FLUID & NURITION THERAPY – PATIENT OUTCOME Waleed Hamimy Professor of Anesthesia, SICU & Pain Management Cairo University
Introduction • Fluid therapy is fundamental to the practice of
ANESTHESIA, but the precise type, amount, & timing of its administration is still the subject of extensive debate • This necessitates good understanding of normal
& abnormal physiology & the requirements for patients under different circumstances
Introduction • Lack of knowledge is a cause of morbidity &
mortality due to fluid imbalance • The fluid & electrolyte content is of vital importance
Importance of Fluid Therapy • Maintain blood volume • Avoid inadequate perfusion • Avoid electrolyte disturbances & dehydration
Errors in fluid management is the most common cause of morbidity & mortality
1999
The right fluid in the right amount for the right patient at the right time
Type of fluid
Why do we give fluids?
To Maintain
To Replace
different fluids, along with their carrier solutions are drugs with different effects.
To Maintain • We should know the normal daily requirements of
water & electrolytes • Water • Na+ • K+
25-35 ml/kg/day 0.9-1.2 mmol /kg/day 1 mmol/kg/day
Serum Values of Electrolytes Cations Sodium Potassium Calcium Magnesium
Concentration, mEq/L 135 - 145 3.5 - 4.5 4.0 - 5.5 1.5 - 2.5
Anions Chloride HCO3 Phosphate
95 - 105 22 - 27 2.5 - 4.5
Fluids available
G 5%
No electrolytes, 50 g glucose / liter
NS
Na 154
Cl 154
Ringer’s
Na 147
Cl 156
K 4
Ca 4.5
HCO3 0
RL
Na 130
Cl 109
K 4
Ca 3
HCO3 28
• The same applies to colloids
HES 200/0.5
CONCENTRATION AND SOLVENT
MEAN MOLECULAR WEIGHT
MOLAR SUBSTITUTION
C2/C6 RATIO
MAXIMUM DAILY DOSE ml/kg
6% SALINE
200
0.5
5:1
33
10% SALINE
20
HES 130/0.42
6% SALINE
130
0.42
6:1
50
HES 130/0.4
6% SALINE
130
0.4
9:1
50
10% SALINE
HES 130/0.4
6%BALANCED SOLUTIONS
33
130
0.4
9:1
50
Amount of fluids
We are used to give excess fluids!!!! • The following were considered: • Preoperative fasting • Losses • Surgical blood loss
• Evaporation • Urine output
• VD caused by spinal or epidural anesthesia • Transfer to the third space
• Trans-capillary leak of albumin caused by injury
Fluid shifting • 1st space shifting- normal distribution of fluid in both the ECF compartment & ICF compartment. • 2nd space shifting- excess accumulation of interstitial
fluid (edema) • 3rd space shifting- fluid accumulation in areas that
normally have no or little amounts of fluids (ascites)
There was always an overestimation of the total fluids required 4 : 2 : 1 rule • Deficit maintenance x h fasting • Third space loss ??? 10 – 15 ml /kg/h • Blood loss 3:1 by crystalloids • Maintenance
Fatal Postoperative Pulmonary Edema* Pathogenesis and Literature Review Allen I. Arieff, MD • Retrospective analysis of 13 patients with fatal
pulmonary edema. • Ten were generally healthy while three having serious associated
medical conditions.
Fatal Postoperative Pulmonary Edema* Pathogenesis and Literature Review Allen I. Arieff, MD •
Conclusions: • Pulmonary edema can occur within the initial 36 postoperative
hours when net fluid retention exceeds 67 mL/kg/d. • There are no known predictive warning signs & cardiorespiratory arrest is the most frequent clinical presentation.
British Journal of Surgery 2009; 96: 331–341
CONCLUSION: Perioperative outcomes favored a GD therapy rather than liberal fluid therapy without hemodynamic goals. Whether GD therapy is superior to a restrictive fluid strategy remains uncertain.
