Intractable Hiccups

Refractory singultus and area postrema syndrome as a presentation of neurocysticercosis

Neurocysticercosis (NCC) is the most common parasitic infection of the central nervous system, caused by the pork tapeworm, Taenia solium Common presenting features are seizures, headaches and focal neurodeficits. The present report details the anecdote of a middle-aged Asian man, who presented with subacute onset of persistent nausea, vomiting and hiccups. Following unsuccessful trials with numerous prokinetic, antipsychotic, muscle relaxant and anticonvulsant medications, as well as an uneventful battery of gastrointestinal tests, he was referred for neurological evaluation. The constellation of symptoms was congruent with the diagnosis of area postrema syndrome. Although initial CT scan of brain was normal, MRI with contrast evaluation revealed a circumscribed, ring-enhancing lesion of the dorsal medulla oblongata, reminiscent of colloid vesicular stage of NCC. The patient was successfully treated with steroids and albendazole. The association of refractory singultus, nausea and vomiting and NCC is thus far, not reported in the literature.

The annoyance of singultus: a case report of a rare adverse effect after epidural steroid injection

OBJECTIVE

Cervical epidural steroid injections (ESIs) can provide effective pain management for patients suffering from chronic neck pain due to various pathological changes of the cervical spine. There are several rare adverse effects reported from interventional pain procedures, including persistent hiccups ("singultus"). Based on a limited number of cases, we propose a modified treatment algorithm for this adverse outcome (Fig. 3).

CASE REPORT

Singultus has been documented as an adverse effect of interventional pain procedures, including epidural steroid, facet joint, and sacroiliac joint injections. We describe the case of a general contractor who presented to our clinic with chronic neck pain and central canal stenosis. The patient received an uncomplicated lumbar ESI in the past and was recommended for a cervical interlaminar ESI. After an uneventful C6-C7 interlaminar ESI with dexamethasone, 1% lidocaine, and normal saline the patient developed singultus. Baclofen was sent to his pharmacy, but this was unsuccessful at alleviating his hiccups. The patient was subsequently started on chlorpromazine and found relief from his symptomatology.

CONCLUSION

Persistent hiccups after ESI or interventional pain procedures can be treated with conservative measures and non-pharmacologic methods, with escalation to therapy with baclofen, gabapentin, pregabalin, metoclopramide, chlorpromazine, other antipsychotic or antidopaminergic agents, and possible dual or triple therapy if further indicated.

Peripheral nerve stimulation (PNS) of the phrenic nerve for intractable hiccups: a novel use case report

BACKGROUND

Intractable hiccups, defined as those persisting for over 1 month, represent a rare but significant clinical challenge often associated with substantial morbidity and refractory to standard treatments.

CASE PRESENTATION

This case report describes the innovative use of phrenic nerve peripheral neuromodulation for managing chronic intractable hiccups in a 73-year-old male patient with a 6-year history of daily hiccups. Conventional treatments and interventional procedures had failed to provide lasting relief. Bilateral phrenic nerve peripheral nerve stimulation (PNS) placed under ultrasound guidance resulted in immediate and substantial improvement, with the patient's Hiccup Assessment Instrument score decreasing from 6/10 to 2/10. The patient experienced significant enhancements in speech and quality of life without complications.

CONCLUSIONS

This novel application of phrenic nerve PNS highlights its potential as a therapeutic strategy for intractable hiccups, underscoring their pathophysiologic involvement of the diaphragm and respiratory muscles. The findings suggest that phrenic nerve PNS could offer a viable treatment option for patients unresponsive to conventional therapies, warranting further research to establish its long-term efficacy and safety.

