GDV in a 6yo Great Dane — Stabilization and Surgical Decision

Alright, 6yo MN Great Dane with GDV. This is a critical emergency where every minute counts for stabilization before surgery. My approach is aggressive resuscitation concurrent with primary survey.

Immediate Actions (First 30 Minutes):

Airway/Breathing: Ensure patent airway, assess respiratory effort. Oxygen supplementation via flow-by or nasal cannula.

Circulation: This patient is in shock (HR 180, weak pulses, CRT 4s).

IV Access: Place two large-bore (18g or 16g) cephalic catheters*. Avoid saphenous veins initially due to caudal vena cava compression.
* Fluid Resuscitation:
* Initiate LRS at 90ml/kg/hour shock rate. My preference is to give a 20ml/kg bolus and reassess.
Reassess perfusion parameters (HR, pulse quality, CRT, mentation) after every* 10-15ml/kg bolus.
* If hypovolemic shock is refractory to 30-40ml/kg crystalloids, consider hypertonic saline (3-5ml/kg over 10 min) to rapidly expand intravascular volume, or hetastarch (5ml/kg bolus) if severe hypotension persists.

Decompression: This is life-saving and should happen immediately after securing IV access and initiating fluids.

* Trocarization: Perform gastric decompression with an 18g over-the-needle catheter. Locate the most tympanic area, usually caudal to the last rib on the right side. Prep aseptically. This will alleviate pressure on the diaphragm and caudal vena cava, improving ventilation and venous return.

Pain Control: GDV is exquisitely painful.

* Lidocaine: Bolus 2mg/kg IV slowly, then start a CRI at 50µg/kg/min. This also helps with potential VPCs.
* Maropitant: 1mg/kg IV for nausea and visceral pain.
* Opioid: Full mu agonist (e.g., fentanyl 2-5µg/kg IV bolus, then CRI 2-5µg/kg/hr) once BP improves.

Initial Diagnostics (STAT): While stabilizing, obtain a minimum database.

* Venous Blood Gas: Assess acid-base, electrolytes.
* Lactate: Crucial prognostic indicator. Serial lactates guide resuscitation. A lactate > 6mmol/L is a poor prognostic indicator, but improvement with fluids is good.
* PCV/TS: Baseline.
* Glucose: Hypoglycemia can occur with shock.
* Azostick/Chem 8: Kidney function.

Ongoing Stabilization & Pre-OR Preparation:

* Arrhythmias: Monitor ECG. GDV commonly causes ventricular premature contractions (VPCs) due to myocardial ischemia and reperfusion injury. If VPCs are frequent (>20/min), multifocal, R-on-T phenomena, or cause hemodynamic compromise, continue lidocaine CRI.
* Antibiotics: Initiate broad-spectrum IV antibiotics immediately to cover for bacterial translocation.
* My protocol: Ampicillin/sulbactam 30mg/kg IV q8h + Enrofloxacin 10mg/kg IV q24h.
Blood cultures BEFORE antibiotics* is my general sepsis rule, but in GDV, time is of the essence; antibiotics often start empirically once blood samples are drawn for other critical diagnostics.
* Transfusion: Check PCV. If hemorrhagic effusion from gastric necrosis is suspected, or if PCV drops significantly with fluids, prepare for a pRBC transfusion based on clinical signs (tachycardia, tachypnea, lethargy) rather than an arbitrary PCV.
* Reassessment: Continuously reassess shock parameters. If the patient remains hypotensive despite 60ml/kg crystalloids and adequate decompression, consider vasopressors. My first choice is norepinephrine 0.1-2µg/kg/min CRI.

When to go to OR:
The patient goes to surgery as soon as they are hemodynamically stable and responding to resuscitation. This is typically when:
* Heart rate is decreasing (<120 bpm).
* Pulse quality is strong.
* CRT is normal (<2 seconds).
* Blood pressure is improving (MAP > 60 mmHg).
* Lactate is trending downwards (clearing).

Do not rush a crashing patient to surgery. Stabilize the shock first, or they will decompensate under anesthesia. Our goal is 1-2 hours of aggressive stabilization before anesthesia induction.

