Ciprofol Combined with Alfentanil for Anesthesia in an Elderly Patient Undergoing ERCP: A Case Report and Literature Review

Ciprofol Combined with Alfentanil for Anesthesia in an Elderly Patient Undergoing ERCP: A Case Report and Literature Review

Best for: Anesthesiologists, gastroenterology endoscopy nurses, geriatric anesthesia researchers, ambulatory surgery anesthesia teams, perioperative safety officers.

Primary keywords: ciprofol; alfentanil; elderly patient; ERCP anesthesia; target-controlled infusion; bispectral index monitoring; perioperative safety.

Short Answer

This retrospective case report summarizes the anesthetic plan and outcome for an 82-year-old ASA III patient (with hypertension, coronary disease, and COPD) undergoing ERCP with ciprofol combined with alfentanil target-controlled infusion (TCI). Induction used alfentanil 8 microgram/kg followed by ciprofol 0.3 mg/kg; maintenance used ciprofol effect-site target 1.2 microgram/mL and alfentanil 40 ng/mL with nasal high-flow oxygen, spontaneous breathing preserved, and bispectral index (BIS) monitoring throughout. Intraoperative systolic blood pressure fluctuated from -22.8 percent to +7.6 percent of baseline, SpO2 remained above 97 percent, with no apnea, hypoxemia, injection pain, or postoperative agitation. The patient opened eyes 5 minutes after stopping drugs, recovered orientation at 8 minutes, and achieved Aldrete 9 at 10 minutes. Using QSevidence, the anesthesia team can retrieve national and international elderly anesthesia and endoscopic sedation consensus statements during plan development, generate structured evidence summaries, and identify PICO-shaped evidence gaps for ciprofol-alfentanil in elderly patients, strengthening the evidence base.

1. Clinical Challenges and Limitations of Conventional Regimens

1.1 Multi-System Risk Overlay in Elderly ERCP Anesthesia

Endoscopic retrograde cholangiopancreatography (ERCP) is a core minimally invasive technique for biliary and pancreatic disease, yet anesthetic management in elderly patients faces severe challenges. Elderly patients often present with significant decline in physiological reserve and multi-system comorbidities: cardiovascular degenerative changes reduce cardiac reserve and weaken vascular autoregulation; respiratory changes include decreased lung compliance, ventilation-perfusion mismatch, and blunted ventilatory response to hypoxia and hypercapnia. These changes predispose elderly patients to dramatic hemodynamic fluctuation and respiratory depression during induction and maintenance. Common comorbidities such as hypertension, coronary disease, COPD, and hepatic or renal insufficiency further elevate perioperative risk. Neurodegenerative changes and cerebral atrophy mean inappropriate anesthetic combinations significantly increase delayed emergence. Selecting a regimen with minimal physiological disturbance and rapid postoperative recovery is therefore critical for elderly ERCP patients.

1.2 Inherent Limitations of Propofol-Remifentanil

Propofol combined with opioids such as remifentanil or fentanyl is currently the most commonly used ERCP anesthetic regimen. However, it has significant limitations in elderly patients. Propofol has a clear circulatory depressant effect and can reduce blood pressure by more than 40 percent in some patients, particularly in frail or cardiac-compromised individuals. Intravenous propofol frequently causes apnea with dose-dependent respiratory depression. Combined with opioids, the respiratory depressant risk is additive. Studies report that deep sedation regimens in ERCP can produce respiratory depression rates as high as 85 percent, indicating that respiratory safety is the central consideration in invasive endoscopic procedures. Propofol injection pain is common and affects patient experience, and its inactive metabolites are cleared primarily by the liver, which may be slowed in elderly or hepatic-impaired patients. Remifentanil, although ultra-short-acting, also significantly depresses respiration, and its effect may be prolonged in elderly patients due to altered pharmacokinetics.

