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S H Thomas

Publications and source records attributed to S H Thomas.

117 records · Page 7Linked to original sources

Can correct closed-chest compressions be performed during prehospital transport?

INTRODUCTION: The resuscitation rate from out-of-hospital cardiac arrest is low. There are many factors to be considered as contributing to this phenomenon. One factor not previously considered is the impact of a moving ambulance environment on the ability to perform closed-chest compressions. HYPOTHESIS: Proper closed-chest compressions can be performed in a moving ambulance. METHODS: A cardiopulmonary resuscitation (CPR) training mannequin with an attached skill meter (Skillmeter ResusciAnnie, Laerdal, Armonk, N.Y., USA) that measures each chest compression for proper depth and hand placement was used. Ten emergency medical technician-basic (EMT-B) certified prehospital providers were assigned into one of five teams. Each team performed a total of four sessions of five minutes of continuous closed-chest compressions on the mannequin. Two sessions were done by each team: one in the control environment with the mannequin placed on the floor, and the other in the experimental environment with the mannequin placed in the back of a moving ambulance. The ambulance was operated without warning lights and siren, and all traffic rules were obeyed. The percentage of correct closed-chest compressions was recorded for each session, and the mean values were compared using Student's t-test with alpha set at 0.01 for statistical significance. RESULTS: Ten sessions of compressions were done in both environments. The mean percentage of correct compressions was 77.6 +/- 15.6 for the control group and 45.6 +/- 18.3 for the ambulance group (p = 0.0005). CONCLUSION: A moving ambulance environment appears to impair the ability to perform closed-chest compressions.

Ambulances↗

Does the ambulance environment adversely affect the ability to perform oral endotracheal intubation?

OBJECTIVE: Oral endotracheal intubation (ETI) is the preferred method of controlling the airway in critically ill or injured patients. It was postulated that time could be saved if intubation was performed in the ambulance en route to the hospital. This study was designed to determine whether the ambulance environment adversely affected the ability of emergency medical technicians at the advanced-intermediate level (EMT-AI) to perform oral ETI. HYPOTHESIS: The restrictive environment of a moving ambulance would affect adversely the ability of EMT-AIs to perform ETI compared with a controlled setting. This would result in a significant increase in the time necessary to perform ETI in the ambulance compared with a controlled setting not complicated by restrictive space and motion. METHODS: Twenty on-duty EMT-AIs were recruited to volunteer for this prospective, nonrandomized, nonblinded trial. All participants performed three consecutive oral ETIs on an airway mannequin in two settings: 1) in the back of a moving ambulance; and 2) on a table in the rescue squad station. Of the participants, 10 performed the intubations in the ambulance first; the remainder performed the intubations at the station first. Time for intubation with the mannequin was recorded by stopwatch. The mean times for intubation in both settings were compared by Student's t-test (p < 0.05). RESULTS: All intubation attempts were successful. The mean time for intubation in the station was 13.0 +/- 3.4 seconds. The mean time in the ambulance setting was 13.2 +/- 5.3 seconds. There was no significant difference between the intubation times in the two settings (p = 0.88). CONCLUSION: The environment of a moving ambulance does not appear to hinder the ability of EMT-AIs to perform oral ETI in a laboratory setting with a mannequin model.

Ambulances↗

Helicopter emergency medical services roles in disaster operations.

Rotor-wing aircraft have previously proven utility in disaster operations, but recent expert reviewers have identified areas of potential improvement in integration of helicopter emergency medical services (HEMS) resources into disaster planning and management. This paper discusses salient points regarding helicopter operations in disaster management, using prior reports regarding rotor-wing aircraft utilization as a basis upon which to provide a concise review of HEMS operations in disasters.

Air Ambulances↗

Potential time savings by prehospital administration of activated charcoal.

OBJECTIVE: Activated charcoal (AC) has been proven useful in many toxic ingestions. Theoretically, administration of AC in the prehospital environment could save valuable time in the treatment of patients who have sustained potentially toxic oral ingestions. The purpose of this study was to determine the frequency of prehospital AC administration and to identify time savings that could potentially result from field AC administration. METHODS: Adult patients with a chief complaint of toxic ingestion who had complete emergency medical services (EMS) and emergency department (ED) records and no medical treatment (gastric emptying, AC administration) prior to EMS arrival were eligible for inclusion. Data obtained from EMS and ED records included time of EMS departure from the scene, time of EMS arrival at the ED, and time of administration of AC in the ED. Since most EMS agencies in this system do not insert gastric tubes, patients requiring gastric tube placement for administration of AC were excluded. RESULTS: Twenty-nine of 117 (24.8%) adult patients received oral AC with no other intervention. None of the 117 patients received AC in the prehospital setting. The EMS transport time for these patients ranged from 5 to 43 minutes (mean 16.2 +/- 9.7 minutes). The delay from ED arrival to AC administration ranged from 5 to 94 minutes (mean 48.8 +/- 24.1 minutes), and was more than 60 minutes for 14 (48.2%) of the patients. The total time interval from scene departure to ED AC administration ranged from 17 to 111 minutes (mean 65.0 +/- 25.9 minutes). CONCLUSIONS: In a selected subset of patients who tolerate oral AC, prehospital administration of AC could result in earlier and potentially more efficacious AC therapy. Prospective study of the benefits and feasibility of prehospital AC administration is indicated.

