End-tidal carbon dioxide monitoring stabilized hemodynamic changes during ECT

Effect of C-Clamp Application on Hemodynamic Instability in Polytrauma Victims with Pelvic Fracture

Background and Objectives: C-clamp application may reduce mortality in patients with unstable pelvic fractures and hemodynamic instability. Decreasing C-clamp use over the past decades may have resulted from concerns about its effectiveness and safety. The purpose of this study was to document effective hemodynamic stabilization after C-clamp application by means of vital parameters (primary outcome parameter), and the subsequent effect on metabolic indices and volume management (secondary outcome parameters). Materials and Methods: C-clamp application was performed between 2014 and 2021 for n = 13 patients (50 ± 18 years) with unstable pelvic fractures and hemodynamic instability. Vital parameters, metabolic indices, volume management, and the correlation of factors and potential changes were analyzed. Results: After C-clamp application, increases were measured in systolic blood pressure (+15 mmHg; p = 0.0284) and mean arterial pressure (+12 mmHg; p = 0.0157), and a reduction of volume requirements (p = 0.0266) and bolus vasoactive medication needs (p = 0.0081) were observed. The earlier C-clamp application was performed, the greater the effect (p < 0.05; r > 0.6). Heart rate, shock index, and end-tidal CO2 were not significantly altered. The extent of base deficit, hemoglobin, and lactate did not correlate with changes in vital parameters. Conclusions: In the majority of hemodynamically unstable trauma patients not responding to initial fluid resuscitation and severe pelvic fracture, early C-clamp application had an additive effect on hemodynamic stabilization and reduction in volume substitution. Based on these findings, there is still a rationale for considering early C-clamp stabilization in this group of severely injured patients.

Prevention of Oxygen Desaturation in Morbidly Obese Patients During Electroconvulsive Therapy: A Narrative Review

In general, preoxygenation is performed using a face mask with oxygen in a supine position, and oxygenation is maintained with manual mask ventilation during electroconvulsive therapy (ECT). However, hypoxic episodes during ECT are not uncommon with this conventional method, especially in morbidly obese patients. The most important property of ventilatory mechanics in patients with obesity is reduced functional residual capacity (FRC). Thus, increasing FRC and oxygen reserves is an important step to improve oxygenation and prevent oxygen desaturation in these individuals. Head-up position, use of apneic oxygenation, noninvasive positive pressure ventilation, and high-flow nasal cannula help increase FRC and oxygen reserves, resulting in improved oxygenation and prolonged safe apnea period. Furthermore, significantly higher incidence of difficult mask ventilation is common in morbidly obese individuals. Supraglottic airway devices establish effective ventilation in patients with difficult airways. Thus, the use of supraglottic airway devices is strongly recommended in these patients. Conversely, because muscle fasciculation induced by depolarizing neuromuscular blocking agents markedly increases oxygen consumption, especially in individuals with obesity, the use of nondepolarizing neuromuscular blocking agents may contribute to better oxygenation in morbidly obese patients during ECT.

Modified Anesthesia Protocol for Electroconvulsive Therapy Permits Reduction in Aerosol-Generating Bag-Mask Ventilation during the COVID-19 Pandemic

INTRODUCTION

Electroconvulsive therapy (ECT) is a critical procedure in psychiatric treatment, but as typically delivered involves the use of bag-mask ventilation (BMV), which during the COVID-19 pandemic exposes patients and treatment staff to potentially infectious aerosols.

OBJECTIVE

To demonstrate the utility of a modified anesthesia protocol for ECT utilizing preoxygenation by facemask and withholding the use of BMV for only those patients who desaturate during the apneic period.

METHODS

This chart review study analyzes patients who were treated with ECT using both the traditional and modified anesthesia protocols.

RESULTS

A total of 106 patients were analyzed, of whom 51 (48.1%) required BMV using the new protocol. Of clinical factors, only patient BMI was significantly associated with the requirement for BMV. Mean seizure duration reduced from 52.0 ± 22.4 to 46.6 ± 17.1 s, but seizure duration was adequate in all cases. No acute physical, respiratory, or psychiatric complications occurred during treatment.

CONCLUSIONS

A modified anesthesia protocol reduces the use of BMV by more than 50%, while retaining adequate seizure duration.

