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Predictors of early hospital readmission in patients receiving home mechanical ventilation

Open AccessPublished:October 17, 2022DOI:https://doi.org/10.1016/j.hrtlng.2022.10.004

      Highlights

      • Pneumonia is the most common reason of an unplanned hospital readmission within a year in patients receiving home mechanical ventilation (HMV).
      • Higher rates of early readmission found with invasive HMV than with non-invasive HMV.
      • Nasogastric tube feeding, sequelae of pneumonia or acute respiratory distress syndrome, and central nervous system disorders as causes for HMV were significantly associated with early readmission.

      Abstract

      Background

      Although the proportion of patients with chronic respiratory failure requiring home mechanical ventilation (HMV) is increasing, hospital readmissions in these patients are also increasing.

      Objective

      We investigated the factors for early readmission in patients receiving HMV.

      Methods

      We retrospectively analyzed the data of adult patients readmitted to the hospital within a year who first received HMV and were discharged from the Asan Medical Center between March 2014 and February 2019. We compared the clinical characteristics at discharge before readmission between the early (readmission within 30 days) and late readmission groups (readmission between day 31 and 1 year) and investigated the clinical characteristics and outcomes at readmission.

      Results

      Of the 116 patients identified, 36.2% had been readmitted early. The patients who received invasive HMV had a higher rate of early readmission than those who received non-invasive HMV. Pneumonia was the most common reason of readmission in the two groups. The rate of aspiration was significantly higher in the early readmission group (28.6% vs. 8.1%; P = .003). In multivariate logistic regression analysis, nasogastric tube feeding, sequelae of pneumonia or acute respiratory distress syndrome, and central nervous system disorders as causes for HMV were significantly associated with early readmission.

      Conclusion

      Feeding methods and causes for HMV were associated with early readmission. Educating caregivers on respiratory care (suction and feeding methods) is important for preventing early readmission.

      Keywords

      Introduction

      Recent technical developments in respiratory therapy have resulted in an increase in home mechanical ventilation (HMV) use in patients with chronic respiratory failure discharged to their homes or long-term care hospitals.
      • Povitz M
      • Rose L
      • Shariff SZ
      • et al.
      Home mechanical ventilation: a 12-year population-based retrospective cohort study.
      HMV enables patients who require long-term mechanical ventilation to be discharged from the intensive care unit (ICU) and continue the treatment in their home environments; thus, HMV has led to positive outcomes such as an improved quality of life, reduction in hospital costs, lower risk of hospital infections, and an increased survival rate.
      • Sevick MA
      • Kamlet MS
      • Hoffman LA
      • Rawson I.
      Economic cost of home-based care for ventilator-assisted individuals: a preliminary report.
      However, it is noteworthy that unplanned readmissions among patients receiving HMV increase hospital costs and higher psychological burden on the whole health care team.
      • Bertrand P
      • Fehlmann E
      • Lizama M
      • Holmgren N
      • Silva M
      • Sánchez I.
      Home ventilatory assistance in Chilean children: 12 years' experience. Article in Spanish.
      • Ottonello G
      • Ferrari I
      • Pirroddi IM
      • et al.
      Home mechanical ventilation in children: retrospective survey of a pediatric population.
      • Srinivasan S
      • Doty SM
      • White TR
      • et al.
      Frequency, causes, and outcome of home ventilator failure.
      The average readmission time for long-term ventilator patients was 39.2 days, and pneumonia was the main cause of readmission.
      • Douglas SL
      • Daly BJ
      • Brennan PF
      • Gordon NH
      • Uthis P.
      Hospital readmission among long-term ventilator patients.
      ,
      • Ahn JJ
      • Lee KM
      • Shim TS
      • et al.
      Survey of current status of the patients with home ventilator in Seoul and Kyunggi province.
      The incidence of pneumonia in patients receiving HMV is 59.6%, which is higher than that reported in acute care hospitals.
      • Hwang MS
      • Chang SJ.
      Self-care education experience, self-care performance, and home care service needs of patients with rare and incurable diseases who use a home ventilator.
      According to the American Association for Respiratory Care practice guidelines, readmissions or deaths associated with HMV typically occur due to aggravation of the underlying disease, respiratory infections, side effects related to airways, and ventilation failure.
      American Association for Respiratory Care, Respiratory Home Care Focus Group
      AARC clinical practice guideline. Long-term invasive mechanical ventilation in the home: 2007 revision & update.
      In a previous study on children, unplanned readmissions occurred within a short period of approximately 1–3 months after starting HMV in 40–70% of the discharged patients. In addition, the causes of these unplanned readmissions were principally pneumonia and airway-related problems, which are preventable.
      • Kun SS
      • Edwards JD
      • Ward SL
      • Keens TG.
      Hospital readmissions for newly discharged pediatric home mechanical ventilation patients.
      ,
      • Kim MH
      • Kim HS
      • Park JD.
      Factors influencing readmission of home ventilator-assisted children.
      Unplanned hospital readmissions have been reported in various disease groups and have a significant cost burden.
      • Ashton CM
      • Wray NP
      • Dunn JK
      • Scheurich JW
      • DeBehnke RD
      • Friedland JA.
      Predicting readmission in veterans with chronic disease. Development and validation of discharge criteria.
      A shortfall in medical care prior to discharge is commonly regarded as the cause of early readmission (i.e., within 30 days); therefore, many medical institutions are making efforts to reduce this incidence. Therefore, studies on the clinical characteristics, causes, and possible prevention strategies related to the unplanned early readmission in these patients are required. Hence, we analyzed the clinical characteristics and causes of readmission in adult patients starting HMV and evaluated possible mitigation approaches.

