Effect of artificial airway on ear complications from hyperbaric oxygen

Etiology, Diagnosis, Complications, and Management of Acute Otitis Media in Children

Acute otitis media (AOM) is the most common infectious disease encountered by children under the age of two years and the most common cause of antibiotic use in children in the United States. AOM causes irritability, sleeplessness, decreased appetite, imbalance, and dizziness in patients, especially young children. This assessment was conducted to measure the effectiveness of surgical interventions in treating AOM. We reviewed the present findings regarding the etiology, clinical presentations, diagnosis, treatment, and surgical treatment of complications of AOM. Pain associated with AOM (otalgia) can be severe enough to cause parents to seek treatment for their infants or children. Various suggested measures have been used to treat AOM; antibiotic treatment with amoxicillin is still the treatment of choice for AOM, yet other antibiotics may be used in cases of allergy to penicillin or recent use of amoxicillin. Surgical intervention has been introduced and studied as a diagnostic, therapeutic, and preventive measure for AOM; nevertheless, a few studies have shown that surgical interventions are beneficial in treating and preventing AOM compared to the common practice of using antibiotics. Overdiagnosis of AOM is widespread, leading to injudicious antibiotic use, which contributes to antibiotic resistance. Further management should be determined together with the parent, particularly if observation is the primary intervention.

Effect of antiplatelet and/or anticoagulation medication on the risk of tympanic barotrauma in hyperbaric oxygen treatment patients, and development of a predictive model

INTRODUCTION

Middle ear barotrauma (MEBt) is a common side effect of hyperbaric oxygen treatment (HBOT) and can result in pain, hearing loss, tinnitus and otorrhagia. The use of antiplatelet/anticoagulant drugs is thought to increase the risk and severity of MEBt during HBOT.

METHODS

Single centre, retrospective observational cohort study of all patients treated with HBOT over a 4-year period (between 01 January 2015 to 31 December 2018) looking at the incidence of MEBt and the concurrent use of antiplatelet and/or anticoagulant drugs. MEBt was assessed by direct otoscopy of the tympanic membrane post-HBOT and scored using the modified Teed classification. Multivariate modelling assessed the relationship between antiplatelet and/or anticoagulation drug use, age, sex, and MEBt during HBOT.

RESULTS

There was no evidence that antiplatelet and/or anticoagulation drugs increase the risk of tympanic barotrauma in HBOT patients. The prevalence of MEBt was higher in female patients than in males (χ2 P = 0.004), and increased with age (χ2 P = 0.048). No MEBt was recorded in patients undergoing recompression therapy for decompression sickness or cerebral arterial gas embolism.

CONCLUSIONS

In this retrospective single-centre study, antiplatelet and/or anticoagulation drugs did not affect the risk of MEBt, but both age and sex did, with greater prevalence of MEBt among older patients and females compared with younger patients and males. A predictive model, requiring further validation, may be helpful in assessing the likelihood of MEBt in patients undergoing HBOT.

Hyperbaric Oxygen Therapy: Side Effects Defined and Quantified

Significance: Hyperbaric oxygen therapy (HBOT) is an important advanced therapy in the treatment of problem wounds, including diabetic foot ulcers and late effect radiation injury. HBOT remains among the safest therapies used today. Nonetheless, there are side effects associated with HBOT. It is important for providers to be able to identify, understand, and quantify these side effects for prevention, management, and informed consent. Recent Advances: The past two decades have seen significant advancements in our understanding of the underlying mechanisms of HBOT. This has led to a better understanding of the underlying reason for clinical benefit. It has also led to a better understanding of its side effects. Moreover, more recent literature allows for better quantification of these side effects. This review will highlight these side effects. Critical Issues: Wound healing in the case of problem nonhealing wounds requires the use of various advanced treatment modalities, including HBOT. HBOT has been shown to significantly improve healing rates in certain problem wounds, including advanced diabetic foot ulcers and late effect radiation injury. It is provided in a variety of clinical settings by providers with varying levels of expertise. It is important for those providing this therapy to understand the potential side effects. Future Directions: Research in HBOT has led to significant advancements in the area of wound healing. At the same time, there remains a variety of treatment protocols used at different institutions. It is important to quantify risk and benefit at different treatment pressures and times to better standardize treatment and improve patient care.