Adjustment of Anaesthesia Depth Using Bispectral Index Prolongs Seizure Duration in Electroconvulsive Therapy

Electroconvulsive therapy (ECT) under propofol anaesthesia induces relatively shorter seizures compared to barbiturate anaesthesia. Since significant correlation between seizure duration and bispectral index (BIS) value immediately before electrical stimulus has been reported among patients, adjustment of anaesthesia depth as determined by BIS may be effective in obtaining a longer seizure length. In the present study, we examined this hypothesis in those patients whose muscular seizure duration was less than 40s.

ECT was prescribed to 20 patients suffering from endogenous depression. General anaesthesia was induced with propofol 1 mg/kg. Succinylcholine chloride 1 mg/kg was then given. The efficacy of electrical stimulation was determined using a tourniquet technique, electromyogram, and electroencephalography. When a patient had a seizure less than 40s in their second ECT treatment, the subsequent treatment was modified such that the electrical stimulus was given after waiting for a higher BIS value (+10-20). Intensity of electrical stimulus and anaesthesia conditions were identical in the two treatments.

All 20 patients had longer seizures as determined by the electromyogram and/or electroencephalography when the stimulus was delivered at the higher BIS value. Seizure duration measured by muscle movement was 31±5s when the stimulus was delivered without waiting and 46±10s when delivered after waiting. There was a significant difference in seizure duration between the two treatments (P<0.01).

Waiting for a recovery in BIS value before electrical stimulation can prolong seizure duration.

Changes in cardiac autonomic nervous system activity during a course of electroconvulsive therapy

AIM

Although electroencephalogram (EEG) seizure duration and seizure threshold change during a course of electroconvulsive therapy, the mechanisms by which these factors influence heart rate during subsequent electroconvulsive therapy sessions are currently unclear. In the current study, we investigated changes in heart rate during electroconvulsive therapy.

METHODS

We recorded electroencephalography and electrocardiography during electroconvulsive therapy in 12 patients with major depressive disorder. Baseline heart rate was defined as the mean heart rate in the 30 seconds prior to stimulus onset. The Time_Max peak refers to the maximum heart rate after stimulus onset. Time_1/2 points represent the time points at which the heart rate had decreased to a value midway between the baseline heart rate and the Time_Max peak. We examined the relationships between EEG seizure duration, Time_Max , and Time_1/2 throughout the course of electroconvulsive therapy.

RESULTS

Time_1/2 decreased as the number of electroconvulsive sessions increased. Time_1/2 was positively correlated with EEG seizure duration.

CONCLUSION

The duration in which electroconvulsive therapy-induced sympathetic nervous system activation returned halfway to baseline levels gradually shortened during the course of electroconvulsive therapy.

Hyperventilation and electroconvulsive therapy: A literature review

BACKGROUND

Hyperventilation has been proposed as an augmentation strategy in electroconvulsive therapy (ECT) in accordance with its proconvulsant effect.

OBJECTIVE

This study reviews the existing literature on the application of hyperventilation in ECT, its efficacy, and tolerance.

METHODS

A systematic search was performed in PubMed and EMBASE databases. Search terms ('electroconvulsive therapy' and 'hyperventilation', 'ventilation', 'hyperoxygenation', 'hyperoxia', 'hypocapnia') were used to retrieve works from 1966 to June 2016. Works that described hyperventilation manoeuvres in ECT settings and their clinical repercussion were included in the review.

RESULTS

A total of 17 observational and experimental studies were selected. An important heterogeneity in study designs, samples and ECT conditions, was detected. Findings support a positive influence of hyperventilation on seizure duration, which is the main study variable across different works. Effects of hyperventilation on seizure threshold and quality parameters have been less thoroughly studied. Systematic recording of clinical outcomes and adverse effects of hyperventilation is uncommon.

CONCLUSIONS

The literature suggests that hyperventilation may be an effective and safe technique to enhance ECT, but many aspects remain to be studied. Further investigations, especially controlled clinical trials, are necessary and should result in a specific and reliable hyperventilation protocol for ECT settings.

Protocolized hyperventilation enhances electroconvulsive therapy

BACKGROUND

Hyperventilation is recommended in electroconvulsive therapy (ECT) to enhance seizures and to increase patients' safety. However, more evidence is needed regarding its effects and the optimum method of application.