      Methods

      Study design and patient population

      We retrospectively evaluated data of patients (>18 years old) who first received HMV and were discharged from the Asan Medical Center between March 2014 and February 2019, and were readmitted to the hospital within a year. We included those cases who were in-patients or who were discharged or transferred after initial resuscitation in the emergency room. For patients who experienced more than one readmission, we included only the first readmission. We excluded patients transferred to other hospitals, had discontinued treatment, or had died. Also, we excluded the patients who were readmitted for a planned procedure or rehabilitation. Patients who were readmitted within 30 days were assigned to the early readmission group and those readmitted within a year from the 31st day were assigned to the late readmission group (Fig. 1).
      This study was approved by the Ethics Committee of the Asan Medical Center (No. 2020-1036). The requirement for informed consent was waived because of the retrospective nature of the analysis.

      Data collection

      In the present study, HMV was defined as the daily use of non-invasive or invasive ventilation at home or in a long-term care facility. We excluded patients with only obstructive sleep apnea and used continuous positive airway pressure ventilation.
      We used the Deyo–Charlson score to standardize the value of any underlying disease. This score was calculated by summing the scores of the differential effects of 17 different chronic diseases on mortality.
      • Charlson ME
      • Pompei P
      • Ales KL
      • MacKenzie CR.
      A new method of classifying prognostic comorbidity in longitudinal studies: development and validation.
      A Deyo–Charlson score of ≥3 was considered significant in terms of the readmission risk.
      • Halfon P
      • Eggli Y
      • van Melle G
      • Chevalier J
      • Wasserfallen JB
      • Burnand B
      Measuring potentially avoidable hospital readmissions.
      ICU management was defined as management involving the use of a conventional ventilator for more than 96 h through an artificial airway in the ICU. Problems with devices were defined as cases of readmission for replacement due to dysfunction of the devices maintained for treatment, such as tracheostomy tubes, feeding tubes, HMV devices, and other drainage tubes.
      Patient data were collected from electronic medical records. We investigated the clinical characteristics of patients, cause for HMV application, and equipment (HMV) characteristics at the time of discharge. Factors related to early readmission were analyzed by comparing the clinical characteristics, cause for HMV application, and equipment (HMV) characteristics before discharge, between the early and late readmission groups. In addition, we investigated the clinical characteristics and outcomes of patients at the time of readmission.
      At discharge, the following clinical characteristics were analyzed: age, sex, comorbidities (solid cancer, hematologic malignancy, chronic renal disease on hemodialysis, chronic liver disease), Deyo-Charlson score, intensive care treatments, functional status (bedridden), unresponsive mental status, feeding methods (oral, gastrostomy tube, and nasogastric tube), length of hospital stay, the type of HMV used (i.e., non-invasive ventilation [NIV] or invasive ventilation [IV]), and place of residence after discharge (i.e., home or long-term care hospital).
      We investigated the cause for HMV application (i.e., progression of chronic lung disease, neuromuscular disease, sequelae of pneumonia or acute respiratory distress syndrome, central nervous system disorder, congestive heart failure, and others).
      To better understand the equipment (HMV) characteristics at the time of discharge, the inspiratory pressure, oxygen supply, support schedule (i.e., night time, night time and as-needed, all day, and as-needed), and length of mechanical ventilation were evaluated.
      To determine the clinical characteristics and outcomes at the time of unplanned readmission, we investigated the period from discharge to readmission, the causes of readmission (i.e., an acute exacerbation of the initial cause for HMV, occurrence of the new problems, problems with devices), the route of readmission (ER), hospital unit for treatment (ER, ICU, or GW), and survival to discharge.

