The effect of combined spinal-epidural (CSE) anaesthesia and size of spinal needle on postoperative hearing loss after elective caesarean section

Combined spinal-epidural vs. spinal anaesthesia for caesarean section: meta-analysis and trial-sequential analysis

Combined spinal-epidural and single-shot spinal anaesthesia are both used for caesarean section. It has been claimed in individual trials that combined spinal-epidural is associated with higher sensory spread and greater cardiovascular stability. We set out to gather all available evidence. We performed: a systematic literature search to identify randomised controlled trials comparing combined spinal-epidural with spinal anaesthesia for caesarean section: conventional meta-analysis; trial-sequential analysis; and assessment of trial quality using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Fifteen trials with high heterogeneity, including 1015 patients, were analysed. There was no significant difference between combined spinal-epidural and spinal anaesthesia for our primary outcomes maximum sensory height and vasopressor use (mg ephedrine equivalents). However, trial-sequential analysis suggested insufficient data and the GRADE scores showed 'very low' quality of evidence for these outcomes. The secondary outcomes hypotension, time for sensory block to recede to the level of T10, and the combined outcome of nausea and vomiting, did not differ significantly between the interventions. The block times were statistically significantly longer for combined spinal-epidural in individual trials, but only one trial showed a clinically meaningful difference (11 min). Based on this analysis, and taking into consideration all comparisons irrespective of whether drugs had been applied via the epidural route, there is not enough evidence to postulate any advantage compared with the spinal technique. Future analyses and studies need to examine the potential advantages of the combined spinal-epidural technique by using the epidural route intra- and/or postoperatively.

The effects of spinal anesthesia on auditory function in pediatric patients

OBJECTIVES

Persistent or transient hearing loss (HL) is a less-recognized complication of spinal anesthesia (SA) in the pediatric population, although it has been previously reported in adults. The primary aim of this study was to investigate the effects of SA on auditory function in the pediatric population.

METHODS

After gaining institutional approval and parental consent, 30 American Society of Anesthesiologists physical status I-II children between 4 and 15 years undergoing lower extremity orthopedic surgery were enrolled in this prospective study. Spinal blocks were performed in the midline with a 25G Quincke needle using 0.5% hyperbaric bupivacaine. Transient evoked otoacoustic emission (TEOAE) and distortion product otoacoustic emission (DPOAE) tests were administered before surgery and one-day postoperative. Children with detected HL were retested on postoperative day seven. Preoperative and postoperative results were compared. A Wilcoxin Signed-Ranks test (with Bonferroni correction) was used for statistical analyses.

RESULTS

There was no statistically significant HL in the postoperative period compared to the preoperative period. In 29 of 30 patients, no difference was detected at any frequency tested. In one patient, TEOAE and DPOAE tests were found to be decreased on postoperative day one. In this patient, control tests were found to be improved on postoperative day seven.

CONCLUSIONS

Administration of SA may results in a low probability of transient hearing loss with no clinical significance in children 4-15 years of age.

Sudden Sensorineural Hearing Loss after Orthopedic Surgery under Combined Spinal and Epidural Anesthesia

Postoperative hearing loss following nonotologic surgery is rare. For patients undergoing subarachnoid anesthesia, the loss of cerebral spinal fluid and hence the drop in intracranial pressure can result in hearing loss and cranial nerve palsy. We report a case in which a patient sustained orthopedic surgery under combined spinal and epidural anesthesia complicated by severe and persistent sensorineural hearing loss. This report is a reminder that postoperative sudden sensorineural hearing loss is a poorly understood complication. A high index of suspicion is required for early diagnosis of this complication, although prompt treatment does not guarantee a good outcome.

Assessment of Hearing Loss by OAE in Asphyxiated Newborns

BACKGROUND

Severe birth asphyxia (apgar < 7 at the 5th minute of birth) is recognized as a hearing loss risk factor by the joint committee on infant hearing (JCIH). About half of the newborns with hearing loss do not indicate any sign and risk factor at birth. Accordingly, the joint committee recommended performance of hearing screening test in 2000, especially for babies born with risk factors.

OBJECTIVES

The aim of this study was to evaluate hearing loss in asphyxiated neonates. Early diagnosis would result in early treatment of these newborns.

PATIENTS AND METHODS

We assessed the relationship between asphyxia and hearing impairment in newborns admitted to a referral hospital, Tehran, Iran within 3 years (2003 - 2006). Hearing problems were diagnosed and followed by otoacoustic emission (OAE) in the third and fifth days of birth. Asphyxiated neonates with abnormal OAE were referred to an ENT specialist; second OAE and tympanometry were carried out after 2 weeks. Based on the results, newborns underwent treatment or were discharged.