METHODS

This prospective study involving 21 subjects compared two procedures, protocolized hyperventilation (PHV) and hyperventilation as usual (HVau), applied to the same patient in two consecutive sessions. Transcutaneous partial pressure of carbon dioxide (TcPCO₂) was measured throughout all sessions. Ventilation parameters, hemodynamic measures, seizure characteristics, and side effects were also explored.

RESULTS

PHV resulted in lower TcPCO₂ after hyperventilation (p=.008) and over the whole session (p=.035). The lowest TcPCO₂ was achieved after voluntary hyperventilation. Changes in TcPCO₂ from baseline showed differences between HVau and PHV at each session time-point (all p<.05). Between- and within-subjects factors were statistically significant in a general linear model. Seizure duration was greater in PHV sessions (p=.028), without differences in other seizure quality parameters or adverse effects. Correlations were found between hypocapnia induction and seizure quality indexes.

LIMITATIONS

Secondary outcomes could be underpowered.

CONCLUSIONS

PHV produces hypocapnia before the stimulus, modifies patients' TcPCO₂ values throughout the ECT session and lengthens seizure duration. Voluntary hyperventilation is the most important part of the PHV procedure with respect to achieving hypocapnia. A specific ventilation approach, CO₂ quantification and monitoring may be advisable in ECT. PHV is easy to apply in daily clinical practice and does not imply added costs. Ventilation management has promising effects in terms of optimizing ECT technique.

Hypocapnia and hyperoxia induction using a hyperventilation protocol in electroconvulsive therapy

INTRODUCTION

Hyperventilation in electroconvulsive therapy sessions has been associated with seizure threshold, seizure characteristics, and cognitive effects. There is no consensus on the optimal procedure of applying hyperventilation manoeuvres during electroconvulsive therapy.

MATERIAL AND METHODS

Prospective evaluation of the effects of systematic use of hyperventilation manoeuvres with facial mask and capnography (protocolized hyperventilation [pHV]), on ventilation parameters and on seizures. The study included a sample of 130 sessions (65 performed according to hyperventilation standard practice and 65 successive sessions, with pHV) of 35 patients over a period of 10 weeks.

RESULTS

The pHV manoeuvres reduced exhaled CO₂ and increased O₂ saturation significantly (P<.001). The average CO₂ reduction achieved was 6.52±4.75mmHg (95% CI -7.7 to -5.3). The CO₂ values after pHV correlated significantly with seizure duration and O₂ values, with other electroencephalographic quality indices. In pHV sessions, compared with sessions performed according to hyperventilation standard practice, the average lengthening of the motor and electroencephalographic seizure was 3.86±14.62 and 4.73±13.95s, respectively. No differences were identified in other ictal quality parameters.

CONCLUSIONS

The proposed pHV manoeuvres significantly modify ventilation parameters. The hypocapnia and hyperoxia obtained by applying these manoeuvres lengthen the duration of seizures without worsening the quality of the electroencephalographic trace. The use of pHV is generalisable and might improve electroconvulsive therapy procedure without adding costs.

Electroconvulsive therapy anesthesia practice patterns: results of a UK postal survey

OBJECTIVE

To review anesthesia practice patterns associated with electroconvulsive therapy (ECT) in the UK.

METHODS

A 12-item questionnaire survey on the practice of ECT anesthesia was sent to all units in the UK identified as providing ECT services.

RESULTS

One hundred thirty active ECT units were identified. Sixty-six (51%) responded. Forty-five percent of respondents worked in units located within acute hospital boundaries and 53% outside acute hospital boundaries. Forty-seven percent of respondents were associated with units providing consultant anesthetic cover for 75-100% of ECT sessions. Twenty-seven percent of the units did not use capnography, 17% did not use continuous electrocardiography, and 16% did not use noninvasive blood pressure monitoring.

LIMITATIONS

Results were entirely from respondents. No practices were directly observed.

CONCLUSIONS

Although there is apparent widespread recognition of ECT Accreditation Service guidelines, compliance with recommended standards is variable. Given the typically high comorbidity of ECT patients, and indications of elevated anesthetic risk from non-UK studies, this has important implications for the safety of ECT anesthesia in the UK.

How is electrocardiogram influenced by electroconvulsive therapy in males and females?

