The association between paramedic service system hospital offload time and response time

OBJECTIVE

To address an important care issue in Canada, we tested the association between paramedic system hospital offload and response time, while considering the impact of other system-level factors.

METHODS

Data from Calgary, Alberta (2014-2017), included median offload (exposure) and response (outcome) time aggregated by hour, with covariates paramedic system episodes of care-dispatch and arrival of a response unit-and hospital transport arrivals (collectively called volume), time of day, and season. Analyses used linear regression and modified Poisson models.

RESULTS

301,105 EMS episodes of care over 26,193 1-h periods were included. For any given 1-h period, the median (IQR) across all episodes of care for offload time, response time, episodes of care, and hospital transport arrivals were 55.3 (45.7, 66.3) min, 8.6 (7.6, 9.8) min, 12 (8, 16) episodes, and 8 (5, 10) hospital arrivals, respectively. Multivariable modelling revealed a complex association differing over levels of exposure and covariates, requiring description using "light stress" and "heavy stress" system scenarios. The light scenario was defined as median offload of 30 min and volume < 10th percentile (six episodes and four hospital arrivals), in the summer, and the heavy scenario as median offload of 90 min and volume > 90th percentile (17 episodes and 13 hospital arrivals), in the winter. An increase is reported in minutes:seconds for median hourly response time between scenarios by time of day: 1:04-4:16 (0000-0559 h.), 0:42-2:05 (0600-1159 h.), 0:57-3:01 (1200-1759 h.), and 0:18-2:21 (1800-2359 h.).

CONCLUSIONS

Increasing offload is associated with increased response time; however the relationship is complex, with a greater impact on response time noted in select situations such as high volume in the winter. These observations illustrate the interdependence of paramedic, ED, and inpatient systems and provide high-yield targets for polices to mitigate the risk to community availability of paramedic resources at times of high offload delay/system stress.

A46 ENTEROBACTERIACEAE ENRICHMENT IN THE GUT MICROBIOME OF CRITICALLY ILL PATIENTS PROMOTES IMMUNE DYSFUNCTION AND SUSCEPTIBILITY TO NOSOCOMIAL INFECTIONS

NOT PUBLISHED AT AUTHOR’S REQUEST

Linkage of Emergency Medical Services and Hospital Data: A Necessary Precursor to Improve Understanding of Outcomes of Prehospital Care

Objective: Linking emergency medical services (EMS) data to hospital outcomes is important for quality assurance and research initiatives. However, non-linkage due to missing or incomplete patient information may increase the risk of bias and distort findings. The purpose of this study was to explore if an optimization strategy, in addition to an existing linkage process, improved the linkage rate and reduced selection and information bias.Methods: 4,150 transported patients in a metropolitan EMS system in Alberta, Canada from 2016/17 were linked to two Emergency Department (ED) databases by a standard strategy using a unique health care number, date/time of ED arrival, and hospital name. An optimized strategy added additional linkage steps incorporating last name, year of birth, and a manual search. The strategies were compared to assess the rate of linkage, and to describe event and patient-level characteristics of unlinked records.Results: The standard strategy resulted in 3,650 out of 4,150 (88.0%) linked records (95% CI 86.9%-88.9%). Of the 500 non-linked records, an additional 381 were linked by the optimized strategy (n = 4,031/4,150 [97.1%; 95% CI: 96.6%-97.6%]). There were no false positive linkages. The highest linkage failure was in 25 to 34 year-old patients (n = 93/478, 19.5%), males (n = 236/1975, 12.0%), Echo level events (n = 15/77, 19.5%), and emergency transport (45/231, 19.5%). The optimized strategy improved linkage in these groups by 68.8% (64/93), 79.2% (187/236), 40.0% (6/15), and 51.1% (23/45) respectively. For dispatch card, the highest linkage failure occurred in Card 24-Pregnancy/Childbirth/Miscarriage (n = 30/44, 68.2%), Card 27-Stab/Gunshot/Penetrating Trauma (n = 6/17, 35.3%), and Card 9-Cardiac/Respiratory Arrest/Death (n = 12/46, 26.1%). The optimized strategy improved linkage by 10.0% (3/30), 83.3% (5/6), and 41.7% (5/12) respectively. For the 119 unlinked records, 71 (59.7%) had sufficient information for linkage, but no appropriately matching records could be found.Conclusion: An optimized sequential deterministic strategy linking EMS data to ED outcomes improved the linkage rate without increasing the number of false positive links, and reduced the potential for bias. Even with adequate information, some records were not linked to their ED visit. This study underscores the importance of understanding how data are linked to hospital outcomes in EMS research and the potential for bias.