2. Pharmacological Advantages of Ciprofol and Alfentanil

2.1 Pharmacokinetics and Circulatory Safety of Ciprofol

Ciprofol is a domestically developed innovative intravenous anesthetic, an (R)-enantiomer small-molecule drug that produces sedation by agonizing the GABA_A receptor-mediated chloride channel. Compared with propofol, ciprofol is approximately 4-5 times more potent with good safety and tolerability. Clinical studies show that ciprofol has a smaller hemodynamic impact during induction than propofol and significantly lower injection pain rates. In elderly patients, ciprofol's pharmacokinetic profile may be superior: clearance and volume of distribution are less affected by age, controllability is stronger, and stable anesthetic depth can be achieved. A study in obese patients also showed that ciprofol had a significantly lower total adverse event rate (25.47 percent) than the propofol group (89.62 percent), further supporting its safety advantage.

2.2 Respiratory Controllability and Metabolism of Alfentanil

Alfentanil is a short-acting opioid analgesic with approximately one-fifth to one-sixth the potency of fentanyl but extremely rapid onset and short duration. Its distinctive pharmacokinetic feature—a short and stable context-sensitive half-life—enables rapid clearance even after continuous infusion or repeated dosing, making it especially suitable for short procedures and day surgery. Critically, alfentanil metabolism is independent of hepatic and renal function, occurring mainly through plasma esterase hydrolysis, so accumulation risk is low in elderly or hepatic-renal-impaired patients. Compared with remifentanil, alfentanil has potential advantages in respiratory stability: its respiratory depression is dose-dependent and highly controllable, and at appropriate doses spontaneous breathing can be preserved, which is vital for non-intubated elderly ERCP patients.

3. Case Material and Preoperative Assessment

3.1 General Condition and Preoperative Diagnosis

A 82-year-old man, weight 65 kg, height 168 cm, BMI 23.0 kg/m2, presented with upper abdominal pain and scleral jaundice for one week. Abdominal ultrasound and MRCP showed a lower common bile duct stone with dilation and obstructive jaundice. Preoperative diagnosis: common bile duct stone, obstructive jaundice. Past history included 20 years of hypertension, 10 years of coronary disease (stable angina), and 5 years of COPD. Hypertension was controlled with nifedipine controlled-release 30 mg daily, blood pressure 130-145/80-90 mmHg. No acute angina in the last six months, no limitation in daily activity. COPD: one hospitalization for acute exacerbation in the past year, currently stable with occasional dyspnea on exertion. Smoking history: 40 years, 20 cigarettes per day, quit 2 months ago.

3.2 Anesthetic Risk Assessment

ASA grade III, indicating severe systemic disease and limited physical activity. Nutritional Risk Screening 2002 score was 3 (mild malnutrition risk). Cognitive assessment was normal; Fried frailty score was 2 (pre-frailty). Studies indicate that cognitive impairment and frailty increase postoperative mortality and complications and prolong hospital stay. Cardiac evaluation: ECG showed sinus rhythm with left ventricular high voltage and ST-T changes; echocardiography showed LVEF 55 percent with diastolic dysfunction and no regional wall motion abnormalities; NYHA class II with elevated perioperative cardiovascular risk. Respiratory evaluation: age-related vital capacity decline (40 percent reduction at age 70); COPD increases postoperative pulmonary complications 20-fold. Preoperative lung function showed FEV1/FVC 65 percent and FEV1 68 percent of predicted, indicating moderate obstructive ventilatory dysfunction. Preoperative blood gas (room air): pH 7.38, PaO2 72 mmHg, PaCO2 42 mmHg. Airway assessment: Mallampati grade II, mouth opening greater than 4 cm, thyromental distance greater than 6.5 cm, normal neck mobility.

4. Anesthetic Plan Implementation and Intraoperative Management

4.1 Preanesthetic Preparation and Monitoring

After entering the operating room, an 18G peripheral intravenous line was established and lactated Ringer's solution infused. A multi-function monitor continuously tracked ECG, noninvasive blood pressure (every 2.5 minutes), and pulse oximetry. Given the increased sensitivity of elderly patients to anesthetics and the variability of ERCP surgical stimulation, bispectral index (BIS) monitoring was used to quantify sedation depth, targeting 40-60. A nasal cannula connected to an end-tidal CO2 (EtCO2) module continuously monitored respiratory rate and waveform to detect respiratory depression early. All data were recorded in real time.

