Incidence and related factors for intraoperative failed spinal anaesthesia for lower limb arthroplasty

Failed Spinal Anesthesia: Incidence and Associated Factors

Introduction Spinal anesthesia, a commonly used technique for lower abdominal, pelvic, and lower extremity surgeries, involves injecting a local anesthetic into the subarachnoid space to temporarily block sensory, motor, and sympathetic nerves. Despite its high success rate, the failure of spinal anesthesia, which can lead to adverse patient outcomes, remains a concern. The failure rate varies widely, from 1% to 17%, influenced by factors such as technical challenges, patient anatomy, and practitioner experience. This study aims to determine the incidence and causes of spinal anesthesia failure in a university hospital setting. Methodology This cross-sectional, prospective observational study was conducted at Dr. D.Y. Patil Medical College and Research Centre, Pimpri, Pune. Data were collected from patients aged ≥18 years who underwent spinal anesthesia over one year. The study recorded various parameters, including patient demographics, surgical details, and anesthetic techniques. Failed spinal anesthesia was categorized into total failure (no block achieved) and partial failure (need for additional analgesia). Statistical analysis was performed to identify the incidence and contributing factors to spinal anesthesia failure. Results Out of 3933 patients receiving spinal anesthesia, 72 experienced failure, resulting in an incidence rate of 1.83%. The majority of failures were total (87.5%), with partial failures accounting for 12.5%. Among the cases of failed spinal anesthesia, failures were most common in obstetric surgeries (37.5%), followed by orthopedic (25%), general (22.22%), and urologic (15.28%) surgeries. The highest failure rate according to surgery type in all patients receiving spinal anesthesia was seen in orthopedic surgery (3.46%) followed by urologic surgery (2.17%). Elective surgeries had a lower failure rate (1.39%) compared to emergency surgeries (3.87%). Quincke-type needles were predominantly used, and spinal anesthesia was most often administered at the L3-L4 intervertebral space in the sitting position. Notably, first-year residents had the highest failure rate (43.06%), while more experienced practitioners had lower failure rates. Conclusion The incidence of spinal anesthesia failure in our study was 1.83%, with total failures being more common than partial failures. Factors such as surgical type, emergency status, and practitioner experience can impact the failure rate. The higher failure rate among less experienced practitioners underscores the need for improved training and expertise. Regular monitoring and refinement of spinal anesthesia techniques are essential to enhance patient safety and optimize anesthetic care.

Is a Failed Spinal Attempt Associated With a Worse Clinical Course Following Primary Total Hip and Knee Arthroplasty?

BACKGROUND

Spinal anesthesia (SA) is the preferred anesthesia modality for total joint arthroplasty (TJA). However, studies establishing SA as preferential may be subject to selection bias given that general anesthesia (GA) is often selectively utilized on more difficult, higher-risk operations. The optimal comparison group, therefore, is the patient converted to GA due to a failed attempt at SA. The purpose of this study was to determine risk factors and outcomes following failed SA with conversion to GA during primary total hip arthroplasty (THA) or total knee arthroplasty (TKA).

METHODS

A consecutive cohort of 4,483 patients who underwent primary TJA at our institution was identified (2,004 THA and 2,479 TKA). Of these patients, 3,307 underwent GA (73.8%), 1,056 underwent SA (23.3%), and 130 patients failed SA with conversion to GA (2.90%). Primary outcomes included rescue analgesia requirement in the postanesthesia care unit (PACU), time to ambulation, pain scores in the PACU, estimated blood loss, and 90-day complications.

RESULTS

Risk factors for SA failure included older age and a higher comorbidity burden. Failure of SA was associated with increased estimated blood loss, rescue intravenous opioid use, and time to ambulation when compared to the successful SA group in both THA and TKA patients (P < .001). The anesthesia modality was not associated with significant differences in PACU pain scores. The 90-day complication rate was similar between the failed SA and GA groups. There was a higher incidence of postoperative pain prompting unplanned visits and thromboembolism when comparing failed SA to successful SA in both THA and TKA patients (P < .05).