The effectiveness of prehospital hypertonic saline for hypotensive trauma patients: a systematic review and meta-analysis

Background

The optimal prehospital fluid for the treatment of hypotension is unknown. Hypertonic fluids may increase circulatory volume and mute the pro-inflammatory response of the body to injury and illness. The purpose of this systematic review is to determine whether in patients presenting with hypotension in the prehospital setting (population), the administration of hypertonic saline (intervention), compared to an isotonic fluid (control), improves survival to hospital discharge (outcome).

Methods

Searches were conducted in Medline, Embase, CINAHL, and CENTRAL from the date of database inception to November, 2016, and included all languages. Two reviewers independently selected randomized control trials of hypotensive human participants administered hypertonic saline in the prehospital setting. The comparison was isotonic fluid, which included normal saline, and near isotonic fluids such as Ringer’s Lactate. Assessment of study quality was done using the Cochrane Collaborations’ risk of bias tool and a fixed effect meta-analysis was conducted to determine the pooled relative risk of survival to hospital discharge. Secondary outcomes were reported for fluid requirements, multi-organ failure, adverse events, length of hospital stay, long term survival and disability.

Results

Of the 1160 non-duplicate citations screened, thirty-eight articles underwent full-text review, and five trials were included in the systematic review. All studies administered a fixed 250 ml dose of 7.5% hypertonic saline, except one that administered 300 ml. Two studies used normal saline, two Ringer’s Lactate, and one Ringer’s Acetate as control. Routine care co-interventions included isotonic fluids and colloids. Five studies were included in the meta-analysis (n = 1162 injured patients) with minimal statistical heterogeneity (I² = 0%). The pooled relative risk of survival to hospital discharge with hypertonic saline was 1.02 times that of patients who received isotonic fluids (95% Confidence Interval: 0.95, 1.10). There were no consistent statistically significant differences in secondary outcomes.

Conclusions

There was no significant difference in important clinical outcomes for hypotensive injured patients administered hypertonic saline compared to isotonic fluid in the prehospital setting. Hypertonic saline cannot be recommended for use in prehospital clinical practice for the management of hypotensive injured patients based on the available data.

PROSPERO registration # CRD42016053385.

Renal recovery after severe acute renal failure

BACKGROUND

There is limited information about renal recovery to independence from renal replacement therapy (RRT) and about factors associated with its occurrence after severe acute renal failure (ARF).

METHODS

We conducted a population-based surveillance among all adult residents of the Calgary Health Region surviving ICU admission from May 1, 1999 to April 30, 2002. The primary objective was to determine the rate of and the factors associated with 90-day survival and recovery to independence from RRT in critically ill patients with severe ARF.

RESULTS

At 90 days, 96 patients (40%) were alive. Of these, 72% were RRT independent with most (87%) requiring <4 weeks to recover. Prior to RRT, the median (IQR) serum creatinine and mean (SD) serum urea were 395 (252-517) micromol/L and 29.2 (18) mmol/L, respectively. Oliguria was present in 76%. Intermittent hemodialysis was the initial modality in 46% and continuous renal replacement therapy (CRRT) in 54%. By multivariate analysis, male sex (odds ratio (OR) 7.6, 95% CI, 2.2-27, p=0.01) and a diagnosis of septic shock (OR 3.9, 95% CI 1.02-14.5, p=0.05) were associated with an increased odds of recovery. Conversely, a higher Charlson co-morbidity index score (OR 0.71, 95% CI, 0.6-0.85, p=0.04) and a higher pre-RRT serum creatinine (OR 0.20, 95% CI, 0.05-0.80, p=0.02, p=0.02) were associated with reduced odds of recovery. Chronic kidney disease or the initial modality of RRT were not associated with recovery.

CONCLUSIONS

The majority of severe ARF patients who survive their acute illness are independent of RRT by 90 days. Male sex and a diagnosis of septic shock are independently associated with recovery while a greater co-morbidity score and a higher serum creatinine prior to RRT are predictive of non-recovery.

Bloodstream infection-associated sepsis and septic shock in critically ill adults: a population-based study

BACKGROUND

Few studies have investigated the epidemiology of sepsis and septic shock in a large population and none have been from Canada. The objective of this study was to define the epidemiology of bloodstream infection (BSI)-associated sepsis and septic shock among all critically ill patients in a large, fully integrated health region in Canada.

PATIENTS AND METHODS

All critically ill adults admitted to multidisciplinary intensive care units (ICU) in the Calgary Health Region during May 1, 1999 to April 30, 2000 were included. Clinical, microbiologic and outcome information was obtained from regional databases.

RESULTS

We surveyed 1981 patients having at least one ICU admission. Systemic inflammatory response syndrome (SIRS) was diagnosed in 92%, BSI-associated sepsis (BSI with SIRS) in 6% and BSI-associated septic shock (BSI with SIRS and hypotension) in 3%; respective hospital mortality rates were 36%, 40% and 49%. The most common BSI etiologies were Staphylococcus aureus, Escherichia coli and Streptococcus species; only one isolate (1%) was highly antibiotic resistant. Independent risk factors for death among patients with SIRS included age (>or= 65), hypothermia (< 35 degrees C), and higher APACHE II and TISS scores. A surgical diagnosis was associated with decreased mortality risk. Neither a positive blood culture nor hypotension at presentation independently predicted death.