Even in the postoperative period
Conclusions: The use of a restrictive postoperative fluid protocol significantly reduces the duration of hospital stay in patients who have undergone major elective abdominal vascular surgery.
Normal Maintenance Requirements For Water it is typically 35 mL/kg/day 1. 2. 3. 4.
1-10 kg = 100 mL/kg/day {4mL/kg/hr} 11-20 kg = 50 mL/kg/day {2mL/kg/hr} > 21 kg = 20 mL/kg/day {1mL/kg/hr} insensible loss = 700 mL/day or 0.2 cc/kg/day for every 1째 C > 37째
Simply, hourly maintenance = 40 + weight (kg)
Metabolic response to fasting • metabolic rate substrate oxidation
accelerated catabolism (breakdown of glycogen, fat & protein).
Metabolic response to fasting • Insulin levels are often increased but blood
glucose levels also increase due to the developed insulin resistance. • The insulin/glucagon ratio is reduced, resulting in an
increased gluconeogenesis • Conventional preoperative fasting time may
aggravate insulin resistance hyperglycemia
Metabolic response to fasting • Additionally, overnight fasting ďƒ variable
degrees of dehydration depending on the duration of the fasting period
Benefits of less fasting hours • Reduction of preoperative fasting time seems to have a
beneficial effect on peri-operative thirst, hunger, anxiety & muscle strength. Hausel et al. A carbohydrate-rich drink reduces preoperative discomfort in elective surgery patients. Anesth Analg. 2001;93:1344-1350
• Patients undergoing elective cardiac surgery treated with
the same preoperative fasting protocol were less thirsty compared with controls & required less intraoperative inotropic support after initiation of CPB weaning. Breuer et al. Preoperative oral carbohydrate administration to ASA III-IV patients undergoing elective cardiac surgery. Anesth Analg. 2006;103:1099-1108.
New recommendation • Intake of clear fluids until 2 h before surgery &
anesthesia. • ESPEN recommended, a carbohydrate-rich drink 2 h
before anesthesia (grade A evidence) 1.
Noblett et al. Pre-operative oral carbohydrate loading in colorectal surgery: a randomized controlled trial. Colorectal Dis.
Sep 2006;8(7):563-569. 2.
Nygren J, Thorell A, Ljungqvist O. Preoperative oral carbohydrate nutrition: an update. Curr Opin Clin Nutr Metab Care. Jul 2001;4(4):255-259.
Are these recommendation applied? • CURRENT KNOWLEDGE, PRACTICE AND ATTITUDE
OF PREOPERATIVE FASTING: A LIMITED SURVEY AMONG UPPER EGYPT ANESTHETISTS • ossama Hamdy; Salah M Asseda; Hatem S Ali,
• South valley University
• showed that the majority (72%) of studied Anesthetists
are aware of the new preoperative fasting guidelines; however, they are still practicing strict preoperative NPO from midnight. Only 10% follow the new guidelines. EgJA 2013
HAS THE IMPLEMENTATION OF THE CURRENT PREOPERATIVE FASTING GUIDELINES (UK GIFTASUP) BEEN SUCCESSFUL? AN AUDIT OF CURRENT PRACTICE
Thomas Hall, James Stephenson, Cristina Pollard, Ashley Dennison. Int. J. Surgery (2012)
• Methods: • A prospective audit of all surgical patients undergoing a general surgical procedure requiring a general anesthetic using a structured questionnaire over a 20 day period was performed • Results: • 75 patients were followed through the perioperative period with 41 elective and 34 emergency cases. The average pre-operative NBM period for clear liquids was 14 and 19 hours in the elective group and emergency group respectively. Zero patients in the elective group had clear fluids 2 hours prior to induction of anesthesia and 2 (5%) patients in this group had clear fluids between 2 & 6 hours prior to anesthesia.
• Conclusion: • The results demonstrate that adherence to the guidelines is poor. With the advent of enhanced recovery programs and an emphasis on early enteral feeding post-operatively to maintain ‘normal' physiology we appear to have forgotten about the pre-operative period. Education about the guidelines is desperately needed.