CONCLUSIONS

In our series, patients who had failed SA demonstrated inferior outcomes to patients receiving successful SA and similar outcomes to patients receiving GA who did not have an SA attempt. This emphasizes the importance of success in the initial attempt at SA for optimizing outcomes following TJA.

Inadequate Spinal Anesthesia in Lumbar Spine Surgery Is Related to Volume of the Thecal Sac

BACKGROUND

Spinal anesthesia (SA) is used in lumbar surgery, but initial adequate analgesia fails in some patients. In these cases, spinal redosing or conversion to general endotracheal anesthesia is required, both of which are detrimental to the patient experience and surgical workflow.

METHODS

We reviewed cases of lumbar surgery performed under SA from 2017-2021. We identified 12 cases of inadequate first dose and then selected 36 random patients as controls. We used a measurement tool to approximate the volume of the dural sac for each patient using T2-weighted sagittal magnetic resonance imaging sequences.

RESULTS

Patients who had an inadequate first dose of anesthesia had a significantly larger dural sac volume, 22.8 ± 7.9 cm3 in the inadequate dose group and 17.4 ± 4.7 cm3 in controls (P = 0.043). The inadequate dose group was significantly younger, 54.2 ± 8.8 years in failed first dose and 66.4 ± 11.9 years in controls (P = 0.001). The groups did not differ by surgical procedure (P = 0.238), level (P = 0.353), American Society of Anesthesia score (P = 0.546), or comorbidities.

CONCLUSIONS

We found that age, larger height, and dural sac volume are risk factors for an inadequate first dose of SA. The availability of spinal magnetic resonance imaging in patients undergoing spine surgery allows the preoperative measurement of their thecal sac size. In the future, these data may be used to personalize spinal anesthesia dosing on the basis of individual anatomic variables and potentially reduce the incidence of failed spinal anesthesia in spine surgery.

Incidence and factors associated with failed spinal anaesthesia among patients undergoing surgery: a multi- center prospective observational study

BACKGROUND

Failed spinal anaesthesia causes prolonging of operation time, insufficient analgesia for surgery and needs repeating spinal anaesthesia which in turn causes local anaesthesia toxicity, high spinal and total spinal, and conversion to general anaesthesia. However, the problem remains unexplored in Amhara regional state comprehensive specialized hospitals.

OBJECTIVE

To determine incidence and factors associated with failed spinal anaesthesia among patients undergoing surgery in selected Amhara National Regional State comprehensive specialized hospitals, Northwest Ethiopia, 2023.

METHODS

Multi-center prospective observational study was conducted. Data was collected using questionnaire and checklist. All consecutive scheduled emergency and elective patients were included in the study. Data was transformed from Epi data to SPSS and logistic regression analysis was done. Both crude and adjusted odds ratio were used to assess the strength of association. Variables with a p-value of less than 0.05 were considered as statistically significant.

RESULTS

A total of 532 patients were included in this study with a response rate of 98%. Incidence of failed spinal anaesthesia was 22.4% (CI = 19-25.9). Emergency surgery (AOR = 7.01, CI = 4.5-12.7), dose of bupivacaine of ≤ 10 mg (AOR = 3.02, CI = 1.3-10.2), work experience of anaesthetist < 2 years (AOR = 3.1, CI = 1.7-5.72), bloody CSF (AOR = 8.5, CI = 2.53-18.5), hyperbaric local anaesthetic drug (AOR = 3.3, 95% CI = 3.2-8.2) and local anaesthetist without adjuvants (AOR = 5.25, CI = 2.62-14.2) were associated failed spinal anaesthesia.

CONCLUSION AND RECOMMENDATION

The incidence of failed spinal anaesthesia was high in Amhara Region comprehensive specialized hospitals. We suggest that anaesthesia providers should minimize failure by using adjuvants and appropriate dose of local anaesthetic. Additionally, simulation training should be given for anaesthesia trainees to improve their skills and to produce competent professionals.