Intractable Hiccups in a Patient With End-Stage Renal Disease: A Five-Month Ordeal Resolved Through Hemodialysis

Hiccups, a common and usually self-limiting condition, are caused by involuntary, spasmodic contractions of the diaphragm and intercostal muscles, followed by the sudden closure of the glottis. While most cases resolve spontaneously, persistent hiccups (lasting 48 hours to one month) and intractable hiccups (lasting more than one month) require medical attention. Intractable hiccups, although rare, can significantly impair a patient's quality of life. The etiology of intractable hiccups is diverse, but they are often associated with serious underlying medical conditions, such as severe renal dysfunction and uremia. We present the case of a 72-year-old male patient with stage IV chronic kidney disease (CKD) who developed intractable, violent hiccups following a mild COVID-19 infection. Despite treatment attempts with chlorpromazine and baclofen, the hiccups persisted for five months and only resolved after the initiation of hemodialysis. Interestingly, the patient's renal function deteriorated significantly during the period of hiccup persistence, suggesting a possible link between the hiccups and the progression of CKD, likely exacerbated by COVID-19. This case highlights the challenges of managing intractable hiccups in patients with advanced CKD and emphasizes the importance of addressing underlying metabolic derangements in such complex clinical scenarios. Moreover, it contributes to the growing evidence supporting the role of dialysis in resolving intractable hiccups associated with severe renal dysfunction.

Hiccup Relief Using Active Prolonged Inspiration

Background Hiccups are a common physiologic reflex resulting from intermittent and involuntary spasmodic contraction of the diaphragm and intercostal muscles. While most cases are self-limited, lasting less than 48 hours, rare pathologies may result in prolonged symptoms. Hiccups can be disruptive and uncomfortable, leading many to seek management strategies using common home remedies. Few methods for terminating hiccups have been published in the scientific literature. We report the efficacy of the Hiccup relief using Active Prolonged Inspiration (HAPI) technique, which combines phrenic and vagal nerve stimulation with transient hypercapnia for hiccup relief. Methods Twenty patients with self-limited hiccups and one patient with prolonged hiccups were successful in eliminating hiccups using HAPI. In this method, patients are instructed to inspire maximally. Once at the peak of inspiration, they continue to attempt to inspire with an open glottis for a total of 30 seconds. This is followed by a slow expiration and resumption of normal respiration. Results In all cases, patients reported immediate hiccup relief. Conclusion These findings suggest the HAPI technique is a simple and viable method for hiccup relief. Further studies are needed to validate effectiveness.

Acupuncture in the treatment of post-stroke hiccup: A systematic Review and meta-analysis

Aim: Central hiccups following a stroke are a frequent complication, exerting adverse effects on both the stroke condition and the patient's daily life. Existing treatments exhibit limited efficacy and pronounced side effects. Acupuncture has been explored as a supplementary intervention in clinical practice. This study aims to investigate the clinical effectiveness of acupuncture for post-stroke hiccups.Methods: To identify published clinical randomized controlled trials addressing post-stroke hiccups treatment, comprehensive searches were conducted across PubMed, the Cochrane Library, EMBASE, Web of Science, Chinese Biological Medical (CBM), Wanfang Database, and China Science and Technology Journal (VIP). In addition, we scrutinized ClinicalTrials.gov and the Chinese Clinical Trial Registry. Employing Cochrane Handbook 5.1.0 and Review Manager 5.4 software, three authors independently reviewed literature, extracted data, and evaluated study quality. Data analysis was performed using Stata 16.0 and Review Manager 5.4.Results: A total of 18 trials were encompassed in the analysis. In comparison to standard treatment, acupuncture exhibited a significant enhancement in treatment effectiveness (RR: 1.27, 95% CI: 1.21-1.33; P < 0.00001). Notably, Hiccup Symptom Score displayed a considerable decrease (WMD: -1.28, 95% CI: -1.64 to -0.93; P < 0.00001), concurrent with a noteworthy improvement in the quality of life (WMD: 8.470, 95% CI: 7.323-9.617; P < 0.00001). Additionally, the incidence of adverse reactions decreased (RR: 0.45, 95% CI: 0.16-1.25; P = 0.13), and there was a significant reduction in SAS (WMD: -7.23, 95% CI: -8.47 - -5.99; P < 0.00001).Conclusions: Our investigation suggests that acupuncture could prove effective in post-stroke hiccup treatment. Nonetheless, due to concerns about the quality and size of the included studies, conducting higher-quality randomized controlled trials to validate their efficacy is imperative.