This is a critical patient requiring immediate, aggressive stabilization. My focus is always on hemodynamic stability and robust analgesia.

Here's my approach:

1. Immediate Stabilization (Concurrent Priorities):

* Vascular Access: Two large-bore IV catheters (16-18 gauge) in peripheral veins (cephalic or saphenous). Avoid jugulars initially due to potential for caval compression by the distended stomach.
* Shock Fluids:
* Start with rapid crystalloid boluses: LRS or Plasmalyte, 30-45 mL/kg over 15-20 minutes. Reassess perfusion parameters frequently.
* Consider a small bolus of hypertonic saline (4 mL/kg over 5 minutes) if profound hypovolemia/shock, followed immediately by crystalloids.
* Hold off on colloids initially unless crystalloids are insufficient, given current controversies.
* Gastric Decompression: This is life-saving and should not wait.
* Attempt orogastric tube passage immediately. Measure to the last rib, lubricate generously. If successful, lavage stomach.
* If unable to pass a tube, proceed with temporary trocarization: clip and prep the right paralumbar fossa over the most distended area. Insert a 14-16 gauge over-the-needle catheter to release gas. Aim to relieve pressure, not fully decompress.
* Analgesia: This patient is in severe pain.
* Full mu-opioid: Fentanyl 3-5 µg/kg IV bolus or Hydromorphone 0.1 mg/kg IV.
* Diagnostics:
* STAT bloodwork: PCV/TS, blood gas, electrolytes, lactate. Lactate >6 mmol/L is prognostic.
* ECG: Monitor for ventricular arrhythmias (VPCs), common in GDV patients.
* Antibiotics: Broad-spectrum IV. Cefazolin 22 mg/kg IV immediately.
* Anti-emetic: Maropitant 1 mg/kg IV.

2. Pre-Anesthetic Plan (Once stable for OR transport):

* Reassess: Ensure heart rate is decreasing, pulses are strengthening, CRT is improving, and lactate trending down.
* Monitoring: Continuous ECG, SpO2, NIBP, EtCO2 (post-intubation). An arterial line for continuous BP monitoring is ideal in this critical patient (ASA IV-V). Place esophageal temperature probe.
* Pre-oxygenation: 100% oxygen by mask for 5 minutes prior to induction.
* Premedication: My ASA IV/V protocol:
* Fentanyl 3-5 µg/kg IV bolus (if not given already as initial analgesia)
* Midazolam 0.2 mg/kg IV
* Avoid alpha-2 agonists (dexmedetomidine) or acepromazine in this hemodynamically compromised patient.

3. Anesthetic Protocol (OR):

* Induction:
* Etomidate 1-2 mg/kg IV slowly to effect. This is my drug of choice for hemodynamically unstable patients due to minimal cardiovascular depression.
* Alternative: Alfaxalone 1-2 mg/kg IV.
* Absolutely avoid a propofol bolus in this hemodynamically unstable patient due to dose-dependent vasodilation and myocardial depression.
* Intubation: Rapid sequence intubation with a cuffed endotracheal tube. Inflate cuff to prevent aspiration.
* Maintenance:
* Isoflurane or Sevoflurane. Keep MAC as low as possible (e.g., 0.8-1.0 MAC) to minimize cardiovascular depression.
* Support with a multimodal CRI for MAC sparing and superior analgesia.
* CRI: Fentanyl 5-10 µg/kg/hr. Once stable, add Lidocaine 25-50 µg/kg/min + Ketamine 2-5 µg/kg/min (FLK).
* Ventilation: Positive pressure ventilation will likely be required due to large size, abdominal pressure, and expected hypoventilation under anesthesia. Target EtCO2 35-45 mmHg.
* Fluid Support: Continue IV fluid support. If hypotension persists despite adequate fluids and low inhalant, consider vasopressors (e.g., Norepinephrine 0.05-0.5 µg/kg/min, Dopamine 5-10 µg/kg/min).
* Arrhythmia Management: Be prepared for reperfusion arrhythmias, especially VPCs, during stomach derotation. Have Lidocaine ready: 2-4 mg/kg IV bolus, followed by 25-80 µg/kg/min CRI if needed.

