Kids In-Hospital Arrests; Delays in AMI Treatment; Prehospital ETI/PPV
Kids' In-Hospital Arrests, Outcomes
Nadkarni VM, Larkin GL, Peberdy MA, et al. First documented rhythm and clinical outcome from in-hospital cardiac arrest among children and adults. JAMA 295(1):96-8, Jan. 4, 2006.
Abstract: Objective-To test the hypothesis that children have relatively fewer in-hospital cardiac arrests associated with VF or pulseless VT compared with adults and, therefore, worse survival outcomes. Design, setting and patients-A prospective observational study from a multicenter registry of cardiac arrests in 253 U.S. and Canadian hospitals between January 1, 2000, and March 30, 2004. A total of 36,902 adults (> or = 18 years) and 880 children (< 18 years) with pulseless cardiac arrests requiring chest compressions, defibrillation or both were assessed. Cardiac arrests occurring in the delivery department, neonatal intensive care unit and out-of-hospital setting were excluded. Outcome measure-Survival to hospital discharge.
Results-The rate of survival to hospital discharge was higher in children than adults (236/880, 27%, vs. 6,485/36,902, 18%). Of these survivors, 65% (154/236) of children and 73% (4,737/6,485) of adults had good neurological outcomes. The prevalence of VF or pulseless VT as the first documented pulseless rhythm was 14% (120/880) in children and 23% (8,361/36,902) in adults (OR 0.54; 95% CI, 0.44-0.65; p < .001). The prevalence of asystole was 40% (350) in children and 35% (13,024) in adults (OR 1.20; 95% CI, 1.10-1.40; p = .006), whereas the prevalence of PEA was 24% (213) in children and 32% (11,963) in adults (OR 0.67; 95% CI, 0.57-0.78; p < .001). After adjustment for differences in preexisting conditions, interventions in place at time of arrest, witnessed and/or monitored status, time to defibrillation of VF or pulseless VT, intensive care unit location of arrest and duration of cardiopulmonary resuscitation, only first documented pulseless arrest rhythms remained significantly associated with differential survival to discharge (135/563, 24%, in children vs. 2,719/24,987, 11% in adults with asystole and PEA). Conclusions-The first documented pulseless arrest rhythm was typically asystole or PEA in both children and adults. Because of better survival after asystole and PEA, children had better outcomes than adults despite fewer cardiac arrests due to VF or pulseless VT.
Comment: The 2005 American Heart Association guidelines for CPR and emergency cardiovascular care restate the 2003 recommendation to use an AED on children ages 1-8. Prior to 2003, this had not been recommended, since the evidence was that ventricular fibrillation was almost never seen in children. Here, 14% of children had VF or pulseless VT as their first documented rhythm, and other studies have presented similar results. Although there are limitations in generalizing these results to EMS (these were hospitalized patients and included patients aged less than 1 and 8-18), the data suggests that ventricular fibrillation is not a rare rhythm. Those in charge of AED programs should consider this as they select and equip AEDs and design treatment protocols.
Delays in AMI Treatment
McGinn AP, Rosamond WD, Goff DC, Jr., et al. Trends in prehospital delay time and use of emergency medical services for acute myocardial infarction: Experience in four U.S. communities from 1987-2000. Am Heart J 150(3):392-400, Sept. 2005.
