Table 1
Patient demographics and triage characteristics.
| CHARACTERISTIC | OVERALL | INTUBATION | NIPPV |
|---|---|---|---|
| N = 46 | N = 27 (58.7%) | N = 23 (50.0%) | |
| Age, mean ± SD | 31.41 ± 21.42 | 27.52 ± 20.77 | 37.43 ± 22.86 |
| Age <1 year, n (%) | 3 (6.5%) | 3 (11.1%) | 0 (0.0%) |
| Age 1–4 years, n (%) | 2 (4.3%) | 2 (7.4%) | 1 (4.3%) |
| Age 5–17 years, n (%) | 9 (19.6%) | 4 (14.8%) | 5 (21.7%) |
| Age 18–24 years, n (%) | 4 (8.7%) | 2 (7.4%) | 2 (8.7%) |
| Age 25–34 years, n (%) | 7 (15.2%) | 7 (25.9%) | 1 (4.3%) |
| Age 35–44 years, n (%) | 7 (15.2%) | 2 (7.4%) | 5 (21.7%) |
| Age 45–54 years, n (%) | 9 (19.6%) | 5 (18.5%) | 5 (21.7%) |
| Age >55 years, n (%) | 5 (10.9%) | 2 (7.4%) | 4 (17.4%) |
| Female, n (%) | 27 (58.7%) | 15 (55.6%) | 14 (60.9%) |
| Comorbiditiesa,b | n = 41 | n = 23 | n = 22 |
| Any comorbidity, n (%) | 21 (51.2%) | 9 (39.1%) | 13 (59.1%) |
| Diabetes | 3 (7.3%) | 3 (13.0%) | 0 (0.0%) |
| Kidney disease | 2 (4.9%) | 0 (0.0%) | 2 (9.1%) |
| Hypertension | 3 (7.3%) | 1 (4.3%) | 2 (9.1%) |
| Congestive heart failure | 8 (19.5%) | 0 (0.0%) | 8 (36.4%) |
| Asthma | 4 (9.8%) | 3 (13.0%) | 2 (9.1%) |
| Tuberculosis | 1 (2.4%) | 1 (4.3%) | 0 (0.0%) |
| Other | 1 (2.4%) | 1 (4.3%) | 0 (0.0%) |
| Number of comorbidities, mean ± SD | 0.54 ± 0.55 | 0.39 ± 0.50 | 0.64 ± 0.58 |
| SATS triage levela, n (%) | n = 41 | n = 23 | n = 20 |
| Red (highest priority) | 30 (73.2%) | 17 (73.9%) | 15 (75.0%) |
| Orange | 9 (22.0%) | 5 (21.7%) | 4 (20.0%) |
| Yellow | 2 (4.9%) | 1 (4.3%) | 1 (5.0%) |
| Green (lowest priority) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) |
| Visit due to trauma, n (%) | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) |
| Triage vitals | |||
| Systolic blood pressure | n = 33 | n = 17 | n = 18 |
| mmHg, mean ± SD | 133.52 ± 39.65 | 120.24 ± 26.60 | 144.78 ± 44.96 |
| Patient hypotensivec, n (%) | 6 (18.2%) | 4 (23.5%) | 2 (11.1%) |
| SpO2 | n = 42 | n = 24 | n = 22 |
| %, mean ± SD | 85.12 ± 18.05 | 84.54 ± 21.70 | 85.00 ± 13.64 |
| SpO2 <90%, n (%) | 20 (47.6%) | 10 (41.7%) | 12 (54.5%) |
[i] SATS, South African Triage Scale; SpO2, oxygen saturation.
a Excludes patients with missing data.
b No patients were reported to have comorbid HIV, epilepsy, or stroke.
c Hypotension was defined as SBP <100 for age >12 years, <80 for ages 1–12, and <70 for <1 year old.
