Epidemiology of NIV for Acute Respiratory Failure in COPD Patients: Results from the International Surveys vs. the “Real World”

Figures & data

Table 1. Results of survey studies regarding the use of NIV in AECOPD.

Author	Year	Response rate	NIV utilization population/region	Conclusion regarding NIV Use in AECOPD
Vanpee (17)	2002	98/145 MDs	AECOPD/98 EDs of Belgium	NIV use: In 49% of the ED's. Only 3.8% of MD's doubted the benefit of NIV.
				Main barriers of not using NIV: Lack of equipment (71%) or experience (32.7%), more time consuming for the staff (22.8%).
				Pressure-controlled ventilators (Home type) used more than volume-controlled ventilators.
Burns (18)	2005	385/808 MDs and residents in four specialties	All ARF patients/ 15 teaching hospitals of Canada	Overall NIV use: By 62.8% of the respondents; in monitored settings (94%)
				Most common indication (% of respondents): AECOPD (95.5%)
				Perceived efficacy of NIV for AECOPD: Beneficial (91.3%), no net benefit (1.7%), harmful (3.3%), uncertain (2.1%)
				Independent predictor of NIV use for AECOPD: awareness of literature
Drummond (19)	2005	33/33 hospitals	AECOPD/33 teaching hospitals of Canada	NIV availability: 100%; Routine use: 61% (40–100% range by region)
				Location: Only in ED or ICU (70%), on general wards (18%)
				DNI patients: NIV offer rare/never by 32% of hospitals
Maheshwari (20)	2006	71/81 RTs	All ARF patients/71 acute care hospitals of US	Overall NIV use: 20% of ventilator starts; at ICU (55%), ED (26%) or wards (18%)
				Most common indications: AECOPD and CHF (82% of NIV use)
				Only 1/3of AECOPD received NIV
Browning (21)	2006	222/233	All ARF patients/222 EDs of UK	Overall NIV use: 67% of ED's
		EDs		Most common indications (% of ED's): AECOPD (77%) and CHF (86%)
Devlin (13)	2007	790/2,985 MDs	All ARF patients/790 MDs two continents)	Overall NIV use >25% of ARF patients: 44% (Europeans> Americans);
				NIV use>25% of AECOPD: 84% of respondents
Stone (22)	2009	100/301 Hospitals	AECOPD/100 UK NHS Trusts	NIV as 1st line treatment: 80% of responders; at designated areas with trained staff (ICU, HDU, ED or ward) (74%responders)
Hess (31)	2009	238/264 RT+MDs	AECOPD, CHF, Asthma/119 academic EDs, US	Familiarity with NIV: 64% of MD's, 99% of RT's
				NIV use >20% of AECOPD: 66% (of respondents); <10% of AECOPD: 17%
				Majority of MD's and RT's (>95%) reported that NIV often helps for AECOPD.
Bierer (23)	2009	192/882 RT+MDs	All ARF patients/ICUs of 63 VA hospitals, US	NIV as 1st line for AECOPD: 76%; No restriction on location of use: 43%
				75% of respondents reported <50% of patients treated with NIV when indicated.
				29% of respondents reported perceived NIV success rate>50%
				RT's reported more NIV underutilization and failure as compared to MD's.
Crimi (24)	2010	272/530 MDs	All ARF patients/25 European countries	Overall NIV utilization rate>20% by 81% of respondents (pulmonologists>other specialists)
				Most common indication: AHRF (48% of total NIV use) (pulmonologists>intensivists)
Ozsancak (28)	2015	596/2,205 MDs	All ARF patients/596 MDs of Turkey	Overall NIV utilization: By 71% of respondents
				Most common indication: AECOPD (99.5%); 62% of respondents use NIV >80% of AECOPD; mostly at general wards (86% of respondents) and ICU's (70%); Estimated success rate for AECOPD>60% by 94% of respondents.
Cabrini (26)	2015	157 hospitals	All ARF patients/51 countries (five continents)	Overall NIV use at general wards: 66% of respondents
				Most common indication for NIV use outside the ICU: AECOPD (94%)
				Overall perceived NIV success rate (wards)>50% by 51% of respondents.

