Figure 5.3 Intraoperative photograph showing the removal of a large nasogastric tube fragment (1.3 cm diameter, 90 cm long) through a full thickness enterotomy in the right dorsal colon. This horse presented with acute signs of colic, but had no known history of prior nasogastric intubation complications. It was presumed that the nasogastric tube fragment had been acquired prior to the current ownership of the horse and did not cause problems until it migrated to the transverse colon and caused obstruction.
Source: Courtesy of Isabelle Kilcoyne.
Prevention
Prevention of inadvertent administration of fluids into the lungs is an essential part of nasogastric intubation procedures. Please refer to the section describing misplacement of nasogastric tubes for specific preventative procedures. Careful attention to all precautions throughout the nasogastric intubation procedure will help to minimize complications.
Diagnosis
Development of respiratory distress immediately following a nasogastric tube procedure is highly suggestive of inadvertent pulmonary administration of fluid. Signs may be delayed by a few days in cases with a small amount of mineral oil aspiration. Diagnosis of contamination of the lungs with mineral oil, also described as mineral oil‐induced pneumonitis or lipoid pneumonia, is based on a history of mineral oil administration, radiographic or ultrasonographic evidence of pneumonia, and the identification of oil in tracheal wash or bronchoalveolar lavage samples [13–17].
Treatment
If a small amount of clean water is inadvertently administered into the lungs, the horse should be placed on anti‐inflammatory treatment and antimicrobial therapy to prevent pneumonia [1]. Administration of larger volumes of fluid may require additional supportive care, such as furosemide to treat pulmonary edema, bronchodilators, and intranasal oxygen therapy. Inadvertent intratracheal administration of certain medications (e.g. deworming drenches) [12] and mineral oil [13, 15–19] may have fatal consequences, even with aggressive treatment. These horses should be aggressively treated with antimicrobial therapy, anti‐inflammatory medications, bronchodilators, nebulization, and intra‐nasal oxygen [13–17]. Repeated bronchoalveolar lavage and lung lobectomy has been reported to be helpful in people with mineral oil aspiration, but it has not been described in the equine case reports [16, 17]. There is one report of successful treatment of lipoid pneumonia, from aspiration of mineral oil, in which dexamethasone treatment was used [14]; however, other authors have reported use of corticosteroids as part of their treatment efforts in cases with unsuccessful outcomes [15].
Expected outcome
A small amount of clean water inadvertently administered into the lungs may be tolerated; however, the horse should be placed on prophylactic treatment to prevent pneumonia [1]. In contrast, a small amount of mineral oil aspirated into the lungs in nearly invariably fatal [13–17].
Sinusitis
Definition
Sinusitis is the accumulation of suppurative exudate within the paranasal sinuses of the horse and typically results in malodorous nasal discharge with or without pyrexia.
Risk factors
Prolonged or repeated nasogastric intubation
Contamination of the nasal cavity with blood or gastrointestinal reflux, especially during general anesthesia [18, 19].
Prolonged intubation is a significant risk factor in people [20]
Pathogenesis
Unilateral or bilateral sinusitis has been described as a rare complication of nasogastric intubation [18, 19]. Pathogenesis is assumed to be related to overwhelming of normal sinus defense mechanisms by impediment of normal sinus drainage (inflammation and swelling of mucosa secondary to indwelling tubes), increased bacterial load (prolonged intubation, use of a contaminated tube, or feed contamination of sinuses), or propagation of bacterial growth (blood contamination).
Prevention
Nasogastric tube‐associated sinusitis may be minimized by prophylactically lavaging the nasal passages if they are contaminated with gastrointestinal reflux during colic surgery and by using clean, disinfected nasogastric tubes for as short a time as possible [18].
Diagnosis
Clinical signs are the development of suppurative nasal discharge and fever [18]. Radiographs of the paranasal sinuses and endoscopy of the upper respiratory tract can localize the disease to the paranasal sinuses.
Treatment
Treat with systemic antimicrobial therapy and lavage of the affected sinuses via trephination. Sinusotomy via sinonasal flap may be necessary in selected cases.
Expected outcome
Prognosis with appropriate treatment should be good.
References
1 1 Fehr, J. (2013). Nasogastric intubation. In: Practical Guide to Equine Colic (ed. L.L. Southwood), 38–44. Ames: John Wiley & Sons, Inc.
2 2 Lopes, M.A.F. (2003). Administration of enteral fluid therapy: methods, composition of fluids and complications. Equine Vet. Educ. 15: 107–112.
3 3 Hardy, J., Stewart, R.H., Beard, W.L. et al. (1992). Complications of nasogastric intubation in horses: nine cases (1987–1989). J. Am. Vet. Med. Assoc. 201: 483–486.
4 4 Gillen, A., Cuming, R., Schumacher, J. et al. (2015). Guttural pouch perforation caused during nasogastric intubation. Equine Vet. Educ. 27: 398–402.
5 5 Wooldridge, A.A., Eades, S.C., Hosgood, G.L. et al. (2002). Effects of treatment with oxytocin, xylazine butorphanol, guaifenesin, acepromazine, and detomidine on esophageal manometric pressure in conscious horses. Am. J. Vet. Res. 63: 1738–1744.
6 6 Cribb, N.C., Kenney, D.G., and Reid‐Burke, R. (2012). Removal of a nasogastric tube fragment from the stomach of a standing horse. Can. Vet. J. 53: 83–85.
7 7 Rashmir‐Raven, A.M., DeBowes, R.M., Gift, L.J. et al. (1991) What is your diagnosis? J. Am. Vet. Med. Assoc. 198: 1991–1992.
8 8 Craig, D.R., Shivy, D.R., Pankowski, R.L, et al. (1989). Esophageal disorders in 61 horses: results of nonsurgical and surgical management. Vet. Surg. 18: 432–438.
9 9 Kruger, K. and, Davis, J.L. (2013). Management and complications associated with treatment of cervical oesophageal perforations in horses. Equine Vet. Educ. 25: 247–255.
10 10 DiFranco, B., Schumacher, J., and Morris, D. (1992). Removal of nasogastric tube fragments from three horses. J. Am. Vet. Med. Assoc. 201: 1035–1037.
11 11 Baird, A.N. and True, C.K. (1989). Fragments of nasogastric tubes as esophageal foreign bodies in two horses. J. Am. Vet. Med. Assoc. 194: 1068–1070.
12 12 Stauffer, B.D. (1982). Stomach intubation accidents. J. Am. Vet. Med. Assoc. 181: 448.
13 13 Metcalfe, L., Cummins, C., Maischberger, E. et al. (2010). Iatrogenic lipoid pneumonia in an adult horse. Irish Vet. J. 63: 303–306.
14 14 Henninger, R.W., Hass, G.F., and Freshwater, A. (2006). Corticosteroid