Phrenic nerve block combined with stellate ganglion block for postoperative intractable hiccups: a case report

Postoperative intractable hiccups slow patient recovery and generate multiple adverse effects, highlighting the importance of investigating the pathogenesis and terminating the hiccups in a timely manner. At present, medical and physical therapies account for the main treatments. We encountered a case in which postoperative intractable hiccups after biliary T-tube drainage removal ceased with the application of an ultrasound-guided block of the unilateral phrenic nerve and stellate ganglion. No complications developed, and the therapeutic effect was remarkable. To our knowledge, this approach has not been reported to date. Simultaneously blocking the phrenic nerve and stellate ganglion may be a treatment option for intractable hiccups.

Persistent Post-endoscopic Retrograde Cholangiopancreatography Hiccups: An Unusual Presentation of Bile Reflux

Bile reflux is a pathological retrograde flow of bile into the stomach that may lead to gastric overdistension and gastritis. It generally manifests as abdominal pain, nausea, vomiting, or heartburn. Hiccups have thus far not been described as part of its presentation. Here, we describe a case of excessive post-endoscopic retrograde cholangiopancreatography bile accumulation in the stomach that caused persistent hiccups requiring endoscopic suctioning.

Fatal posterior circulation stroke with persistent hiccups, sinus arrest and post-hiccup syncope: A case report

RATIONALE

Diagnosis of posterior circulation stoke is difficult, and magnetic resonance imaging especially diffusion-weighted imaging is superior to computed tomography. Persistent hiccups, sinus arrest, and post-hiccup syncope are extremely rare symptoms of posterior circulation stroke. However, there is no effective treatment for persistent hiccup.

PATIENT CONCERN AND DIAGNOSIS

We describe a case of a 58-year-old hypertensive woman diagnosed with acute posterior circulation stroke who presented with persistent hiccups, sinus arrest, and post-hiccup syncope. Diffusion-weighted imaging revealed a high-intensity signal involving the left middle cerebellar peduncle and several spotted areas in the right occipital lobe.

INTERVENTIONS

Permanent pacemaker was implanted and metoclopramide was used to treat persistent hiccups.

OUTCOME

The patient developed aspiration pneumonia and morbid dysphoria, and eventually died.

LESSONS

Posterior circulation stroke can cause cardiovascular and respiratory dysfunction. Consequently, physicians should pay more attention to posterior circulation lesions in patients with arrhythmia and syncope. An effective method to treat persistent hiccups is urgently needed.

Cervical repetitive peripheral magnetic stimulation relieves idiopathic persistent hiccups: A preliminary study of case report

OBJECTIVE

We postulated that repetitive peripheral magnetic stimulation (rPMS) might treat idiopathic persistent hiccups. This study aimed to determine the clinical effect of rPMS on hiccup alleviation.

METHODS

Seven patients with idiopathic persistent hiccups experienced the cervical rPMS session (1 Hz, 656 stimuli) in this prospective clinical series from November 2018 to May 2021. The rPMS session was applied once daily until the hiccups were utterly relieved. During the treatment, the round coil was transversally positioned over the upper nape area, and the center of the coil was placed at the level of the C4 vertebrae. The subjective assessment scale (SAS) scores and the hiccup frequency were assessed before and after rPMS treatment.

RESULTS

A total of 7 patients were enrolled. All were male post-stroke patients ([mean ± SD] age, 58.5 ± 9.85 years) with dysphasia, 3 patients (3/7) were fed with a nasogastric tube, and 4 patients (4/7) were with dysarthria. The mean duration of hiccups was 4.14 ± 3.63 days (range 2-12 days). The rPMS therapy eliminated hiccups in all 7 patients. The mean sessions which stopped hiccupping were 3.43 ± 2.57 (range 1-9). The mean value of the SAS scores before rPMS therapy was 7 ± 1 (range 6-8), and it was decreased to zero after the therapy (0). No recurrence of hiccups was observed within 2 weeks of the last rPMS session. rPMS therapies were not associated with severe adverse effects.

CONCLUSION

The cervical rPMS therapy is beneficial in treating idiopathic persistent hiccups, particularly in post-stroke patients.

