Timing of suture removal

What it is

Suture removal timing is set by the region of the body, and the list runs from the fastest to the slowest: face 3-5 days, neck 5-7 days, scalp 7-10 days, chest and abdomen 7-10 days, back 10-14 days, arms and legs 10-14 days, hands and feet 10-14 days, and joints 10-14 days.

How it is treated

Most sutures can be removed 7 days after placement. Sutures on the face should be removed in 3 to 5 days to prevent unsightly hatch markings, and leaving facial sutures in for 7 to 10 days leads to a poorer outcome. Sutures in areas of high tension, such as arms, legs, hands, and feet, require approximately 10 days; so for a large laceration in a high-tension area, removing the sutures 10 days after placement is the best management, and asking the patient to return in 3 days would be too soon. Leaving sutures in longer improves wound strength at the expense of the cosmetic outcome.

The choice of suture material is made on tissue type, tissue tension, and whether or not the sutures will require removal. Oral mucosa is rapidly healing and under moderate tension, and because the inner lip mucosa does not require a cosmetic result, absorbable sutures are used there: a 5-0 absorbable chromic gut gives tensile strength that matches that of the oral mucosa. The material is chosen for the site. Staples do not give the desired cosmesis for a facial wound repair and are more appropriate for a scalp laceration; Steri-Strips can be used in very small skin openings with minimal tension but will not provide the tensile strength required for a wound under more tension; and tissue adhesive is inadequate for a laceration that crosses the hairline. Shaving the surrounding hair increases the risk of infection and is not recommended, and eyebrows should not be shaved because of the high likelihood that they will not regrow. A 1-0 chromic gut is unnecessarily large for oral mucosa and would leave an uncomfortably large knot mass; absorbable monofilament sutures give more tensile strength than is needed there and are preferred for closure of deep structures such as fascia; and nylon is not the best choice for oral cavity repairs because it would require the patient to return for removal. For anesthesia, a lidocaine digital block at the base of the finger blocks the digital nerves: the needle is inserted into the web space on either side and anesthesia is deposited anteriorly and posteriorly, then repeated on the opposite side of the affected digit. Epinephrine is contraindicated in areas of end organ circulation, that is the tip of the nose, the glans penis, the scrotum, the ears, the nose and the fingers. The dose has a limit of its own: without epinephrine the max dose of lidocaine is 4.5 mg/kg, and the strength is read off the label by multiplying the per cent by 10 to get mg/mL, so 1% lidocaine = 10 mg/mL. Max volume in mL = [4.5 x weight in kg] divided by [concentration in mg/mL]. Worked on the page for a 100 kg patient given lidocaine 4%, that is 40 mg/mL: max dose = 4.5 x 100 = 450 mg, and max volume = 450 divided by 40 = 11.25 mL. Irrigating a wound with anesthetic does not provide adequate anesthesia, and local infiltration, although adequate, may interfere with good wound approximation and lead to a poor cosmetic result. A laceration crossing the vermilion border, the demarcation of the lip mucosa and facial skin, is repaired to approximate that border with less than 2 mm of displacement; a nerve block is required because local anesthesia would distort the tissue anatomy, and the first stitch focuses on approximating the border prior to closing the other aspects of the wound. Puncture wounds cannot be cleaned adequately because of their depth, so delayed primary closure decreases the risk of abscess formation and wound infection; puncture wounds, small lacerations, and hand and foot wounds carry higher risks of infection and are best managed that way. Approximately 5% of dog bites and 80% of cat bites become infected, copious irrigation is crucial in preventing wound infections, and most bite wounds can be repaired with primary closure. Pasteurella is the most common organism in cat bites, while dog bites are often polymicrobial and include aerobes and anaerobes. Antibiotics should be considered in all high infection risk patients, that is the elderly, diabetics, immunocompromised patients, puncture wounds, and wounds of the hands and feet; the most commonly used antibiotic for dog and cat bites is amoxicillin/clavulanate, with clindamycin plus a fluoroquinolone for dog bites in penicillin allergic patients and doxycycline for cat bites in penicillin allergic patients. A foreign body with the potential to cause infection and an inflammatory response requires immediate removal, and the examples given are thorns, splinters, spines, teeth and soil-covered objects; if it cannot be removed by the emergency physician the appropriate specialist should be consulted. Organic materials are radiolucent, so radiographs will not assist in locating them and thorough direct visual inspection is necessary. Wounds with stagnant freshwater exposure are at high risk of infection with gram positive, Pseudomonas and Aeromonas species and require empiric antibiotic coverage.