The Relationship of Spinal Anesthesia Dosing Based on Thecal Sac Area to Anesthetic Failure in Lumbar Surgery

BACKGROUND AND OBJECTIVES

Greater thecal sac volumes are associated with an increased risk of spinal anesthesia (SA) failure. The thecal sac cross-sectional area accurately predicts thecal sac volume. The thecal sac area may be used to adjust the dose and prevent anesthetic failure. We aim to assess the rate of SA failure in a prospective cohort of lumbar surgery patients who receive an individualized dose of bupivacaine based on preoperative measurement of their thecal sac area.

METHODS

A total of 80 patients prospectively received lumbar spine surgery under SA at a single academic center (2022-2023). Before surgery, the cross-sectional area of the thecal sac was measured at the planned level of SA injection using T2-weighted MRI. Patients with an area <175 mm2, equal to or between 175 and 225 mm2, and >225 mm2 received an SA injection of 15, 20, or 25 mg of 0.5% isobaric bupivacaine, respectively. Instances of anesthetic failure and adverse outcomes were noted. Incidence of SA failure was compared with a retrospectively obtained control cohort of 250 patients (2019-2022) who received the standard 15 mg of bupivacaine.

RESULTS

No patients in the individualized dose cohort experienced failure of SA compared with 14 patients (5.6%) who experienced failure in the control cohort (P = .0259). The average thecal sac area was 187.49 mm2, and a total 28 patients received 15 mg of bupivacaine, 42 patients received 20 mg of bupivacaine, and 10 patients received 25 mg of bupivacaine. None of the patients experienced any adverse outcomes associated with SA. Patients in the individualized dose cohort and control cohort were comparable and had a similar distribution of lumbar procedures and comorbidities.

CONCLUSION

Adjusting the dose of SA according to thecal sac area significantly reduces the rate of SA failure in patients undergoing lumbar spine surgery.

Type, management, and associated factors of failed spinal anesthesia in cesarean section. Prospective cohort study

Background

Spinal anesthesia is an anesthesia technique suitable for cesarean section to avoid respiratory complications. However, the management of spinal anesthesia is very important because spinal anesthesia may fail and the patient may be exposed to pain and discomfort.

Objective

To assess the type, management, and related factors of failure of spinal anesthesia at cesarean section.

Methods

Multicenter prospective cohort study was conducted at a public hospital in Addis Ababa on 794 mothers who met the criteria for cesarean section under spinal anesthesia. Data collection methods were adopted, including chart reviews and observations of spinal anesthesia procedures. The data collected was entered in Epi info version 7 and analyzed in SPSS version 20. Independent variables with dependent variables were analyzed using logistic regression. A p-value of 0.05 for & it; was considered a statistically significant test cutoff.

Result

Of 121 failed spinal anesthesia 35 were complete and 86 were partial failed spinal anesthesia from those complete failed spinal anesthesia were managed by repeating spinal and converting to general anesthesia and partial failed spinal anesthesia were managed by the supplementary drug. Experience of the anesthetist <1 (AOR = 4.12, 95% CI, 2.47-6.90), patient position (AOR = 14.43,95%CL, 2.65-78.61), number of attempts>1 (AOR = 9.26, 95% CI, 5.69-15.01), bloody CSF (AOR = 6.37, 95%CI, 2.90-13.96), BMI ≥30kgm2 (AOR = 2.03, 95%CI, 1.12-3.68) and dose of bupivacaine <10 mg (AOR = 2.72, 95% CI, 1.33-5.53) were found to be statistically significant associated with failed spinal anesthesia.

Conclusion and recommendation

Experience of anesthetists (<1 year), obesity, bupivacaine dose <10 mg, bloody appearance of CSF, number of attempts> 1 were associated factors for failed spinal anesthesia in cesarean section. Our failed spinal management is not the same among hospitals and does not follow recommended failed spinal management. Up-skilling of anesthesia professionals should be considered on identified associated factors of failed spinal anesthesia and management of failed spinal anesthesia should be based on the recommended guidelines.