Risk Factors for Hiccups after Deep Brain Stimulation of Subthalamic Nucleus for Parkinson's Disease

Background: After deep brain stimulation (DBS), hiccups as a complication may lead to extreme fatigue, sleep deprivation, or affected prognosis. Currently, the causes and risk factors of postoperative hiccups are unclear. In this study, we investigated the risk factors for hiccups after DBS of the subthalamic nucleus (STN) for Parkinson’s disease (PD) under general anesthesia. Methods: We retrospectively included patients who underwent STN DBS in the study, and collected data of demographic characteristics, clinical evaluations, and medications. According to the occurrence of hiccups within seven days after operation, the patients were divided into a hiccups group and non-hiccups group. The potentially involved risk factors for postoperative hiccups were statistically analyzed by logistic regression analysis. Results: A total of 191 patients were included in the study, of which 34 (17.80%) had postoperative transient persistent hiccups. Binary univariate logistic regression analysis showed that male, higher body mass index (BMI), smoker, Hoehn and Yahr stage (off), preoperative use of amantadine, hypnotic, Hamilton anxiety scale and Hamilton depression scale scores, and postoperative limited noninfectious peri-electrode edema in deep white matter were suspected risk factors for postoperative hiccups (p < 0.1). In binary multivariate logistic regression analysis, male (compared to female, OR 14.00; 95% CI, 1.74−112.43), postoperative limited noninfectious peri-electrode edema in deep white matter (OR, 7.63; 95% CI, 1.37−42.37), preoperative use of amantadine (OR, 3.64; 95% CI, 1.08−12.28), and higher BMI (OR, 3.50; 95% CI, 1.46−8.36) were independent risk factors for postoperative hiccups. Conclusions: This study is the first report about the risk factors of hiccups after STN DBS under general anesthesia for PD patients. The study suggests that male, higher BMI, preoperative use of amantadine, and postoperative limited noninfectious peri-electrode edema in deep white matter are independent risk factors for postoperative hiccups of STN-DBS for PD patients. Most hiccups after STN-DBS for PD patients were transient and self-limiting.

Effectiveness and safety of metoclopramide in treatment of intractable hiccup: a protocol of systematic review and meta-analysis

INTRODUCTION

Hiccup is a common disease that not only occurred on adults but also on infants, which can severely do harm to patients' physical and psychological health. Metoclopramide has been reported to have effects on intractable hiccup. However, there is a limited evidence that describes the efficacy and safety of metoclopramide in the treatment of intractable hiccup. The aim of this article is to obtain evidence on the effectiveness and safety of metoclopramide in treating patients with intractable hiccup.

METHODS AND ANALYSIS

We will search the following databases, including PubMed, Cochrane Library, Embase, Web of Science, CBM, Wan-fang, VIP database, CNKI and MEDLINE from their inception to 11 November 2021. All the randomised controlled trials associated with metoclopramide in treating intractable hiccup will be included. Articles screened, selected and extracted will be performed by two researchers independently. The risk of bias will be assessed by using the Cochrane Collaboration. We will carry out the meta-analysis by using RevMan V.5.4 software.

PROSPERO REGISTRATION NUMBER

CRD42021293000.

Acute Hiccups Detected by Electromyographic Recordings During Resection of a Vestibular Schwannoma

BACKGROUND AND IMPORTANCE

Intraoperative neuromonitoring (IONM) is routinely used to monitor cranial nerve function during resection of vestibular schwannomas. Sudden movements in the surgical field can be a disturbing factor for the surgeon. IONM can help determine the cause of unexpected patient movements.

CLINICAL PRESENTATION

We report the case of a 54-year-old patient who underwent retromastoid craniotomy and resection of a vestibular schwannoma. Toward the end of dissection of the tumor from the lower cranial nerves and brainstem, the patient showed repetitive shoulder elevation. Electroencephalography showed burst suppression, confirming deep sedation and excluding voluntary movements. Free-running electromyography recorded spontaneous, simultaneous, bilateral vocal cord activity that was synchronous with upper body movement. There was simultaneous but smaller activity in the right genioglossus muscle and levator veli palatini, indicative for far-field activity. These IONM findings allowed us to classify the clinical observations as intraoperative hiccups.

CONCLUSION

Hiccups during general anesthesia are rare but should be considered as a differential diagnosis of sudden upper body movement. To the best of our knowledge, this is the first reported case of acute hiccups during resection of a vestibular schwannoma. IONM reliably distinguished it from an increase in intraoperative consciousness or accessory nerve activation resulting in shoulder movements.