CONCLUSION

Knowledge of the epidemiology of these syndromes is important for assessing the burden of disease and providing background information for investigating new therapies.

Encephalopathy with staphylococcal endocarditis: multiple neuropathological findings

BACKGROUND

Infective endocarditis is associated with serious neurological sequelae.

OBJECTIVE

Here, we report a patient with Staphylococcus aureus endocarditis, secondary to congenital heart disease, with subacute onset of multiple neurological complications.

RESULTS

Despite prompt antibiotic treatment with rapid sterilization of blood cultures, the patient died with brain herniation within 96 hours of admission. Neuropathological examination showed intraparenchymal hemorrhages, mycotic aneurysms, micro-abscesses and septic arteritis with accompanying infarction. Immunocytochemical studies revealed enhanced CD45 and GFAP immunoreactivity, together with adenosine A1 receptor detection on macrophages and microglia.

CONCLUSIONS

Infective endocarditis is associated with multiple neuropathological lesions, which may contribute to its poor clinical outcome and activation of cells of monocyte-microglial lineage throughout the brain.

A 2-year prospective cohort study of cardiac resuscitation in a major Canadian hospital

OBJECTIVES

To determine the outcome of cardiopulmonary resuscitation (CPR) for in-hospital cardiac arrest and to identify risk factors associated with survival to the time of hospital discharge.

DESIGN

A 2-year prospective cohort study.

SETTING

Foothills Medical Centre, a 700-bed tertiary, academic and regional referral centre for Calgary and southern Alberta.

PATIENTS

Adult inpatients, excluding those who had cardiac arrest in the Emergency Department or operating room.

INTERVENTION

Cardiac resuscitation.

MAIN OUTCOME MEASURES

Spontaneous return of the pulse with a minimum systolic blood pressure of 80 mm Hg and survival defined as survival to the time of hospital discharge.

RESULTS

In 334 patients there were 390 cardiac arrests, of which 200 were primary cardiac arrests and 39 cardiac arrests that occurred while the resuscitation team was in attendance. Of 239 resuscitated patients, 51 (21.3%) survived. Fifteen variables were identified as being associated with survival. This association could be explained, through multivariate analysis, by the effect of the following 3 variables (odds ratio [OR], 95% confidence interval [CI]): initial observed rhythm other than pulseless electrical activity or asystole (OR 17.34, 95% CI 8.2 to 36.8); a patient who was ambulatory and able to provide self-care (OR 3.8, 95% CI 1.9 to 7.5); and a spontaneous return of circulation with resuscitation in less than 20 minutes (OR 12.9, 95% CI 4.8 to 20.7).

CONCLUSIONS

Survival to hospital discharge after cardiac arrest remains static. Initial cardiac rhythm and duration of resuscitation before spontaneous return of circulation were the most important risk factors for survival. These factors and the patient's functional status are relevant when discussing cardiac resuscitation with patients or when considering whether to discontinue resuscitation efforts.

Increased intestinal permeability is associated with the development of multiple organ dysfunction syndrome in critically ill ICU patients

We conducted a prospective, observational cohort study designed to compare intestinal permeability (IP) and development of multiple organ dysfunction syndrome (MODS) in a subset of critically ill patients in an intensive care unit (ICU). All patients with an expected ICU stay of 72 h or more were entered into the study, and IP was determined on a daily basis whenever possible from the urinary fractional excretion of orally administered lactulose and mannitol (LMR). Forty-seven consecutive patients were studied, and 28 developed MODS either at the time of admission or during their ICU course. These patients, as a group, had significantly worse IP at admission than did a non-MODS cohort (LnLMR: -2.10 +/- 1.10 versus -3.26 +/- 0.83). Those patients who developed MODS following admission also had a significantly greater admission IP than did the non-MODS group (-2.51 +/- 0.85). Differences in IP between cohorts could not be explained by differences in the incidence of systemic inflammatory response syndrome (SIRS)/sepsis or shock. With multivariate regression analysis, the only parameter present on admission that was predictive of subsequent MODS was IP. Differences in IP and the severity of organ dysfunction were also present (MODS severity mild: -3.01 +/- 0.72; moderate: -1.97 +/- 0.69; and severe: -1.12 +/- 0.96). Patients who developed MODS had a persistently abnormal IP during their ICU stay, and a significantly delayed improvement in their IP compared with the non-MODS cohort. We conclude that the development of MODS is associated with an abnormal and severe derangement of IP that is detectable prior to the onset of the syndrome. This observation lends credence to the premise that gastrointestinal (GI) dysfunction may be causally associated with the development of MODS in the critically ill patient.