PACU nursing: Aldrete score, discharge criteria, and 20 NCLEX tips

The post-anesthesia care unit (PACU) is where surgical patients spend the first critical hours after general, regional, or monitored anesthesia care. During this window, anesthetic agents are metabolizing, physiologic reflexes are returning, and the risk of airway obstruction, respiratory depression, cardiovascular instability, and pain crisis is highest. PACU nursing is both high-acuity monitoring and rapid clinical decision-making – typically one nurse to one or two patients, with no physician routinely at the bedside.

The nurse’s job is to keep the patient safe while the body transitions out of anesthesia, manage complications before they escalate, and discharge the patient only when objective scoring criteria confirm readiness. The Aldrete score drives Phase I discharge; the Post-Anesthetic Discharge Scoring System (PADSS) drives home readiness after ambulatory surgery.

Quick-reference: The five Aldrete score domains are activity, respiration, circulation, consciousness, and SpO2. Each scores 0–2. A total of ≥9 clears Phase I discharge per most institutions (some accept ≥8 with physician order).

What is the PACU?

The post-anesthesia care unit – also called the recovery room – provides close monitoring and nursing intervention during the emergence phase of anesthesia. Emergence is not instantaneous; depending on the agent used, anesthetic depth, duration of surgery, and patient metabolism, full return of protective reflexes and consciousness can take minutes to hours.

The American Society of Anesthesiologists (ASA) Standards for Post-Anesthesia Care require that all patients receiving general, regional, or monitored anesthesia care be admitted to a PACU or an equivalent area. Perianesthesia nursing standards are published by the American Society of PeriAnesthesia Nurses (ASPAN) and updated biennially.

Phase I vs. Phase II recovery

PACU care is divided into two distinct phases with different staffing ratios, monitoring intensity, and discharge goals:

Patients admitted directly from the OR who require ICU-level care bypass Phase II entirely. Patients undergoing short ambulatory procedures under minimal sedation may skip Phase I and enter Phase II directly – a practice called “fast-tracking.”

Who is admitted to the PACU?

Any patient who has received general anesthesia, neuraxial anesthesia (spinal or epidural), deep sedation, or monitored anesthesia care. Patients who had local-only infiltration without sedation generally do not require PACU admission.

Aldrete score: objective discharge criteria

The Modified Aldrete Postanesthesia Recovery Score was introduced by Dr. Juan Aldrete in 1970 and revised in 1995. The 1995 revision replaced the original color criterion – a subjective visual judgment of skin appearance as a proxy for oxygenation – with objective pulse oximetry. The circulation (blood pressure) domain was retained in both versions. It remains the most widely used Phase I discharge tool in the world.

Discharge threshold: Most institutions require a total Aldrete score of ≥9 out of 10 for Phase I discharge. Some accept ≥8 with an attending physician order.

PADSS for ambulatory surgery

For patients going home after day surgery, the Post-Anesthetic Discharge Scoring System (Chung, 1995) adds parameters relevant to home readiness. Each criterion scores 0–2; a total of ≥9 is required for home discharge, and vital signs must score 2 (cannot be the weakest link):

• Vital signs – within 20% of preoperative baseline (2), 20–40% deviation (1), >40% deviation (0)
• Ambulation – steady gait, no dizziness (2), assisted ambulation (1), unable (0)
• Nausea/vomiting – minimal or controlled orally (2), moderate with IV treatment (1), severe despite treatment (0)
• Pain – controlled with oral analgesics and acceptable to patient (2), moderate but manageable (1), severe (0)
• Surgical bleeding – minimal or none (2), moderate with dressing changes (1), severe with major dressing changes (0)

PACU admission assessment

Anesthesiologist handoff

The anesthesiologist accompanies the patient to the PACU and gives a structured verbal handoff before leaving. PACU nurses should use SBAR (Situation–Background–Assessment–Recommendation) as a framework for receiving and confirming this information. Handoff communication is a Joint Commission accreditation requirement. It sits in the Provision of Care chapter as standard PC.02.02.01, EP 2, which requires the handoff process to provide an opportunity for discussion between the giver and the receiver of the information. (It was formerly National Patient Safety Goal 02.05.01; the Joint Commission converted it from a goal to a standard in 2010, so citing it as an NPSG is out of date.) A read-back or otherwise interactive exchange satisfies this; a one-way verbal dump does not.