      Statistical analysis

      All the data were expressed as median and interquartile range or number of patients (n; %). Normally distributed variables were compared using the chi-square or Fisher's exact test, and the mean values of the two readmission groups were compared using the Student's t-test. Non-normally distributed, continuous variables were compared using the Mann–Whitney U test. To identify preventable factors of early readmission, independent variables that showed a significant difference in univariate analysis were included in multivariate logistic regression. Variables included in univariate analysis were clinical characteristics of patient and equipment (HMV) characteristics. Variables with a P value of ≤.10 in univariate analysis were included in the multivariable logistic regression analysis. The variables for the multivariate analysis were calculated using bootstrapping, a nonparametric method that takes 1000 samples of the data. Backward elimination was performed using the likelihood ratio method. Model adequacy was assessed using the Hosmer–Lemeshow goodness-of-fit test. Data are presented as odds ratios with 95% confidence intervals. A 2-sided P value of <.05 was considered significant.
      Statistical analyses were conducted using SPSS version 21.0 for Windows (SPSS, Chicago, IL, USA).

      Results

      One hundred sixteen patients with unplanned readmission within a year from discharge were enrolled. Clinical characteristics at discharge before readmission were described in Table 1. Forty-two (36.2%) patients were assigned to the early readmission group and 74 (64.8%) to the late readmission group. The mean age was 68.5 years and 60.3% of the patients were male. Solid cancers as comorbidities were significantly higher in the early readmission group (19.0% vs. 5.4%; P = .020). Sixty-four (55.2%) patients had a Deyo–Charlson score of ≥3. The Deyo–Charlson scores (≥3 points) were not different between the early and late readmission groups (64.3% vs. 50.0%; P = .137). ICU management (66.7% vs. 37.8%; P = .003) and an unresponsive mental status (16.7% vs. 5.4%; P = .047) were significantly higher in the early readmission group. However, oral feeding (40.5% vs. 68.9%; P = .003) and home discharge (50.0% vs. 74.3%; P = .008) were significantly higher in the late readmission group. Regarding the type of HMV, IV was more common than NIV in the early readmission group (61.9% vs. 27.0%; P < .001).
      Table 1Clinical characteristics of patients at the time of discharge.
      VariablesTotal (n = 116)Late readmission group (n = 74)Early readmission group (n = 42)P value
      Age, years68.5(57–75)65(56–74)70(61–77.3).622
      Sex, male70(60.3)46(62.2)24(57.1)0.595
      Comorbidities
       Solid cancer12(10.3)4(5.4)8(19.0)0.020
       Hematologic malignancy11(9.5)7(9.5)4(9.5)0.991
       Chronic renal disease on HD7(6.0)4(5.4)3(7.1)0.703
       Chronic liver disease4(3.4)2(2.7)2(4.8)0.620
      Deyo–Charlson score (≥3)64(55.2)37(50.0)27(64.3)0.137
      ICU management56(48.3)28(37.8)28(66.7)0.003
      Bed ridden status51(44.0)29(39.2)22(52.4)0.169
      Unresponsive mental status11(9.5)4(5.4)7(16.7)0.047
      Feeding method
       Oral68(58.6)51(68.9)17(40.5)0.003
       Gastrostomy tube32(27.6)18(24.3)14(33.3)0.297
       Nasogastric tube16(13.8)5(6.8)11(26.2)0.004
      Length of hospital stay, days18.5(11–51.5)15.5(10–35)29(13.8–66)0.008
      Place of residence after discharge0.008
       Home76(65.5)55(74.3)21(50.0)
       Long-term care hospital40(34.5)19(25.7)21(50.0)
      Type of HMV<0.001
       Non-invasive ventilation70(60.3)54(73.0)16(38.1)
       Invasive ventilation46(39.7)20(27.0)26(61.9)
      Note: Data are presented as median and interquartile range or frequency (%). P value was between the early readmission group and late readmission group.
      Abbreviations: HD, hemodialysis; ICU, intensive care unit; HMV, home mechanical ventilation.
      A comparison of the reasons for HMV application in the early and late readmission groups is presented in Table 2. The progression of chronic lung disease was significantly higher in the late readmission group (31.0% vs. 51.4%; P = .033), whereas the sequelae of pneumonia or ARDS (26.2% vs. 8.1%; P = .008) and central nervous system disorders (21.4% vs. 5.4%; P = .009) were significantly higher in the early readmission group.
      Table 2Cause for HMV application in the early and late readmission groups at the time of discharge.
