What is a classic scientific paper? In my mind, it is one that changes the way we think and shakes the up status quo, research that alters the way we practice. Here are four summaries of classic articles chosen from a list that is admittedly subjective. You’ll want to implement their findings posthaste.
Swab all IV ports with alcohol
Currently, there are no published recommendations for handling IV fluid bags in veterinary medicine. In many practices, fluid bags are used for several patients. “Hang time” can last several days. “Flushies” are often made by drawing fluid from a “hung” bag into multiple 3-ml syringes. How often do these habits lead to bacterial contamination of IV fluid bags?
A classic study1 led by Julien Guillaumin, Doct Vet, DACVECC, DECVECC, a board-certified criticalist, assessed the rate of bacterial contamination of IV fluid bags and IV ports in a veterinary emergency room and intensive care unit setting.
The study used 90 IV fluid bags of lactated ringers solution (LRS). Bundles of three bags were hung for 11 days near a sink and supplies bins. The experiment was repeated 10 times. Bags were punctured with a sterile needle three times daily to simulate clinical use. Injection ports were swabbed with culturettes and 50 ml of fluid were collected on days one, two, four, seven, and 10.
Results showed the rate of injection port contamination increases over time. Only one bacterial phenotype was isolated in each case of port contamination. At day seven, port contamination of fluid bags in the ER and ICU were 30 percent and 33 percent, respectively. Port contamination was higher in fluid bags hung in the sink areas than in the bin area, suggesting hospital sinks are an important source of bacterial contamination.
Fluid contamination at day seven was 4.4 percent overall, and 6.7 percent in the ER, which is higher than most studies conducted in human medicine. It was postulated that bacteria were introduced into the fluids during puncture of bags.
Out of 90 bags, fluid contamination developed in four bags, all of which were in the ER. Both gram positive and negative bacteria were isolated from the contaminated fluid: Corynebacterium sp., Micrococcus sp., Pseudomonas sp., and Staphylococcus sp.
The study shows there is a significant relationship between the length of time fluid bags are hung in a veterinary setting and fluid/port contamination.
- Bacteria can grow in IV fluids, which can lead to bloodstream infections.
- Access ports of IV bags and IV catheters should be swabbed with 70 percent alcohol cotton swabs.
- IV fluid bags should not be used to make “flushies” because of the risk of contamination. You can buy prefilled saline syringes to decrease the risk of bloodstream infection. (Note from the author: they cost about 60 cents each.)
- The same fluid bag should not be used in more than one patient.
Weigh the pros and cons of enteroplication
Intussusception is most usually seen in dogs under one year of age. The most common initial complaints are vomiting and diarrhea. The location of the intussusception is most often ileocolic.
Enteroplication is a procedure designed to plicate the small intestine to create permanent adhesions between loops. The procedure is meant to decrease post-op recurrence and complications… except that it has never been proven.
Aric Applewhite, DVM, DACVS, a board-certified surgeon, and his team published a classic study2 involving 35 dogs with intestinal intussusception. Complications included recurrence, obstruction, and strangulation. The recurrence rate, as well as the likelihood of a revision surgery, was similar between patients who had an enteroplication and those who did not.
- Plications should be from the duodenocolic ligament to the ileocolic junction.
- Bends should be gentle, not tight.
- Sutures should be placed at intervals that will prevent entrapment and strangulation of the rest of the bowel.
Inflating a cuff is not a benign procedure
Anesthetized and intubated cats often need to be repositioned, especially during dental procedures. This can lead to tracheal tears.
A classic 2000 study3 involved 20 anesthetized and intubated cats. All had a confirmed or presumed tracheal rupture after the procedure.
Most cats had a prophylactic dental procedure that required changing the head position multiple times. All tears were in a location associated with the cuff. Therefore, the study was unable to confirm whether repositioning was a risk factor or if overinflation of the cuff before a dental procedure was the cause.
