Data will be collected on the type of tourniquet and circumstances of its use. Patients with penetrating extremity injury will have clinical and pre-clinical hospital data collected.

This is a performance improvement project that is a prospective observational cohort design with subgroup analyses. This project meets the criteria of research with its intent to publish. No data is generated and only existing data are used. No interventions are made and the comparisons will be with within subgroups in the cohort.

Aim 1. Describe the number of tourniquets which were appropriately used (wound required a tourniquet and tourniquet was placed properly) as assessed by treating physician

Aim 2 &3. Describe if limbs wounds with tourniquets were bleeding upon admission, resuscitation, and following tourniquet removal

Aim 4. Describe if mortality for the cohort of patients with tourniquets is different than the mortality predicted by various injury scoring systems

Aim 5. Compare patient outcomes between those in which a tourniquet was indicated but not used and those for whom a tourniquet was indicated and used

Aim 6. Determine if patients that received tourniquets for an extended time period exhibit any known tourniquet complications

Inclusion Criteria:

• penetrating extremity injury with tourniquet use

Exclusion Criteria:

• non penetrating extremity injury

Combat soldiers on whom tourniquet was applied.