神經性（中心性）尿崩症常用工具
（Neurogenic
(Central) Diabetes Insipitus）
l Definition:
Criteria of Enrollment
(1) urine output ≧ 11/2 times the calculated maintenance fluid intake for 2 consecutive hr.
(2) urine specific gravity ≦ 1.005 (and urine osmolality ≦ 300 mOsm/kg H2O if measured.
(3) a plasma Na level ≧ 150 mmol/L (and serum osmolality ≧ 310 mOsm/kg H2O if measured) ( Na>149 for patients with operation at the suprasellar or sellar area [Chansen87]),
(4) a concurrent low AVP level and observed response to exogenous AVP or DDAVP treatment,
(5) no diuretics in use over the preceding 12 hours, and
(6) normal renal function and normal serum K, Ca. [Bilsky93, Fiser87, Outwater84]
l Clinical features:
多尿（polyuria）, 多喝（polydipsia）,夜尿或尿床,喜喝冰水或甜的飲料,皮膚乾燥、蒼白、不易流汗; 若病灶在下視丘，可能會有生長遲緩、逐漸肥胖或消瘦、發燒、睡眠困難、性早熟或情緒障礙; 視覺障礙, 抽搐：常是高血鈉所致
鑑別診斷
多尿與多喝（Polyuria and polydipsia）、腎性尿崩症（nephrogenic DI）則為抗利尿激素在標靶器官缺乏作用所致，好發於男嬰。糖尿病、高血鈣、低血鉀。
原發性多喝（飲）症（primary polydipsia）：常見於精神病病人。乃因口渴機轉（thirst mechanism）異常所致。只要不給水喝，尿就逐漸濃縮。
尿濃縮上的缺陷（Defects in urinary concentrations, Isotonic urine），為患慢性腎病（chronic renal disorders）或家族性腎癆病（familial nephronophthisis）的病人，此時其BUN和 creatinine上升，且有貧血現象。
l Routine
diagnostic procedures:
Urine volume, Specific gravity, glucose qh
Na, K, Ca (micro) st and q2h
Glucose by glucometer q6h
Body height
Body weight qd
Check serum Glucose, Creatinine, osmolality,
Check urine osmolality, Na, Cr
Check serum ADH (聯絡核醫分機2626)
IV fluid 分為 Line A, Line B, Line C:
Line A: Normal saline (每100ml 加 2 ml KCl ) iv. ml qd (200-400 ml/m2)以補充insensible water loss
Line B: D5W (若Na > 140) 或 D51/4 NS(即每100ml由75ml D5W及25ml D5S組成)(若Na < 140) run urine output qh
Nasal DDAVP 1 puff q8h prn if urine output ≧ 11/2 times the calculated maintenance fluid intake for 2 consecutive hr
請儘量維持尿量在 ml/hr(65 ml/100 kcalmetabolized/day)。(請通知醫師調整vasopressin量)
l Comment:
*Fluid input:
Urine output replacement: D5W or D5 1/4 NS for Na >140 or <140 respectively, qh
Insensible water loss & basal requirement of electrolyted: NS plus KCl 40 mEq/L at 400 ml/m2/24hr, corrected for fever and humidity in the inhaled air, qd
Extra-renal loss: q8-24hr
GI loss with NS plus Kcl q8h
CSF loss with NS q8h
* The calculation of the water deficit is done as follow
Water deficit = [0.6×body weight (kg)]×[current pNa+/140 －1]
For example, in a normal 70-kg patient who is normotensive with a plasma sodium level of 160, the free water deficit would be estimated to be:
(0.6×70 kg)(160/140-1) = 5.9 kg (L) of water
Monitoring
I/O qh
Urine volume, Sp Gr, glucose qh
Na, K, Ca q6h
Glucose q6-24h
Weight qd
References
Bilsky M. In: Neurological and Neurosurgical Intensive Care. 3rd ed. 1993;323
Chanson P. Critic Care Med 1987;15:44-6
Fiser D, Crit Care Med 1987; 15:551-553
Outwater KM, Neurology 1984;34:1243-1246.
Robson AM. In: Nelson Textbook of Pediatrics, 14ed, 1992; 195-214
Weigle CGM. In: Textbook of Pediatric Intensive Care. 2nd ed 1992; 1250-2.
Hill JH: SIADH, cerebral salt wasting, and central diabetes insipidus. In: Blumer JL, eds. A practical guide to pediatric intensive care. 3rd ed. St.Louis: Mosby-Year Book. 1990: 541-5.