Page 103 - JSOM Spring 2018

canines. The same investigators reported their findings us- and hypotension; have naloxone on hand to counter adverse
30
ing this technique in clinical cases of GDV as compared with effects of the opioid μ-agonist, if needed. In addition, avoid
the standard GNDC techniques described in the previous sec- administering over-the-counter nonsteroidal antiinflamma-
tion. In clinically affected dogs suffering GDV, the G-catheter tory drugs developed for humans (e.g., ibuprofen, naproxen,
31
technique did not differ significantly from standard GNDC in meloxicam, aspirin) or corticosteroids (e.g., dexamethasone,
regard to safety, time to place, success rate, complications, and methylprednisolone, prednisone, hydrocortisone).
decompression rate. The technique may be a viable tool for the
tactical or SOF medic during situations when surgical delays A Brief Look Into Surgery
are unavoidable (e.g., prolonged field care). Gastric repositioning with gastropexy, to prevent volvulus
recurrence, is the surgical treatment of choice. Surgical man-
Fluid Resuscitation agement of GDV involves an open exploratory laparotomy
Fluid resuscitation to restore circulatory support and improve via a large, ventral, midline incision while under general an-
tissue perfusion and oxygenation is best accomplished via IV esthesia. Minimally invasive techniques discussed previously
or IO administration. For IV access, placing two large-bore for performing a prophylactic gastropexy are not applicable
catheters (14–18-gauge). IMPORTANT: Because of the ab- for correction of GDV. These techniques make it difficult to
dominal tourniquet effect of gastric distention, when estab- appropriately perform gastric repositioning and to visualize
lishing IV or IO access in a patient with GDV, always choose a organs and structures within the abdominal cavity to assess
location in the cranial half of the body (IV: cephalic vein in the their viability.
forelimb or external jugular vein; IO: proximal humerus). The
ideal fluid choice is one or a combination of the following : When combined with repositioning, gastropexy reduces the
5,6
recurrence rate of GDV from 80% to 5% or lower. Recur-
24
• Isotonic electrolyte crystalloid solution (e.g., Plasmalyte- rence rates after surgical correction may range from 0% to
A [Baxter, http://ecatalog.baxter.com], lactated Ringer’s 20% and largely depend on the open gastropexy technique
®
solution) used; recurrence rates are lowest with incisional gastropexy
• Hypertonic saline solution techniques. 24–27 Gastropexy does not prevent simple GD,
• Synthetic hydroxyethyl starch solution (e.g. Hextend only volvulus. The recurrence risk of GD without volvulus is
®
[Biotime, http://www.biotimeinc.com], Hespan [B. reported to range from 3.3% to 7.0%. Depending on the
24
®
Braun Medical, http://www.bbraunusa.com], Voluven viability of the stomach wall (gastric necrosis) and spleen,
®
[Fresenius-Kabi Norge, https://www.fresenius-kabi.com], surgical intervention may also require partial removal of the
or VetStarch [Zoetis Services, https://www.zoetisus.com). stomach (partial gastrectomy) as well as removal of the spleen.
®
A splenectomy is performed if there is splenic torsion causing
Suggested fluid resuscitation protocol (doses provided are for strangulation of splenic vasculature and splenic infarction.
25kg OpK9s):
Postsurgical recovery
• Isotonic crystalloid: 20mL/kg (500mL) The recovery time will depend on the severity and extent of
• 3%–7.5% Hypertonic saline: 5mL/kg (125mL) surgery as well as development of any postoperative compli-
o o Limit hypertonic saline administrations to no more than cations. Barring any major complications and based on the
2 aliquots to prevent clinically relevant hypernatremia OpK9s assigned mission (e.g., detection versus apprehension),
• Colloid only (low-molecular-weight 130/0.4 preferred) recommended recovery times range from 14 to 21 days. An
o o 5–10mL/kg (125–250 mL) adequate recovery time is important to help ensure all surgical
incisions have formed a tight, stable closure and the suture
Resuscitative goals in the prehospital or field environment line at the gastropexy site has formed permanent adhesion
include acquisition of palpable femoral pulse and improved to the abdominal wall. Postsurgical complications associated
mentation, and MAP higher than 65mmHg; systolic blood with GDV may include cardiac dysrhythmias, delayed stom-
pressure, 80–90mmHg (if ability to measure blood pressure ach and intestinal motility and function, vomiting, dehiscence
is available); reassess perfusion parameters after each fluid of surgical incisions, gastrointestinal ulceration, postopera-
bolus; and reassess the casualty frequently to check for recur- tive infections (sepsis), peritonitis, pancreatitis, disseminated
rence of shock. intravascular coagulation, and/or electrolyte and acid–base
disturbances. 4,6,32,33
Miscellaneous Prehospital Treatments
If available, provide oxygen supplementation and analge- Prognosis
sia. GDV is an extremely painful condition; therefore, a full
μ-opioid agonist such as fentanyl and/or morphine is the pre- GDV mortality rates depend on many perioperative factors.
ferred analgesic drug. Consider the following dosages (for Although mortality rates higher than 45% are reported even
25kg OpK9s): with prompt surgical intervention, postsurgical mortality
4
rates more commonly have been shown to be as low as 10%
• Fentanyl: 5μg/kg (125μg) IV/IO or intramuscular (IM) and survival rates often approach 80%. Prompt and ap-
2,9
every 30–45 minutes propriate treatment is the most important factor influencing
• Morphine: 0.2–0.5mg/kg (5–10mg) IV/IO/IM every 1–4 survival. 9,32,33 One study revealed that timely preoperative sta-
hours, administered very slowly IV/IO. bilization (i.e., gastric decompression, hemodynamic resuscita-
tion) significantly lowered the mortality rate to 10% overall.
9
When administering opioids to a sick or injured OpK9, con- Postoperatively, negative prognostic indicators include post-
sider the following: Always start at low end of the dosage operative cardiac arrhythmia, splenectomy, or splenectomy
range and titrate to effect; monitor for respiratory depression with partial gastric resection. 32,33 The overall prognosis for

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