| Literature DB >> 33158837 |
Kathryn Eastwood1,2, Dhanya Nambiar3, Rosamond Dwyer3, Judy A Lowthian3,4, Peter Cameron3, Karen Smith3,2.
Abstract
BACKGROUND: Most calls to ambulance result in emergency ambulance dispatch (direct dispatch) following primary telephone triage. Ambulance Victoria uses clinician-led secondary telephone triage for patients identified as low-acuity during primary triage to refer them to alternative care pathways; however, some are returned for ambulance dispatch (secondary dispatch). Older adult patients are frequent users of ambulance services; however, little is known about the appropriateness of subsequent secondary dispatches.Entities:
Keywords: epidemiology; geriatric medicine; quality in health care; rationing; telemedicine
Mesh:
Year: 2020 PMID: 33158837 PMCID: PMC7651717 DOI: 10.1136/bmjopen-2020-042351
Source DB: PubMed Journal: BMJ Open ISSN: 2044-6055 Impact factor: 2.692
Definitions of the variables of interest
| Variables of interest | Definition |
| Age | The biological age of the patient at the time of the interaction with AV. Categorised into 5-year increments to 90 years. |
| Gender | The biological sex of the patient. Categorised as male and female. |
| Primary diagnosis | The final paramedic diagnosis category recorded in ePCR following paramedic clinical assessment. These are a broad symptom groups. |
| Local Government Area (LGA) | Identified through patient residential postcodes. The median income for each LGA reported by the Australian Bureau of Statistics was used to compare the LGA median income to the median income of all metropolitan Melbourne in 2011/2012 as a proxy for socioeconomic status. LGAs were classed has being ‘above’ or ‘below’ the median income of metropolitan Melbourne. |
| Vital signs | The physiological measurements obtained by paramedics. Vital signs were classed as ‘normal’ or ‘abnormal (low or high)’ as indicated below. The vital signs were categorised as follows: |
| Initial pulse rate (beats/min): 0–59 (abnormal - low), 60–99 (normal) and 100–248 (abnormal - high) | |
| Systolic blood pressure: 0–99 (abnormal - low), 100–139 (normal) and 140 and above (abnormal - high) | |
| Glasgow Coma Scale: 3–9 (abnormal), 10–14 (abnormal) and 15 (normal) | |
| Time of day | Aligned with the common paramedic ‘day-shift ‘of 0700–1700 hours or ‘night-shift’ of 1700–0700 hours |
| Weighted Charlson Comorbidity Index (WCCI) | The WCCI is a method of categorising comorbidities using the International Classification of Diseases diagnosis codes. The comorbidity categories are weighted from 1 to 6 based on the adjusted risk of mortality or resource use. The comorbidity score is the sum of all the weights. The WCCI was calculated and categorised using methods published by Charlson |
| Highest dispatch code | Code 1: immediate emergency ambulance dispatch using lights and sirens; arrival at the case within 15 min. |
| Code 2: immediate emergency ambulance dispatch with no lights or sirens. Obey all road rules and arrive within 25–30 min. | |
| Code 3: low-acuity dispatches, arrival to the patient within 60 min. Ambulance will be diverted if a more acute case arises closer to them | |
| Initial pain score | During clinical assessment, patients were asked to rank any pain on a continuous scale of 0–10, categorised as: |
| 0 (no pain) | |
| 1–2 (mild: does not require treatment) | |
| 3–6 (medium: requires treatment) and | |
| 7–10 (high: requires treatment) |
ePCR, electronic patient care record.
Figure 1Distribution of older patients to direct and secondary dispatch pathways and study inclusion. ePCR, electronic patient care record.