Key elements of the handoff:

• S: Patient name, age, procedure performed, anesthetic type and agents
• B: Medical history, allergies, baseline vital signs, airway difficulty, aspiration risk
• A: Intraoperative events – blood loss, fluid administered, medications given (including reversal agents), regional blocks placed
• R: Current concerns – ongoing bleeding, pain level, antiemetic given, specific monitoring instructions

For structured handoff documentation skills, see the shift report and handoff nursing guide.

The 15-minute admission window

ASPAN standards specify that the first assessment begins immediately on admission and is completed within 15 minutes. During this window:

1. Connect the patient to continuous cardiac monitoring and pulse oximetry
2. Apply BP cuff and obtain baseline vital signs
3. Assess level of consciousness (Glasgow Coma Scale, responsiveness to voice)
4. Assess airway patency and respiratory effort – look, listen, feel
5. Inspect surgical site – dressing integrity, drainage, bleeding
6. Assess IV access – site, patency, current infusion rate and fluid type
7. Assess pain and nausea using validated scales
8. Confirm positioning requirements (e.g., post-mastectomy arm position, post-spinal head elevation)
9. Review medications – analgesics, antiemetics, reversal agents given intraoperatively
10. Confirm identity band and allergy band

Vital signs are then recorded every 5 minutes for the first 15 minutes, then every 15 minutes once stable, and documented per institutional policy. For normal vital sign ranges across age groups, see the vital signs by age reference.

Airway management post-anesthesia

Airway complications account for a significant proportion of PACU adverse events. Residual anesthetic effect, opioid administration, and incomplete neuromuscular reversal all impair airway muscle tone and respiratory drive.

Airway obstruction

The most common cause is the tongue falling back against the posterior pharynx as muscle tone is lost – particularly in patients with obesity, large neck circumference, or obstructive sleep apnea. Initial management:

• Chin lift / jaw thrust – reposition the mandible to lift the tongue off the posterior pharynx. Jaw thrust is preferred in patients with possible cervical spine injury.
• Oral or nasopharyngeal airway adjunct – if repositioning alone is insufficient. Insert oral airway only if the patient tolerates it without gagging (protective reflex absent). For technique detail, see the airway management nursing guide.
• Lateral positioning – if vomiting or secretions are present, turn patient to the left lateral (recovery) position to reduce aspiration risk.

Laryngospasm

Laryngospasm is forceful, involuntary adduction of the vocal cords. It is a medical emergency. Partial laryngospasm produces inspiratory stridor; complete laryngospasm produces a silent chest with paradoxical chest movement and rapidly falling SpO2.

Management sequence:

1. Remove the stimulus (suction secretions, remove airway adjunct)
2. Jaw thrust with firm continuous positive pressure via face mask – this mechanical pressure can break partial laryngospasm
3. 100% O2 via tight-fitting mask
4. If SpO2 continues to fall: succinylcholine 0.1–0.5 mg/kg IV to break complete laryngospasm (if there is no IV access, the label allows intramuscular dosing of up to 3–4 mg/kg)
5. Call for anesthesia backup immediately

Bronchospasm

Post-extubation bronchospasm presents with expiratory wheezing, increased peak airway pressure, and declining SpO2. It is more common in patients with asthma, COPD, or recent upper respiratory infection.

Management:

• Albuterol via nebulizer or metered-dose inhaler with spacer
• Heliox (helium-oxygen mixture 70:30) decreases airflow turbulence and reduces work of breathing while bronchodilators take effect
• Notify anesthesia provider

Residual neuromuscular blockade

Non-depolarizing neuromuscular blocking agents (rocuronium, vecuronium, cisatracurium) may not be fully reversed at emergence. Signs include:

• Unable to lift head for 5 seconds
• Weak hand grip
• SpO2 decline despite patent airway
• Shallow, ineffective respiratory effort

Reversal:

• Sugammadex – selective reversal of rocuronium and vecuronium. Label doses: 2 mg/kg once the second twitch of the train-of-four has reappeared, 4 mg/kg for deeper block (1–2 post-tetanic counts, no TOF response), and 16 mg/kg (rocuronium only) for immediate reversal about 3 minutes after a 1.2 mg/kg dose. Rapid onset, no muscarinic side effects.
• Neostigmine + glycopyrrolate – acetylcholinesterase inhibitor for reversal of any non-depolarizing agent. Dose: neostigmine 0.03–0.07 mg/kg (maximum 0.07 mg/kg or 5 mg, whichever is less) + glycopyrrolate 0.2 mg per 1 mg neostigmine (glycopyrrolate blocks muscarinic effects of neostigmine: bradycardia, bronchospasm, excessive secretions).

Respiratory monitoring

SpO2 targets and supplemental oxygen

Many post-anesthesia patients receive supplemental oxygen by nasal cannula while residual anesthetic and opioid effects wear off. The British Thoracic Society (BTS) 2017 oxygen guideline (section 8.15) sets the targets for surgical patients:

• SpO2 94–98% for most surgical patients
• SpO2 88–92% for patients at risk of hypercapnic respiratory failure, such as those with COPD, morbid obesity or obesity hypoventilation, or chest wall or neuromuscular disease

Older teaching says the lower COPD target exists to “preserve hypoxic drive.” BTS (section 6.3.1) ranks reduced ventilatory drive second among the mechanisms of oxygen-induced hypercapnia, behind worsening V/Q mismatch, and ahead of the Haldane effect and absorption atelectasis. The target range is what matters at the bedside. Never withhold oxygen from a hypoxemic patient, and step oxygen down gradually rather than stopping it abruptly.

Supplemental oxygen has a cost in this setting: it can mask hypoventilation. A patient with opioid-induced respiratory depression can keep a normal SpO2 on oxygen while PaCO2 climbs, and BTS cites evidence that hyperoxia adds to opioid-induced respiratory depression. Track respiratory rate, sedation level, and capnography where available, rather than relying on SpO2 alone.

Weaning O2 is appropriate once:

• The patient is fully awake and following commands
• SpO2 stays within the patient’s target range on room air
• Respiratory rate is 12–20 and effort is unlabored

For the physiology of oxygen delivery systems and flow rates, see the oxygen therapy nursing guide.

Respiratory rate and effort

Monitor respiratory rate every 5 minutes in the first phase. Rates below 10 (bradypnea) or above 24 (tachypnea) require immediate investigation. Assess respiratory effort – paradoxical breathing, use of accessory muscles, nasal flaring, and tripod positioning all signal distress.

Hypoventilation from opioids

Opioid-induced respiratory depression (OIRD) is one of the most dangerous, and most preventable, post-anesthesia complications. Signs include: respiratory rate <10, SpO2 falling despite supplemental O2, decreased level of consciousness, and pinpoint pupils.

Naloxone is the reversal agent. For opioid-induced respiratory depression in a PACU setting:

• Dose: Naloxone 0.04–0.1 mg IV, titrated in small increments every 2–3 minutes
• Ceiling: Avoid pushing large boluses – this precipitates acute opioid withdrawal, reverses analgesia, and can cause flash pulmonary edema
• Duration: Naloxone’s half-life (60–90 min) is shorter than most opioids – re-sedation can occur. Continue monitoring for at least 2 hours after administration.

Incentive spirometry

Early use of incentive spirometry promotes alveolar expansion and reduces atelectasis. Coach the patient to take a slow maximal inspiration and hold for 3–5 seconds, aiming for the volume goal set from the patient’s predicted or preoperative baseline. Ten repetitions per hour is the standard recommendation. For full technique and coaching instructions, see the incentive spirometer nursing guide.