Table 2
Presenting diagnosis and indications for advanced respiratory support.
| CHARACTERISTIC | OVERALL | INTUBATION | NIPPV |
|---|---|---|---|
| N = 46 | N = 27 (58.7%) | N = 23 (50.0%) | |
| Presumed diagnosis at time of respiratory supporta, n (%) | |||
| Cardiovascular | 16 (34.8%) | 4 (14.8%) | 13 (56.5%) |
| Cardiogenic pulmonary edema | 12 (26.1%) | 1 (3.7%) | 11 (47.8%) |
| Cardiogenic shock | 3 (6.5%) | 0 (0.0%) | 3 (13.0%) |
| Pulmonary embolism | 1 (2.2%) | 0 (0.0%) | 1 (4.3%) |
| Hypovolemic shock | 3 (6.5%) | 3 (11.1%) | 1 (4.3%) |
| Hypertensive emergency | 2 (4.3%) | 0 (0.0%) | 2 (8.7%) |
| Respiratory | 10 (21.7%) | 5 (18.5%) | 6 (26.1%) |
| Severe asthma | 6 (13.0%) | 4 (14.8%) | 3 (13.0%) |
| Acute respiratory distress syndrome | 2 (4.3%) | 1 (3.7%) | 1 (4.3%) |
| Pulmonary hemorrhage | 1 (2.2%) | 0 (0.0%) | 1 (4.3%) |
| COPD | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) |
| Infectious | 13 (28.3%) | 12 (44.4%) | 3 (13.0%) |
| Pneumonia or pulmonary sepsis | 7 (15.2%) | 6 (22.2%) | 3 (13.0%) |
| Bacterial infection (unspecified) | 2 (4.3%) | 2 (7.4%) | 0 (0.0%) |
| Hematological | 2 (4.3%) | 2 (7.4%) | 0 (0.0%) |
| Neurological | 2 (4.3%) | 2 (7.4%) | 0 (0.0%) |
| Endocrine | 3 (6.5%) | 3 (11.1%) | 0 (0.0%) |
| Other | 3 (6.5%) | 2 (7.4%) | 1 (4.3%) |
| Indication for advanced respiratory supporta, n (%) | |||
| Hypoxia | – | 11 (40.7%) | 15 (65.2%) |
| CO2 retention | – | 4 (14.8%) | 0 (0.0%) |
| Respiratory distress | – | 2 (7.4%) | 8 (34.8%) |
| Respiratory arrest | – | 8 (29.6%) | – |
| Cardiac arrest | – | 2 (7.4%) | – |
| Airway protection | – | 12 (44.4%) | – |
| Airway obstruction | – | 3 (11.1%) | – |
| Other | – | 1 (3.7%) | 0 (0.0%) |
[i] COPD, chronic obstructive pulmonary disease. CO2, carbon dioxide.
a Multiple presumed diagnoses and indications for respiratory support could be selected for a patient.
Table 3
Pre-NIPPV monitoring and NIPPV success.
| CHARACTERISTICa | NIPPV |
|---|---|
| N = 23 | |
| Last vitals prior to NIPPV | |
| Systolic blood pressure, mean ± SD (n = 17) | 123.24 ± 61.82 |
| Patient hypotensiveb, n (%) | 4 (23.5%) |
| SpO2 (%), mean ± SD | 88.96 ± 8.90 |
| SpO2 <90%, n (%) | 13 (56.5%) |
| On monitoring prior to NIPPV, n (%) | 23 (100.0%) |
| SpO2 monitoring, n (%) | 22 (95.7%) |
| Blood pressure monitoring, n (%) | 15 (65.2%) |
| Cardiac monitoring, n (%) | 4 (17.4%) |
| Diagnostics and findings prior to NIPPV | |
| Chest X-ray, n (%) | 5 (21.7%) |
| Bilateral infiltrates (n = 3) | 2 (66.7%) |
| Pulmonary edema (n = 3) | 1 (33.3%) |
| Ultrasound, n (%) | 15 (65.2%) |
| B lines (n = 11) | 7 (63.6%) |
| Pleural effusion (n = 11) | 2 (18.2%) |
| Cardiac finding (n = 11) | 2 (18.2%) |
| Blood gas obtained, n (%) | 7 (30.4%) |
| NIPPV type, n (%) | |
| CPAP | 1 (4.3%) |
| BiPAP | 22 (95.7%) |
| Patient respiratory status 30 minutes following NIPPV, n (%) | |
| Improved | 16 (69.6%) |
| Unchanged or worsened | 7 (30.4%) |
| SpO2 <90% prior to NIPPV, n (%) | 13 (56.5%) |
| Achieved SpO2 >90% after NIPPV, n (%) | 11 (84.6%) |
| Patient required intubation, n (%) (n = 20) | 4 (20.0%) |
| NIPPV discontinued during time in ED, n (%) (n = 19) | 2 (10.5%) |
[i] SpO2, oxygen saturation; CPAP, continuous positive airway pressure; BiPAP, bi-level positive airway pressure.