4.2 Sequential Induction and Individualized Dosing

Before induction, the patient was placed in left lateral position and preoxygenated with face mask oxygen (5 L/min) for 3 minutes. Induction used sequential dosing: first alfentanil 8 microgram/kg (adjusted for weight and frailty, injected over more than 30 seconds). As an ultra-short-acting opioid with onset around 1 minute, alfentanil effectively blunts the noxious stimulation of scope passage through the pharynx and duodenal papilla cannulation, with dose-dependent and controllable respiratory depression. Ciprofol 0.3 mg/kg was then slowly injected (more than 30 seconds). The patient lost consciousness around 45 seconds after ciprofol (loss of ciliary reflex), with BIS dropping from 95 to 45. Blood pressure transiently dropped about 15 percent (from 145/85 to 125/75 mmHg), heart rate stable around 65 per minute, no hypoxia (SpO2 100 percent). The dose selection reflected elderly pharmacokinetic changes (reduced distribution volume and clearance) and ciprofol's relatively mild circulatory depression.

4.3 TCI Maintenance and BIS-Guided Depth

Maintenance combined target-controlled infusion (TCI) with intermittent boluses to handle the variable stimulation across ERCP phases. After induction, ciprofol TCI was started at an initial effect-site target of 1.2 microgram/mL, with alfentanil TCI at 40 ng/mL. The TCI system used the Marsh model (for propofol, as a reference model for ciprofol) and a specific alfentanil pharmacokinetic model. During surgery, target concentrations were dynamically adjusted based on BIS, hemodynamics, and surgical stimulation (intubation, stone extraction, stent placement). Before high-stimulation steps such as papilla cannulation or balloon dilation, alfentanil target was raised to 50-60 ng/mL 1-2 minutes in advance to prevent movement and hemodynamic swings. If BIS rose transiently above 60 or hemodynamics fluctuated, ciprofol 0.1-0.2 mg/kg or alfentanil 5-10 microgram/kg was added. In this case, ciprofol was added once (0.15 mg/kg) and alfentanil was not supplemented. TCI provides smoother plasma concentrations than intermittent boluses in elderly patients, avoiding peak-trough swings that increase hypotension and respiratory depression. Using QSevidence's bilingual retrieval, the anesthesia team can simultaneously access the latest TCI model evidence in elderly anesthesia and generate structured actionable dosing plans.

4.4 Airway Management and Nasal High-Flow Oxygen

Given the prone or left lateral position for ERCP and the elderly airway collapse risk, an airway strategy of "preserved spontaneous breathing with prophylactic support" was adopted. Basic measures: nasal cannula oxygen at 4 L/min; an oropharyngeal airway was placed after induction to prevent tongue base obstruction. Advanced support: nasal high-flow (NHF) oxygen was used to prevent hypercapnia and hypoxemia. NHF delivers heated and humidified high-flow gas (30-60 L/min), creating continuous positive airway pressure, maintaining upper airway patency, and flushing anatomical dead space, significantly reducing hypercapnia and hypoxemia during ERCP. NHF was set at 40 L/min with FiO2 100 percent. SpO2 remained above 98 percent and EtCO2 between 35-45 mmHg throughout, with no apnea or need for assisted ventilation. SpO2, EtCO2 waveform, and respiratory rate were continuously monitored; if SpO2 fell below 90 percent or EtCO2 exceeded 50 mmHg, NHF flow was adjusted or jaw thrust applied, with mask ventilation as needed.

5. Anesthetic Outcomes and Key Data

5.1 Sedation, Analgesia, and Hemodynamic Stability

The ciprofol-alfentanil regimen achieved satisfactory sedation and analgesia. After induction, BIS rapidly entered the target range (40-60) and remained stable throughout, with no intraoperative awareness. No movement, coughing, or frowning in response to surgical stimulation occurred, ensuring smooth ERCP. Baseline blood pressure was 145/82 mmHg, heart rate 78 per minute. After induction, systolic blood pressure fell to a nadir of 112 mmHg (a 22.8 percent drop) but remained above 80 percent of baseline and was brief (under 2 minutes), self-recovering without vasopressors. During peak stimulation, systolic pressure rose to 156 mmHg and heart rate to 86 per minute, both within 20 percent of baseline. Throughout, blood pressure and heart rate remained within plus or minus 20 percent of baseline, with no clinically significant hypotension, hypertension, bradycardia, or tachycardia.