Cardiovascular monitoring

Hypotension

Post-anesthesia hypotension is defined as systolic BP less than 90 mmHg or a drop >20% from preoperative baseline. Common causes:

• Hypovolemia – inadequate intraoperative fluid replacement, surgical hemorrhage, third-spacing
• Residual vasodilation – volatile anesthetic agents and propofol are vasodilators that persist beyond extubation
• Cardiac depression – particularly in patients with pre-existing cardiac disease or high-dose volatile agents
• Neuraxial anesthesia – sympathetic blockade causes peripheral vasodilation and can impair cardiac preload

Nursing response:

1. Trendelenburg positioning (unless contraindicated by respiratory compromise or head injury)
2. IV fluid bolus – 250–500 mL isotonic crystalloid over 15–30 minutes, assess response
3. Notify anesthesia/surgical team if unresponsive to fluid challenge
4. Vasopressors (phenylephrine, ephedrine) – require physician order; administered in PACU settings when ordered for refractory hypotension
5. Inspect surgical site and drains – trending drain output and unexpected wound fullness suggest ongoing hemorrhage

If blood loss is suspected as the cause, review the blood transfusion nursing guide for transfusion triggers and administration protocol.

Hypertension

Post-anesthesia hypertension (systolic >180 mmHg or >20% above preoperative baseline) is common. Most cases resolve when the underlying cause is treated:

• Pain – the most frequent cause; adequate analgesia is the first intervention
• Anxiety and emergence agitation – reorientation, reassurance, benzodiazepines if severe
• Hypercarbia – CO2 retention stimulates sympathetic activation; improve ventilation
• Bladder distension – assess for urinary retention and catheterize if indicated
• Pre-existing hypertension – patients who missed morning antihypertensive doses; contact prescriber for oral or IV equivalent

Antihypertensive medication (labetalol, hydralazine, nicardipine) is administered only on physician order when the cause cannot be corrected and the BP poses surgical risk (e.g., intracranial or vascular surgery).

Dysrhythmias

Sinus tachycardia – the most common PACU arrhythmia. Causes: pain, anxiety, hypovolemia, fever, anemia, residual anticholinergic effect. Treat the cause, not the rhythm.

Supraventricular tachycardia (SVT) – rate >150, narrow complex. Initial: vagal maneuvers (Valsalva, carotid sinus massage). If unstable: synchronized cardioversion. If stable: adenosine 6 mg rapid IV push, followed by 12 mg if no response.

Bradycardia – rate <50 with symptoms (hypotension, dizziness). Causes: high spinal block, vagal response, residual opioid effect, beta-blocker continuation. Treatment: atropine 1 mg IV, repeated every 3–5 minutes to a maximum of 3 mg (AHA adult bradycardia algorithm). If unresponsive: transcutaneous pacing.

Premature ventricular contractions (PVCs) – isolated PVCs in a hemodynamically stable patient require no immediate treatment. Frequent PVCs (>6/min), multifocal PVCs, or runs of ventricular tachycardia require immediate cardiac monitoring escalation and physician notification. Causes: electrolyte imbalance (hypokalemia, hypomagnesemia), hypoxia, acid-base disturbance.

PONV: post-operative nausea and vomiting

PONV affects 25–30% of all surgical patients and up to 70–80% of high-risk patients. Patients consistently rate PONV as one of the worst aspects of their surgical experience – worse than pain in many surveys. Complications include wound dehiscence from retching, aspiration, dehydration, delayed discharge, and unplanned hospital admission after ambulatory surgery.

Apfel risk score

The simplified Apfel score predicts PONV risk from four independent risk factors:

Risk interpretation: 0 factors = 10% PONV risk; 1 = 20%; 2 = 40%; 3 = 60%; 4 = 80%.

PONV prophylaxis

The 2020 Fourth Consensus Guidelines (Gan et al) moved the threshold for multimodal prophylaxis down. Earlier guidance reserved combination prophylaxis for patients scoring in the moderate-to-high band; the current recommendation is that any patient with one or more Apfel risk factors receives multimodal pharmacologic prophylaxis, with two agents of different classes as the baseline. Nurses trained on the older risk-stratified algorithm will see more patients arriving with two prophylactic agents already given than that algorithm would predict.