Abstract: Background-Prolonged delay in seeking care for acute myocardial infarction (AMI) is associated with decreased use of time-dependent treatments and increased mortality and morbidity. Methods-Times from symptom onset to arrival at hospital and emergency medical service use were abstracted from the medical records of 18,928 patients hospitalized for AMI and captured in the community surveillance component of the Atherosclerosis Risk in Communities (ARIC) study from 1987-2000. A cutoff point of four hours was used to assess clinically relevant delay time recommendations for treatment with current therapies. Results-In 2000, the overall proportion of persons with delays from symptom onset to hospital arrival of greater than or equal to four hours was 49.5%. Blacks and women were consistently delayed longer than whites and men. Between 1987 and 2000, there was no statistically significant change in the proportion of patients delaying greater than or equal to four hours (relative change: +0.6% in men, -7.4% in women, -2.3% in whites, -8.9% in blacks, -7.9% in persons with diabetes and -0.8% in persons without diabetes); however, there is a noticeable narrowing of gaps between sex, race and diabetes status over the study period. The percentage of those who used emergency medical services increased significantly over the study period (1987: 37.1%, 2000: 44.5%; p < or = .0001). Conclusions-Many patients continue to experience prolonged delays from onset of symptoms to hospital arrival. Delay times for hospitalized AMIs changed little in the ARIC communities from 1987-2000. New public-health strategies should be developed to facilitate rapid access to acute care for AMI.
Comment: The Atherosclerosis Risk in Communities (ARIC) study from North Carolina began in 1987 and will continue until at least 2007. With all of the public education on the use of 9-1-1 and the overall increase in the use of emergency medical services, often for less-serious medical conditions, it is disappointing to see that more than half of all patients with acute myocardial infarctions still do not call for ambulances. Preventing death after AMI is, arguably, the reason why EMS systems were first started. In addition, half of all AMI patients still waited for hours or more before seeking medical care. This underscores the importance of continuing our public-education efforts.
Prehospital ETI/PPV, Hypotension and Survival
Shafi S, Gentilello L. Prehospital endotracheal intubation and positive pressure ventilation is associated with hypotension and decreased survival in hypovolemic trauma patients: An analysis of the National Trauma Data Bank. J Trauma 59(5):1,140-5, Nov. 2005.
Abstract: Methods-A national sample (from the National Trauma Data Bank, 1994-2002) was used to minimize effects of local paramedic training and experience. All patients with prehospital Glasgow Coma Scale scores less than 8 (i.e., most likely to warrant early ETI) and Injury Severity Scores greater than 16 (most likely to be hypovolemic) were included. Patients intubated in the field (n = 871) and the emergency department (n = 6,581) were compared. To determine whether prehospital ETI was an independent predictor of hypotension and mortality, logistic regression was used to control for potential confounders, including age, ISS, body region injured, AIS scores, prehospital IV fluids and other variables. Physiologic variables were not used, as they may be influenced by ETI and positive pressure ventilation, and were therefore considered outcomes, rather than predictors. Results-Groups were comparable in age, gender, anatomic distribution of injuries, likelihood of at least one severe injury (AIS > 3) and other variables, except for head injury (ED 83%, prehospital 71%; p < 0.001) and ISS (ED 33 +/- 0.2, prehospital 36 +/- 0.6; p < 0.001). Patients intubated in the field were more likely to be hypotensive upon arrival in the ED (SBP < or = 90 mmHg; ED 33%, prehospital 54%; p < 0.001), and had worse survival (ED 45%, prehospital 24%; p < 0.001). Even after controlling for potential confounders, prehospital ETI was still an independent predictor of hypotension upon arrival in the ED (OR 1.7; 95% CI, 1.46-2.09; p < 0.001) and decreased survival (OR 0.51; 95% CI, 0.43-0.62; p < 0.001). Conclusions-Prehospital endotracheal intubation in trauma patients is associated with hypotension and decreased survival. This may be mediated by the effect of positive pressure ventilation during hypovolemic states.
Comment: Traditional teaching holds that the first and most important step in the resuscitation of the trauma patient is to secure the airway. More recent reports have looked specifically at the practice of endotracheal intubation in the field and have concluded that it may be better to delay intubating the head-injured patient in the emergency department. This study suggests that intubation of hypovolemic trauma patients may increase the likelihood of hypotension and worsen outcomes. This will require further research, hopefully with prospective studies, and hopefully will eventually help us improve outcomes of these seriously injured multiple-trauma patients.