      VariablesTotal (n = 116)Late readmission group (n = 74)Early readmission group (n = 42)P value
      Progression of chronic lung disease51(44.0)38(51.4)13(31.0)0.033
       COPD19(16.4)14(18.9)5(11.9)
       Tuberculosis destroyed lung8(6.9)7(9.5)1(2.4)
       Bronchiectasis7(6.0)6(8.1)1(2.4)
       Bronchiolitis obliterans7(6.0)5(6.8)2(4.8)
       Interstitial lung disease7(6.0)5(6.8)2(4.8)
       Advanced lung cancer2(1.7)1(1.4)1(2.4)
       Asthma1(0.9)0(0.0)1(2.4)
      Neuro muscular disease21(18.1)15(20.3)6(14.3)0.421
       Amyotrophic lateral sclerosis19(16.4)13(17.6)6(14.3)
       Neuromuscular junction disease2(1.7)2(2.7)0(0.0)
      Sequelae of pneumonia or ARDS17(14.7)6(8.1)11(26.2)0.008
      Central nervous system disorder13(11.2)4(5.4)9(21.4)0.009
       Brain tumor5(4.3)2(2.7)3(7.1)
       Stroke4(3.4)2(2.7)2(4.8)
       Neurodegenerative disorder3(2.6)0(0.0)3(7.1)
       Hypoxic brain injury1(0.9)0(0.0)1(2.4)
      Congestive heart failure8(6.9)6(8.1)2(4.8)0.494
      Others6(5.2)5(6.8)1(2.4)0.415
       Restrictive thoracic cage disorder5(4.3)4(5.4)1(2.4)
       Obesity hypoventilation syndrome1(0.9)1(1.4)0(0.0)
      Note: Data are presented as frequency (%). P value was between the early readmission group and late readmission group.
      Abbreviations: HMV, home mechanical ventilation; COPD, chronic obstructive pulmonary disease; ARDS, acute respiratory distress syndrome.
      HMV equipment characteristics in the early and late readmission groups at the time of discharge are presented in Table 3. Regarding the HMV support time, all-day support was significantly more frequent in the early readmission group (47.6% vs. 21.6%; P = .004). The length of mechanical ventilation in the early readmission group was significantly longer than in the late readmission group (26.5 days vs. 14 days; P = .005).
      Table 3HMV equipment characteristics in the early and late readmission groups at the time of discharge.
      VariablesTotal (n = 116)Late readmission group (n = 74)Early readmission group (n = 42)P value
      Inspiratory pressure, cm H2O14(12–16)16(14–18)15(12–18)0.297
      Need for oxygen84(72.4)54(73.0)30(71.4)0.858
      Support schedule
       Night-time42(36.2)30(40.5)12(28.6)0.157
       Night-time and as-needed36(31.0)27(36.5)9(21.4)0.092
       All day36(31.0)16(21.6)20(47.6)0.004
       As-needed2(1.7)1(1.4)1(2.4)1.000
      Length of MV, days17.5(10.3–40)14(9–29)26.5(13–50)0.005
      Length of MV (>30 days)35(30.2)17(23.0)18(42.9)0.025
      Note: Data are presented as median and interquartile range or frequency (%). P value was between the early readmission group and late readmission group.
      Abbreviations: HMV, home mechanical ventilation; MV, mechanical ventilation.
      The clinical characteristics and outcomes at the time of the unplanned readmission are presented in Table 4. For the 116 patients, the mean time from discharge to readmission was 53.5 [19–123] days; for the early readmission group, it was 11 [6.8–22.3] days and for the late readmission group, it was 92 [54–174.5] days (P < .001). The route of admission commenced at the emergency room in 90.5% of the patients. Hospital units where patients received treatment at readmission were the general ward (62.1%), emergency room (21.5%), and ICU (16.4%). Pneumonia was the most common reason of readmission in the study population (36.2%). There was no significant difference in the occurrence of pneumonia between the early and late readmission groups (26.2% vs. 41.9%; P = .091). However, aspiration (28.6% vs. 8.1%; P = .003) and acute exacerbation of sequelae of pneumonia or ARDS (11.9% vs. 1.4%; P = .023) were significantly higher in the early readmission group. Survival to discharge was 81.0% in the early readmission group and 91.9% in the late readmission group; the difference was not statistically significant.
      Table 4Clinical characteristics and outcomes at the time of readmission.
      VariablesTotal (n = 116)Late readmission group (n = 74)Early readmission group (n = 42)P value
      Time from discharge to readmission, days53.5(19–123)92(54–174.5)11(6.8–22.3)< 0.001
      Cause of readmission
      AE of the initial cause for HMV26(22.5)17(23.0)9(21.4)
       Chronic lung disease11(9.5)8(10.8)3(7.1)0.517
       Neuromuscular disease3(2.6)2(2.7)1(2.4).000
       Sequelae of pneumonia or ARDS6(5.2)1(1.4)5(11.9)0.023