Antidotes↗

Air vs ground transport and outcome in trauma patients requiring urgent operative interventions.

OBJECTIVE: To study trauma patients requiring urgent operative interventions to determine whether transport mode was associated with outcome difference. METHODS: Eligible patients were injured adults and children who presented over a 57-month period to the emergency department (ED) at the study hospital (annual ED census 36,000) after air or ground transport from trauma scenes or referring hospitals. Patients included were those whose ED lengths of stay were <60 minutes prior to transfer to an operating room. Data collected included injury severity score (ISS), ED and hospital lengths of stay, and mortality. Continuous data, which were not distributed normally, were analyzed using Wilcoxon nonparametric analysis. Categorical variables were analyzed using chi-square testing. Multivariate logistic regression was used to account for confounding variables and isolate the effects of transport mode on mortality. Alpha for all tests was set at 0.05. RESULTS: 272 patients were eligible for study; 168 air medical and 104 ground transports. No between-group differences were found for ED length of stay, ISS, or mortality. A significantly longer hospital stay was found for air-transported patients. Subgroup analysis of patients with penetrating trauma and ISS of > or =25 revealed mortalities of 28% and 45% for air- and ground-transported patients, respectively; this difference was not statistically significant (p = 0.24), but the study had a power of only 22% to detect a difference at this magnitude. CONCLUSION: This study failed to identify, but had insufficient power to rule out, outcome benefit to air medical transport in a subset of trauma patients requiring urgent operative interventions.

Adolescent↗

Prehospital and emergency department analgesia for air-transported patients with fractures.

OBJECTIVE: To evaluate prehospital and receiving emergency department (ED) analgesia administration in air-transported patients with isolated fractures. METHODS: The study was a retrospective descriptive analysis of flight and hospital records. Study patients were consecutive adults (not pharmacologically paralyzed) with fractures undergoing scene or interfacility helicopter transport during 1994-1996. The study aeromedical program uses two helicopters staffed by a nurse/paramedic flight crew providing protocol-guided care. The receiving ED was in an urban academic Level I trauma center (annual census 65,000). Primary data collected were timing and amount of prehospital and ED analgesia. Analysis was mainly descriptive, with chi-square and nonparametric methods used to compare patients who did and did not receive intratransport fentanyl. RESULTS: 130 patients with isolated fractures underwent air transport during the study period 1994-1996. Of these, 98 (75.4%) received intratransport fentanyl; 20 of 98 (20.4%) received no analgesia in the receiving ED. Patients who did receive repeat analgesia in the receiving ED (n = 78, 79.6% of those receiving prehospital fentanyl) had a median interval of 42.5 minutes (interquartile range 25-100) between ED arrival and analgesia administration; only 62.8% of these patients received their ED analgesia within 60 minutes of arrival. CONCLUSIONS: Some patients receiving intratransport fentanyl received no ED analgesia, and those who did receive ED analgesia often had administration delays surpassing the clinical half-life of intratransport-administered fentanyl. Further study should investigate whether setting-specific analgesia practice differences reflect true differences in analgesia needs, overmedication by prehospital providers, or undermedication by ED staff.

Adult↗

Flight crew airway management in four settings: a six-year review.

OBJECTIVE: To analyze flight crew airway management in four different settings (in flight, at trauma scenes, in ambulance, and in referring hospitals) and in two different aircraft used by the same helicopter EMS (HEMS) service. The null hypothesis was that there was no association between practice setting, or aircraft, and airway practices or success rate. METHODS: This retrospective study analyzed all patients in whom advanced airway management was attempted by the HEMS service during the study period October 1991 through October 1997. Data used were from flight records of Boston MedFlight Critical Care Transport Service, which uses a nurse/paramedic crew and had a paralytic-assisted intubation protocol in place. Data were analyzed with chi-square and Fisher's exact testing, risk ratio analysis, and logistic regression. RESULTS: Advanced airway management was attempted in 722 patients, with an airway placed in 705 (97.8%). Intubation success was unrelated to site of airway management (p = 0.14), but patients were more likely to have intubation attempted prior to flight (as opposed to in flight) if the crew were in the AS365N2 Dauphin as compared with the BK-117 (p<0.0001). In addition, patients were 0.77 times as likely (95% confidence interval, 0.68-0.88) to receive paralytic-facilitated intubation if airway management occurred in the hospital setting as compared with other sites. CONCLUSIONS: While HEMS crew airway management success rates are equally high in all practice settings, airway management decision making and practice appear to be significantly influenced by practice setting and aircraft type. These data support contentions that nonphysician HEMS crews can effectively manage airways in a variety of circumstances.

Adult↗