a For characteristics with missing information, the number of patients with available information is noted in parentheses.
b Hypotension was defined as SBP <100 for age >12 years, <80 for ages 1–12, and <70 for <1 year old.
Table 4
Pre-intubation management and intubation characteristics and complications.
| CHARACTERISTICa | INTUBATION |
|---|---|
| N = 27 | |
| Preoxygenation before intubation, n (%) (n = 26) | 26 (100.0%) |
| Nasal cannula | 2 (7.7%) |
| Non-rebreather mask | 4 (15.4%) |
| Simple face mask | 4 (15.4%) |
| BiPAP | 2 (7.7%) |
| Bag valve mask, passive | 2 (7.7%) |
| Bag valve mask, active | 9 (34.6%) |
| Other | 3 (11.5%) |
| Last vitals prior to intubation | |
| Systolic blood pressure, mean ± SD (n = 17) | 132.06 ± 40.70 |
| Patient hypotensiveb, n (%) | 3 (17.6%) |
| SpO2 (%), mean ± SD (n = 22) | 94.50 ± 7.95 |
| SpO2 <90%, n (%) | 3 (13.6%) |
| Blood gas obtained, n (%) | 10 (37.0%) |
| pH, mean ± SD (n = 7) | 6.99 ± 0.49 |
| CO2, mean ± SD (n = 7) | 52.73 ± 23.68 |
| Formal difficult airway assessment completed, n (%) | 13 (48.1%) |
| Difficult airway anticipatedc,d, n (%) | 10 (37.0%) |
| Number of risk factors for difficult airwaye, mean ± SD | 0.89 ± 1.60 |
| Operator on initial attempt | |
| EM intern | 1 (3.7%) |
| EM second-year resident | 16 (59.3%) |
| EM third-year resident | 10 (37.0%) |
| EM-trained attending | 0 (0.0%) |
| Operator on successful attempt (if 1st attempt unsuccessful) | |
| Same as initial attempt | 2 (7.4%) |
| EM intern or second-year resident | 1 (3.7%) |
| EM third-year resident | 6 (22.2%) |
| EM-trained attending | 2 (7.4%) |
| First-pass success, n (%) (n = 26) | 15 (57.7%) |
| Among second-year residents | 9 (60.0%) |
| Among third-year residents | 6 (60.0%) |
| Total number of attempts, mean ± SD | 1.75 ± 0.94 |
| Overall intubation success, n (%) (n = 26) | 26 (100.0%) |
| Any induction agent administeredf, n (%) (n = 22) | 19 (86.4%) |
| Ketamine | 16 (72.7%) |
| Midazolam | 2 (9.1%) |
| Propofol | 1 (4.5%) |
| Fentanyl | 1 (4.5%) |
| Any paralytic agent administeredg, n (%) (n = 22) | 15 (68.2%) |
| Succinylcholine | 10 (45.5%) |
| Vecuronium | 5 (22.7%) |
| Both induction and paralytic agents administered, n (%) (n = 21) | 15 (71.4%) |
| Lowest O2 saturation during intubation (%), mean ± SD (n = 23) | 93.61 ± 7.33 |
| Lowest O2 saturation <90%, n (%) | 4 (17.4%) |
| Any method of intubation confirmationh, n (%) (n = 21) | 21 (100.0%) |
| Auscultation | 21 (100.0%) |
| Tube condensation | 13 (61.9%) |
| Radiography | 2 (9.5%) |
| CO2 detector | 0 (0.0%) |
| Any complicationi, n (%) (n = 26) | 2 (7.7%) |
| Bleeding | 1 (3.8%) |
| Hypoxia (SpO2<90%) | 1 (3.8%) |
[i] BiPAP, bi-level positive pressure ventilation; SpO2, oxygen saturation; CO2, carbon dioxide.
