Page 209 - Basic Monitoring in Canine and Feline Emergency Patients

Normal IAP (pressure = 0–20 cmH O) nary bladder, has been investigated and validated in
2
human medicine and remains the accepted surrogate
VetBooks.ir Surgery, abdominal trauma, measure for IAP in clinical use in people. There are
no known validation studies evaluating IAP in vet-
ascites, gastric dilation and
volvulus, sepsis erinary patients. However, using intravesical pres-
sure measurement makes it possible to measure IAP
in a simpler way with equipment readily available
to any veterinary practitioner.
IAH (pressure >20 cmH O) The simplest and most practical method of meas-
2
uring IAP can be accomplished utilizing the urinary
bladder and a water manometer (see Fig. 10.3). The
urinary bladder is an intra-abdominal and extra-
Sustained IAP >20 cmH O peritoneal organ with a compliant wall. It acts as a
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passive reservoir of urine and is capable of trans-
mitting abdominal pressure without imparting any
additional pressure from its own musculature. The
Decreased oxygen delivery to intra-abdominal urinary bladder should not be utilized in any
organs leading to organ hypoxia and patient with pre-existing bladder disease or those
life-threatening ACS with bladder trauma since the bladder should be
allowed to heal under those circumstances. Instead,
a different organ such as the stomach could be used
for those patients. Performing the intragastric pres-
sure is a surrogate for measuring IAP in human
respiratory research. However, there is conflicting
evidence for the relationship between intragastric
pressure and IAP, so using the bladder is preferred
Untreated ACS may lead to acute kidney injury, if possible in humans (and likely is also preferred
oliguria or anuria, hepatic dysfunction, in animals).
hypotension or patient death
A commercially available IAP monitoring system
(AbViser) can be used in place of a water manom-
Fig. 10.2. Visual representation of the stages from eter. This system is directly connected to the
increased intra-abdominal pressure to abdominal patient’s urinary catheter and it measures IAP using
compartment syndrome. ACS, abdominal compartment a pressure transducer after instillation of saline into
syndrome; IAP, intra-abdominal pressure; IAH, intra- the urinary bladder.
abdominal hypertension.
Items required for monitoring IAP (via urinary
bladder):
Table 10.1. Grades of intra-abdominal hypertension ● ● sedation for patient if needed and depending on
and abdominal compartment syndrome in human hemodynamic and pain status (butorphanol,
patients. Note that normal intra-abdominal pressures methadone, fentanyl, midazolam, dexmedetomi-
in dogs and cats are slightly higher than those reported dine);
in humans.
● ● sterile gloves;
Grade Pressure mmHg (cmH O) ● ● foley urinary catheter (or red rubber catheter
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in cats);
Grade I 12–15 (16–20) ● ● sterile lubricant for placing Foley urinary cathe-
Grade II 16–20 (21–27) ter (or red rubber catheter in cats);
Grade III 21–25 (28–33) ● ● urinary collection system;
● ● water manometer;
Grade IV >25 (>33) ● ● three-way stopcocks (2);
Abdominal compartment > 20 (27) sustained with ● ● 35–60 mL syringes;
syndrome new organ dysfunction ● ● 1-L bag of sterile saline or any other isotonic
or failure
crystalloid;

Manometer-based Monitoring 201