Antibiotics & Patient Monitoring

Study Notes

An ideal antibiotic would kill 100% of bacteria, only target intended bacteria, be simple to administer, and have no side effects.
In reality, antibiotics can lead to antibiotic resistance, harm local flora, and have side effects.

Immediate monitoring is crucial within the first hour for anaphylaxis, which can present with rash, itching, dyspnea, and edema.
Monitor for anaphylaxis every fifteen minutes. Stop the infusion and administer an antihistamine.
Delayed monitoring is necessary for Stevens-Johnson Syndrome (SJS), also known as toxic epidermal necrosis, which can be fatal.
Pseudomembranous colitis (aka C.diff or CDAD) is a serious complication commonly associated with antibiotics. Monitor for any signs of this.

Major classes of beta-lactams include penicillins, cephalosporins, carbapenems, and monobactams.
Beta-lactams inhibit bacterial cell wall synthesis by targeting the beta-lactam ring.
Allergies are a serious concern with beta-lactams, particularly if a patient has a history of reaction to one.
Cross-allergenicity is a consideration when choosing a beta-lactam, as allergy to one may indicate allergy to another.
Administer cephalosporins 60 minutes prior to the first surgical incision for surgical prophylaxis.
Ceftriaxone is notable for its ability to be administered via deep IM injection, though this is often painful.

Prototype: Ampicillin
Typically strong against gram-positive bacteria, but weaker against gram-negative.

A combination drug consisting of a penicillin and a beta-lactamase inhibitor, which expands its spectrum of activity to include gram-negative bacteria.

Prototype: Cefazolin
Divided into five generations with increasing spectrum of activity and resistance to breakdown by bacterial enzymes.

Prototype: Aztreonam
Considered relatively safe in patients with penicillin allergies.
Limited cross-allergenicity, making it a valuable option for penicillin-allergic patients.

Prototype: Gentamicin
Destroy bacterial ribosomes, disrupting protein synthesis.
Primarily effective against gram-negative bacteria.
Black Box Warnings for ototoxicity and nephrotoxicity.
Monitor serum peak and trough levels to ensure therapeutic efficacy and minimize toxicity.

Prototype: Ciprofloxacin
Interfere with bacterial DNA production, disrupting cell replication.
Broad spectrum, with activity against gram-negative and some gram-positive bacteria.
Used as a first-line treatment for Bacillus anthracis (anthrax).
Black Box Warnings for tendinitis and tendon rupture, particularly in patients with myasthenia gravis.
Can interact with iron, multivitamins, calcium, and dairy products.
Avoid prolonged direct sunlight exposure.

Prototype: Tetracycline Hydrochloride
Inhibit microbial protein synthesis.
Broad spectrum, including activity against Mycoplasma, Chlamydia, and Rickettsia; important for treating Lyme disease.
Consider renal function when dosing.
Can reduce contraceptive efficacy.
Teeth discoloration risk in children.