       Central nervous system disorders1(0.9)1(1.4)0(0.0)1.000
       Congestive heart failure2(1.7)2(2.7)0(0)0.534
       Others3(2.6)3(4.0)0(0.0)0.552
      Occurrence of the new problem71(61.2)45(60.8)26(61.9)
       Pneumonia42(36.2)31(41.9)11(26.2)0.091
       Aspiration18(15.5)6(8.1)12(28.6)0.003
       Others11(9.5)8(10.8)3(7.1)0.517
      Devices problem19(16.3)12(16.2)7(16.7)
       Tracheostomy tube4(3.4)1(1.4)3(7.1)0.134
       Feeding tube10(8.6)10(13.5)0(0.0).013
       HMV devices3(2.6)1(1.4)2(4.8)0.297
       Drainage tube2(1.7)0(0.0)2(4.8)0.129
      Route of admission, ER105(90.5)67(90.5)38(90.5)1.000
      Hospital unit for treatment0.470
       GW72(62.1)49(66.2)23(54.8)
       ER25(21.5)14(18.9)11(26.2)
       ICU19(16.4)11(14.9)8(19.0)
      Survival to discharge102(87.9)68(91.9)34(81.0)0.082
      Note: Data are presented as median and interquartile range or frequency (%). P value was between the early readmission group and late readmission group.
      Abbreviations: AE, acute exacerbation; HMV, home mechanical ventilation; ARDS, acute respiratory distress syndrome; ER, emergency room; GW, general ward; ICU, intensive care unit.
      Using a multivariate logistic regression model, three variables were independently associated with unplanned early readmission: using a nasogastric tube, experiencing the sequelae of pneumonia or ARDS, and central nervous system disorders (Table 5).
      Table 5Prognostic factors for early readmission identified by univariate and multivariate logistic regression analyses.
      VariablesUnivariate logistic regression analysisMultivariate logistic regression analysis
      Odds ratio (95% CI)POdds ratio (95% CI)P
      Comorbidities, solid cancer2.59(0.26–12.05)0.03
      ICU management1.88(0.58–6.14)<0.01
      Unresponsive mental state1.38(0.21–9.21)0.06
      Feeding method, nasogastric tube2.62(0.59–11.54)<0.013.74(1.11–12.62)0.03
      Discharge to long-term care hospital1.10(0.36–3.34)<0.01
      Cause for HMV application
       CLD1.85(0.56–6.14)0.04
       Sequelae of pneumonia or ARDS5.22(1.23–22.23)0.014.81(1.55–14.96)<0.01
       CNS disorder3.99(0.59–26.92)0.015.48(1.48–20.36)0.01
      Type of HMV, invasive ventilation2.04(0.30–13.93)<0.01
      Support schedule, all day0.83(0.14–5.05)<0.01
      Length of MV (>30 days)0.58(0.17–1.99)0.03
      Abbreviations: CI, confidence interval; ICU, intensive care unit; HMV, home mechanical ventilation; CLD, chronic lung disease; ARDS, acute respiratory distress syndrome; CNS, central nervous system; MV, mechanical ventilation.
      The main study group (116 patients) was divided into an NIV group (70 patients) and IV group (46 patients) and analyzed by comparing clinical characteristics at the time of discharge and readmission. The results are presented in Supplemental Table 1. On comparing the NIV and IV groups, the rates of solid cancer (4.3% vs. 19.6%; P = .008), bed ridden status (18.6% vs. 82.6%; P < .001), length of hospital stay (12.5 days vs. 51 days; P < .001), and sequelae of pneumonia or ARDS (5.7% vs. 28.3%; P = .001) due to HMV application were significantly higher in the IV group. The rates of oral feeding (92.9 vs. 6.5%; P < .001) and progression of chronic lung disease due to HMV application (67.1% vs. 8.7%; P < .001) were significantly higher in the NIV group. The mean time from discharge to readmission was 59 [34.3–152] days in the NIV group and 23 [8.8–78.5] days in the IV group (P = .002). The rate of readmission due to pneumonia was significantly higher in the NIV group (52.9% vs. 10.9%; P < .001).
      Next, the IV group (46 patients) were divided into an early readmission group (26 patients) and a late readmission group (20 patients), and their clinical characteristics and outcomes at discharge and readmission were compared. The results are presented in Supplemental Table 2. On comparing early and late readmission groups, the rate of readmission due to acute exacerbation of the sequelae of pneumonia or ARDS was significantly higher in the early readmission group (19.2% vs. 0%; P = .038), whereas problems with devices (feeding tube) were significantly higher in the late readmission group (0% vs. 45%; P < .001). The rate of aspiration was higher in the early readmission group but not significantly (38.5% vs. 20%; P = .177). Survival to discharge after readmission was significantly lower in the early readmission group (80.8% vs. 100%; P = .038).