Patient demographics and clinical information: direct dispatch versus secondary dispatch for all Ambulance Victoria (AV) patients over 65 years who were diagnosed with one of five common paramedic diagnoses between 2009 and 2012 (N=90 086)
| Total | Direct dispatch (N=85 324) | Secondary dispatch (N=4762) | ||||
| N | % | N | % | N | % | |
| Age (years) | ||||||
| 65–69 | 13 139 | 14.6 | 12 458 | 15 | 681 | 14 |
| 70–74 | 14 811 | 16.4 | 13 954 | 16 | 857 | 18 |
| 75–79 | 17 446 | 19.4 | 16 503 | 19 | 943 | 20 |
| 80–84 | 19 749 | 21.9 | 18 693 | 22 | 1056 | 22 |
| 85–89 | 15 813 | 17.6 | 14 984 | 18 | 829 | 17 |
| 90–107 | 9128 | 10.1 | 8732 | 10 | 396 | 8.3 |
| Gender | ||||||
| Female | 51 817 | 57.5 | 49 183 | 58 | 2634 | 55 |
| Male | 38 269 | 42.5 | 36 141 | 42 | 2128 | 45 |
| Normal vital signs | ||||||
| Initial pulse rate | ||||||
| 60–99/min | 72 424 | 80.4 | 68 470 | 80 | 3954 | 83 |
| Initial systolic blood pressure | ||||||
| 100–139 mm Hg | 34 872 | 38.7 | 32 925 | 39 | 1947 | 41 |
| Initial GCS | ||||||
| 15 | 78 078 | 86.7 | 73 856 | 87 | 4222 | 89 |
| Initial pain score | ||||||
| no pain | 33 293 | 37 | 31 281 | 37 | 2012 | 42 |
| 1–3 | 15 544 | 17.3 | 14 850 | 17 | 694 | 15 |
| 4–6 | 21 877 | 24.3 | 21 026 | 25 | 851 | 18 |
| 7–10 | 19 372 | 21.5 | 18 167 | 21 | 1205 | 25 |
| WCCI | ||||||
| 0 | 27 291 | 30.3 | 25 812 | 30 | 1479 | 31 |
| 1–2 | 46 565 | 51.7 | 44 120 | 52 | 2445 | 51 |
| 3 and above | 16 230 | 18 | 15 392 | 18 | 838 | 18 |
| LGA above median income for metropolitan Melbourne | ||||||
| No | 74 068 | 82.2 | 70 157 | 82 | 3911 | 82 |
| Paramedic diagnosis | ||||||
| Dizzy | 6119 | 6.8 | 5654 | 6.6 | 465 | 9.8 |
| Febrile | 4847 | 5.4 | 4369 | 5.1 | 478 | 10 |
| Gastrointestinal disorder | 9444 | 10.5 | 8867 | 10 | 577 | 12 |
| Pain | 64 068 | 71.1 | 61 207 | 72 | 2861 | 60 |
| Urinary tract infection | 5608 | 6.2 | 5227 | 6.1 | 381 | 8 |
| Treated | ||||||
| 43 432 | 48.2 | 41 834 | 49 | 1598 | 34 | |
| Transported | ||||||
| 80 238 | 89.1 | 76 024 | 89 | 4214 | 89 | |
| Highest dispatch code | ||||||
| 1 | 50 542 | 56.1 | 50 208 | 59 | 334 | 7 |
| 2 | 27 363 | 30.4 | 26 015 | 31 | 1348 | 28 |
| 3 | 12 163 | 13.5 | 9086 | 11 | 3077 | 65 |
| 4 (Non-emergency ambulance) | 18 | 0 | 15 | 0 | 3 | 0.1 |
| Time of day | ||||||
| Nightshift (1700–0700 hours) | 40 394 | 44.8 | 38 255 | 45 | 2139 | 45 |
GCS, Glasgow Coma Scale; LGA, Local Government Area; WCCI, Weighted Charlson Comorbidity Index.
Comparison of treatment and transport rates for paramedic diagnosis between direct dispatch and secondary dispatch patients N=90 086
| Total | Treated (N=43 432) | Transported (N=80 238) | ||||||||
| Direct ambulance dispatch (N=41 834) | Secondary ambulance dispatch (N=1598) | Direct ambulance dispatch (N=76 024) | Secondary ambulance dispatch (N=4214) | |||||||
| Paramedic diagnostic category | N | % | N | % | N | % | N | % | N | % |
| Pain | 64 068 | 71 | 35 521 | 58 | 1173 | 41 | 55 627 | 91 | 2566 | 89.7 |