RESULTS

Of 149 asphyxiated neonates, 80 had mean first minute apgar score of 4.01, and mean 5th minute score was 7.24. Two percent (3/149) of asphyxiated neonates had abnormal OAEs. No statistical correlation was found between the 5th minute apgar score and abnormal OAE (P value = 0.391). However, a significant relationship between the mean birth weight and abnormal OAE (P value = 0.0406) was found.

CONCLUSIONS

It seems that birth asphyxia is not correlated with hearing loss.

Role of repeated epidural injections in preventing post-spinal hearing loss

STUDY OBJECTIVE

To determine if epidural volume extension and continued postoperative epidural injections prevent hearing loss associated with a 23-gauge (G) Quincke spinal needle.

DESIGN

Prospective, double blinded trial.

SETTING

Operating rooms.

PATIENTS

30 adult patients scheduled for lower abdominal or perineal surgery during spinal anesthesia.

INTERVENTIONS

Patients were divided into two groups of 15 each. All patients received subarachnoid injection with a 23-G Quincke needle. While patients in Group S received a single-shot spinal, Group E patients underwent epidural catheter placement one intervertebral space above. The epidural catheter was bolused with 10 mL of normal saline followed by postoperative epidural boluses of local anesthetic for analgesia as needed.

MEASUREMENTS

Patients' auditory function was evaluated by pure tone audiometry (frequencies of 250-8,000 Hz) on the day before and two days after receiving the spinal anesthesia.

MAIN RESULTS

Unilateral low-frequency hearing loss (500 Hz) was seen in Group S (P < 0.05). It was prevented by the repeated epidural injections as used in Group E.

CONCLUSION

Following spinal anesthesia, epidural volume extension with 10 mL of normal saline followed by epidural local anesthetic boluses titrated to adequate postoperative analgesia (6-8 mL each time) prevents post-spinal hearing loss.

Cauda Equina Syndrome and Profound Hearing Loss After Spinal Anesthesia with Isobaric Bupivacaine

A 33-yr-old man undergoing anorectal surgery developed cauda equina syndrome and bilateral profound hearing loss after single-injection spinal anesthesia with isobaric bupivacaine. There was no pain on needle placement. Neurologic assessment found impaired sensation to pinprick in the perineal region, lower extremity paralysis, and bowel and bladder incontinence. In addition, he developed a bilateral profound hearing loss involving the low frequencies, with the left side more affected than the right side. Although hearing impairment can occur with cerebrospinal fluid leakage, the etiology of cauda equina syndrome is uncertain. The simultaneous occurrence of these events has not been previously reported.

Evaluation of Hearing Loss after Spinal Anesthesia with Otoacoustic Emissions

The aim of this study was to determine the degree and reversibility of hearing loss (HL) following spinal anesthesia with an objective audiometric test: otoacoustic emissions (OAE). Eleven patients (22 ears) who were undergoing surgery under spinal anesthesia were included in this study. Transient-evoked otoacoustic emissions (TEOAE) and distortion product otoacoustic emissions (DPOAE) were evaluated 1 day before the operation and postoperative day 1, 2, and 15. DPOAE were recorded as DPgram and input/output functions (I/O). The emission amplitudes of the TEOAE and DPOAE of right and left ears were found to be affected immediately after the surgery and progressive improvement detected with full recovery within postoperative 15 days. These changes were mainly at around 1,500-3,000 Hz. None of the patients had permanent OAE amplitude deterioration. Transient HL may occur more often than it is generally assumed, and the symptoms might not be recognized. OAE is an effective and objective way of evaluating the HL in this particular group of patients. We suggest informing patients about this transient HL for medicolegal issues.

Jugular Compression and Radionuclide Cisternographic Patterns in Patients With Chronic Headache

OBJECTIVE

We investigated the value of the jugular compression test (JCT) in screening patients with chronic headache attributable to persistent cerebrospinal fluid (CSF) leakage.

METHODS

Clinical records of 35 consecutive patients who underwent both 111In-diethylenetriamine pentaacetic acid radioisotope (RI) cisternography and JCT were retrospectively analyzed.

RESULTS

A strong correlation was seen between JCT and RI cisternographic findings. Most patients who reported a feeling of fullness in the ear, hearing loss or headache during JCT had positive findings on RI cisternograms indicative of CSF leakage. In contrast, no RI study abnormalities were seen in patients reporting no symptoms in JCT.

CONCLUSIONS

Among patients complaining of refractory headache and other miscellaneous symptoms, JCT may represent a simple, economic, and reliable technique in the screening of candidates for RI cisternography to evaluate CSF leakage. A subgroup of patients with chronic headache may have persistent CSF leakage.