Otological complications associated with hyperbaric oxygen therapy

The objective of the present study was to clarify the features of otological complications for hyperbaric oxygen therapy (HBOT) and the risk factors for these complications. We enrolled 1115 patients (776 males and 339 females; age 5-89 years) who underwent HBOT. All otological symptoms experienced during HBOT sessions were evaluated, and risk factors were analysed using multivariate logistic regression analysis. Otoscopic findings and interventions for otological complications were assessed in 58 symptomatic patients who visited the Otolaryngology Department. Otological symptoms were experienced by 165 (14.8 %) of the 1115 patients. The multivariate logistic regression analysis identified ages of >60 years and female sex as independent risk factors, whereas patients with sports injuries were at lower risk than those with other primary diseases, except for severe infectious disease. Eighty-two patients (49.7 %) suffered from symptoms at the first HBOT session. The most prevalent symptoms were otalgia (157/165), followed by ear fullness (13/165), hearing loss (12/165) and tinnitus (3/165). One patient experienced vertigo and deterioration of the bone-conduction pure-tone thresholds, suggesting inner ear barotrauma. In 116 ears of the 58 symptomatic patients, abnormal otoscopic findings were recognized in 58 ears (50.0 %). Twenty-seven of the 58 ears required myringotomy or tube insertion, and HBOT was stopped in eight ears in four patients. Of the remaining 58 ears with normal otoscopic findings, 51 received no treatment. Physicians should be aware of both middle and inner ear barotrauma as potential complications of HBOT.

Different reactions of human nasal and Eustachian tube mucosa after hyperbaric oxygen exposure: a pilot study

Impairment of Eustachian tube function has been observed after hyperbaric oxygen treatment as well as after diving on oxygen used as breathing gas. The aim of the present study was to evaluate the influence of hyperbaric oxygen exposure on Eustachian tube ventilatory function and airflow characteristics of the nose. Six police task force divers performing two consecutive dives within a regular training schedule on oxygen were examined. Middle ear impedance, and nasal airflow velocities before and after diving as well as on the morning after the dive day were measured. Middle ear impedance decreased overnight in comparison to pre-dive values (P = 0.027) as well as compared to the value after the first dive (P = 0.032). Rhinoflowmetry did not reveal any changes of nasal airflow velocities related to the dives. Furthermore, no association between middle ear impedance and nasal airflow velocities was found. An impairment of Eustachian tube ventilatory function was obtained after hyperbaric oxygen exposure during dives employing oxygen as breathing gas. This impairment, however, was not associated with altered airflow characteristics of divers' noses. Thus, it seems unlikely that hyperbaric oxygen exerts an effect on the nasal mucosa similar to that on the Eustachian tube mucosa.

Hyperbaric oxygen in the critically ill

OBJECTIVE

To review aspects of hyperbaric medicine pertinent to treating critically ill patients with hyperbaric oxygen in both monoplace and multiplace chambers.

DATA SOURCES

Literature review of online databases, research repositories, and clinical trial registries.

RESULTS

The search of these resources produced information regarding technical considerations, feasibility, risk, and patient management. Hyperbaric oxygen is used in treating a number of disorders that occur in critically ill patients, including acute carbon monoxide poisoning, arterial gas embolism, severe decompression sickness, clostridial gas gangrene, necrotizing fasciitis, and acute crush injury. Most chambers in the United States treat outpatients with problem nonhealing wounds, and many chambers are not hospital-based. Only a few hyperbaric medicine centers have intensive care unit-level staffing, specialized equipment, a 24/7 schedule, and experience in treating critically ill patients. Not all intensive care unit-related equipment can be subjected to hyperbaric pressurization, and some equipment may increase the risk for fire inside the chamber.

CONCLUSIONS

Treating critically ill patients with hyperbaric oxygen requires specialized equipment and personnel with intensive care unit skills and knowledge of the physiology and risks unique to hyperbaric oxygen exposure. Like with all medical interventions, it is important to consider the risk vs. the benefit of hyperbaric oxygen for any given critical care disorder, but hyperbaric oxygen can be delivered safely to critically ill patients. Many critical care environments without present hyperbaric oxygen capability may wish to consider offering hyperbaric oxygen to patients with hyperbaric oxygen-approved indications.