AECOPD, acute exacerbation of chronic obstructive pulmonary disease; AHRF, acute hypercapnic respiratory failure; ARF, acute respiratory failure; CHF, congestive heart failure; DNI, do-not-intubate; ED, emergency department; HDU, high dependency unit; ICU, intensive care unit; MD, medical doctor; NIV, non-invasive ventilation; RT, respiratory therapist.

Table 2. Results of studies analyzing: (a) inpatient datasets regarding the use of NIV in AECOPD and (b) observational cohorts regarding the use of NIV in AECOPD (published in last decade).

(a)
			AECOPD
Author	Data Source	Population/Duration	Requiring MV	Initial NIV Start for AECOPD	Conclusion Regarding NIV Use in AECOPD
Chandra (6)	NIS	Hospitalized AECOPD (7,511,267) 1998–2008	612,650 (8.1%)	3% of all admissionsNearly 38% of all ventilator startsChange: NIV: 1% to 4.5% (462%)IMV: 6% to 3.5% (42%)	NIV failure rate: Around 5% of NIV patientsIn-hospital mortality, LOS and costs: NIV failure>IMV>NIV onlyDemographics and co-morbidities- similar in yearsPts > 75 yo- initiated more core commonly on NIV
Walkey (38)	NIS	Hospitalized ARF (2,380,632)2000–2009	900,750 (37%);7% increase in AECOPD	Change:NIV: 3.5 to 12.3% (250%)	Among NIV users, most common diagnosis: COPD (53%)NIV failure in AECOPD: 13.4%Greater hospital mortality in NIV failure (OR 1.11)
Tsai (40)	NEDS	Hospitalized AECOPD with ARF (67,651)2006–2008(ED + inpatient)	43%	NIV use (including NIV failure): 11% (0–100%)ChangeNIV only: 14% to 16%IMV only: 28% to 19%	NIV + IMV patients associated with more co-morbidities and higher inpatient mortality, LOS and cost.In a propensity score analysis, NIV use, compared with IMV:-Decreased inpatient mortality (risk ratio: 0.54),- Shortened LOS (−3.2 days) – Decreased cost (−$35,012)- Decreased risk of iatrogenic pneumothorax (0.05% vs. 0.5%)
Stefan (7)	NIS	Hospitalized AECOPD(723,560)2001–2011	18.20%4.4% annual raise	10.6% of all admissions59.2% of all ventilator startsChange:NIV: 5.9% to 14.8% (39.9% to 71.7% of ventilator starts); IMV: 8.7% to 5.9%	NIV failure Decreased: 17.9% to 16.7%Older pts > 75 yo: less MV, more NIV, less NIV failure, faster increase in NIV use, and decrease in IMV use.Increased number of co-morbidities(>4) and presence of pneumonia were associated with less NIV use, and more NIV failure and IMV use.
Lindenauer (41)	PID	AECOPD with ARF receiving MV on 1st2 days of stay(25,628)2008–2011	16.6% of all AECOPD admissions	70.1% of all ventilator starts (34–87)NIV start- associated with older age, previous admission for AECOPD, less co-morbidity.	NIV failure: 15.3%; Presence of more co-morbidities and pneumonia decreased the advantage of NIV.In a propensity score analysis, NIV use, compared with IMV:In a propensity score analysis, NIV use, compared with IMV:‐ Decreased inpatient mortality (risk ratio: 0.54),‐ Shortened LOS (19%) – Decreased cost (32%)‐ Decreased risk of hospital acquired pneumonia (risk ratio: 0.53)
Stefan (42)	Apache	ICU admissions of AECOPD(3,520)2008–2012	73.9%	37.4% of all ventilator startsNIV start- associated with less SAPS II, more ED admissions and DNR status	NIV failure: 13.7%; Predictors: SAPS II score and presence of cancer; Associated with higher mortality.In propensity matched analysis, NIV use, compared with IMV:‐ Decreased inpatient mortality (41%)
Lindenauer (43)	PID	Hospitalized AECOPD (102654)2009–2011	27.4%	15.1% of all admissions72.6% of all ventilator starts (9–94%)	NIV failure: 15.5%As risk-standardized % of ventilator starts as NIV increase (47.4–84.7%):‐ Decrease in rate of IMV, -Modest increase in total MV,‐ Similar rate of NIV failure, -Decrease in cost ($3000) and LOS (1 day)