Evaluation Effect of Aspiration of 0.2 ml of Cerebrospinal Fluid After Completion of Injection 0.5% Bupivacaine and Reinjection Into Subarachnoid Space on Sensory and Motor Block in Cesarean Section: A Randomized Clinical Trial

Background

Spinal anesthesia (SPA) is the most common type of anesthesia administered for cesarean section. The main aim of this study was to evaluate the effect of aspiration of CSF (0.2 mL) immediately after SPA with hyperbaric 0.5% bupivacaine on the extent of sensory and motor block.

Methods

In this clinical trial, 60 women at ≥37 weeks of gestation and aged between 18 and 46 years, candidate for cesarean delivery under spinal anesthesia were randomly allocated into two equal groups (n = 30). Group A (CSF-aspiration group) received the spinal anesthesia with 10 mg of hyperbaric 0.5% bupivacaine with aspiration of 0.2 ml of CSF. Group B (no-CSF-aspiration group) received only 10 mg of 0.5% hyperbaric bupivacaine. Pin-prick analgesia and motor block were tested during the induction.

Results

The mean maximum level of analgesia was T6 in each group. Although the mean time to reach the maximum level of anesthesia (4.43 ± 5.14 vs. 2.76 ± 2.04, P = 0.107) and to reach T10 level (50.56 ± 11.51 vs. 49.10 ± 13.68, P = 0.665) in the CSF-aspiration group is longer than the non-CSF-aspiration group, but this differences were not significant. There were no significant between-group differences regarding sensory and motor block quality (P = 0.389) or failed SPA (four cases in CSF-aspiration group vs. two cases in no-CSF-aspiration group, P = 0.389). The incidence of bradycardia, hypotension, headache, vomiting and nausea were similar in both groups (P > 0.05). In addition, the difference in hemodynamic parameters between the two groups over times was not statistically significant.

Conclusion

Our finding indicated that the aspiration of 0.2 ml of CSF after injection of spinal anesthesia with hyperbaric 0.5% bupivacaine does not seem to affect the extent of sensory and motor block, success rate, or outcome after SPA in cesarean section.

Clinical Trial Registration

[https://www.irct.ir/search/result?query=IRCT20120915010841N25], identifier [IRCT20120915010841N25].

Waking Up in Pain: a prospective unselected cohort study of pain in 3702 patients immediately after surgery in the Danish Realm

BACKGROUND

Acute and persistent pain after surgery is well described. However, no large-scale studies on immediate postoperative pain in the operating room (OR) exist, hindering potential areas of research to improve clinical outcomes. Thus, we aimed to describe the occurrence and severity of immediate postoperative pain in a large, unselected cohort.

METHODS

This was a prospective cohort study, encompassing all procedures in 31 public hospitals in the Danish Realm, during a 5-day period including the weekend. Data on procedures and anesthesia were collected and the main outcome was occurrence of moderate or severe pain in the OR. Secondary outcomes included pain, sedation and nausea in the OR or during the first 15 min in the postanesthesia care unit (PACU) including relevant risk factors. Descriptive and logistic regression statistics were used.

RESULTS

A total of 3675 procedures were included for analysis (87% inclusion rate). Moderate or severe pain occurred in 7.4% (95% CI 6.5% to 8.3%) of cases in the OR immediately after awakening, rising to 20.2% in the OR and/or PACU. Large intraprocedure and interprocedure variations occurred (0.0%-37.5%), and in 20% of cases with epidural-general anesthesia patients experienced moderate or severe pain. Independent risk factors were female sex, younger age, preoperative pain, daily opioid use and major surgical procedures.

CONCLUSION

Moderate or severe pain in the immediate postoperative phase occurred in 20% of all cases with procedure and anesthesiological technique variations, suggesting a need for identification of relevant procedure-specific risk factors and development of preventive treatments.

TRIAL REGISTRATION NUMBER

RoPR ID 43191.

The Anaesthetic Biobank of Cerebrospinal fluid: a unique repository for neuroscientific biomarker research

Background

The pathophysiology of numerous central nervous system disorders remains poorly understood. Biomarker research using cerebrospinal fluid (CSF) is a promising way to illuminate the neurobiology of neuropsychiatric disorders. CSF biomarker studies performed so far generally included patients with neurodegenerative diseases without an adequate control group. The Anaesthetic Biobank of Cerebrospinal fluid (ABC) was established to address this. The aims are to (I) provide healthy-control reference values for CSF-based biomarkers, and (II) to investigate associations between CSF-based candidate biomarkers and neuropsychiatric symptoms.