      Discussion

      Fragile patients starting HMV at discharge are at risk of unplanned readmission because of several factors such as chronic respiratory failure, issues with the application of complex medical devices, and insufficient support for home care. In this present study, we evaluated clinical characteristics and risk factors of readmission. The patients who received invasive HMV had a higher rate of early readmission than those who received non-invasive HMV. When performing subgroup analysis of patients who received invasive HMV, acute exacerbations of sequelae of pneumonia or ARDS was associated with early readmission. Pneumonia was the most common reason of readmission in a year. The rate of aspiration was significantly higher in the early readmission group. In this multivariate analysis, nasogastric tube feeding and sequelae of pneumonia or ARDS and CNS disorder as a cause for HMV were independently associated with early readmission after the commencement of HMV.
      According to Aston et al., the 1-month readmission rate of patients with chronic disease was approximately 5–10%.
      • Ashton CM
      • Wray NP
      • Dunn JK
      • Scheurich JW
      • DeBehnke RD
      • Friedland JA.
      Predicting readmission in veterans with chronic disease. Development and validation of discharge criteria.
      Another study reported that 21.1% of the patients who were on the ventilator in the ICU for more than 96 hours were readmitted within 30 days after discharge.
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      Hospital readmission among long-term ventilator patients.
      In addition, a study found that 40.6% of the patients who had been admitted to the ICU for more than 1 week were readmitted within a year and 22.9% were readmitted within 30 days.
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      Compared to previous studies, in this present study, 64.8% of the patients were readmitted within a year, with 36.2% of them being readmitted within 30 days, showing a high unplanned readmission rate. This difference may be due to the inclusion of only HMV-applied patients in this study. In this present study, 66.7% of the early readmission group patients had received ICU management, and 41.4% needed tube feeding (i.e., gastrostomy tube or nasogastric tube). In addition, sequelae of pneumonia or ARDS and CNS disorders as causes for HMV application, mechanical ventilation via tracheostomy tube, and prolonged mechanical ventilation were high in the early readmission group.
      Ventilator associated pneumonia (VAP) is caused by contamination in the airways due to long-term application of a ventilator, invasion of microorganisms through a tracheostomy tube, and insufficient adherence to aseptic technique during endotracheal suction.
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      • Gatell JM
      • et al.
      Incidence, risk, and prognosis factors of nosocomial pneumonia in mechanically ventilated patients.
      In this present study, compared to the use of oral and gastrostomy feeding tubes, the nasogastric feeding tube was significantly more common in the early readmission group, suggesting that nasogastric tube feeding may increase the incidence of aspiration. Therefore, proper education for suctioning, including preventing contamination of the suction catheter and increasing the frequency of oral suction to prevent aspiration into the lungs, should be provided to caregivers prior to discharge. In addition, education on feeding methods such as the appropriate head elevation and proper feeding speed control is advisable.
      • McKim DA
      • Road J
      • Avendano M
      • et al.
      Home mechanical ventilation: a Canadian thoracic society clinical practice guideline.
      The sequelae of pneumonia or ARDS and central nervous system disorders as cause for HMV application, and nasogastric tube feeding were the factors influencing early readmission. In addition, subgroup analysis of patients on invasive HMV showed that the patients who were received HMV due to the sequelae of pneumonia or ARDS were readmitted early because their symptoms worsened again after discharge. Considering the characteristics of this disease, most of these patients require a conventional ventilator in the ICU and change to a home ventilator because of difficult weaning. The recent development of respiratory therapy has encouraged patients who are critically ill to survive and be discharged from the ICU. However, these patients may subsequently develop post-intensive care syndromes such as critical illness polyneuromyopathy, cachexia, weakness, organ dysfunction, and cognitive impairment and these problems lead to prolonged HMV. Therefore, a multidisciplinary approach such as rehabilitation and disease status monitoring is required to improve patient outcomes.
