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 25-35 ml/kg/day

• Na+ 0.9-1.2 mmol /kg/day

• K+ 1 mmol/kg/day

Serum Values of Electrolytes

Cations Concentration, mEq/L

Sodium 135 - 145

Potassium 3.5 - 4.5

Calcium 4.0 - 5.5

Magnesium 1.5 - 2.5

Anions

Chloride 95 - 105

HCO3 22 - 27

Phosphate 2.5 - 4.5

Fluids available

G 5%

NS

Ringer’s

RL

No electrolytes,

50 g glucose / liter

Na Cl

154 154

Na Cl K Ca HCO3

147 156 4 4.5 0

Na Cl K Ca HCO3

130 109 4 3 28

• The same applies to colloids

CONCENTRATION AND

SOLVENT

MEAN MOLECULAR

WEIGHT

MOLAR

SUBSTITUTION

C2/C6

RATIO

MAXIMUM

DAILY DOSE

ml/kg

HES

200/0.5

6% SALINE

10% SALINE

200 0.5 5:1 33

20

HES

130/0.42

6% SALINE 130 0.42 6:1 50

HES

130/0.4

6% SALINE

10% SALINE

130 0.4 9:1 50

33

HES

130/0.4

6%BALANCED

SOLUTIONS130 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

• Maintenance 4 : 2 : 1 rule

• Deficit maintenance x h fasting

• Third space loss ??? 10 – 15 ml /kg/h

• Blood loss 3:1 by crystalloids

Fatal Postoperative Pulmonary Edema*

Pathogenesis and Literature ReviewAllen 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 ReviewAllen 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. 1-10 kg = 100 mL/kg/day {4mL/kg/hr}

2. 11-20 kg = 50 mL/kg/day {2mL/kg/hr}

3. > 21 kg = 20 mL/kg/day {1mL/kg/hr}

4. insensible loss = 700 mL/day or 0.2 cc/kg/day for every 1° C > 37°

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 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.

• 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.

Hausel et al. A carbohydrate-rich drink reduces preoperative discomfort in elective surgery patients. Anesth Analg. 2001;93:1344-1350

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 MetabCare. 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 PRE-

OPERATIVE 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.