Methods

In this cross-sectional study, we collect and store CSF and blood from adult patients undergoing spinal anaesthesia for elective surgery. Blood (20.5 mL) is collected during intravenous cannulation and CSF (10 mL) is aspirated prior to intrathecal local anaesthetic injection. A portion of the blood and CSF is sent for routine laboratory analyses, the remaining material is stored at -80 °C. Relevant clinical, surgical and anaesthetic data are registered. A neurological examination and Montreal Cognitive Assessment (MoCA) are performed pre-operatively and a subset of patients fill in questionnaires on somatic and mental health (depression, anxiety and stress).

Results

Four-hundred-fifty patients (58% male; median age: 56 years) have been enrolled in the ABC. The planned spinal anaesthetic procedure was not attempted for various reasons in eleven patients, in fourteen patients the spinal puncture failed and in twelve patients CSF aspiration was unsuccessful. A mean of 9.3 mL CSF was obtained in the remaining 413 of patients. Most patients had a minor medical history and 60% scored in the normal range on the MoCA (median score: 26).

Conclusions

The ABC is an ongoing biobanking project that can contribute to CSF-based biomarker research. The large sample size with constant sampling methods and extensive patient phenotyping provide excellent conditions for future neuroscientific research.

Spinal anesthesia in a designated block bay for total joint arthroplasty: improving operating room efficiency

Background

Creating highly efficient operating room (OR) protocols for total joint arthroplasty (TJA) is a challenging and multifactorial process. We evaluated whether spinal anesthesia in a designated block bay (BBSA) would reduce time to incision, improve first case start time and decrease conversion to general anesthesia (GA).

Methods

Retrospective cohort study on the first 86 TJA cases with BBSA from April to December 2018, compared with 344 TJA cases with spinal anesthesia performed in the OR (ORSA) during the same period. All TJA cases were included if the anesthetic plan was for spinal anesthesia. Patients were excluded if circumstances delayed start time or time to incision (advanced vascular access, pacemaker interrogation, surgeon availability). Data were extracted and analyzed via a linear mixed effects model to compare time to incision, via a Wilcoxon rank-sum test to compare first case start time, and via a Fisher’s exact test to compare conversion to GA between the groups.

Results

In the mixed effect model, the BBSA group time to incision was 5.37 min less than the ORSA group (p=0.018). The BBSA group had improved median first case start time (30.0 min) versus the ORSA group (40.5 min, p<0.0001). There was lower conversion to GA 2/86 (2.33%) in the BBSA group versus 36/344 (10.47%) in the ORSA group (p=0.018). No serious adverse events were noted in either group.

Conclusions

BBSA had limited impact on time to incision for TJA, with a small decrease for single OR days and no improvement on OR days with two rooms. BBSA was associated with improved first case start time and decreased rate of conversion to GA. Further research is needed to identify how BBSA affects the efficiency of TJA.

Incidence and Causes of Failed Spinal Anesthesia

Introduction: Spinal anesthesia (SA) is one of the most frequently applied anesthesia procedures today. However, SA failure rate varies between 1 and 17%. The age of the patient, the position at which the procedure is performed, or the characteristics of the technical operation can affect success. In this study, we aimed to compare the most frequent SA failures according to the types of surgery and causes of failure. The results of SA procedures performed in a university hospital were compare to those published in the current literature. Materials and Methods: After obtaining ethics committee ­approval for our study, the hospital archives were examined retrospectively for 1 year with respect to SA procedures. SA application and failure rates were examined. Three or more SA attempts, failed dural puncture, or unsuccessful injection, and anesthesia applications that did not provide sufficient sensory block for surgery despite successful drug treatment were defined as failure. Results: Of all anesthesia procedures, SA was applied at a rate of 23.5%. Our SA failure rate was calculated as 16.6%. Considering a single surgical procedure, obstetric anesthesia was the most common surgery with failed SA (28.7%). The most common cause of failure was insufficient analgesia (32.9%). Discussion: SA failure rates were observed to be in a variable distribution range in the literature, and in some studies, SA failure was defined as a block that did not occur despite a full dose and successful injection, and this rate was found to be 3.9%. The high rate in our study group may be explained by differences in the definition of SA: blocks performed with several trials and any block that could not be applied were also recorded as SA failure. The reasons for failing to apply this procedure is an issue that is worth examining also in terms of patient satisfaction and safety, which is an important issue. Conclusion: Although the definition of unsuccessful SA is confusing, SA failure rates are worth examining and improving for each hospital.