Persistent hiccup as one of the initial symptoms of leucine-rich glioma-inactivated-1 encephalitis: a case report

Background

Anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis, an autoimmune disorder, is characterized by faciobrachial dystonic seizures, epilepsy, memory deficits and altered mental status while hiccup is not commonly found in patients.

Case presentation

A 62-year-old male was presented with slurred speech, abnormal gait, faciobrachial dystonic seizures and impaired cognition. Besides, the hiccup was one of the initial symptoms. His brain magnetic resonance images (MRI) revealed multiple lesions with left caudate nucleus, putamen, insula and left hippocampus involvement. Because a diagnosis of antibody-related limbic encephalitis was suspected, studies including an autoimmune profile were done by cell-based assays. After anti-LGI1 antibodies were detected in both cerebrospinal fluid and serology, pulse methylprednisolone and intravenous immunoglobulin were started and hence hiccups disappeared along with other symptoms.

Conclusions

Clinicians should be aware that persistent hiccups might be one of the initial manifestations of LGI1 subtype of voltage-gated potassium channel complex antibody associated autoimmune encephalitis.

Intractable Hiccups Caused by Diaphragmatic Eventration

Intractable hiccups are a rare yet debilitating pathology with a broad differential and often indicate a more serious underlying pathology, which can range from neoplasms to structural abnormalities. In this case report, we present a 64-year-old male with seven months of intractable hiccups determined to be caused by eventration of the right hemidiaphragm. The patient was treated with baclofen to treat the hiccups pharmacologically. He was also prescribed voice therapy to establish rescue breathing techniques and reduce laryngospasm. Finally, he was referred to thoracic surgery for further evaluation and potential surgical intervention should his diaphragmatic eventration worsen or cause hypoxemia. To our knowledge, this is the first reported case of an association between diaphragmatic eventration and intractable hiccups. It is important to highlight this addition to the broad differential of intractable hiccups and to emphasize an interdisciplinary approach to workup and treatment of intractable hiccups.

Midazolam-Induced Hiccups Reversed by Flumazenil: A Case Report

Hiccups are a common phenomenon experienced by many people and are usually short-lived with spontaneous resolution of symptoms. Certain anesthetic medications have been associated with the development of hiccups, though the underlying pathophysiology and reflex arcs remain poorly understood. We describe a patient who developed hiccups lasting 9 days following an orthopedic surgery and again developed hiccups during a subsequent surgery after only having received midazolam; flumazenil administration led to sustained cessation of his hiccup symptoms immediately.

Persistent hiccups after treatment of COVID-19 with dexamethasone: A case report

Hiccups are involuntary and spasmodic contractions of the diaphragm, and multiple etiological factors have been suggested to be involved. Medications, such as dexamethasone, as well as some diseases, such as pneumonia, can cause persistent (>48 h) hiccups. Here, we report a 58-years-old male who had a fever, myalgia, cough, and ground-glass view in the chest computed tomography, and his PCR test for Covid-19 was positive. During the treatment course, persistent hiccups were developed after taking dexamethasone and lasted for six days. All cardiac and neurologic examinations were performed, and all of them were normal. After evaluating all of the possible underlying causes, dexamethasone was replaced by prednisolone. Upon a change in his treatment regimen, hiccups began to stop, and his symptoms also disappeared. Hiccups may occur in patients who have pneumonia and other infectious diseases. Dexamethasone can also stimulate hiccups along with infections.

When hiccups mean something more than just a nuisance: A rare presentation of pyogenic liver abscess

Pyogenic liver abscess (PLA) is an uncommon yet potentially fatal disease. The disease most commonly arises from biliary infection but may also result from hematogenous seeding and portal spread secondary to bowel contamination, direct seeding, or penetrating trauma. The diagnosis is suspected when there is a hepatic lesion on imaging. Confirmation of diagnosis requires purulent aspirate or bacterial growth on Gram stain/culture of the abscess or blood. The mainstay of treatment is antimicrobials in conjunction with either percutaneous abscess drainage or aspiration. Surgical drainage is reserved for cases of ruptured abscess, peritonitis, or in the presence of an underlying surgical cause. PLA typically presents with fever and abdominal symptoms. We report a case of an unusual manifestation of PLA, presenting as hiccups, which led to a significant delay in the diagnosis and treatment.