      • Mehlhorn J
      • Freytag A
      • Schmidt K
      • et al.
      Rehabilitation interventions for postintensive care syndrome: a systematic review.
      In hypercapnic respiratory failure, lowering the level of partial pressure of carbon dioxide is the key goal of HMV when it is first employed; hence, most patients apply non-invasive mechanical ventilation during sleep. It has been reported that the use of non-invasive ventilation at night reduces the rate of readmission by lowering the risk of acute exacerbation of chronic lung disease and improves the quality of life of patients.
      • Douglas SL
      • Daly BJ
      • Brennan PF
      • Gordon NH
      • Uthis P.
      Hospital readmission among long-term ventilator patients.
      ,
      • Ankjærgaard KL
      • Maibom SL
      • Wilcke JT.
      Long-term non-invasive ventilation reduces readmissions in COPD patients with two or more episodes of acute hypercapnic respiratory failure.
      A previous study reported that 20.4% of patients with chronic obstructive pulmonary disease had to be readmitted within 30 days.
      • Camberg LC
      • Smith NE
      • Beaudet M
      • Daley J
      • Cagan M
      • Thibault G.
      Discharge destination and repeat hospitalizations.
      In this present study, the rate of applying a home ventilator for chronic lung disease was 44%. However, among them, 10.8% were readmitted within a year and 7.1% were readmitted within 30 days because of acute exacerbation. These results suggest that HMV helps reduce the frequency of acute exacerbations in patients with chronic lung disease.
      Srinivasan et al.
      • Srinivasan S
      • Doty SM
      • White TR
      • et al.
      Frequency, causes, and outcome of home ventilator failure.
      reported that 39% of the patients who were visited at home by the vendor for ventilator dysfunction had operational problems; however, most issues were resolved at home without any side effects. Only two patients required hospitalization because of care-related patient factors not due to a defect in the equipment. In this present study, 16.3% of the patients were readmitted within a year due to problems with the devices, and only 2.6% of them had ventilator problems. This means that it is more likely to be a functional problem of an artificial airway or feeding tube or drainage tube for disease treatment than a mechanical problem. Problem with home mechanical ventilator equipment may not be a major issue for readmission.
      This study has some limitations. The current investigation was a single institutional study, limiting the general applicability of the data. In addition, we may have underestimated the readmission rates because 32% of patients did not revisit this hospital and we could not evaluate whether they did unplanned readmission at another institution. We did not evaluate the quality of home care or long-term care hospitals in-depth. Care liaison services must be in place to evaluate the reasons of readmission. Given the medical state of patients undergoing HMV, home care services such as home medical services, home nursing services, and telemedicine are required.

      Conclusions

      The sequelae of pneumonia or ARDS and CNS disorder as a cause for HMV and nasogastric tube feeding method were independently associated with early readmission. Respiratory events, such as aspiration, were associated with early readmission. Providing education focusing on respiratory care (suctioning and feeding methods) to caregivers is important for preventing early readmission.

      Institution and financial support

      None.

      Conflict of interest

      No potential conflict of interest relevant to this article was reported.

      Appendix. Supplementary materials

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