Consider gentle irrigation of the wound until the fluid

returning is clear. Pack the wound with enough iodoform

gauze to keep the sides of the abscess from touching. This

will allow for further drainage. Cover the wound with

gauze.

When treating a Bartholin gland abscess, a small catheter (Word catheter) is placed in the opening instead of

iodoform. The catheter should remain in place for several

weeks to allow for the development of a fistula for continued drainage.

I NCISION AND DRAINAGE

The patient is instructed to follow up in 48 hours to

have the packing removed. If pus is no longer present and

symptoms are resolving, the wound is allowed to heal by

secondary intention.

COMPLICATIONS

Scarring from the abscess and incision will occur. Numbness

from cutaneous nerve injury may occur. Seeding of the

blood with bacteria may transiently occur.

SUGGESTED READING

Fitch MT, Manthey DE, McGinnis HD, et al. Abscess incision

and drainage. N Eng! J Med 2007;357:e20.

Hankin A, Everett WW. Are antibiotics necessary after incision and

drainage of a cutaneous abscess? Ann Emerg Med. 2007;50:

49-5 1.

Kelly EW, Magilner D. Soft tissue infections. In: Tintinalli JE,

Stapczynski JS, Ma OJ, Cline DM, Cydulka RK, Meckler GD.

Tintinalli's Emergency Medicine: A Comprehensive Study Guide.

7th ed. New York, NY: McGraw-Hill, 20 11: Pages 1014-1024.

Arterial B lood Gas

Brian C. Kitamura, MD

John Sarka, MD

Key Points

• Arterial puncture for blood gas ana lysis is a common

procedure performed in the emergency department

(ED).

• Blood obtained from the radial artery can be used

to quickly provide qua ntitative information on the

INDICATIONS

The primary indication for obtaining an arterial blood

sample is for the assessment of the partial pressures of

oxygen and carbon dioxide and accurate assessment of

arterial pH. Secondarily, arterial blood can be analyzed

for carboxyhemoglobin, methemoglobin, and basic elec ­

trolytes depending on the capabilities of the laboratory.

Under certain circumstances it may be necessary to

obtain a sample of arterial blood for other routine laboratory tests, such as in patients who are obese or have a

history of intravenous drug abuse, in whom the radial

artery is palpable, but venous access is difficult or may be

delayed.

CONTRAINDICATIONS

There are few absolute contraindications for arterial puncture for blood gas analysis. Trauma, infection, or abnormalities of the overlying skin such as a burn are

contraindications because of concern for infection or further damage to the vascular structures. Patients with

known coagulopathies, taking anticoagulants, or who may

require thrombolytic agents should be approached with

caution because of the increased risk of bleeding, hema ­