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Postoperative care of patients after foreign body removal is similar to that for other abdominal procedures with the extent and frequency of monitoring and interventions dependent on the patient’s clinical condition and the type of procedure performed. General supportive care, including fluid therapy, electrolyte management, diligent nursing care, and pain medication, is indicated for all postoperative patients. Hypoproteinemia is a common problem associated with foreign bodies and can contribute to peripheral and pulmonary edema, GI edema, which may inhibit GI motility, and possibly dehiscence of surgical sites. In patients with a low albumin, low total protein, or low measured colloid osmotic pressure, administration of synthetic or biologic colloids may subsequently help preserve blood volume and reduce risk of peripheral edema formation.

Figure 5.9 (a) and (b) A longitudinal incision is made along the antimesenteric border of the smaller intestinal segment to create a larger opening (a). Sutures are first placed at the mesenteric and antimesenteric borders to align the intestinal segments for anastomosis.

Source: Brown [62]. Reproduced with permission from Elsevier.

For critically ill patients, perioperatively placed jugular or peripherally introduced central catheters facilitate fluid administration, patient monitoring, and total or partial parenteral nutrition, if needed. Central lines also reduce the need for venipuncture and generally last longer than peripheral catheters. Antibiotics are indicated for patients with concurrent septic peritonitis (see Chapter 11). Antiemetics, prokinetics, vasopressors, and inotropes may also be indicated in some patients.

Frequent monitoring of vital parameters including heart rate, pulse quality, capillary refill time, mucous membrane color, and blood pressure is important to ensure patient stability. Failure of the patient to show clinical improvements postoperatively or worsening of clinical signs after a period of apparent improvement, should prompt further investigation as this may herald the onset of some complications. Tachycardia, bounding or weak pulses, prolonged capillary refill time, low central venous pressure, and low systemic blood pressure could indicate hypovolemia due to inadequate fluid replacement, losses through the GI tract, or losses due to SIRS‐induced vascular leak or low oncotic pressure. Sepsis‐induced vasodilation, as evidenced by hypotension and bright pink or red mucous membranes, may also contribute to similar cardiovascular abnormalities. Increases in respiratory rate or effort should prompt thorough auscultation followed by radiographs of the thorax, as these could be signs of aspiration pneumonia, acute respiratory distress syndrome, fluid overload, or systemic inflammatory response/hypoproteinemia‐induced hydrothorax. Development of a fever postoperatively may indicate development of pneumonia or septic peritonitis.

Figure 5.10 Small intestinal plication secondary to a linear foreign body in a cat.

Figure 5.11 Perforation of the small intestine at the mesenteric border, secondary to a linear foreign body in a cat.

Healing of the GI tract occurs over several weeks to months, but the critical healing period is within the first three to five days postoperatively [63]. As such, postoperative gastrotomy, enterotomy, or resection and anastomosis patients should be monitored for evidence of dehiscence, particularly within the first five days. Fever, increasing volumes of peritoneal effusion, and increasing quantity of neutrophils or the presence of toxic neutrophils in the effusion are consistent with development of postoperative septic peritonitis and should prompt further investigation. Ultrasonography can be used to identify free fluid in the abdomen. Abdominocentesis, with or without the aid of ultrasound, should be taken to obtain a sample of abdominal fluid for biochemical evaluation and cytology (see Chapter 3, Video 3.1). Abnormal glucose and lactate ratios or the presence of bacteria in fluid taken directly from the abdomen (but not taken from a drain) are consistent with septic peritonitis [64]. However, incisional dehiscence rates following gastrotomy or enterotomy are relatively low. A study evaluating incisional dehiscence rates for 247 dogs undergoing enterotomy for GI foreign body removal found only a 2% dehiscence rate in these specific patients [65].

The need for enteral nutrition should be taken into account at the time of surgery; and a surgically placed feeding tube should be strongly considered in animals with septic peritonitis, multiple GI incisions, resection and anastomosis, or those with preoperative hypoproteinemia. Early enteral nutrition is important to provide nutrients for repair and rapid return to function of the GI tract and is preferred over parenteral nutrition. Early enteral nutrition after colonic resection and anastomosis shortened time until return of GI motility and maintained nutritional status more effectively than total parenteral nutrition [66]. While controlling for other variables, in a study by Liu et al., dogs that received enteral or parenteral nutrition within 24 hours postoperatively had significantly shorter hospitalization length (by 1.6 days) compared with dogs that did not receive early nutrition [67]. Comparatively, dogs with septic peritonitis receiving any parenteral nutrition were significantly less likely to survive than dogs that did not receive parenteral nutrition and had a significantly longer hospitalization, although the dogs receiving parenteral nutrition may have been sicker than dogs able to be fed enterally [68].

Choices of tube entry site include nasal, esophageal, or gastric. If the animal fails to eat shortly after surgery, a perioperatively placed feeding tube facilitates adequate nutrition without need for a second episode of general anesthesia specifically for tube placement. Current nutritional recommendations are to meet resting energy requirements, rather than applying an illness factor, as higher supplementation rates have been associated with higher complication rate and mortality [69, 70]. If unable to provide complete enteral feedings, provision of enteral glutamine, the energy source for enterocytes, may be beneficial. Glutamine can enhance the immune system, decrease bacterial translocation, increase mucous production [71], and as a supplement, glutamine has been shown to decrease morbidity in certain critically ill patient populations [72]. Dogs receiving glutamine after distal gastrectomy had a significantly shorter time to return of GI motility compared to placebo controls [69]. The published dose of glutamine is 0.5 g/kg/day divided into two to three doses [73, 74].