First-line agents:

• Ondansetron 4 mg IV – 5-HT3 antagonist; given at end of surgery
• Dexamethasone 4–8 mg IV – corticosteroid; given at induction; acts synergistically with a 5-HT3 antagonist. Note the dose band widened in the 2020 guidelines from the previous 4–5 mg
• Scopolamine transdermal patch – applied 2–4 hours preoperatively or the evening before; useful for motion-sickness-prone patients

Dexamethasone plus a 5-HT3 antagonist is the recommended first-line adult and pediatric pairing. Patients with three or more risk factors may additionally benefit from TIVA (total intravenous anesthesia with propofol rather than volatile agents) and from avoiding nitrous oxide, both of which lower baseline emetic risk rather than treating it pharmacologically.

PACU treatment of established PONV

1. Ondansetron 4 mg IV – if not given within 6 hours intraoperatively
2. Promethazine 12.5–25 mg IV (slow push over 10–15 min to avoid chemical injury) – dopamine antagonist, useful when 5-HT3 antagonist fails
3. Metoclopramide 10 mg IV – prokinetic; also blocks dopamine in CTZ
4. Positioning – semi-Fowler (30–45°) reduces gastric pressure on the esophagus; lateral position if active vomiting to protect airway
5. Reduce opioids – switch to non-opioid analgesics where possible (ketorolac, IV acetaminophen)
6. Hydration – slow IV fluid infusion; dehydration worsens nausea

Pain management in PACU

Poorly controlled pain in the PACU delays discharge, increases PONV, raises cardiovascular stress, and contributes to chronic post-surgical pain when unaddressed. Multimodal analgesia – combining agents with different mechanisms – provides superior pain control at lower individual opioid doses.

Pain assessment

Assess pain every 15 minutes in Phase I. Use the numeric rating scale (NRS, 0–10) for alert, verbal patients. For non-verbal patients (emergence agitation, cognitive impairment, intubated patients): use the Critical Care Pain Observation Tool (CPOT) or Behavioral Pain Scale (BPS) – behavioral indicators include facial grimacing, vocalization, guarding, and rigidity.

For full pain assessment frameworks, see the pain management nursing guide.

IV opioids

Opioids remain the backbone of PACU analgesia for moderate-to-severe surgical pain. Titrate to effect:

• Morphine – 2–4 mg IV every 5–10 min; peak effect 15–30 min; avoid in renal impairment (active metabolite morphine-6-glucuronide accumulates)
• Hydromorphone – 0.2–0.4 mg IV every 5–10 min; 5x more potent than morphine; preferred when morphine is contraindicated or poorly tolerated
• Fentanyl – 25–50 mcg IV every 5 min; rapid onset (1–2 min), short duration (30–60 min); preferred for procedural and breakthrough pain

Monitor respiratory rate, SpO2, and level of consciousness with every opioid dose. Have naloxone at the bedside.

PCA initiation

When appropriate (alert patient, able to understand the concept), PCA can be initiated in the PACU before floor transfer. The nurse:

1. Programs the pump with physician-ordered parameters (drug, demand dose, lockout, 4-hour limit)
2. Administers a loading dose if ordered
3. Teaches the patient: “Press the button when you feel pain – press it before pain becomes severe”
4. Confirms the patient can physically reach and operate the button
5. Documents pump settings and initial response

For PCA programming, monitoring, and adverse effects, see the epidural and PCA nursing guide.

Non-opioid adjuncts

• Ketorolac 15–30 mg IV – NSAID; effective for musculoskeletal and inflammatory pain; maximum 5-day course; avoid in renal impairment, active GI bleeding, or recent coronary artery bypass
• IV acetaminophen 1 g – safe, effective ceiling analgesic for adults ≥50 kg (1,000 mg every 6 hours or 650 mg every 4 hours, maximum 4 g/day); for adults under 50 kg the label dose is weight-based (15 mg/kg every 6 hours or 12.5 mg/kg every 4 hours, maximum 75 mg/kg/day); use caution in hepatic impairment
• Ketamine – subanesthetic dose (0.1–0.3 mg/kg IV) blocks NMDA receptors; reduces opioid consumption and opioid-induced hyperalgesia; may cause emergence phenomena (dysphoria, hallucinations) – watch for and have benzodiazepine available

Regional anesthesia analgesia in PACU

Patients who received spinal, epidural, or peripheral nerve blocks arrive in PACU with a variable degree of residual block. Key nursing assessments:

Epidural analgesia:

• Assess dermatomal level every 30 minutes using ice or alcohol swab
• Monitor motor block – the patient should be unable to ambulate until motor function returns
• Monitor for hypotension from sympathetic blockade – keep IV access patent and bolus fluid as ordered
• Check infusion rate, concentration, and catheter securement – assess insertion site for leakage or swelling

Peripheral nerve blocks:

• Assess sensory and motor function in the blocked extremity
• Warn the patient that the block will wear off in 8–24 hours depending on the agent used (bupivacaine lasts longer than ropivacaine, liposomal bupivacaine up to 72 hours)
• Ensure adequate oral or IV analgesia is ordered and given before block resolution – the transition is abrupt

For epidural-specific monitoring protocols, see the epidural and PCA nursing guide.

Thermoregulation

Perioperative hypothermia

Core temperature below 36°C at PACU admission is common. Causes:

• Cold operating room environment (typically 18–21°C)
• Vasodilation from anesthetic agents exposing the body’s warm core to the cold periphery
• Anesthetic suppression of the hypothalamic thermoregulatory center
• Prolonged exposure of body cavities during surgery
• Large volumes of unwarmed IV fluids or irrigants

Hypothermia causes vasoconstriction, shivering, coagulopathy, delayed drug metabolism, and poor wound healing.

Shivering

Post-anesthesia shivering occurs in 40–60% of patients recovering from general anesthesia. It raises oxygen consumption, which matters for patients with limited cardiopulmonary reserve. The often-quoted 300–400% increase came from small studies of younger volunteers; in 111 elderly postoperative patients, mean oxygen consumption was 38% higher in those who shivered (Frank 1995). Shivering is also intensely distressing for patients.

Management:

1. Forced-air warming blanket (Bair Hugger) – most effective intervention; direct warm air circulation raises core temperature rapidly
2. Warmed IV fluids – prevent further cooling from infusion of room-temperature crystalloids
3. Extra blankets – less effective for core temperature but important for patient comfort
4. Meperidine 12.5–25 mg IV – the only opioid with specific anti-shivering effect via kappa-opioid receptors; dramatically reduces shivering within minutes (use with caution due to seizure risk with monoamine oxidase inhibitors)

Malignant hyperthermia

Malignant hyperthermia (MH) is a rare, potentially fatal pharmacogenetic disorder triggered by volatile anesthetic agents (halothane, sevoflurane, desflurane, isoflurane) and succinylcholine. The underlying defect is in the ryanodine receptor (RYR1) gene, causing uncontrolled calcium release from skeletal muscle sarcoplasmic reticulum.

Clinical presentation (PACU nurses must recognize this):

• Unexpected tachycardia – often the earliest sign
• Masseter muscle rigidity (jaw stiffness) after succinylcholine
• Rising end-tidal CO2 (if still intubated) or increasing respiratory rate
• Hyperthermia – can exceed 40°C rapidly (late sign)
• Muscle rigidity, dark cola-colored urine (myoglobinuria)
• Metabolic and respiratory acidosis

Emergency nursing response:

1. Call for help and notify anesthesia immediately
2. Stop the triggering agent (if still in OR – PACU nurses receiving a hot patient should alert anesthesia)
3. Dantrolene 2.5 mg/kg IV – the definitive treatment; inhibits calcium release from sarcoplasmic reticulum; repeat as often as needed until signs resolve (falling ETCO2, slowing heart rate); MHAUS notes that doses above 10 mg/kg may be required
4. Active cooling: ice packs to axillae, groin, and neck; cold IV saline; cool body cavities if open; per MHAUS, cool if core temperature is above 39°C and stop at below 38°C
5. Sodium bicarbonate for metabolic acidosis
6. Treat hyperkalemia (calcium chloride, insulin/dextrose)
7. Maintain urine output >1 mL/kg/hr with aggressive fluids to protect kidneys from myoglobin

Mortality from an acute MH crisis exceeded 70% before dantrolene became available in the late 1970s. In the dantrolene era it is usually reported below 5%, though registry data put it higher when treatment is delayed: a Japanese national analysis found 9.6% mortality among patients who received dantrolene against 30.8% among those who did not, with the interval from first sign to dantrolene averaging 100 minutes in the patients who died versus 45 minutes in survivors. Time to the first dose is what changes the outcome, which is why MHAUS specifies that dantrolene be accessible within 10 minutes of the decision to treat. Every institution must have a MH cart with dantrolene stocked. The Malignant Hyperthermia Association of the United States (MHAUS) hotline (1-800-MH-HYPER) is available 24/7 for crisis support.

