Treatment of persistent hiccups after arthroplasty: effects of acupuncture at PC-6, CV-12 and ST-36

This observational study investigated the effects of acupuncture in the treatment of persistent hiccups after arthroplasty, a postoperative complication that can cause significant discomfort and interfere with patient recovery. Persistent hiccups are defined as those lasting more than 48 hours and can cause insomnia, exhaustion, surgical wound dehiscence, dehydration, and weight loss. Although several pharmacological treatment options exist, none has demonstrated clear superiority and many carry adverse effects, generating interest in non-pharmacological approaches such as acupuncture. The study was conducted between April 2010 and December 2015 at the Changzhou Hospital of Traditional Chinese Medicine.

Fifteen patients aged 62-75 years who developed persistent hiccups after primary unilateral hip or knee arthroplasty were included. The patients had hiccups for an average of 84.3 hours before treatment, with initial scores on the HAI (Hiccups Assessment Instrument) scale of 7.6±2.2, indicating a significant impact on quality of life. The acupuncture protocol was standardized, using three specific points: PC-6 (Neiguan), CV-12 (Zhongwan), and ST-36 (Zusanli). These points were selected based on Traditional Chinese Medicine theory and their historical use for gastrointestinal and respiratory disorders.

An experienced acupuncturist performed all sessions, which lasted 30 minutes each. Needles were manipulated manually to elicit "de qi," characterized by sensations of pressure, soreness, distension, and numbness. The total number of sessions was determined by the persistence of symptoms, with a maximum of three treatments in one week. The results were notably positive.

All 15 patients achieved complete hiccup resolution (HAI score = 0) within fewer than three sessions. Ten patients (66.7%) required only one session, three patients needed two sessions, and only two patients required all three sessions. The HAI score improved significantly after each round of treatment (P<0.05), demonstrating progressive efficacy. Accompanying symptoms such as pain in the diaphragmatic area, mild dyspnea, dysphagia, and nausea/vomiting also disappeared completely with the resolution of hiccups.

No adverse effects related to acupuncture treatment were observed during the entire study period. The researchers proposed several possible mechanisms to explain the efficacy of acupuncture. The hiccup reflex involves afferent pathways (vagal, phrenic, and sympathetic), efferent pathways (the phrenic nerve and nerves innervating the glottis), and a central connection in the cervical spinal cord. Acupuncture could modulate any part of this reflex arc through increased perfusion, alteration of axonal excitability, or neuromodulation of the autonomic nervous system.

The selected points have neuroanatomic relationships with the upper gastrointestinal tract and may improve abnormal gastroesophageal function through somato-visceral pathways. The study used the HAI scale as an assessment tool, allowing objective quantification of symptom improvement. This was the first time a continuous variable was used to assess the impact of an intervention on persistent hiccups, representing an important methodological advance. The clinical implications are significant, as acupuncture appears to be a safe and potentially effective alternative to conventional pharmacological treatments.

The technique is minimally invasive, presented no adverse effects in this study, and demonstrated a high success rate. However, the study has important limitations that should be considered when interpreting the results.