4. Post-Operative Analgesia:

* Continue opioid CRI (Fentanyl) for at least 12-24 hours.
* Once hemodynamically stable and renal function confirmed, consider NSAID (Carprofen 4.4 mg/kg SC or Meloxicam 0.1 mg/kg IV).
* Local anesthetic infiltration of the abdominal incision site.

Alright, GDV. This is a rural emergency. You don't have time to second guess. Get to work.

Here’s my protocol:

Immediate Stabilization (Simultaneously):

* IV Access & Fluids: Place two large-bore (16-18 gauge) IV catheters in the cephalic veins. Hit him with a rapid bolus of LRS – 60-90 mL/kg, given as fast as you can push it. Reassess perfusion after 15-20 minutes and repeat if needed. This dog is in severe shock.
* Decompression:
* Trocharization first: Don't waste time trying to pass a tube if he's that distended and tachycardic. Find the point of maximum distension, typically on the right side, caudal to the last rib, just ventral to the lumbar epaxial muscles. Use a 14-gauge over-the-needle catheter. Push it in, listen for the whoosh. This buys you critical time by improving venous return and diaphragm function.
* Orogastric Tube: Once trocharized, attempt to pass a well-lubricated stomach tube. Measure from nose to the last rib. A mouth speculum is essential. If you can pass it, lavage the stomach until clear. If not, don't waste too much time – get to surgery once stabilized enough.
* Analgesia: Give Tramadol 4 mg/kg IV slowly. I know it's controversial for severe pain, but it's what I have, and it's better than nothing.
* Antibiotics: Start broad-spectrum. Clavamox 22 mg/kg PO (if patient can swallow and you have injectable to use now, otherwise start with PO post-op) or if I'm concerned about translocation and have nothing else, I've used Ceftiofur 2.2 mg/kg IM (off-label for dogs, but gets a broad spectrum on board fast).
* Arrhythmias: Monitor pulse quality constantly. If you have an ECG, watch for ventricular arrhythmias. I don't typically stock Lidocaine for SA, but if I did, 2 mg/kg IV bolus is the go-to if they're severe.

Pre-operative Prep:

* While stabilizing, get the abdomen clipped wide (sternum to pubis, flank to flank) and an initial chlorhexidine scrub done.

Anesthesia (Injectable Protocol):

* Induction: Once perfusion is improving, induce with Xylazine 1 mg/kg IV slowly, followed by Ketamine 5 mg/kg IV slowly to effect. If I have Propofol, 2-4 mg/kg IV to effect can provide a smoother induction. Intubate immediately. Provide oxygen if you have it.
* Maintenance: I don't have an anesthesia machine at the farm. Maintain with repeated small boluses of Xylazine/Ketamine IV as needed to keep a surgical plane. Monitor vitals closely.

Surgery (Ventral Midline Exploratory & Gastropexy):

* Approach: Standard ventral midline incision.
* De-rotation: Confirm the stomach’s position. De-rotate counter-clockwise if looking from the dog's head. The pylorus should move from the left dorsal abdomen to the right ventral.
* Assess Viability: Inspect the stomach wall and spleen. Necrotic areas on the stomach may need resection (rare in primary GDV). If the spleen is severely congested or necrotic, a splenectomy may be necessary.
* Gastropexy: My standard is an incisional gastropexy.
* Make a 4-5 cm incision through the seromuscular layer of the pyloric antrum.
* Make a matching incision through the peritoneum and transversus abdominis muscle on the right abdominal wall, just caudal to the last rib.
* Suture the stomach incision to the abdominal wall incision with simple interrupted or continuous absorbable suture.

Post-operative Care:

* Continue IV fluids for at least 24-48 hours.
* Analgesia: Meloxicam 0.1 mg/kg PO SID starting 24 hours post-op (once stable and gut sounds are good). Continue Tramadol 4 mg/kg PO BID-TID for 3-5 days.
* Antibiotics: Clavamox 22 mg/kg PO BID for 7-10 days.
* Monitor for arrhythmias, pain, vomiting, and recurrence. Introduce small, frequent meals of bland food once stable and non-vomiting. Strict rest for 2-3 weeks.

This is a critical case. Move fast, rely on your hands, and use what you've got.