ALTE

Agosto 2010

HOSPITAL MEDICINE

Risk Factors for Extreme Events in Infants Hospitalized for ALTE

Source: Al-Kindy HA, Gelinas JF, Hatzakis G, et al. Risk factors for extreme events in infants hospitalized for apparent life-threating events. J Pediatr. 2009;154(3):332-337; doi:10.1016/j.jpeds.2008.08.051

Researchers from the Montreal Children’s Hospital performed a retrospective cohort study to identify risk factors for severe cardiorespiratory events in infants hospitalized due to apparent life-threatening events (ALTE). The study group included patients who were examined in the emergency department between April 1996 and March 2006 for ALTE and admitted. Patients were excluded if they had pre-existing respiratory control problems, airway anomalies, cyanotic heart disease, arrhythmias, tracheostomy, or prior cardiorespiratory monitoring.

Severe or extreme events were defined as central apnea for >30 seconds, bradycardia (<60 bpm for infants under 44 weeks postconceptional age [PCA] or <50 bpm for infants 44 or more weeks PCA) for >10 seconds, and desaturation to <80% for >10 seconds. The study population consisted of 625 infants with a median age of 43 days, 21% of whom were born prematurely. Of these, 338 were subsequently monitored with memory capable cardiorespiratory and/or Sp02 monitors.

Of the 338 infants with documented monitoring, 46 (13.6%) experienced extreme events. All but seven of these events occurred during the first 24 hours of hospitalization although 41 of the 46 infants (89%) did not appear sick at the time of admission. Twenty-five of the patients with extreme events were eventually admitted to the pediatric intensive care unit. Desaturation was the most common extreme event (43/46 infants, 94%) and was often preceded by central apnea. Twenty-seven infants had central apneas >30 seconds. If Sp02 monitoring had been omitted, 14 infants with extreme events would have been missed.

Among infants on a recording monitor, risk factors for extreme events during hospitalization were prematurity (RR 6.3; 95% CI, 3.6-11.0), PCA under 43 weeks (RR 5.2; 95% CI, 2.6-10.3), and symptoms of upper respiratory tract infection (URTI) (RR 11.2; 95% CI, 6.7-18.9). Extreme events were recorded in the hospital only in infants younger than 48 weeks PCA.

Eighty-eight infants were discharged with home monitoring and seven (8.0%) had extreme events at home. All of these infants had extreme events in the hospital as well. Of these, four infants had recurrent events with an URTI, two were diagnosed with pertussis, and one hypotonic infant was diagnosed with nemaline rod myopathy.

The authors recommend that infants younger than 48 weeks PCA with an ALTE be hospitalized and monitored for the first 24 hours with a pulse oximeter or cardiorespiratory monitor, preferably one with memory capacity.

Commentary by

Brian Pate, MD, FAAP, Pediatric Hospital Medicine, Children’s Mercy Hospital, Kansas City, MO

Dr. Pate has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.

The management of ALTE presents unique challenges to parents and clinicians across the continuum of health care. At the point of care, the parent’s extreme concern for an infant is translated to a physician’s responsibility to provide a clinical evaluation, consider probable diagnoses, and if possible, prevent a recurrence. For the physician, performing these responsibilities in a consistent, evidence-based, and efficient manner is hampered by a subjective chief complaint in a frequently healthy-appearing infant.1

The management of infants with ALTE is often inefficient and inconsistent.2,3 Lack of a "positive" work-up or definitive diagnosis in a majority of cases generates a focus on predicting and/or preventing recurrence. In this context, studies such as this one have special value. Prior studies have demonstrated admission rates following an ALTE near 80%, while others suggest this rate could be as low as 14% if reliable high-risk criteria could be identified.4 Home monitoring might also be appropriately applied5 with better definition of risk factors.

Despite important limitations in study design, notably the possibility for selection bias and the inconsistent application of documented monitoring, this study is helpful. The results confirm prior studies identifying prematurity and young age as risk factors for ALTE.6 The study also highlights the importance of Sp02 monitoring in addition to cardiorespiratory monitoring and identifies concurrent or subsequent URTI as a risk factor for an extreme event. Recognition of these risk factors has the potential to inform and improve clinical decision-making at admission and discharge.

References

Key words: risk factors, severe events, apparent life-threatening events