Middle Ear Barotrauma with Hyperbaric Oxygen Therapy: Incidence and the Predictive Value of the Nine-step Inflation/Deflation Test and Otoscopy

We conducted a prospective study to determine the incidence of middle ear barotrauma in patients who were undergoing hyperbaric oxygen therapy (HBOT). We also investigated the value of the nine-step inflation/deflation test and otoscopic findings before and immediately after the initial HBOT session in predicting barotrauma in an attempt to establish some criteria for prophylaxis. The study was conducted on 36 ears of 18 adults who had no history of eustachian tube dysfunction. Patients were being treated with HBOT for sudden hearingloss, wound-healing complications, or complications of diabetes. After 7 days of HBOT, barotrauma was seen in 12 of the 18 patients (66.7%) and in 18 of the 36 ears (50.0%). The nine-step inflation/deflation tests, which were performed before and immediately after the initial HBOT session, were not predictive of barotrauma (p = 0.095 before and p = 0.099 after). However, otoscopic findings obtained immediately after the first session of HBOT were predictive of barotrauma, with a sensitivity and specificity of 83 and 100%, respectively. We conclude that patients with even minor positive pathologic findings on otoscopy immediately following HBOT are at increased risk of middle ear barotrauma if HBOT is to be continued without prophylaxis.

[Hyperbaric oxygenation: characteristics of intensive care and emergency therapy]

Hyperbaric oxygenation (HBO) is a decisive component of a comprehensive interdisciplinary intensive care therapy for numerous disorders, such as gas embolism, severe decompression illness or carbon monoxide (CO) intoxication. However, barochambers with 24 h accessibility are often not readily available, thus, requiring an interhospital transport of critically ill patients. In order to minimise additional risks, a skilled transportation team should be involved. Furthermore, the specific physical and physiological features of HBO require that the transportation personnel must be trained adequately. Specific characteristics of the interhospital transfer of HBO patients are described as well as adverse effects and their specific therapy.

Evaluation and management of decompression illness--an intensivist's perspective

Decompression illness (DCI) is becoming more prevalent as more people engage in activities involving extreme pressure environments such as recreational scuba-diving. Rapid diagnosis and treatment offer these patients the best chance of survival with minimal sequelae. It is thus important that critical care physicians are able to evaluate and diagnose the signs and symptoms of DCI. The cornerstones of current treatment include the administration of hyperbaric oxygen and adjunctive therapies such as hydration and medications. However, managing patients in a hyperbaric environment does present additional challenges with respect to the particular demands of critical care medicine in an altered pressure environment. This article reviews the underlying pathophysiology, clinical presentation and therapeutic options available to treat DCI, from the intensivist's perspective.

Can Eustachian Tube Ventilatory Function Impairment After Oxygen Diving Be Influenced by Application of Free Radical Scavenger Vitamins C and E?

OBJECTIVES/HYPOTHESIS

To evaluate the influence of free radical scavenger vitamins C and E on eustachian tube ventilatory function changes related to oxygen dives.

STUDY DESIGN

Prospective, randomized, double-blind, placebo-controlled study of middle ear impedance changes of oxygen divers being orally treated with free radical scavenger vitamins C and E.

METHODS

Fifteen divers were allocated to two groups. Before diving on oxygen on consecutive days (days 1 and 2), divers in group 1 took a daily dose of 1 g ascorbic acid and 600 International Units d-alpha-tocopherol and divers in group 2 were given placebo. Before diving and 2 and 24 hours after diving on days 1 and 2, middle ear impedance was measured.

RESULTS

Impedance decreased overnight after dive 1 (P =.04) but not after dive 2 (P =.31). No impedance differences were found between groups after the dive on day 1 (P =.83). Twenty-four hours after the dive on day 1 and after the dive on day 2, impedance values in both groups were different (P =.02 vs. P =.07), emphasizing slightly more negative pressures in the vitamin group.

CONCLUSION

Vitamins C and E did not reduce eustachian tube ventilatory function impairment overnight after the dive on day 1, suggesting no evidence of free radical-mediated toxicity affecting the eustachian tube or middle ear mucosa. Repetitive oxygen dives may cause tissue adaptation suggesting other than antioxidant defense mechanisms.

Inner ear barotrauma after stapedectomy in the guinea pig

OBJECTIVE

The safety of scuba diving after stapedectomy is controversial. Stapedectomy is thought to predispose to inner ear barotrauma (e.g., perilymph fistula); however, many individuals continue to scuba dive following stapedectomy without ill effects. The purpose of this study was to evaluate the cochlear effects of barotrauma, similar to that experienced with scuba diving, on inner ears previously treated with stapedectomy.

STUDY DESIGN

Prospective, controlled.

METHODS

Sixteen Hartley albino guinea pigs underwent unilateral total stapedectomy followed by hyperbaric dives on 5 consecutive days, beginning 3 weeks after stapedectomy. Cochlear effects were determined using click and tone-pip evoked electrocochleographic thresholds and cochlear hair cell counts.

