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Three Part Question

In [children after trauma] does [critical illness] increase [the risk and incidence of venous thromboembolism]?

Clinical Scenario

A 12 year old female post motor vehicle collision is admitted to the pediatric ICU with a grade 3 liver laceration, pelvic bone fractures, and a humerus fracture. She has a central line that was started for treatment of hypotension. Your institution typically does not provide deep vein thrombosis (DVT) prophylaxis in children, but you wonder what the incidence and risk factors of venous thromboembolism (VTE) are in children who are critically ill after trauma.

Search Strategy

Medline 1950-August 15, 2011 using Ovid interface, Cochrane Library Clinical Queries, PubMed
[(exp venous thromboembolism) AND (children) AND (trauma)] [(exp pulmonary embolism) AND (pediatric trauma)] LIMIT to human AND English AND All child: 0-18 years.

Search Outcome

75 papers were identified, five were relevant to the clinical question.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
McBride et al, 1994 United States	28,692 patients from the National Pediatric Trauma Registry with a mean age of 9 years and a mean Injury Severity Score (ISS) of 11.	Retrospective review of a multi-institutional data base.	Six patients were found to have DVT and two patients were found to have a pulmonary embolus (PE), one of which died as a result.	The overall incidence of VTE was 0.03%. Both PE's occurred in patients with spinal cord injuries and paraplegia.	This is a retrospective review of a large database of children at 61 participating pediatric trauma centers. Although DVT was a reportable complication for the database, no routine evaluation was done to detect DVT or PE.
Vavilala et al, 2002 United States	58,716 pediatric patients aged less than 16 years were identified from 19 state discharge databases from 1997 or 1998 and from the American Hospital Association Annual Survey (1998).	Retrospective review of pediatric patients across 19 states with a diagnosis of trauma.	45 patients had a discharge diagosis of VTE for an incidence of 0.08%.	Risk factors for VTE include older age, higher ISS, major vascular injury, central line, and craniotomy.	This is a retrospective study based on admission diagnoses and ICD-9 discharge diagnoses. The diagnosis of VTE does not separate DVT from PE.
Truitt et al, September 2005 United States	3637 pediatric trauma patients admitted to a single institution over 7 years.	Case-control study of pediatric trauma patients with DVT/PE.	Three patients developed DVT/PE with an overall incidence of 0.08%.	No routine prophylaxis for DVT/PE is recommended, but it should be considered for age > 8, GCS ≤ 8, or ISS >25.	The study was retrospective, limiting its scope.
Cyr et al, 2006 Canada	Children < 18 years who were severely injured and were admitted to a pediatric intensive care unit (PICU) or had a length of stay ≥ 72 hours with a discharge diagnosis of VTE.	This was a retrospective review of a cohort of pediatric trauma patients. ICD-9 codes were used to identify the patients and a multivariate analysis was used.	VTE was diagnosed in 11 of 3291 (0.33%) study patients.	ISS, increasing age, chest injury, spine injury, and central venous catheters were associated with VTE.	This was a retrospective review with a small sample. Injured non-PICU patients discharged prior to 72 hours were excluded.
Hanson et al, 2010 United States	144 patients admitted to a PICU after trauma. Nine patients were identified with VTE and three patients were selected as controls for each patient with VTE.	Single institution prospective nested case-control study.	9 injured children (6.2%) admitted to the PICU developed VTE. This is an incidence of 6.2%.	Most injured children who developed VTE have multiple risk factors including poor perfusion, immobility, and a central venous line.	The study was limited to patients admitted the PICU at one center during a 15 month period leading to a small sample size.

Comment(s)

To date, studies evaluating for venous thromboembolism in paediatric trauma patients who are critically ill are primarily retrospective with small sample sizes. A single nested case–control study was identified, but this also has a small sample size. Incidences of venous thromboembolism in the evaluated studies range from 0.03% when all paediatric trauma patients are included, up to 6.2% when looking only at injured patients requiring paediatric intensive care unit admission. Risk factors across the studies include older age, Injury Severity Score >25, GCS ≤8, spinal cord injuries, presence of a central line, major vascular injuries, and undergoing a craniotomy. Routine prophylaxis is not recommended for paediatric trauma patients although it may be considered with the presence of the identified risk factors. No definite guidelines for prophylaxis exist.

Editor Comment

DVT, deep venin thrombosis; ISS, Injury Severity Score; PE, pulmonary embolus; PICU, paediatric intensive care unit; VTE, venous thromboembolism.

Clinical Bottom Line

In critically ill pediatric trauma patients, the incidence of VTE is small and in some studies extremely rare. Risk factors for VTE include increased age, high ISS, central venous line, and severe injuries to the head, spinal cord, and major vessels.

References

1. McBride W, Gadowski G, Keller M, et al. Pulmonary Embolism In Pediatric Trauma Patients. J Trauma 1994;37:913-915
2. Vavilala M, Nathens A, Jurkovich G et al. Risk Factors for Venous Thromboembolism in Pediatric Trauma. J Trauma. 2002;52:922-927.
3. Truitt A, Sorrells D, Halvorson E, et al. Pulmonary Embolism: Which Pediatric Trauma Patients Are At Risk? J Ped Surg 2005;40:124-127
4. Cyr C, Michon B, Pettersen G, et al. Venous Thromboembolism After Severe Injury in Children Acta Haematologica 2006;115:198-200
5. Hanson S, Punzalan R, Greenup R et al. Incidence and Risk Factors for Venous Thromboembolism in Critically Ill Children After Trauma J Trauma 2010;68:52-56