Two cats did not make it through treatment. One passed prior to getting treatment and one died after surgical repair. Both cats were intubated at the same clinic, where a coat hanger type of stylet was inserted past the end of the endotracheal tube (ETT). The injury again was in the area of the cuff. Therefore, it is unclear whether the stylet was the only factor and/or if the cuff damaged the site.
Using a high-pressure, low-volume cuff or a low-volume, high-pressure cuff did not seem to be a risk factor.
All patients exhibited SQ emphysema upon presentation. Most cats were treated with conservative therapy. For the cats who did not respond to medical treatment, who were open-mouth breathing, and who had worsening SQ emphysema despite oxygen therapy, immediate surgical repair was recommended.
All patients who survived had no additional respiratory issues during their lives.
- As long as patients respond to medical management, most do not require surgical intervention.
- Never reposition a patient while the tube is attached to the anesthesia hose.
- Never overinflate the cuff.
Partial foot amputation is possible
Until 2005, we believed neither weight-bearing digits nor two adjacent toes could be amputated, as doing so would leave the patient severely lame. We thought limb amputation was the only option. That belief changed when Liptak et al., published a classic study4 proving partial foot amputation is a perfectly valid option to treat tumors of the digits.
In this study of 11 dogs, nine mid-foot (digits 3 and 4) and two lateral foot (digits 4 and 5) amputations were performed. Post-op survival rate, tumor control, functionality of the limb, and owner satisfaction were observed.
Patients ranged from four to 13 years of age (median age was eight) and weighed from 4.5 to 50 kg (median weight was 10 kg). All patients had cancerous processes: Mostly mast cell tumors (55 percent), as well as osteosarcoma, soft-tissue sarcoma, synovial cell sarcoma, and squamous cell carcinoma. All four limbs were affected. One dog had a limb amputation because of incomplete margins. Some dogs were also treated with radiation or chemotherapy.
All dogs experienced lameness immediately post-op, but eight of the 11 dogs (73 percent) returned to normal function in about one month. Three dogs (27 percent) had mild ongoing lameness, according to their owners. This occurred in two patients over 25 kg whose front limb digits were affected.
One caveat: carpometacarpal (CMC) or tarsometatarsal (TMT) joint amputation should be avoided because of disruption of the collateral ligaments and palmar and plantar fibrocartilage, which may lead to instability and limping.
- Partial foot amputation should be considered when dealing with tumors of the digits.
- Overall, all owners were either satisfied or very satisfied with the results.
- Limb function was described as good to excellent.
These four classic articles changed how we treat specific conditions. This timeless information should be shared with your team. It can be used in everyday practice for the benefit of your patients.
Phil Zeltzman, DVM, DACVS, CVJ, Fear Free Certified, is a board-certified veterinary surgeon and author whose traveling surgery practice takes him all over Eastern Pennsylvania and Western New Jersey. You can visit his website at DrPhilZeltzman.com. He also is cofounder of Veterinary Financial Summit, an online community and conference dedicated to personal and practice finance (vetfinancialsummit.com). AJ Debiasse, a technician in Blairstown, N.J., and Kelly Serfas, a certified veterinary technician (CVT) in Bethlehem, Pa, contributed to this article.
1 J. Guillaumin et al. “Influence of hang time and location on bacterial contamination of intravenous bags in a veterinary emergency and critical care setting.” J Vet Emerg Crit Care 2017, Vol 27, N 5, p. 548-554.
2 A Applewhite et al. “Complications of enteroplication for the prevention of intussusception recurrence in dogs: 35 cases (1989–1999).” JAVMA 2001, Vol 219, N 10, p. 1415-1518.
3 S. Mitchell et al. “Tracheal rupture associated with intubation in cats: 20 cases (1996-1998)”. JAVMA 2000, Vol 216, N 10, p. 1592-1595.
4 J. Liptak et al. “Partial foot amputation in 11 dogs.” JAAHA 2005, Vol 41, N 1, p. 47-55.