OBJECTIVES

We aimed to investigate and compare the P duration and P dispersion (Pd) between male and female patients with a primary diagnosis of chronic schizophrenia disorder before and after the electroconvulsive therapy (ECT) period.

METHODS

We obtained electrocardiograms of 50 healthy young volunteers which included 25 female (group F, n = 25) and 25 male patients (group M, n = 25). We measured minimum and maximum P wave durations (Pmin, Pmax) and Pd in milliseconds. Electrocardiography was performed before electroconvulsive therapy (ECT) and immediately after the ECT period after awakening. A 12-lead surface electrocardiogram was obtained from each subject in the supine position.

RESULTS

The post-ECT P duration was significantly longer than the pre-ECT P duration in groups F and M (P = 0.01 and P = 0.008, respectively). The post-ECT Pd was significantly longer than the pre-ECT Pd in groups F and M (P = 0.0001 in both groups). A higher correlation (r) in group M was observed between the pre-ECT Pd and post-ECT P duration than in group F (r = 0.538, P = 006 in group M; r = 0.349, P = 08 in group F). There was no significant difference between the groups regarding hemodynamics.

CONCLUSIONS

Electroconvulsive therapy in both sexes may influence atrial conduction as evidenced by the significantly prolonged Pmax and Pd in patients with a primary diagnosis of schizophrenia disorder.

Critical monitoring issues outside the operating room

There is no need to reinvent the wheel to determine the need for vigilant monitoring in outside of the operating room (OOR) settings. Anesthesiologists have evolved a robust system of monitoring standards based on decades of experience in operating room environments. Every OOR location should be thoroughly evaluated and monitoring standards implemented. The standards should be periodically reviewed to avert morbidity.

Carbon dioxide exhalation temporarily increases during electroconvulsive therapy

Electroconvulsive therapy induces hypermetabolism and elevates oxygen and energy demands, while more carbon dioxide is produced than usual. The purpose of the present study was to determine the elevated carbon dioxide exhalation and the adequate ventilation volume during electroconvulsive therapy. Carbon dioxide exhalation during an electrically induced seizure was continuously monitored by capnography and spirography in 15 patients with endogenous depression. A laryngeal mask airway was used to measure the airway gas flow. Data were collected during a total of 80 electroconvulsive therapy trials. The carbon dioxide exhalation at 1 min after electrical stimulation was higher than the control value (2.8 +/- 0.4 versus 2.3 +/- 0.3 ml.min(-1).kg(-1), mean +/- SD; P < 0.05). The ventilation volume was increased for 3 min after the electrical stimulation to maintain the end-tidal carbon dioxide partial pressure at 35-40 mmHg. The results showed that increasing the ventilation volume by approximately 20% may be necessary to compensate for the increased carbon dioxide exhalation during electroconvulsive therapy.

Benefits of the laryngeal mask for airway management during electroconvulsive therapy

Accumulation of carbon dioxide (CO2) can disturb systemic hemodynamics and increase the seizure threshold in patients receiving electroconvulsive therapy (ECT). The purpose of this study was to investigate the effects of the laryngeal mask on blood gas, hemodynamics, and seizure duration during ECT under propofol anesthesia. Ventilation was assisted using either a face mask (n=23) or laryngeal mask (n=23) and 100% oxygen. There was no significant difference in PaO2 between the two groups. PaCO2 was greater in the face mask group than the laryngeal mask group at 3 minutes (54 +/- 11 mm Hg, 41 +/- 8 mm Hg, respectively) and 5 minutes (52 +/- 11 mm Hg, 43 +/- 15 mm Hg, respectively) after electrical stimulation (p<0.01). Mean blood pressure was higher than the corresponding preanesthesia value at 1 to 5 minutes after electrical stimulation in the face mask group and at 1 to 3 minutes after electrical stimulation in the laryngeal mask group. Mean seizure duration in the face mask group was significantly shorter than that in the laryngeal mask group (33 +/- 11 seconds, 42 +/- 10 seconds, respectively p<0.01). The change in PaCO2 was minor in the laryngeal mask group compared with the face mask group and seizure duration was longer in the laryngeal mask group. Laryngeal mask may be suitable for airway management during ECT anesthesia, especially when fitting a face mask is difficult.