Anesthesia Protocols
Authors: Dr. Gregory Sund, Dr. Matt Kynes
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Date: 15 October, 2020
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Revised: 12 December, 2023
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Next Revision: December 2026
Version 2. Changes from Version 1: Appendix 1, risk stratification of adverse cardiac outcomes was added. Appendix 2, risk calculator for adverse cardiac events was added.
Purpose: The peri-operative period is one of intense stress for many patients. Many patients coming to theater will be suffering from pain and/or anxiety in addition to their underlying condition. Surgery and anesthesia are always accompanied by varying degrees of risk, both of morbidity and mortality. There is much that we as healthcare practitioners can do to ease the fear and stress of our patients and to ensure their security. The following protocols are meant to maximize the safety of our patients who need surgical care. It is important to remember that the peri-operative period does not end when the patient leaves the theater. Many complications from surgery and anesthesia will not manifest until hours and sometimes days after surgery. Vigilance as well as compassion are both critical in our care of these patients for the glory of God.
Whenever consultation by the medical team regarding assessment of perioperative risk and patient optimization is requested, please inform the anesthesia team simultaneously. Patients having high-risk surgery (see appendix 1) or patients suspected of having severe or untreated disease (eg. uncontrolled hypertension, congestive heart failure, history of stroke) should be referred to pre-anesthesia clinic for elective surgical interventions prior to the day of surgery. The pre-anesthesia clinic is available for patient referral Monday through Friday from 8 AM to 4:30 PM. A final decision about whether a patient is ready to proceed with surgery will depend on input from the medical team, anesthesia team, and surgical team weighing the risks of surgery and anesthesia with their benefits.
Pre-operative Protocols
Lab work
Patients may require certain laboratory evaluations prior to undergoing surgery and anesthesia. These will be dependent on the patient’s underlying co-morbidities as well as the surgical intervention planned. The following are recommended:
a. Hemoglobin/Hematocrit should be measured within 48 hours of surgery for all patients who are suspected of being pre-operatively anemic (Hgb < 12 for women, < 13 for men) or for those surgeries where significant blood loss is anticipated (greater than 500 mL for adults and greater than 7 mL/kg for pediatrics). Additionally, all patients presenting for cleft lip or palate surgery should have a hemoglobin/hematocrit drawn the day BEFORE surgery.
b. Any patient who is critically ill or expected to have significant intra-operative blood loss or who is suspected of being severely anemic pre-operatively should have a GXM drawn at least the day prior to surgery.
c. Pregnant patients with pre-eclampsia should have a platelet count and hemoglobin drawn within 24 hours prior to surgery.
d. Potassium should be measured within 24 hours of surgery for patients requiring dialysis for renal insufficiency. Potassium should also be measured within 48 hours of surgery for patients receiving Furosemide.
e. All patients presenting for TURP should have electrolytes drawn prior to surgery. All patients with bowel obstruction should have pre-operative electrolytes drawn also, although this should not delay the onset of emergency surgery.
f. Coagulation studies (PT/PTT/INR) should be performed within 24 hours of surgery on patients requiring Warfarin.
g. All women of child-bearing age should be asked of the possibility of pregnancy. If there is a possibility that a woman may be pregnant, they should undergo pregnancy testing prior to elective surgery.
h. Other lab work may be required at the discretion of the surgical or anesthesia team. If there are any questions regarding pre-operative evaluation, please contact these teams as early as possible before the planned intervention.
Cardiac evaluation
Patient with known or suspected cardiac disease will need to be evaluated by the senior anesthetist prior to surgery. Please notify the anesthesia team of these patients no later than the day prior to surgery. If there is suspicion of poorly controlled heart disease, the anesthesia team may require the patient undergo further evaluation (ECG or echocardiogram) prior to coming to theater. The anesthesia team should be notified of any patient requiring surgery who has a pacemaker/defibrillator, no later than the day before surgery. The following patients should undergo ECG evaluation within 1 week prior to undergoing an intermediate or high-risk surgery (see examples of low, intermediate and high-risk surgeries in Appendix 1).
a. any patient with a history of MI and/or CHF
b. any patient with a history of arrhythmias
c. any patient having symptoms of chest pain or shortness of breath on exertion
d. any patient greater than 65 having intermediate or high-risk surgery with 2 or more of the following risk factors (DM, HTN, renal insufficiency, hyperlipidemia)
Any patient with known or suspected structural heart disease or any patient with unexplained dyspnea on exertion, chest pain, syncope, or unexplained murmurs should undergo an echocardiogram prior to surgery.
The risk for a patient of having a major cardiac event in the perioperative period can be estimated using the Revised Cardiac Risk Index (see Appendix 2).