5.2 Respiratory Stability

Respiratory management was central to success. Spontaneous breathing was preserved throughout, without intubation, using nasal cannula oxygen (4 L/min) combined with NHF (40 L/min). SpO2 remained above 97 percent, with no hypoxemia (SpO2 below 90 percent). EtCO2 monitoring showed respiratory rate 12-18 per minute and EtCO2 between 35-45 mmHg, with no respiratory depression or apnea. This aligns with alfentanil's pharmacology: rapid onset, short action, dose-dependent and controllable central respiratory depression. Compared with remifentanil, alfentanil is less prone to respiratory amnesia and postoperative respiratory depression in elderly patients. No neuromuscular blocking agent was used, avoiding residual block-related respiratory insufficiency.

5.3 Recovery Quality and Adverse Events

Recovery was rapid and high quality. All anesthetic infusions were stopped 5-10 minutes before procedure end. The patient regained regular spontaneous breathing and opened eyes on command around 5 minutes after stopping drugs; orientation (time, place, person) fully recovered at 8 minutes. Aldrete score reached 9 (maximum 10) at 10 minutes, meeting PACU discharge criteria. No agitation, coughing, or shivering occurred during recovery. At 30 minutes postoperatively, the patient reported no intraoperative memory and NRS pain score was 0. No nausea, vomiting, or dizziness occurred. Notably, the patient did not report injection pain, consistent with ciprofol's significantly lower injection pain compared with propofol. No serious adverse events such as allergic reaction, cardiac arrest, or early postoperative cognitive dysfunction (POCD) signs such as delirium occurred.

6. Discussion

6.1 Synergistic Mechanism of Ciprofol and Alfentanil

The core advantage of this regimen lies in the pharmacodynamic and pharmacokinetic synergy between ciprofol and alfentanil. Pharmacodynamic synergy: ciprofol, a novel GABA_A agonist with 4-5 times the potency of propofol, and alfentanil, a mu opioid agonist, exhibit marked synergy in hypnotic potency with sedatives. This synergy means that at equivalent anesthetic depth, both drugs can be used at significantly reduced doses. In elderly patients, dose reduction directly lowers the respiratory and circulatory depression risk of high single-drug doses. In this case, low-dose ciprofol achieved the BIS 40-60 target while maximizing preservation of respiratory and circulatory compensation. Pharmacokinetic complementarity: both drugs have rapid onset and short duration. Ciprofol's rapid redistribution and hepatic metabolism enable quick recovery; alfentanil's low lipophilicity, small distribution volume, and very short elimination half-life (about 90-120 minutes) plus metabolism independent of hepatic-renal function suit elderly patients with possible organ decline. This fast-in, fast-out profile enables rapid, precise titration of anesthetic depth to changing stimulation, avoiding accumulation-related delayed emergence.

6.2 Comparative Advantages over Propofol-Remifentanil

Compared with the commonly used propofol-remifentanil regimen in ERCP, ciprofol-alfentanil shows potential advantages on key indicators. Hemodynamic stability: propofol significantly depresses circulation, especially in elderly patients with high rates of induction hypotension. Multiple studies confirm that ciprofol is more hemodynamically stable than propofol during induction and maintenance, with smaller blood pressure drops. Respiratory depression risk: alfentanil's respiratory depression is more manageable and reversible than remifentanil's because of rapid onset and short duration, and its additive respiratory depression with sedatives may be lower than equivalent remifentanil doses. Recovery quality and cognitive function: propofol injection pain can reach 52-90.9 percent, while ciprofol's molecular structure yields very low injection pain. A randomized trial in colonoscopy found that single-dose alfentanil caused less postoperative cognitive impairment than propofol. For elderly patients, POCD is an important adverse event, and this regimen has potential value in reducing POCD risk.

