Importance In December 2019, a novel coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) emerged in China and has spread globally, creating a pandemic. Information about the clinical characteristics of infected patients who require intensive care is limited.
Objective To characterize patients with coronavirus disease 2019 (COVID-19) requiring treatment in an intensive care unit (ICU) in the Lombardy region of Italy.
Design, Setting, and Participants Retrospective case series of 1591 consecutive patients with laboratory-confirmed COVID-19 referred for ICU admission to the coordinator center (Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy) of the COVID-19 Lombardy ICU Network and treated at one of the ICUs of the 72 hospitals in this network between February 20 and March 18, 2020. Date of final follow-up was March 25, 2020.
Exposures SARS-CoV-2 infection confirmed by real-time reverse transcriptase–polymerase chain reaction (RT-PCR) assay of nasal and pharyngeal swabs.
Main Outcomes and Measures Demographic and clinical data were collected, including data on clinical management, respiratory failure, and patient mortality. Data were recorded by the coordinator center on an electronic worksheet during telephone calls by the staff of the COVID-19 Lombardy ICU Network.
Results Of the 1591 patients included in the study, the median (IQR) age was 63 (56-70) years and 1304 (82%) were male. Of the 1043 patients with available data, 709 (68%) had at least 1 comorbidity and 509 (49%) had hypertension. Among 1300 patients with available respiratory support data, 1287 (99% [95% CI, 98%-99%]) needed respiratory support, including 1150 (88% [95% CI, 87%-90%]) who received mechanical ventilation and 137 (11% [95% CI, 9%-12%]) who received noninvasive ventilation. The median positive end-expiratory pressure (PEEP) was 14 (IQR, 12-16) cm H2O, and Fio2 was greater than 50% in 89% of patients. The median Pao2/Fio2 was 160 (IQR, 114-220). The median PEEP level was not different between younger patients (n = 503 aged ≤63 years) and older patients (n = 514 aged ≥64 years) (14 [IQR, 12-15] vs 14 [IQR, 12-16] cm H2O, respectively; median difference, 0 [95% CI, 0-0]; P = .94). Median Fio2 was lower in younger patients: 60% (IQR, 50%-80%) vs 70% (IQR, 50%-80%) (median difference, −10% [95% CI, −14% to 6%]; P = .006), and median Pao2/Fio2 was higher in younger patients: 163.5 (IQR, 120-230) vs 156 (IQR, 110-205) (median difference, 7 [95% CI, −8 to 22]; P = .02). Patients with hypertension (n = 509) were older than those without hypertension (n = 526) (median [IQR] age, 66 years [60-72] vs 62 years [54-68]; P < .001) and had lower Pao2/Fio2 (median [IQR], 146 [105-214] vs 173 [120-222]; median difference, −27 [95% CI, −42 to −12]; P = .005). Among the 1581 patients with ICU disposition data available as of March 25, 2020, 920 patients (58% [95% CI, 56%-61%]) were still in the ICU, 256 (16% [95% CI, 14%-18%]) were discharged from the ICU, and 405 (26% [95% CI, 23%-28%]) had died in the ICU. Older patients (n = 786; age ≥64 years) had higher mortality than younger patients (n = 795; age ≤63 years) (36% vs 15%; difference, 21% [95% CI, 17%-26%]; P < .001).
Conclusions and Relevance In this case series of critically ill patients with laboratory-confirmed COVID-19 admitted to ICUs in Lombardy, Italy, the majority were older men, a large proportion required mechanical ventilation and high levels of PEEP, and ICU mortality was 26%.
In this case series of critically ill patients admitted to ICUs in Lombardy, Italy, with laboratory-confirmed COVID-19 from February 20 to March 18, 2020, the majority were older men, a large proportion required mechanical ventilation and high levels of PEEP, and ICU mortality was 26%.
The majority of patients in this case series were admitted to the ICU because of acute hypoxemic respiratory failure that required respiratory support. Endotracheal intubation and invasive mechanical ventilation were needed in 88% of the patients, whereas only 11% could be managed with noninvasive ventilation. The need for invasive mechanical ventilation in this patient population was higher than that recently reported for other ICU patients: 71% (Washington State, US),47% (Wuhan, China), 42% (Wuhan, China)10 and 30% (Wuhan, China; of note, half of these were treated with ECMO).The need for invasive mechanical ventilation in this critically ill Italian patient population was also higher compared with data reported by 2 Chinese studies from Wuhan, including all adult inpatients with laboratory-confirmed COVID-19 and patients hospitalized with severe disease (with rates of 17%and 15% respectively).