NPO guidelines
Patients requiring elective surgery should be NPO (nil per os) according to the following guidelines (minimum fasting period expressed in hours before surgery):
Adults
| Liquid and Food Intake | Minimum Fast Period (hours) |
|---|---|
| Clear liquids | 2 |
| Milk or light meal | 6 |
| Heavy meal | 8 |
Children
| Liquid and Food Intake | Minimum Fast Period (hours) |
|---|---|
| Clear liquids | 0 |
| Breast milk | 3 |
| Formula or nonhuman milk | 4 |
| Light meal | 6 |
| Heavy meal | 8 |
Patients having urgent or emergent surgery may require surgery sooner than recommended by these guidelines. In these cases, the decision to proceed with such surgery should be based on direct communication between the consultant surgeon and the senior anesthetist involved in the surgery.
Fluid guidelines
While patients are fasting, they may require intravenous fluids to maintain homeostasis in the pre-operative period. Infants and neonates are especially vulnerable to the effects of hypovolemia and hypoglycemia from prolonged fasting periods. Therefore, infants and neonates should be scheduled for surgery as early as possible in the morning to minimize fasting times (3 hours for breastfeeding and 1 hour for clear liquids). Unless contraindicated, all patients should be permitted and encouraged to drink clear liquids up until 2 hours before the start of surgery. The following recommendations regarding maintenance fluids should be followed:
Adults: if an IV is in place and the patient cannot take clear liquids up until 2 hours before surgery, the patient should receive maintenance fluids using a balanced crystalloid, such as Normal Saline. If a prolonged fasting period (greater than 8 hours) is anticipated, an IV should be placed pre-operatively in order to start maintenance fluids.
Pediatrics (older than 1 year): if an IV is present the patient should receive maintenance fluids using D5NS (see chart below). If a prolonged fasting period (greater than 8 hours) is anticipated, an IV should be placed pre-operatively in order to start maintenance fluids.
Infants (1 month to 1 year): if an IV is present the patient should receive maintenance fluids using 1/2 D10 + 1/2 NS (see chart below). If a prolonged fasting period (greater than 3 hours for breastfeeding infants) is anticipated, an IV should be placed pre-operatively in order to start maintenance fluids.
Neonates (less than 1 month): an IV SHOULD be placed on all neonates who are NPO, and maintenance fluids should be started using 4/5 D10 + 1/5 NS (see chart below).
PEDIATRIC ANESTHESIA IVF AT KIJABE HOSPITAL
Routine intraoperative neonatal fluids (0-28 days)
| Fluid Plan | How to Mix | Usual Rate/Amount |
|---|---|---|
| 1) D10 NS – maintenance. 2) NS or LR – bolus | 1) D10 NS. For syringe pump (preferred): mix 48mL of NS + 12mL D50 = D10 NS. For burette: mix 4mL/kg NS + 1mL/kg D50 = D10 NS. 2) NS or LR Given through a separate line | 1) D10 NS = maintenance. 3-4mL/kg/hr. 2) NS or LR. Replace blood loss (3mL to 1mL), evaporative losses (2-8mL/kg/hr depending on incision) |
Routine intraoperative pediatric fluids (1mo – 12yo)
| Fluid Plan | How to Mix | Usual Rate/Amount |
|---|---|---|
| NS | 0.9% NS | 10-20mL/kg bolus as needed. Maintenance: 4-2-1 rule. Evaporative loss: 2-8mL/kg/h. Blood loss: 3mL to 1mL |
Intraoperative pediatric fluids – hypoglycemia risk (malnourished, NPO >12 hours, liver dysfunction)
| Fluid Plan | How to Mix | Usual Rate/Amount |
|---|---|---|
| 1) D10 NS – maintenance. 2) NS or LR – bolus | 1) D10 NS. For syringe pump (preferred): mix 48mL of NS + 12mL D50 = D10 NS. For burette: mix 4mL/kg NS + 1mL/kg D50 = D10 NS. 2) NS or LR. Given through a separate line | 11) D10 NS = maintenance. 4-2-1 Rule. 2) NS or LR. Replace blood loss (3mL to 1mL), evaporative losses (2-8mL/kg/hr depending on incision) |
Child in shock/arrest
| Fluid Plan | How to Mix | Usual Rate/Amount |
|---|---|---|
| NS Bolus | 0.9% NS | Well-nourished: 20mL/kg as needed. Malnourished septic shock: 5-10mL/kg x3 then start epinephrine gtt |
Child with hypoglycemia
| Fluid Plan | How to Mix | Usual Rate/Amount |
|---|---|---|
| D10% bolus | Neonate: 0.5mL/kg D50 + 2mL/kg sterile water. Infant/child: 1mL/kg D50 + 4mL/kg sterile water | Neonate: 2.5mL/kg D10% and recheck, possible infusion. Infant/child: 5mL/kg D10% and recheck, possible infusion |
Anticoagulation
Patients receiving pre-operative anticoagulation may be at increased risk of peri-operative complications. The use of certain anticoagulants may also preclude the use of regional anesthesia. In general, the following guidelines should be followed:
Enoxaperin: Patients receiving enoxaperin prophylaxis (one dose per day) should have this medication held the morning of surgery and at least 12 hours before placement of a neuraxial anesthetic. In cases where an epidural catheter is placed for post-operative analgesia, Enoxaperin can be safely used, however the first dose of Enoxaperin SC after epidural placement should be delayed at least 12 hours from the time of catheter placement while the last dose should be given at least 12 hours before. After catheter removal, Enoxaperin can be restarted after 4 hours.
