The aim of this prospective, observational study is to determine the incidence of post-operative residual neuromuscular blockade (PRNB) in patients undergoing intra-abdominal procedures compared to patients undergoing other noncardiac/non intra-thoracic procedures that also require non-depolarizing neuromuscular blocking agents (NMBA) administration. As intra-abdominal surgeries are independently associated with post-operative pulmonary complications (PPCs), it is important to highlight other factors, such as PRNB, that could contribute to these complications.Although it has been shown that the risk of adverse respiratory events can be reduced by intra-operative quantitative neuromuscular monitoring, such monitoring is not in widespread use.This study will incorporate quantitative monitoring in the post-anesthesia care unit (PACU) setting by using the Stimpod NMS450® in an effort to show a disparity in the incidence of residual paralysis between these two patient populations and to emphasize the need to implement more accurate neuromuscular monitoring, especially for those that are already at increased risk for respiratory complications.

Residual paralysis from non-depolarizing neuromuscular blocking agents (NMBAs) is a common problem that contributes to adverse outcomes in the post-anesthesia care unit (PACU).Unidentified residual neuromuscular blockade (defined as a train-of-four (TOF) ratio <0.9) has been reported in up to 30-42% of patients in the recovery room.Though current literature supports the use of quantitative monitoring of neuromuscular blockade, conventional qualitative TOF count monitoring and clinical signs (head lift, grip strength) continue to be used.There is strong evidence that shows reduction of clinically significant post-operative residual neuromuscular blockade (PRNB) after implementation of quantitative monitoring. Post-operative pulmonary complications (PPCs) are notable adverse outcomes of residual neuromuscular blockade. The implementation of quantitative monitoring may be particularly beneficial to patients who are already predisposed to PPCs secondary to the site of surgery.

The purpose of this study is to evaluate the incidence of PRNB with use of quantitative neuromuscular monitoring in patients undergoing intra-abdominal procedures compared to patients undergoing other surgical procedures that also require NMBA administration.

Inclusion Criteria:

• English speaking

• ASA physical status classification I-IV

• Procedures requiring intubation and nondepolarizing NMBA administration

  • Laparoscopic surgery
  • Intra-abdominal surgery
  • Procedures using the Da Vinci surgical system
  • Tonsillectomy
  • Septoplasty
  • Shoulder surgery
  • Total hip arthroplasty
  • Carotid endarterectomy
  • Cervical spine surgery
  • Parotidectomy
  • Thyroidectomy
  • Aorto-bifemoral bypass
  • Micro laryngoscopy
  • Nasal or sinus surgery
  • Dental extraction

Exclusion Criteria:

• Non-English speaking population
• ASA V and VI
• Unable to give informed consent
• Cardiac or intra-thoracic procedures performed
• Severe renal insufficiency (Serum Creatinine >2.0 mg/dL)
• Severe hepatic dysfunction
• Underlying neuromuscular disease
• Currently enrolled in another therapeutic study
• Pregnant patients at any stage of pregnancy

The study population will include all patients age 18 or older with American Society of Anesthesiologists (ASA) physical status I-IV presenting for elective or non-elective surgery requiring general anesthesia with neuromuscular blockade.While previous studies have found that up to 30-42% of patients experience PRNB in the PACU, no previous studies have estimated the incidence of PRNB by surgical procedure (i.e., intra-abdominal versus other surgical procedures).Therefore, this study will be more descriptive in nature.A difference of at least 10% in the incidence of PRNB between the two groups will be considered clinically significant.A maximum number of 120 (approximately 60 patients who undergo intra-abdominal surgery and 60 patients who undergo non intra-abdominal surgical procedures) will be enrolled during the course of the study.