Methods

All elective new permanent pacemaker implants have been performed as same day cases since 1998 at the University Hospital of North Staffordshire (Stoke on Trent, United Kingdom). Patients admitted to hospital with symptoms and pacemaker indications (i.e., nonelective cases) did not undergo implantation as a same day procedure. Data regarding the pacemaker implants have been entered into our pacing database since April 2001. We performed a retrospective analysis of all patients implanted with a pacemaker intended as a same day procedure from April 2001 to December 2006. The information collected included the baseline patient characteristics, indications for pacing (according to the European Pacemaker Patient Identification Card), device and lead details, lead implant data, route of vascular access, use of antiplatelet/anticoagulant medication, and peri- and postimplant complications. We also recorded the details of all hospital admissions after elective pacemaker implantation, with the reasons for admission. All patients were routinely reviewed in the pacemaker clinic 6 weeks after implantation. The details of the complications developing immediately after implantation (defined as <24 hours) and early after implantation (>24 hours to 6 weeks) were recorded into the database. The implanting physicians included consultant cardiologists, senior cardiology fellows, and junior cardiology fellows supervised by a consultant or senior fellow. Patients taking antiplatelet therapy (e.g., aspirin or clopidogrel) were allowed to continue them. Those taking warfarin were requested to stop warfarin 3 days before implantation, if possible. Those unable to do so (e.g., patients with prosthetic metallic valves) were formally admitted and switched to heparin and did not undergo a same day procedure. All patients undergoing elective same day implantation had device checks 2 hours after implantation, and all underwent departmental chest radiography after the procedure. Patients were observed for ≥4 hours after implantation. If all checks were satisfactory, the patients were discharged home. All patients were then followed up in the pacemaker clinic at 6 weeks.

Mortality data were collected for the entire cohort to identify how many patients died during follow-up and whether any deaths were related to pacemaker implantation. The details regarding the costs of an overnight hospital stay were obtained from our Finance Department, and an assessment of the potential cost savings performed for November 2005 to November 2006.

All data were analyzed using Statistical Package for Social Sciences, version 15.0 (SPSS, Chicago, Illinois). Tests of normality were done using Minitab Ltd, version 13.0 (Coventry, United Kingdom). Continuous variables assuming a normal distribution are expressed as the mean ± SEM, and nominal data are presented as numbers and percentages. Comparisons between the normally distributed unmatched data were done using the unpaired t test. Comparisons between nonparametric unmatched data were made using the Mann-Whitney U test (continuous data) and the chi square test (nominal data).

Results

A total of 780 patients underwent elective pacemaker implantation from April 2001 to December 2006, with all intended to be a same day procedure. The mean age of the cohort was 73.8 ± 0.4 years (464 men [59%] and 316 women [41%]). All patients received antibiotics before or during implantation. Preoperative intravenous antibiotics were administered to 219 patients (28%); these patients received intravenous flucloxacillin 1 g before implantation, unless they were allergic to penicillin, in which case they received one dose of intravenous vancomycin before implantation (500 mg to 1 g). Perioperative antibiotics were given to 561 patients in the form of gentamycin into the pacemaker pocket. All received postoperative oral penicillin derivatives for 5 days; those with a penicillin allergy received an alternative antibiotic (eg, a macrolide).

The details of the pacing indications are listed in Table 1 . Because these patients were elective cases, none were pacemaker dependant. During implantation, the minimum P and R waves accepted were 2 and 5 mV, respectively. All patients had an injury current checked and tests of stability (deep inspiration and coughing) performed before accepting the final lead position. A maximum 10 V output test was also done to ensure no phrenic nerve stimulation. Venous access was the subclavian vein in 431 patients (55%) and the cephalic vein in 349 (45%). Unipolar atrial leads were implanted in 57% and passive atrial leads in 84%. The mean data for the atrial lead were as follows: P wave 2.6 ± 0.08 mV, lead impedance 577.2 ± 6.4 Ω, and pacing threshold 0.7 ± 0.02 V at 0.5 ms. Unipolar ventricular leads were implanted in 40% and passive ventricular leads in 80%. The mean data for the ventricular lead were as follows: R wave 9.9 ± 0.2 mV, lead impedance 766.5 ± 6.6 Ω, and pacing threshold 0.5 ± 0.01 V at 0.5 ms. The manufacturer of the implanted atrial leads was St. Jude Medical Inc. (St. Paul, Minnesota) (83.3%), Medtronic Inc. (Minneapolis, Minnesota) (11.6%), Guidant (Boston Scientific, Boston, Massachusetts, 4.7%), and Oscor Inc. (Palm Harbor, Florida) (0.4%). The manufacturer of the implanted ventricular leads included St. Jude Medical (76%), Medtronic (8%), Biotronik SE & Co. KG (Berlin, Germany) (12%), and Guidant (4%).

Of the 780 patients, 41 (5.3%) required an inpatient stay after implantation. The reasons for admission included hematoma formation in 12, pneumothorax in 3, observation at the physician’s request without an immediate complication for 13, social reasons (eg, living alone, no transport, or living a long distance from the hospital) for 7, the development of angina during or immediately after implantation with perforation excluded in 3, induction of fast atrial fibrillation in 1, and warfarin therapy with an elevated international normalized ratio (>2.0) in 2 patients. All these patients were discharged 1 to 3 days later with no long-term adverse consequences. A comparison of those requiring an overnight stay and those discharged the same day revealed no differences in age (75.1 ± 1.8 vs 73.7 ± 0.4 years, p = 0.6), use of antiplatelet therapy (93% vs 87%, p = 0.6), subclavian vein access (63% vs 55%, p = 0.4), or any of the pacing parameters at implantation.

Immediate complications were noted in 6 patients after implantation. Of these 6 patients, 2 were admitted with displaced atrial leads and presented with dizziness and palpitation, 1 presented with an elevated ventricular threshold without displacement (confirmed by chest radiography), 2 had sensing problems on the atrial lead, and 1 developed a hematoma requiring evacuation. Early complications occurred in 17 patients. Of these 17 patients, 5 had lead displacements (3 atrial and 2 ventricular), 6 had high pacing thresholds (4 atrial and 2 ventricular), 3 developed a wound infection (2 superficial that resolved with antibiotic therapy with no bloodstream infection and 1 who required system explant and did have a bloodstream infection with Staphylococcus aureus ), 2 had sensing problems, and 1 patient developed subclavian vein thrombosis. Of the 780 patients, 94 died during a mean follow-up of 4.6 ± 0.06 years. The mean age of those who died was 78.4 ± 0.8 years. The mean interval from pacemaker implantation to death was 2.4 ± 0.1 years. None of the deaths were related to pacemaker implantation.

A total of 109 patients underwent implantation with a pacemaker from November 2005 to November 2006. None required an overnight stay during this period. However, 2 patients developed lead displacements requiring readmission for lead repositioning at the cost of an extra 2 days in the hospital. The cost of an overnight hospital stay during this period was £203.60 (∼US$305). The cost savings to our unit from adopting a same day policy during this period was calculated at £21,785 (∼US$34,500). Extending this for a period of several years represented a significant cost savings for our hospital.

A total of 539 patients underwent nonelective pacemaker implantation during the study period (April 2001 to December 2006). These patients did not undergo same day pacing. The immediate and early complication rates were not different between this cohort and those who had undergone same day pacing.