›Cefoxitin 2 g IV every 6 hours is an acceptable single agent for penetrating abdominal trauma prophylaxis
›Penicillin allergy
›Ciprofloxacin 400 mg IV every 12 hours plus metronidazole 500 mg IV every 8 hours
›Gentamicin 5 to 7 mg/kg IV every 24 hours on adjusted body weight with level monitoring, plus metronidazole 500 mg IV every 8 hours
›Avoid gentamicin in significant renal impairment and in pregnancy where a beta-lactam alternative exists
›Duration
›24 hours of prophylaxis when a hollow viscus injury is repaired within a few hours with minimal contamination
›Treat as intra-abdominal infection for 4 to 7 days after source control when contamination is established or repair is delayed
›Add antifungal cover only for upper gastrointestinal perforation with delayed source control, recurrent leak, or immunosuppression
›Tetanus prophylaxis for penetrating wounds
›Tdap 0.5 ml IM if not up to date
›Tetanus immunoglobulin 250 units IM (500 units if the wound is heavily contaminated or more than 24 hours old) at a separate site for an under-immunised patient
Analgesia, antiemetics, and antipyretics
›Opioids, titrated with the examination in mind
›Document the abdominal examination immediately before each dose while the decision to operate is pending
›Fentanyl 0.5 to 1 mcg/kg IV every 30 to 60 minutes as needed (typical adult dose 25 to 50 mcg), preferred in haemodynamic instability
›Morphine 0.05 to 0.1 mg/kg IV every 2 to 4 hours as needed; avoid in renal failure and in haemodynamic instability
›Hydromorphone 0.2 to 0.5 mg IV every 2 to 3 hours as needed
›Opioid-sparing adjuncts
›Ketamine 0.1 to 0.3 mg/kg IV as an analgesic adjunct that preserves blood pressure
›Acetaminophen 1 g IV or orally every 6 hours, maximum 4 g in 24 hours (maximum 3 g in 24 hours with frailty, low body weight, or liver disease)
›Non-steroidal anti-inflammatory drugs
›Avoid them: platelet dysfunction, acute kidney injury during hypoperfusion, and anastomotic healing concern
›If one is nonetheless used for isolated musculoskeletal pain once bleeding and renal risk are excluded, ketorolac 15 to 30 mg IV every 6 hours, maximum 5 days, is the usual agent
›Nausea and fever
›Ondansetron 4 mg IV every 8 hours as needed; check a baseline QT and avoid stacking QT-prolonging drugs
›Treating fever does not treat the source; persistent fever after antibiotics should prompt a search for uncontrolled contamination or missed injury
Gastric decompression and supportive care
›Decompression and drainage
›Nasogastric tube to decompress the stomach, reduce aspiration risk, and check for blood
›Use an orogastric tube with midface trauma or a suspected basilar skull fracture
›Urinary catheter for output, unless urethral injury is suspected, in which case obtain a retrograde urethrogram first
›Nil by mouth
›Venous thromboembolism prophylaxis
›Mechanical prophylaxis with intermittent pneumatic compression from admission
›Add pharmacologic prophylaxis only once the surgeon confirms haemorrhage is controlled, usually 24 to 48 hours after operation
›Enoxaparin 30 mg subcutaneously every 12 hours, or 40 mg every 24 hours; unfractionated heparin 5000 units subcutaneously every 8 to 12 hours if renal function is poor
›Do not give pharmacologic prophylaxis while haemorrhage is uncontrolled or a return to theatre is anticipated
›Anticoagulant reversal for active bleeding or emergency surgery
›Warfarin: 4-factor prothrombin complex concentrate 25 to 50 units/kg IV dosed by INR and weight, plus vitamin K 10 mg IV
›Dabigatran: idarucizumab 5 g IV
›Factor Xa inhibitors: andexanet alfa (low-dose 400 mg IV bolus then 4 mg/min, or high-dose 800 mg IV bolus then 8 mg/min, by agent and timing of last dose), or 4-factor prothrombin complex concentrate 50 units/kg IV if andexanet is unavailable
›Antiplatelet-associated bleeding: platelet transfusion is not routinely beneficial; reserve it for surgical or neurosurgical bleeding
›Other supportive measures
›Stress ulcer prophylaxis with pantoprazole 40 mg IV daily for the ventilated or coagulopathic patient
›Glycaemic control: treat glucose above 10 mmol/l with an IV insulin infusion starting 0.05 to 0.1 units/kg/h, target 6 to 10 mmol/l, avoiding hypoglycaemia
›Early enteral nutrition after repair once the surgical team approves