Regional anesthesia recovery

Patients who have received neuraxial anesthesia (spinal or epidural) have specific recovery requirements that differ from patients recovering from general anesthesia.

Spinal anesthesia

After spinal anesthesia, the block regresses from caudal to cephalad as local anesthetic is absorbed from the intrathecal space. The sequence of return is predictable:

• Sensation returns before motor function – the patient may feel touch before being able to move
• Proprioception (position sense) returns last – the patient may be able to move but cannot accurately sense limb position, making them fall risk even after motor return
• Autonomic function (vasoconstriction, bladder control) may lag behind sensory and motor return

Nursing assessments for spinal block:

• Test sensory level with ice or alcohol swab – identify the highest dermatomal level with loss of cold sensation
• Monitor BP every 5–15 minutes – sympathetic block causing hypotension persists until the block regresses below T10
• Assess motor strength – straight leg raise, dorsiflexion, plantar flexion
• Assess bladder – urinary retention is common; catheterize if patient cannot void within 6–8 hours and bladder is distended
• Document regression q30 minutes until bilateral sensorimotor function has returned

Criteria for ambulation after spinal: bilateral return of sensation to perineum (S4-5) and motor function sufficient for weight bearing, with proprioception sufficient for balance.

Epidural block assessment

The principles are the same as spinal, but the block is maintained by continuous infusion or patient-controlled epidural analgesia (PCEA). The dermatomal level can be adjusted by changing infusion rate.

Epidural catheter removal criteria:

• Epidural space coagulation should be confirmed adequate before removal (per anesthesia order)
• Anticoagulation is the primary concern – removal should not occur within time windows specified by ASRA guidelines (e.g., not within 12 hours of last prophylactic LMWH dose, not within 24 hours of therapeutic LMWH)
• After removal, inspect catheter tip – confirm catheter is intact (the tip should have a colored marking at the terminal end)
• Maintain patient supine for 30–60 minutes after removal

Discharge criteria

Phase I to Phase II (or floor)

ASPAN standards and the Modified Aldrete Score guide Phase I discharge. The patient must meet all:

Phase II to home (ambulatory surgery)

PADSS score ≥9 is the objective measure, but additional criteria must be met before safe home discharge:

• Tolerating oral fluids (sips of clear liquid without vomiting x30 min)
• Has voided (or has received a urology consult if cannot void and bladder is not distended – some protocols allow home without voiding if patient is low-risk)
• Ambulating safely – gait is steady without assistance
• Responsible adult escort is present to receive verbal and written discharge instructions
• Written discharge instructions signed and given – include wound care, medication schedule, dietary restrictions, activity restrictions, follow-up appointment, and when to go to the ER

Handoff to floor or ICU

When a PACU patient is ready for transfer to an inpatient unit, the receiving nurse must be given a complete, structured handoff. Joint Commission standard PC.02.02.01 requires an interactive, bidirectional handoff – the receiving nurse must have opportunity to ask questions and confirm critical information.

A complete PACU-to-floor SBAR handoff includes:

• Situation: Patient name, MRN, procedure, current acuity, reason for admission level (ICU vs. floor)
• Background: Surgical and medical history, allergies, pre-anesthetic baseline vitals and mental status, type of anesthesia
• Assessment: Intraoperative events (blood loss, fluid balance, medication given, complications); current Aldrete score; unresolved issues (pain level, nausea, bleeding concerns)
• Recommendation: IV access status, current infusions, catheter/drain status, post-op orders confirmed, pending labs, first scheduled medication, follow-up needed within first hour

What must always be communicated:

• Airway events (laryngospasm, difficult intubation, re-intubation)
• Estimated blood loss and replacement – cumulative IV fluids, blood products given
• All medications given in PACU (opioids, antiemetics, reversal agents, antibiotics)
• Any new clinical concerns that emerged in PACU (unexpected hypotension, arrhythmia, confusion)
• Unresolved pain or nausea – what has been tried and the response
• Regional anesthesia details – block placed, local anesthetic used, expected duration, catheter location if in situ

Special populations

Pediatric patients

Children recovering from anesthesia have unique challenges:

• Parental presence – ASPAN supports parental presence in the PACU when the child is alert enough to benefit. Parental presence reduces emergence agitation and anxiety in children aged 2–7.
• Emergence delirium – occurs in 10–80% of children after volatile anesthesia (especially sevoflurane). The child is agitated, inconsolable, thrashing, does not appear to recognize caregivers, and may injure themselves. Distinguished from pain by: emergence delirium is self-limiting (peaks at 5–15 min post-extubation), whereas pain is persistent and responsive to analgesia. The Pediatric Anesthesia Emergence Delirium (PAED) scale scores five behaviors 0–4.
• Non-opioid preference – IV acetaminophen, ketorolac, dexmedetomidine, and regional anesthesia reduce opioid requirements and emergence delirium risk in children.
• Vital signs – pediatric normal ranges differ significantly from adults. Reference age-specific norms using the vital signs by age guide.

Elderly patients

• Cognitive baseline – establish preoperative cognitive status (confusion? dementia?) from chart review and family history. Post-operative delirium in the elderly has an incidence of 10–60% after major surgery – it is not the same as emergence delirium.
• Fall risk – elderly patients are at high fall risk due to residual block, orthostatic hypotension, confusion, and unfamiliar environment. Bed alarm on at all times, siderails up, call bell within reach.
• Delirium prevention – reorient frequently, keep environment calm and well-lit, avoid anticholinergic medications (diphenhydramine, promethazine), ensure glasses and hearing aids are returned as soon as safe.
• Polypharmacy – check for interactions between home medications and PACU medications; elderly patients metabolize drugs more slowly.

Patients with obesity

• Positioning – reverse Trendelenburg or semi-Fowler (30–45°) improves respiratory mechanics by reducing abdominal pressure on the diaphragm. Never place obese patients supine flat without specific indication.
• OSA considerations – patients with obstructive sleep apnea who use CPAP at home should have their device available in PACU. CPAP is reinstituted as soon as the patient can tolerate it – typically when they are arousable and can follow commands.
• Extended monitoring – patients with severe obesity and OSA are at higher risk for OIRD and oxygen desaturation during sleep. Consider extended Phase I monitoring (60–90 min rather than 30 min) before floor transfer.
• IV access – large veins are often deeply buried; confirm patency and consider ultrasound-guided access if the site is in doubt.

NCLEX high-yield: 20 must-know points

PACU complications quick-reference

Clinical sources

This article draws on the following authoritative references:

• ASPAN 2025–2026 Perianesthesia Nursing Standards, Practice Recommendations and Interpretive Statements – American Society of PeriAnesthesia Nurses
• ASA Standards for Post-Anesthesia Care – American Society of Anesthesiologists (last amended October 2024)
• Aldrete JA. The post-anesthesia recovery score revisited. Journal of Clinical Anesthesia. 1995;7(1):89–91.
• Apfel CC, Läärä E, Koivuranta M, et al. A simplified risk score for predicting postoperative nausea and vomiting. Anesthesiology. 1999;91:693–700.
• Chung F, Chan VW, Ong D. A post-anesthetic discharge scoring system for home readiness after ambulatory surgery. Journal of Clinical Anesthesia. 1995;7(6):500–506. (PADSS)
• Gan TJ, Belani KG, Bergese S, et al. Fourth Consensus Guidelines for the Management of Postoperative Nausea and Vomiting. Anesthesia & Analgesia. 2020;131(2):411–448.
• Malignant Hyperthermia Association of the United States (MHAUS). Clinical resources and emergency protocols. mhaus.org
• The Joint Commission. Provision of Care, Treatment, and Services standard PC.02.02.01, EP 2 (hand-off communication; formerly NPSG 02.05.01, converted to a standard in 2010)
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