RESULTS

Mean auditory thresholds increased by 29 dB after stapedectomy (P < .001), then remained stable thereafter. Mean thresholds in both the operated and control ears did not change with hyperbaric dives. Evidence of middle ear barotrauma (e.g., hemorrhage or tympanic membrane perforation) was observed in eight poststapedectomy ears and five control ears, but none demonstrated significant threshold elevation greater than or equal to 10 dB. Hair cell counts were not different between operated and control ears.

CONCLUSIONS

Stapedectomy does not appear to predispose to cochlear sequelae in the guinea pig model of diving-related barotrauma.

Tympanostomy tubes: types, indications, techniques, and complications

This article reviews current concepts and applications involving tympanostomy tubes. The various types of tympanostomy tubes, indications, complications, and techniques are discussed. Applications ranging from otitis media to dysfunction of the eustachian tube associated with nasopharyngeal carcinoma are included. Experience drawn from patient care and currently published studies support the conclusions made in this article.

Hearing loss in critical care: an unappreciated phenomenon

OBJECTIVES

The objectives of this article are to review the physiology of hearing; identify acute pathologic and perceived causes of hearing loss in the adult critically ill patient; and to discuss its evaluation, treatment, and prevention.

DATA SOURCES

Computerized bibliographic search of MEDLINE from 1966 to the present of all relevant articles in all languages on acute hearing loss in the adult population.

DATA EXTRACTION

Data gathered from studies and reports of acute hearing loss as relates or potentially relates to the peri-intensive care unit (ICU) period.

DATA SYNTHESIS

Hearing loss is an infrequent but potentially serious complication associated with critical illness. The causes of hearing loss in the ICU patient include mechanical or accidental trauma, administration of ototoxic medications, local or systemic infections, vascular and hematologic disorders, autoimmune diseases, and environmental noise. Patients who are elderly, have coexisting liver or renal failure, or who are receiving concomitantly administered ototoxic drugs are particularly at risk for developing hearing loss. A thorough assessment of potential causes of hearing loss and audiological examination should be undertaken on all ICU patients suspected of hearing loss. Mechanical, pharmacologic, and environmental strategies are available to decrease the incidence of hearing loss in this patient population.

CONCLUSIONS

Hearing loss should be recognized as a potential clinical problem by intensivists. Its causes should be identified and appropriate evaluation and therapy initiated. High risk populations should be identified for preventive measures.

Inner and middle ear hyperbaric oxygen-induced barotrauma

Patients receiving hyperbaric oxygen (HBO) therapy can sustain inner and middle ear barotrauma. The purpose of this study is to define the incidence and significance of HBO-related barotrauma, in addition to establishing guidelines for prophylactic myringotomy or tympanostomy tube placement. Thirty patients were stratified into two groups (those able to autoinflate and those unable to autoinflate the middle ear) and barotrauma was assessed by otoscopy, tympanometry, high-frequency audiometry, and distortion product otoacoustic emission (DPOAE) testing. Ten of 11 patients (91%) from the noninflater group suffered middle ear barotrauma, and seven of 19 patients (37%) from the autoinflater group sustained middle ear barotrauma. Patients unable to autoinflate the middle ear were shown to have a higher incidence and greater severity of barotrauma than patients able to autoinflate. Pretreatment pressure-equalizing tubes or myringotomies should be considered for patients undergoing HBO therapy who have an artificial airway or have eustachian tube dysfunction and have failed conservative medical intervention. A significant change in DPOAEs (loss of emissions over a 1-kHz range) was found in four of 15 autoinflaters (27%) and two of seven noninflaters (29%). There was no significant difference between the groups. The decrease in DPOAEs was not associated with a change in conventional audiometry.

Prophylaxis against middle ear barotrauma in US hyperbaric oxygen therapy centers

The most common complication of hyperbaric oxygen (HBO) treatment is middle ear barotrauma, which can lead to permanent hearing loss and vertigo. Unconscious patients and infants present a special diagnostic challenge because of difficulties in communicating pain and equalizing pressure across the ears. This study involved a phone survey to all hospital-based HBO centers in the United States concerning routine practice for middle ear barotrauma prophylaxis. Results indicate that more than a fifth of centers always do routine prophylactic myringotomies on intubated patients (30 of 126) and infants (19 of 86). Less than half of centers never performed the procedure as routine prophylaxis. A third of centers (49 of 145) routinely administered prophylactic drugs before HBO treatment. Topical nasal decongestants, particularly oxymetazoline, were preferred to systemic oral medications (chi2 = 20.8, P<.001). These results show that there is great variance in clinical practice with regard to middle ear barotrauma prophylaxis among US HB0 centers. Many centers are using unproven therapies such as topical nasal decongestants.