Volume 6, Spring 2008 - Saddleback College

Fall 2007 Biology 3A Abstracts
patient under anesthesia is monitored by external
diagnostic parameters. Utilizing external monitoring
equipment in addition to peripheral palpation,
clinicians and veterinary nurses observe the continuous
status of the patients pulse rate, respiration rate,
Saturation of Peripheral oxygen (SPO 2) and body
temperature. Other important parameters include
Electro-Cardiogram (ECG), Systolic (SBP), Diastolic
(DBP), and Mean Arterial blood Pressures (MAP) as
well as End-Tidal carbon dioxide (ETCO 2 ) levels.
Lactate has also been established as a valuable test in
the vast diagnostic repertoire of clinicians (Pang &
Boysen 2007). However, the use of serial lactate
monitoring in veterinary medicine during anesthetic
procedures, is not common practice despite the recent
increase of its use in human medicine and the
convenience of handheld portable devices that are now
available.
Elevated blood lactate levels are typically
associated with hypo-perfusion; that is the decrease in
the process of nutritive delivery of arterial blood to
capillary beds in biological tissue, when pyruvate is
unable to enter the Krebs cycle as the cellular oxygen
supply is insufficient (Pang and Boysen, 2007). This
experiment focused on the change in lactate levels over
time in canines undergoing elective, minimally
invasive, lower abdominal anesthetic procedures. Prior
observations in anesthetic research support evidence
indicative of anesthesia having a significant effect on
the decrease of systemic perfusion (hypo-perfusion)
(Pang and Boysen, 2007).
A previous study conducted at Lokmanya
Tilak Municipal Medical College and Hospital, by
Shinde et al. (2005), intended to establish serial blood
lactate levels as a prognostic tool, in human patients
receiving valvular heart surgery and undergoing cardio
pulmonary bypass (CPB) during the procedure. The
parameters that were evaluated were lactate levels and
its correlation with preoperative clinical condition and
the intra and postoperative outcomes, following CPB
for valvular heart surgery. They concluded that there
was a significant increase in lactate during CPB from
0.8 as a baseline to the intraoperative level of 7.0 +/-
2.3, also noting a decrease post operatively during rewarming
of the patient immediately following CPB
(Shinde et al., 2005). This raises the question of the
necessity of serial lactate testing during anesthesia
while setting precedence for further research as to the
potential merit of the common use of serial lactate
testing in veterinary medicine.
Blood lactate is a dynamic balance involving
production and clearance (Pang and Boysen, 2007).
Production of blood lactate exists in low levels of
concentration under normal conditions of aerobic
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Saddleback Journal of Biology
Spring 2008
metabolism, in canines this level is considered normal
when it is less than 2.5mmol/L. Ideally, with normal
healthy individuals, lactate clearance is optimally
maintained by the liver and kidneys. However, an
imbalance in metabolic function, stress from surgery,
and other conditions can alter this balance (Evans,
1987).
When the metabolic balance is disturbed, a
condition known as hyperlactatemia (lactate levels
>2.5mmol/L and