Using chloroprocaine for spinal anaesthesia in outpatient knee-arthroscopy results in earlier discharge and improved operating room efficiency compared to mepivacaine and prilocaine

PURPOSE

Knee arthroscopies are regularly carried out in an outpatient setting. The purpose of this retrospective analysis was to investigate the impact of different local anaesthetics for spinal anaesthesia on operating room efficiency (perioperative process times) and postoperative recovery. This study aims to determine the optimal LA for SPA in patients undergoing knee arthroscopy at a day-surgery centre.

METHODS

Anaesthesia records of all patients undergoing knee arthroscopy under spinal anaesthesia from 2010 until 2017 were analysed. Patients were categorised as having received spinal anaesthesia with prilocaine, mepivacaine or chloroprocaine.

RESULTS

Three-hundred and nine patients were included. Postoperative recovery was significantly faster for chloroprocaine 1% compared with both other local anaesthetics regarding all stages of recovery until discharge. Perioperative processes and surgery time were significantly shorter when chloroprocaine was used. Early postoperative pain occurred more frequently and earlier after spinal anaesthesia with chloroprocaine. Nevertheless, pain intensity did not differ between groups.

CONCLUSION

Spinal anaesthesia provides reliable blocks for outpatient knee arthroscopy. Considerations on the choice of local anaesthetic for spinal anaesthesia must include not only the recovery profile, but also the impact on operating room efficiency. Due to a superior recovery profile, low incidences of adverse side effects and raised operating room efficiency, chloroprocaine is the recommendable local anaesthetic for spinal anaesthesia in patients undergoing knee arthroscopy in an ambulatory setting. Since the frequency of SPA in patients undergoing outpatient knee arthroscopy is rising yearly, the results of this study are of high clinical relevance. The use of chloroprocaine leads to improved recovery, optimized perioperative processes and consecutively to a raised OR efficiency.

LEVEL OF EVIDENCE

III.

Retrospective analysis of mepivacaine, prilocaine and chloroprocaine for low-dose spinal anaesthesia in outpatient perianal procedures

PURPOSE

Perianal procedures are carried out in an outpatient setting regularly. The purpose of this retrospective analysis was to investigate the impact of different local anaesthetics (LA) for spinal anaesthesia (SPA) on operating room (OR) efficiency (perioperative process times, turnaround times) and postoperative recovery. This study aims on the determination of the optimal LA for low-dose SPA in the specific setting of a high-volume day-surgery centre.

METHODS

Anaesthesia records of all patients undergoing perianal outpatient surgery under saddle-block SPA at the Mannheim University Medical Centre from 2008 until 2017 were analysed. Patients were categorized as having received prilocaine, mepivacaine or chloroprocaine.

RESULTS

Two thousand seven hundred forty-six patients were included. Postoperative recovery was faster for chloroprocaine 1% compared with both other LAs. Preoperative processes but not process times in the OR were shorter for chloroprocaine. In contrary, turnaround times were significantly prolonged when chloroprocaine had been used, leading to reduction of OR efficiency.

CONCLUSION

Low-dose SPA provides reliable blocks for perianal surgery. Considerations on the choice of LA for SPA must include not only the recovery profile, but also the impact on OR efficiency. Due to shorter turnaround times and a manageable prolonged duration of stay, prilocaine is the preferable LA for low-dose SPA in perianal outpatient surgery at a high-volume day-surgery centre.