Heparin: Patients receiving low-dose heparin prophylaxis (SC BID or TID) should have this medication held the morning of surgery, and at least 4-6 hours before the placement of a neuraxial anesthetic. Patients receiving intravenous heparin infusions should have this medication held at least 4-6 hours AND have verification of normal coagulation status before placement of neuraxial anesthesia. In cases where an epidural catheter is placed for post-operative analgesia, heparin infusions should be delayed at least 1 hour from the time of catheter removal. Low-dose SC Heparin can be re-started anytime after catheter removal.
Warfarin: Patients receiving Warfarin should have this medication held, ideally, 5 days prior to surgery and will need to have had an INR equal or less than 1.4 before receiving neuraxial anesthesia (spinal or epidural). This medication may be restarted anytime after spinal anesthesia or removal of an epidural catheter.
Rivaroxaban: Patients receiving Rivaroxaban should have this medication held at least 72 hours prior to spinal or epidural anesthesia. This medication can be restarted 6 hours after spinal anesthesia or single-short epidural injection but should NOT be used in the presence of an indwelling epidural catheter.
Other anticoagulants: The senior anesthetist should be notified the day BEFORE surgery of any patients receiving any other anticoagulant for recommendations regarding the timing of discontinuation. Recommendations regarding these medications can be found on the following website: ASRA Guidelines.
Blood pressure management
Patients with uncontrolled hypertension are at increased risk of peri-operative complications. Every effort should be made to control blood pressure prior to elective surgery. Patients who present to theater with uncontrolled hypertension are likely to be postponed by the anesthesia team. For most elective cases, a diastolic blood pressure greater than 110 mmHg or a systolic blood pressure greater than 180 mmHg will result in the surgery being postponed until the hypertension is controlled.
It is important that patients receiving anti-hypertensive medications receive these medications up until and including the morning of surgery with a sip of water. The surgery team will need to arrange for early administration of these medications with the nursing team for first-case surgeries of the day. The exceptions to this rule are ACE-inhibitors and Angiotensin Receptor Blockers, which in some circumstances should be withheld for 24 hours before elective surgery.
Intra-operative protocols
Intra-operative anesthesia will be performed at the discretion of the anesthesia team. Communication between surgical, anesthesia and OR nursing teams is critical in maintaining patient safety during the peri-operative period. For critically ill patients, especially those who are anticipated to need post-operative ventilatory support, the availability of an ICU bed with a ventilator should be confirmed before the start of surgery. In addition, the senior anesthetist should communicate directly with the ICU consultant as early as possible during the intervention to allow the ICU team time to prepare for the patient’s arrival. Any patients remaining intubated post-operatively will bypass the PACU and proceed directly to the ICU, accompanied by the senior anesthetist.
Post-operative protocols
With the exception of those patients needing post-operative ventilatory support, or patients who are unstable and will need monitoring in the ICU/HDU, all patients will proceed to the Post-Anesthesia Care Unit (PACU) until it has been verified that the patient is stable from a hemodynamic and respiratory standpoint, and that they have recovered sufficiently according to our recovery room guidelines.
After transfer of the patient from the PACU, the receiving nurse should evaluate the patient and record vital signs within 1 hour of their arrival. The level of pain should also be assessed regularly in the post-operative period and if there are any concerns about post-operative pain management, the surgical team or the anesthesia team should be contacted.
For patients in whom an epidural catheter is left post-operatively, this should ONLY be manipulated by or injected by a member of the anesthesia team. Discontinuation of the epidural catheter will be at the discretion of the anesthesia team and this will be communicated directly to both the nursing team as well as the surgical team.