| Gastrointestinal disorder | 9444 | 11 | 2922 | 33 | 192 | 33 | 7141 | 81 | 477 | 82.7 |
| Dizzy | 6119 | 6.8 | 1285 | 23 | 70 | 15 | 4751 | 84 | 393 | 84.5 |
| Febrile | 4847 | 5.4 | 1082 | 25 | 83 | 17 | 3863 | 88 | 431 | 90.2 |
| Urinary tract infection | 5608 | 6.2 | 1024 | 20 | 80 | 21 | 4642 | 89 | 347 | 91.1 |
Adjusted and unadjusted OR results for association between direct dispatch and secondary dispatch for treatment and transport
| Variables | Treatment | Transport | ||
| Unadjusted OR (95% CI) | Adjusted OR (95% CI) | Unadjusted OR (95% CI) | Adjusted OR (95% CI) | |
| Direct dispatch | Ref | |||
| Secondary dispatch | 0.52 (0.49 to 0.56)* | 0.51 (0.48 to 0.55)* | 0.94 (0.86 to 1.03) | 0.95 (0.86 to 1.04) |
| Paramedic diagnostic category | ||||
| Pain | Ref | |||
| Dizzy | 0.21 (0.20 to 0.23)* | 0.39 (0.37 to 0.42)* | 0.53 (0.50 to 0.57)* | 0.87 (0.80 to 0.94)* |
| Febrile | 0.24 (0.22 to 0.25)* | 0.38 (0.36 to 0.41)* | 0.78 (0.72 to 0.86)* | 1.14 (1.03 to 1.25)* |
| Gastrointestinal problem | 0.37 (0.35 to 0.39)* | 0.51 (0.49 to 0.54)* | 0.42 (0.40 to 0.45)* | 0.601 (0.57 to 0.65)* |
| Urinary tract infection | 0.18 (0.17 to 0.2)* | 0.29 (0.27 to 0.32)* | 0.81 (0.75 to 0.89)* | 1.14 (1.04 to 1.25)* |
| Gender | ||||
| Female | Ref | |||
| Male | 1.20 (1.17 to 1.23)* | 1.25 (1.21 to 1.29)* | 1.16 (1.11 to 1.21)* | 1.13 (1.08 to 1.19)* |
| Age | ||||
| 60–69 | Ref | |||
| 70–74 | 0.95 (0.90 to 0.99)** | 0.97 (0.92 to 1.02) | 1.05 (0.97 to 1.13) | 1.02 (0.94 to 1.10) |
| 75–79 | 0.82 (0.78 to 0.85)* | 0.88 (0.83 to 0.92)* | 1.06 (0.98 to 1.13) | 1.06 (0.99 to 1.15) |
| 80–84 | 0.76 (0.73 to 0.80)* | 0.84 (0.80 to 0.89)* | 1.08 (1.01 to 1.16)** | 1.11 (1.03 to 1.19)* |
| 85–89 | 0.72 (0.68 to 0.75)* | 0.82 (0.78 to 0.87)* | 1.15 (1.07 to 1.24)* | 1.21 (1.12 to 1.31)* |
| 90–107 | 0.62 (0.59 to 0.65)* | 0.76 (0.72 to 0.81)* | 1.18 (1.08 to 1.29)* | 1.33 (1.21 to 1.45)* |
| LGA above median | ||||
| No | Ref | |||
| Yes | 1.08 (1.04 to 1.11)* | 1.16 (1.12 to 1.21)* | 1.03 (0.97 to 1.09) | 1.04 (0.99 to 1.11) |
| Day shift (0700–1700 hours) | ||||
| No | Ref | |||
| Yes | 1.12 (1.07 to 1.13)* | 1.01 (0.98 to 1.04) | 0.84 (0.80 to 0.87)* | 0.76 (0.73 to 0.79)* |
| Weighted Charlson Comorbidity Index | ||||
| 0 | Ref | |||
| 1 to 2 | 1.22 (1.17 to 1.24)* | 1.28 (1.24 to 1.33)* | 1.47 (1.41 to 1.54)* | 1.46 (1.39 to 1.53)* |
| 3 and above | 1.35 (1.30 to 1.41)* | 1.49 (1.42 to 1.52)* | 2.34 (2.19 to 2.51)* | 2.30 (2.14 to 2.48)* |
| Abnormal vital signs | ||||
| No | Ref | |||
| Yes | 1.39 (1.35 to 1.43)* | 1.51 (1.46 to 1.56)* | 1.97 (1.88 to 2.05)* | 1.96 (1.88 to 2.05)* |
| Initial pain score | ||||
| 0 | Ref | |||
| 1 | 1.10 (1.05 to 1.14)* | 0.82 (0.78 to 0.86)* | 0.66 (0.62 to 0.69)* | 0.68 (0.64 to 0.71)* |
| 2 | 3.82 (3.69 to 3.96)* | 2.54 (2.44 to 2.64)* | 2.16 (2.03 to 2.29)* | 2.20 (2.06 to 2.35)* |
| 3 | 6.07 (5.84 to 6.31)* | 4.11 (3.93 to 4.29)* | 9.89 (8.82 to 11.09)* | 10.42 (9.26 to 11.72)* |
**p<0.001; *p<0.005
LGA, Local Government Area.