Clinical characteristics of intractable or persistent hiccups and nausea associated with herpes zoster

AIM

Intractable or persistent hiccups and nausea (IHN) are rarely associated with herpes zoster (HZ-IHN). We aimed to identify the clinical characteristics of HZ-IHN by comparing them with those of neuromyelitis optica spectrum disorder associated with IHN (NMOSD-IHN).

METHODS

We collected 8 patients with HZ-IHN and 12 patients with NMOSD-IHN diagnosed between 2002 and 2020 from medical databases. Medical records including clinical information, laboratory data on serum anti-aquaporin 4 (AQP4) antibodies, serological or cerebrospinal fluid findings for the varicella zoster virus, medullary MRI findings, and efficacy of intravenous methylprednisolone pulse (IVMP) therapy were analyzed retrospectively.

RESULTS

The age of onset (69 ± 13 years versus 46 ± 17 years, P = 0.003), percentage of men [7/8 patients (88%) versus 3/12 patients (25%), P = 0.020], serum CRP levels (1.41 ± 1.17 mg/dL versus 0.14 ± 0.33 mg/dL, P = 0.018), and frequency of hemi-cranial nerve involvement [6/8 patients (75%) versus 1/12 patients (8%), P = 0.004] were significantly higher in patients with HZ-IHN than in those with NMOSD-IHN. The hypoglossal and vagus nerves were involved in 5/8 patients (63%) with HZ-IHN. Other clinical parameters, excluding anti-AQP4 antibodies, were similar to those of NMOSD-IHN. MRI revealed ipsilateral hemi-dorsal medullar hyper-intense lesions in 5/8 patients (63%) with HZ-IHN. Acyclovir with IVMP therapy was effective for HZ-IHN.

CONCLUSION

Clinicians should include HZ-IHN in the differential diagnosis for IHN, and promptly administer acyclovir and IVMP therapy. HZ-IHN is frequently accompanied by lower hemi-cranial nerve palsies and ipsilateral hemi-dorsal medullary hyper-intensity on MRI.

DATA AVAILABLE STATEMENT

The authors confirm that the data supporting the findings of this study are available within the article (Tables 1 and 2), or its supplementary materials (Table S1).

Efficacy of acupuncture for persistent and intractable hiccups: A protocol for systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Persistent and intractable hiccups are a common clinical symptom that cause considerable physical pain to patients and severely damage their quality of lives. An increasing number of studies have demonstrated that acupuncture applied at acupoints dominated by Cuanzhu (BL2) can be used as one of the nonpharmacological therapies for controlling intractable hiccups. However, there is insufficient evidence evaluating the safety and effectiveness of those interventions. Therefore, this study is intended to conduct a systematic review and meta-analysis to provide evidence for a further study investigating alternative treatment options for persistent and intractable hiccups.

METHODS AND ANALYSIS

Randomized controlled trials (RCTs) of adult patients aged >18 years who meet the criteria for intractable hiccup diagnosis will be included, regardless of gender, nationality, and education level. Eight electronic databases will be searched, including 4 Chinese databases (CNKI, SinoMed, Wanfang Database, and Chinese Scientific Journal Database), 4 English databases (Web of Science, Medline, Embase, and Cochrane Library), from their date of establishment to September 2020. Two independent reviewers will evaluate the title summary for each RCT. Disagreements will be discussed with a third commentator. Data integration, heterogeneity analysis, subgroup analysis, and sensitivity analysis, will be performed using R-3.3.2 software. The RevMan 5.3 software will be used for the meta-analysis, and the "risk of bias" assessment will be conducted based on the methodological quality of the included trials recommended by the Cochrane Handbook 5.1. The quality evaluation of this study will be completed by the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).

RESULTS

This study will summarize all the selected trials aimed at estimating the effectiveness, as well as safety, of applying acupuncture at acupoints dominated by Cuanzhu (BL2) to persistent and intractable hiccups.

CONCLUSIONS

This systematic review will provide evidence to assess the validity and safety of applying acupuncture at acupoints dominated by Cuanzhu (BL2) for persistent and intractable hiccups, which may provide clinicians with more choices in the treatment of this disease.