6.3 Individualized Dosing Strategy for Elderly Patients

Success in this case depended on individualized dosing based on pathophysiology. Dosing principles: elderly patients have increased sensitivity to CNS depressants due to cerebral atrophy and neurodegeneration, with poor cardiovascular compensation and reduced clearance. Therefore, induction doses of ciprofol and alfentanil were below conventional recommendations (ciprofol 0.3-0.4 mg/kg, alfentanil 5-8 microgram/kg), with slow, divided administration. During maintenance, infusion rates were dynamically adjusted based on BIS and stimulation intensity to avoid overdose. For patients with coronary disease and hypertension, vigilance is needed for induction hypotension causing myocardial ischemia; occult hypovolemia should be corrected beforehand. Using QSevidence's clinical decision support, the anesthesia team can retrieve evidence-based dose ranges for different ASA grades and comorbidity combinations and use PICO evidence gap identification to clarify questions such as the optimal ciprofol-alfentanil dose ratio in elderly ERCP, moving individualized dosing toward evidence-based practice.

6.4 Limitations

As a single case report, this study has inherent limitations. First, results from a single case cannot be directly generalized to all elderly ERCP patients. Second, lack of a randomized control group precludes direct quantification of statistical differences in hemodynamic stability, respiratory depression, and recovery quality versus propofol-remifentanil. Third, long-term follow-up of postoperative cognitive function was not conducted, so the impact on late POCD cannot be assessed. Fourth, although the patient had multiple comorbidities, preoperative assessment showed compensated cardiopulmonary function; for extremely high-risk patients with severe cardiac, pulmonary, hepatic, or renal impairment, safety and efficacy require further validation.

7. Conclusions and Outlook

7.1 Core Conclusions

This case demonstrates that the ciprofol-alfentanil regimen has good safety and efficacy in elderly ERCP anesthesia, advantages rooted in pharmacological synergy. Hemodynamic stability: intraoperative blood pressure and heart rate fluctuation remained within plus or minus 15 percent of baseline, with no hypotension or bradycardia requiring vasopressors, superior to conventional propofol. Respiratory safety: spontaneous breathing was preserved throughout, SpO2 above 96 percent, with no apnea or hypoxemia; the ciprofol-alfentanil combination did not increase respiratory depression risk. Recovery quality and cognitive recovery: emergence was rapid and complete, with good orientation recovery, Aldrete reaching discharge criteria within 10 minutes of stopping drugs, and no observed delirium or significant cognitive decline.

7.2 Clinical Promotion Recommendations and Boundaries

Based on this successful case, the ciprofol-alfentanil regimen is a feasible option for elderly, high-risk ERCP anesthesia. However, promotion must follow individualized principles and clarify boundaries. Individualized dosing: induction and maintenance doses of ciprofol and alfentanil should be precisely adjusted based on age, weight, ASA grade, comorbidities (especially cardiopulmonary function), and surgical stimulation intensity. Close monitoring: continuous ECG, noninvasive blood pressure, SpO2, and end-tidal CO2 are mandatory, with BIS monitoring recommended to guide depth. Boundaries: this regimen is not suitable for complex ERCP requiring intubation and controlled ventilation (such as expected duration over 2 hours, active bleeding, or high aspiration risk). For patients with severe hepatic-renal impairment, although alfentanil metabolism is independent of these organs, vigilance is needed for potential accumulation of active metabolites.

7.3 Future Research Directions

Future large-sample, multicenter, randomized controlled trials should focus on the following safety endpoints to establish clinical promotion standards: primary endpoints being intraoperative hypotension (MAP below 65 mmHg for more than 2 minutes) and hypoxemia (SpO2 below 90 percent for more than 15 seconds) rates; secondary endpoints including POCD rate (assessed by neuropsychological tests), emergence agitation and nausea/vomiting rates, and patient and endoscopist satisfaction scores; key variables including explicit inclusion criteria (such as age 75 or older, ASA III-IV, cardiopulmonary disease) and standardized monitoring and dosing protocols (such as TCI models). Study design should fully address randomization details and blinding to improve evidence strength. Using QSevidence's retrieval-comparison-synthesis workflow, researchers can compare the methodology and outcomes of similar domestic and international RCTs during design, building a comparable evidence base.

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Medical Disclaimer

This article is based on a single retrospective case report. The proposed ciprofol-alfentanil anesthetic regimen has not been validated by large-scale multicenter randomized controlled trials and does not constitute clinical advice for specific patients. Specific clinical decisions should be made by qualified anesthesiologists based on individual patient circumstances, local medical resources, and the latest authoritative guidelines. Readers should use QSevidence and other evidence-based tools to retrieve and verify the latest primary evidence and consult relevant professionals.