   

Mehta (44)	CSID	Hospitalized AECOPD(37,516) 2011	16.2%	9.3% of all admissions57.4% of all ventilator starts	NIV failure: 10.4%; Associated with co-morbidities and acute organ failures at admission. Higher hospital NIV case volume: associated with higher NIV failure (and higher mortality rates).
Stefan (55)	PID	AECOPD treated with NIV (13893) 2009–2011			NIV failure: 15.2%, In-hospital mortality: 6.5%Higher NIV case volume: Not associated with NIV failure, in-hospital mortality, 30-day readmission, hospital LOS.
Toft-Petersen (8)	Danish	Hospitalized AECOPD (173,456 pts) 2000–2012	9.7%	NIV only: Increased 4.6-foldNIV + IMV: Increased 3.1-foldIMV only: Decreased 40%	(NIV + IMV)/NIV: Decreased 25% to 20% (NIV failure? Post-extubation?)In-hospital mortality: IMV ± NIV (increased 32% to 38%)>NIV only (no change)
(b)
	Population/performance		Initial NIV start for
Author	duration	AECOPD cases	AECOPD	Conclusion regarding NIV use in AECOPD
Esteban (37)	1-mo prospective cohort of all ventilated pts (4968 pts)/349 ICU's in 2004Follow-up study of 1998 cohort	5% of all ventilated>12 hours in ICU	Overall NIV use: 4% to 11%For AECOPD: 16.4% to 44%	Proportion of patients with AECOPD: Decreased (10% to 5%)
Funk (45)	Retrospective analysis of prospective cohort of 194,453 pts/87 Austrian ICU between 1998 and 2008	2.5% of all pts as a cause of ARF, 6.1% as co-morbidity	For AECOPD: 14% to 50%IMV use: 62% to 58%	Increased proportion of ARF due to AECOPD: 1.8% to 3%The risk-adjusted mortality: (both COPD patients as co-morbidity or cause of ARF): Decreased substantially over time.
Wang (46)	Population-based retrospective cohort of 1461 pts admitted to ICU at Mayo Clinic, US in 2006.	1% of all admissions, 21% of all NIV pts	Overall NIV use: 40% of ventilated	Among NIV success, AECOPD pts (29%) were more commonMajor etiology for 37 pts with palliative NIV use: AECOPD (51%), with a higher hospital mortality rate than other AECOPD pts on NIV, even after adjusting for the baseline disease severity (32% vs. 0%)
Dres (47)	Regional database with retrospective cohort of 276,679 pts/35 French ICU's, between 1998 and 2010	5.2% of all admissions	Overall NIV use: 18.5% to 49.2%IMV use: 34.2% to 18.7%Any MV use: 64% to 86%	SAPS II and ICU mortality increased (36–41% and 12–14%, respectively)Higher ICU-case volumes: Associated with higher NIV use (OR 1.43) and lower mortality.
Schnell (48)	60-day prospective cohort of all ventilated pts (3163 pts)/14 French ICU's between 1997 and 2011	20.9% of all ventilated pts	Overall NIV use: 29% to 42% 1st line NIV use: 57.7% for AECOPD	Among AOCRF pts: NIV failure: 32% to 10%; 1st line NIV use associated with less 60-day mortality (adjusted HR: 0.71)Overall, predictors of NIV failure: Younger age, reason for admission, moresevere SAPS II and worse SOFA scores on days 1 and 2
Ozsancak (49)	30-day prospective cohort of all ventilated pts (548 pts)/8 US hospitals during 3 mo between 2004 and 2007	16.4% of all ventilated pts	Overall 1st line NIV use: 38.5% For AECOPD: 82.2%	NIV failure (including death and mask intolerance):25% (Intubation rate: 18%) In-hospital 30-day mortality:12.1%Major etiology for 44 pts with NIV use in pts with DNI: AECOPD (45.5%)
(Continued on next page)