a For characteristics with missing information, the number of patients with available information is noted in parentheses.
b Hypotension was defined as SBP <100 for age >12 years, <80 for ages 1–12, and <70 for <1 year old.
c Difficult airway was defined as an abnormal LEMON assessment, if LEMON assessment was completed; if assessment was not completed, difficult airway included Mallampati Class III/IV; spinal immobilization; or obese body habitus.
d The LEMON method is an airway assessment defined by the following criteria: Look, Evaluate, Mallampati, Obesity or obstruction, and Neck mobility.
e Risk factors included external evaluation, 3-3-2, Mallampati score (3 or 4), obesity, and neck immobility/spinal immobilization.
f No providers reported using lorazepam, etomidate, or morphine for induction.
g Rocuronium is not available for use at HUM.
h Multiple methods of confirmation could be selected.
i No providers reported complications of direct airway injury, cardiac arrest, cricothyroidotomy, dental trauma, hypotension, or laryngospasm.
Figure 1
Flowchart of patients presenting with respiratory failure to the HUM ED.
a Patient remained in the ED for 3 days prior to stabilization and transfer to the general ward.
Table 5
Bivariate analysis of factors associated with survival to discharge.
| NIPPV | INTUBATION | |||||||
|---|---|---|---|---|---|---|---|---|
| n | SURVIVED TO DISCHARGE | DID NOT SURVIVE TO DISCHARGE | P VALUEa | n | SURVIVED TO DISCHARGE | DID NOT SURVIVE TO DISCHARGE | P VALUEa | |
| N = 12 | N = 11 | N = 6 | N = 21 | |||||
| Age | ||||||||
| Age <5 years | n = 1 | 1 (100.0%) | 0 (0.0%) | 0.328 | n = 5 | 1 (20.0%) | 4 (80.0%) | 0.895 |
| Age 5–18 years | n = 5 | 2 (40.0%) | 3 (60.0%) | 0.538 | n = 4 | 1 (25.0%) | 3 (75.0%) | 0.885 |
| Age >18 years | n = 17 | 9 (52.9%) | 8 (47.1%) | 0.901 | n = 18 | 4 (22.2%) | 14 (77.8%) | 1.000 |
| Female gender | n = 14 | 6 (42.9%) | 8 (57.1%) | 0.265 | n = 15 | 5 (33.3%) | 10 (66.7%) | 0.121 |
| Comorbidities | ||||||||
| Congestive heart failure | n = 8 | 2 (25.0%) | 6 (75.0%) | 0.035 | – | – | – | – |
| Asthma | n = 2 | 2 (100.0%) | 0 (0.0%) | 0.176 | n = 3 | 3 (100.0%) | 0 (0.0%) | 0.002 |
| High priority triage acuityb | n = 19 | 10 (52.6%) | 9 (47.4%) | 0.305 | n = 22 | 4 (18.2%) | 18 (81.8%) | 0.639 |
| Presumed diagnosis | ||||||||
| Cardiovascular | n = 13 | 4 (30.8%) | 9 (69.2%) | 0.019 | n = 4 | 1 (25.0%) | 3 (75.0%) | 0.885 |
| Respiratory | n = 6 | 5 (83.3%) | 1 (16.7%) | 0.076 | n = 5 | 4 (80.0%) | 1 (20.0%) | <0.001 |
| Infectious | n = 3 | 2 (66.7%) | 1 (33.3%) | 0.590 | n = 12 | 1 (8.3%) | 11 (91.7%) | 0.121 |
| On SpO2 monitoring prior to NIPPV | n = 22 | 12 (54.5%) | 10 (45.5%) | 0.286 | – | – | – | – |
| Trial of NIPPV before intubation | – | – | – | – | n = 7 | 4 (57.1%) | 3 (42.9%) | 0.010 |
| Initial operator first- or second-year resident | – | – | – | – | n = 17 | 3 (17.6%) | 14 (82.4%) | 0.456 |
[i] SpO2, oxygen saturation.
a P-values were calculated using chi-squared tests.
b High priority triage acuity includes red and orange triage levels. Excludes patients who had missing data on South African Triage Scale triage level.