Conversely, in previously cited reports, noninvasive ventilation has been used much more frequently both inside and outside the ICU. For the ICU population, the use of noninvasive ventilation was reported as 19% (Washington State, US),42% (Wuhan, China),56% (Wuhan, China),and 62% (Wuhan, China; of note, this value included patients receiving high-flow nasal cannula).In previous reports, noninvasive ventilation was used in 14% of adult inpatients with laboratory-confirmed COVID-19 and 32% of hospitalized patients with severe laboratory-confirmed COVID-19.
The higher rate of intubation in the current case series could be due to the severity of hypoxia (the median Pao2/Fio2 was 160), thus requiring high levels of PEEP. However, in one of the recent reports, the Pao2/Fio2 ratio upon ICU admission was even lower (136).Another potential explanation is that the majority of the patients requiring noninvasive ventilation in northern Italy were able to be managed outside the ICU and were thus not included in this report. Data regarding use of respiratory support were missing for some patients (n = 291, or 18.3%), which may also have influenced the rates of respiratory support reported in this study.
The population in this study consisted mostly of men (82%, which is higher than previously reported) and older individuals.The median age of the patients admitted to the ICU was 63 (IQR, 56-70) years old, which is the same as the median age of all the positive Italian cases with COVID-19 suggesting that, to date, older age alone is not a risk factor for admission to the ICU.
In this cohort of patients, 68% had at least 1 comorbidity, in line with that reported by Wang et al (72.2%), but much higher than in other reports.Similar to other previous reports,hypertension was the most common comorbidity, followed by cardiovascular disorders, hypercholesterolemia, and diabetes. Among older patients, comorbidities were common but a relatively small percentage of patients had pulmonary disease.
Previous reports described different mortality rates among patients requiring ICU admission, from 16%9 to 38%,62%,67%, and 78%.In this study, at 5 weeks after the first admission in ICU, the majority of the patients (58%) were still in the ICU, 16% of the patients had been discharged from the ICU, and 26% had died in the ICU. The death rate was higher among those who were older. However, these outcome data should be interpreted with caution because most patients were still hospitalized in the ICU and the minimum follow-up was 7 days; in particular, the mortality rate could eventually be higher.
To the best of our knowledge, this is the largest case series of patients with COVID-19 and severe illness who required admission to the ICU. Available data indicate considerable variability among different countries in both the proportion of severe cases of COVID-19 among those testing positive and in the proportion of severe cases of COVID-19 among those hospitalized with the disease. Among western countries, Italy seems to have a higher rate of severely ill patients and thus it is particularly relevant to report the demographic and clinical characteristics of this population upon admission to the ICU. The majority of the patients had moderate to severe respiratory failure and required invasive mechanical ventilation and high levels of PEEP.
These data could reflect a different organization of health care systems in the world. In Italy, for instance, noninvasive ventilation is delivered both in ICUs and in other hospital wards. The amount of intensive care support that has been provided by intensivists outside of previously existing ICUs and newly created ICUs was not quantified. While the final figures are not yet available, the number of level 2 ICU beds (providing high-flow oxygen, continuous positive airway pressure, or noninvasive ventilation) is estimated to be high with a large number of beds created to increase capacity to deal with severely ill patients during the COVID-19 outbreak. These data will be collected soon to provide a complete description of the critically ill patients with COVID-19.
These data also suggest that the need for organ support and intensive care, regardless of the reason, in the COVID-19 outbreak is substantial, with 9% of all positive cases being probably a conservative estimate. The volume of critically ill patients with COVID-19 infection that ICUs might be required to manage may be substantial, and adequate ICU capacity to deal with severe respiratory failure should be planned.
This study has several limitations. First, this was a retrospective study, and data were acquired via telephone. Second, the critical nature of the Lombardy situation did not allow the coordinator to obtain more detailed information, such as baseline medication use. Third, the follow-up time is still relatively short compared with the course of the disease, and the reported mortality data and length of stay data reported in this study could change. Fourth, there were relatively large amounts of missing data for some outcomes.
In this case series of critically ill patients with laboratory-confirmed COVID-19 admitted to ICUs in Lombardy, Italy, the majority were older men, a large proportion required mechanical ventilation and high levels of PEEP, and ICU mortality was 26%.
Reference & Source information: https://jamanetwork.com/
Read More on: