Abstracts
2000 Digestive Disease Week

# 2314 Hyperamylasemia in Neurosurgical Patients.
Katherine J. M. Liu, Mary Jo Atten, Debra Hawkins, Evageline Panizales, Moon Ja Cho, Terry Lichtor, James Stone, Philip E. Donahue, Chicago, IL

Hyperamylasemia of pancreatic origin has been observed in neurosurgical patients in the absence of clinical pancreatitis. However, the clinical conditions associated with this hyperamylasemia are unclear. Hence, we evaluated these neurosurgical patients to identify the clinical significance of pancreatic enzyme elevations in neurosurgical patients. Methods and Results: We retrospectively reviewed the charts of patients who were admitted to Cook County Hospital Neurosurgical ICU over a 4 month period. Seventy-four consecutively admitted patients were divided into two groups: Group I (n=63) had normal serum amylase and lipase levels throughout the entire hospitalization, and Group II (n=11) had both serum amylase and lipase elevations at some point during the hospitalization. Twenty-three of the Group I (36%), and 10 of the Group II (91%) patients underwent craniotomy (p<0.001). Ten of the Group I (16%), and 7 of the Group II (64%) patients required craniotomy for intracranial bleeding (p<0.01). In Group II patients, mean serum amylase levels were 402 ± 444 U/L (Mean ± SD), range of 106-1743 (nl£75), and lipase levels were 474 ± 313 I.U. (Mean ± SD), range of 176-1385 (nl£55). On average, serum amylase and lipase elevations were noted on the 9th day post-craniotomy (range 5-18 days), and both enzymes peaked on the same day in 8 of the 11 patients (73%), unlike the delayed peak of serum lipase seen in patients with true pancreatic inflammation. No clinical or radiographic evidence of pancreatitis was otherwise found. Medications, as well as feeding routes and formulations, were similar in the two groups. Conclusions: The severity of the intracranial event and need for craniotomy appear to be the most important factors associated with serum amylase and lipase elevations, particularly in the case of intracranial bleeding requiring craniotomy and clot evacuation. Increased vagal activity, altered sympathetic adrenergic tone, hormonal stimulation, and/or release of cytokines are possible mechanisms for the pancreatic enzyme elevation. The elevated serum amylase and lipase do not appear to be associated with any pathological process in the pancreas. Therefore, extensive work-up, creating significant costs and undue delays in enteral nutrition, is not warranted in these patients.