PROSPERO REGISTRATION NUMBER

CRD42020114900.

Neurological complications of COVID-19 in hospitalized patients: The registry of a neurology department in the first wave of the pandemic

OBJECTIVE

To describe the spectrum of neurological complications observed in a hospital-based cohort of COVID-19 patients who required a neurological assessment.

METHODS

We conducted an observational, monocentric, prospective study of patients with a COVID-19 diagnosis hospitalized during the 3-month period of the first wave of the COVID-19 pandemic in a tertiary hospital in Madrid (Spain). We describe the neurological diagnoses that arose after the onset of COVID-19 symptoms. These diagnoses could be divided into different groups.

RESULTS

Only 71 (2.6%) of 2750 hospitalized patients suffered at least one neurological complication (77 different neurological diagnoses in total) during the timeframe of the study. The most common diagnoses were neuromuscular disorders (33.7%), cerebrovascular diseases (CVDs) (27.3%), acute encephalopathy (19.4%), seizures (7.8%), and miscellanea (11.6%) comprising hiccups, myoclonic tremor, Horner syndrome and transverse myelitis. CVDs and encephalopathy were common in the early phase of the COVID-19 pandemic compared to neuromuscular disorders, which usually appeared later on (p = 0.005). Cerebrospinal fluid severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction was negative in 15/15 samples. The mortality was higher in the CVD group (38.1% vs. 8.9%; p = 0.05).

CONCLUSIONS

The prevalence of neurological complications is low in patients hospitalized for COVID-19. Different mechanisms appear to be involved in these complications, and there was no evidence of direct invasion of the nervous system in our cohort. Some of the neurological complications can be classified into early and late neurological complications of COVID-19, as they occurred at different times following the onset of COVID-19 symptoms.

Preliminary experimental outcomes of induced hypercapnia in treatment of obstinate singultus

Background

Our team found that abolishing the venous-arterial CO₂ gradient can cease singultus (hiccups), in which the CO₂ pressure in blood reaches no less than 50 mmHg. In order to precisely investigate the target level as a preliminary study, we made a combination gas consisting of 10% CO₂ and 90% O₂ to generate the conditions instantly and safely.

Methods

Thirty-five cases consisting of 26 patients with long-term chronic singultus were treated using the gas. The group consisted of 21 males and 5 females with mean singultus duration of 8.0±13.1 years. A standard oxygen mask was used for delivery of the gas to the patients, and patients breathed in the gas until they felt relief. The duration of the procedure was measured from the beginning to the point at which singultus ceased. A blood test was performed to measure the partial pressure of CO₂ in venous blood at the point at which singultus ceased.

Results

Singultus ceased in all patients in a mean time of 5.3±1.5 minutes, with complete recurrence observed in two cases. The mean partial pressure of CO₂ in the venous blood at the point the singultus stopped was 60.8±6.8 mmHg. No life-threatening complications were found in any patient.

Conclusions

One of the definitive conditions for ceasing singultus is acute CO₂ retention in the body, the target of which is around 60 mmHg of CO₂ in venous blood. We believe that targeting acute hypercapnia can always stop singultus, although further neuroscientific investigation is necessary to reveal the physiological mechanism.

Chronic Hiccups

PURPOSE OF REVIEW

Nearly 4000 patients will be admitted to hospital in the US this year for hiccups. Hiccups are controlled by a complex reflex arc between peripheral receptors and the brainstem. Any disruption along this pathway may produce hiccups. Typically, hiccups resolve spontaneously but in certain pathologies symptoms may persist. Persistent hiccups may be considered a sign of underlying pathology. The most common cause involves GERD.

RECENT FINDINGS

Based on etiologies, studies have shown that first-line therapy should use a proton pump inhibitor (PPI) and involve appropriate gastrointestinal consultation. If symptoms persist, other etiologies such as central causes need to be explored.

SUMMARY

We review the pathophysiology of hiccups including multiple causes and the appropriate work up for each. We review several studies examining new treatments, both pharmacological and interventional, that may help patients. Initial therapy should still involve a PPI but several new therapies may be beneficial.