2015. Following analysis, there was no difference in objective laboratory evidence (by polymerase chain reaction or serum influenza seroconversion not attributable to vaccination) between the groups randomized to N95 masks and the groups randomized to regular medical masks. No significant difference in self-reported “flulike illness” or self-reported adherence to the intervention was noted between groups. Participants self-reported “never” adhering to the intervention about 10% of the time in both groups and adhering only “sometimes” about 25% of the time.

The study limitations included: most testing for infection occurred for self-reported symptoms with only a minor component of testing occurring at random; the self-reporting of secondary outcomes; and the somewhat high rate of nonadherence to either intervention. Although these are likely necessary trade-offs in a pragmatic trial.

Bottom line: N95 respirator masks are no better than regular medical masks are at preventing the transmission of influenza and other viral respiratory illnesses.

Citation: Radonovich LJ et al. N95 respirators vs. medical masks for preventing influenza among health care personnel: A randomized clinical trial. JAMA. 2019 Sep 3;322(9):824-33.

Dr. Porter is chief quality and safety resident at the Rocky Mountain Veterans Affairs Regional Medical Center, Aurora, Colo.

Background: Previous trials have shown a reduction in composite outcomes if STEMI patients undergo staged PCI of nonculprit lesions discovered incidentally at the time of primary PCI for STEMI. However, no randomized trial has had the power to assess if staged PCI of nonculprit lesions reduces cardiovascular death or MI.

Study design: Prospective randomized clinical trial.

Setting: PCI-capable centers in 31 countries.

Synopsis: In this study, if multivessel disease was identified during primary PCI for STEMI, patients were randomized to either culprit-lesion-only PCI or complete revascularization with staged PCI of all suitable nonculprit lesions (either during the index hospitalization or up to 45 days after randomization).

Overall, 4,041 patients from 140 centers were randomized with median 3-year follow-up. The complete revascularization group had lower rates of the primary composite outcome of death from cardiovascular disease or new MI (absolute reduction, 2.7%; 7.8% vs. 10.5%; number needed to treat, 37; hazard ratio, 0.74; 95% confidence interval, 0.60-0.91; P = .004). This finding was driven by lower incidence of new MI in the complete revascularization group – the incidence of death was similar between the groups. A coprimary composite outcome of death from cardiovascular causes, new MI, or ischemia-driven revascularization also favored complete revascularization, with an absolute risk reduction of 7.8% (8.9% vs. 16.7%; NNT, 13; HR, 0.51; 95% CI, 0.43-0.61; P less than .001). No statistically significant differences between groups were noted for the safety outcomes of major bleeding, stroke, stent thrombosis, or contrast-induced kidney injury.

Bottom line: Patients with STEMI who have multivessel disease incidentally discovered during primary PCI have a lower incidence of new MI and ischemia-driven revascularization when they undergo complete revascularization of all suitable lesions, as opposed to PCI of only their culprit lesion.

Citation: Mehta SR et al. Complete revascularization with multivessel PCI for myocardial infarction. N Engl J Med. 2019 Oct 10;381:1411-21.

Dr. Porter is chief quality and safety resident at the Rocky Mountain Veterans Affairs Regional Medical Center, Aurora, Colo.

Background: Previous trials have shown a reduction in composite outcomes if STEMI patients undergo staged PCI of nonculprit lesions discovered incidentally at the time of primary PCI for STEMI. However, no randomized trial has had the power to assess if staged PCI of nonculprit lesions reduces cardiovascular death or MI.

Study design: Prospective randomized clinical trial.

Setting: PCI-capable centers in 31 countries.

Synopsis: In this study, if multivessel disease was identified during primary PCI for STEMI, patients were randomized to either culprit-lesion-only PCI or complete revascularization with staged PCI of all suitable nonculprit lesions (either during the index hospitalization or up to 45 days after randomization).

Overall, 4,041 patients from 140 centers were randomized with median 3-year follow-up. The complete revascularization group had lower rates of the primary composite outcome of death from cardiovascular disease or new MI (absolute reduction, 2.7%; 7.8% vs. 10.5%; number needed to treat, 37; hazard ratio, 0.74; 95% confidence interval, 0.60-0.91; P = .004). This finding was driven by lower incidence of new MI in the complete revascularization group – the incidence of death was similar between the groups. A coprimary composite outcome of death from cardiovascular causes, new MI, or ischemia-driven revascularization also favored complete revascularization, with an absolute risk reduction of 7.8% (8.9% vs. 16.7%; NNT, 13; HR, 0.51; 95% CI, 0.43-0.61; P less than .001). No statistically significant differences between groups were noted for the safety outcomes of major bleeding, stroke, stent thrombosis, or contrast-induced kidney injury.

Bottom line: Patients with STEMI who have multivessel disease incidentally discovered during primary PCI have a lower incidence of new MI and ischemia-driven revascularization when they undergo complete revascularization of all suitable lesions, as opposed to PCI of only their culprit lesion.

Citation: Mehta SR et al. Complete revascularization with multivessel PCI for myocardial infarction. N Engl J Med. 2019 Oct 10;381:1411-21.

Dr. Porter is chief quality and safety resident at the Rocky Mountain Veterans Affairs Regional Medical Center, Aurora, Colo.

Background: Previous trials have shown a reduction in composite outcomes if STEMI patients undergo staged PCI of nonculprit lesions discovered incidentally at the time of primary PCI for STEMI. However, no randomized trial has had the power to assess if staged PCI of nonculprit lesions reduces cardiovascular death or MI.

Study design: Prospective randomized clinical trial.

Setting: PCI-capable centers in 31 countries.

Synopsis: In this study, if multivessel disease was identified during primary PCI for STEMI, patients were randomized to either culprit-lesion-only PCI or complete revascularization with staged PCI of all suitable nonculprit lesions (either during the index hospitalization or up to 45 days after randomization).

Overall, 4,041 patients from 140 centers were randomized with median 3-year follow-up. The complete revascularization group had lower rates of the primary composite outcome of death from cardiovascular disease or new MI (absolute reduction, 2.7%; 7.8% vs. 10.5%; number needed to treat, 37; hazard ratio, 0.74; 95% confidence interval, 0.60-0.91; P = .004). This finding was driven by lower incidence of new MI in the complete revascularization group – the incidence of death was similar between the groups. A coprimary composite outcome of death from cardiovascular causes, new MI, or ischemia-driven revascularization also favored complete revascularization, with an absolute risk reduction of 7.8% (8.9% vs. 16.7%; NNT, 13; HR, 0.51; 95% CI, 0.43-0.61; P less than .001). No statistically significant differences between groups were noted for the safety outcomes of major bleeding, stroke, stent thrombosis, or contrast-induced kidney injury.

Bottom line: Patients with STEMI who have multivessel disease incidentally discovered during primary PCI have a lower incidence of new MI and ischemia-driven revascularization when they undergo complete revascularization of all suitable lesions, as opposed to PCI of only their culprit lesion.

Citation: Mehta SR et al. Complete revascularization with multivessel PCI for myocardial infarction. N Engl J Med. 2019 Oct 10;381:1411-21.

Dr. Porter is chief quality and safety resident at the Rocky Mountain Veterans Affairs Regional Medical Center, Aurora, Colo.