Table 2. (Continued)

(b)
	Population/performance		Initial NIV start for
Author	duration	AECOPD cases	AECOPD	Conclusion regarding NIV use in AECOPD
Quanes (50)	Prospective cohort of all AECOPD pts (552 admissions)/1 Tunisian ICU between 2000 and 2012		1st line NIV use: 67.8% for AECOPD; increased 29% to 97%	NIV failure: 16.8 (Decreased 30% to 10%);Among NIV pts: VAP: 5.6%, ICU mortality:7%; both<IMV ptsICU mortality predictors: NIV failure, VAP, cardiovascular co-morbidities; 1st line NIV use was against fatal outcome.
Gacouin (51)	Retrospective analysis of prospective cohort of 1113 AOCRF pts initiated on MV in ICU or ED between 1998 and 2012	51% of all ventilated pts	For AECOPD: NIV only: 41%Rate of 1st line NIV use and NIV use- Increased (OR1.05)	NIV failure: 18.1%, Associated with higher rate of mortality>IMV>NIV onlyUse of NIV associated with lower rates of VAP (OR 0.41)
Demoule (52)	Prospective cohort of all ventilated pts (4132 pts)/54 French and Belgian ICU's during 2 mo's between 2010 and 2011. Follow-up of 1997 and 2002.	27.9% of all ARF pts (17.5%−1997, 19.3%−2002)	Overall 1st line NIV use: reached a plateau: 16% to 23–24%; Similarly for AOCRF: 50% to 64–65%.	Overall NIV failure: 40–44% to 30% in years; Predictors: SAPS II, de novo ARF and high levels of leaksAmong AOCRF pts: NIV use: Associated with lower mortality; NIV failure: not associated with higher mortality (consistent throughout 3 audits)
Roberts (56)	Retrospective analysis of prospective cohort of 9716 AECOPD pts/232 UK hospitals during 3 mo's in 2008. Follow-up study of 2003 Audit (39).	MV use: 9.7% of admissions	NIV use- increased from 7% to 11.1% of admissionsNIV start rate: 66% in pts with pH<7.26, 34% in pts with pH 7.26–7.34, 5% in non-acidotics	(NIV + IMV)/NIV = 4.2%Do-not-resuscitate order: 40% of NIV pts; Pneumonia present in 21% NIV ptsIn-hospital mortality for overall NIV: 25%; of acidotic pts any time during admission: 26% for NIV pts vs. 14% in non-NIV pts.Mortality worse in late-onset acidosis, NIV users and admission RR>30/minute

Abbreviations as in Table 1, additionally AOCRF, acute-on-chronic respiratory failure; CSID, California state inpatient database; IMV, invasive mechanical ventilation; LOS, length of stay; mo, month; MV, mechanical ventilation; NEDS, nationwide emergency department and inpatient sample; NIS, nationwide inpatient sample; PID, premier inpatient database; Pts, patients; VAP, ventilator associated pneumonia; yo, years old.

Figure 1. Trends in initial ventilation strategies among patients with ARF due to AECOPD. IMV, invasive mechanical ventilation; MV, mechanical ventilation; NIV, non-invasive ventilation. Reprinted from Stefan et al. (7). Copyright (2017), with permission from Elsevier.

Figure 2. Trends in ventilation use in COPD with and without pneumonia, 2001–2011. (A) Any ventilation. (B) Non-invasive ventilation. (C) Invasive ventilation. Reprinted from Stefan et al. (7). Copyright (2017), with permission from Elsevier.

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