Voiding and drinking are habits, not discharge criteria

Why it matters

Every PACU has discharge rituals, and the two most durable are the drink and the void. The 2013 ASA practice guideline for postanesthetic care, Section V, Protocol for Discharge, states that the literature is insufficient to evaluate the benefits of requiring patients to urinate before discharge asa-pacu-2013. What sits beside that statement is not an evidence grade but an opinion survey, and the survey went the other way from the convention: 85% of surveyed members supported not requiring voiding before discharge, and requiring patients to drink water before discharge appears among the interventions members did not support asa-pacu-2013.

The consequence of getting this wrong is a patient held in the PACU, or a bed held from the next patient, for a criterion nobody can source.

Mechanism

The rituals have a physiological rationale, which is why they persist. Neuraxial anesthesia and opioids impair detrusor function and the sensation of bladder fullness, so retention after discharge is a real risk, and a void before leaving was the proxy for a working bladder. Nausea after anesthesia is real, and tolerating fluid was the proxy for a settled gut. The mechanism explains the habit; it does not establish that applying the proxy to every patient changes anything, and the guideline finds that the literature cannot say it does.

Evidence

The guideline’s evidentiary statement is the sentence the day is built on: the literature is insufficient to evaluate the benefits of requiring that patients urinate before discharge asa-pacu-2013. The member survey reported alongside it records support for not requiring voiding before discharge at 85%, for requiring a responsible individual to accompany the patient home at 95%, and for not requiring a mandatory minimum stay in recovery at 85% asa-pacu-2013. Requiring that patients drink water before discharge is listed among the interventions members did not support asa-pacu-2013.

On urine output more generally, the guideline states that the original literature indicated that assessment of urine output is effective in identifying patients with urinary retention, Category B3-B evidence, that new literature is insufficient to further evaluate that finding, and that assessment of urine output and voiding should be done on a case-by-case basis for selected patients or selected procedures asa-pacu-2013.

So the teaching structure is: the guideline declines to endorse the convention, a majority of surveyed members actively favor dropping it, and case-by-case assessment for selected patients is what replaces it asa-pacu-2013.

What this does not show

This day has one ledger row. That is sufficient, because the source is the entire argument, but it means the day cannot say anything the guideline does not. The guideline is thirteen years old and no successor practice guideline has been found; confirm that before asserting it is current asa-pacu-2013.

The guideline is also not the whole picture. The ASA Standards for Postanesthesia Care, last amended 23 October 2024, state in Standard V, verbatim: a physician is responsible for the discharge of the patient from the postanesthesia care unit; when discharge criteria are used, they must be approved by the Department of Anesthesiology and the medical staff, and they may vary depending upon whether the patient is discharged to a hospital room, to the ICU, to a short stay unit or home; in the absence of the physician responsible for the discharge, the PACU nurse shall determine that the patient meets the discharge criteria, and the name of the physician accepting responsibility for discharge shall be noted on the record asa-pacu-standards-2024. The obligation is current and the content of the criteria is left to the institution. A search for a newer practice guideline found only the 2013 update and the 2002 original; the 2024 change is to the Standards, not the guideline asa-pacu-2013.

One of the three discharge instruments now has its items, and the other two have been established as unreachable rather than merely unread. The fast-track criteria were read on 2026-09-08 from the source paper’s own scoring table, which the publisher renders as an image with no alternative text, so they were transcribed by eye. There are seven categories, each scored 0, 1 or 2 for a maximum of 14: level of consciousness, physical activity, hemodynamic stability, respiratory stability, oxygen saturation status, postoperative pain assessment, and postoperative emetic symptoms white-1999. The threshold is quoted in that paper’s own appendix caption: a minimal score of 12, with no score below 1 in any individual category, would be required for a patient to be fast-tracked, that is to bypass the recovery unit, after general anesthesia white-1999.

Hold that instrument as loosely as its authors do. It is a brief communication reporting a retrospective analysis of recovery data from 216 consenting female outpatients having laparoscopic tubal ligation or cholecystectomy at a single center, all of whom received analgesic and antiemetic prophylaxis, and the authors state that additional prospective clinical studies are required to validate the utility of this new scoring system white-1999. It is a proposal compared against an existing score, not a validated one.

The other two item lists are not available and this project now says so rather than leaving a marker. The post-anesthetic discharge scoring system’s threshold of at least 9 is confirmed, along with its design as a randomized open study in 247 ambulatory patients, a correlation of 0.89 with clinical fitness for discharge, and an internal consistency of 0.65 against 0.14 for clinical criteria; its five items are not in the abstract and the institution does not hold the full text chung-1995-padss. The modified Aldrete paper is classified by its publisher as correspondence, carries no abstract at all, and is likewise not held aldrete-1995. Three retrieval rounds have failed on both by every available route, and no browser session will change that. What the fast-track paper does supply, second hand, is that its own score takes into consideration pain and emetic symptoms as well as the Aldrete assessments of consciousness, physical activity, and hemodynamic and respiratory stability, which is one author characterizing another’s instrument rather than the instrument itself white-1999.

The neuraxial comparison has its trial: low-risk ambulatory patients after short-acting spinal or epidural anesthesia were discharged without voiding when a bladder ultrasound was below 400 mL, 22 min sooner than the standard pathway, P=0.002, with no urinary problems or returns mulroy-2002. Retention risk after a peripheral nerve block in ambulatory patients has been searched for across two retrieval rounds and not found, so this page gives no figure for it.

At the bedside

Know which of your PACU’s discharge criteria are sourced and which are habit. The escort is sourced by survey at 95%; the drink and the void are not asa-pacu-2013. Local practice differs. whether voiding is required before discharge, and for whom, differs between institutions and after neuraxial anesthesia in particular; follow local protocol and be able to say what it rests on.

Assess the bladder case by case, in the patients and after the procedures where retention is likely, because that is what the guideline replaces the blanket rule with asa-pacu-2013.

Write the discharge against the criteria your institution has approved, and know who is accountable for the decision, because the obligation is current even where its content is not specified.

Check yourself

Three items. Every option carries an explanation. Progress is not saved.