Acute pelvic pain

Gynaecology

Emergency department

The first question

Is she pregnant, and could this be torsion?

01
Pregnancy test
Before anything else.
02
Stability
Ruptured ectopic and haemorrhagic cyst can bleed enough to shock.
03
Ultrasound
Transvaginal for the uterus and adnexa; Doppler for the ovary; free fluid.
04
Decide who needs theatre tonight
Torsion, ruptured ectopic, tubo-ovarian abscess that fails treatment, appendicitis.

Where it is

Each opens the structure on the 3D pelvis.

History that discriminates

Onset (sudden or gradual), side, character, radiation
Relation to the cycle, last period
Vomiting (torsion), fever, discharge
Sexual history, contraception, IUD
Known cysts, prior surgery, prior ectopic
Urinary and bowel symptoms

Examination that discriminates

Vital signs, temperature
Abdominal tenderness, peritonism, the appendix point
Speculum: discharge, cervicitis
Bimanual: cervical motion tenderness, adnexal mass or tenderness; gently

Investigations

hCG
CBC, CRP
Urinalysis
Swabs for chlamydia and gonorrhoea
Transvaginal ultrasound with Doppler
CT if appendicitis or another non-gynaecological cause is likely

What the image changes

Look first. Then commit in the Ultrasound Lab.

The differential

Diagnosis	Favours	Against	Urgency
Ectopic pregnancy	Positive test, unilateral pain, empty uterus	Negative test	emergent
Ovarian torsion	Sudden severe unilateral pain, vomiting, enlarged ovary, a cyst or dermoid	Gradual onset, normal ovaries	emergent
Ruptured or haemorrhagic cyst	Mid-cycle, sudden, free fluid, a cyst with a lace-like pattern	No cyst, no fluid	urgent
Pelvic inflammatory disease	Fever, discharge, cervical motion tenderness, risk factors	No infection risk, afebrile	urgent
Appendicitis	Migration, anorexia, right-sided peritonism	Left-sided pain	emergent
Urinary tract infection or stone	Dysuria, haematuria, flank pain	Normal urine	urgent
Endometriosis flare, dysmenorrhoea	Cyclical, known diagnosis	Sudden new severe pain	routine

Pitfalls this pathway refuses

Excluding torsion because Doppler flow is present
Missing ectopic because 'she has an IUD'
Withholding analgesia while waiting for a diagnosis