A 48 y.o. male is shot in the posterior calf with a water cannon. He was seen and discharged on bactrim and now returns with worsening pain one day later.

What do you notice and what should be done?

Our patient was injected with water under high pressure. The air in the leg was a result of that high pressure injection. The extent of damage depends on a number of factors, but the most important determinant the chemical composition of the injected material. Paint and paint thinner cause a significant inflammatory response and result in a high percentage of amputations.  Grease injuries case a small inflammatory response but are associated with scarring and loss of function when they occur in the hand. The amount of material injected determines contributes to the compartment pressure, so as more material is injected, the possibility of compartment syndrome increases. 

Swelling of the L calf one day after injury.

Initially, a high pressure injury may not look bad.  There can be either an innocuous entrance or no visible break in the skin.  Several hours later, the involved area may become extremely painful because of vascular compromise and tissue necrosis.  Our patient had been seen in an ED the day prior to coming here and was given Bactrim and told to elevate the leg.  He continued to have pain, and this is what brought him to our ED.  The leg was quite swollen when he arrived.  He was given antibiotics, managed without surgery, and discharged in three days.

More serious injury occurs with paint guns.

Another case of a high pressure water hose injury was seen at Children’s Hospital. A four year old tried to drink out of a power washer hose and injected water into the R tonsillar pillar.  He had significant air in the mediastinum and neck but did not require surgery. 

Injection of the R tonsillar pillar.

FOR PHYSICS NERDS

Medium duty power washers range in pressure from 1,300-2,000 psi and are used for cleaning driveways. Heavy duty washers have 2,700-4,000 psi and can strip paint. Paint guns can generate 3,600 psi, and a garden hose has 40 psi of pressure.  

Duplechain JK, Espinola T, Miller RH. Water spout injection into the neck. Arch Otolaryngol Head Neck Surg. 1993;119:237-38.

Sampson C,  High-pressure water injection injury. Int J Emerg Med 2008. Jun 1 (2) 151-154.

Verhoeven N, Hiemer R. High-pressure injection injury of the hand: an often underestimated trauma: case report with study of the literature.  Strategies Trauma Limb Reconstr 2008 Apr.3(!):27-33.ps