Operative management and the open abdomen
›Definitive repair options
›Primary repair, resection with anastomosis, or resection with stoma, chosen by injury, contamination, and physiology
›Isolated extraperitoneal bladder rupture is managed non-operatively; intraperitoneal bladder rupture is always repaired
›Extraperitoneal rupture: urethral catheter drainage for 10 to 14 days, then a cystogram before removal
›Operate on an extraperitoneal rupture with bladder neck involvement, bone fragments in the bladder, rectal or vaginal injury, or planned pelvic fixation
›Damage-control laparotomy
›Control haemorrhage, control contamination by stapling off injured bowel with no anastomosis, temporary abdominal closure, resuscitate in ICU, return in 24 to 48 hours
›Triggers: pH below 7.2, temperature below 35 degrees Celsius, base deficit worse than -8 mmol/l, coagulopathy, more than 10 units of red cells, or operative time approaching the physiological limit
›Abdominal compartment syndrome
›Sustained intra-abdominal pressure above 20 mmHg with new organ dysfunction
›Measure bladder pressure every 4 hours in the at-risk patient (open abdomen, massive resuscitation, packing)
›Escalate: deepen sedation and analgesia, nasogastric and rectal decompression, neuromuscular blockade, drain free fluid, limit further crystalloid; decompressive laparotomy if pressure and organ dysfunction persist
›When therapy is not working after operation
›Persistent acidosis, rising lactate, or an ongoing pressor need: suspect missed injury, ongoing surgical bleeding, or abdominal compartment syndrome and return to theatre
›New fever, leukocytosis, or feculent drain output on days 3 to 5: suspect an anastomotic leak; image and re-operate
›Failure to clear lactate despite adequate products: recheck ionised calcium, fibrinogen, and core temperature and confirm mechanical haemostasis
›Non-operative pathways that do apply
›An anterior stab wound with no fascial penetration on local exploration: observe then discharge
›Solid organ injury without hollow viscus injury may be managed non-operatively with monitoring
Interventions to avoid or modify in this patient
›Airway and oxygen
›Intubation: resuscitate first, use ketamine induction, and have chest decompression ready because positive pressure can tension an occult pneumothorax
›Oxygen: titrate to target rather than applying high flow to everyone; 88 to 92 percent in chronic hypercapnic disease
›Sedation and analgesia
›Sedation: long-acting agents erase the serial abdominal examination before the patient is committed to surgery; use short-acting agents and record the pre-sedation exam
›Opioids slow the gut and soften peritoneal signs but should not be withheld; titrate short-acting agents and document the exam before each dose
›Non-steroidal anti-inflammatory drugs add bleeding and renal risk during hypoperfusion and raise anastomotic concern
›Circulatory support
›Fluid loading: large-volume crystalloid before haemorrhage control causes dilutional coagulopathy, hypothermia, acidosis, clot disruption, and bowel oedema that prevents fascial closure; give blood instead
›Vasopressors: pressing up the blood pressure while bleeding worsens mortality; use norepinephrine only as a short bridge or for distributive shock
›Mechanical circulatory support and the intra-aortic balloon pump: no role; the physiology is volume loss and contamination, not pump failure, and an intra-aortic balloon pump is contraindicated with aortic injury
›REBOA: Zone 1 occlusion is a time-limited bridge to laparotomy for exsanguinating abdominal haemorrhage; it does not treat contamination
›Haemostasis and anticoagulation
›Fibrinolysis is contraindicated with active haemorrhage; the indicated antifibrinolytic is tranexamic acid within 3 hours
›Pharmacologic venous thromboembolism prophylaxis is withheld until the surgeon confirms haemostasis; mechanical prophylaxis is used meanwhile
›Reverse existing anticoagulants for active bleeding or emergency surgery
›Diagnostic pitfalls that cause harm
›Diagnostic peritoneal lavage fluid confounds a later CT; choose one route by stability
›A urinary catheter passed before a retrograde urethrogram can convert a partial urethral tear to a complete disruption